Mid-Q Response Study
The Mid-Q Response study is a prospective, multi-center, randomized controlled, interventional, single-blinded, post-market study. The purpose of the Mid-Q Response study is to test the hypothesis that the AdaptivCRT (aCRT) algorithm is superior to standard CRT therapy regarding patient outcomes in CRT indicated patients with moderate QRS duration, preserved atrioventricular (AV) conduction and left bundle branch block (LBBB). The study will be executed at approximately 60 centers in Asia. The subjects will be randomly assigned in a 1:1 ratio to the aCRT ON (Adaptive Bi-V and LV) group or the aCRT OFF (Nonadaptive CRT) group. The primary objective is to test the hypothesis that aCRT ON increases the proportion of patients that improve on the Clinical Composite Score (CCS) compared to aCRT OFF at 6 months of follow-up.
• Subject is willing to sign and date the study Informed Consent Form (ICF).
• Subject is indicated for a CRT device according to local guidelines.
• Subject has sinus rhythm at time of enrollment
• Subject has a moderately wide intrinsic QRS duration ≥120 ms and \<150 ms
• Subject has Left Bundle Branch Block (LBBB) as documented on an ECG (preferably within 30 days prior to enrollment but up to 50 days is accepted) with Qs or rS in leads V1 and V2, and Mid-QRS notching or slurring in ≥2 of leads V1, V2, V5, V6, I, and aVL
• Subject has intrinsic, normal AV conduction as documented on an ECG by a PR interval ≤200 ms (preferably within 30 days prior to enrollment but up to 50 days is accepted).
• Subject has left ventricular ejection fraction ≤35% (documented within 180 days prior to enrollment).
• Subject has NYHA class II, III, or IV (documented within 30 days prior to enrollment) despite optimal medical therapy. Optimal medical therapy is defined as maximal tolerated dose of Beta-blockers and a therapeutic dose of ACE-I, ARB or MRA.