Within this viability substudy, CABG was associated with a lower risk of all-cause death through a median follow-up of 10.4 years when compared with medical therapy alone (62% vs 69% adjusted HR 0.73 95% CI 0.60-0.90), echoing what was seen in the overall trial. There is a constellation of issues that are related to the decision, of which myocardial viability is merely one of them. According to that testing, 81% of patients had viable myocardium and the rest did not. Of the 1,212 patients with CAD suitable for CABG and an LVEF of < 35% randomized in STICH, about half (49.6%) underwent a baseline assessment of myocardial viability using single-photon-emission CT, dobutamine echocardiography, or both. Why Doesn’t Myocardial Viability Influence Outcomes? “It doesn’t completely by itself drive the decision, but it’s a piece of information that they still feel is important.” “What we see is that the surgeons still want this information to inform their decision,” he commented to TCTMD.
James Udelson, MD (Tufts Medical Center, Boston, MA), who was not involved in the study, agreed, noting that there is a body of observational evidence to suggest that patients with-but not those without-viable myocardium benefit from revascularization. So there is a constellation of issues that are related to the decision, of which myocardial viability is merely one of them.” “But the test of viability should be taken in the context of the coronary anatomy, the degree of left ventricular dysfunction, and the ability to do an effective bypass in the vessels that are stenotic and supplying the dysfunctional myocardium. “This is a very complex population of patients and the decision as to whether an individual patient should or should not undergo bypass surgery should not be based on the result of a single test-ie, a test of viability,” he said. Still, Panza said, myocardial viability testing continues to have a role in the decision-making process around CABG. Now, using the 10-year data, the investigators have come to the same conclusion they did 5 years earlier, as reported in a study published in the August 22, 2019, issue of the New England Journal of Medicine.
“That generated a lot of debate because it was counter to the accepted belief that in order to undergo bypass surgery these patients need to have demonstration of viability,” lead author of the new analysis Julio Panza, MD (Westchester Medical Center, Valhalla, NY), explained to TCTMD. At that time, STICH researchers also observed that the presence of viable myocardium prior to surgery did not identify patients who were more likely to benefit from surgical revascularization. Those findings mirror the conclusions reached at the 5-year mark, researchers report today.Īs previously published, death from any cause occurred less frequently among patients with coronary disease and severe LV dysfunction who underwent CABG versus those among who received optimal medical therapy alone, a difference that reached statistical significance only after 10 years of follow-up in the STICHES extension study (58.9% vs 66.1% P = 0.02).Īn earlier publication at 5 years showed a similar trend, though the difference was not significant (36% vs 41% P = 0.12). The presence of myocardial viability at baseline was not a predictor of the long-term mortality reduction attained with CABG in patients with ischemic cardiomyopathy in the STICH trial, even when follow-up was extended out to 10 years.