Low-Dose Dobutamine Stress Echocardiography to Assess Left Ventricular Contractile Reserve for Cardiac Resynchronization Therapy: Data From the Low-Dose Dobutamine Stress Echocardiography to Predict Cardiac Resynchronization Therapy Response (LODO-CRT) Trial

Cardiac resynchronization therapy (CRT) is an effectivemethodology indicated in selected heart failure patients. Identifying responders to the therapy is still challenging. Most studies report that at least 30% of the patients are nonresponders. Baseline characteristics of the Low-Dose Dobutamine Stress Echocardiography to Predict Cardiac Resynchronization Therapy Response (LODO-CRT) trial population are presented. The study investigates dobutamine stress echocardiography’s role in predicting CRT response. Two hundred seventy-one CRT candidates were studied. Mean age was 6710 years, 69% were male, 96% hadNew York Heart Association class III disease, and 39% had heart failure of ischemic etiology.MeanQRS and left ventricular ejection fraction were 14624 ms and 26%6%, respectively. Seventy-seven percent of participants showed contractile reserve. Left ventricular end-diastolic volume was shown to be independently associated with contractile reserve presence. In particular, more dilated ventricles are associated with a lower chance of having contractile reserve. The LODO-CRT trial enrolled a cohort of patients fulfilling criteria for CRT. Dobutamine stress echocardiography was highly feasible and safe in this population. Contractile reserve was associated with healthier ventricles.