Abstract 20041: Left Ventricular Contractile Reserve by Stress Echocardiography as a Predictor of Response to Cardiac Resynchronization Therapy in Heart Failure: A Meta-Analysis
Background: Left ventricular contractile reserve (CR) during stress echo (SE) may predict favorable response to cardiac resynchronization therapy (CRT) in heart failure patients.
Hypothesys: To perform a meta-analysis of available SE data in this set of patients.
Methods: All studies published in international peer-reviewed journals were included in the meta-analysis if they fulfilled the following criteria: 1- heart failure patients with NYHA class III and IV, depressed ejection fraction (EF < 35%) and QRS duration ≥ 120 ms at study entry; 2- SE with assessment of CR; 3- Clinical and/or echocardiographic follow-up information after CRT. Large part of CR during SE was identified as a reduction in wall motion score index < 0.20, and/or an increase in ejection fraction > 5%. Responders to CRT were identified on the basis of symptomatic (NYHA class decrease) and/or functional (reduction in LV end-systolic volume > 15%) improvement in the follow-up post-CRT.
Results: From Pubmed scan from 2006 to 2015, 13 studies with 1002 patients (mean age 67±3 years, 73% male, 54% with ischemic cardiomyopathy) were included in the meta-analysis. The type of stress was either exercise (n=2) or dobutamine (n= 11), the latter with low dose (up to 10 mcg) in 2, intermediate dose (up to 20 mcg) in 7, and high dose (40 mcg) protocol in 2 studies; 609 patients (61%) showed CR and 644 (64%) were responders to CRT. Resting ejection fraction was 25±3%, QRS duration 157±12 ms, end-diastolic and end-systolic volumes were 202±41 ml and 150±32 ml, respectively. The overall odds ratio for CR to predict a favourable CRT response was 9.549 (95%, CI 6.864-13.285), with no detectable difference across different stressors, doses, and CR criteria (Figure).
Conclusion: The presence of CR during SE with either dobutamine or exercise is associated to greater chances of functional recovery after CRT. This parameter is now ready to be tested in a prospective multicenter trial to select patients more likely to benefit from CRT
Author Disclosures: Q. Ciampi: None. C. Carpeggiani: None. C. Michelassi: None. B. villari: None. E. Picano: None.
- © 2016 by American Heart Association, Inc.