Hemodynamic device-based optimization in cardiac resynchronization therapy: concordance with systematic echocardiographic assessment of AV and VV intervals

Background: Inappropriate settings of atrioventricular (AV) and ventriculo-ventricular (VV) intervals can be one of the factors impacting response to cardiac resynchronization therapy (CRT). Optimal concordance of AV and VV intervals between echocardiographic-based assessment and a device-based automatic programming with a hemodynamic sensor was investigated, together with left ventricle (LV) reverse remodeling after 6 months of regular automatic device-based optimization. Methods: We evaluated blindly 30 systematic echocardiographic examinations during 6 months in 17 patients (12 men, 64±10 years, in sinus rhythm and New York Heart Association class III; 76% with non-ischemic dilated cardiomyopathy, LV ejection fraction [LVEF] <35%, QRS 130 milliseconds and LV dyssynchrony) implanted with the SonRtip lead and a cardioverter-defibrillator device. Dyssynchrony (AV, VV, or intraventricular) was evaluated by an experienced operator blinded to the device programming, using conventional echocardiography, tissue synchronization imaging, tissue Doppler imaging, radial strain, and 3D echocardiography. Results: Either no AV or VV dyssynchrony (n=11; 36.7%) or a slight septal or lateral delay (n=13; 43.3%) was found in most echocardiography examinations (80%). AV or VV dyssynchrony requiring further optimization was identified in one-fifth of the examinations (20%). At 6 months, 76.5% patients were responders with LV reverse remodeling, of which 69% were super-responders (LVEF >40%). A statistically significant increase in LVEF was observed between baseline and 6 months post implant ( P <0.01). One patient died from non-cardiac causes. Conclusion: Concordance between echocardiographic methods and device-based hemodynamic sensor optimization was found in most examinations (80%) post CRT. After 6 months of systematic optimization with SonR, patients showed a statistically significant increase in LVEF, with a high rate of reverse remodeling.