The role of global longitudinal strain change in the assessment of early cardiotoxicity in patients receiving immune checkpoint inhibitors: a prospective pilot study of 30 patients

Abstract Background Immune checkpoint inhibitors (ICIs) improve survival in various malignancies but may cause immune-mediated cardiotoxicity. Because left ventricular ejection fraction (LVEF) typically declines late, more sensitive markers are needed for early detection of subclinical myocardial injury. This study investigated the association between changes in global longitudinal strain (GLS) and early cardiotoxicity in patients receiving ICIs. Methods In this prospective, single-center pilot study, 30 consecutive adult patients scheduled for ICI therapy were enrolled. Serial transthoracic echocardiography was performed at baseline, 6 to 8 weeks, and 12 weeks to measure LVEF using the biplane Simpson method and GLS using 2D speckle-tracking echocardiography. Cardiotoxicity was defined as a ≥ 10% absolute reduction in LVEF to < 50% and/or new-onset heart failure, suspected myocarditis, clinically significant arrhythmia, or major cardiovascular events. A relative GLS reduction ≥ 15% was considered indicative of subclinical dysfunction. Results During a mean 12-week follow-up, cardiotoxicity occurred in six patients (20.0%). In affected patients, GLS significantly deteriorated early (from − 18.2% ± 2.5% to − 14.1% ± 2.8%, P < 0.001), preceding any significant decline in LVEF. Patients without cardiotoxicity showed stable GLS and LVEF values. A ≥ 15% GLS reduction was associated with cardiotoxicity and showed exploratory discriminatory ability, with 83.3% sensitivity and 91.7% specificity (area under the curve, 0.86; 95% confidence interval, 0.72–0.97). Conclusions Early GLS deterioration was associated with cardiotoxicity despite relatively preserved LVEF. Given the temporal overlap between GLS assessment and cardiotoxicity events in several patients, these findings should be considered exploratory and hypothesis-generating.