Predictors Of Graft Occlusion Research Articles

Intraoperative Transit-Time Flow as a Predictor of Failure after Infrainguinal Revascularization with Heparin-Bonded Expanded Polytetrafluoroethylene Graft

The heparin-bonded expanded polytetrafluoroethylene (He-ePTFE) conduit is an option for patients requiring infrainguinal revascularization (iIR), but the risk of failure may be unpredictable, especially in cases with poor run-off. Intraoperative transit-time flow (TTF) provides an automated and quantitative analysis of flow and may serve as an adjunct evaluation during surgical revascularization. The aim of this study was to assess TTF in patients undergoing iIR with He-PTFE at 3 referral hospitals and to establish a predictive flow threshold for graft occlusion. A prospective registry initiated in 2020 enrolled patients undergoing iIR using He-PTFE for critical limb ischemia or severe claudication, and TTF measurement was analyzed. Preoperative assessments of anatomical and clinical characteristics were available for all patients. The HT353 Optima Meter (Transonic Systems Inc., Ithaca, NY, USA) was used in all procedures according to a standardized protocol. The institutional ethics committee approved the study. A predictive model using receiver operating characteristic curve analysis was utilized to establish the threshold of flow, and variables were compared. Anatomical and clinical evaluation were reported according to Rutherford grade, Global Limb Anatomic System and Wound, Ischemia, and foot Infection classification. The main outcome considered was the correlation between TTF and graft occlusion. Secondary outcomes included survival, other predictors of graft occlusion, freedom from major adverse cardiovascular events, and freedom from major amputation. Among 68 patients, 55.8% had Rutherford 5-6, 45.6% had Global Limb Anatomic System 3 and 73.5% had Wound, Ischemia, and foot Infection 3-4. Distal anastomosis was at tibial level in 23.5% and mean diameter of conduit was 6.4mm. Basal and postoperative TTF were 27.8±15.6ml/min and 109.0±53.0 ml/min, respectively. After a mean follow-up of 18±13months, 7 (10.9%) patients presented graft occlusion and 5 (7.8%) required major amputation. TTF threshold=80ml/min revealed a sensitivity and specificity of 81.8% (95% confidence interval 48.2-97.7) and 80.7% (95% confidence interval 68.1-90.0) respectively, and it was selected as cut-off for graft occlusion. Freedom from graft occlusion in patients with TTF >80ml/min vs. TTF ≤80ml/min at 6, 12, and 24months was 95.7% (standard error (SE)=0.030) vs. 65.5% (SE=0.115), 95.7% (SE=0.030) vs. 58.9% (SE=0.120) and 90.9% (SE=0.054) vs. 51.6% (SE=0.126), P=0.0003. No statistical difference in primary patency, secondary patency and limb salvage was observed. At multivariate analysis, distal anastomosis at tibial vessel (odds ratio 8.50) and TTF ≤80ml/min (odds ratio 9.39) were independent predictors of graft occlusion. These results suggest that TTF may serve as a valuable tool in the management of iIR. A TTF measurement of ≤80ml/min should be regarded as a predictor of graft occlusion, prompting consideration of additional intraoperative maneuvers to enhance arterial flow. Caution should be exercised in patients requiring direct tibial artery revascularization, as it represents a predictor of failure independent of TTF levels. Larger cohorts of patients and longer follow-up periods are necessary to confirm these findings.

P4740Clinical predictors of graft occlusion after coronary artery bypass grafting: a case-control study

Abstract Objective Coronary artery bypass grafting (CABG) is still one of the most common surgical procedures aimed at improving blood circulation in atherosclerotic coronary arteries.Graft occlusion influences outcome CABG. The risk factors of long-term graft occlusion remain uncertain.The aim of the present study was to investigate the clinical predictors of graft occlusion after CABG. Methods All patients with prior CABG in our center who underwent coronary computed tomography angiography (CTA) and/or percutaneous coronary angiography for follow-up between Aug 2013 and Dec 2017 were included in the present study. We excluded patients who underwent multiple CABG surgeries or percutaneous coronary intervention after index CABG. With regard to one patient with two or more different angiography results, we selected the angiography result which showed graft occlusion for the first time or the last angiography result. The baseline clinical data at index CABG was analyzed for their independent impact on graft occlusion in a case-control study using multivariate logistic regression. Results 1178 (27.5%) of 4289 patients experienced at least one graft occlusion. The mean age was 63.23±9.02 years, 1004 (23.4%) patients were female. From all the occlusion cases, artery occlusion occurred in 337 (28.6%) patients and saphenous vein graft occlusion occurred in 875 (74.3%) patients.Complete baseline data was available for evaluation from 1178 of them (case group). We matched these patients through gender, age and time interval between the index CABG and angiography/CTA to another 1178 patients who did not have graft occlusion (control group). After multivariate logistic regression, chronic renal dysfunction (OR=1.008; 95% CI, 1.001–1.021; P=0.038) hyperuricemia (OR=1.89; 95% CI, 1.101–3.876; P=0.040) and hyperlipemia (with low density lipoprotein increased) (OR=1.377; 95% CI, 1.021–1.926; P=0.042) significantly increased the risk of long-term graft occlusion. Conclusions Chronic renal dysfunction hyperurcemia and hyperlipemia were independent risk factors of long-term graft occlusion. Acknowledgement/Funding National Key Research and Development Program of China (2017YFC0908800)

Bleeding and Thrombotic Outcomes Associated With Postoperative use of Direct Oral Anticoagulants After Open Peripheral Artery Bypass Procedures

The widespread use of the direct oral anticoagulants (DOACs) for the treatment of atrial fibrillation and venous thromboembolism has inevitably resulted in peripheral bypass patients receiving therapeutic anticoagulation (AC) with DOACs postoperatively. No recommendations exist to guide whether DOACs can be safely used as an alternative to vitamin K antagonists (VKAs) for prophylaxis of high-risk bypass grafts. This study was undertaken to evaluate the bleeding and thrombotic outcomes of patients undergoing open peripheral bypass treated with DOACs compared with VKAs. We examined data from a large, statewide, multicenter quality improvement vascular surgery registry of all patients undergoing elective, urgent, or emergent peripheral bypass operations between January 2012 and December 2017. Outcomes included length of stay, transfusion, readmission, return to operating room, 1-year primary patency, and major amputation within 1 year. Statistical significance between treatment groups was determined using pairwise Wilcoxon rank-sum tests for continuous variables and pairwise χ2 or Fisher exact tests for categorical variables. Multivariate logistic regression was performed for bleeding complications and graft occlusion. Post hoc pairwise comparisons for treatment groups were calculated using Tukey’s P value adjustment. In total, 9682 patients met our inclusion criteria. Postoperatively 7605 patients received no AC, 1456 received a VKA, and 621 a DOAC. Patients receiving AC were older, had a higher body mass index, and were more likely to have preoperative anemia, hyperlipidemia, hypertension, congestive heart failure, coronary artery disease, and atrial fibrillation (all P < .05). Compared with patients treated with VKA, patients treated with DOACs were less likely to have valvular disease and chronic renal insufficiency and more likely to have atrial fibrillation (all P < .05). The length of stay (LOS) varied significantly among treatment groups, with the shortest length of stay in patients receiving no AC (median, 5 days; interquartile range [IQR], 3-9; P < .001), followed by DOACs (median, 6 days; IQR, 3-11; P < .001) and the longest LOS observed in patients treated with VKAs (median, 8 days; IQR, 5-13; P < .001). Perioperative transfusion was significantly higher in patients treated with VKAs (33.9%), compared with DOAC (28.7%; P = .023) and no anticoagulant (23.8%; P < .0001). Primary patency at 1 year did not differ among groups. Return to the operating room for graft occlusion (3.5% VKA, 3.4% DOAC vs 1% no AC; P < .001) and amputation (19.2% VKA, 17.1% DOAC, vs 11.9% no AC P < .001) was higher in patients receiving AC compared with those not receiving AC, regardless of type (VKA compared with DOAC). On multivariate analysis, procedure status (emergent: odds ratio, 2.31 [95% CI, 1.39-3.84; P = .001], urgent: odds ratio, 1.60 [95% CI, 1.04-2.45; P = .032]) were predictors of graft occlusion. No AC patients were less likely to experience graft occlusion (odds ratio, 0.40 [95% CI 0.27-0.59; P < .001]). Among a mixed group of patients undergoing lower extremity bypass, those treated with a DOAC postoperatively had a shorter LOS and were less likely to receive a transfusion in the perioperative setting without compromising graft patency or affecting amputation rate when compared with those treated with VKA. These data suggest the need for a prospective trial evaluating DOAC safety and efficacy in patients requiring AC for high-risk bypass grafts.

Endovascular Treatment of Popliteal Artery Aneurysms: A Word of Caution after Long-Term Follow-up

The aim of this work was to evaluate the long-term patency of endografting in the treatment of popliteal artery aneurysms (PAAs) and to identify which factors may be predictors of graft occlusion. All the patients who underwent endovascular repair of PAA were analyzed from 2006 until 2014 on the basis of symptoms, comorbidities, limb salvage, and long-term patency. The predictive value of the different variables was assessed in univariate analysis for primary patency and, for factors resulted significant, a multivariate analysis was performed. The Kaplan-Meier life table method was used to calculate patency and limb salvage. We treated 65 PAAs in 57 patients (53 men and 4 women). PAAs were symptomatic in 26 cases (40%) and 34% were the emergency cases; the mean aneurysm size was 33.8±17mm. Mean follow-up was 35months±25. Graft occlusion occurred in 22 limbs (35%). We had 9 amputations (14.5%). The late conversion to open surgery was 6.4%. The cumulative estimated 60-month primary patency, secondary patency, and limb salvage were respectively 57% (standard error [SE] ±0.7), 73% (SE ±0.7), and 83% (SE ±0.5). We found that diabetes (hazard ratio [HR] 2.936, 95% confidence interval [CI] 0.993-8.683), associated percutaneous transluminal angioplasty (PTA) procedures (HR 2.534, 95% CI 1.115-5.757), symptoms (HR 2.492, 95% CI 1.127-5.510), and runoff scores (HR 2.069, 95% CI 0.942-4.544) were the most important risk factors for long-term patency at univariate analysis. When considering a multivariate analysis symptoms (HR 2.066, 95% CI 0.862-4.952) become the principal risk factor followed by diabetes (HR 1.808, 95% CI 0.531-6.157)], runoff scores (HR 1.716, 95% CI 0.757-3.893) and associated PTA procedures (HR 1.441, 95% CI 0.519-3.839), but no one reached a statistical significance. On the base of our experience it seems that several factors affect durability in PAA endovascular repair, especially the presence of acute symptoms, diabetes, and runoff. Therefore until further refined clinical studies, we believe that the actual role of this technique must be yet clarified.

Short- and long-term results of radial artery and saphenous vein grafts in the right coronary system: a propensity-matched study.

The selection of optimal grafts for the right coronary artery remains controversial. This study aims to evaluate the short- and long-term results of radial artery (RA) grafts and saphenous vein grafts (SVGs) to the right coronary artery. We reviewed, retrospectively, isolated coronary artery bypass grafts, placed between 1997 and 2007, and compared the long-term results of patients who received RA (n=110) grafts with those of patients who received SVGs (n=264)using propensity-score matching for risk. The preoperative predictors of graft occlusion were investigated on a per case basis. Superior survival was noted in the unmatched RA group, but late outcomes after propensity-score matching yielded 91 patient pairs that were similar in the two groups. Graft failure was not correlated with mortality, but showed strong correlation with cardiac events in all patients. The predictors of graft occlusion in the RA group were mild proximal stenosis and low indexing glomerular filtration rates for body surface area, whereas those in the SVG were female gender and off-pump coronary artery bypass grafting. There were no significant differences in long-term outcomes between the RA and SVG groups. Predictors of graft occlusion differed between the groups. Notably, renal dysfunction impaired radial patency, emphasizing the importance of careful graft selection.

Aspirin plus clopidogrel for optimal platelet inhibition following off-pump coronary artery bypass surgery: results from the CRYSSA (prevention of Coronary arteRY bypaSS occlusion After off-pump procedures) randomised study

ObjectiveTo determine the individual variability in the response to aspirin and/or clopidogrel and its impact on graft patency after off-pump coronary artery bypass grafting.DesignA single-centre prospective randomised controlled study designed...