- Email: [email protected]
Comparison of direct fick and thermodilution cardiac output techniques at high flow rates
364
BRIEF REPORTS
FIGURE 3. Nuclear magnetic resonance imaging. Direct coronal sectlon from anterlor (A) to posterlor (6). A shows 3 large hepatlc hydatlc cysts (wbffe arrows). Note the displacement of the Inferior vena cava (white arrowhead); a pelvic cyst Is also apparent (black arrowhead). The cardiac hydatld cyst (black arrow) Is nbt well vlsuallzed. B shows 2 hepatlc cysts (whlfe arrows) and a retroperltoneal cyst (whlfe arrowhead) In the psoas muscle.
myocardial and pericardial masses and several cases of hydatid cysts of the heartS5e6The disadvantages of the technique are the irradiation and the need to inject contrast material to outline structural features of the heart. Furthermore, CT can only produce images in 1 anatomic plane, limiting the morphologic analysis and resulting in failure to detect small lesions.5 There is no previous report on the use of NMR to diagnose hydatid cysts. This examination, which is noninvasive as in 2-D echocardiography, can produce images in slices comparable to CT, but in more than 1 anatomic plane and without the necessity of injecting contrast material as in CT. It can give very good images of normal and pathologic cardiac structures provided that electrocardiographic gating is used.6 The imaging period remains slow relative to that of 2-D echocardiography.6 In the present case, the nongated NMR did not allow us to obtain very satisfactory images of the cardiac lesion. Both this technique and CT, as in abdominal sonography, are very effective at evaluating hepatic, renal and pelvic cystic disease, and are also good at diagnosing large retroperitoneal cysts. Nevertheless, CT and NMR are slightly better at demonstrat-
Comparisonof Direct Fick and ThermodilutionCardiacOutput Techniquesat High FlowRates SPENCER H. KUBO, MD J.E.B. BURCHENAL, AB ROBERT J. CODY, MD
From The Division of Cardiology, Department of Medicine, The New York Hospital-Cornell Medical Center, New York, New York 10021. This study was supported in part by General Clinical Research Grant RR-047 from the National Institutes of Health, Bet$esda, Maryland, and a grant from the G. Harold and Leila Y. Mathers Charitable Foundation in memory of Ralph C. Menapace. Manuscript received March 15, 1986; revised manuscript received June 24,1986. accepted July 14,1986.
ing extent of disease, particularly with small retroperitoneal cysts such as the subject of our report. NMR is still the more advantageous of the 2 for examination of the heart because with images in multiple planes it gives a more complete picture. NMR would seem preferable to CT in examining patients with disseminated echinococcosis, if it were as widely available as CT is. It appears that 2-D echocardiography remains the technique of choice for the localization of hydatic cysts of the heart. 1. Perez Gomez F, Damn H, Tamames S. Perrote ]L. Blanes A. Cardiac echinococcosis: clinical picture and complications. Br Heart 1 1973;35:13261331. 2. Oliver JM, Benito LP, Ferrufino 0, Sotillo JF, Nunez L. Cardiac hydatid cyst diagnosed by two-dimensional echocordiography. Am Heart r 1982;104:164165. 3. Kostucki W, Van Kuich M, Cornil A. Changing echocardiogra’phic features of a hydatid cyst of the heart. Br Heart r 1985;54:224-225. 4. Malouf J, Saksouk FA. Alam S, Rizk GK, Dagher I. Hydotid cyst of the heart: diagnosis by two-dimensional echocardiography and computed tomography. Am J Heart J 1985;109:605-607. 5. Gross BH, Glazer GM, Francis IR. Computed tomography of intracardiac and intrapericardial masses. A/R 1983:140:903-907. 6. Higgins CB, Lanzer P, Stark D. Botvinick E, Schiller NB, Lipton MJ, Crooks LE. Kaufman L. Assessment of cardiac anatomy using nuclear resonance imaging. IACC 1985;5;77%885.
S
everal studies have demonstrated an excellent correlation between the thermodilution and direct Fick methods of determining cardiac output (CO)A4 There is generally close agreement between these 2 methods in both animal experiments and patients with a variety of cardiovascular disorders, for a range of CO from 2 to 13 liters/min. However, there are few data assessing the accuracy of the thermodilution technique in patients without left ventricular dysfunction, where exercise CO could approach the theoretical maximum of 25 to 30 liters/min. Therefore, the present study compared these 2 CO techniques at rest and during exercise in patients with congestive heart failure (CHF) representing the low end of the spectrum, and in patients with systemic hypertension in whom cardiac reserve was near normal. The study consisted of 13 patients with CHF (9 men, 4 women, aged 33 to 74 years, mean 54) and 12
February
patients with systemic hypertension (9 men, 3 women, aged 27 to 76 years, mean 50). CHF was due to an ischemic or idiopathic dilated cardiomyopathy. Patients with primary valvular heart disease, recent myocardial infarction or angina pectoris were excluded. Vasodilators were discontinued at least 3 days before the study. A11 hypertensive patients had essential hypertension for at least 2 years, without clinical evidence of CHF. All previous antihypertensive therapy was discontinued at least 1 week before study. The exercise hemodynamic study was identical for both CHF and hypertensive patients as previously described.5 After an overnight fast, a thermodilution catheter was passed percutaneously from an arm or neck vein and a cannula was placed in the brachial artery. After a l-hour equilibration period, the patients were moved to the seated position and measurements at rest were obtained. Bicycle ergometric exercise was begun at a workload of 25 W and increased by 25-W increments every 3 minutes. Exercise was continued until fatigue, providing that the respiratory quotient was greater than 6.95, indicating the onset of anerobic metabolism and maximal exertion. Thermodilution CO was measured with a 9520A Edwards Laboratories computer and injection of 10 ml of ice-cold dextrose through the proximal port. The average of 3 measurements was taken, providing that there was less than 10% variance. If there was more than 20% variance, 2 additional measurements were made, and the high and low values were rejected. CO was determined at rest and during the second minute of each exercise stage. Oxygen consumption (mJ/min) was obtained using a Sensormedics metabolic cart and a tightly fitting face mask. Expired gases were measured continuously and averaged over a ti-minute period for values at rest. The average of the last 2 minutes of the final exercise stage was used for the exercise CO because this period corresponded with the time of the thermodilution CO. Arterial and mixed venous (pulmonary artery) blood specimens were obtained at rest and during the final minute of the last exercise stage and oxygen saturation determined by transmission spectrophotometry. Direct Fick CO was calculated from the equation: oxygen consumption (mVmin)/Z.34 X Hgb (g/dl) X 10 X (arterial - venous 02 saturation). Overall, there was a highly significant correlation between the thermodilution and direct Fick CO methods (Fig. 1) (r = 0.955; p <.OOl). There was close agreement in CHF patients at rest and during exercise for a range of CO between 2.0 and 14 liters/min. There was also a close agreement between the 2 methods in patients with hypertension at rest. However, during exercise, Fick CO was generally higher than thermodilution CO to the extent that several points fell off the line of identity when CO was between 15 and 23 liters/min. Several studies demonstrated an excellent correlation between thermodilution and direct Fick CO methods, but the range of CO has been limited to 2 to 13 liters/min. The present study provides additional in-
1. 1987
THE AMERICAN
JOURNAL
OF CARDIOLOGY
Volume
335
59
24r 2220-
n=50 r =0.955
p < 0.001
18-
0
2
4
6 Direct
8
IO FICK
CHF
o
l
HTN
a
A
12
14
16
CO
( L/min)
18
20
22
24
FIGURE 1. Overall correlation between thermodllutlon and direct Flck methods of cardiac output (CO) determlnatlon for patlentr wlth congestive heart failure (CHF) and hypertension (HTN) at rest and durlng exercise. So//d he Is the line of Identlty. Despite a highly slgnlflcant overall correlation, Flck CO was generally higher than thermodllutlon CO when CO was between 15 and 23 Ilters/mln to the extent that several polnts fell off the line of ldentlty.
formation on the concordance of these techniques when CO approaches the theoretical upper limit. Despite the close overall correlation, there may be an error when CO is greater than 15 liters/min. The absence of identity at high flow rates may represent an underestimation of true CO by the thermodilution technique. Possible errors include nonlinear temperature decay, increased heat exchange at high flow rates,*r6 fluctuation in pulmonary artery temperature during respiration (“physiologic noise”) with hyperventilation,” and less likely inadequate mixing of injectate or poor thermistor frequency response.*s6 These errors can contribute to a falsely decreased CO. Although the direct Fick method of CO determination is well established, there are potential errors with this technique. These include error in estimation of blood oxygen saturation, the presence of anemia in subsets of hypertensive patients, and a small (10 to 15%) but detectable increase of hemoglobin with progressive exercise. Furthermore, at maximal exercise, mixed venous oxygen saturation can decrease below 4070, where greater error may be observed with transmission spectrophotometry. Our hypertensive patients did not have a reduction of mixed venous oxygen saturation below 40% during maximal exercise. These errors could contribute to a falsely increased direct Fick CO. In summary, this study suggests that the thermodilution and direct Fick methods are interchangeable when CO is less than 15 liters/min. However, in situations when CO is greater than 15 liters/min, there may be a systematic error involving 1 or both techniques, requiring further clarification of method.
388
BRIEF REPORTS
Acknowledgment: The suggestions and criticisms of Stanley A. Rubin, MD, are greatly appreciated. 1. Lipkin DP. Poole-Wilson PA. Measurement of cardiac output during exercise by the thermodilution and direct Fick techniques in patients with chronic congestive heart failure. Am J Cardiol 1985:56:321-324. 2. Hillis LD, Firth BG, Winnerford MD. Analysis of factors affecting the variability of Fick versus indicator dilation measurements of cardiac output. Am J Cardiol 1985;56:764-768. 3. Rabin SA. Siemienczuk D, Nathan MD, Prause J. Swan HJC. Accuracy of
laser Recanalizationin Severe End-StagePeripheral VascularDisease GARRETT LEE, MD ROBERT L. REIS, MD MICHAEL D. BOGGAN, MD MING C. CHAN, MD MARSHALL H. LEE, MD REGINALD I. LOW, MD HAMNER HANNAH, Ill, MD DEAN T. MASON, MD
A
pplication of lasers to vaporize coronary atherosclerotic obstruction was initially described in 1981.l Since then, the technique has been applied clinically to coronary arteries on an experimental’basis.2 This report objectively describes successful long-term laser recanalization using a catheter containing a laser-heated metal cap3 in a patient with severe end-stage peripheral vascular disease. From the Northern California Heart & Lung Institute, Concord, California; Cedars Medical Center, Miami, Florida; and The Western Heart Institute, St. Mary’s Hospital and Medical Center, San Francisco, California. Manuscript received and accepted August 15.1986.
cardiac output, oxygen uptake. and arteriovenous oxygen difference at rest, during exercise and after vosodilator therapy in patients with severe, chronic heart failure. Am [ Cardiol 1982;50:973-978. 4. White SW, McRitchie RJ, Porges WL. A comparison between thermodilution, electromagnetic and Doppler methods for cardiac output measurement in the rabbit. Clin Exp Pharmacol Physiol 1974;1:79-92. 6. Cody RJ, Kubo SH, Covit AB. Miiller FB, Lopez-Ovejero J, Laragh JH. Exercise hemodynamics and oxygen delivery in human hypertension: response to verapamil. Hypertension 1986;8:3-10. 6. Korner PI, Hilder RG. Measurement of cardiac output and regional blood flow by thermodilution. Clin Exp Pharmacol Physiol 1974:suppI 1:47-66.
A 56-year-old insulin-dependent diabetic woman with severe right leg claudication was having ischemic leg pain at rest that required narcotic agents for relief, and she was referred for right-leg amputation. The right femoral pulse was palpable but distal pulses were absent. She had a pregangrenous right foot and a nonhealing ulcer at the right lateral malleolus. An aortogram showed complete obstruction of the right hypogastric, common femoral, superficial femoral, profunda femoris and popliteal arteries (Fig. 1). There was reconstitution through collateral vessels of the profunda at the level of the inferior ramus of the pubis. In lieu of leg amputation, she agreed, after informed consent, to participate in an approved FDA and institutional review board laser revascularization protocol. To provide adequate blood inflow to the right lower extremity, a Gore-Tee graft was constructed from the common iliac artery to the surgically endarterectomized right common femoral artery. Distal to this latter site, lumenoplasty of the right profunda femoris and several collateral arteries of the common femoral was performed using a catheter containing a 400-p core quartz fiber attached to a short metal cap at its distal end. A total of 137 1 was applied from an argon laser (Cooper Lasersonics model 770). In addition, detached intima in the right common femoral artery was welded using the laser device. At 2 weeks and at 5 months after the procedure, digital subtraction angiography was done to evaluate the treated areas. The iliofemoral graft was patent; beyond the
FIGURE 1. Len, preoperative aortic arterlogram shows abrupt occlusion of the distal right common femoral artery (/arge arrow). Righf, 5 months after operation, digital subtraction angiography shows the widely patent graft (g) hooded onto the right common femoral artery as an onlay patch arterioplasty. The laser-effected recanalization of the profunda femorls artery (p) was now visualized, as well as was the patency of the laser-treated collateral vessels. C = circumflex iliac artery.
BRIEF REPORTS
FIGURE 3. Nuclear magnetic resonance imaging. Direct coronal sectlon from anterlor (A) to posterlor (6). A shows 3 large hepatlc hydatlc cysts (wbffe arrows). Note the displacement of the Inferior vena cava (white arrowhead); a pelvic cyst Is also apparent (black arrowhead). The cardiac hydatld cyst (black arrow) Is nbt well vlsuallzed. B shows 2 hepatlc cysts (whlfe arrows) and a retroperltoneal cyst (whlfe arrowhead) In the psoas muscle.
myocardial and pericardial masses and several cases of hydatid cysts of the heartS5e6The disadvantages of the technique are the irradiation and the need to inject contrast material to outline structural features of the heart. Furthermore, CT can only produce images in 1 anatomic plane, limiting the morphologic analysis and resulting in failure to detect small lesions.5 There is no previous report on the use of NMR to diagnose hydatid cysts. This examination, which is noninvasive as in 2-D echocardiography, can produce images in slices comparable to CT, but in more than 1 anatomic plane and without the necessity of injecting contrast material as in CT. It can give very good images of normal and pathologic cardiac structures provided that electrocardiographic gating is used.6 The imaging period remains slow relative to that of 2-D echocardiography.6 In the present case, the nongated NMR did not allow us to obtain very satisfactory images of the cardiac lesion. Both this technique and CT, as in abdominal sonography, are very effective at evaluating hepatic, renal and pelvic cystic disease, and are also good at diagnosing large retroperitoneal cysts. Nevertheless, CT and NMR are slightly better at demonstrat-
Comparisonof Direct Fick and ThermodilutionCardiacOutput Techniquesat High FlowRates SPENCER H. KUBO, MD J.E.B. BURCHENAL, AB ROBERT J. CODY, MD
From The Division of Cardiology, Department of Medicine, The New York Hospital-Cornell Medical Center, New York, New York 10021. This study was supported in part by General Clinical Research Grant RR-047 from the National Institutes of Health, Bet$esda, Maryland, and a grant from the G. Harold and Leila Y. Mathers Charitable Foundation in memory of Ralph C. Menapace. Manuscript received March 15, 1986; revised manuscript received June 24,1986. accepted July 14,1986.
ing extent of disease, particularly with small retroperitoneal cysts such as the subject of our report. NMR is still the more advantageous of the 2 for examination of the heart because with images in multiple planes it gives a more complete picture. NMR would seem preferable to CT in examining patients with disseminated echinococcosis, if it were as widely available as CT is. It appears that 2-D echocardiography remains the technique of choice for the localization of hydatic cysts of the heart. 1. Perez Gomez F, Damn H, Tamames S. Perrote ]L. Blanes A. Cardiac echinococcosis: clinical picture and complications. Br Heart 1 1973;35:13261331. 2. Oliver JM, Benito LP, Ferrufino 0, Sotillo JF, Nunez L. Cardiac hydatid cyst diagnosed by two-dimensional echocordiography. Am Heart r 1982;104:164165. 3. Kostucki W, Van Kuich M, Cornil A. Changing echocardiogra’phic features of a hydatid cyst of the heart. Br Heart r 1985;54:224-225. 4. Malouf J, Saksouk FA. Alam S, Rizk GK, Dagher I. Hydotid cyst of the heart: diagnosis by two-dimensional echocardiography and computed tomography. Am J Heart J 1985;109:605-607. 5. Gross BH, Glazer GM, Francis IR. Computed tomography of intracardiac and intrapericardial masses. A/R 1983:140:903-907. 6. Higgins CB, Lanzer P, Stark D. Botvinick E, Schiller NB, Lipton MJ, Crooks LE. Kaufman L. Assessment of cardiac anatomy using nuclear resonance imaging. IACC 1985;5;77%885.
S
everal studies have demonstrated an excellent correlation between the thermodilution and direct Fick methods of determining cardiac output (CO)A4 There is generally close agreement between these 2 methods in both animal experiments and patients with a variety of cardiovascular disorders, for a range of CO from 2 to 13 liters/min. However, there are few data assessing the accuracy of the thermodilution technique in patients without left ventricular dysfunction, where exercise CO could approach the theoretical maximum of 25 to 30 liters/min. Therefore, the present study compared these 2 CO techniques at rest and during exercise in patients with congestive heart failure (CHF) representing the low end of the spectrum, and in patients with systemic hypertension in whom cardiac reserve was near normal. The study consisted of 13 patients with CHF (9 men, 4 women, aged 33 to 74 years, mean 54) and 12
February
patients with systemic hypertension (9 men, 3 women, aged 27 to 76 years, mean 50). CHF was due to an ischemic or idiopathic dilated cardiomyopathy. Patients with primary valvular heart disease, recent myocardial infarction or angina pectoris were excluded. Vasodilators were discontinued at least 3 days before the study. A11 hypertensive patients had essential hypertension for at least 2 years, without clinical evidence of CHF. All previous antihypertensive therapy was discontinued at least 1 week before study. The exercise hemodynamic study was identical for both CHF and hypertensive patients as previously described.5 After an overnight fast, a thermodilution catheter was passed percutaneously from an arm or neck vein and a cannula was placed in the brachial artery. After a l-hour equilibration period, the patients were moved to the seated position and measurements at rest were obtained. Bicycle ergometric exercise was begun at a workload of 25 W and increased by 25-W increments every 3 minutes. Exercise was continued until fatigue, providing that the respiratory quotient was greater than 6.95, indicating the onset of anerobic metabolism and maximal exertion. Thermodilution CO was measured with a 9520A Edwards Laboratories computer and injection of 10 ml of ice-cold dextrose through the proximal port. The average of 3 measurements was taken, providing that there was less than 10% variance. If there was more than 20% variance, 2 additional measurements were made, and the high and low values were rejected. CO was determined at rest and during the second minute of each exercise stage. Oxygen consumption (mJ/min) was obtained using a Sensormedics metabolic cart and a tightly fitting face mask. Expired gases were measured continuously and averaged over a ti-minute period for values at rest. The average of the last 2 minutes of the final exercise stage was used for the exercise CO because this period corresponded with the time of the thermodilution CO. Arterial and mixed venous (pulmonary artery) blood specimens were obtained at rest and during the final minute of the last exercise stage and oxygen saturation determined by transmission spectrophotometry. Direct Fick CO was calculated from the equation: oxygen consumption (mVmin)/Z.34 X Hgb (g/dl) X 10 X (arterial - venous 02 saturation). Overall, there was a highly significant correlation between the thermodilution and direct Fick CO methods (Fig. 1) (r = 0.955; p <.OOl). There was close agreement in CHF patients at rest and during exercise for a range of CO between 2.0 and 14 liters/min. There was also a close agreement between the 2 methods in patients with hypertension at rest. However, during exercise, Fick CO was generally higher than thermodilution CO to the extent that several points fell off the line of identity when CO was between 15 and 23 liters/min. Several studies demonstrated an excellent correlation between thermodilution and direct Fick CO methods, but the range of CO has been limited to 2 to 13 liters/min. The present study provides additional in-
1. 1987
THE AMERICAN
JOURNAL
OF CARDIOLOGY
Volume
335
59
24r 2220-
n=50 r =0.955
p < 0.001
18-
0
2
4
6 Direct
8
IO FICK
CHF
o
l
HTN
a
A
12
14
16
CO
( L/min)
18
20
22
24
FIGURE 1. Overall correlation between thermodllutlon and direct Flck methods of cardiac output (CO) determlnatlon for patlentr wlth congestive heart failure (CHF) and hypertension (HTN) at rest and durlng exercise. So//d he Is the line of Identlty. Despite a highly slgnlflcant overall correlation, Flck CO was generally higher than thermodllutlon CO when CO was between 15 and 23 Ilters/mln to the extent that several polnts fell off the line of ldentlty.
formation on the concordance of these techniques when CO approaches the theoretical upper limit. Despite the close overall correlation, there may be an error when CO is greater than 15 liters/min. The absence of identity at high flow rates may represent an underestimation of true CO by the thermodilution technique. Possible errors include nonlinear temperature decay, increased heat exchange at high flow rates,*r6 fluctuation in pulmonary artery temperature during respiration (“physiologic noise”) with hyperventilation,” and less likely inadequate mixing of injectate or poor thermistor frequency response.*s6 These errors can contribute to a falsely decreased CO. Although the direct Fick method of CO determination is well established, there are potential errors with this technique. These include error in estimation of blood oxygen saturation, the presence of anemia in subsets of hypertensive patients, and a small (10 to 15%) but detectable increase of hemoglobin with progressive exercise. Furthermore, at maximal exercise, mixed venous oxygen saturation can decrease below 4070, where greater error may be observed with transmission spectrophotometry. Our hypertensive patients did not have a reduction of mixed venous oxygen saturation below 40% during maximal exercise. These errors could contribute to a falsely increased direct Fick CO. In summary, this study suggests that the thermodilution and direct Fick methods are interchangeable when CO is less than 15 liters/min. However, in situations when CO is greater than 15 liters/min, there may be a systematic error involving 1 or both techniques, requiring further clarification of method.
388
BRIEF REPORTS
Acknowledgment: The suggestions and criticisms of Stanley A. Rubin, MD, are greatly appreciated. 1. Lipkin DP. Poole-Wilson PA. Measurement of cardiac output during exercise by the thermodilution and direct Fick techniques in patients with chronic congestive heart failure. Am J Cardiol 1985:56:321-324. 2. Hillis LD, Firth BG, Winnerford MD. Analysis of factors affecting the variability of Fick versus indicator dilation measurements of cardiac output. Am J Cardiol 1985;56:764-768. 3. Rabin SA. Siemienczuk D, Nathan MD, Prause J. Swan HJC. Accuracy of
laser Recanalizationin Severe End-StagePeripheral VascularDisease GARRETT LEE, MD ROBERT L. REIS, MD MICHAEL D. BOGGAN, MD MING C. CHAN, MD MARSHALL H. LEE, MD REGINALD I. LOW, MD HAMNER HANNAH, Ill, MD DEAN T. MASON, MD
A
pplication of lasers to vaporize coronary atherosclerotic obstruction was initially described in 1981.l Since then, the technique has been applied clinically to coronary arteries on an experimental’basis.2 This report objectively describes successful long-term laser recanalization using a catheter containing a laser-heated metal cap3 in a patient with severe end-stage peripheral vascular disease. From the Northern California Heart & Lung Institute, Concord, California; Cedars Medical Center, Miami, Florida; and The Western Heart Institute, St. Mary’s Hospital and Medical Center, San Francisco, California. Manuscript received and accepted August 15.1986.
cardiac output, oxygen uptake. and arteriovenous oxygen difference at rest, during exercise and after vosodilator therapy in patients with severe, chronic heart failure. Am [ Cardiol 1982;50:973-978. 4. White SW, McRitchie RJ, Porges WL. A comparison between thermodilution, electromagnetic and Doppler methods for cardiac output measurement in the rabbit. Clin Exp Pharmacol Physiol 1974;1:79-92. 6. Cody RJ, Kubo SH, Covit AB. Miiller FB, Lopez-Ovejero J, Laragh JH. Exercise hemodynamics and oxygen delivery in human hypertension: response to verapamil. Hypertension 1986;8:3-10. 6. Korner PI, Hilder RG. Measurement of cardiac output and regional blood flow by thermodilution. Clin Exp Pharmacol Physiol 1974:suppI 1:47-66.
A 56-year-old insulin-dependent diabetic woman with severe right leg claudication was having ischemic leg pain at rest that required narcotic agents for relief, and she was referred for right-leg amputation. The right femoral pulse was palpable but distal pulses were absent. She had a pregangrenous right foot and a nonhealing ulcer at the right lateral malleolus. An aortogram showed complete obstruction of the right hypogastric, common femoral, superficial femoral, profunda femoris and popliteal arteries (Fig. 1). There was reconstitution through collateral vessels of the profunda at the level of the inferior ramus of the pubis. In lieu of leg amputation, she agreed, after informed consent, to participate in an approved FDA and institutional review board laser revascularization protocol. To provide adequate blood inflow to the right lower extremity, a Gore-Tee graft was constructed from the common iliac artery to the surgically endarterectomized right common femoral artery. Distal to this latter site, lumenoplasty of the right profunda femoris and several collateral arteries of the common femoral was performed using a catheter containing a 400-p core quartz fiber attached to a short metal cap at its distal end. A total of 137 1 was applied from an argon laser (Cooper Lasersonics model 770). In addition, detached intima in the right common femoral artery was welded using the laser device. At 2 weeks and at 5 months after the procedure, digital subtraction angiography was done to evaluate the treated areas. The iliofemoral graft was patent; beyond the
FIGURE 1. Len, preoperative aortic arterlogram shows abrupt occlusion of the distal right common femoral artery (/arge arrow). Righf, 5 months after operation, digital subtraction angiography shows the widely patent graft (g) hooded onto the right common femoral artery as an onlay patch arterioplasty. The laser-effected recanalization of the profunda femorls artery (p) was now visualized, as well as was the patency of the laser-treated collateral vessels. C = circumflex iliac artery.