By Jeffrey Zimmet, MD, PhD
Associate Professor of Medicine, University of California, San Francisco; Director, Cardiac Catheterization Laboratory San Francisco VA Medical Center
SYNOPSIS: In this study of data from the REVASC TAVI registry, completeness of myocardial revascularization did not significantly affect the risk of all-cause mortality or the combined endpoint of death, stroke, myocardial infarction, or heart failure hospitalization at two years.
SOURCE: Costa G, Pilgrim T, Amat Santos IJ, et al. Management of myocardial revascularization in patients with stable coronary artery disease undergoing transcatheter aortic valve implantation. Circ Cardiovasc Interv 2022;15:e012417.
Most patients for whom transcatheter aortic valve replacement (TAVR) is contemplated undergo screening for coronary artery disease, most often by invasive coronary angiography or CT. Many of these patients present with coincident obstructive coronary disease by virtue of advanced age and multiple risk factors. A relatively small fraction of these may be living with disease that affects the hemodynamics and safety of the TAVR procedure. The right course for most prospective TAVR patients with significant coronary artery disease (CAD) remains unknown. In many centers, the default approach has been to offer patients percutaneous coronary intervention (PCI) of all addressable lesions. However, supporting data are lacking.
The authors of Management of Myocardial Revascularization in Patients Undergoing Transcatheter Aortic Valve Implantation With Coronary Artery Disease (REVASC-TAVI) collected data on patients found to be living with significant, untreated CAD at the time of pre-TAVR work-up. Thirty multinational centers have contributed patient-level data, resulting in enrollment of 2,025 patients for whom complete follow-up data are available. Among these, complete revascularization was achieved in nearly 65%. Investigators sought to compare outcomes in patients for whom complete revascularization was achieved with those for whom it was not. Using propensity score matching, the authors identified 675 pairs of patients as either complete revascularization or incomplete revascularization.
The average age of enrolled patients was 82.6 years, 40.7% were women, and the average Society of Thoracic Surgeons predicted risk of mortality was 4.8%. Patients in the incomplete revascularization group were more likely than those in the complete group to have multivessel and three-vessel disease (64.4% vs. 33.9%; P < 0.01). However, percentages of patients with left main disease, proximal left anterior descending disease, and proximal segment disease in other vessels were similar between groups. PCI was performed in all patients in the complete revascularization group and in 43.7% of the incomplete revascularization group. Among patients who underwent PCI, revascularization was staged (primarily before the valve procedure) in 72.1% and was performed concomitantly with TAVR in 26.3%.
At two years, all-cause mortality did not differ significantly between groups (21.6% vs. 18.2%; P = 0.38). Likewise, the co-primary endpoint of a composite of death, stroke, myocardial infarction, or rehospitalization for heart failure at two years also was not significantly different (29% vs. 27.1%; HR, 0.97; 95% CI, 0.76-1.24). Subgroup analyses revealed similar outcomes among patients younger than age 75 years and among those presenting with angina and left ventricular dysfunction.
In this registry study of primarily elderly, intermediate-risk TAVR patients with CAD, the authors concluded the completeness of coronary revascularization did not affect the two-year risk of all-cause death or of a composite of cardiovascular outcomes. They posited the data support taking a conservative approach to stable coronary disease in the average TAVR population.
COMMENTARY
In patients undergoing surgical AVR (SAVR), coronary artery bypass grafting at the time of SAVR has been the standard approach. In many ways, the surgical approach to coincident coronary disease has been carried over to TAVR, despite the differences in the risk profiles of the valve procedures themselves and the fact most TAVR cases can be completed safely without coronary revascularization.
There is no particular reason to believe stable CAD in elderly patients with aortic stenosis (AS) should behave any differently regarding revascularization than patients without valvular heart disease. In general, the treatment of stable coronary disease in these patients should follow the current evidence. Costa et al have added evidence showing the completeness of revascularization does not reduce the risk of death or adverse cardiac events out to two years.
Revascularization is beneficial when treating angina — but only among patients with angina. When we systematically screen a subset of elderly patients with AS by invasive coronary angiography, we should be honest about what we are trying to achieve with revascularization. In patients with clear angina and a culprit vessel that may be treated with an acceptable risk profile, PCI may be offered as a reasonable adjunct to medical therapy.
Experienced clinicians will recognize the existence of a subset of patients with AS and severe CAD where the origin of symptoms is unclear, as both AS and CAD can cause chest pain and shortness of breath. When the cause of symptoms is in doubt, a staged approach to TAVR and PCI may be the only way to tease apart these issues. However, avoid reflexive PCI of all obstructive lesions at the time of pre-TAVR coronary angiography. Remember patients and their vessels can be vastly different regarding the complexity and risks of revascularization. The patient must be at the center of all conversations about decisions to revascularize. Discuss the specific risks and benefits of each case, and be open about uncertainties.