It’s Time to Study Cardiac Magnetic Resonance Imaging as a Strategic Tool in Nonischemic Cardiomyopathy
Left ventricular systolic dysfunction without overt symptoms of heart failure is a common problem, with a prevalence of ranging from 0.9% to 20.8% in the general population depending on the definition of left ventricular systolic dysfunction and age group studied.1–4 The morbidity and mortality of this condition remain significant. In the SOLVD (Studies Of Left Ventricular Dysfunction) prevention trial, 30% of untreated participants progressed to clinical heart failure and experienced a high mortality rate.5 Although medical treatment reduces mortality, heart failure hospitalizations, and improves adverse remodeling,6,7 better strategies for monitoring and guiding treatment are necessary. The need for more effective methods of risk stratification is heightened by the observation that the natural history of nonischemic dilated cardiomyopathy (NIDCM) is highly variable.8 Methods to identify subgroups of patients with NIDCM who are at higher risk of adverse outcomes, especially sudden cardiac death and heart failure hospitalization, may help allocate potentially costly therapy to those who would benefit the most or to target yet unproven therapies to those most likely to benefit. Beyond medical treatments, evidence on the appropriate use of invasive strategies such as novel instruments to monitor hemodynamic status in this patient population is limited. Detection of fibrosis by late gadolinium enhancement (LGE) imaging by cardiac magnetic resonance (CMR) is a promising tool for the risk stratification in this patient population. Fibrosis reduces left ventricular compliance, affects adverse remodeling, and creates a substrate for re-entry ventricular tachycardia. Therefore, the presence of myocardial LGE would provide a logical risk marker for future adverse events relating to either mechanical pump function impairment or ventricular dysrhythmias.
Article see p 448
In this issue of Circulation: Heart Failure, Masci et al …