Postoperative predictive value of a new method of intraoperative angiographic assessment of runoff in femoropopliteal bypass grafting

Endovascular Recanalization of the Chronically Occluded Native Superficial Artery After Failed Bypass Graft: Midterm Results

PURPOSE

To evaluate the safety, effectiveness, and outcomes of endovascular recanalization of chronic total occlusion (CTO) of the superficial femoral artery (SFA) in patients with critical limb ischemia (CLI) after failed surgical bypass graft.

METHODS

Endovascular recanalization of SFA CTO was performed for 26 consecutive CLI patients with failed bypass grafts from 2016 to 2020. Patient demographics, bypass and lesion characteristics, procedural data, technical, and clinical outcomes were evaluated.

RESULTS

The technical success rate was 96.2% (25/26). Retrograde arterial access was used in 16 (61.6%) patients. Additional tibial and iliac angioplasty was performed in 15 and 2 patients, respectively. Fifteen complications occurred in 10 patients, including thrombosis, embolism, vessel rupture, dissection, arteriovenous fistula, and pseudoaneurysm. Pain relief and wound healing were achieved in 22 patients. The primary, assisted primary, and secondary patency rates were 95.5%, 100%, and 100% at 6 months, 81.8%, 95.5%, and 100% at 12 months, and 76.7%, 82.7%, and 87.5% at 24 months, respectively. By univariate analysis, hyperlipidemia (hazard ratio = 7.82; 95% CI: 1.27-48.04, P = .026) was found to be the only significant risk factor related to primary patency loss. Amputation-free survival and limb salvage rates were 100% and 100% at 6 months, 100% and 100% at 12 months, and 87.1% and 93.8% at 24 months, respectively.

CONCLUSIONS

Endovascular recanalization of SFA CTO in CLI patients with graft failures is effective with high technical success rates. Acceptable limb salvage and amputation-free survival rates make this technique a reasonable alternative to repeat surgery for high-risk patients.

Intraoperative angioscopy may improve the outcome of in situ saphenous vein bypass grafting: a prospective study

OBJECTIVE

To find out whether intraoperative angioscopic assistance has any effect on graft outcome in patients with critical leg ischemia.

MATERIAL AND METHODS

One hundred one patients requiring a below-knee bypass were assigned to undergo in situ saphenous vein bypass with or without intraoperative angioscopic assistance; otherwise treated similarly including preoperative duplex vein mapping, intraoperative graft flow measurements, and angiography. Data on operative details, morbidity, hospital stay, and graft patency were collected prospectively and compared. All patients were followed up for 12 months.

RESULTS

The group that underwent angioscopy (A) and the control group (B) were similar in all respects, except for the number of patients enrolled in the groups (32 and 69, respectively). Angioscopy revealed incompletely destructed valves in 34 patients (range, 0 to 5; mean 1), undiagnosed vein branches in 111 patients (mean 4.3), and partly occluding thrombus in 5 patients. The number of postoperative arteriovenous fistulas with signs of failing graft and a need for angiographic or surgical reintervention were significantly higher in group B (P <.0001). The 1-year primary patency rate was significantly better in group A (P <.01), but the primary assisted and secondary patency rates did not differ between the groups.

CONCLUSIONS

Angioscopic assistance has an impact on primary graft patency, minimizes the risk for graft failure and thus reduces the need for reintervention by allowing identification of persistent saphenous vein branches, incomplete valve destruction, and partly occluding graft thrombus without adding extra operative time.

Distal percutaneous transluminal angioplasty through infrainguinal bypass grafts

AIM

to evaluate the results of transluminal angioplasty (PTA) performed through infrainguinal bypass grafts for stenotic or occlusive lesions at the distal anastomosis and/or in the runoff arteries.

DESIGN

retrospective clinical study.

MATERIAL AND METHODS

forty-one patients underwent 57 procedures at the distal anastomosis (n=13), in the runoff arteries (n=32) or at both locations (n=12) at a median of 9.6 months (range, 2-76 months) after infrainguinal bypass grafting. Nineteen procedures were on the popliteal artery, the rest on the crural arteries. Eleven procedures related to occlusions less than 5 cm in length.

RESULTS

technical success was achieved in 91%. Primary and primary assisted graft patency rates at 3 years were 32% and 53%, respectively. There were no significant differences in patency rates with regard to the graft material, the type of lesion, the level of PTA, the status of runoff and the use of thrombolysis before PTA. No patients underwent amputation as a direct consequence of failed PTA or graft occlusion. One patient underwent acute surgical intervention due to graft occlusion at the time of attempted PTA.

CONCLUSION

the results of PTA at the distal anastomosis and/or in the runoff arteries in limbs with infrainguinal bypass seemed to be inferior to the results of surgical revisions reported in literature. However, as failed PTA did not jeopardise vein-patch angioplasty or jump grafting, it is a reasonable alternative to surgical intervention in selected cases.

The influence of distal runoff on patency of infrainguinal vein bypass grafts

This retrospective study was conducted to analyze a new concept of evaluation of the effect of distal runoff on patency in infrainguinal bypass surgery for arterial insufficiency. Distal runoff was evaluated on postreconstruction angiograms in 191 limbs undergoing femoropopliteal and femorodistal reconstruction. Runoff was characterized as good, fair, or poor. Determination of graft patency was made by clinical examination, ankle-brachial index measurement, or duplex scanning at 1 month and thereafter at 6-month intervals. Cumulative patency rates were calculated according to the actuarial life table method. Patency rates in limbs with good runoff were better than in limbs with fair and poor runoff; at 6 months, patency rates were 88.2%, 70.9%, and 21.8%, respectively (p < 0.01). Similar patency rates were found for good runoff in femoropopliteal and femorodistal reconstructions (84.7% in femoropopliteal and 75% in femorodistal reconstructions) at 6 months. The authors conclude that this method of angiographic evaluation accurately predicts patency in infrainguinal bypass reconstructions.

Prediction of the immediate outcome of femoropopliteal saphenous vein bypass by angiographic runoff score

OBJECTIVES

To determine the value of the Ad Hoc scoring system (SVS/ISCVS) in predicting the immediate outcome of femoropopliteal saphenous vein grafts.

DESIGN

Retrospective study.

MATERIALS

One hundred and twenty patients underwent 132 primary femoropopliteal vein bypass procedures, 32 for claudication and 100 for critical leg ischemia (CLI).

METHODS

The outflow arteries were graded according to the Ad Hoc scoring system (SVS/ISCVS). Postoperative immediate graft patency and leg salvage to the period of the first 30 days after surgery.

RESULTS

Ninety-one per cent of claudicants and 83% of CLI patients had immediate patency. The overall 30-day patency rate was 85%. Leg salvage rate was 91% for the patients with CLI. Patients with score in the highest quartile were found to have a 8.7 times higher risk for immediate graft occlusion (p = 0.005). Multivariate analysis showed that the Ad Hoc score was predictive of immediate patency (p = 0.0006) and leg salvage (p = 0.0004). In patients with a score < or = 7.5 and in those with a score > 7.5, the patency rates were 95% and 66% (p = 0.001), and the leg salvage rates were 97% and 80%, (p = 0.004), respectively.

CONCLUSIONS

The Ad Hoc scoring system is useful in predicting the immediate outcome of femoropopliteal saphenous vein grafts.

Composite polytetrafluroethylene/vein bypass grafts: conventional distal vein segment or vein cuff?

OBJECTIVES

To determine the current status of PTFE vein composite grafts, we reviewed our experience with 205 composite reconstructions and compared the results of conventional distal vein segment to that of distal vein cuff.

DESIGN

Retrospective review.

SETTING

Department of Surgery, University Hospital.

PATIENTS AND METHODS

The series included 85 women and 102 men with a median age of 70. The indications for surgery were claudication in 30, rest pain in 71 and ulcer/gangrene in 103. The site of the distal anastomosis was the popliteal artery in 111 and crural artery in 94. The graft consisted of a proximal PTFE graft anastomosed to a distal segment of reversed saphenous vein in 169 or to a modified distal Miller cuff in 36 operations after 1992.

RESULTS

Cumulative life table primary patency rates for the whole series at 12, 24 and 36 months were 39%, 32% and 25% respectively. Limbs with good run-off demonstrated significantly better patency rates compared to limbs with poor run-off (55% and 17% at 12 months, 35% and 11% at 36 months, p = 0.04). The patency rate of femorocrural grafts with poor run-off was only 4% at 12 months. The overall limb salvage rates at 12 and 36 months were 63% and 55%, respectively. Similar results were obtained in limbs with distal reversed vein segment and distal vein cuff.

CONCLUSION

The results of this study suggest that for infrainguinal bypass grafting where the saphenous vein is unavailable, a composite PTFE-vein graft might be an acceptable alternative in limbs with good run-off. Although not a randomised study, the results using a distal reversed vein segment of a cuff were similar.

Value of duplex scanning in evaluation of crural and foot arteries in limbs with severe lower limb ischaemia--a prospective comparison with angiography

OBJECTIVES

To compare Duplex scanning with angiography for evaluation of crural and pedal arteries in limbs with lower limb ischaemia.

DESIGN

The findings obtained during Duplex scanning and angiography were prospectively compared in a blinded manner.

SETTING

Departments of Surgery, Diagnostic Radiology and Clinical Physiology, University Hospital.

MATERIALS

Duplex scanning and selective angiography of femoropopliteal, crural and foot arteries were performed in 40 limbs (38 patients, 480 segments) with intermittent claudication (n = 6), rest pain (n = 13) and ulcer/gangrene (n = 19). Each arterial segment were graded into four categories: normal, < or = 50% diameter reduction, > 50% diameter reduction and occlusion. Pedal arteries were evaluated as patency or occlusion of dorsal pedal artery and plantar arch.

CHIEF OUTCOME MEASURES

Accuracy (AC), sensitivity (SE), specificity (SP), positive predictive (PPV), negative predictive (NPV) and kappa values.

MAIN RESULTS

The Duplex scanning of the tibioperoneal trunk, crural and pedal arteries had an accuracy of 80% (kappa = 0.6). The SE, SP, PPV and NPV values were 83%, 77%, 79% and 81%, respectively. The SP was relatively low for the peroneal artery (58%) compared to the others.

CONCLUSIONS

The results demonstrate the feasibility and reliability of Duplex scanning in detecting crural and pedal artery lesions in lower limbs with severe ischaemia.

The "ad hoc" estimation of outflow does not predict patency of infrainguinal reconstructions

OBJECTIVES

This prospective study was performed to evaluate the clinical implication of the adhoc estimation (also called SVS score) of outflow on patency of infrainguinal in situ femoropopliteal or -distal bypasses.

METHODS

The bypasses were followed with Duplex scanning at 1, 3, 6, and 12 months after surgery. Fifty-three bypasses were recruited for the study, 20 of which were performed in 17 diabetics. In 47% the adhoc scoring was < or = 4.5 and in 53% it was between 5 and 10 (1 corresponds to an excellent outflow and 10 to a blind segment).

RESULTS

Within the first 30 days eight occlusions occurred, all of which were surgically corrected. The adhoc score for these bypasses was 4.2 vs. 4.9 (NS) for those who did not occlude. During follow-up, revisions were performed in 21 cases (40%) with 30 interventions. At the end of 1 year, 68% of the bypasses were patent (80% among diabetics and 64% among non-diabetics, NS). Patency at 1 year was not influenced by the adhoc classification.

CONCLUSION

The estimation of outflow from angiography seems to be of no value in predicting graft patency in infrainguinal grafting.

Influence of anatomic distribution of atherosclerosis on the outcome of revascularization with iliac stent placement

PURPOSE

To determine the influence of clinical and angiographic variables, including the anatomic disease pattern, on the outcome of iliac stent placement.

PATIENTS AND METHODS

The 455 patients of the study population were divided in three groups according to the anatomic distribution of their peripheral atherosclerosis lesions. Pattern type 1 (focal aortoiliac and/or common iliac lesion) included 180 patients (39.6%), type 2 (external iliac lesion) comprised 58 patients (12.8%), and type 3 (multilevel lesions) included 217 patients (47.7%).

RESULTS

Complete relief of symptoms immediately after revascularization was observed in 88.3% and 85.4% of patients with pattern type 1 and 2, respectively, compared to 60.1% with type 3 (P < .05). The persistence of clinical benefit at 36-month follow-up was 91.6%, 97.9%, and 60.8% in disease patterns 1, 2, and 3, respectively. The overall 1-year mortality rate was 3% with type 1 lesions, 5.7% with type 2, and 9.7% with type 3. On multivariate logistic regression, the presence of a disease pattern type 3 was the most powerful indicator (P < .001) of early unsatisfactory clinical outcome in iliac stent placement. Unexpectedly, female gender was predictive of unsatisfactory clinical outcome (P < .01) and higher periprocedural complications (P < .001) following iliac stent revascularization.

CONCLUSIONS

Pattern type classification helps identify patients at higher risk for cardiovascular morbidity and mortality. Ideal candidates for iliac stent placement are patients with pattern type 1 or 2 disease.

Comparative analysis of patency, limb salvage and survival in diabetic and non-diabetic patients undergoing infrainguinal bypass surgery

In 92 diabetic and 175 non-diabetic patients undergoing 336 femoropopliteal or femorodistal bypass procedures, 1- and 3-year cumulative life-table patency, limb salvage, and survival rates were comparatively analysed. The peroperative mortality rate was significantly higher in diabetic patients (5% compared to 1.4%, p < 0.001). The cumulative graft patency rates were 61% at 12 months and 46% at 36 months in diabetic patients compared to 64 and 52% in non-diabetic patients. Significantly better patency rates were observed in limbs with good runoff compared to limbs with poor runoff in both groups. The limb salvage rates at 3 years were 70% in diabetic patients and 62% in non-diabetic patients. The survival rate at 3 years was significantly lower in diabetic patients, 62% compared to 86% in non-diabetic patients. Diabetic patients with poor runoff demonstrated a significantly lower survival rate after 36 months compared to diabetic patients with good runoff (48% and 74%, respectively). The results of this study demonstrate that the early and intermediate patency and limb salvage rates are similar in diabetic and non-diabetic patients. On the other hand the survival rate in diabetic patients, especially in those with poor distal runoff, is significantly lower than non-diabetic patients.

Late graft failure of autologous vein grafts for arterial occlusive disease: clinical and experimental studies

Late graft failure following arterial reconstructive surgery, especially after infrainguinal reconstruction, remains a major concern for vascular surgeons. To more effectively predict the outcome of reconstructed arteries, we herein propose an intraoperative flow waveform analysis which correlates well with the long-term patency rate of grafts. According to this flow waveform analysis, late graft failure was occasionally seen in grafts with type II waveforms when poor distal runoff vessels had been shown by the preoperative arteriogram. Next, to investigate which events occurring in autologous vein grafts under abnormal hemodynamics may contribute to late graft failure, a distal poor-runoff model was made in the canine femoral artery. In this review, we present the results of our investigation on autologous vein grafts using this poor-runoff model. We also relate our recent findings on the function of regenerated endothelium in autologous vein grafts.

The effect of postocclusion reactive hyperaemia, papaverine and nifedipine on duplex derived haemodynamic parameters of infrainguinal bypass grafts

OBJECTIVES

The aim of the present study was to analyse the effects of various vasodilating stimuli on postoperative infrainguinal graft haemodynamics.

DESIGN

Duplex derived haemodynamic parameters of infrainguinal bypass grafts were measured at rest and after postocclusion reactive hyperaemia, intraarterial papaverine (40 mgm) injection and peroral nifedipine (10 mg) administration.

SETTING

Department of Surgery, University Hospital.

MATERIALS

Twenty-nine patients with infrainguinal bypass grafts were studied by Duplex scanner after a median of 25 months postoperatively.

CHIEF OUTCOME MEASURES

Peak systolic velocity (PSV), mean velocity (MV) and volume flow (VF) were measured at rest and after various stimuli.

MAIN RESULTS

VF at rest increased from 125 +/- 16 ml/min (mean +/- S.E.M.) to 271 +/- 26 ml/min after papaverine administration and to 205 +/- 19 ml/min during reactive hyperaemia (p < 0.001). PSV, MV and VF increased significantly during postocclusion reactive hyperaemia and papaverine injection. After nifedipine administration VF increased to 154 +/- 21 ml/min after 30 min (p < 0.001) and there was a significant increase in MV (p < 0.05).

CONCLUSIONS

Duplex derived flow measurement of infrainguinal bypass grafts can evaluate graft and limb haemodynamics in the postoperative period. Pharmacological manipulations, such as vasodilation, can influence the physiological runoff with subsequent increase in volume flow through the graft.

Femoropopliteal bypass with either adequate ipsilateral reversed saphenous vein or obligatory polytetrafluoroethylene

The results are presented of a 10-year experience with 312 femoropopliteal bypasses performed in 285 patients using ipsilateral autologous reversed greater saphenous vein when available and adequate and polytetrafluoroethylene (PTFE) when not. The indications for operation were severe claudication in 121 (39%), rest pain in 95 (30%), and minor tissue loss in 96 (31%) limbs. There were 235 (75%) saphenous vein bypasses, of which 157 were above and 78 below the knee, and 77 (25%) PTFE bypasses, 58 above and 19 below the knee. Of these, 232 (79%) saphenous vein and 62 (21%) PTFE bypasses were primary procedures. The 30-day mortality rate was 3% (7/285) and the 30-day amputation rate was 2% (6/312). Overall, 24 (10%) saphenous vein and 30 (39%) PTFE grafts ultimately failed. The cumulative primary patency of all bypasses was 77% +/- 4% (mean +/- 1 SE) (85% to 69%, 95% confidence interval) at 3 years and 75% +/- 4% (86% to 64%) at 5 years. Saphenous vein primary patency was superior to that of PTFE at 3 years, 87% +/- 4% (97% to 77%) vs. 54% +/- 12% (65% to 41%), (p < 0.01), and at 5 years, 81% +/- 6% (96% to 67%) vs. 48% +/- 16% (63% to 33%) (p < 0.01). Above-knee saphenous vein bypass primary patency was slightly better than below-knee patency at 3 years, 89% +/- 4% vs. 84% +/- 6%, and at 5 years, 83% +/- 7% vs. 80% +/- 8%. This was superior to above-knee PTFE patency at 3 years, 54% +/- 14%, and at 5 years, 34% +/- 16% (p < 0.01). The overall PTFE failure rate was three to four times that of the saphenous vein rate. These results strongly support the use of autologous greater saphenous vein for all femoropopliteal bypasses when it is available and of good quality. PTFE grafts are valuable secondary conduits when the vein is not available or is inadequate. This series was not randomized since PTFE was used only in patients with inadequate or unavailable ipsilateral greater saphenous veins. When this protocol was followed, the patency rate for greater saphenous vein was excellent and its use is recommended for femoropopliteal bypass when it is available and of good quality.

Impact of angioscopy on infrainguinal graft patency

To investigate the impact of angioscopy on infrainguinal graft patency, 50 consecutive cases with angioscopy as an adjuvant to infrainguinal arterial bypass performed during a 12-month period were reviewed (group I). For comparison, 42 similar cases of infrainguinal arterial reconstruction performed during the 12 months prior to introduction of routine intraoperative angioscopy were also reviewed (group II). Patients were followed up for 12 months and graft patency was determined at 1, 3, 6, and 12 months. An abnormality was identified in 13 (26%) group I patients (10, angioscopy alone; 1, arteriography alone; 2, both). Defects were anastomotic abnormalities (n = 7), vein sclerosis (n = 3), retained valve cusp (n = 2), and proximal artery stenosis (n = 1). A similar percentage, but different types of defects, were seen in group II; 11 patients (26%) had an abnormality (anastomotic abnormality [n = 3], vein sclerosis [n = 4], retained valve cusp [n = 1], and arterial outflow stenoses [n = 3]). All significant defects were surgically explored and corrected. Graft patency rates in group I and II at 1, 3, 6, and 12 months were 100% and 85% (P < 0.005), 94% and 80% (P < 0.05), 87% and 74% (P = non-significant [NS]), and 86.1% and 73.7% (P = NS), respectively. Intraoperative angioscopy detects anastomotic and vein graft defects not always seen on arteriography; the repair of these defects significantly improves early infrainguinal bypass graft patency rates.

Computer-assisted modeling of blood-flow: theoretical evidence for the existence of optimal flow wave patterns

The purpose of this study was to model blood-flow waveforms in order to examine the relationship between various waveform shapes and input impedance spectra. Twenty distinct single cardiac cycle flow waveforms having the same mean flow and heart rate were created based on clinical and published observations. The "best" waveform was one with a steep flow upstroke, a high peak flow value, swift deceleration following peak flow, and flow reversal during diastole. Each flow waveform was paired with 20 computer-generated pressure waveforms to calculate input impedance spectra by discrete Fourier transformation. "Favorable" flow waveforms were associated consistently with a lower characteristic impedance (average of 4th-10th harmonics, Zav) irrespective of the shape or magnitude of the input pressure wave. Zav corresponds to the degree of compliance of the vascular bed and could be expected to be lower under favorable outflow conditions and in non-diseased vessels. In conclusion, this study provides theoretical evidence for the existence of optimal flow wave patterns and supports the notion of flow waveform assessment for diagnostic purposes.

Are there angiographic predictors of success for vein bypass to the peroneal artery?

In order to evaluate the effect of angiographic run-off upon peroneal artery autogenous vein bypass patency and subsequent limb salvage, 53 autogenous vein peroneal artery bypasses performed for ischemic tissue loss were reviewed. All preoperative angiograms were evaluated according to three separate angiographic scoring systems that previously had been designed to quantify the severity of runoff resistance. None of the three scoring systems predicted either early bypass occlusion and/or major amputation. The cumulative 18-month primary patency and 24-month secondary patency rates were 71% and 90%, respectively. The 24-month limb salvage rate was 81%. Initial and intermediate-term salvage of limbs with ischemic tissue loss can be achieved by peroneal artery bypass. Angiographic scoring systems were poor predictors of bypass failure or major amputation.

Angiographic assessment of arterial outflow: predictive value of a new classification system

A prospective study with 4 years of follow-up involving 127 consecutive symptomatic patients (60.6% with claudication, 39.4% with critical ischemia) who underwent aortobifemoral bypass surgery is described. A new grading system for the classification of arterial outflow was applied to determine its usefulness in predicting the outcome of surgery. Preoperative angiograms were numerically scored according to the arterial outflow status at the level of main segmental involvement. Higher scores corresponded to worse outflows. Outflow scores ranged between 1 and 10 with a mean of 3.6 +/- 0.24. The main comparison was between patients with scores of less than 5 (group A, n = 80) and patients with scores of 5 or more (group B, n = 47). Better outflow was associated with higher postoperative mean increases in the ankle-brachial index (ABI) (group A, 0.35 +/- 0.03; group B, 0.17 +/- 0.04; P less than .001) and transcutaneous oximetry (PtcO2) (group A, 15.4 mm Hg +/- 1.8; group B, 8.4 mm Hg +/- 3.0; P = .01). At 4-year follow-up, group A had higher cumulative rates of patency (98.3% vs 78.0%, P less than .001), symptomatic relief (84.0% vs 23.3%, P less than .001), and palliation (67.0% vs 19.9%, P less than .001). In conclusion, angiographic outflow, as evaluated with the system described, successfully helped predict postoperative increases in ABI and PtcO2 and the cumulative rates of graft patency, symptomatic relief, and palliation.

Bypass grafting to the popliteal artery in limbs with occluded crural arteries

Intraoperative completion angiograms of 47 femoropopliteal bypasses in limbs with occluded crural arteries were reviewed to identify the angiographic determinants of early outcome. Of 28 limbs in which the foot vessels were available for analysis, only 2 (7%) had an intact pedal circulation, and 18 limbs demonstrated no crural arteries suitable for distal reconstruction. The overall cumulative patency rate was 51% with a 76% limb salvage rate at 12 months. All seven grafts performed onto a popliteal artery segment of less than 8 cm occluded in the early period. The status of crural and foot arteries and the number of collaterals did not correlate well with early patency. Limbs with no patent crural artery that were analyzed in the poor angiographic runoff group, according to our previously reported classification, demonstrated relatively higher patency rates than the other subgroups with poor runoff. In cases where angiography demonstrates a poor runoff for distal revascularization, popliteal bypass with occluded crural arteries might achieve acceptable patency rates.