Time to left ventricular reverse remodeling after cardiac resynchronization therapy: Better late than never

Left ventricular reverse remodeling (LVRR), defined as reduction of end-diastolic and end-systolic dimensions and improvement of ejection fraction, is associated with the prognostic implications of cardiac resynchronization therapy (CRT). The time course of LVRR remains poorly characterized. Nevertheless, it has been suggested that it occurs ≤6 months after CRT. To characterize the long-term echocardiographic and clinical evolution of patients with LVRR occurring >6 months after CRT and to identify predictors of a delayed LVRR response. A total of 127 consecutive patients after successful CRT implantation were divided into three groups according to LVRR response: Group A, 19 patients (15%) with LVRR after >6 months (late LVRR); Group B, 58 patients (46%) with LVRR before 6 months (early LVRR); and Group C, 50 patients (39%) without LVRR during follow-up (no LVRR). The late LVRR group was older, more often had ischemic etiology and fewer patients were in NYHA class ≤II. Overall, group A presented LVRR between group B and C. This was also the case with the percentage of clinical response (68.4% vs. 94.8% vs. 38.3%, respectively, p<0.001), and hospital readmissions due to decompensated heart failure (31.6% vs. 12.1% vs. 57.1%, respectively, p<0.001). Ischemic etiology (OR 0.044; p=0.013) and NYHA functional class 6 meses após TRC, e identificar preditores de uma resposta de RIVE tardia. Cento e vinte e sete P consecutivos, após implantação bem-sucedida de TRC, foram divididos em três grupos, de acordo com a resposta de RIVE: grupo A, 19P (15%) com RIVE após seis meses (RIVE tardia); grupo B, 58P (46%) com RIVE antes dos seis meses (RIVE precoce) e grupo C, 50P (39%) sem RIVE durante o follow-up (sem RIVE). O grupo da RIVE tardia era mais velho, tinha mais etiologia isquémica e menos P em classe NYHA≥III. Globalmente, o grupo A apresentou um grau de RIVE entre os grupos B e C. O mesmo ocorreu em relação ao grau da resposta clínica (68,4 versus 94,8 versus 38,3%, respetivamente, p<0,001) e às readmissões hospitalares por descompensação da insuficiência cardíaca (31,6 versus 12,1 versus 57,1%, respetivamente, p<0,001). A etiologia isquémica (OR 0,044; p=0,013) e a classe funcional <III (OR 0,056; p=0,063) foram as variáveis com maior valor preditor para a ocorrência de RIVE tardia. A RIVE tardia tem uma melhor resposta clínica e ecocardiográfica do que a ausência de RIVE, embora com uma resposta subótima, quando comparada com a população com RIVE precoce. A etiologia isquémica e uma classe NYHA