Vasodilator Stress CMR and All-Cause Mortality in Stable Ischemic Heart Disease: A Large Retrospective Registry

Abstract

Objectives: This study explored the association of ischemic burden, as measured by vasodilator stress cardiovascular magnetic resonance (CMR), with all-cause mortality and the effect of revascularization on all-cause mortality in patients with stable ischemic heart disease (SIHD).

Background: In patients with SIHD, the association of ischemic burden, derived from vasodilator stress CMR, with all-cause mortality and its role for decision-making is unclear.

Methods: The registry consisted of 6,389 consecutive patients (mean age: 65 ± 12 years; 38% women) who underwent vasodilator stress CMR for known or suspected SIHD. The ischemic burden (at stress first-pass perfusion imaging) was computed (17-segment model). The effect of CMR-related revascularization (within the following 3 months) on all-cause mortality was retrospectively explored using the electronic regional health system registry.

Results: During a 5.75-year median follow-up, 717 (11%) deaths were documented. In multivariable analyses, more extensive ischemic burden (per 1-segment increase) was independently related to all-cause mortality (hazard ratio: 1.04; 95% confidence interval: 1.02 to 1.07; p < 0.001). In 1,032 1:1 matched patients using a limited number of variables (516 revascularized, 516 non-revascularized), revascularization within the following 3 months was associated with less all-cause mortality only in patients with extensive CMR-related ischemia (>5 segments, n = 432; 10% vs. 24%; p = 0.01).

Conclusions: In a large retrospective registry of unselected patients with known or suspected SIHD who underwent vasodilator stress CMR, extensive ischemic burden was related to a higher risk of long-term, all-cause mortality. Revascularization was associated with a protective effect only in the restricted subset of patients with extensive CMR-related ischemia. Further research will be needed to confirm this hypothesis-generating finding.

Keywords: all-cause mortality; cardiovascular magnetic resonance; ischemic burden; ischemic heart disease; prognosis; revascularization.