Ischemic mitral regurgitation severity, infarct size help explain risk in cardiomyopathy
Click Here to Manage Email Alerts
Among patients with ischemic cardiomyopathy who underwent cardiac magnetic resonance, the interaction of ischemic mitral regurgitation severity and myocardial infarct size predicted adverse outcomes, researchers reported.
“Our study highlights the important and comprehensive assessment that cardiac magnetic resonance (CMR) provides for patients with ischemic mitral regurgitation (IMR),” Deborah H. Kwon, MD, medical director of cardiac MRI at Cleveland Clinic, told Healio. “Our study suggests that risk associated with significant IMR should not be determined in isolation, but is more completely assessed when it is described in the context of myocardial infarct size. It will be important to determine if CMR can provide not only more robust risk stratification, but also to determine if comprehensive CMR evaluation can be used to develop patient selection criteria for determining which patients will derive the most benefit from potential transcatheter-based interventions.”
João L. Cavalcante, MD, FACC, FASE, FSCCT, FSCMR, scientific director of the Minneapolis Heart Institute Foundation Cardiovascular Imaging Research Center and Core Lab, and colleagues performed CMR on 578 consecutive patients with ischemic cardiomyopathy (mean age, 62 years; 76% men).
The primary outcome was all-cause mortality or cardiac transplant. Mean follow-up was 4.9 years. Myocardial infarct size was quantified as proportion of left ventricular mass by late gadolinium enhancement imaging. IMR severity was quantified by calculating mitral regurgitant fraction (MRFraction) by CMR.
During the study period, 34% of patients achieved the primary endpoint.
After adjustment for comprehensive medical risk score, subsequent revascularization, insertion of implantable cardioverter defibrillator and surgical mitral valve intervention, the interaction of ischemic mitral regurgitation severity and myocardial infarct size was a strong predictor of the primary endpoint (P = .008), according to the researchers.
Among patients with significant IMR, defined as MRFraction 35% or greater, there was no significant difference in the primary endpoint between those with moderate myocardial infarct size (15% to 29%) and those with small myocardial infarct size (less than 15%; HR = 1.51; 95% CI, 0.57-3.98), but those with large myocardial infarct size (30% or more) had greater risk than those with small infarct size (HR = 5.41; 95% CI, 2.34-12.7), the researchers wrote.
“Taken together, these results show that CMR is an important noninvasive imaging modality, not only for risk stratification but also for the individualization of treatment decisions for these complex patients,” Cavalcante and colleagues wrote. – by Erik Swain
For more information:
Deborah H. Kwon, MD, can be reached at Imaging Institute, Department of Cardiovascular
Medicine, Cleveland Clinic, 9500 Euclid Ave., Desk J1-5, Cleveland, OH 44195; email:
kwond@ccf.org; Twitter: @debbiekwonmd.
Disclosures: Cavalcante reports he received consultant fees from Abbott Vascular and Boston Scientific; has received research grant support from Abbott Vascular, Boston Scientific, Edwards Lifesciences, Medtronic and Siemens Healthineers; and has been a speaker for Circle Cardiovascular Imaging, Medtronic and Siemens Healthineers. The other authors report no relevant financial disclosures.
Click Here to Manage Email Alerts