The Association between Left Ventricular Diastolic Dysfunction and Myocardial Scar and Their Collective Impact on All-Cause Mortality

Abstract

Left ventricular diastolic dysfunction (DD) and myocardial scar are important contributors to cardiovascular morbidity and mortality. The aim of this study was to test the hypothesis that myocardial scar is a substrate of DD and that collectively they contribute to increased risk for all-cause mortality. The study included 607 consecutive patients who underwent echocardiography and cardiac magnetic resonance imaging within 1week. DD was assessed by echocardiography according to the contemporary guidelines and myocardial scar by late gadolinium enhancement (LGE). All-cause mortality was the main outcome. Scar prevalence was significantly higher comparing no DD with mild and advanced DD (25%, 61%, and 80%, respectively; P<.001), and scar burden was greater by semiquantitative LGE scores (1.4±3.4, 4.8±6.3, and 6.8±8.8, respectively; P<.001). After 10 years of follow-up, 50 patients (8.2%) had died. The mortality incidence was significantly higher comparing no DD with mild and advanced DD (2.5, 17.3, and 55.7 deaths per 1,000 person-years, respectively; P<.001). It was also higher in patients with higher LGE scores (4.3, 22.7, and 35.2 deaths per 1,000 person-years in groups with LGE scores of 0, 1-6, and ≥7, respectively; P<.001). The risk for death was higher among patients with both DD and scar. The additive interaction of DD and scar for mortality was significant (P<.001). In the multivariate Cox proportional-hazards analysis, DD and scar were associated with mortality (P<.001). There is a strong link between the echocardiographic findings of DD and the morphologic changes of myocardial tissue. DD assessed according to contemporary guidelines effectively differentiates mortality risk. The additive interaction of DD and scar on mortality risk highlights the pivotal role of myocardial tissue characterization in patients with DD.