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Long-term efficacy of percutaneous transluminal coronary angioplasty (PTCA): Report from the national heart, lung, and blood institute PTCA registry
Long-Term Efficacy of PercutaneousTransluminalCoronary Angioplasty (PTCA): Report from the National Heart, Lung, and Blood InstitutePTCA Registry KENNETH M. KENT, MD, LAMBERTO G. BENTIVOGLIO, MD, PETER C. BLOCK, MD, MARTIAL G. BOURASSA,
MD, MICHAEL J. COWLEY, MD, GERALD DORROS, MD,
KATHERINE M. DETRE, MD, DrPH, ARTHUR J. GOSSELIN, MD, ANDREAS R. GRUENTZIG, MD, SHERYL F. KELSEY, PhD, MICHAEL B. MOCK, MD, SUZANNE M. MULLIN, RN, MPH, EUGENE R. PASSAMANI,
MD,
RICHARD K. MYLER, MD, JOHN SIMPSON, MD, SIMON H. STERTZER, MD, MARK J. VAN RADEN, MA, and DAVID 0. WILLIAMS, MD
The NHLBI PTCA Registry has collected data from 3,079 patients who underwent PTCA at 105 centers from September 1977 through September 1981 that document the initial risks and benefits of PTCA. A subgroup of 2,272 patients at 65 centers was chosen to examine the long-term effects of PTCA (97% follow-up). All patients were followed for 1 year, 191 for 3 years and 57 for 4 years. Initial success occurred in 1,397 (61% ), and 72 % remained improved at 1 year with no further procedures; during the first year of follow-up, 14% had repeat PTCA, 12% had CABG, 3% had Ml and 1.6% died, After
1 year, 67% were asymptomatic; of these, 52% had no other procedure, 7% had a second PTCA and 8 % had CABG. Follow-up at 2 to 4 years was similar except that there were few repeat PTCA or CABG procedures after 1 year. The annual mortality rate after PTCA in patients with l-vessel diseases was less than 1% per year and with multivessel CAD, 3 % per year. Thus, successful PTCA alone results in sustained improvement in 84% of patients; 59% were asymptomatic ( 12% had repeat PTCA). PTCA offers extended effective therapy in selected patients with CAD. (Am J Cardiol 1984;53:27C-3lC)
The effectiveness of PTCA depends not only on the initial risks and benefits of the procedure, but also on the sustained patency of the angioplasty site, amelioration of signs and symptoms of myocardial ischemia and a low risk of complications of CAD, such as MI and death during the years after the procedure. The NHLBI PTCA Registry provided the means of collecting data on the initial procedure in 3,079 patients at 105 clinical centers and virtually complete follow-up in 2,272 patients who underwent the procedure at 65 of the 105 centers. These follow-up data have allowed us to examine the ability of this nonoperative technique to achieve the objectives of therapy, that is, sustained amelioration of symptoms at an acceptable risk to the patients.
Methods Attempts were made in 1982 to contact all patients who underwent PTCA from September 1977 to September 1981 at 65 sites. Table I is a list of the information obtained from each patient contacted. Results of exercise tests and follow-up angiograms were available in some subsets of patients; however, this report deals only with data collected in all patients. Patients were contacted within a 2-month window of the anniversary date of their PTCA (1 month before to 1 month after the anniversary date). When ordinary procedures were unsuccessful in locating the patients, a professional organization, Equifax, was employed. The patients were questioned as to the need for medication, repeat PTCA or CABG. “Symptom-free” referred to no chest pain. MI was documented by contacting the patient’s physician. Successful PTCA is defined as a 20% or more decrease in arterial stenosis and the absence of MI, death or CABG during initial hospitalization. A cohort analysis was performed to examine symptoms at final follow-up contact. Life-table survival analysis was used to examine time to death, to MI, to CABG and to repeat
Address for reprints: Kenneth M. Kent, MD, Director, Cardiac Catheterization Laboratories, Georgetown University Medical Center, 3800 Reservoir Road NW, Washington, D.C. 20007. 27C
28C
LONGTERM
TABLE I
EFFICACY
OF PTCA
Minimum Information Obtained at Follow-Up Anniversary
PTCA were examined. Patients were divided into 4 cohorts according to when their first PTCA was performed, that is, 1,2,3 or 4 years before follow-up contact. The earlier the procedure was performed, the longer the follow-up time. Successful PTCA was performed in 906 of 1,418 patients (64%) at 1 year, 349 of 606 patients (58%) at 2 years, 108 of 191 patients (57%) at 3 years and 34 of 57 patients (60%) at 4 years. Within the cohorts, patients with initially successful procedures were further divided into groups according to events during the follow-up (Table IIA). These results indicate that 72% of the patients in the later cohort had only 1 PTCA with no subsequent events. In the earlier cohorts, the corresponding percentages are, respectively, 70.1, 69.0 and 72.7. In the latest cohort, 11.7% of the patients had a repeat PTCA. The percentage of patients who are symptom-free as well as having no events or only repeat PTCA after an initially successful PTCA are presented by cohort in Table IIB. In the l-year cohort, 52% of patients had no events and are symptom-free 1 year after PTCA. If added to that are the 7% of patients who had repeat PTCA but no other event, and are symptom-free at 1 year, the total symptom-free rate is 59%. Those who remained stable in the 2-year cohort include the 48% who had no event within 2 years of an initially successful procedure and were symptom-free plus those 8.4% who had only repeat PTCA and were symptom-free at 2 years after the initially successful first PTCA, for a total of 56%. For the 3- and $-year cohorts, the total sustained symptom-free rates are 64 and 67%, respectively. The numbers of patients within the 4 cohorts with 1, 2, 3 and 4 years of follow-up, re-
1. Do you have angina (chest pain)? Please check the category that most closely describes the frequency of your chest pain: no pain now; pain several times per week; pain less than once a week; pain once a day or more. 2. Are you taking nitroglycerin for angina (chest pain)? 3. Compared with that before your first balloon procedure, is your chest pain presently: improved; about the same; worse? 4. Since your first balloon procedure, have you: been hospitalized for chest pain; had a heart attack (myocardial infarction); had coronary bypass surgery; had additional balloon procedures? 5. Present employment: full-time; part-time; retired (you discontinued working upon reaching retirement age as opposed to quitting because of either a physician’s advice or incapacitation); medically retired (you were forced to stop working before retirement age because of cardiac symptoms, whether by your choice or on your physician’s recommendation); homemaker; other. Please list your present occupation and job title or the one you had before retiring. 6. Typical daily recreation or physical activity level during the last month: strenuous. moderate. mild or sedentarv.
PTCA. The Mantel-Haenszel chi-square test was used for comparison
between
survival
curves.
Results During the final year of follow-up (October 1, 1981, to September 30,1982), data were obtained for 2,198 of the 2,272 patients (Table I). Vital status and information about MI and CABG were available in an additional 36 patients, so that there are 2,234 patients for survival analysis. Effects of PTCA on symptoms: To determine the effects of successful angioplasty, the symptomatic status and subsequent events in patients who had successful TABLE IIA
Follow-Up Status at Final-Year Report*: Patients with Successful Percutaneous Transluminal Coronary Angioplasty (n = 1,397) l-Year Cohort (PTCA between lo/80 and 9181) (n = 906)
Alive No repeat PTCA, CABG or Ml Repeat PTCA, no CABG or Ml CABG but no Ml Ml Dead Lost to follow-up l
2-Year Cohort (PTCA between 10179 and 9180) (n = 349)
3-Year Cohort (PTCA between lo/78 and 9/79) (n = 108)
4-Year Cohort (PTCA before 10178) (n = 34)
n
%
n
%
n
%
n
%
683 104 100 30 14 20
72.0 11.7 11.3 3.4 1.6
235 35 45 13 7 14
70.1 10.4 13.4 3.9 2.1
69 10 11 7 3 8
69.0 10.0 11.0 7.0 3.0
24 F,
72.7 3.0 18.2 3.0 3.0
1 1 1
October 1, 1981, through September 30, 1982.
TABLE IIB
Symptom-Free Status at Final-Year Report l: Patients with Successful Percutaneous Transluminal Coronary Angioplasty l-Year Cohort (PTCA between lo/80 and 9181) (n = 906)
Alive and symptom-free No repeat PTCA, CABG or MI Repeat PTCA. no CABG or Ml * October 1, 1981, through September 30, 1982.
2-Year Cohort (PTCA between lo/79 and 9/80) (n = 349)
3-Year Cohort (PTCA between lo/78 and 9/79) (n = 108)
4-Year Cohort (PTCA before 10/78) (n = 34)
n
%
n
%
n
%
n
%
463 62
52.3 7.0
159 28
47.5 8.4
54 10
54.0 10.0
22 0
66.7 0.0
June
spectively, who remained symptom-free were constant. Figure 1 shows the l-year cohorts and the subset of those patients who were symptom-free at 1 year. Repeat PTCA: Of the 1,397 patients who had a successful procedure, 199 (14%) had a repeat PTCA during the first year after the procedure. In most patients, this repeat procedure involved the same lesion initially dilated, although in some patients, other lesions, were attempted during the second procedures. Few repeat procedures were performed after the first, year (Fig. 2). CABG during follow-up: During the first year after an initially successful PTCA, 12% of patients underwent CABG. Failure of an initially successful PTCA and the need for CABG were probably due to restenosis in some patients, and repeat PTCA was not attempted. Undoubtedly, CABG was recommended because of restenosis after a second PTCA in some patients. The reasons for CABG are not available, but CABG was not primarily confined to the first year after initial PTCA, as was repeat PTCA. The proportion of patients with multivessel disease who had CABG within 1 year after PTCA was 16.4% and
15, 1984
THE AMERICAN JOURNAL OF CARDIOLOGY Volume 53
29c
within 2 years after PTCA, 21.4% (Fig. 3). For l-vessel disease, the cumulative rates of CABG were 10.4% at 1 year and 12.1% at 2 years. Myocardial infarction: After hospital discharge 2.79% of patients with an initially successful PTCA sustained clinically apparent, MI during the first year aft.er PTCA. No attempt was made t,o assess the severity of the infarction, that is, transmural vs nontransmural, or the cause, that is, restenosis, occlusion of a vessel in which angioplasty was not performed, and so forth. However, hospitalization was documented in all cases. The frequency of MI in the first year after PTCA was similar in patients with l-vessel and multivessel disease (Table III); in subsequent years, patients with multivessel disease had a greater incidence of MI. Nonfatal MI occurred less frequently in patients who had successful PTCA (Fig. 4). Mortality: A Death Review Committee reviewed available information on the circumstances surrounding the deaths. Sufficient information was available to be certain that 8 patients died from noncardiac causes, and those patients are excluded from this analysis. Therefore, 36 patients died from cardiac causes. Forty-four of 2,272 patients died after discharge from the hospital. In 20 patients who died from cardiac or unknown causes during the follow-up period, the initial PTCA was successful. In the remaining 16 patients who died from cardiac causes, the initial PTCA was unsuccessful.
FIGURE 1. One-year follow-up of 1,379 patients who had initially successful PTCA. Seventy-two percent of these patients were symptom-free, 14% had repeat PTCA and 12% had CABG. The other 2 % had an MI or died. Stippled areas indicated proportion of patients who have no symptoms.
0
I
I
I
1
2
3
YEARS FIGURE 3. Number of patients whose condition was stable 1 to 3 years after an initially successful PTCA procedure without CABG. All pts = all 1,397 patients; MVD = multivessel disease; SVD = single-vessel disease.
TABLE III
Myocardial Infarction During Follow-Up Period by Vessel Disease in Patients with Initially Successful Percutaneous Transluminal Coronary Angioplasty l-Vessel Disease (n = 1,115)
I 0
I 2
1
I
3
YEARS FIGURE 2. Number of patients whose condition was stable without repeat PTCA 1 to 3 years after an initially successful procedure.
Time (yr) Since PTCA
Multivessel Disease (n = 282)
cum n
cum %
cum n
cum %
1
30
2.75
11
2.94
:
37 39
3.47 4.53
14 16
5.91 7.98
cum = cumulative.
3oc
LONG-TERM EFFICACY OF PTCA
Data were examined for predictors of late cardiac death in the hospital as well as in the follow-up period. The most important predictor of late mortality was left main CAD (p
or a subsequent hospitalization (Fig. 6). However, mortality was greater when PTCA was unsuccessful and no subsequent surgery was performed. Discussion The NHLBI PTCA Registry has provided informaction on the initial risks and benefits to the patient. Fortunately, a large subset of patients undergoing initial PTCA had been followed up carefully, and 97% of consecutive patients who had PTCA at 1 of 65 centers from 1977 to 1980 were contacted on the first through fourth anniversary of their initial procedure. This data base of 2,272 patients provides valuable information on the 100
l
=-----Q
(1.1)
(3.2)
. SVD o MVD A LM
80
0 Successful (1397) l All Patients (2272)
;I
I 1
2
YEARS FIGURE 5. Late cardiac deaths in patients after PTCA. LM = left main CAD; other abbreviations as in Figure 3.
1
I
1
I 2
YEARS FIGURE 4. Nonfatal MI in all patients after PTCA attempts and when PTCA was successful.
s
$0 TABLE
IV
Predictors of Mortality in Patients Undergoing Percutaneous Transluminal Coronary Angioplasty
Late cardiac deaths Left main disease (p60 years
5 %
Successful Unsuccessful -Surgery A Unsuccessful-No Surgery 0
l
i______lL__..i
2
YEARS
FIGURE 6. Late cardiac deaths in patients in whom PTCA was successful and those in whom it was not but in whom CABG was performed. The mortality rate in these groups was similar. In patients who had unsuccessful PTCA but had no CABG, the mortality rate was higher.
June15.
long-term effects of this procedure. Almost threefourths of the patients who had an initially successful procedure needed no further procedure during an average of 1.5 years of follow-up. Approximately half the patients remained in stable condition and symptom-free after the initial PTCA. This was the case in each cohort. Thus, on cross-sectional examination, about half the patients were event-free and symptom-free whether the PTCA had been performed 1,2,3 or 4 years previously. Because almost three-fourths the patients were classified as having severe or unstable angina before PTCA, the procedure itself was effective in ameliorating symptoms and signs of myocardial ischemia in approximately half these symptomatic patients. Almost all of the repeat PTCAs were performed in the first year after the initial procedure (Fig. 2). CABG was performed in 12% of the patients during the first year. The cumulative percentage increased to 14,16 and 18% in the second through fourth years after the initial PTCA. The reason these patients underwent CABG is unclear because in most centers restenosis is routinely treated by a second PTCA and not a CABG.
1984
THE AMERICAN JOURNAL OF CARDOLOGY
Volume 53
3%
Repeat PTCA may have been unavailable or not an alternative for other reasons. Furthermore, CABG was usually recommended in patients in whom restenosis developed after the second PTCA. Again, the requirement for CABG is not limited to the first year after PTCA, but continues at a slow rate in subsequent years. Patients with multivessel disease required subsequent operation more frequently than did patients with Ivessel disease. The mortality rate of patients undergoing PTCA after discharge from the hospital is small. Because most patients had l-vessel disease, they were considered a very low risk population. This proved to be the case, and the mortality in the first through fourth years after PTCA was approximately 1% per year in patients with l-vessel disease. Important predictors of late death were multivessel and left main CAD, either of which predicted a relatively high risk group during the years subsequent to a PTCA attempt. Another relatively high risk group were patients who had unsuccessful PTCA and were subsequently managed with CABG.
MD, MICHAEL J. COWLEY, MD, GERALD DORROS, MD,
KATHERINE M. DETRE, MD, DrPH, ARTHUR J. GOSSELIN, MD, ANDREAS R. GRUENTZIG, MD, SHERYL F. KELSEY, PhD, MICHAEL B. MOCK, MD, SUZANNE M. MULLIN, RN, MPH, EUGENE R. PASSAMANI,
MD,
RICHARD K. MYLER, MD, JOHN SIMPSON, MD, SIMON H. STERTZER, MD, MARK J. VAN RADEN, MA, and DAVID 0. WILLIAMS, MD
The NHLBI PTCA Registry has collected data from 3,079 patients who underwent PTCA at 105 centers from September 1977 through September 1981 that document the initial risks and benefits of PTCA. A subgroup of 2,272 patients at 65 centers was chosen to examine the long-term effects of PTCA (97% follow-up). All patients were followed for 1 year, 191 for 3 years and 57 for 4 years. Initial success occurred in 1,397 (61% ), and 72 % remained improved at 1 year with no further procedures; during the first year of follow-up, 14% had repeat PTCA, 12% had CABG, 3% had Ml and 1.6% died, After
1 year, 67% were asymptomatic; of these, 52% had no other procedure, 7% had a second PTCA and 8 % had CABG. Follow-up at 2 to 4 years was similar except that there were few repeat PTCA or CABG procedures after 1 year. The annual mortality rate after PTCA in patients with l-vessel diseases was less than 1% per year and with multivessel CAD, 3 % per year. Thus, successful PTCA alone results in sustained improvement in 84% of patients; 59% were asymptomatic ( 12% had repeat PTCA). PTCA offers extended effective therapy in selected patients with CAD. (Am J Cardiol 1984;53:27C-3lC)
The effectiveness of PTCA depends not only on the initial risks and benefits of the procedure, but also on the sustained patency of the angioplasty site, amelioration of signs and symptoms of myocardial ischemia and a low risk of complications of CAD, such as MI and death during the years after the procedure. The NHLBI PTCA Registry provided the means of collecting data on the initial procedure in 3,079 patients at 105 clinical centers and virtually complete follow-up in 2,272 patients who underwent the procedure at 65 of the 105 centers. These follow-up data have allowed us to examine the ability of this nonoperative technique to achieve the objectives of therapy, that is, sustained amelioration of symptoms at an acceptable risk to the patients.
Methods Attempts were made in 1982 to contact all patients who underwent PTCA from September 1977 to September 1981 at 65 sites. Table I is a list of the information obtained from each patient contacted. Results of exercise tests and follow-up angiograms were available in some subsets of patients; however, this report deals only with data collected in all patients. Patients were contacted within a 2-month window of the anniversary date of their PTCA (1 month before to 1 month after the anniversary date). When ordinary procedures were unsuccessful in locating the patients, a professional organization, Equifax, was employed. The patients were questioned as to the need for medication, repeat PTCA or CABG. “Symptom-free” referred to no chest pain. MI was documented by contacting the patient’s physician. Successful PTCA is defined as a 20% or more decrease in arterial stenosis and the absence of MI, death or CABG during initial hospitalization. A cohort analysis was performed to examine symptoms at final follow-up contact. Life-table survival analysis was used to examine time to death, to MI, to CABG and to repeat
Address for reprints: Kenneth M. Kent, MD, Director, Cardiac Catheterization Laboratories, Georgetown University Medical Center, 3800 Reservoir Road NW, Washington, D.C. 20007. 27C
28C
LONGTERM
TABLE I
EFFICACY
OF PTCA
Minimum Information Obtained at Follow-Up Anniversary
PTCA were examined. Patients were divided into 4 cohorts according to when their first PTCA was performed, that is, 1,2,3 or 4 years before follow-up contact. The earlier the procedure was performed, the longer the follow-up time. Successful PTCA was performed in 906 of 1,418 patients (64%) at 1 year, 349 of 606 patients (58%) at 2 years, 108 of 191 patients (57%) at 3 years and 34 of 57 patients (60%) at 4 years. Within the cohorts, patients with initially successful procedures were further divided into groups according to events during the follow-up (Table IIA). These results indicate that 72% of the patients in the later cohort had only 1 PTCA with no subsequent events. In the earlier cohorts, the corresponding percentages are, respectively, 70.1, 69.0 and 72.7. In the latest cohort, 11.7% of the patients had a repeat PTCA. The percentage of patients who are symptom-free as well as having no events or only repeat PTCA after an initially successful PTCA are presented by cohort in Table IIB. In the l-year cohort, 52% of patients had no events and are symptom-free 1 year after PTCA. If added to that are the 7% of patients who had repeat PTCA but no other event, and are symptom-free at 1 year, the total symptom-free rate is 59%. Those who remained stable in the 2-year cohort include the 48% who had no event within 2 years of an initially successful procedure and were symptom-free plus those 8.4% who had only repeat PTCA and were symptom-free at 2 years after the initially successful first PTCA, for a total of 56%. For the 3- and $-year cohorts, the total sustained symptom-free rates are 64 and 67%, respectively. The numbers of patients within the 4 cohorts with 1, 2, 3 and 4 years of follow-up, re-
1. Do you have angina (chest pain)? Please check the category that most closely describes the frequency of your chest pain: no pain now; pain several times per week; pain less than once a week; pain once a day or more. 2. Are you taking nitroglycerin for angina (chest pain)? 3. Compared with that before your first balloon procedure, is your chest pain presently: improved; about the same; worse? 4. Since your first balloon procedure, have you: been hospitalized for chest pain; had a heart attack (myocardial infarction); had coronary bypass surgery; had additional balloon procedures? 5. Present employment: full-time; part-time; retired (you discontinued working upon reaching retirement age as opposed to quitting because of either a physician’s advice or incapacitation); medically retired (you were forced to stop working before retirement age because of cardiac symptoms, whether by your choice or on your physician’s recommendation); homemaker; other. Please list your present occupation and job title or the one you had before retiring. 6. Typical daily recreation or physical activity level during the last month: strenuous. moderate. mild or sedentarv.
PTCA. The Mantel-Haenszel chi-square test was used for comparison
between
survival
curves.
Results During the final year of follow-up (October 1, 1981, to September 30,1982), data were obtained for 2,198 of the 2,272 patients (Table I). Vital status and information about MI and CABG were available in an additional 36 patients, so that there are 2,234 patients for survival analysis. Effects of PTCA on symptoms: To determine the effects of successful angioplasty, the symptomatic status and subsequent events in patients who had successful TABLE IIA
Follow-Up Status at Final-Year Report*: Patients with Successful Percutaneous Transluminal Coronary Angioplasty (n = 1,397) l-Year Cohort (PTCA between lo/80 and 9181) (n = 906)
Alive No repeat PTCA, CABG or Ml Repeat PTCA, no CABG or Ml CABG but no Ml Ml Dead Lost to follow-up l
2-Year Cohort (PTCA between 10179 and 9180) (n = 349)
3-Year Cohort (PTCA between lo/78 and 9/79) (n = 108)
4-Year Cohort (PTCA before 10178) (n = 34)
n
%
n
%
n
%
n
%
683 104 100 30 14 20
72.0 11.7 11.3 3.4 1.6
235 35 45 13 7 14
70.1 10.4 13.4 3.9 2.1
69 10 11 7 3 8
69.0 10.0 11.0 7.0 3.0
24 F,
72.7 3.0 18.2 3.0 3.0
1 1 1
October 1, 1981, through September 30, 1982.
TABLE IIB
Symptom-Free Status at Final-Year Report l: Patients with Successful Percutaneous Transluminal Coronary Angioplasty l-Year Cohort (PTCA between lo/80 and 9181) (n = 906)
Alive and symptom-free No repeat PTCA, CABG or MI Repeat PTCA. no CABG or Ml * October 1, 1981, through September 30, 1982.
2-Year Cohort (PTCA between lo/79 and 9/80) (n = 349)
3-Year Cohort (PTCA between lo/78 and 9/79) (n = 108)
4-Year Cohort (PTCA before 10/78) (n = 34)
n
%
n
%
n
%
n
%
463 62
52.3 7.0
159 28
47.5 8.4
54 10
54.0 10.0
22 0
66.7 0.0
June
spectively, who remained symptom-free were constant. Figure 1 shows the l-year cohorts and the subset of those patients who were symptom-free at 1 year. Repeat PTCA: Of the 1,397 patients who had a successful procedure, 199 (14%) had a repeat PTCA during the first year after the procedure. In most patients, this repeat procedure involved the same lesion initially dilated, although in some patients, other lesions, were attempted during the second procedures. Few repeat procedures were performed after the first, year (Fig. 2). CABG during follow-up: During the first year after an initially successful PTCA, 12% of patients underwent CABG. Failure of an initially successful PTCA and the need for CABG were probably due to restenosis in some patients, and repeat PTCA was not attempted. Undoubtedly, CABG was recommended because of restenosis after a second PTCA in some patients. The reasons for CABG are not available, but CABG was not primarily confined to the first year after initial PTCA, as was repeat PTCA. The proportion of patients with multivessel disease who had CABG within 1 year after PTCA was 16.4% and
15, 1984
THE AMERICAN JOURNAL OF CARDIOLOGY Volume 53
29c
within 2 years after PTCA, 21.4% (Fig. 3). For l-vessel disease, the cumulative rates of CABG were 10.4% at 1 year and 12.1% at 2 years. Myocardial infarction: After hospital discharge 2.79% of patients with an initially successful PTCA sustained clinically apparent, MI during the first year aft.er PTCA. No attempt was made t,o assess the severity of the infarction, that is, transmural vs nontransmural, or the cause, that is, restenosis, occlusion of a vessel in which angioplasty was not performed, and so forth. However, hospitalization was documented in all cases. The frequency of MI in the first year after PTCA was similar in patients with l-vessel and multivessel disease (Table III); in subsequent years, patients with multivessel disease had a greater incidence of MI. Nonfatal MI occurred less frequently in patients who had successful PTCA (Fig. 4). Mortality: A Death Review Committee reviewed available information on the circumstances surrounding the deaths. Sufficient information was available to be certain that 8 patients died from noncardiac causes, and those patients are excluded from this analysis. Therefore, 36 patients died from cardiac causes. Forty-four of 2,272 patients died after discharge from the hospital. In 20 patients who died from cardiac or unknown causes during the follow-up period, the initial PTCA was successful. In the remaining 16 patients who died from cardiac causes, the initial PTCA was unsuccessful.
FIGURE 1. One-year follow-up of 1,379 patients who had initially successful PTCA. Seventy-two percent of these patients were symptom-free, 14% had repeat PTCA and 12% had CABG. The other 2 % had an MI or died. Stippled areas indicated proportion of patients who have no symptoms.
0
I
I
I
1
2
3
YEARS FIGURE 3. Number of patients whose condition was stable 1 to 3 years after an initially successful PTCA procedure without CABG. All pts = all 1,397 patients; MVD = multivessel disease; SVD = single-vessel disease.
TABLE III
Myocardial Infarction During Follow-Up Period by Vessel Disease in Patients with Initially Successful Percutaneous Transluminal Coronary Angioplasty l-Vessel Disease (n = 1,115)
I 0
I 2
1
I
3
YEARS FIGURE 2. Number of patients whose condition was stable without repeat PTCA 1 to 3 years after an initially successful procedure.
Time (yr) Since PTCA
Multivessel Disease (n = 282)
cum n
cum %
cum n
cum %
1
30
2.75
11
2.94
:
37 39
3.47 4.53
14 16
5.91 7.98
cum = cumulative.
3oc
LONG-TERM EFFICACY OF PTCA
Data were examined for predictors of late cardiac death in the hospital as well as in the follow-up period. The most important predictor of late mortality was left main CAD (p
or a subsequent hospitalization (Fig. 6). However, mortality was greater when PTCA was unsuccessful and no subsequent surgery was performed. Discussion The NHLBI PTCA Registry has provided informaction on the initial risks and benefits to the patient. Fortunately, a large subset of patients undergoing initial PTCA had been followed up carefully, and 97% of consecutive patients who had PTCA at 1 of 65 centers from 1977 to 1980 were contacted on the first through fourth anniversary of their initial procedure. This data base of 2,272 patients provides valuable information on the 100
l
=-----Q
(1.1)
(3.2)
. SVD o MVD A LM
80
0 Successful (1397) l All Patients (2272)
;I
I 1
2
YEARS FIGURE 5. Late cardiac deaths in patients after PTCA. LM = left main CAD; other abbreviations as in Figure 3.
1
I
1
I 2
YEARS FIGURE 4. Nonfatal MI in all patients after PTCA attempts and when PTCA was successful.
s
$0 TABLE
IV
Predictors of Mortality in Patients Undergoing Percutaneous Transluminal Coronary Angioplasty
Late cardiac deaths Left main disease (p
5 %
Successful Unsuccessful -Surgery A Unsuccessful-No Surgery 0
l
i______lL__..i
2
YEARS
FIGURE 6. Late cardiac deaths in patients in whom PTCA was successful and those in whom it was not but in whom CABG was performed. The mortality rate in these groups was similar. In patients who had unsuccessful PTCA but had no CABG, the mortality rate was higher.
June15.
long-term effects of this procedure. Almost threefourths of the patients who had an initially successful procedure needed no further procedure during an average of 1.5 years of follow-up. Approximately half the patients remained in stable condition and symptom-free after the initial PTCA. This was the case in each cohort. Thus, on cross-sectional examination, about half the patients were event-free and symptom-free whether the PTCA had been performed 1,2,3 or 4 years previously. Because almost three-fourths the patients were classified as having severe or unstable angina before PTCA, the procedure itself was effective in ameliorating symptoms and signs of myocardial ischemia in approximately half these symptomatic patients. Almost all of the repeat PTCAs were performed in the first year after the initial procedure (Fig. 2). CABG was performed in 12% of the patients during the first year. The cumulative percentage increased to 14,16 and 18% in the second through fourth years after the initial PTCA. The reason these patients underwent CABG is unclear because in most centers restenosis is routinely treated by a second PTCA and not a CABG.
1984
THE AMERICAN JOURNAL OF CARDOLOGY
Volume 53
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Repeat PTCA may have been unavailable or not an alternative for other reasons. Furthermore, CABG was usually recommended in patients in whom restenosis developed after the second PTCA. Again, the requirement for CABG is not limited to the first year after PTCA, but continues at a slow rate in subsequent years. Patients with multivessel disease required subsequent operation more frequently than did patients with Ivessel disease. The mortality rate of patients undergoing PTCA after discharge from the hospital is small. Because most patients had l-vessel disease, they were considered a very low risk population. This proved to be the case, and the mortality in the first through fourth years after PTCA was approximately 1% per year in patients with l-vessel disease. Important predictors of late death were multivessel and left main CAD, either of which predicted a relatively high risk group during the years subsequent to a PTCA attempt. Another relatively high risk group were patients who had unsuccessful PTCA and were subsequently managed with CABG.