Thromboelastography after Cardiopulmonary Bypass: Does it Save Blood Products?

Introduction. This study aimed to determine if thromboelastography (TEG) is associated with reduced blood product use and surgical re-intervention following cardiopulmonary bypass (CPB) compared to traditional coagulation tests. Methods. A retrospective review was conducted of 698 patients who underwent CPB at a tertiary-care, community-based, university-affiliated hospital from February 16, 2014 – February 16, 2015 (Period I) and May 16, 2015 - May 16, 2016 (Period II). Traditional coagulation tests guided transfusion during Period I and TEG guided transfusion during Period II. Intraoperative and postoperative administration blood products (red blood cells, fresh frozen plasma, platelets, and cryoprecipitate), reoperation for hemorrhage or graft occlusion, duration of mechanical ventilation, hospital length of stay and mortality were recorded. Results. Use of a TEG-directed algorithm was associated with a 13.5% absolute reduction in percentage of patients requiring blood products intraoperatively (48.2% vs. 34.7%, p <0.001). TEG resulted in a 64.3% and 43.1% reduction in proportion of patients receiving FFP and platelets, respectively, with a 50% reduction in volume of FFP administered (0.3 vs. 0.6 units, p < 0.001). Use of TEG was not observed to significantly decrease postoperative blood product usage or mortality. The median length of hospital stay was reduced by 1 day after TEG guided transfusion was implemented (nine days vs. eight days, p = 0.01). Conclusions. Use of TEG-directed transfusion of blood products following CPB appears to decrease the need for intraoperative transfusions, but the effect on clinical outcomes has yet to be clearly determined.

Small bowel perforation with iliac artery prosthesis stump

Aim: In this case we report an unusual complication after retroperitoneal formation of an iliac artery prosthesis-stump – a bowel perforation and sepsis. Case report: During the open urology surgery a right external iliac artery was iatrogenic injured and iliofemoral bypass grafting was performed. Eight months thereafter, due to an inguinal site graft infection and graft occlusion, the distal part of the prosthesis was transacted and removed, and the proximal, retroperitoneal part, was closed and over sewn in the zone without any sign of infection present. This prosthesis-stump caused a very unusual complication – a small bowel perforation three months thereafter. Conclusion: The whole retroperitoneal graft should always be removed with no stump formation to avoid this complication.

Intraoperative Assessment of Coronary Resistances: A New Quality Marker and Potential Tool to Predict Early Graft Failure after Coronary Artery Bypass Grafting?

Intraoperative assessment of graft patency is pivotal for successful coronary revascularization. In the present study we aimed to propose a new, easy to perform tool to assess anastomotic quality intraoperatively, and to investigate its potential reliability in predicting early graft failure. Intraoperative graft flowmetry of 63 consecutive patients undergoing CABG were prospectively collected. Transit time flowmetry and its derivatives were recorded. Coronary resistances were calculated according to Hagen–Poiseuille equation both during cardioplegic arrest and after withdrawal from cardiopulmonary bypass. Angiographic evidence of graft occlusion at follow-up was cross-checked with intraoperative recordings. After a mean follow-up of 10.4 ± 6.0 months, 22 grafts were studied, and occlusion was documented in five (22.7%). Occluded grafts showed lower flows and higher resistances recorded during aortic cross-clamping. Coronary resistances, recorded during aortic cross-clamping, greater than 2.0 mmHg/mL/min, showed a sensitivity of 80% and a specificity of 100% to predict graft failure. We propose the routine recording of coronary resistances during aortic cross-clamping as an additional tool to overcome the acknowledged limitation of TTF to predict graft occlusion at 1 year.

Novel use of a mechanical suction thrombectomy system for interposition graft occlusion in complex congenital heart disease

Complete thrombosis of a pulmonary artery interposition graft in an adolescent with complex repaired CHD was treated successfully with a combination of a novel mechanical thrombectomy system, stent implantation, and thrombolysis. This thrombectomy system used a flexible catheter with a built-in mechanism to attenuate blood loss, while providing effective recanalisation of a foreign graft.

The role of venous pressure variability during hemodialysis in the prediction of impending arteriovenous graft occlusion

Background: Elevated venous pressure during hemodialysis (VPHD) is associated with arteriovenous graft (AVG) stenosis. This study investigated the role of VPHD variations in the prediction of impending AVG occlusion. Methods: Data were retrieved from 118 operations to treat AVG occlusion (occlusion group) and 149 operations to treat significant AVG stenosis (stenosis group). In addition to analyzing the VPHD values for the three hemodialysis (HD) sessions prior to the intervention, VPHD values were normalized to mean blood pressure (MBP), blood flow rate (BFR), BFR × MBP, and BFR2 × MBP to yield ratios for analysis. The coefficient of variation (CV) was used to measure relative variations. Results: The within-group comparisons for both groups revealed no significant differences in the VPHD mean and CV values among the three HD sessions prior to intervention. However, the CVs for VPHD/MBP, VPHD/(BFR × MBP), and VPHD/(BFR2 × MBP) exhibited significant elevation in the occlusion group during the last HD session prior to intervention compared with both the penultimate and antepenultimate within-group HD data ( p < 0.05). In the receiver operating characteristic curve analysis, the CV for VPHD/(BFR2 × MBP) was the only parameter able to discriminate between the last and the penultimate HD outcomes ( p < 0.001). According to a multivariate analysis, after controlling for covariates, CV for VPHD/(BFR2 × MBP) >8.76% was associated with a higher risk of AVG thrombosis (odds ratio: 3.17, p < 0.001). Conclusions: Increasing the variation in VPHD/(BFR2 × MBP) may increase the probability of AVG occlusion.

Stent Graft Placement by Pseudoaneurysm of the Hepatic Arteries: Efficacy and Patency Rate in Follow-up

Purpose To investigate efficacy and patency status of stent graft implantation in the treatment of hepatic artery pseudoaneurysm. Materials and Methods A retrospective analysis of patients who had undergone endovascular treatment of hepatic artery pseudoaneurysms between 2011 and 2020 was performed. Medical records were examined to obtain patients’ surgical histories and to screen for active bleeding. Angiographic data on vascular access, target vessel, material used and technical success, defined as the exclusion of the pseudoaneurysm by means of a stent graft with sufficient control of bleeding, were collected. Vessel patency at follow-up CT was analyzed and classified as short-term (< 6 weeks), mid-term (between 6 weeks and 1 year), and long-term patency (> 1 year). In case of stent occlusion, collateralization and signs of hepatic hypoperfusion were examined. Results In total, 30 patients were included and of these, 25 and 5 had undergone stent graft implantation and coiling, respectively. In patients with implanted stent grafts, technical success was achieved in 23/25 patients (92%). Follow-up CT scans were available in 16 patients, showing stent graft patency in 9/16 patients (56%). Short-term, mid-term, and long-term short-term stent patency was found in 81% (13/16), 40% (4/10), and 50% (2/4). In patients with stent graft occlusion, 86% (6/7) exhibited maintenance of arterial liver perfusion via collaterals and 14% (1/7) exhibited liver abscess during follow-up. Conclusion Stent graft provides an effective treatment for hepatic artery pseudoaneurysms. Even though patency rates decreased as a function of time, stent occlusion was mainly asymptomatic due to sufficient collateralization.

No-Touch Versus Conventional Vein Harvesting Techniques at 12 Months After Coronary Artery Bypass Grafting Surgery: Multicenter Randomized, Controlled Trial

Background: Vein graft occlusion is deemed a major challenge in coronary artery bypass grafting. Previous studies implied that the no-touch technique for vein graft harvesting could reduce occlusion rate compared with the conventional approach; however, evidence on the clinical benefit and generalizability of the no-touch technique is scare. Methods: From April 2017 to June 2019, we randomly assigned 2655 patients undergoing coronary artery bypass grafting at 7 hospitals in a 1:1 ratio to receive no-touch technique or conventional approach for vein harvesting. The primary outcome was vein graft occlusion on computed tomography angiography at 3 months and the secondary outcomes included 12-month vein graft occlusion, recurrence of angina, and major adverse cardiac and cerebrovascular events. The generalized estimate equation model was used to account for the cluster effect of grafts from the same patient. Results: During the follow-up, 2533 (96.0%) participants received computed tomography angiography at 3 months after coronary artery bypass grafting and 2434 (92.2%) received it at 12 months. The no-touch group had significantly lower rates of vein graft occlusion than the conventional group both at 3 months (2.8% versus 4.8%; odds ratio, 0.57 [95% CI, 0.41–0.80]; P <0.001) and 12 months (3.7% versus 6.5%; odds ratio, 0.56 [95% CI, 0.41–0.76]; P <0.001). Recurrence of angina was also less common in the no-touch group at 12 months (2.3% versus 4.1%; odds ratio, 0.55 [95% CI, 0.35–0.85]; P <0.01). Rates of major adverse cardiac and cerebrovascular events were of no significant difference between the 2 groups. The no-touch technique was associated with higher rates of leg wound surgical interventions at 3-month follow-up (10.3% versus 4.3%; odds ratio, 2.55 [95% CI, 1.85–3.52]; P <0.001). Conclusions: Compared with the conventional vein harvesting approach in coronary artery bypass grafting, the no-touch technique significantly reduced the risk of vein graft occlusion and improved patient prognosis. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03126409.

SP5.2.4 Stent-graft endobypass for non-infected femoral pseudoaneurysms in high-risk surgical patients: acceptable short-to-mid-term results

Aim Stent-grafts are finding a place in the treatment of femoral pseudoaneurysms (FpsAs), having been described in the treatment of infected pseudoaneurysms. We present the results of endovascular treatment of non-infected FpsAs using stent-grafts. Methods Case series of patients who underwent stent-graft coverage of FpsAs from January 2016 to December 2020. Stent-graft fractures, occlusions and reinterventions, length of stay (LOS) and 30-day mortality were assessed. Results 11 patients (mean age 75±10.3 years, 7 males; all ASA 3 or 4) underwent stent-graft coverage of FpsAs. Original procedures linked to the formation of FpsA were iliofemoral bypass (n = 3), femorofemoral crossover (n = 3), percutaneous coronary interventions (n = 2), aortobifemoral bypass (n = 1), endovascular aneurysm repair (n = 1) and femoral endarterectomy (n = 1). 3 patients had previous open FpsA repair. Technical success of deployment was 100%. Stent-grafts used included Viabahn Endoprosthesis (WL Gore & Associates, Flagstaff USA; n = 8), Viabahn VBX (WL Gore & Associates; n = 1) and BeGraft (Bentley InnoMed GmbH, Hechingen, Germany; n = 2). All patients were maintained on either antiplatelets or anticoagulant. 10 patients were available for analysis (1 lost to follow-up); radiological follow-up included initial computed tomography angiography and later combined duplex ultrasonography/plain radiography. Median LOS was 4 days (IQR 4). 30-day mortality was 0%. Median survival was 12 months (IQR 17). There was one stent-graft occlusion requiring thrombectomy but no fractures were observed in this series. Conclusions This small series suggests that there may be a role for stent-grafts in treatment of FpsAs in carefully selected patients. Given lack of data on long-term outcomes, continued surveillance is recommended.

Dialysis access graft occlusion with contrast and ultrasound guided thrombin injection for intractable arm edema and pseudoaneurysm

We present the case of a patient with a brachio-basilic graft forearm loop with intractable edema and thrombosed central veins. She showed up with an important edema after some effort and a previously thrombosed pseudoaneurysm with significant growth. She refused angioplasty treatment for central veins, the graft had not been used for dialysis during the last year, so that arteriovenous graft (AVG) ligation was considered. Due to local conditions thrombin percutaneous embolization was performed to avoid possible complications of a conventional surgery approach. AVG occlusion was done in 10 min by fluoroscopy and ultrasound guidance. In 24 h the patient was significantly better and after 1 week she had no edema at all. There were no complications and no recanalization was observed after 3 months. Percutaneous thrombin embolization is a safe and effective technique for AVG occlusion in case of intractable arm edema with central vein thrombosis, and most likely to be considered in other situations where arteriovenous graft or fistula ligature is needed.

Increased patency with comparable mortality and revascularization risk: Is the case for no-touch vein harvesting open and shut?

Since the introduction of the saphenous vein graft (SVG) for coronary artery bypass grafting (CABG) in 19621, the SVG has remained the most commonly used conduit to the non-LAD territories for more than half a century. However, several issues surrounding the use of SVGs, including higher graft occlusion rates and wound complications from the harvesting process, have been identified in clinical practice. As such, significant interest has been dedicated towards developing harvesting techniques that minimize the risk of these acute and late complications. In this issue of the Journal of Cardiac Surgery, Yokoyama and colleagues compared the impact of open vein harvesting (OVH), endoscopic vein harvesting (EVH) and no-touch vein harvesting (NT) on all-cause mortality, revascularization and graft failure, using a network meta-analysis based on randomized controlled trials and propensity-score matched studies. The results showed that the risk of graft failure was approximately halved amongst patients receiving NT compared with EVH and OVH; importantly, though, NT was not associated with lower all-cause mortality or revascularization risk. To further examine whether the use of NT grafts endow patients with better long-term clinical outcomes, such as mortality, myocardial infarction, and revascularization rates, a large-scaled randomized controlled trial or a patient-level combined meta-analysis is required.