Hybrid Coronary Revascularization at 5 Years: Similar Outcomes to CABG

Compared with conventional CABG, hybrid coronary revascularization (HCR) is associated with similar rates of all-cause mortality and adverse events at 5 years among patients with multivessel disease, according to new randomized data.

“Our study shows that HCR is a promising coronary revascularization strategy in selected patients with multivessel coronary artery disease,” write lead study author Mateusz Tajstra, MD (Silesian Center for Heart Diseases, Zabrze, Poland), and colleagues. “This warrants further validation in multicenter, adequately powered randomized studies to definitively assess the absolute benefits and risks of HCR.”

HCR is currently performed in less than 10% of coronary bypass surgeries in the United States, according to Vinod Thourani, MD (MedStar Heart & Vascular Institute, Washington, DC), who was not involved in the study. Though this trial was small, he told TCTMD, it highlights the promise of a procedure that “potentially provides the best of both worlds” with minimally invasive grafting of the left internal mammary artery to the left anterior descending artery, followed by the implantation of drug-eluting stents elsewhere in the coronary tree.

One-year findings from the POL-MIDES (HYBRID) study, which showed safety and feasibility of the procedure among 200 patients with obstructed LAD and a critical lesion (> 70%) in at least one other major epicardial vessel and were candidates for both procedures, were published in November 2014 in JACC: Cardiovascular Interventions.

The 5-year results, published online last week ahead of print in JACC: Cardiovascular Interventions, showed similar all-cause mortality among the 191 patients with data in the HCR and CABG arms (primary endpoint; 6.4% vs 9.2%; P = 0.69) as well as similar rates of MI (4.3% vs 7.2%; P = 0.30), repeat revascularization (37.2% vs 45.4%; P = 0.38), stroke (2.1% vs 4.1%; P = 0.35), and MACCE (45.2% vs 45.4%; P = 0.39).

There remained no differences in any outcomes when patients were stratified by both EuroSCORE and SYNTAX score tertiles.

‘Very Welcome’ Data

These results are “reassuring,” said John Douglas, Jr, MD (Emory University Medical Center, Atlanta, GA), who was not involved in the study. “There was concern that if you do a minimally invasive surgery, it's technically more demanding and the results may not be as good, but there were no statistical differences between the outcomes of these two groups,” he told TCTMD.

However, “the trends are all favoring better outcomes with the hybrid group,” Douglas said, acknowledging that the study was likely underpowered. “If you look for instance at the mortality, . . . it was 40% higher in the bypass group—not statistically different—but it was definitely high in the patients who had bypass surgery.”

This study highlights how important it is for us to talk to our patients through a multidisciplinary or heart team, where we can really give the patient options depending on their comorbidities and their age and their longevity. Vinod Thourani

In an accompanying editorial, Adrian Messerli, MD, and Naoki Misumida, MD (University of Kentucky, Lexington), write that “while these 5-year data are very welcome, the overall published HCR experience remains small and mostly hypothesis-generating. To be fair, all available data suggest HCR is feasible and safe in skilled hands, with 1- and 5-year outcomes noninferior to conventional CABG in low- to intermediate-risk patients with multivessel CAD.”

Besides the need for more randomized trial data, the biggest hurdle to the procedure’s increased prevalence is that “it requires surgical expertise,” Douglas said. “Not every surgeon can do [it] and not every surgeon is even interested in trying. Many surgeons have learned how to do a good open operation and feel comfortable with that, and simply don't want to go through the learning curve to become proficient in a minimally invasive strategy.”

Messerli and Misumida also argue that “the utilization of HCR remains low, in part due to a number of clinical unknowns, but also due to practical limitations: logistics (simultaneous in hybrid operation room versus two-stage); specific expertise, cooperation and collaboration of surgical and interventional teams; risk of perioperative bleeding with the use of aggressive antiplatelet and antithrombotic therapy; insecurity about left main cohort outcomes; and uncertain cost effectiveness.”

Adoption of HCR will remain “modest” until large randomized trials “can prove superiority to conventional CABG in clinical outcomes such as significant morbidity or stroke reduction,” they add.

Looking Ahead

The US National Institutes of Health-sponsored HYBRID trial of more than 2,000 patients being randomized to HCR or PCI is currently enrolling and should give some valuable insight into the efficacy of HCR in patients with multivessel disease, Thourani said.

In addition, he said that he would like to see studies incorporate “more contemporary surgical options” like multiple arterial grafting or saphenous vein graft scaffolding and potentially include angiographic follow-up for longer than 1 year.

But the most important takeaway for the future success of HCR, Thourani stressed, is that it should be performed with a heart team approach similar to what is currently done with TAVR.

“Surgeons and interventional cardiologists should see the patients potentially together so that you provide the patient with the best options, which may be percutaneous coronary intervention alone, it could be a hybrid revascularization, or it could be open surgery with more arterial grafting,” he said. “This study highlights how important it is for us to talk to our patients through a multidisciplinary or heart team, where we can really give the patient options depending on their comorbidities and their age and their longevity.”