The New England Society for Vascular Surgery: on the first quarter century.
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History, 20th Century↗
Biomedical subjects
N P Couch
Publications and source records attributed to N P Couch.
What is the proper role of polytetrafluoroethylene grafts in infrainguinal reconstruction?
Polytetrafluoroethylene grafts have been used extensively for infrainguinal vascular reconstruction either as the conduit of choice or as a substitute when saphenous vein is unavailable. Although numerous studies have shown satisfactory early patency rates, the long-term efficacy of these grafts in a large number of patients for specific indications and in various positions has been less well defined. From 1977 to 1987 we used four PTFE grafts from three different manufacturers to perform 300 infrainguinal reconstructions on 240 patients on our vascular service. The indications for surgery were disabling claudication in 28% and limb salvage in 72%. The 30-day operative mortality of 1% was not different from the 1.4% associated with infrainguinal autogenous vein grafting. The 5-year cumulative patency rate achieved with all infrainguinal polytetrafluoroethylene grafts was 35%, significantly higher for grafts placed for claudication (57%) than those placed for limb salvage (24%). There were no significant differences between the above-knee and below-knee locations for distal anastomoses regardless of indication, but femoropopliteal grafts provided significantly higher 5-year patency (37%) than infrapopliteal grafts (12%). Comparison of the 5-year patency rates among the three manufacturers of polytetrafluoroethylene grafts showed no significant differences. Fifty-four polytetrafluoroethylene grafts that failed underwent 67 revisions after catheter thrombectomy or thrombolysis, which resulted in a minimal 11% 5-year patency rate. Based on this experience, it is concluded that infrainguinal polytetrafluoroethylene prostheses provide significantly inferior results when compared with autogenous reconstruction.
Adult↗
About heparin, or ... whatever happened to Jay McLean?
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Heparin↗
Resource-based relative values for invasive procedures performed by eight surgical specialties.
We surveyed approximately 850 physicians in eight surgical specialties to investigate physicians' work in performing invasive services. Building on our analysis of physician work, we developed a relative value scale of physicians' services based on resource costs. First, we found that physician charges are not set in proportion to the resources required to perform a given procedure: there is a threefold variation, across hospital-based invasive procedures, in the ratio of charges to resource-based relative values. Second, for most procedures, the preoperative and postoperative periods represent 60% to 75% of a physician's total service time, but only 35% to 50% of the total service work. Lastly, intraoperative work per unit of time varies greatly. Work per minute for invasive procedures is two to three times that of medical office visits and is strikingly greater for some specialties. The Resource-Based Relative Value Scale, at a minimum, represents a useful tool for payers to identify procedures with potentially aberrant charges and also offers unique insights into the nature of physicians' work.
Ambulatory Surgical Procedures↗
Femoropopliteal reconstruction for claudication. The risk to life and limb.
The current study was undertaken to examine the results of femoropopliteal bypass grafting with intermittent claudication as the indication. Of 1173 infrainguinal reconstructions carried out on our service during the past decade, 249 (21%) consecutive femoropopliteal grafts were performed for disabling claudication in 191 patients. The primary five-year cumulative patency rates were 78% for autogenous vein and 52% for polytetrafluoroethylene grafts. There were two (0.8%) 30-day operative deaths and a subsequent five-year amputation rate of 2.4% for both groups. Femoropopliteal reconstruction for claudication may therefore be carried out with acceptably low operative mortality and a subsequent amputation rate comparable with that anticipated from the natural history of the disease. While the five-year patency rate is significantly higher utilizing autogenous vein grafts, symptomatic relief may be expected with prosthetic grafts in approximately half the patients without incurring a higher risk of limb loss.
Adult↗
Thrombolysis in the treatment of peripheral arterial vascular occlusions.
The efficacy of thrombolytic agents in the management of peripheral arterial disease remains unclear. We reviewed our experience with 64 consecutive episodes of limb-threatening graft or native vessel occlusions. The overall success rate was 59%, with a major complication/mortality rate of 28%. Thrombolytic therapy in patients with occluded vascular grafts required identification of a causative lesion and subsequent adjunctive management with percutaneous transluminal angioplasty or surgery for sustained patency (64%). In contrast, approximately 70% of native vessel occlusions maintained patency whether a causative lesion was identified and corrected or not. Patients who failed thrombolytic therapy had a worse prognosis overall, with 38% undergoing primary amputation, although patients with reconstructable occlusions still had a 64% salvage rate at six months. The review demonstrated that thrombolytic therapy continues to be a useful adjunct in treating the patient with peripheral vascular occlusion, although a significant risk of major complications persists. Patients with graft occlusions successfully treated with thrombolysis require correction of any precipitating lesions for long-term limb salvage, while careful management of patients failing thrombolysis can still achieve significant limb salvage in selected cases.
Aged↗
A comparison of in situ and reversed saphenous vein grafts for infrainguinal reconstruction.
Despite the recent popularity of the in situ saphenous vein graft for infrainguinal arterial reconstruction, considerable doubt exists as to whether this approach offers any real advantage over conventional reversed vein grafts. Therefore we have reviewed our experience with 675 infrainguinal vein grafts undertaken during the past 10 years. There have been no substantial modifications in the technique used for 535 reversed vein grafts over the 10-year period. During the past 3 years, 140 in situ vein grafts have been carried out with the Leather valvulotome used to incise the venous valves. Life-table analysis of 449 femoropopliteal reversed saphenous vein grafts demonstrated 1- and 3-year cumulative patency rates of 81% and 73%, respectively, and a 5-year patency rate of 63%. Seventy-five femoropopliteal in situ bypasses demonstrated a patency rate of 85% at both 1- and 3-year intervals. Cumulative patency rates for 86 femoroinfrapopliteal reversed saphenous vein grafts were 64% and 62% at 1 and 3 years, respectively. Comparable patency rates for 65 infrapopliteal in situ saphenous vein grafts remained stable at 87% for 3 years. Fifteen of the in situ bypasses were anastomosed to vessels at the ankle or foot level, whereas none of the reversed bypasses was carried that far distally. This experience with both in situ and reversed techniques on one service by the same surgeons demonstrates a clear superiority of the in situ saphenous vein graft for infrapopliteal reconstruction at the 3-year interval.
Actuarial Analysis↗
Recognition and management of impending vein-graft failure. Importance for long-term patency.
A previous report from this group indicated a very poor long-term patency rate (19%) for occluded femoro-distal vein grafts that require initial thrombectomy prior to patch angioplasty for documented stenosis. Patients with vein grafts were therefore followed up by Doppler pressure determinations of the ankle/brachial index (ABI) postoperatively at three weeks, six weeks, and every four months thereafter for two years in an effort to identify vein-graft failure prior to actual thrombosis. During the past six years we performed 322 vein grafts of which 29 grafts were identified by diminished Doppler ABI and were found to have stenotic segments on subsequent arteriography. Twenty-two of these patients (group 1) underwent reconstruction with patch angioplasty resulting in a five-year cumulative patency rate of 82%. The remaining seven patients (group 2) underwent percutaneous transluminal angioplasty of their stenotic segments yielding a significantly lower five-year patency rate of 43%. These two groups were compared with a third group fo 25 patients with thrombosed grafts mandating initial thrombectomy prior to patch angioplasty. The thrombectomized group 3 patients demonstrated a significantly lower five-year cumulative patency rate of 28%. These data suggest that patients with femoro-distal bypass vein grafts be followed up at frequent intervals early in their postoperative course with determinations of Doppler ABI measurements. Any significant reduction in Doppler ABI compared with the highest postoperative Doppler determination should be aggressively evaluated with digital-subtraction or routine angiography in an effort to locate a stenotic lesion prior to graft thrombosis. Patients found to have such a graft stenosis are then ultimately treated with patch angioplasty in anticipation of satisfactory long-term patency rates.
Angiography↗
On the arterial consequences of smoking.
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Adult↗
Abdominal aortic aneurysm repair in patients with preoperative renal failure.
The purpose of this study was to determine the effect of preoperative renal failure on the outcome of patients undergoing infrarenal abdominal aortic aneurysm (AAA) repair. Of 251 patients undergoing AAA repair from 1977 to 1984, 10% had evidence of preoperative chronic renal failure. These patients were classified according to their preoperative serum creatinine values; group I had preoperative creatinine levels of 2 to 4 mg/dl, group II had creatinine levels greater than 4 mg/dl but no history of hemodialysis, and group III consisted of patients on chronic hemodialysis before operation. One of 16 patients in group I developed transient high-output renal failure postoperatively. Four of the six patients in group II (67%) developed significant postoperative deterioration of renal function and required acute hemodialysis. Of the four patients in group III maintained on chronic hemodialysis preoperatively, one died of sepsis from an ischemic colon. This experience suggests that patients with mild renal dysfunction (serum creatine value less than 4 mg/dl) can undergo elective AAA repair without additional morbidity. Patients on hemodialysis before operation can also safely undergo surgical repair of their AAAs electively if dialyzed the day before operation. Patients with severe renal dysfunction (serum creatinine greater than 4 mg/dl) who are not on hemodialysis should be considered for dialysis preoperatively in an attempt to reduce the high incidence of serious postoperative renal functional deterioration and subsequent morbidity.
Aorta, Abdominal↗
Coronary artery disease in patients requiring abdominal aortic aneurysm repair. Selective use of a combined operation.
The chief cause of operative mortality after abdominal aortic aneurysm (AAA) repair is myocardial infarction. For this reason, routine coronary angiography followed by prophylactic coronary artery bypass grafting (CABG) prior to AAA repair has been recommended by some surgeons. We report here the results of the selective use of a combined operation. Two hundred twenty-seven patients had elective or emergency repair of nonruptured AAA on our service from 1972 to 1983. Prior to surgery, all patients underwent careful clinical evaluation for the presence of coronary artery disease (CAD) and were classified into the following: group I (n = 121), no clinical evidence of CAD, 53%; group II (n = 96), clinical evidence of stable CAD, symptomatic or asymptomatic, 42%; group III (n = 10), unstable CAD, five per cent; Group IIIa (n = 4), asymptomatic AAA; and group IIIb (n = 6), symptomatic AAA. Seven patients ultimately assigned to group II underwent stress electrocardiogram (ECG) and eight group II patients had coronary angiography before surgery. All patients in groups I and II underwent elective or urgent repair of their AAA without CABG. Prior to surgery, these patients were managed with placement of a pulmonary artery catheter and incremental volume loading to construct a left ventricular performance curve as a guide to surgical fluid replacement. All were carefully monitored for at least 48 hours after surgery in an intensive care unit. Four patients (group IIIa) with unstable CAD and asymptomatic AAA underwent CABG followed by elective AAA repair within six months. Six patients (group IIIb) with unstable CAD and symptomatic AAA underwent combined open heart surgery (CABG and, in one patient, valve replacement) and AAA repair as a single operation. There was no operative mortality in group III patients. Thirty-day operative mortality for the entire group of 227 patients was 1.3% (three deaths), with only one death from a myocardial infarction (0.4%). While there is clearly a high incidence of CAD in patients with AAA, the present results indicate that these individuals can be managed with low risk by a selective approach based upon clinical assessment of their CAD. Our experience further demonstrates that patients with unstable CAD and symptomatic AAA may have both lesions safely repaired as a single operative procedure.
Adult↗
Treatment of arterial occlusive disease of the lower extremities.
The surgical management of arterial occlusive disease of the lower extremities is reviewed, with emphasis on extra-anatomic and reoperative methods. Consideration is given to alternative interventional radiologic techniques, both as definitive therapy as well as in conjunction with conventional surgical reconstruction.
Angioplasty, Balloon↗
The iliac-origin arterial graft: a useful alternative for iliac occlusive disease.
The results of ilioiliac and iliofemoral bypass grafts were compared with those for aortic-origin grafts in 205 patients and 332 legs operated upon for aortoiliac occlusive disease since 1972. Poor-risk patients who had a patent distal aorta and at least one functionally patent proximal iliac artery were considered for reconstruction with the iliac artery used for the proximal anastomosis. The procedure, performed through a retroperitoneal approach, has several technical advantages and is especially satisfactory for patients who would otherwise have an axillofemoral graft. The data indicate that these iliac-origin reconstructions compare favorably in patency with aortic-origin reconstructions or with other "extra-anatomic" arterial reconstructions, enabling extremely low morbidity and mortality rates even in high-risk patients.
Aorta↗
Effect of aspirin and dipyridamole on the patency of lower extremity bypass grafts.
Recent clinical studies indicate that the use of aspirin and dipyridamole improves graft patency rates in patients with infrainguinal polytetrafluoroethylene (PTFE) grafts and aortocoronary vein grafts. We undertook a prospective, double-blind, randomized study to determine whether these drugs administered postoperatively to patients with PTFE or autologous vein infrainguinal bypasses would improve graft patency during the first 24 months after operation. Patients received either aspirin 325 mg and dipyridamole 75 mg or identical placebo tablets three times a day, taken orally. Patency rates were compared by computing standard life tables and comparing cumulative patency rates. One hundred patients with 102 grafts were studied. The cumulative patency rate at 24 months was not significantly different for the treatment (57%) versus control (67%) groups or for any subgroup. We conclude that aspirin and dipyridamole administered postoperatively in the doses used in this study do not improve the overall patency rates of vein or PTFE infrainguinal bypass grafts.
Aged↗
Early carotid endarterectomy in patients with small, fixed neurologic deficits.
Patients who have sustained a large hemispheric stroke are not candidates for early carotid endarterectomy, but there is less agreement regarding the role of carotid endarterectomy in patients with small, fixed neurologic deficits. Accepted practice in many centers is to wait 4 to 6 weeks after the onset of the deficit before proceeding with carotid endarterectomy because of the fear that early revascularization will increase the size of the infarct. Earlier endarterectomy, however, in patients with significant residual ipsilateral carotid territory at risk may prevent repeated infarctions. For the past 5 years our approach to patients with a small stable stroke and significant stenosis (greater than 75%) has been prompt ipsilateral endarterectomy. Of the 337 carotid endarterectomies at our institution since 1979, a subset of 28 patients with hemodynamically significant carotid lesions presented with a small, fixed stroke. The period of time between the appearance of the stroke and carotid endarterectomy averaged 11 days, but 53% of patients were operated on within 7 days of the onset of symptoms. Selective shunting based on intraoperative EEG monitoring was utilized and 40% of the 28 patients required shunts. Operative mortality consisted of one death from a pulmonary embolus, and no patient sustained a new postoperative deficit. Long-term follow-up was available for 96% of patients over a mean of 2 years. During this time two new neurologic events occurred: one fatal stroke and one transient deficit. This experience indicates that patients with small, fixed neurologic deficits who continue to have carotid territory at risk may safely undergo carotid endarterectomy without waiting 4 to 6 weeks.
Aged↗
The place of abdominal aortography in abdominal aortic aneurysm resection.
We analyzed 110 patients who underwent abdominal aortography as a routine preliminary to abdominal aortic aneurysm resection. In 11 of the 15 patients for whom the procedures were useful in planning the operative tactics, the aortograms would have been performed anyway on clinical indications. In two patients, the changes in surgical maneuvers would not have been made through anatomic inspection at the time of the operations, but the lesions were asymptomatic. Biplane views and views of the femoropopliteal systems were rarely influential. Morbidity from the angiography was minimal and mortality was zero, but about seven aortograms were performed for each one that effected a change in procedure. We concluded that abdominal aortography as a preliminary to aneurysmectomy could be reasonably limited to patients in whom it was indicated by clinical features, including important hypertension, impaired renal function, diminished or absent femoral pulses, suspected mesenteric ischemia, suspected suprarenal extension of the aneurysm, or suspected (from the chest roentgenograms) thoracic aneurysm.
Aorta, Abdominal↗
Coexistent carotid and coronary artery disease. Surgical management.
We performed simultaneous coronary artery bypass grafting (CABG) and carotid endarterectomy (CE) in 42 patients (average age, 61 years). Twenty-nine patients had preoperative transient ischemic attacks. Carotid arteriography showed stenosis (greater than 70%) in 38 subjects and extensive ulcerated lesions in two, and two emergency patients were not studied. Carotid artery dissection and sternotomy were simultaneously performed and the patients were cannulated for cardiopulmonary bypass (CPB). We undertook CE (22 left and 24 right) using EEG monitoring prior to CPB in all but one patient. The average carotid occlusion time was 25 minutes without a shunt in 23 patients and 5.5 minutes with a shunt in 19 patients. After CE, CABG was performed with an average aortic clamp time of 39 minutes and an average CPB time of 87 minutes. The operative mortality was 5% (2/42). There were no strokes or perioperative myocardial infarctions. Neurologic morbidity consisted of postoperative headache in one patient, transient upper-extremity weakness in two patients, and transient facial weakness in one patient. The average length of postoperative hospitalization was ten days. Currently, patients with symptomatic coronary artery disease and concomitant carotid bruits with positive noninvasive testing and arteriography should have simultaneous repair of these lesions.
Aged↗
The fate of bypass grafts to an isolated popliteal artery segment.
From 1967 to 1982, 55 patients underwent 64 femoropopliteal bypass grafts into an isolated popliteal artery segment. Seventy-six percent of these patients had threatened limb loss from advanced atherosclerosis, and 24% had disabling claudication. Forty-five percent of the patients were diabetic. The 30-day operative mortality rate was 1.6%, and the 30-day postoperative amputation rate was 3.2%. Graft potencies were analyzed by the life table method. The 2-year graft patency rate was 70.6%, and the 5-year patency was 60.7%. The 2- and 5-year limb salvage rates were each 83%. With evidence for decreased graft function, four grafts (6%) were successfully revised before failure occurred. Among 10 polytetrafluoroethylene grafts followed up to a maximum of 48 months, there was one early postoperative occlusion, one long-term occlusion, and one early amputation. With respect to patency and limb salvage, the results of isolated popliteal artery segment grafts fall between the 5-year patency and limb salvage rates for autogenous vein grafts to popliteal arteries with at least one tibial vessel runoff (78% patency and 89% limb salvage) and the rates for femoral-tibial/peroneal grafts (5-year patency 56%, limb salvage 69%). An isolated segment is an appropriate recipient vessel for a reconstruction for limb salvage, and reasonably good results can be anticipated.
Actuarial Analysis↗