PCI for Left Main CAD: Meta-analysis Finds No Increased Risk of Mortality

The latest study to take a crack at the question of increased mortality according to revascularization choice in left main coronary artery disease—this one a meta-analysis looking at long-term data—has found no increased risk of mortality with PCI compared with CABG.

The study, published online as a research letter in the American Heart Journal on June 7, 2020, includes the EXCEL and NOBLE studies, as well as PRECOMBAT and SYNTAX, and based on these four studies, all with more than 5-years follow-up, the risk of all-cause mortality in 4,394 patients with left main CAD was no different between those treated with PCI versus surgery (HR 1.11; 95% CI 0.91-1.35). The risk of cardiovascular death also was similar between the two treatment arms (HR 1.13; 95% CI 0.88-1.44), as was the risk of stroke (HR 0.81; 95% CI 0.42-1.53).

There was, however, a significantly higher risk of the need for repeat revascularization with PCI (HR 1.80; 95% CI 1.52-2.13).

“The issue of PCI versus CABG for left main disease continues to be an ongoing debate,” lead investigator Sripal Bangalore, MD (NYU Langone Medical Center, New York, NY), told TCTMD. “There’s been a lot of hype, at least a lot of hype on social media, about whether CABG is superior [to PCI] when focusing on the EXCEL trial. If you look at the totality of the data, we have shown there isn’t a lot of difference between PCI and CABG.”

People need to recognize there are shades of gray and we need to convey those results to the patients. Sripal Bangalore

When making decisions, Bangalore stressed the importance of the heart team, which includes surgeons and interventionalists, to help the patient select the best revascularization strategy for them.

These new data add to a field rife with controversy since the 5-year results of EXCEL were presented and published in 2019. In that study, the absolute risk of all-cause mortality at 5 years was 3.1% higher with PCI compared with surgery, a significant difference, and there have been accusations from one of the surgeons involved in the trial that the EXCEL researchers downplayed the mortality finding. There was no increased risk of death at 5 years in the NOBLE study, although in this trial the risk of nonprocedural MI was significantly increased in the PCI arm. There was no difference in mortality seen in SYNTAX or PRECOMBAT at 10 years.   

As a result of the EXCEL controversy, which also included criticisms the researchers failed to publish MI data adjudicated using the universal definition and downplayed concerns from the data and safety monitoring board, the European Association for Cardio-Thoracic Surgery withdrew their support from the European Society of Cardiology guidelines’ section on left main disease.

Bangalore said the controversy and vitriol over the optimal strategy for revascularization of left main CAD has been unfortunate, particularly given the collegiality of the heart team approach to patient care. “What is happening is that people are looking at all these results as black and white,” he said. “PCI is better, or CABG is better. People need to recognize there are shades of gray and we need to convey those results to the patients.” Based on their analysis and others, Bangalore said the data do not suggest there is a significant benefit of CABG in follow-up beyond 5 years.  

Just last week, a new Bayesian analysis took a look at the EXCEL mortality question. With respect to the controversial all-cause mortality finding, James Brophy, MD, PhD (McGill University Health Center, Montreal, Canada), found that when taking other studies into consideration to inform the mortality endpoint, including NOBLE, PRECOMBAT, and SYNTAX, the difference in death was 0.9% higher with PCI. Based on that, the probability of more deaths with PCI was 85% and there was a 47% probability of there being at least one more death per 100 patients treated, he reported.

To TCTMD, Bangalore said the Bayesian results actually support their current findings. When placing EXCEL in context with the other studies, the posterior probability of the 1% survival benefit with CABG surgery was just 47%. “In other words, it’s the flip of a coin,” he said. “And that’s exactly what we showed in our study—there was no difference in survival between PCI and CABG.”