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Safety and clinical use of exercise testing one to three days after percutaneous transluminal coronary angioplasty
Safety and Clinical Use of Exercise Testing One to Three Days After Percutaneous Transluminal Coronary Angioplasty Gary J. Balady, MD, Mark L. Leitschuh, MD, Alice K. Jacobs, MD, Denise Merrell, BS, Donald A. Weiner, MD, and Thomas J. Ryan, MD
To evaluate both the safety and clinical use of predischarge symptom-limited exercise testing after successful uncomplicated percutaneous tranduminal coronary angtoplasty (PTCA), 199 patients were randomized to undergo exercise testing (n = 50) or no exercise testing (n = 90). There were no differences in clinical or angiographic characteristics between the groups. Exercise testing was performed 39 f 14 hours after PTCA. Patients who exercised achieved 71 f 12% of predicted maximal heart rate, wtth 38% reaching I stage III of the Bruce protocol. No patient in either group developed cardiac complications during 49 hour follow-up. Of the 11 patients with a positive test result, 92% had angiographically incomplete revascutartxatton. Attending physicians (n = 16) were questfoned both before and after exercise testing about when, after discharge, they would allow their pattent to perform each of 11 specific activtttes of daily living. Questttnnaires were administered to physfcians at stmilar time frames for patients in the no-exercise group. Comparfson of the responses between inttial and repeat questionnaires showed that patients in the exercise group (with a test result negative for ischemia) were allowed to perform 7 of 11 acttvtties, includtng return to work, earlier (p <0.09) than the no-exercise patients. These data indicate that in this welidefined group of patients, symptom-iimtted exercise testing early after PTCA appears to bs safe, and alters phystcian management in allowing patients with a negative test resutt to return to various activtttes at an earlier date. Such testing may be useful in counseting patients after PTCA. (AmJCardid 1992;69:1259-1264)
From the Department of Medicine and the Evans Memorial Department of Clinical Research, The University Hospital/Boston University Medical Center, Boston, Massachusetts. Manuscript received November 6,1991; revised manuscript received January 10,1992, and accepted January 11. Address for reprints: Gary J. Balady, MD, Section of Cardiology, The University Hospital, 88 East Newton Street, Boston, Massachusettso2118.
xercise testing is a widely used method employed in the managementof patientswith coronary artery diseaseand is particularly valuable in assessing cardiovascular status after the occurrence of a cardiac event or therapeutic intervention. Percutaneoustransluminal coronary angioplasty (PTCA) is a major modality of coronary revascularization with well over 200,000 procedures performed annually in the United States alone.’ Therefore, the issue of patient evaluation after successful PTCA is of growing importance. Exercise testing after PTCA has potential to yield useful information, such as the (1) assessmentof a patient’s functional ability for use in activity prescription; (2) establishment of the adequacy of revascularization, particularly in a patient in whom PTCA has beenperformed as an incomplete revascularization strategy; (3) assessment of symptoms such as chest pain or dyspnea after the procedure; and (4) prediction of future cardiac events, including restenosis. Previous studies regarding such testing have focused primarily on its value in assessing prognosis.*-l3 However, there is little information regarding the role of the exercisetest in patient management after angioplasty. Although exercise testing 17 days after PTCA has generally been consideredsafe,14 there are severalcasereports15-17 that document the occurrence of serious complications within minutes after exercisetesting has been performed early after PTCA. Therefore, the purpose of this study was to evaluate symptom-limited exercise testing before hospital discharge, as early as possibleafter successfulPTCA, in a well-defined population with regard to the safety of the procedure and its clinical utility.
E
METHOD8 An overview of the study methodsis outlined in Figure 1. A total of 160 consecutiveeligible patients were approached for enrollment into the study after undergoing successfulPTCA. Of these, 100 patients agreed to participate. Patients were deemedineligible from the study for any of the following reasons:(1) myocardial infarction within 3 weeks; (2) inability to exercise because of hemodynamic instability, neurologic or ortho pedic impairment; (3) unsuccessful coronary angioplasty or large intimal dissection,or both, after the procedure; (4) definite signs or symptomsof ischemia after PTCA (these patients were excluded from randomization becausethe developmentof ischemia after exercise testing was considereda study end point); and (5) femoral site vascular complication after PTCA including painful area, hematoma >3 mm, or pseudoaneurysm. EXERCISE TESTING AFTER CORONARY ANGIOPIASTY
1259
The 100 study patients were randomized into 2 (1) exercise group - consisting of 50 patients who performed symptom-limited exercise testing after PTCA before hospital discharge; and (2) no-exercise (control group) - 50 patients who did not perform the predischargeexercisetest after PTCA. Information was obtained regarding the patient’s age, sex, employment status, medications, angina1class, and history of previous myocardial infarction. Informed consent was obtained in accordance with the Institutional Review Board for Human Researchat the University Hospital/ Boston University Medical Center. and angiographii analysis: cor0MlywcW-Q All randomized patients underwent successfulPTCA in the cardiac catheterization laboratory at the University Hospital. This was defined as a change in lumen diameter of 220% and a residual stenosisof 150% in all attempted lesions without associated in-hospital death, myocardial infarction or emergency coronary bypass surgery. The narrowings were measuredby calipers in 2 orthogonal views. Before PTCA, all lesions were characterized into types A, B or C based on previously established criteria? type A lesionswere deemedto have the highest success/lowestrisk; type B were considered intermediate, and type C, the lowest success/highest risk. Intimal dissection after PTCA was defined as intima1 damage producing an intraluminal filling defect (tear), extravasation of contrast material or linear luminal density staining, and was graded from mild to severe according to previously described detinitions.i9 Revascularization after PTCA was “complete” if there was no remaining stenosisof 170% in a major coronary artery or branch (11.5 mm in diameter) and “incomplete” if there was such a residual stenosis.Revascularization was judged “adequate” if there was no remaining lesion of 170% in a vessel 11.5 mm in diameter that servedviable myocardium (indicated by the preservation of regional wall motion distal to a stenosison left ventriculography). Restenosiswas defined angiographitally by the presenceof 150% stenosisat the site of the previous PTCA. Exercise tosting: All 50 patients in the exercise group underwent symptom-limited exercise testing in groups:
METHODS PATIENTS
ELIGIBLE POST-PTCA
RANDOMIZEGOJb EXERCISE
(160)
REFUSED (60)
GROUPH (50) >EXERCISE GROUP’ (50) 1 1 l Clinical and angiographic data l Initial physician questionnaire
1 Symptom limited exercise test (BRUCE PROTOCOL) 1 l l l
1 No exercise 1
test
Repeat physician questionnaire 48 hour post-PTCA clinical follow-up 18 month clinical followup
FlGUREl.AlglIdh~theStUdyprOtOCd.Nunbershp8fmfhe8esrefartolhemmnberofpathtsin~
cabgoryasdetdlsdhthetext.PlCA=perahmwtransh---.
1260
THE AMERICAN JOURNAL OF CARDIOLOGY VOLUME 69
the exerciselaboratory at the University Hospital 1 to 3 days after PTCA before hospital discharge.Patients exercised while taking their usual medications, using either the standard Bruce (45 subjects)or modified Bruce protocol (5 subjects).2oThe protocol was selectedbased on the investigators’ (GJB or MLL) perception regarding the patient’s ability to ambulate. Exercise was terminated for any of the following reasons:moderate angina, definite ischemic ST-segmentdepression13 mm, significant fatigue, and complex ventricular ectopy or exertional hypotension. Heart rate, blood pressure and 1Zlead electrocardiogramswere obtained at rest, during each minute of exercise,at peak exerciseand during recovery. A positive responsewas defined as having either definite angina during testing or 11 mm of horizontal or downsloping ST-segmentdepression,or Il.5 mm of upsloping ST depressionat 0.08 secondafter the J point in 3 consecutivebeats of the samelead. Patients were observedin the hospital for a minimum of 2 hours after the test. Clinical follow up: All patients in both groups were contacted by telephone approximately 48 hours after hospital discharge to evaluate the occurrence of any clinical events including: angina, repeat hospitalization, myocardial infarction, vascular complication or death. Patients who exercisedwere contacted by telephone at 18 f 4 months after the exercise test to evaluate the occurrence of clinical events including angina, myocardial infarction, repeat coronary angiography or death. These data were supplemented with information obtained from chart review. Physician management assessment: The evaluation of patient managementafter PTCA in the exerciseand no-exercisegroups was conducted by use of a questionnaire (Appendix I) that was administered to the attending physician of each individual study patient. This questionnaire requestedinformation regarding the timing of patient discharge and the allowanceof 11 specific household or leisure activities. Inquiries regarding return to work were limited to those who were employed before PTCA. Physicians were asked to define the timing of their allowance of each activity in terms of days after hospital discharge according to the following choices: 1 to 7 days (score = l), 8 to 14 days (score = 2), 15 to 21 days (score = 3) after 21 days (score = 4) or “never” (score = 5). Identical questionnaires were verbally administered by the sameinvestigator (GJB or MLL) to each physician initially after the PTCA before the exercisetest results were disclosed,and again after the exercise test results were revealed. Questionnaires regarding patients in the no-exercise group were also administered twice at a similar time frame as for those in the exercise group. Repeat questionnaires were administered at a separate time period from the initial one without disclosure or reference to the previous responses.Comparisons between the initial and repeat responseswere used to determine the impact of the exercise test on management strategy using the “beforeafter” analysis method.21For easeof statistical comparison, differences between initial and repeat responses were reported as a time shift index. This was calculated by taking the difference in the mean time scores for MAY 15, 1992
APPENDtX I -
Physician Management Questionnaire
1) When do you plan to discharge the patient -days
from PTCA?
2) Do you plan any change of medications at this time? -(l) add _ (2) decrease _ (3) no change 3) When _ _ _ _ _
will you allow your patient to return to work? (1) l-7 days after discharge (2) 8-14 days after discharge (3) 15-21 days after discharge (4) After 21 days (5) Never
4) When _ _ _ _ _
will (1) (2) (3) (4) (5)
you allow your patient to drive? l-7 days after discharge 8-14 days after discharge 15-21 days after discharge After 21 days Never
6) When _ _ _ _ _
will (1) (2) (3) (4) (5)
you allow your patient to engage in sexual activity? l-7 days after discharge 8-14 days after discharge 15-21 days after discharge After 21 days Never
7) When will you allow your patient to perform household activities such as vacuuming or mowing the lawn? _ (1) l-7 days after discharge _ (2) 8-14 days after discharge _ (3) 15-21 days after discharge _ (4) After 21 days -(5) Never 8) If it were winter when would you allow the patient to shovel snow? _ (1) l-7 days after discharge _ (2) 8-14 days after discharge _ (3) 15-21 days after discharge _ (4) After 21 days _ (5) Never 9) When would you leisure activity? golf: -cl) _ _ _ -(5) bowling: _ _ _ _ _ walking: _ _ _ _ _ jogging: _ _ _ _ -(5) skiing: _ _ _ _ -(5) tennis: _ _ _ _ -(5)
allow your patient to participate in the following l-7days (2) 8-14 days (3) 15-2 1 days (4) After 21 days Never (1) l-7 days (2) 8-14 days (3) 15-2 1 days (4) After 2 1 days (5) Never (1) l-7 days (2) 8-14 days (3) 15-2 1 days (4) After 2 1 days (5) Never (1) l-7 days (2) 8-14 days (3) 15-21 days (4) After 21 days Never (1) l-7 days (2) 8-14 days (3) 15-21 days (4) After 2 1 days Never (1) l-7 days (2) 8-14 days (3) 15-21 days (4) After 21 days Never
1 TABLE I Exercise Test Responses
(n = 50)
Heart rate peak (beats/mm) % predicted maximal heart rate Rate-pressure product peak fbeats/min x mm Hg) Final exercise stage 5 Bruce stage I Bruce stage II Bruce stage Ill t Bruce stage IV No. of positive tests for angina or ischemic ST changes
I 120 k 21 71 k 12% 18.2 + 5.8 x lo3 13 18 13 6 11
(26%) (36%) (26%) (12%) (22%)
each activity between the initial and the repeat questionnaires. A “negative” time shift reflected the allowance of the activity at an earlier time frame from the initial response,while a “positive” time shift indicated the allowance of an activity at a later time frame. The time shifts were comparedbetweenthe exerciseand noexercisegroups using the non paired t test. StatistIcal analysis: Mean and standard deviations were calculated for all clinical and exercise test variables. Comparisons between groups were made using the non paired t test or chi-square evaluation. A probability level <0.05 was used to define statistical signilicance. RESULTS Patknl popubtion: Mean age of the 100 patients was 57 f 11 years, with 83% being men. All were taking medications at the time of FTCA including aspirin (lOO%), calcium channel antagonists (98%), /3 adrenergic-blocking agents (43%) and digoxin (8%). New York Heart Association class III or IV angina was reported in 48%, whereasunstable angina before PTCA was seen in 21%. Over one third of the patients had multivessel coronary artery disease and underwent multivessel FICA. Lesions were located with near equal distribution in the left anterior descending(38%), left circumflex (24%) and right coronary arteries (38%). The majority of lesions (61%) were classified as type A, whereas 33%were type B and 6% type C. Mean percentageof lumen diameter stenosisafter FTCA was 22 f 3%. Revascularization was deemed adequate in all patients, with most (70%) classified as “complete-adequate” and 30% as “incomplete-adequate.” When each of these characteristics were analyzed separately for the exercise group versusthe no-exercisegroup, there were no significant differences. However, more of the no-exercise group were employed (78%) comparedwith the exercise group (58%) (p <0.05). Small to moderate dissections were noted after PTCA in 5 patients (10%) in the exercise group compared to 6 (11%) in the noexercise group. Exercise te&Ingr The 50 patients in the exercise group underwent exercise testing approximately 38 f 14 hours (range 21 to 72 hours) after F’TCA. The results are listed in Table I. No patient was limited by leg pain at the catheter insertion site. There were 11 (22%) positive test results, with 7 demonstrating ischemic ST depressionwithout angina, 2 with ischemic ST depression and typical angina, and 2 with typical angina and no ischemic ST depression.Ten of 11 patients (92%) EXERCISE TESTING AFTER CORONARY ANGIOPIASN
1261
with a positive test responsehad incomplete-adequate revascularization. Conversely, of the 19 patients in the exercise group who had incomplete-adequaterevascularization, 10 (53%) had a positive exercise test response.However, there were no differencesin the extent of residual coronary artery diseaseor in the peak exercise variables achieved between those with a positive or a negative test result. Only 1 of 31 patients (3%) with completeadequate revascularization had a positive test. At a mean follow-up time of 51 f 25 hours after exercise testing, no patient in the exercise group demonstrated any complications, including the developmentor worsening of femoral area hematomas. However, at a similar follow-up time frame, 1 patient in the no-exercise group developeda femoral artery pseudoaneurysm at the catheterization site. Another 9 patients, who were originally excluded from randomization becauseof ischemic signs or symp toms after PTCA, underwent symptom-limited exercise testing at the request of their attending physician. Before exercise, 1 of these patients had a large dissection at the angioplasty site. Only 1 developed exercise-induced ischemic ST depression with angina while the other 8 test results were negative. None of these 9 patients developed any further angina or complications within 1 month after PTCA. Physkhmmagemdaftorpercutanaourtranslumind eoronuy B Initial and repeat manage-
ment questionnaireswere administered to 16 individual physicians regarding their respectivepatients enrolled in the study. Each managed an average of 6 (range 1 to 18) study patients. Discharge from the hospital was allowed within 2 days of PTCA in 90% of all patients and did not differ between groups. Comparison of the initial and repeat management responsesdemonstrated the time shift for allowance of 11 specific activities to be significantly “earlier” (p <0.05) in only 3 categories (return to work, snow-shoveling and skiing) in the exercise group versus the noexercisegroup. When the time shift indexes for patients
sr
1.
.
Walking
Exercise
Bowling 1.
Shoveling .
House
Snow Chores
Work
I
b -0.4
-0.3
-0.2
Earlier
-0.1
0
0.1
0.2
I 0.3
Later TIME SHIFT INDEX
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THE AMERICAN JOURNAL OF CARDIOLOGY VOLUME 69
in the exercisegroup with a positive ischemic response (n = 11) were compared with those having a negative response(n = 39) there was a trend toward the allowance of each activity to be performed earlier in those without ischemia, although this difference in time shift between groups did not reach statistical significance. Accordingly, the time shift indexes for exercise group patients without an ischemic test response (n = 39) were compared to those of the no-excercisegroup. Figure 2 shows the shift in time frame responseto be significantly earlier in 7 of 11 activities for patients with a negative exercisetest. Theseactivities included return to work, household chores (including lawn mowing and vacuuming), snow shoveling, walking for exercise,tennis, skiing and bowling. However, the time shift was not different between groups in 4 activities includiig driving, sexual activity, golf, and jogging. Table II outlines these responsesand showsthat the time frame shift for the allowance of any particular activity could occur at any 1 of the 5 time frame choices for each activity in each patient. Long-term follow-up: Long-term follow-up data were pursued for exercisegroup patients to determine if the exercisetest data were predictive of future cardiac events after hospital discharge. Successful follow-up was obtained in 46 patients (92%) at 18 f 4 months after PTCA, and the results are outlined in Table III. All 4 patients who were lost to follow-up had negative results on predischargeexercisetesting. The event rates for angina, angiographically determined restenosisand myocardial infarction increased over time, although there was no significant difference in their occurrence between those with a positive or negative exercisetest. Follow-up cardiac catheterization was performed at the discretion of the attending physician and was not a re quirement of the study. Angiographic restenosisrates are reported, realizing that only 63% of those with a negative exercisetest and 54% of those with a positive test underwent cardiac catheterization. For these reasons and also becauseof the small number of patients, the predictive accuracy of the exercise test for future cardiac events was not calculated. DISCUSSION Exercise testing continues to expand in concert with emerging advancesin the treatment of coronary artery disease.Many clinical questionsmay arise after ETCA at the time of hospital discharge,and exercisetesting at that time could have potential value in this area. Most studies describe the results of exercise tests performed at 17 days after FTCA. Some doubt has been cast on the safety of earlier testing by reports1s-17of acute coronary occlusion or myocardial infarction within minutes following exercise testing after successfulFTCA. The presentstudy demonstratesthe safety of symptom-limited predischarge exercise testing as early as 21 hours after successful PTCA in a clearly defined subset of patients. No exercise-related adverse events occurred among the 50 study patients as well as the 9 others who exercisedfor clinical reasons.These patients are repre sentativeof the type for whom an exercisetest might be used early after PTCA. Although exercise testing may MAY 15, 1992
well play a role in PTCA patients with a recent myocar- TABLE II Percentage of Patients Allowed to Return to Specific dial &&ion, such patients were excluded from this Activities* in a Given Time Frame: Initial Responses Compared study becausethe safety of symptom-limited testing 2 with Repeat Responses in Exercise (-) and No-Exercise Patients days after infarction has not been fully established.The 1 Exercise (-1 No-Exercise study patients represent a rather low risk group, although over one fourth had unstable angina before the Initial Repeat Initial Days Repeat procedure, one third underwent multivessel PTCA and Activity: Work (employed patients) had incomplete revascularization, and over one third of 27 44 62 41 30 lesions in the group were classified as type B. Patients 94 94 94 a14 a2 with lesionsdeemedunstable by the attending physician 15-21 94 94 92 a5 or angiographer, with evidenceof large dissection or re221 100 100 95 95 current abrupt closure, or both, during the angioplasty Activity: Shovel Snow procedure, were prudently excluded from this study. s7 3 8 0 0 Case reports of Dashls and Bedogni et ali7 included paa14 16 32 12 a tients similar to those in our study group. However, the 15-21 32 41 22 22 patient described by Nygaard et al16 had recently had 221 50 54 42 44 a myocardial infarction and developed abrupt closure Activity: Household Chores (includingvacuumingand lawn mowing) twice before exercise testing, and would have been ex17 19 46 16 20 cluded from our study. A common finding in all 3 case a14 71 84 69 67 reports was that all patients performed a vigorous level 15-21 95 92 91 94 of exercise.Of the 59 patients who performed symptom121 97 97 100 100 limited testing in our study, 41% reached >-Bruce stage Activity: Walkmg Exercise III and 13% exercised into stage IV. Considering this <7 74 88 75 65 high level of exercise, it is noteworthy that no vascular 8-14 98 100 97 100 complications occurred. 15-21 100 100 100 100 Beforeafter analysis of the physician management 221 responsesin this study demonstrate that a negative exActivity: Skiing ercise test after successful PTCA before hospital dis57 3 8 0 2 charge influences the physician to allow a return to 8-14 27 40 16 14 work and the performance of several activities earlier 15-21 53 67 45 41 than those who did not perform the exercise test. Two 221 87 89 90 88 prior studies22,23 have noted that the rate of return to Activity: Tennis work among employed patients after successfulPTCA 57 3 8 0 2 is less than might be expected. In the group of Fitzger8-14 29 47 29 27 ald et al,** 87% returned to work by 6-month follow-up, 15-21 68 79 z4 62 while in the PTCA Registry Study,23only 85% of 775 221 90 95 95 employed patients were working at 1.4 years’ follow-up. Activity: Bowling Dennis et a124concluded that exercisetesting and physi27 13 40 16 18 cian counseling yielded a 32% reduction in the convales8-14 84 90 a7 83 cenceperiod after myocardial infarction, thus leading to 15-21 95 97 95 95 an earlier return to work. Although our study did not 221 97 97 100 100 directly evaluate the actual time to return to work or *Only the 7 actwities that demonstrated a significantly different time shift index other activities, the data presented imply that exercise between exetase C-j and no-exerase groups are shown. Numbers in columns as read down represent cumulative percentage of patients I” testing early after PTCA affects the attitudes of physi- that group. Days = days after percutaneous transluminal coronary ang~oplasty; Exercise C-J = cians toward the performance of activities at an earlier patients I” theexerclsegmup without a” ischemic response duringexercise testing. date. If these attitudes are translated into action, such L
TABLE Ill Long-Term Follow-Up After Percutaneous Transluminal Coronary Angioplasty: Exercise Group (n = 46) Follow-Up Time
Angina Ml Cardiac catherization Restenosis No event or restenosis
1 Month
6 Months
18 Months
Exercise Test (+) t-1
Exercise Test (+) (-)
Exercise Test (+) (6)
27% 0% 31% 31% 64%
64% 0% 63% 55% 27%
9%
3%
91%
97%
p = not significant for comparisons of (+I YWSUS C-J at 1,6, and 18 months. MI = myocardial infarction; (+) = patients wth angina or ischemic ST depresson, (-) = patients without ischemia during exercise test (n = 35).
34% 3% 37% 31% 60%
49% 6% 54% 40% 43%
or both, during exercise test (n = 11);
EXERCISE TESTING AFTER CORONARY ANGIOPI-ASTY
1263
early testing may lead to a reduction in disability and recuperation time after FTCA. Predischarge exercise testing in this study did not yield discriminatory information regarding the likelihood of future restenosisor cardiac events.These data are limited by the small number of patients with a positive test, the availability of follow-up data on only 92% of subjects,and the fact that patients with definite angina after PTCA were excluded from our study. A positive test in our group most likely was due to residual coronary lesions that were not dilated. Study limitations: Becausethis report demonstrates no complications in only 50 study patients plus 9 others who underwent symptom-limited exercise testing early after PTCA, thesedata cannot be interpreted as conclusive, and cannot be extrapolated to all patients having undergone PTCA. Although these patients represent only a subsetof the total cohort of patients who presented for FTCA at our institution, this subsetis here clearly defined. Previous reports regarding safety of clinical exercisetesting yield complication rates that range from 0.8/10,000 in low-risk patients25to 2.4% in high-risk patients with arrhythmia. 26 Assuming our patients, as described, represent a lower risk group, a much larger prospectivetrial is neededto accurately assessthe safety of early testing. Becauseof these limitations, these data regarding safety must be interpreted with caution. The study demonstratesthat symptom-limited exercisetesting 1 to 3 days after FTCA is feasible and safe in ap propriately screenedpatients, and results of such testing can influence patient management.Thus, exercisetesting should not be performed routinely on all patients early after FTCA, but can be reasonablyand selectively used as an additional clinical tool, particularly in the activity prescription after coronary angioplasty. Acknowledgment: We are grateful to Kathleen McNiff of the Biostatics Laboratory at the Boston University School of Public Health for her assistancewith our statistics, and to Jane Foley for her valuable efforts in the preparation of this manuscript.
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plasty in multivessel disease: results of exercise stress testing. J Am Co/l Cardiol 1988;11:211-222. 6. Deligonul U, Vandormael MG, Shah Y, Galan K, Kern MJ, Chaitman BR. Prognostic value of early exercise stress testing after successful coronary angioplasty: importance of the degree of revascularization. Am Heart J 1989~117: 509-5 14. 7. Breisblatt WM. Weiland FL, Spaccavento LJ. Stress thallium-201 imaging after coronary angioplasty predicts restenosis and recurrent symptoms. J Am Co11 Cordial 1988;12:1199-1204. 8. Manyari DE, Knudtson M, Kooiber R, Roth D. Sequential thallium-201 myocardial perfusion studies after successful percutaneous transluminal coronary artery angioplasty: delayed resolution of exercise-induced scintigraphic abnormalities. Circulation 1988;77:86-95. 9. O’Keefe JH, Lapeyre AC, Holmes TR, Gibbons JR. Usefulness of early radionucleide angiography for identifying low-risk patients for late restenosis after percutaneous transluminal coronary angioplasty. Am J Cardiol 1988;61:51-54. 10. Breisblatt WM. Barnes JV, Weiland F, Spaccavento LJ. Incomplete revascularization in multivessel percutaneous transluminal coronary angioplasty: the role for stress thallium-201 imaging. J Am Co11 Cardiol 1988;11:1183-1190. il. Deligonul U, Vandormael MG, Younis LT. Chaitman BR. Prognostic signiticance of silent myocardial ischemia detected by early treadmill exercise after coronary angioplasty. Am J Cardiol 1989;64:1-5. 12. Bengston JR, Mark DD, Honan MB, Randall DS, Hinohara T, Stack R, Hlatky MA, Califf RM, Lee KL, Pryor DB. Detection of rcstenosis after elective percutaneous transluminal coronary angioplasty using the exercise treadmill teat. Am J Cardiol 1990,65:28-34. 13. Laarman G, Luitjen HE, VanZeyl LGPM, B&t KJ, Tijssen GJP, Serruys PW, DeFeyter PJ. Assessment of silent r&en&s and long-term follow up after successful angioplasty and single-vessel coronary artery disease: the value of quantitative exercise electrocardiography and quantitative coronary angiography. J Am Co11 Cardiol 1990;16:578-585. 14. American College of Cardiology/American Heart Association Task Force on assessment of cardiovascular procedures. Guidelines for exercise testing. J Am Coil Cardiol 1986;8:725-738. 15. Dash H. Delayed coronary occlusion after successful percutaneous transluminal coronary angioplasty: association with exercise te&ng. Am J Cardiol 1982;52:1143-1144. 16. Nygaard TW, Beller GA, Men&r RM, Gibson RS, Moeller CM, Bumwell LR. Acute coronary occlusion with exercise testing after initially successful corcnary angioplasty for acute myocardial infarction. Am JCardiol1986;57:687-688. 17. Bedogni F, LaVecchia L, Artier0 S, Castellani A, Vincenzi M. Acute corenary occlusion after recent coronary angioplasty - association with exercise and successful treatment with intracoronary thrombolysis. Chesl 1990;98:505-506. 18. ACC/AHA Task Force. Guidelines for percutaneous transluminal coronary angioplasty. A report from the American College of Cardiology/American Heart Association Task Force on awment of diagnostic and therapeutic cardiovascular procedures (subcommittee on percutaneous transluminal coronary angi* plasty). J Am Co11 Cardiol 1988;12:529-545. 19. Dorros G, Cowley MJ, Siipson J, Bentivoglio LG, Block P, Bourassa M, Detre K, Gwelin AJ, Gruntzig A, Kelsey SF, Kent KM, Mock MB, Mullin SM. Myler RK, Passamani ER, Stertzer SH, Williams DO. Percutaneous Transluminal Coronary Angioplasty: a report of complications for the National Heart, Lung, Blood Institute PTCA Registry. Circularion 1983;67:723-730. 20. Blair SN, Gibbons LW, Painter P, Pate RR, Taylor CB, Will J, exis. Guidelines for test administration. In: Guidelines for Exercise Testing and Prescription. American College of Sports Medicine. Philadelphia: Lea & Febiger, 19869-30. 21. Guiatt GH, Tugwell PS, Feeney DH, Drummond MF, Hayes RB. The role of beforeafter studies of therapeutic impact in the evaluation of diagnostic technologies. J Chron Dis 1986;39:295-304. 22. Fitzgerald ST, Becker DM, Seletano DD, Swank R. Brinker J. Return to work after percutaneous coronary transluminal angioplasty. Am J Cardiol 1989;64:1108-1112. 23. Holmes DR, VanRaden MJ, Reeder GS, Vlietstra RE, Jang GC, Kent KM, Vetrovec GW, Cowley MJ, Dorms G, Kelsey S, Detre KM, Mock MB. Return to work after coronary angioplasty: a report from the National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty Registry. Am J Cardiol 1984;53:48C-5lC. 24. Dennis C, Houston-Miller N, Scwartz RG, Ahn DK, Kraemer HZ, Gossard D, Juneau M, Tayler B, DeBusk RF. Early return to work after uncomplicated myocardial infarction - results of a randomized trial. JAMA 1988;260:214-220. 25. Gibbons L, Blair SN, Kohl HN, Cooper K. The safety of maximal exercise testing. Circulation 1989;80:84t-852. 26. Young DZ, Lampert S, Grayboys TB, Lawn B. Safety of maximal exercise testing in patients at high risk for ventricular arrhythmia. Circularion 1984; 70:184-191.
MAY 15, 1992
To evaluate both the safety and clinical use of predischarge symptom-limited exercise testing after successful uncomplicated percutaneous tranduminal coronary angtoplasty (PTCA), 199 patients were randomized to undergo exercise testing (n = 50) or no exercise testing (n = 90). There were no differences in clinical or angiographic characteristics between the groups. Exercise testing was performed 39 f 14 hours after PTCA. Patients who exercised achieved 71 f 12% of predicted maximal heart rate, wtth 38% reaching I stage III of the Bruce protocol. No patient in either group developed cardiac complications during 49 hour follow-up. Of the 11 patients with a positive test result, 92% had angiographically incomplete revascutartxatton. Attending physicians (n = 16) were questfoned both before and after exercise testing about when, after discharge, they would allow their pattent to perform each of 11 specific activtttes of daily living. Questttnnaires were administered to physfcians at stmilar time frames for patients in the no-exercise group. Comparfson of the responses between inttial and repeat questionnaires showed that patients in the exercise group (with a test result negative for ischemia) were allowed to perform 7 of 11 acttvtties, includtng return to work, earlier (p <0.09) than the no-exercise patients. These data indicate that in this welidefined group of patients, symptom-iimtted exercise testing early after PTCA appears to bs safe, and alters phystcian management in allowing patients with a negative test resutt to return to various activtttes at an earlier date. Such testing may be useful in counseting patients after PTCA. (AmJCardid 1992;69:1259-1264)
From the Department of Medicine and the Evans Memorial Department of Clinical Research, The University Hospital/Boston University Medical Center, Boston, Massachusetts. Manuscript received November 6,1991; revised manuscript received January 10,1992, and accepted January 11. Address for reprints: Gary J. Balady, MD, Section of Cardiology, The University Hospital, 88 East Newton Street, Boston, Massachusettso2118.
xercise testing is a widely used method employed in the managementof patientswith coronary artery diseaseand is particularly valuable in assessing cardiovascular status after the occurrence of a cardiac event or therapeutic intervention. Percutaneoustransluminal coronary angioplasty (PTCA) is a major modality of coronary revascularization with well over 200,000 procedures performed annually in the United States alone.’ Therefore, the issue of patient evaluation after successful PTCA is of growing importance. Exercise testing after PTCA has potential to yield useful information, such as the (1) assessmentof a patient’s functional ability for use in activity prescription; (2) establishment of the adequacy of revascularization, particularly in a patient in whom PTCA has beenperformed as an incomplete revascularization strategy; (3) assessment of symptoms such as chest pain or dyspnea after the procedure; and (4) prediction of future cardiac events, including restenosis. Previous studies regarding such testing have focused primarily on its value in assessing prognosis.*-l3 However, there is little information regarding the role of the exercisetest in patient management after angioplasty. Although exercise testing 17 days after PTCA has generally been consideredsafe,14 there are severalcasereports15-17 that document the occurrence of serious complications within minutes after exercisetesting has been performed early after PTCA. Therefore, the purpose of this study was to evaluate symptom-limited exercise testing before hospital discharge, as early as possibleafter successfulPTCA, in a well-defined population with regard to the safety of the procedure and its clinical utility.
E
METHOD8 An overview of the study methodsis outlined in Figure 1. A total of 160 consecutiveeligible patients were approached for enrollment into the study after undergoing successfulPTCA. Of these, 100 patients agreed to participate. Patients were deemedineligible from the study for any of the following reasons:(1) myocardial infarction within 3 weeks; (2) inability to exercise because of hemodynamic instability, neurologic or ortho pedic impairment; (3) unsuccessful coronary angioplasty or large intimal dissection,or both, after the procedure; (4) definite signs or symptomsof ischemia after PTCA (these patients were excluded from randomization becausethe developmentof ischemia after exercise testing was considereda study end point); and (5) femoral site vascular complication after PTCA including painful area, hematoma >3 mm, or pseudoaneurysm. EXERCISE TESTING AFTER CORONARY ANGIOPIASTY
1259
The 100 study patients were randomized into 2 (1) exercise group - consisting of 50 patients who performed symptom-limited exercise testing after PTCA before hospital discharge; and (2) no-exercise (control group) - 50 patients who did not perform the predischargeexercisetest after PTCA. Information was obtained regarding the patient’s age, sex, employment status, medications, angina1class, and history of previous myocardial infarction. Informed consent was obtained in accordance with the Institutional Review Board for Human Researchat the University Hospital/ Boston University Medical Center. and angiographii analysis: cor0MlywcW-Q All randomized patients underwent successfulPTCA in the cardiac catheterization laboratory at the University Hospital. This was defined as a change in lumen diameter of 220% and a residual stenosisof 150% in all attempted lesions without associated in-hospital death, myocardial infarction or emergency coronary bypass surgery. The narrowings were measuredby calipers in 2 orthogonal views. Before PTCA, all lesions were characterized into types A, B or C based on previously established criteria? type A lesionswere deemedto have the highest success/lowestrisk; type B were considered intermediate, and type C, the lowest success/highest risk. Intimal dissection after PTCA was defined as intima1 damage producing an intraluminal filling defect (tear), extravasation of contrast material or linear luminal density staining, and was graded from mild to severe according to previously described detinitions.i9 Revascularization after PTCA was “complete” if there was no remaining stenosisof 170% in a major coronary artery or branch (11.5 mm in diameter) and “incomplete” if there was such a residual stenosis.Revascularization was judged “adequate” if there was no remaining lesion of 170% in a vessel 11.5 mm in diameter that servedviable myocardium (indicated by the preservation of regional wall motion distal to a stenosison left ventriculography). Restenosiswas defined angiographitally by the presenceof 150% stenosisat the site of the previous PTCA. Exercise tosting: All 50 patients in the exercise group underwent symptom-limited exercise testing in groups:
METHODS PATIENTS
ELIGIBLE POST-PTCA
RANDOMIZEGOJb EXERCISE
(160)
REFUSED (60)
GROUPH (50) >EXERCISE GROUP’ (50) 1 1 l Clinical and angiographic data l Initial physician questionnaire
1 Symptom limited exercise test (BRUCE PROTOCOL) 1 l l l
1 No exercise 1
test
Repeat physician questionnaire 48 hour post-PTCA clinical follow-up 18 month clinical followup
FlGUREl.AlglIdh~theStUdyprOtOCd.Nunbershp8fmfhe8esrefartolhemmnberofpathtsin~
cabgoryasdetdlsdhthetext.PlCA=perahmwtransh---.
1260
THE AMERICAN JOURNAL OF CARDIOLOGY VOLUME 69
the exerciselaboratory at the University Hospital 1 to 3 days after PTCA before hospital discharge.Patients exercised while taking their usual medications, using either the standard Bruce (45 subjects)or modified Bruce protocol (5 subjects).2oThe protocol was selectedbased on the investigators’ (GJB or MLL) perception regarding the patient’s ability to ambulate. Exercise was terminated for any of the following reasons:moderate angina, definite ischemic ST-segmentdepression13 mm, significant fatigue, and complex ventricular ectopy or exertional hypotension. Heart rate, blood pressure and 1Zlead electrocardiogramswere obtained at rest, during each minute of exercise,at peak exerciseand during recovery. A positive responsewas defined as having either definite angina during testing or 11 mm of horizontal or downsloping ST-segmentdepression,or Il.5 mm of upsloping ST depressionat 0.08 secondafter the J point in 3 consecutivebeats of the samelead. Patients were observedin the hospital for a minimum of 2 hours after the test. Clinical follow up: All patients in both groups were contacted by telephone approximately 48 hours after hospital discharge to evaluate the occurrence of any clinical events including: angina, repeat hospitalization, myocardial infarction, vascular complication or death. Patients who exercisedwere contacted by telephone at 18 f 4 months after the exercise test to evaluate the occurrence of clinical events including angina, myocardial infarction, repeat coronary angiography or death. These data were supplemented with information obtained from chart review. Physician management assessment: The evaluation of patient managementafter PTCA in the exerciseand no-exercisegroups was conducted by use of a questionnaire (Appendix I) that was administered to the attending physician of each individual study patient. This questionnaire requestedinformation regarding the timing of patient discharge and the allowanceof 11 specific household or leisure activities. Inquiries regarding return to work were limited to those who were employed before PTCA. Physicians were asked to define the timing of their allowance of each activity in terms of days after hospital discharge according to the following choices: 1 to 7 days (score = l), 8 to 14 days (score = 2), 15 to 21 days (score = 3) after 21 days (score = 4) or “never” (score = 5). Identical questionnaires were verbally administered by the sameinvestigator (GJB or MLL) to each physician initially after the PTCA before the exercisetest results were disclosed,and again after the exercise test results were revealed. Questionnaires regarding patients in the no-exercise group were also administered twice at a similar time frame as for those in the exercise group. Repeat questionnaires were administered at a separate time period from the initial one without disclosure or reference to the previous responses.Comparisons between the initial and repeat responseswere used to determine the impact of the exercise test on management strategy using the “beforeafter” analysis method.21For easeof statistical comparison, differences between initial and repeat responses were reported as a time shift index. This was calculated by taking the difference in the mean time scores for MAY 15, 1992
APPENDtX I -
Physician Management Questionnaire
1) When do you plan to discharge the patient -days
from PTCA?
2) Do you plan any change of medications at this time? -(l) add _ (2) decrease _ (3) no change 3) When _ _ _ _ _
will you allow your patient to return to work? (1) l-7 days after discharge (2) 8-14 days after discharge (3) 15-21 days after discharge (4) After 21 days (5) Never
4) When _ _ _ _ _
will (1) (2) (3) (4) (5)
you allow your patient to drive? l-7 days after discharge 8-14 days after discharge 15-21 days after discharge After 21 days Never
6) When _ _ _ _ _
will (1) (2) (3) (4) (5)
you allow your patient to engage in sexual activity? l-7 days after discharge 8-14 days after discharge 15-21 days after discharge After 21 days Never
7) When will you allow your patient to perform household activities such as vacuuming or mowing the lawn? _ (1) l-7 days after discharge _ (2) 8-14 days after discharge _ (3) 15-21 days after discharge _ (4) After 21 days -(5) Never 8) If it were winter when would you allow the patient to shovel snow? _ (1) l-7 days after discharge _ (2) 8-14 days after discharge _ (3) 15-21 days after discharge _ (4) After 21 days _ (5) Never 9) When would you leisure activity? golf: -cl) _ _ _ -(5) bowling: _ _ _ _ _ walking: _ _ _ _ _ jogging: _ _ _ _ -(5) skiing: _ _ _ _ -(5) tennis: _ _ _ _ -(5)
allow your patient to participate in the following l-7days (2) 8-14 days (3) 15-2 1 days (4) After 21 days Never (1) l-7 days (2) 8-14 days (3) 15-2 1 days (4) After 2 1 days (5) Never (1) l-7 days (2) 8-14 days (3) 15-2 1 days (4) After 2 1 days (5) Never (1) l-7 days (2) 8-14 days (3) 15-21 days (4) After 21 days Never (1) l-7 days (2) 8-14 days (3) 15-21 days (4) After 2 1 days Never (1) l-7 days (2) 8-14 days (3) 15-21 days (4) After 21 days Never
1 TABLE I Exercise Test Responses
(n = 50)
Heart rate peak (beats/mm) % predicted maximal heart rate Rate-pressure product peak fbeats/min x mm Hg) Final exercise stage 5 Bruce stage I Bruce stage II Bruce stage Ill t Bruce stage IV No. of positive tests for angina or ischemic ST changes
I 120 k 21 71 k 12% 18.2 + 5.8 x lo3 13 18 13 6 11
(26%) (36%) (26%) (12%) (22%)
each activity between the initial and the repeat questionnaires. A “negative” time shift reflected the allowance of the activity at an earlier time frame from the initial response,while a “positive” time shift indicated the allowance of an activity at a later time frame. The time shifts were comparedbetweenthe exerciseand noexercisegroups using the non paired t test. StatistIcal analysis: Mean and standard deviations were calculated for all clinical and exercise test variables. Comparisons between groups were made using the non paired t test or chi-square evaluation. A probability level <0.05 was used to define statistical signilicance. RESULTS Patknl popubtion: Mean age of the 100 patients was 57 f 11 years, with 83% being men. All were taking medications at the time of FTCA including aspirin (lOO%), calcium channel antagonists (98%), /3 adrenergic-blocking agents (43%) and digoxin (8%). New York Heart Association class III or IV angina was reported in 48%, whereasunstable angina before PTCA was seen in 21%. Over one third of the patients had multivessel coronary artery disease and underwent multivessel FICA. Lesions were located with near equal distribution in the left anterior descending(38%), left circumflex (24%) and right coronary arteries (38%). The majority of lesions (61%) were classified as type A, whereas 33%were type B and 6% type C. Mean percentageof lumen diameter stenosisafter FTCA was 22 f 3%. Revascularization was deemed adequate in all patients, with most (70%) classified as “complete-adequate” and 30% as “incomplete-adequate.” When each of these characteristics were analyzed separately for the exercise group versusthe no-exercisegroup, there were no significant differences. However, more of the no-exercise group were employed (78%) comparedwith the exercise group (58%) (p <0.05). Small to moderate dissections were noted after PTCA in 5 patients (10%) in the exercise group compared to 6 (11%) in the noexercise group. Exercise te&Ingr The 50 patients in the exercise group underwent exercise testing approximately 38 f 14 hours (range 21 to 72 hours) after F’TCA. The results are listed in Table I. No patient was limited by leg pain at the catheter insertion site. There were 11 (22%) positive test results, with 7 demonstrating ischemic ST depressionwithout angina, 2 with ischemic ST depression and typical angina, and 2 with typical angina and no ischemic ST depression.Ten of 11 patients (92%) EXERCISE TESTING AFTER CORONARY ANGIOPIASN
1261
with a positive test responsehad incomplete-adequate revascularization. Conversely, of the 19 patients in the exercise group who had incomplete-adequaterevascularization, 10 (53%) had a positive exercise test response.However, there were no differencesin the extent of residual coronary artery diseaseor in the peak exercise variables achieved between those with a positive or a negative test result. Only 1 of 31 patients (3%) with completeadequate revascularization had a positive test. At a mean follow-up time of 51 f 25 hours after exercise testing, no patient in the exercise group demonstrated any complications, including the developmentor worsening of femoral area hematomas. However, at a similar follow-up time frame, 1 patient in the no-exercise group developeda femoral artery pseudoaneurysm at the catheterization site. Another 9 patients, who were originally excluded from randomization becauseof ischemic signs or symp toms after PTCA, underwent symptom-limited exercise testing at the request of their attending physician. Before exercise, 1 of these patients had a large dissection at the angioplasty site. Only 1 developed exercise-induced ischemic ST depression with angina while the other 8 test results were negative. None of these 9 patients developed any further angina or complications within 1 month after PTCA. Physkhmmagemdaftorpercutanaourtranslumind eoronuy B Initial and repeat manage-
ment questionnaireswere administered to 16 individual physicians regarding their respectivepatients enrolled in the study. Each managed an average of 6 (range 1 to 18) study patients. Discharge from the hospital was allowed within 2 days of PTCA in 90% of all patients and did not differ between groups. Comparison of the initial and repeat management responsesdemonstrated the time shift for allowance of 11 specific activities to be significantly “earlier” (p <0.05) in only 3 categories (return to work, snow-shoveling and skiing) in the exercise group versus the noexercisegroup. When the time shift indexes for patients
sr
1.
.
Walking
Exercise
Bowling 1.
Shoveling .
House
Snow Chores
Work
I
b -0.4
-0.3
-0.2
Earlier
-0.1
0
0.1
0.2
I 0.3
Later TIME SHIFT INDEX
PmuRE2conprbanefthetlmeddfthdex(seetext)for pdhnt8hexer&egplpwHhenegeUveexerdsetest(open b8fe)velwu8theno-exwdsegroqb(~b8l%)foreedl~tydqhyad.*p
THE AMERICAN JOURNAL OF CARDIOLOGY VOLUME 69
in the exercisegroup with a positive ischemic response (n = 11) were compared with those having a negative response(n = 39) there was a trend toward the allowance of each activity to be performed earlier in those without ischemia, although this difference in time shift between groups did not reach statistical significance. Accordingly, the time shift indexes for exercise group patients without an ischemic test response (n = 39) were compared to those of the no-excercisegroup. Figure 2 shows the shift in time frame responseto be significantly earlier in 7 of 11 activities for patients with a negative exercisetest. Theseactivities included return to work, household chores (including lawn mowing and vacuuming), snow shoveling, walking for exercise,tennis, skiing and bowling. However, the time shift was not different between groups in 4 activities includiig driving, sexual activity, golf, and jogging. Table II outlines these responsesand showsthat the time frame shift for the allowance of any particular activity could occur at any 1 of the 5 time frame choices for each activity in each patient. Long-term follow-up: Long-term follow-up data were pursued for exercisegroup patients to determine if the exercisetest data were predictive of future cardiac events after hospital discharge. Successful follow-up was obtained in 46 patients (92%) at 18 f 4 months after PTCA, and the results are outlined in Table III. All 4 patients who were lost to follow-up had negative results on predischargeexercisetesting. The event rates for angina, angiographically determined restenosisand myocardial infarction increased over time, although there was no significant difference in their occurrence between those with a positive or negative exercisetest. Follow-up cardiac catheterization was performed at the discretion of the attending physician and was not a re quirement of the study. Angiographic restenosisrates are reported, realizing that only 63% of those with a negative exercisetest and 54% of those with a positive test underwent cardiac catheterization. For these reasons and also becauseof the small number of patients, the predictive accuracy of the exercise test for future cardiac events was not calculated. DISCUSSION Exercise testing continues to expand in concert with emerging advancesin the treatment of coronary artery disease.Many clinical questionsmay arise after ETCA at the time of hospital discharge,and exercisetesting at that time could have potential value in this area. Most studies describe the results of exercise tests performed at 17 days after FTCA. Some doubt has been cast on the safety of earlier testing by reports1s-17of acute coronary occlusion or myocardial infarction within minutes following exercise testing after successfulFTCA. The presentstudy demonstratesthe safety of symptom-limited predischarge exercise testing as early as 21 hours after successful PTCA in a clearly defined subset of patients. No exercise-related adverse events occurred among the 50 study patients as well as the 9 others who exercisedfor clinical reasons.These patients are repre sentativeof the type for whom an exercisetest might be used early after PTCA. Although exercise testing may MAY 15, 1992
well play a role in PTCA patients with a recent myocar- TABLE II Percentage of Patients Allowed to Return to Specific dial &&ion, such patients were excluded from this Activities* in a Given Time Frame: Initial Responses Compared study becausethe safety of symptom-limited testing 2 with Repeat Responses in Exercise (-) and No-Exercise Patients days after infarction has not been fully established.The 1 Exercise (-1 No-Exercise study patients represent a rather low risk group, although over one fourth had unstable angina before the Initial Repeat Initial Days Repeat procedure, one third underwent multivessel PTCA and Activity: Work (employed patients) had incomplete revascularization, and over one third of 27 44 62 41 30 lesions in the group were classified as type B. Patients 94 94 94 a14 a2 with lesionsdeemedunstable by the attending physician 15-21 94 94 92 a5 or angiographer, with evidenceof large dissection or re221 100 100 95 95 current abrupt closure, or both, during the angioplasty Activity: Shovel Snow procedure, were prudently excluded from this study. s7 3 8 0 0 Case reports of Dashls and Bedogni et ali7 included paa14 16 32 12 a tients similar to those in our study group. However, the 15-21 32 41 22 22 patient described by Nygaard et al16 had recently had 221 50 54 42 44 a myocardial infarction and developed abrupt closure Activity: Household Chores (includingvacuumingand lawn mowing) twice before exercise testing, and would have been ex17 19 46 16 20 cluded from our study. A common finding in all 3 case a14 71 84 69 67 reports was that all patients performed a vigorous level 15-21 95 92 91 94 of exercise.Of the 59 patients who performed symptom121 97 97 100 100 limited testing in our study, 41% reached >-Bruce stage Activity: Walkmg Exercise III and 13% exercised into stage IV. Considering this <7 74 88 75 65 high level of exercise, it is noteworthy that no vascular 8-14 98 100 97 100 complications occurred. 15-21 100 100 100 100 Beforeafter analysis of the physician management 221 responsesin this study demonstrate that a negative exActivity: Skiing ercise test after successful PTCA before hospital dis57 3 8 0 2 charge influences the physician to allow a return to 8-14 27 40 16 14 work and the performance of several activities earlier 15-21 53 67 45 41 than those who did not perform the exercise test. Two 221 87 89 90 88 prior studies22,23 have noted that the rate of return to Activity: Tennis work among employed patients after successfulPTCA 57 3 8 0 2 is less than might be expected. In the group of Fitzger8-14 29 47 29 27 ald et al,** 87% returned to work by 6-month follow-up, 15-21 68 79 z4 62 while in the PTCA Registry Study,23only 85% of 775 221 90 95 95 employed patients were working at 1.4 years’ follow-up. Activity: Bowling Dennis et a124concluded that exercisetesting and physi27 13 40 16 18 cian counseling yielded a 32% reduction in the convales8-14 84 90 a7 83 cenceperiod after myocardial infarction, thus leading to 15-21 95 97 95 95 an earlier return to work. Although our study did not 221 97 97 100 100 directly evaluate the actual time to return to work or *Only the 7 actwities that demonstrated a significantly different time shift index other activities, the data presented imply that exercise between exetase C-j and no-exerase groups are shown. Numbers in columns as read down represent cumulative percentage of patients I” testing early after PTCA affects the attitudes of physi- that group. Days = days after percutaneous transluminal coronary ang~oplasty; Exercise C-J = cians toward the performance of activities at an earlier patients I” theexerclsegmup without a” ischemic response duringexercise testing. date. If these attitudes are translated into action, such L
TABLE Ill Long-Term Follow-Up After Percutaneous Transluminal Coronary Angioplasty: Exercise Group (n = 46) Follow-Up Time
Angina Ml Cardiac catherization Restenosis No event or restenosis
1 Month
6 Months
18 Months
Exercise Test (+) t-1
Exercise Test (+) (-)
Exercise Test (+) (6)
27% 0% 31% 31% 64%
64% 0% 63% 55% 27%
9%
3%
91%
97%
p = not significant for comparisons of (+I YWSUS C-J at 1,6, and 18 months. MI = myocardial infarction; (+) = patients wth angina or ischemic ST depresson, (-) = patients without ischemia during exercise test (n = 35).
34% 3% 37% 31% 60%
49% 6% 54% 40% 43%
or both, during exercise test (n = 11);
EXERCISE TESTING AFTER CORONARY ANGIOPI-ASTY
1263
early testing may lead to a reduction in disability and recuperation time after FTCA. Predischarge exercise testing in this study did not yield discriminatory information regarding the likelihood of future restenosisor cardiac events.These data are limited by the small number of patients with a positive test, the availability of follow-up data on only 92% of subjects,and the fact that patients with definite angina after PTCA were excluded from our study. A positive test in our group most likely was due to residual coronary lesions that were not dilated. Study limitations: Becausethis report demonstrates no complications in only 50 study patients plus 9 others who underwent symptom-limited exercise testing early after PTCA, thesedata cannot be interpreted as conclusive, and cannot be extrapolated to all patients having undergone PTCA. Although these patients represent only a subsetof the total cohort of patients who presented for FTCA at our institution, this subsetis here clearly defined. Previous reports regarding safety of clinical exercisetesting yield complication rates that range from 0.8/10,000 in low-risk patients25to 2.4% in high-risk patients with arrhythmia. 26 Assuming our patients, as described, represent a lower risk group, a much larger prospectivetrial is neededto accurately assessthe safety of early testing. Becauseof these limitations, these data regarding safety must be interpreted with caution. The study demonstratesthat symptom-limited exercisetesting 1 to 3 days after FTCA is feasible and safe in ap propriately screenedpatients, and results of such testing can influence patient management.Thus, exercisetesting should not be performed routinely on all patients early after FTCA, but can be reasonablyand selectively used as an additional clinical tool, particularly in the activity prescription after coronary angioplasty. Acknowledgment: We are grateful to Kathleen McNiff of the Biostatics Laboratory at the Boston University School of Public Health for her assistancewith our statistics, and to Jane Foley for her valuable efforts in the preparation of this manuscript.
REFERENCES 1. American Heart Association - 1991 Heart and Stroke Facts. Dallas, Texas. 1990. 2. Shall JM, Chaitman BR, David PR, Dupras G, Brevem G, Val PG, Crepau J, Lesperance J, Bourassa MG. Exercise electrocardiography and myocardial scintigraphy in the serial evaluation of the results of percutaneous transhnninal core nary angioplasty. Circularion 1982;66:380-390. 3. Rosing D, VanRaden MJ, Mincemoyer RM, Bonow RO, Bourassa MG, David PR, Ewels CJ, Detre KM, Kent KM. Exercise electrocardiographic and functional responses after percutaneous transluminal coronary angioplasty. Am J Cwdiol 1984;53:36C-41C. 4. Wijens W, Sexruys PW, Reiber JHC, DeFeyter PJ, Vandenbrand M, Simoons ML, Hugenholtz PG. Early detection of restenosis after successful percutaneous transluminal coronary angioplasty by exercise-redistribution thallium scintigraphy. Am J Cardiol 1985;55:357-361. 5. Thomas ES, Most AS, Williams DO. Objective assessment of coronary angie
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