Abstract 13783: Additive Value of Severe Diastolic Dysfunction and Contractile Reserve in the Identification of Responders to Cardiac Resynchronization Therapy
Background: The identification of responders remains challenging in cardiac resynchronization therapy (CRT). Aim of the study was to assess the role of myocardial contractile reserve (CR) during dobutamine stress echo (DSE) and resting severe diastolic dysfunction to identify responders to CRT.
Methods: Sixty eight patients (57% with ischemic etiology, mean value of ejection fraction: 27±5%) referred to CRT underwent baseline echocardiography and high dose of DSE. CR was evaluated using pressure volume relationship (PVR), defined as systolic cuff pressure/end-systolic volume index difference between rest and peak DSE. We defined severe diastolic dysfunction: presence of restrictive transmitral patterns and/or E/Ea >15. Adverse events during follow-up were identified by presence of clinical events and absence of LV reverse remodeling (end-systolic volume decrease ≥15%).
Results: During median follow-up of 18 months, patients with CR showed higher presence of reverse remodeling (84% vs 41%, p=.001, X2 11.65) and lower incidence of adverse events (25% vs 72%, p<.001, X2 14.91). Similarly, reverse remodeling was higher in absence severe diastolic dysfunction (74% vs 44%, p=.017, X2 5.71), with lower incidence of adverse events (41% vs 65%, p=.037, X2 4.05). Event free survival after CRT was poorer in patients without CR and with severe diastolic dysfunction (Figure), with additive value for the presence of reverse remodeling (X2 12.37, p=.006) and adverse events (X2 15.84, p=.001).
Conclusion: Patients with CR in absence of baseline severe diastolic dysfunction show a favorable clinical and echocardiographic outcome in the follow-up after CRT
- © 2010 by American Heart Association, Inc.