ABSTRACT
Despite improvement in morbidity and mortality with cardiac resynchronization therapy (CRT), disease progression continues to affect a subset of patients and there is limited effort to identify contributing factors. Our objective was to investigate if a protocol-driven approach incorporated in a management strategy of heart failure immediately after implantation would provide incremental benefits beyond usual care after implantation. We reviewed 114 consecutive patients with CRT implanted from 2005 through 2009 who received usual care after implantation or underwent protocol-driven CRT care after implantation. Preimplantation characteristics in patients receiving usual versus protocol-driven care were similar in left ventricular (LV) dimension (LV internal diastolic diameter 6.2 ± 0.8 vs 6.4 ± 1.0 cm), LV ejection fraction (26 ± 8% vs 25% ± 8%), QRS width, and medication usage. Major adjustments during the protocol-driven approach were uptitration of neurohormonal blockers (64%), echocardiographically guided atrioventricular optimization (50%), heart failure education (42%), arrhythmia management (19%), and LV lead repositioning (7%). Although positive LV remodeling was noted in the 2 groups at 6 months, extent was significantly greater in the protocol-driven approach compared to usual care (change in LV internal diastolic diameter 0.7 ± 0.6 cm vs 0.2 ± 1.2 cm, p = 0.01; change in LV ejection fraction 11 ± 7% vs 7 ± 9%, p = 0.01), which was associated with fewer major adverse events (14% vs 53%, p <0.001). In conclusion, a protocol-driven approach for patients with CRT started immediately after implantation is associated with incremental favorable effects on reverse remodeling and fewer adverse events compared to usual care after implantation. These effects appeared to be driven not only by changes in device settings and arrhythmia management but also by concomitant medication optimization and heart failure education.
