Abstract 16824: Transmural Myocardial Scar Assessed by Cardiac Computed Tomography Predicts Response to Cardiac Resynchronization Therapy
Introduction: Myocardial scar located near the left ventricular (LV) lead and scar burden negatively influence the response to cardiac resynchronization therapy (CRT). Cardiac computed tomography (CT) can visualize scar and cardiac veins available for LV lead placement. Thus, this modality potentially may be of value in guiding the CRT procedure.
Hypothesis: We hypothesized that localization and burden of transmural myocardial scar verified by cardiac CT is associated with CRT response.
Methods: We prospectively included 139 patients (New York Heart Association class II-IV, mean [SD] LV ejection fraction 25  %, optimal medical treatment, left bundle branch block with mean [SD] QRS width 167  msec, mean [SD] age 70  years, number [%] female 31 [22%]) undergoing cardiac CT before CRT implantation. Transmural myocardial scar was determined by the presence of hypo-perfusion involving >1/2 of the myocardial wall assessed in each segment using a 17-segment model. Response to CRT was defined as ≥5% absolute increase in LV ejection fraction 6 months after implantation. The LV lead position was determined by cardiac CT. Evaluation of transmural myocardial scar by cardiac CT was performed blinded to echocardiographic data.
Results: Among patients with ≥1 transmural scarred segment, we found worse CRT outcome if a scarred segment was localized concordant or adjacent to the LV lead position (odds ratio [OR]: 8.2; 95% confidence interval [CI]: 1.51 to 44.27; P=0.015). The presence of transmural myocardial scar in ≥5 segments was associated to CRT non-response in comparison to patients without any transmural scar (OR: 3.02; 95% CI: 1.03 to 8.91; P=0.045).
Conclusion: Cardiac CT verified transmural myocardial scar localized near the LV lead and burden of transmural scar tissue is associated with non-response to CRT. Cardiac CT may be a valuable pre-implant imaging modality in CRT recipients.
Author Disclosures: D.B. Fyenbo: None. A. Sommer: None. J.T. Kühl: None. K.F. Kofoed: Research Grant; Modest; AP Møller og hustru Chastine McKinney Møllers Fond, The John and Birthe Meyer Foundation, Research Council of Rigshospitalet, The University of Copenhagen, The Danish Heart Foundation, The Lundbeck Foundation, The Danish Agency for Science, Technology and Innovation by The Danish Council for Strategic Research, Toshiba Medical Corporation. Speakers Bureau; Modest; Toshiba Medical Systems. Consultant/Advisory Board; Modest; VITAL Images Inc. B.L. Nørgaard: Research Grant; Modest; Edwards Lifesciences, Siemens, HeartFlow. M.B. Kronborg: None. K. Bouchelouche: None. J.C. Nielsen: None.
- © 2016 by American Heart Association, Inc.