Saphenous vein graft harvesting and patency: No-touch harvesting is the answer

Long-term results of percutaneous coronary intervention in no-touch vein grafts are significantly better than in conventional vein grafts

INTRODUCTION

Conventional vein grafts have a high risk of thrombosis and early atherosclerosis. Percutaneous coronary intervention (PCI) in conventional vein grafts is associated with a higher incidence of late adverse cardiac events. The aim of this study was to evaluate the long-term results after PCI in saphenous vein grafts (SVG) harvested with the no-touch technique compared to the conventional technique.

METHODS

This was a single-center, retrospective, cohort study, based on data from the Swedeheart register. The inclusion criterion was individuals who underwent CABG using different vein graft techniques between January 1992 and July 2020, and who required a PCI in SVGs between January 2006 and July 2020. The primary end point was long-term in-stent restenosis. The secondary endpoints were long-term major adverse cardiac events (MACE) and 1-year re-hospitalization rates. The associations between the graft types and the endpoints were evaluated using the Fine and Gray competing-risk regression analysis.

RESULTS

The study included 346 individuals (67 no-touch, 279 conventional). The mean clinical follow-up time was 6.4 years with a standard deviation of 3.7 years. The long-term in-stent restenosis rate for the no-touch grafts was 3.2% compared to 18.7% for the conventional grafts (p < .01), with a subdistribution hazard ratio (SHR) of 0.16 (p = .010). The long-term MACE rate was 27.0% in the no-touch group and 48.3% in the conventional group (p < .01) with a SHR of 0.53 (p = .017). The short-term results were similar in both groups.

CONCLUSIONS

Percutaneous coronary intervention in a no-touch vein graft was associated with statistically significantly fewer in-stent restenoses and MACE at long-term follow-up compared to a conventional SVG.

The Etiology and Molecular Mechanism Underlying Smooth Muscle Phenotype Switching in Intimal Hyperplasia of Vein Graft and the Regulatory Role of microRNAs

Mounting evidence suggests that the phenotypic transformation of venous smooth muscle cells (SMCs) from differentiated (contractile) to dedifferentiated (proliferative and migratory) phenotypes causes excessive proliferation and further migration to the intima leading to intimal hyperplasia, which represents one of the key pathophysiological mechanisms of vein graft restenosis. In recent years, numerous miRNAs have been identified as specific phenotypic regulators of vascular SMCs (VSMCs), which play a vital role in intimal hyperplasia in vein grafts. The review sought to provide a comprehensive overview of the etiology of intimal hyperplasia, factors affecting the phenotypic transformation of VSMCs in vein graft, and molecular mechanisms of miRNAs involved in SMCs phenotypic modulation in intimal hyperplasia of vein graft reported in recent years.

Percutaneous coronary intervention in saphenous vein grafts after coronary artery bypass grafting: a systematic review and meta-analysis

To investigate the results of percutaneous coronary intervention (PCI) in saphenous vein grafts after coronary artery bypass grafting (CABG). Design. MEDLINE, Embase, and the Cochrane library were searched for relevant articles published between 1 January 2000 and 29 February 2020. The PICO (population, intervention, comparison, outcome) model was applied in constructing the clinical question. Two independent researchers performed the literature search. Thirty-six articles were identified and subjected to a quality assessment. The primary outcomes of the meta-analysis were long-term in-stent restenosis and long-term major adverse cardiac events (MACE). Results. In-stent restenosis was 9.4% (95% CI: 4.2-14.7%) and MACE was 35.3% (95% CI: 27-43.7%) at mean time 2.7 ± 1.0 years. The secondary outcomes were the unsuccessful PCI rate (7.7%; 95% CI: 2.9-12.5%), 30-day MACE (4.3%; 95% CI: 2.5-6.1%), and 1-year MACE (15.5%; 95% CI: 11.7-19.3%). The use of drug-eluting stents resulted in better outcomes at least in term of in-stent restenosis, while the benefit of using embolic protection devices was questionable. Conclusions. PCI of a stenosed or occluded saphenous vein graft is a challenge for interventional cardiologists, and is still associated with relatively high rates of restenosis, MACE, and procedural failure. All efforts to enhance the results are warranted, including improved quality of the venous grafts used during CABG.

The radial artery in coronary surgery, 2018

It is now 25 years since the radial artery (RA) was reintroduced in coronary surgery. It has evolved into being a significant coronary artery bypass conduit and ranks third in usage after the internal thoracic artery (ITA) and saphenous vein grafts (SVG). Its advantages are that it can be readily and efficiently harvested, is of good length and appropriate size for coronary artery bypass graft (CABG) surgery, is robust and easy to handle, and remains free of atheroma, and there is minimal wound morbidity. The RA must be used judiciously with attention to spasm prophylaxis because of its muscular wall, and by avoiding competitive flow. Its patency is equivalent to the ITAs when placed to similar coronary territories and under similar conditions (stenosis, size, quality) and RA patencies are always superior to those of SVG in both observational and randomized studies-88-90% versus 50-60% at 10 years, and 80-87% versus 25-40% at 20 years. Its use and excellent patencies result in survival results equivalent to bilateral internal thoracic artery (BITA) grafting and always superior to left internal thoracic artery (LITA) +SVG. Typical radial artery multiarterial bypass grafting (RA-MABG) 10-year survivals are 80-90% versus 70-80% for LITA-SVG. In general, for every 100 patients undergoing CABG, 10 more patients will be alive at 10 years post-operatively. The RA also is important in achieving total arterial revascularization, and several reports indicate a further survival advantage for patients having three arterial grafts over two. The RAs are especially useful in diabetic, morbidly obese patients, those with conduit shortage, and leg pathology, and in coronary reoperations. Although the RA has equivalent patencies to the right internal thoracic artery (RITA), it is much more versatile. RAs that have been instrumented by angiography or percutaneous coronary intervention should be avoided. The radial artery has proved to be an excellent arterial conduit, is equivalent to but more versatile than the RITA, and is always superior to SVG. Its use should be part of every coronary surgeon's skill set.