VitaminD deficiency and functional response to CRT inheart failure patients

BackgroundVitaminD deficiency has been associated with apoor outcome in patients with heart failure (HF). We examined the role of vitaminD in the response of HF patients to cardiac resynchronization therapy (CRT).MethodsThe study comprised 50patients (30men and 20women) with HF undergoing CRT implantation who were prospectively enrolled. Response to CRT was defined as acombination of 15% reduction in left ventricular end-systolic volume (LVESV) and 10% improvement in the 6-Minute Walk Test within 6months. Patients were grouped based on their levels of vitaminD prior to CRT implantation. Clinical and echocardiographic examinations were performed prior to and 6months after the procedure.ResultsOf the patients, 11 (22%) failed to respond to CRT; two patients died within 6months and an additional nine patients showed no improvement in the 6-Minute Walk Test and no reduction in their baseline LVESV. A comparison was made between 25patients with sufficient levels of vitaminD and 25patients with insufficient levels. Nine patients (36%) in the insufficient group and two patients (8%) in the sufficient group failed to respond to CRT implantation (p= 0.037).ConclusionAdequate serum concentrations of vitaminD play asignificant role in improving the functional status of patients with systolic HF following CRT implantation.