Trajectory of left ventricular ejection fraction among individuals eligible for implantable cardioverter-defibrillator

Objective Examine the trajectory of left ventricular ejection fraction (EF) among patients eligible for implantable cardioverter-defibrillator (ICD) therapy. Background EF is the cornerstone criterion for ICD therapy, but the risk of sudden cardiac death remains after an improvement in EF. Methods We examined the trajectory of EF among 1178 participants of the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) who had three or more assessments of EF, at least 90 days apart. A follow-up EF > 35% or >10% absolute increase in EF from baseline were examined as the criteria for EF improvement. Results At first follow-up, 381 (32%) patients had an improvement of EF to >35%. However, EF had returned back to <= 35% in 109 (27%) of these patients at second follow-up. Similarly, 446 (38%) patients experienced a >10% improvement in EF at first follow-up, but 109 (24%) of these had a subsequent >10% decrease in EF at the second follow-up. Of the 32 patients with normalized EF (>= 55%) at first follow-up, 18 (56%) had a subsequent >10% decrease in EF. The fluctuation in EF was present in both ischemic and nonischemic cardiomyopathy but a higher proportion of patients with nonischemic cardiomyopathy had an improvement in EF to >35% at first follow-up compared to those with ischemic cardiomyopathy (38% vs. 27%, p = < .0001). Conclusion There is substantial fluctuation of EF among patients who are eligible for ICD therapy.

Automated summary

Among patients eligible for ICD therapy, there is significant fluctuation in left ventricular ejection fraction (EF), with some patients experiencing improvement followed by subsequent decline. Patients with nonischemic cardiomyopathy were more likely to have EF improvement to >35% at first follow-up compared to those with ischemic cardiomyopathy.