Does 'super-responder' patients to cardiac resynchronization therapy still have indications for neuro-hormonal antagonists? Evidence from long-term follow-up in a single center.

BACKGROUND: Whether cardiac resynchronization therapy super-responders (CRT-SRs) still have indications for neuro-hormonal antagonists or not remains uninvestigated. METHODS: We reviewed clinical data from 376 patients who underwent CRT implantation in Fuwai Hospital from 2009 to 2015 and followed up to 2017. CRT-SRs were defined by an improvement of the New York Heart Association functional class and left ventricular ejection fraction to ≥ 50% in absolute values at 6-month follow-up. All CRT-SRs were assigned into two groups on the basis of whether persistently receiving neuro-hormonal antagonists (NHA) (defined as angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and ß-blockers) after 6-month follow-up and then we compared long-term outcome. RESULTS: A total of 60 patients met criteria for super-response. One of thirteen (7.7%) CRT-SRs without NHA had all-cause death, which also occurred in 2 of 47 (4.3%) in CRT-SRs with NHA (P = 0.526). However, 3 of 13 (23.1%) CRT-SRs without NHA had heart failure (HF) hospitalization, 1 of 47 (2.1%) CRT-SRs with NHA had this endpoint (P = 0.040). Besides, subgroup analysis indicated that, for ischemic etiology group, CRT-SRs receiving NHA had considerably lower incidence of HF hospitalization than those without NHA (0 vs. 75%, P = 0.014), which was not observed in non-ischemic etiology group (2.6% vs. 0, P = 1.000) during long-term follow-up. CONCLUSIONS: Our study found that for ischemic etiology, compared with CRT-SRs with NHA, CRT-SRs without NHA were associated with a higher risk of HF hospitalization. However, for non-ischemic etiology, we found that CRT-SRs with NHA or without NHA at follow-up were associated with similar outcomes, which needed further investigation by prospective trials.