Prediction of clinical outcome in patients treated with cardiac resynchronization therapy - the role of NT-ProBNP and a combined response score.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an established therapy for appropriately selected patients with heart failure. Response to CRT has been heterogeneously defined using both clinical and echocardiographic measures, with poor correlation between the two. METHODS: The study cohort was comprised of 202 CRT-treated patients and CRT response was defined at 6 months post-implant. Echocardiographic response (E+) was defined as a reduction in LVESV ≥ 15%, clinical response as an improvement of ≥ 1 NYHA class (C+), and biomarker response as a ≥ 25% reduction in NT-proBNP(B+). The association of response measures (E+, B+, C+; response score range 0-3) and clinical endpoints at 3 years was assessed in landmarked Cox models. RESULTS: Echo and clinical responders demonstrated greater declines in NT-proBNP than non-responders (median [E+/B+]: -52%, [E+]: -27%, [C+]: -39% and [E-/C-]: -13%; p = 0.01 for trend). Biomarker (HR 0.43 [95% CI: 0.22-0.86], p = 0.02) and clinical (HR 0.40 [0.23-0.70] p = 0.001) response were associated with a significantly reduced risk of the primary endpoint. When integrating each response measure into a composite score, each 1 point increase was associated with a 31% decreased risk for a composite endpoint of mortality, LVAD, transplant and HF hospitalization (HR 0.69 [95% CI: 0.50-0.96], p = 0.03), and a 52% decreased risk of all-cause mortality (HR 0.48 [95% CI: 0.26-0.89], p = 0.02). CONCLUSION: Serial changes in NT-proBNP are associated with clinical outcomes following CRT implant. Integration of biomarker, clinical, and echocardiographic response may discriminate CRT responders versus non-responders in a clinically meaningful way, and with higher accuracy. TRIAL REGISTRATION: The cohort was combined from study NCT01949246 and the study based on local review board approval 2011/550 in Lund, Sweden.

Semi-automated QRS score as a predictor of survival in CRT treated patients with strict left bundle branch block.

BACKGROUND: Cardiac Resynchronization Therapy (CRT) is widely used for treating selected heart failure patients, but patients with myocardial scar respond worse to treatment. The Selvester QRS scoring system estimates myocardial scar burden using 12-lead ECG. This study's objective was to investigate the scores correlation to mortality in a CRT population. METHODS AND RESULTS: Data on consecutive CRT patients was collected. 401 patients with LBBB and available ECG data were included in the study. QuAReSS software was used to perform Selvester scoring. Mean Selvester score was 6.4, corresponding to 19% scar burden. The endpoint was death or heart transplant; outcome was analyzed using Cox proportional hazards models. A Selvester score >8 was significantly associated with higher risk of the combined endpoint (HR 1.59, p=.014, CI 1.09-2.3). CONCLUSION: Higher Selvester scores correlate to mortality in CRT patients with strict LBBB and might be of value in prognosticating survival.