One author reports that he participates in software royalties for QPS Software. Rozanski and the other authors report no relevant financial disclosures.
Early revascularization may provide a mortality benefit in patients with moderate to severe myocardial ischemia identified on nuclear stress testing, regardless of left ventricular ejection fraction, researchers reported.
According to data published in the Journal of the American College of Cardiology†
“There is a lot of interest in assessing how measuring myocardial ischemia during stress testing can help determine physicians’ decision to refer patients for coronary revascularization procedures, but this issue has not been well studied in patients with underlying cardiac damage,” Alan Rozanski, MD, professor of medicine (cardiology) at the Icahn School of Medicine at Mount Sinai, director of nuclear cardiology and cardiac stress testing and chief academic officer for the department of cardiology at Mount Sinai Morningside, in a press release. “Our study, which evaluated a large number of patients with pre-existing heart damage who underwent cardiac stress testing, finally addresses this clinical void.”
Researchers identified 43,443 patients who underwent stress/rest stress-rest single-photon emission CT myocardial perfusion imaging at Cedars-Sinai Medical Center from 1998 to 2017 (mean age, 62 years; 56% males). During a median follow-up of 11.4 years, investigators evaluated revascularization for stress-induced myocardial ischemia in patients with an LVEF of less than 45% and an LVEF of 45% or greater.
Compared to patients undergoing medical therapy, those undergoing early revascularization were older, more likely males, with a higher rate of known CAD, typical angina, hypertension, hypercholesterolaemia, diabetes, MI, myocardial scar in all abnormal categories, transient ischemic dilatation, and low LVEF.
Stress testing to guide the management of myocardial ischemia
The prevalence of myocardial ischemia, assessed by nuclear stress testing, ranged from 6.7% in patients with an LVEF greater than 55% without typical angina to 64% in patients with an LVEF less than 45% and typical angina (p <.001), according to the study.
Researchers reported that in patients with LVEF greater than 45%, early revascularization was associated with an increased risk of mortality in those without ischemia and a decreased risk of mortality in those with severe ischemia identified using nuclear stress testing (HR = 0.7; 95% CI, 0.52-0.95).
In addition, early revascularization in patients with an LVEF greater than 45% was not associated with a mortality benefit in patients with no or mild ischemia, and was associated with a reduced risk of mortality in patients with moderate ischemia (HR = 0.67; 95% CI, 0.49-0.91) and severe ischemia identified by nuclear stress testing (HR = 0.55; 95% CI 0.38-0.8).
‘Aggressive Treatment’ of Severe Ischemia
“These results confirm the benefits of stress testing for clinical management. What you want from a test when considering coronary revascularization procedures is that the test identifies a large percentage of patients with low clinical risk and does it correctly, while only a small percentage of patients are identified with high clinical risk and do so. correct. That’s what we found with nuclear stress testing in this study,” Rozanski said in the release. “Importantly, the presence of severe ischemia does not necessarily mean that coronary revascularization should be performed. New data from a large clinical trial suggests that when medical therapy is optimized, it could be as effective as coronary revascularization in such patients. However, the presence of severe ischemia indicates high clinical risk, which then requires aggressive management to reduce clinical risk.”