Noncardiac Surgery Riskier After Incomplete vs Complete Revascularization, Observational Study Finds

Patients who have noncardiac surgery within 2 years of undergoing incomplete revascularization of multivessel disease face a higher risk of MACE, especially MI, than those whose revascularization had been complete, according to an observational study.

The data, presented at last year’s American Heart Association Scientific Sessions, are now being published along with an accompanying editorial in JACC: Cardiovascular Interventions.

While these findings “should be interpreted as showing that prior CAD and recent PCI is a marker for poorer outcomes,” they should not “be construed as justification that patients with prior PCI and either complete or incomplete revascularization should undergo routine stress testing,” write editorialists Kim Eagle, MD (University of Michigan, Ann Arbor), and Debabrata Mukherjee, MD (Texas Tech University Health Sciences Center, El Paso).

In the study by Ehrin Armstrong, MD, MSc (Denver VA Medical Center, CO), of more than 12,000 veterans who received major noncardiac surgery within 2 years of PCI, roughly one-third had incomplete revascularization—defined as a residual stenosis of ≥ 50% in the left main coronary artery or ≥ 70% in another major epicardial coronary artery. These patients were at a 19% higher risk of MACE at 30 days compared with those who received complete revascularization (OR 1.19; 95% CI 1.00-1.41). This association was driven by a 37% increased risk of MI (OR 1.37; 95% CI 1.10-1.70).

Additionally, timing and the number of vessels played a role. Patients who received noncardiac surgery within 6 weeks of PCI were much more likely to report postoperative MI (adjusted OR 1.84; 95% CI 1.04-2.38), and there was a 17% increased risk of this outcome for each additional vessel with incomplete revascularization.

Even with the “important differences” in baseline characteristics between patients who received incomplete versus complete revascularization—with the former group being more likely to have had an MI in the past 6 months, a history of congestive heart failure, diabetes, and a greater burden of atherosclerotic disease—“the salutary effects of coronary revascularization either complete or incomplete is questionable/unproven,” Eagle and Mukherjee write.

It seems “reasonable,” they say, to delay surgery for at least 6 weeks after PCI in general and ideally for at least 6 months after DES implantation.

What About Stress Testing?

Eagle and Mukherjee note that routine stress testing is not indicated for noncardiac surgery patients who have a history of PCI. Rather, they say, ather it holds a Class III indication in the current American College of Cardiology/American Heart Association guidelines and “not considered useful for patients at low risk for noncardiac surgery.”

However, Armstrong and colleagues write that their results suggest “that risk stratification using cardiac stress testing in a select subset of patients with known residual angiographic stenosis may be a way to impact postoperative morbidity.”

The editorialists call this a “speculative” idea. “There is no evidence that in stable patients either intensifying treatment or additional revascularization (if feasible) prior to noncardiac surgery is beneficial, and it may possibly cause harm,” they say. “Every attempt should be made to use guideline-based medical therapy in the perioperative period which may include antiplatelet therapies, statins, and beta-blockers in appropriate patients.”

The ongoing ISCHEMIA trial should help with these decisions, Eagle and Mukherjee add. “This study, while not directly addressing the subset of patients undergoing noncardiac surgery will provide important insight into optimal managements for higher-risk patients with stable ischemic heart disease and at least moderate ischemia,” they write.