Prognostic significance of persistent restrictive filling pattern after cardiac resynchronization therapy.

Abstract

Cardiac resynchronization therapy (CRT) may improve left ventricular (LV) diastolic dysfunction as well as systolic dysfunction. Diastolic dysfunction is a key for prognosis in patients with heart failure; therefore, we aimed to clarify the impact of CRT on diastolic function and prognosis. In 67 patients who underwent CRT, LV diastolic function was assessed by pulsed Doppler transmitral flow pattern at baseline and 1 week after CRT, and classified into restrictive filling pattern (RFP) and non-RFP groups. Volume responders were defined by reduction of LV end-systolic volume >15% at 6 months after CRT. The clinical endpoint comprised death from any cause or unplanned hospitalization for a major cardiovascular event (MACE). During the follow-up period (479 ± 252 days), 26 patients (38.8%) had reached the endpoint of MACE. In Cox proportional hazard analyses, RFP at 1 week after CRT was associated with the endpoints independently of age and New York Heart Association (NYHA) class IV at baseline. Thirty (44.8%) patients were identified as volume responders, who had better prognosis than non-responders. Patients were classified into 4 groups based on their filling pattern at 1 week after CRT and volume responses. The worst prognosis was observed in the RFP and non-responder group, and the best was observed in the non-RFP and responder group. For the remaining 2 groups with intermediate prognosis, the RFP and responder group showed poorer prognosis compared to the non-RFP and non-responder group. Persistent RFP after CRT may be a strong prognostic predictor, which should be treated with more intensive therapy to improve the prognosis of patients following CRT.