Percutaneous Transluminal Angioplasty for Transylant Renal Artery Stenosis Terence A. 5. Matalon, M D Michael J. Thompson, M D Suresh K. Patel, M D Michael C. Brunner, M D Frederick K. Merkel, M D Stephen C. Jensik, MD, PhD Indexterms: Kidney, transplantation, 81.455 arteries, stenOsisOr Obstruction, 81.4557 Renal arteries, translurninal angioplasty, 961.454
JVIR 1992; 3:55-58 Abbreviations: BUN = blood urea nitrogen, DSA = digital subtraction angiography, PTA = percutaneous transluminal angioplasty, TRAS = transplant renal artery stenosis
A recent report has challenged the efficacy and safety of percutaneous transluminal angioplasty (PTA)for the treatment of transplant renal artery stenosis (TRAS).From January 1983to December 1990, 24 PTA procedures were performed for TRAS in 18 patients. The stenoses were anastomotic in two cases, in the main renal artery in 14, and segmental in eight. After PTA, the residual stenosis was less than 20%in 14 (58%),20%-50%in four (17%),and greater than 50% in six (25%).The mean diastolic blood pressure decreased from 106 mm Hg 1day prior to PTA to 82 mm Hg 1day after PTA. Long-term follow-upmean diastolic blood pressure (at 2-32 months) was 93 mm Hg (P < .01). Eleven of the 18 patients (63%)had a 10%or greater reduction in diastolic blood pressure on long-term follow-up. Major complications occurred in two patients; one groin hematoma required surgical evacuation, and one polar infarct led to hypertension that was difficult to control. No surgical revisions of the transplant renal artery were necessary. The authors' data indicate that PTA should remain the treatment of choice for nonanastomotic TRAS.
renal artery stenosis (TRAS) is an uncommon but serious complication of renal transplantation. I t has been reported in up to 25% of renal transplants (1); however, large series report a prevalence of 1.5%-7% (2,3). The majority of patients have poorly controlled or uncontrolled hypertension, with or without worsening renal function, at presentation. Management options include medical control of hypertension, surgical correction of the arterial lesion, or percutaneous translumind angioplasty (PTA). PTA has become the treatment of choice for TRAS (3,4). A recent report challenges the safety and efficacy of this procedure and concludes that surgical correction is the treatment of choice (2). The data from 24 PTA procedures in 18 patients was reviewed to evaluate the role of PTA in the treatment of TRAS. TRANSPLANT
' From the Departments of Diagnostic Radiology and Nuclear Medicine (T.A.S.M., M.J.T., S.K.P., M.C.B.) and Surgery (F.K.M., S.C.J.), Rush-presbyterian-St Luke's Medical Center, 1653 W. Congress Pkwy, Chicago, IL 60612. From the 1991 SCVIR annual meeting. Received May 16, 1991; revision requested J U ~ Y5; revision received September 4; accepted September 9. Address reprint requests to T.A.S.M. SCVIR, 1992
PATIENTS AND METHODS In a retrospective review, 18 patients with TRAS underwent 24 PTA procedures between January 1983 and December 1990. Two patients had two separate lesions, two developed restenosis, and two technical failures occurred. All stenotic lesions were identified with digital subtraction angiography (DSA). The patient group included 17 men and one woman; mean age was 43.4 years (range, 22-68 years). Transplants were single adult cadaveric in 11, double pediatric cadaveric in five, and living related donor in two. All anastomoses were end-to-side with the external iliac artery except for one end-to-end anastomosis with the internal iliac artery. The stenoses were anastomotic in two patients, in the main renal artery in 14, and segmental in eight. One
55
56
Journal of Vascular and I[nterventional Radiology
February 1992
patient had a concomitant common iliac lesion with an anastomotic stenosis. Patients presented with poorly controlled or uncontrolled hypertension (n = 131, decreasing renal function (n = 4), and a bruit over the transplant site (n = 1). The mean time between transplantation and PTA was 13.8 months (range, 1-111 months). PTA procedures were performed with use of standard techniaue depending on the stenosis lockion (Fig 1). Since the large majority of the lesions have been treated within the past 2 years, 5-F or smaller systems were used in almost all cases. Lesions were dilated, usually over a hydrophilic guide wire (Terumo, Tokyo). Kissing balloons were used for a branch stenosis in two cases (Fig 2). Balloon size was matched to adjacent vessel size, and dilation was performed at the minimum pressure needed to relieve the stenosis. Multiple inflations were performed when necessary. Patients received preprocedural nifedi~ine.Intraarterial nitroglycerine A d sublingual nifedipine were administered liberally to avoid arterial spasm. Clinical data were collected by means of manual chart search. Data evaluated included the condition at the time of TRAS diagnosis and diastolic blood pressure prior to and following PTA (at 1day, 1week, and long-term follow-up). The number of blood pressure medications prescribed prior to PTA and on hospital discharge were noted. Blood urea nitrogen (BUN) and creatinine values were obtained prior to PTA, on hospital discharge, and at long-term follow-up. Biopsy specimen reports were evaluated for the presence or absence of rejection. Radiology reports and hard-copy images were reviewed to determine the location of the stenosis and technical outcome. Complications were followed up by medical record review. In accordance with the guidelines approved by the Society of Cardiovascular and Interventional Radiology (SCVIR) ( 9 , technical success for PTA is defined as relief of stenosis or
Figure 1. (a)Right external iliac artery DSA image obtained from a patient with a double pediatric renal transplant prior to PTA. There is a high-grade, short-segment, nonanastomotic main renal artery stenosis to the lateral kidney. (b)After PTA, complete resolution of the lateral main renal artery stenosis to the lateral kidney is seen. Blood pressure decreased from 1541112before PTA to 140182 mm Hg thereafter.
occlusion with a residual stenosis of 20% or less. Clinical success is the complete relief or substantial improvement in presenting symptoms.
RESULTS All patients with documented TRAS underwent PTA. Two purely technical failures occurred. In one case we were unable to cross a stenosis with a balloon catheter, and in the other a balloon ruptured. Both lesions were successfully dilated on subsequent attempts. Ten lesions had a greater than 20% residual stenosis, including the two previously mentioned technical failures. Thus, technical success was achieved in 14 of 24 procedures (58%).A further breakdown of technical results reveals less than 20% residual stenosis in 14 (58%),between 20% and 50% residual stenosis in four (17%), and greater than 50% stenosis in six (25%).Restenosis occurred in two patients with main renal artery stenosis 4 months after PTA, and both were successfully treated with repeat PTA.
The average mean diastolic blood pressure was 106 mm Hg (range, 88120 mm Hg) 1day prior to PTA and was 81 mm Hg (range, 70-92 mm Hg) 1day after PTA. Mean blood pressure at 1week was 84 mm Hg (range, 70-92 mm Hg). At follow-up (average, 11.5 months; range, 2-32 months), diastolic blood pressure was 93 mm Hg (range, 70-112 mm Hg). The mean number of blood pressure medications prescribed decreased from 2.4 (range, one to five) prior to PTA to 1.4 (range, zero to three) at hospital discharge. The number of blood pressure medications was decreased in 13 patients and unchanged in five. Fifteen of 18 patients (83%)experienced a 10% or greater reduction in mean blood pressure 1week following PTA. Long-term follow-up (average, 11.5 months; range, 2-32 months) showed 11of 18 (63%)had a persistent 10% or greater decrease in mean blood pressure. Among these 11patients, six also were taking fewer blood pressure medications. Among the seven patients with no long-term change in blood pressure, the number of blood pressure medi-
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a. b. c. Figure 2. (a)Right external iliac DSA image obtained from a patient with a single renal transplant. Stenoses of the main renal artery and its proximal branch are seen. (b) During PTA, kissing balloons were placed across the lesion and in the adjacent branch. ( c ) After PTA, there is complete resolution of the branch stenosis. Blood pressure prior to angioplasty was 1501108 and after angioplasty was 132190 mm Hg.
cations was decreased in six. The BUN level decreased from 44.6 mg/dL (15.9 mmol/L) (range, 14-105 mg/dL L5.0-37.5 mmol/L]) before PTA to 39 mg/dL (13.9 mmol/L) (range, 9-56 mg/dL [3.2-20 mmol/ Ll) after PTA. The creatinine level decreased from 2.6 mg/dL (230 kmol/L) (range, 0.8-5.7 mg/dL [70500 kmol/Ll) to 2.0 mg/dL (180 kmol/L) (range, 0.8-4.0 mg/dL [70350 pmol/LI). At follow-up, BUN and creatinine levels were decreased by 10% or greater in nine patients (50%),were unchanged in seven (39%), and were increased in two (11%). Biopsy in the latter two cases showed acute tubular necrosis in one and chronic rejection in the other. For two of the four patients with decreasing renal function at presentation, BUN and creatinine levels decreased; for the other two, the levels remained unchanged. One patient required surgical evacuation of a groin hematoma and repair of the site of an inadvertent femoral venous puncture following a technically successful common iliac and main renal artery PTA procedure. A second major complication was a 20% polar infarct following suc-
cessful dilation of a main renal artery lesion. Blood pressure control became difficult. In this patient, graft function was lost subsequent to a bizarre allergic reaction following an insect bite 8 months after PTA. Minor complications included three groin hematomas and a small pseudoaneurysm at the puncture site. None became clinically apparent nor required additional intervention. Long-term patient follow-up information from 2 to 72 months (mean, 23.3 months) after PTA is available in all patients. Two patients have died: one of multiple myeloma and one of sepsis unrelated to PTA. Two patients have lost renal function because of chronic rejection and require hemodialysis. Two others underwent repeat transplantation: one for chronic rejection and one after the previous described anaphylactic reaction. The remaining 12 patients retain renal transplant function without dialysis. Transplant biopsies were performed in 13 patients. Twelve showed evidence of rejection, and one showed acute tubular necrosis. Four patients with rejection have died or lost graft function.
DISCUSSION PTA has become a safe and effective therapy for TRAS. Other large series have reported clinical improvement in 63%-76% of patients (3,643). A recent report challenges the efficacy and safety of PTA for TRAS. In that report, clinical improvement was achieved in only 20% of patients, with a very high rate of serious complications (seven of 31, 22.5%) (2). This was not our experience. A complication requiring surgical intervention occurred in only one of 24 procedures. A second complication (polar infarct) significantly changed the patient's course. No surgical revisions of the transplant renal artery were necessary. A major difference between our series and that of Roberts et a1 (2) is the location of the lesion. The majority of lesions in their study were anastomotic (24 of 31, 77%),while only two anastomotic lesions (11%) were present in our series. Others have reported lower success rates with anastomotic lesions (9). Chandrasoma and Aberle reported histologic differences between anastomotic
58
Journal of Vascular and Interventional Radiology
February 1992
lesions and nonanastomotic lesions (10). However, comparable success rates for PTA of anastomotic and nonanastomotic lesions have also been reported (3,6). Anastomotic lesions may be secondary to surgical technique (1,ll ) , while nonanastomotic lesions may have an immunologic origin (12). Our study does not address this issue, as the population is skewed toward nonanastomotic lesions. However, the fact that 12 of 18 patients in our study had biopsy evidence of rejection does favor an immunologic mechanism for nonanastomotic lesions. While our study does not directly compare results of PTA and surgical correction, it does support the use of PTA for nonanastomotic lesions. Surgical success ranges from 7.5% to 75%, with major complications i n 0%-15% (1,2,13-16). Our results are comparable. Our technical success rate was 58%. Clinical success is difficult to define. A complete cure (patient is normotensive without receiving blood pressure medication) is rare and unexpected given the multiple causes of posttransplant hypertension. We consider a 10% reduction in diastolic blood pressure to be a significant improvement. This often reduced diastolic blood pressure from above 100 to below 100 mm Hg. The Hypertension Detection and Follow-up Program Cooperative Group showed a significantly lower longterm morbidity and mortality when the diastolic blood pressure was in the range of 90-104 mm Hg versus above 104 mm Hg (17).Also a reduction of number of blood pressure medications may have a major effect on the patient. These patients are often taking multiple medications, and a decrease in the number of blood pressure medications may help reduce morbidity from drug interactions. We were not as successful in improving renal function in those patients presenting with decreasing renal function. Two of four had a 10% reduction in BUN and creatinine levels. All four patients had biopsy evidence of chronic rejection. This may
contribute to the lower success rates in these patients. Roberts et al reported a major complication rate of 22.5% (graft loss or emergency intervention required). Our major complication rate was much lower; 8.3% (two of 24 procedures), with no periprocedural graft loss and only one emergent non-graft intervention required. It is not known why anastomotic lesions are associated with a higher major complication rate, although the resistant nature of the lesions may necessitate using 7-F stiffer systems with an attendant increase in morbidity. Most of our procedures were performed using 5-F or coronary systems. Our data indicate that PTA should remain the treatment of choice for nonanastomotic TRAS. The procedure is relatively safe, and clinical success rates are comparable to those achieved with surgical correction. References 1. Lacombe M. Arterial stenosis complicating renal transplantation in man: a study of 38 cases. Ann Surg 1975; 181:283-288. 2. Roberts JP, Ascher NL, Fyrd DS, et al. Transplant renal artery stenosis. Transplantation 1989; 48:580583. 3. Greenstein SM, Verstandig A, McLean GK, et al. Percutaneous transluminal angioplasty. Transplantation 1987;43:29-32. 4. Aliabadi H, McLorie GA, Churchill BM, et al. Percutaneous translumind angioplasty for transplant renal stenosis in children. J Urol 1990; 143:569-573. 5. Standards of Practice Committee of the Society of Cardiovascular and Interventional Radiology. Guidelines for percutaneous transluminal angioplasty.JVIR 1990; 1:5-15. 6. Clements R, Evans C, Salaman JR. Percutaneous transluminal angioplasty of renal transplant artery stenosis. Clin Radio1 1987;38:235-237. 7. Mollenkopf F, Matas A, Spragregen S, et al. Percutaneous transluminal angioplasty for transplant renal artery stenosis. Transplant Proc 1983; 15:1089-1091. 8. Raynaud A, Bedrossian J, Remy P, et al. Percutaneous transluminal angioplasty of renal transplant arte-
rial stenosis.AJR 1986; 1469353857. Grossman RA, Dafoe DC, Schoenfeld RB, et al. Percutaneous transluminal angioplasty treatment of renal transplant artery stenosis. Transplantation 1982; 34:339-343. Chandrasoma P, Aberle AM. Anastomotic line renal artery stenosis after transplantation.J Urol 1986; 135:1159-1162. Oakes DD, Spees EK, McAllister HA, et al. Arterial injury during perfusion preservation: a possible cause of post-transplant renal artery stenosis. Surgery 1981; 89:210-213. Sniderman KW, Sprayregen S, Sos TA, et al. Percutaneous transluminal dilation in renal transplant arterial stenosis. Transplantation 1980; 30:440443. Osborn DE, Castro JE, Shackman R. Surgical correction of arterial stenosis in renal allografts. Br J Urol 1976; 48:221-224. Smith RB, Cosmi AB, London R, et al. Diagnosis and management of arterial stenosis causing hypertension after successful renal transplantation. J Urol 1979; 115:639643. Minda R, Alexander JW, Miller S, et al. Renal allograft artery stenosis. Am J Surg 1977; 134:400403. Kauffman HM, Sampson D, Fox PS, et al. Prevention of transplant renal artery stenosis. Surgery 1977; 81:161-163. Hypertension Detection and Follow-up Program Cooperative Group. Five-year findings of hypertension detection and follow-up program. JAMA 1979; 242:2562-2571.
JVIR 1992; 3:55-58 Abbreviations: BUN = blood urea nitrogen, DSA = digital subtraction angiography, PTA = percutaneous transluminal angioplasty, TRAS = transplant renal artery stenosis
A recent report has challenged the efficacy and safety of percutaneous transluminal angioplasty (PTA)for the treatment of transplant renal artery stenosis (TRAS).From January 1983to December 1990, 24 PTA procedures were performed for TRAS in 18 patients. The stenoses were anastomotic in two cases, in the main renal artery in 14, and segmental in eight. After PTA, the residual stenosis was less than 20%in 14 (58%),20%-50%in four (17%),and greater than 50% in six (25%).The mean diastolic blood pressure decreased from 106 mm Hg 1day prior to PTA to 82 mm Hg 1day after PTA. Long-term follow-upmean diastolic blood pressure (at 2-32 months) was 93 mm Hg (P < .01). Eleven of the 18 patients (63%)had a 10%or greater reduction in diastolic blood pressure on long-term follow-up. Major complications occurred in two patients; one groin hematoma required surgical evacuation, and one polar infarct led to hypertension that was difficult to control. No surgical revisions of the transplant renal artery were necessary. The authors' data indicate that PTA should remain the treatment of choice for nonanastomotic TRAS.
renal artery stenosis (TRAS) is an uncommon but serious complication of renal transplantation. I t has been reported in up to 25% of renal transplants (1); however, large series report a prevalence of 1.5%-7% (2,3). The majority of patients have poorly controlled or uncontrolled hypertension, with or without worsening renal function, at presentation. Management options include medical control of hypertension, surgical correction of the arterial lesion, or percutaneous translumind angioplasty (PTA). PTA has become the treatment of choice for TRAS (3,4). A recent report challenges the safety and efficacy of this procedure and concludes that surgical correction is the treatment of choice (2). The data from 24 PTA procedures in 18 patients was reviewed to evaluate the role of PTA in the treatment of TRAS. TRANSPLANT
' From the Departments of Diagnostic Radiology and Nuclear Medicine (T.A.S.M., M.J.T., S.K.P., M.C.B.) and Surgery (F.K.M., S.C.J.), Rush-presbyterian-St Luke's Medical Center, 1653 W. Congress Pkwy, Chicago, IL 60612. From the 1991 SCVIR annual meeting. Received May 16, 1991; revision requested J U ~ Y5; revision received September 4; accepted September 9. Address reprint requests to T.A.S.M. SCVIR, 1992
PATIENTS AND METHODS In a retrospective review, 18 patients with TRAS underwent 24 PTA procedures between January 1983 and December 1990. Two patients had two separate lesions, two developed restenosis, and two technical failures occurred. All stenotic lesions were identified with digital subtraction angiography (DSA). The patient group included 17 men and one woman; mean age was 43.4 years (range, 22-68 years). Transplants were single adult cadaveric in 11, double pediatric cadaveric in five, and living related donor in two. All anastomoses were end-to-side with the external iliac artery except for one end-to-end anastomosis with the internal iliac artery. The stenoses were anastomotic in two patients, in the main renal artery in 14, and segmental in eight. One
55
56
Journal of Vascular and I[nterventional Radiology
February 1992
patient had a concomitant common iliac lesion with an anastomotic stenosis. Patients presented with poorly controlled or uncontrolled hypertension (n = 131, decreasing renal function (n = 4), and a bruit over the transplant site (n = 1). The mean time between transplantation and PTA was 13.8 months (range, 1-111 months). PTA procedures were performed with use of standard techniaue depending on the stenosis lockion (Fig 1). Since the large majority of the lesions have been treated within the past 2 years, 5-F or smaller systems were used in almost all cases. Lesions were dilated, usually over a hydrophilic guide wire (Terumo, Tokyo). Kissing balloons were used for a branch stenosis in two cases (Fig 2). Balloon size was matched to adjacent vessel size, and dilation was performed at the minimum pressure needed to relieve the stenosis. Multiple inflations were performed when necessary. Patients received preprocedural nifedi~ine.Intraarterial nitroglycerine A d sublingual nifedipine were administered liberally to avoid arterial spasm. Clinical data were collected by means of manual chart search. Data evaluated included the condition at the time of TRAS diagnosis and diastolic blood pressure prior to and following PTA (at 1day, 1week, and long-term follow-up). The number of blood pressure medications prescribed prior to PTA and on hospital discharge were noted. Blood urea nitrogen (BUN) and creatinine values were obtained prior to PTA, on hospital discharge, and at long-term follow-up. Biopsy specimen reports were evaluated for the presence or absence of rejection. Radiology reports and hard-copy images were reviewed to determine the location of the stenosis and technical outcome. Complications were followed up by medical record review. In accordance with the guidelines approved by the Society of Cardiovascular and Interventional Radiology (SCVIR) ( 9 , technical success for PTA is defined as relief of stenosis or
Figure 1. (a)Right external iliac artery DSA image obtained from a patient with a double pediatric renal transplant prior to PTA. There is a high-grade, short-segment, nonanastomotic main renal artery stenosis to the lateral kidney. (b)After PTA, complete resolution of the lateral main renal artery stenosis to the lateral kidney is seen. Blood pressure decreased from 1541112before PTA to 140182 mm Hg thereafter.
occlusion with a residual stenosis of 20% or less. Clinical success is the complete relief or substantial improvement in presenting symptoms.
RESULTS All patients with documented TRAS underwent PTA. Two purely technical failures occurred. In one case we were unable to cross a stenosis with a balloon catheter, and in the other a balloon ruptured. Both lesions were successfully dilated on subsequent attempts. Ten lesions had a greater than 20% residual stenosis, including the two previously mentioned technical failures. Thus, technical success was achieved in 14 of 24 procedures (58%).A further breakdown of technical results reveals less than 20% residual stenosis in 14 (58%),between 20% and 50% residual stenosis in four (17%), and greater than 50% stenosis in six (25%).Restenosis occurred in two patients with main renal artery stenosis 4 months after PTA, and both were successfully treated with repeat PTA.
The average mean diastolic blood pressure was 106 mm Hg (range, 88120 mm Hg) 1day prior to PTA and was 81 mm Hg (range, 70-92 mm Hg) 1day after PTA. Mean blood pressure at 1week was 84 mm Hg (range, 70-92 mm Hg). At follow-up (average, 11.5 months; range, 2-32 months), diastolic blood pressure was 93 mm Hg (range, 70-112 mm Hg). The mean number of blood pressure medications prescribed decreased from 2.4 (range, one to five) prior to PTA to 1.4 (range, zero to three) at hospital discharge. The number of blood pressure medications was decreased in 13 patients and unchanged in five. Fifteen of 18 patients (83%)experienced a 10% or greater reduction in mean blood pressure 1week following PTA. Long-term follow-up (average, 11.5 months; range, 2-32 months) showed 11of 18 (63%)had a persistent 10% or greater decrease in mean blood pressure. Among these 11patients, six also were taking fewer blood pressure medications. Among the seven patients with no long-term change in blood pressure, the number of blood pressure medi-
Matalon et a1
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a. b. c. Figure 2. (a)Right external iliac DSA image obtained from a patient with a single renal transplant. Stenoses of the main renal artery and its proximal branch are seen. (b) During PTA, kissing balloons were placed across the lesion and in the adjacent branch. ( c ) After PTA, there is complete resolution of the branch stenosis. Blood pressure prior to angioplasty was 1501108 and after angioplasty was 132190 mm Hg.
cations was decreased in six. The BUN level decreased from 44.6 mg/dL (15.9 mmol/L) (range, 14-105 mg/dL L5.0-37.5 mmol/L]) before PTA to 39 mg/dL (13.9 mmol/L) (range, 9-56 mg/dL [3.2-20 mmol/ Ll) after PTA. The creatinine level decreased from 2.6 mg/dL (230 kmol/L) (range, 0.8-5.7 mg/dL [70500 kmol/Ll) to 2.0 mg/dL (180 kmol/L) (range, 0.8-4.0 mg/dL [70350 pmol/LI). At follow-up, BUN and creatinine levels were decreased by 10% or greater in nine patients (50%),were unchanged in seven (39%), and were increased in two (11%). Biopsy in the latter two cases showed acute tubular necrosis in one and chronic rejection in the other. For two of the four patients with decreasing renal function at presentation, BUN and creatinine levels decreased; for the other two, the levels remained unchanged. One patient required surgical evacuation of a groin hematoma and repair of the site of an inadvertent femoral venous puncture following a technically successful common iliac and main renal artery PTA procedure. A second major complication was a 20% polar infarct following suc-
cessful dilation of a main renal artery lesion. Blood pressure control became difficult. In this patient, graft function was lost subsequent to a bizarre allergic reaction following an insect bite 8 months after PTA. Minor complications included three groin hematomas and a small pseudoaneurysm at the puncture site. None became clinically apparent nor required additional intervention. Long-term patient follow-up information from 2 to 72 months (mean, 23.3 months) after PTA is available in all patients. Two patients have died: one of multiple myeloma and one of sepsis unrelated to PTA. Two patients have lost renal function because of chronic rejection and require hemodialysis. Two others underwent repeat transplantation: one for chronic rejection and one after the previous described anaphylactic reaction. The remaining 12 patients retain renal transplant function without dialysis. Transplant biopsies were performed in 13 patients. Twelve showed evidence of rejection, and one showed acute tubular necrosis. Four patients with rejection have died or lost graft function.
DISCUSSION PTA has become a safe and effective therapy for TRAS. Other large series have reported clinical improvement in 63%-76% of patients (3,643). A recent report challenges the efficacy and safety of PTA for TRAS. In that report, clinical improvement was achieved in only 20% of patients, with a very high rate of serious complications (seven of 31, 22.5%) (2). This was not our experience. A complication requiring surgical intervention occurred in only one of 24 procedures. A second complication (polar infarct) significantly changed the patient's course. No surgical revisions of the transplant renal artery were necessary. A major difference between our series and that of Roberts et a1 (2) is the location of the lesion. The majority of lesions in their study were anastomotic (24 of 31, 77%),while only two anastomotic lesions (11%) were present in our series. Others have reported lower success rates with anastomotic lesions (9). Chandrasoma and Aberle reported histologic differences between anastomotic
58
Journal of Vascular and Interventional Radiology
February 1992
lesions and nonanastomotic lesions (10). However, comparable success rates for PTA of anastomotic and nonanastomotic lesions have also been reported (3,6). Anastomotic lesions may be secondary to surgical technique (1,ll ) , while nonanastomotic lesions may have an immunologic origin (12). Our study does not address this issue, as the population is skewed toward nonanastomotic lesions. However, the fact that 12 of 18 patients in our study had biopsy evidence of rejection does favor an immunologic mechanism for nonanastomotic lesions. While our study does not directly compare results of PTA and surgical correction, it does support the use of PTA for nonanastomotic lesions. Surgical success ranges from 7.5% to 75%, with major complications i n 0%-15% (1,2,13-16). Our results are comparable. Our technical success rate was 58%. Clinical success is difficult to define. A complete cure (patient is normotensive without receiving blood pressure medication) is rare and unexpected given the multiple causes of posttransplant hypertension. We consider a 10% reduction in diastolic blood pressure to be a significant improvement. This often reduced diastolic blood pressure from above 100 to below 100 mm Hg. The Hypertension Detection and Follow-up Program Cooperative Group showed a significantly lower longterm morbidity and mortality when the diastolic blood pressure was in the range of 90-104 mm Hg versus above 104 mm Hg (17).Also a reduction of number of blood pressure medications may have a major effect on the patient. These patients are often taking multiple medications, and a decrease in the number of blood pressure medications may help reduce morbidity from drug interactions. We were not as successful in improving renal function in those patients presenting with decreasing renal function. Two of four had a 10% reduction in BUN and creatinine levels. All four patients had biopsy evidence of chronic rejection. This may
contribute to the lower success rates in these patients. Roberts et al reported a major complication rate of 22.5% (graft loss or emergency intervention required). Our major complication rate was much lower; 8.3% (two of 24 procedures), with no periprocedural graft loss and only one emergent non-graft intervention required. It is not known why anastomotic lesions are associated with a higher major complication rate, although the resistant nature of the lesions may necessitate using 7-F stiffer systems with an attendant increase in morbidity. Most of our procedures were performed using 5-F or coronary systems. Our data indicate that PTA should remain the treatment of choice for nonanastomotic TRAS. The procedure is relatively safe, and clinical success rates are comparable to those achieved with surgical correction. References 1. Lacombe M. Arterial stenosis complicating renal transplantation in man: a study of 38 cases. Ann Surg 1975; 181:283-288. 2. Roberts JP, Ascher NL, Fyrd DS, et al. Transplant renal artery stenosis. Transplantation 1989; 48:580583. 3. Greenstein SM, Verstandig A, McLean GK, et al. Percutaneous transluminal angioplasty. Transplantation 1987;43:29-32. 4. Aliabadi H, McLorie GA, Churchill BM, et al. Percutaneous translumind angioplasty for transplant renal stenosis in children. J Urol 1990; 143:569-573. 5. Standards of Practice Committee of the Society of Cardiovascular and Interventional Radiology. Guidelines for percutaneous transluminal angioplasty.JVIR 1990; 1:5-15. 6. Clements R, Evans C, Salaman JR. Percutaneous transluminal angioplasty of renal transplant artery stenosis. Clin Radio1 1987;38:235-237. 7. Mollenkopf F, Matas A, Spragregen S, et al. Percutaneous transluminal angioplasty for transplant renal artery stenosis. Transplant Proc 1983; 15:1089-1091. 8. Raynaud A, Bedrossian J, Remy P, et al. Percutaneous transluminal angioplasty of renal transplant arte-
rial stenosis.AJR 1986; 1469353857. Grossman RA, Dafoe DC, Schoenfeld RB, et al. Percutaneous transluminal angioplasty treatment of renal transplant artery stenosis. Transplantation 1982; 34:339-343. Chandrasoma P, Aberle AM. Anastomotic line renal artery stenosis after transplantation.J Urol 1986; 135:1159-1162. Oakes DD, Spees EK, McAllister HA, et al. Arterial injury during perfusion preservation: a possible cause of post-transplant renal artery stenosis. Surgery 1981; 89:210-213. Sniderman KW, Sprayregen S, Sos TA, et al. Percutaneous transluminal dilation in renal transplant arterial stenosis. Transplantation 1980; 30:440443. Osborn DE, Castro JE, Shackman R. Surgical correction of arterial stenosis in renal allografts. Br J Urol 1976; 48:221-224. Smith RB, Cosmi AB, London R, et al. Diagnosis and management of arterial stenosis causing hypertension after successful renal transplantation. J Urol 1979; 115:639643. Minda R, Alexander JW, Miller S, et al. Renal allograft artery stenosis. Am J Surg 1977; 134:400403. Kauffman HM, Sampson D, Fox PS, et al. Prevention of transplant renal artery stenosis. Surgery 1977; 81:161-163. Hypertension Detection and Follow-up Program Cooperative Group. Five-year findings of hypertension detection and follow-up program. JAMA 1979; 242:2562-2571.
