118 - The Prognostic Value of Diastolic and Systolic Mechanical Left Ventricular Dyssynchrony among Patients with Coronary Artery Disease and Heart Failure

Abstract

Background: In patients with coronary artery disease (CAD) systolic and diastolic left ventricular mechanical dyssynchrony measured by gated single photon emission computed tomography (GSPECT) myocardial perfusion imaging (MPI) are associated with worse outcomes. Our aim was to examine the difference in prognostic effect of systolic and diastolic dyssynchrony in patients with CAD and heart failure (HF) or CAD alone. Methods: We included patients who presented to Duke University for GSPECT MPI with Myoview (GE Healthcare) between 1993 and 1999. Patients had CAD in at least one major coronary artery. We compared baseline characteristics and degree of mechanical dyssynchrony (Emory Toolbox) between CAD patients with HF and without. The distribution of dyssynchrony was compared to a control group without CAD. We performed Cox proportional hazard modeling with systolic and diastolic dyssynchrony variables for the all-cause mortality endpoint. Adjusted modeling included baseline characteristics, comorbidities, electrical dyssynchrony (QRS duration), as well as diastolic and systolic dyssynchrony parameters. Interactions between dyssynchrony variables and HF were examined in order to assess differences in the association of dyssynchrony and mortality between HF vs non-HF patients. Results: Of the 1294 patients 70% were male. HF was present in 25% of cases with a NYHA class II or III in 77% of these patients. Patients with HF had more comorbidities, higher end diastolic volumes [138 ml IQR (97–190) vs 111 ml IQR (88, 139)] and a lower ejection fraction [54% IQR (38–67) vs 63% (54–70)]. There were 537 deaths over a mean length of follow up of 6.7 years (IQR 4.9,9.3). The distribution of systolic and diastolic dyssynchrony parameters between patients with CAD + HF and CAD alone are displayed in the Fig. 1. Patients with CAD + HF had a lower survival than CAD alone at 6 years (56 %; 95% CI 50–61 vs 76%; 95% CI 73–79) and 10 years (33%; 95% CI 27–40 vs 59; 95% CI 55–62, P < .0001). HF was found to have no statistically significant interaction with dyssynchrony measures in the unadjusted and adjusted survival models. Conclusions: This is the first study to evaluate the prognostic value of systolic and diastolic mechanical dyssynchrony, as measured by GSPECT MPI, on mortality in patients with CAD + HF with mostly preserved ejection fraction. Patients with CAD + HF have a high prevalence of mechanical dyssynchrony and a higher mortality than CAD alone. However, the hazard for dyssynchrony was not different for HF vs non-HF patients. This relationship needs to be examined in patients with reduced ejection fraction.