Drug-eluting versus bare metal stent in treatment of patients with saphenous vein graft disease: A meta-analysis of randomized controlled trials

Saphenous Vein Vasa Vasorum as a Potential Target for Perivascular Fat-Derived Factors

Perivascular adipose tissue (PVAT) is a source of factors affecting vasomotor tone with the potential to play a role in the performance of saphenous vein (SV) bypass grafts. As these factors have been described as having constrictor or relaxant effects, they may be considered either beneficial or detrimental. The close proximity of PVAT to the adventitia provides an environment whereby adipose tissue-derived factors may affect the vasa vasorum, a microvascular network providing the vessel wall with oxygen and nutrients. Since medial ischaemia promotes aspects of graft occlusion the involvement of the PVAT/vasa vasorum axis in vein graft patency should be considered.

Outcomes of primary percutaneous cardiac intervention for ST elevation myocardial infarction with a saphenous vein graft culprit

BACKGROUND

Patients treated with primary percutaneous coronary intervention (pPCI) for ST elevation myocardial infarction (STEMI) who have a history of coronary artery bypass grafting (CABG) are at high risk of adverse cardiovascular outcomes. Data on the risk of a saphenous vein graft (SVG)-infarct-related artery (IRA) compared to other culprit vessels are sparse.

METHODS

The study was based on a prospectively collected registry of 2,405 consecutive patients with STEMI attending a tertiary medical center in 2001-2017. Patients with an SVG-IRA (n = 172) were compared with patients with native vessel disease (n = 2,333) for mortality and major adverse cardiac events (MACE), which included death, myocardial infarction (MI), target vessel revascularization (TVR), and coronary artery bypass surgery (CABG) at 1 month and 3 years.

RESULTS

The SVG-IRA group was significantly older than the native vessel group (p = .05), with no between-group differences in rates of male patients (76 vs. 82%, p = .59), diabetes (24.2 vs. 26.2%, p = .73), and renal failure (18.8 vs. 9.2%, p = .25). Mortality was higher in the SVG-IRA group at 1 month (13.9 vs. 2.5%, p < .01) and 3 years (23.9 vs. 7.4%, p < .01). At 3 years, SVG-IRA was associated with the highest rates of MACE (55.6%), compared with native vessel disease. After correction for confounders, SVG-IRA remained an independent risk factor for MACE both at 1 month (HR-2.08, 95%CI 1.72-3.11, p < .01) and 3 years (HR-2.01, 95%CI 1.28-3.09, p < .01).

CONCLUSION

Among patients treated with pPCI for STEMI, outcomes are worse when the culprit is an SVG.

Drug-Eluting Versus Bare Metal Stents in Saphenous Vein Graft Intervention: An Updated Comprehensive Meta-Analysis of Randomized Trials

BACKGROUND

Drug eluting stents (DES) are preferred over bare metal stents (BMS) for native coronary artery revascularization unless contraindicated. However, the preferred stent choice for saphenous venous graft (SVG) percutaneous coronary interventions (PCI) is unclear due to conflicting results.

METHODS

PubMed, Clinical trials registry and the Cochrane Center Register of Controlled Trials were searched through June 2018. Seven studies (n = 1639) comparing DES versus BMS in SVG-PCI were included. Endpoints were major adverse cardiac events (MACE), cardiovascular mortality, all-cause mortality, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), in-stent thrombosis, binary in-stent restenosis, and late lumen loss (LLL).

RESULTS

Overall, during a mean follow up of 32.1 months, there was no significant difference in the risk of MACE, cardiovascular mortality, all-cause mortality, MI, stent thrombosis, TVR and TLR between DES and BMS. However, short-term follow up (mean 11 months) showed lower rate of MACE (OR 0.66 [0.51, 0.85]; p = 0.002), TVR (OR 0.47 [0.23, 0.97]; p = 0.04) and binary in-stent restenosis (OR 0.14 [0.06, 0.37]; p < 0.0001) in DES as compared with BMS. This benefit was lost on long-term follow up with a mean follow up 35.5 months.

CONCLUSION

In this meta-analysis of SVG-PCI, DES use was associated with similar MACE, cardiovascular mortality, all-cause mortality, MI, in-stent thrombosis, TVR and TLR compared with BMS during long-term follow up. There was high incidence of MACE noted in both DES and BMS suggesting a need for exploring novel strategies to treat SVG disease to improve clinical outcomes.