Abstract 14546: Left Ventricular Sphericity Index as a Predictor of Appropriate Implantable Cardioverter-defibrillator Therapy

• Published in: Circulation (New York, N.Y.) Vol. 142; no. Suppl_3 Suppl 3; p. A14546
• Main Authors: Myadam, Rahul, DʼSouza, Jason, Gosch, Kensey, Steinhaus, Daniel
• Format: Journal Article
• Language: English
• Published: by the American College of Cardiology Foundation and the American Heart Association, Inc 17.11.2020
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circ.142.suppl_3.14546

IntroductionWe assessed the hypothesis that markers of LV wall stress, such as LV sphericity index (SI), may predict appropriate therapy for ventricular arrhythmias (VA) in patients with primary prevention defibrillators, independent of LV ejection fraction.MethodsWe performed a retrospective analysis of consecutive patients with new ICD or CRT-D placement for primary prevention at a single hospital from 01/01/2015 to 06/30/2018. TTE images were used for calculating LV SI, which was defined as the ratio of bi-plane LV end-diastolic volume to the volume of a hypothetical sphere with a diameter of LV end-diastolic length in apical 4-chamber view. Device interrogations were reviewed for appropriate therapy for VA and inappropriate therapy for non-VAs. Kaplan-Meier curves stratified by LV SI tertile were constructed, and Cox proportional hazards models were used to evaluate time to appropriate and inappropriate therapy, and all-cause mortality.ResultsA total of 282 patients (ICD 154, CRT-D 128) were included. Baseline characteristics are described in the Table. We found a trend towards increased appropriate therapy as LV SI increased in the ICD but not the CRT-D group, but this was non-significant in both (ICD log-rank 0.63, p-value 0.73; CRT-D log-rank 0.07, p-value 0.96). There was no correlation between LV SI and time to all-cause mortality in the ICD (log-rank 0.53, p-value 0.76) or the CRT-D patients (log-rank 0.51, p-value 0.77). LV SI correlated significantly with time to inappropriate therapy in the ICD (log-rank 8.6, p-value 0.01), but not the CRT-D patients (log-rank 2.4, p-value 0.3).ConclusionsLV SI demonstrated a non-significant trend towards increased appropriate device therapy in the ICD but not the CRT-D group. LV SI predicted inappropriate therapy in the ICD but not the CRT-D group. Study power was limited by lower than expected event rates, possibly due to changes in device programming and improvements in heart failure therapies over time.