Hybrid coronary revascularization: the future of coronary artery bypass surgery or an unfulfilled promise?

Late clinical outcomes of myocardial hybrid revascularization versus coronary artery bypass grafting for complex triple-vessel disease: Long-term follow-up of the randomized MERGING clinical trial

OBJECTIVES

This article aimed to compare the outcomes after hybrid revascularization with conventional coronary artery bypass grafting (CABG) surgery.

BACKGROUND

The concept of hybrid coronary revascularization combines the advantages of CABG and percutaneous coronary intervention to improve the treatment of patients with complex multivessel disease.

METHODS

The Myocardial hybrid revascularization versus coronary artERy bypass GraftING for complex triple-vessel disease-MERGING study is a pilot randomized trial that allocated 60 patients with complex triple-vessel disease to treatment with hybrid revascularization or conventional CABG (2:1 ratio). The primary outcome was the composite of all-cause death, myocardial infarction, stroke, or unplanned repeat revascularization at 2 years.

RESULTS

Clinical and anatomical characteristics were similar between groups. After a mean follow-up of 802 ± 500 days, the primary endpoint rate was 19.3% in the hybrid arm and 5.9% in the CABG arm (p = NS). The incidence of unplanned revascularization increased over time in both groups, reaching 14.5 versus 5.9% in the hybrid and in the CABG groups, respectively (p = .4). Of note, in the hybrid group, there were no reinterventions driven by the occurrence of stent restenosis.

CONCLUSIONS

Hybrid myocardial was feasible but associated with increasing rates of major adverse cardiovascular events during 2 years of clinical follow-up, while the control group treated with conventional surgery presented with low rates of complications during the same period. In conclusion, before more definitive data arise, hybrid revascularization should be applied with careful attention in practice, following a selective case-by-case indication.

Hybrid Revascularization: A Review

Hybrid coronary revascularization (HCR) combines surgical bypass with percutaneous coronary intervention (PCI) performed either during the same procedure or in a staged approach within 60 days. Coronary artery bypass grafting using the left internal mammary artery (LIMA) has shown excellent long-term patency with improved patient survival. It remains the gold standard treatment for the majority of patients with multivessel coronary artery disease. However, saphenous vein grafts have poor long-term patency. Advances in stent technology have resulted in reduced rates of thrombosis and restenosis, making PCI a viable alternative to coronary surgery in selected patients. HCR is attractive as a less invasive method of coronary revascularization which preserves the benefits of the LIMA performed with less invasive surgical techniques with the efficacy of newer generation stents.

The curative effect of synthetic treatment for refractory acute myocardial infarction

Background

This study aims to investigate the curative effect of synthetic treatment for refractory acute myocardial infarction (AMI).

Methods

A total of 76 patients with coronary AMI accompanied by shock, who were treated with combined therapy from August 1999 to April 2017, were included into this study. Sixty patients received emergency percutaneous coronary intervention (PCI). Among these patients, 39 patients received intra-aortic balloon counterpulsation (IABP), eight patients had failed PCI underwent emergency off-pump coronary artery bypass (E-OPCAB), and eight patients were treated by hybrid cardiac surgery.

Results

All patients were successfully rescued. However, two patients died afterward due to postoperative complications.

Conclusions

For AMI patients complicated with shock, especially when emergency PCI fails or is difficult to perform, PCI + IABP, emergency E-OPCAB and hybrid cardiac surgery should be carried out, in order to achieve a good outcome and improve the success rate of rescue for this group of patients.

Keywords

Acute myocardial infarction (AMI); emergency percutaneous coronary intervention (PCI); intra-aortic balloon counterpulsation (IABP); emergency off-pump coronary artery bypass (E-OPCAB); hybrid cardiac surgery.

Cardiovascular tissue engineering: where we come from and where are we now?

Tissue engineering was introduced by Vacanti and Langer in the 80’s, exploring the potential of this new technology starting with the well-known “human ear on the mouse back”. The goal is to create a substitute which supplies an individual therapy for patients with regeneration, remodeling and growth potential. The growth potential of these subjects is of special interest in congenital cardiac surgery, avoiding repeated interventions and surgery. Initial applications of tissue engineered created substitutes were relatively simple cardiovascular grafts seeded initially by end-differentiated autologous endothelial cells. Important data were collected from these initial clinical autologous endothelial cell seeded grafts in peripheral and coronary vessel disease. After these initial successfully implantation bone marrow cell were used to seed patches and pulmonary conduits were implanted in patients. Driven by the positive results of tissue engineered material implanted under low pressure circumstances, first tissue engineered patches were implanted in the systemic circulation followed by the implantation of tissue engineered aortic heart valves. Tissue engineering is an extreme dynamic technology with continuously modifications and improvements to optimize clinical products. New technologies are unified and so this has also be done with tissue engineering and new application features, so called transcatheter valve intervention. First studies are initiated to apply tissue engineered heart valves with this new transcatheter delivery system less invasive. Simultaneously studies have been started on tissue engineering of so-called whole organs since organ transplantation is restricted due to donor shortage and tissue engineering could overcome this problem. Initial studies of whole heart engineering in the rat model are promising and larger size models are initiated.