Abstract 4855: Influence of Left Ventricular End Diastolic Diameter Index on Clinical Outcomes with Cardiac Resynchronization: Insights from the COMPANION Study
Background: Although cardiac resynchronization therapy (CRT) has been shown to slow the progression of heart failure (HF), it has not been well described whether the baseline severity of ventricular remodeling influences clinical outcomes.
Methods: The COMPANION study database was analyzed retrospectively. This study randomized patients (pts) with NYHA Class III/IV HF, wide QRS, and systolic dysfunction to optimal pharmacologic therapy (OPT) alone or to OPT plus CRT either with (CRT-D) or without a defibrillator (CRT-P). For this analysis both CRT arms were combined. Ventricular remodeling was measured as left ventricular end diastolic dimension indexed by body surface area (LVEDDI). Data were stratified around the median value: LVEDDI≥ 35 mm/m2 and < 35 mm/m2. CRT was compared to OPT for each cohort using functional outcomes at six months [exercise capacity, quality of life, functional status, and the Clinical Composite Endpoint] as well as event-driven outcomes [all-cause mortality alone and in combination with cause-specific hospitalization].
Results: Baseline LVEDDI data were available for 1260 pts. Pts in the larger LVEDDI cohort were characterized at baseline with wider QRS, lower EF, and a greater proportion of non-ischemic, female, and NYHA Class IV. Clinical outcomes are summarized below:
Conclusion: In the COMPANION study, both cohorts demonstrated significant benefit in functional outcomes with CRT when compared to OPT. However, significant improvement in event-driven outcomes were seen only in the population with larger baseline LVEDDI. A prospective study is needed to confirm that LVEDDI can predict potential for improvement with CRT.