Richard A. Yeager

Accuracy of lower extremity arterial duplex mapping

We performed lower extremity arterial duplex mapping from the aortic bifurcation to the ankle in 150 consecutive patients evaluated for aortic and lower extremity arterial reconstruction and compared lower extremity arterial duplex mapping in a blinded fashion to angiography. On the basis of history, physical examination, and four-cuff segmental Doppler pressures individual lower extremities were classified as normal, isolated aortoiliac disease, infrainguinal disease, and multilevel inflow and outflow disease. For vessels proximal to the tibial arteries, lower extremity arterial duplex mapping was analyzed for its ability to insonate individual arterial segments, detect a 50% or greater stenosis, and distinguish stenosis from occlusion. In the tibial arteries lower extremity arterial duplex mapping was evaluated for its ability to visualize tibial vessels and to predict interruption of tibial artery patency from origin to ankle. Lower extremity arterial duplex mapping visualized 99% of arterial segments proximal to the tibial vessels, with overall sensitivities for detecting a 50% or greater lesion ranging from 89% in the iliac vessels to 67% at the popliteal artery. Stenosis was successfully distinguished from occlusion in 98% of cases. In the tibial vessels lower extremity arterial duplex mapping was better at visualizing anterior tibial and posterior tibial artery segments (94% and 96%) than peroneal artery segments (83%), (p less than 0.001). Overall sensitivities for predicting interruption of tibial artery patency were 90% for the anterior tibial, 90% for the posterior tibial, and 82% for the peroneal. Clinical disease category did not influence in a major way the accuracy of lower extremity arterial duplex mapping in either above-knee or below-knee vessels.

Mesenteric duplex scanning: A blinded prospective study☆☆☆

PURPOSE Based on retrospective comparisons of duplex scanning with arteriography of the celiac (CA) and superior mesenteric (SMA) arteries in 34 patients, we previously suggested that an SMA peak systolic velocity of 275 cm/sec or greater or no flow signal and a CA PSV of 200 cm/sec or greater or no flow signal were reliable indicators of a 70% or greater angiographic stenosis of the SMA and CA, respectively. We now report the results of a blinded, prospective study in a larger patient group designed to determine the ability of mesenteric duplex scanning to visualize the CA and SMA and to validate our proposed duplex criteria for splanchnic artery stenosis. METHODS During an 18-month period 100 patients admitted to our vascular surgery service for aortography underwent routine mesenteric artery duplex scanning and lateral abdominal aortography regardless of abdominal symptoms. The lateral aortograms were evaluated to determine the presence or absence of a 70% or greater stenosis in the CA or SMA. Duplex-determined peak systolic velocities from the CA and SMA were recorded without knowledge of the angiographic results. RESULTS Aortography satisfactorily visualized 100% of the CAs and 99% of the SMAs. Of these, 93% of the SMAs and 83% of the CAs were visualized by duplex. According to the above criteria, duplex sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy for detection of a 70% or greater SMA stenosis were 92%, 96%, 80%, 99%, and 96% and for a 70% or greater CA stenosis 87%, 80%, 63%, 94%, and 82%. CONCLUSIONS Mesenteric duplex scanning is feasible in the majority of patients. Prospective evaluation of duplex diagnostic criteria for 70% or greater stenosis indicates that mesenteric duplex scanning is sufficiently accurate to be clinically useful as a screening examination to detect SMA and CA stenosis.

Duplex ultrasound criteria for diagnosis of splanchnic artery stenosis or occlusion

Mesenteric artery duplex scanning appears promising for detection of splanchnic artery stenosis or occlusion or both in patients with symptoms suggestive of chronic intestinal ischemia. However, no specific duplex criteria have been developed for detection of mesenteric artery stenosis. We obtained mesenteric artery duplex scans and infradiaphragmatic lateral aortograms in 34 patients to determine duplex criteria for mesenteric stenosis. Seventy percent or greater angiographic stenosis was present in 10 superior mesenteric arteries and 16 celiac arteries. Duplex scans were reviewed to determine if celiac artery and superior mesenteric artery ratios of peak systolic velocities and end-diastolic velocities to peak aortic systolic velocity, as well as celiac artery and superior mesenteric artery peak systolic velocities and end-diastolic velocities alone, could predict a greater than or equal to 70% angiographic stenosis or occlusion or both. The results obtained by use of receiver operator curves indicated peak systolic velocity alone was an accurate predictor of splanchnic artery stenosis. Specifically, a peak systolic velocity greater than or equal to 275 cm/sec in the superior mesenteric artery and greater than or equal to 200 cm/sec in the celiac artery or no flow signal (superior mesenteric artery and celiac artery) predicted a 70% to 100% stenosis with sensitivity, specificity, and positive predictive values of 89%, 92%, and 80% for the superior mesenteric artery. Similar values for the celiac artery were 75%, 89%, and 85%, respectively. End-diastolic velocities or calculated velocity ratios conveyed no additional accuracy in predicting splanchnic artery stenosis.

Improved results with conventional management of infrarenal aortic infection

PURPOSE Interest in alternative methods, such as autogenous vein grafts and aortic allografts, for the management of infrarenal aortic infection (IRAI) has been stimulated by the historically disappointing results with conventional surgical management. Recently, there have been dramatic improvements in the results of axillofemoral bypass grafting (AXFB) followed by excision of the IRAI that have gone relatively unrecognized. The purpose of this report is the presentation of modern-day results in the treatment of IRAI with conventional surgical methods. METHODS From January 1, 1983, through June 30, 1998, patients with IRAI underwent treatment with AXFB and complete excision of the IRAI. The patients were followed for survival, limb salvage, and AXFB graft patency. The results were tabulated with life-table methods. RESULTS During the 15-year study period, 60 patients (51 men, nine women; mean age, 68 years) underwent treatment for IRAI (50 graft infections, including 16 graft-enteric fistulae, and 10 primary aortic infections). The mean follow-up period was 41 months. The perioperative mortality rate was 13% (12% for graft infection, and 20% for primary infection). The overall 2-year and 5-year survival rates were 67% and 47%, respectively. The limb salvage rates at 2 and 5 years were 93% and 82%, respectively. The 5-year primary AXFB graft patency rate was 73%. CONCLUSION These results show an improvement with the conventional management of IRAI equal or superior to those results reported with alternative methods, including femoral vein grafts or aortic allografts. These results should be regarded as the modern standard with which alternative therapies can be compared.

Surgical management of severe acute lower extremity ischemia

Seventy-four patients (70 men [95%], 4 women [5%], mean age, 63 years) with severe, acute lower limb ischemia (acute clinical deterioration and absent pedal Doppler signals) caused by either arterial thrombosis (n = 68) or embolism (n = 6) underwent urgent surgical management consisting of operative revascularization with or without amputation in 67 patients (91%) and primary amputation alone in 7 patients (9%). Sixty-one patients (82%) had severely threatened limb viability, and 13 (18%) had major irreversible ischemic limb changes at presentation. Eighty-six percent of patients were initially anticoagulated with heparin. Seventy percent underwent preoperative angiography. Surgical revascularization included 42 inflow and 20 outflow arterial reconstructions and 9 thrombectomy or embolectomy procedures. Mean follow-up was 17 months (range, 0 to 64). Life-table primary patency at 36 months for arterial reconstructions was 81% for inflow and 78% for outflow procedures. Cumulative limb salvage was 70% at 1 month and 68% at 36 months. Patient survival was 85% at 1 month and 51% at 36 months. No death was directly attributable to complications related to limb reperfusion, and no patient required dialysis for myoglobinuria. We conclude that management of severe, acute lower limb ischemia with early amputation of nonviable limbs and heparinization, angiography, and prompt operative revascularization for threatened but viable extremities minimizes morbidity and mortality rates, while maximizing limb salvage. These results may be useful for comparison with comparable groups of patients treated with thrombolytic or endovascular modalities.

Comparison of axillofemoral and aortofemoral bypass for aortoiliac occlusive disease

PURPOSE A comparison of aortofemoral bypass grafting (AOFBG) and axillofemoral bypass grafting (AXFBG) for occlusive disease performed by the same surgeons during a defined interval forms the basis for this report. METHODS Data regarding all patients who underwent AOFBG of AXFBG for lower-extremity ischemia caused by aortoiliac occlusive disease were prospectively entered into a computerized vascular registry. The decision to perform AOFBG rather than AXFBG was based on assessment of surgical risk and the surgeons preference. This report describes results for surgical morbidity, mortality, patency, limb salvage, and patient survival for procedures performed from January 1988 through December 1993. RESULTS We performed 108 AXFBGs and 139 AOFBGs. AXFBG patients were older (mean age, 68 years compared with 58 years for AOFBG, p<0.001), more often had heart disease (84% compared with 38%, p<0.001), more often underwent surgery for limb-salvage indications (80% compared with 42%, p<0.001). No significant differences were found in operative mortality (AXFBG, 3.4%; AOFBG, <1.0%, p=NS), but major postoperative complications occurred more frequently after AOFBG (AXFBG, 9.2%; AOFBG, 19.4%; p<0.05). Follow-up ranged from 1 to 83 months (mean, 27 months). Five-year life-table primary patency, limb salvage, and survival rates were 74%, 89%, and 45% for AXFBG and 80%, 79%, and 72% for AOFBG, respectively. Although the patient survival rate was statistically lower with AXFBG, primary patency and limb salvage rates did not differ when compared with AOFBG. CONCLUSION When reserved for high-risk patients with limited life expectancy, the patency and limb salvage results of AXFBG are equivalent to those of AOFBG.

The incidence of perioperative myocardial infarction in general vascular surgery

In a 1-year period all patients undergoing general vascular surgery (491 patients, 534 procedures) underwent monitoring by creatine phosphokinase isoenzymes and electrocardiograms (ECG) to detect perioperative myocardial infarction. Only those patients with severe symptomatic coronary artery disease (31 patients, 5.8%) characterized by unstable angina pectoris, uncontrolled arrhythmia, or severe congestive heart failure had any testing for coronary artery disease beyond history, physical examination, and ECG. Only three patients (0.5%) had prophylactic coronary artery bypass performed before general vascular procedures. Twenty-one (3.9%) myocardial infarctions (five asymptomatic, detected by enzymes only, and 16 symptomatic, four of which were fatal) were associated with the 534 procedures (aorta 105, carotid 87, infrainguinal bypass 207, extraanatomic 51, other 84). Eight noncardiac perioperative deaths occurred. All operative deaths (12 of 534, 2.2%) including all four fatal myocardial infarctions occurred associated with surgery on an urgent or emergency basis (12 of 249 procedures, urgent/emergent operative mortality rate 4.8%). No operative deaths and no fatal myocardial infarctions associated with the 285 elective procedures occurred. Nine of the 17 nonfatal myocardial infarctions (53%) also occurred after urgent/emergent procedures. The rate of perioperative myocardial infarctions (eight of 285, 2.8%) after elective surgery in this patient series is no different from that reported by multiple recent authors advocating widespread screening for and prophylactic treatment of coronary artery disease before general vascular surgery. Our experience confirms the therapeutic approach that expensive and invasive coronary screening programs in patients to undergo vascular operations should be limited to carefully selected patients with severely symptomatic coronary disease.

Improving survival and limb salvage in patients with aortic graft infection

A 15-year experience with 38 aortic graft infections, including 15 patients with graft enteric fistulas, is reviewed in order to analyze modern-day surgical results utilizing extra-anatomic bypass and aortic graft excision. Perioperative mortality was 14% during the most recent 7-year interval, which was a notable improvement compared with the earlier time interval (p = 0.06). Extended follow-up of the perioperative survivors demonstrated a 77% cumulative 5-year survival and a 76% cumulative 5-year limb salvage rate. Subsequent axillofemoral graft infection occurred in 22% of survivors and resulted in a significantly higher amputation rate compared with those patients with no axillofemoral graft infection (p less than 0.001). The results suggest good perioperative and long-term survival in patients with aortic graft infection, with excellent limb salvage if subsequent axillofemoral graft infection can be avoided.

Aortic and peripheral prosthetic graft infection: Differential management and causes of mortality☆

This report of 25 patients with prosthetic graft infection has compared the diagnosis, management, and outcome in 14 patients with infected aortic grafts with 11 patients with infected peripheral grafts (two axillofemorofemoral, five femorofemoral, five femoropopliteal, and one femoral interposition). Peripheral graft infection had a significantly shorter interval to diagnosis compared with aortic graft infection. Total graft removal combined with either autogenous revascularization or extraanatomic bypass using prosthetic graft was performed in all 14 patients with infected aortic grafts. Management of peripheral graft infection consisted of total graft removal in eight patients (four with autogenous revascularization and two with amputation) and partial graft removal in three patients (two with amputation). Mortality and amputation rates for infected aortic grafts were 43 percent and 25 percent, respectively compared with 36 percent and 27 percent for infected peripheral grafts. Recommendations for management of the infected aortic prosthetic graft include total graft removal, but methods and timing of revascularization are dependent on the specific features of the individual case. However, preferred management for the infected peripheral prosthetic graft includes total graft removal and, if indicated, revascularization using autogenous tissue.

Noninvasive localization of arterial occlusive disease: A comparison of segmental Doppler pressures and arterial duplex mapping

PURPOSE The purpose of this study was to compare the abilities of arterial duplex mapping and segmental Doppler pressures to noninvasively localize hemodynamically significant lower extremity arterial occlusive disease. METHODS After angiographic controls were instituted, arterial duplex mapping and segmental Doppler pressures were blindly compared for their ability to localize a high-grade (50% to 100%) stenosis to the iliac or common femoral arteries, the superficial femoral artery, or the popliteal artery in 151 lower extremities from 79 patients. RESULTS Rates of sensitivity and specificity of arterial duplex mapping for identifying a high-grade stenosis at the three arterial levels were 88% and 97%, 95% and 100%, and 78% and 99%, respectively. Those for segmental Doppler pressures were 59% and 86%, 73% and 80%, and 48% and 53%, respectively. There was complete agreement between arterial duplex mapping and angiography in 82% of the limbs studied and between segmental pressures and angiography in 34% of the limbs (p < 0.0001). The presence of diabetes, kidney failure, or previous vascular surgery in the limb studied did not affect the accuracy of either test. CONCLUSION Arterial duplex mapping is far superior to segmental Doppler pressures for localization of high-grade angiographic lesions from the iliac to the popliteal arteries.