Sites of latest mechanical activation as assessed by SPECT myocardial perfusion imaging in ischemic and dilated cardiomyopathy patients with LBBB

• Type of Material: Article
• Authors: Xianhe Lin, Anhui Medical University; Huiqin Xu, Anhui Medical University; Xuefeng Zhao, Anhui Medical University; Ji Chen, Emory University
• Language: English
• Date: 2014-06-01
• Publisher: Springer Verlag (Germany)
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2014 Springer-Verlag Berlin Heidelberg.
• Final Published Version (URL): http://dx.doi.org/10.1007/s00259-014-2718-6
• Title of Journal or Parent Work: European Journal of Nuclear Medicine and Molecular Imaging
• ISSN: 1619-7070
• Volume: 41
• Issue: 6
• Start Page: 1232
• End Page: 1239
• Grant/Funding Information: This study was supported in part by a USA NIH grant (1R01HL094438, PI: Ji Chen, PhD).
• Keywords: Phase analysis; CARDIAC-RESYNCHRONIZATION THERAPY; LEFT-VENTRICULAR DYSSYNCHRONY; Radiology, Nuclear Medicine & Medical Imaging; QRS DURATION; TISSUE; MAGNETIC-RESONANCE; REVERSE; LV dyssynchrony; PHASE-ANALYSIS; Cardiac resynchronization therapy; CHRONIC HEART-FAILURE; Science & Technology; SPECT myocardial perfusion imaging; Life Sciences & Biomedicine; CONDUCTION DELAY; PREDICTS RESPONSE
• Research Categories: Health Sciences, Medicine and Surgery; Health Sciences, Radiology

Abstract

Objective: Sites of latest mechanical activation (SOLA) have been recognized as optimal left-ventricular (LV) lead positions for cardiac resynchronization therapy (CRT). This study was aimed to investigate SOLA in ischemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM) patients with left bundle branch block (LBBB). Methods: Sixty-four consecutive LBBB patients (47 DCM, 17 ICM), who met the standard indications for CRT and underwent resting SPECT myocardial perfusion imaging (MPI), were selected. Phase analysis was used to assess LV dyssynchrony and SOLA. The Emory Cardiac Toolbox was used to measure perfusion defects. LV dyssynchrony and SOLA were compared between the DCM patients with wide (≥150 ms) and moderate (120-150 ms) QRS durations (QRSd). The relationship between SOLA and perfusion defects was analyzed in the ICM patients. Results: The DCM patients with wide QRSd had significantly more LV dyssynchrony than those with moderate QRSd. Lateral SOLA were significantly more frequent in the DCM patients with wide QRSd than those with moderate QRSd (96 % vs. 62 %, p=0.010). In the ICM patients, SOLA were either in the scar segments (82 %) or in the segments immediately adjacent to the scar segments (18 %), regardless of QRSd. Conclusion: Lateral SOLA were more frequent in the DCM patients with wide QRSd than those with moderate QRSd. Such relationship was not observed in the ICM patients, where SOLA were associated with scar location rather than QRSd. These findings support the use of SPECT MPI to aid the selection of potential CRT responders and guide LV lead placement.