Cardiac Resynchronization Therapy Guided by Echocardiography, MRI, and CT Imaging: A Randomized Controlled Study.
OBJECTIVES
This study evaluated if selecting the left ventricular (LV) target segment by echocardiography-derived late mechanical activation, with access to multimodality imaging for scar and venous anatomy, could help to increase responder rates to cardiac resynchronization therapy (CRT).


BACKGROUND
LV lead placement is important for clinical outcome, but the optimal strategy for LV lead placement in CRT is still debated.


METHODS
This study conducted a prospective, blinded randomized controlled trial on 102 patients with indication for CRT (27% women, 46% with ischemic cardiomyopathy, 63% in New York Heart Association functional class III, 74% with left bundle branch block, and with mean ejection fraction of 23%). Optimal LV lead location was defined as the latest mechanically activated available segment (free of transmural scar), determined by radial strain echocardiography, cardiac computed tomography, and cardiac magnetic resonance (n = 70). The primary endpoint was reduction of LV end-systolic volume by ≥15% at 6 months post-implantation.


RESULTS
Patients were followed for 47 ± 21 months. Based on imaging, optimal or adjacent lead placement was feasible in 96% of all cases and was obtained in 83% of the intervention group versus 80% of the control group. Fifty-six percent of the patients were LV end-systolic volume responders compared with the control group (55%) (p = 0.96), and 71% improved ≥1 New York Heart Association functional class (74% vs. 67%; p = 0.43). Death or heart failure hospitalization within 2 years occurred in 6% (2% of the intervention group vs. 10% of the control group; p = 0.07).


CONCLUSIONS
Radial strain-guided LV lead placement, in combination with multimodality imaging, did not result in increased clinical or echocardiographic response, nor in a significant reduction of death or heart failure hospitalization. (Combining Myocardial Strain and Cardiac CT to Optimize Left Ventricular Lead Placement in CRT Treatment [CRT Clinic]; NCT01426321).
['Borgquist|Rasmus|R|', 'Carlsson|Marcus|M|', 'Markstad|Hanna|H|', 'Werther-Evaldsson|Anna|A|', 'Ostenfeld|Ellen|E|', 'Roijer|Anders|A|', 'Bakos|Zoltan|Z|']
D058406:Cardiac Resynchronization Therapy D004452:Echocardiography D005260:Female D006333:Heart Failure D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D011446:Prospective Studies D014057:Tomography, X-Ray Computed
cardiac resynchronization therapy echocardiography multimodality imaging heart failure cardiac CT cardiac MRI left ventricular lead position