Left Ventricular Global Longitudinal Strain Is Associated With Appropriate Therapies for Ventricular Arrhythmias Independent of Left Ventricular Ejection Fraction in Patients With Primary Prevention Defibrillators

Background: Left ventricular ejection fraction (LVEF) has not demonstrated reliability in predicting ventricular arrhythmias or appropriate implantable cardioverter defibrillator (ICD) therapy (AICDt). Objective: To evaluate the association between left ventricular global longitudinal strain (GLS) and AICDt. Methods: One hundred seventy-eight consecutive patients who received ICD implants for primary prevention of sudden cardiac death from 1/16/2015 to 1/26/2022 were followed until 1st appropriate ICD therapy (AICDt) for a ventricular arrhythmia, death, or loss to follow-up. AICDt were physician adjudicated. Covariates included demographic variables (age, sex), clinical risk factors (LVEF, cardiac resynchronization therapy, coronary artery disease, anti-arrhythmic drug use, QRS duration), and variables from the DO-IT model (nonsustained ventricular tachycardia, atrial fibrillation, glomerular filtration rate, peripheral vascular disease, direct oral anticoagulant use, digoxin use, aldosterone antagonist use, and angiotensin converting enzyme inhibitor/angiotensin II receptor blocker use). Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI₉₅) of GLS per 5% decrease (absolute value) for AICDt. Results: Over a mean (standard deviation) follow up period of 5.09 (2.11) years, 44 of the 178 patients (79.77% male, 63.89 (12.89) years of age) in the final cohort experienced AICDt. In patients with coronary artery disease, GLS per 5% decrease (absolute value) was associated with AICDt independent of demographic variables (HR 2.16, CI₉₅ 1.09–4.27), clinical risk factors (HR 2.54, CI₉₅ 1.16–5.59), and variables from the DO-IT model (HR 3.28, CI₉₅ 1.46–7.36). Conclusion: Reduced GLS (absolute value) is an independent risk factor for AICDt in patients with coronary artery disease.