Additive Prognostic Value of Echocardiographic Global Longitudinal and Global Circumferential Strain to Electrocardiographic Criteria in Patients With Heart Failure Undergoing Cardiac Resynchronization Therapy

Abstract

Background-Response to cardiac resynchronization therapy is most favorable in patients with heart failure with QRS duration ≥150 ms and left bundle branch block and less predictable in those with QRS width 120 to 149 ms or non-left bundle branch block. Methods and Results-We studied 205 patients with heart failure referred for cardiac resynchronization therapy with QRS ≥120 ms and ejection fraction ≤35%. We tested the hypothesis that contractile function using speckle-tracking echocardiographic global circumferential strain (GCS) from 2 short-axis views and global longitudinal strain (GLS) from 3 apical views add prognostic value to electrocardiographic criteria. There were 112 patients (55%) with GLS >−9% and 136 patients (66%) with GCS >−9%. During 4 years, 81 patients reached the combined primary end point (death, circulatory support, or transplant) and 120 reached the secondary end point (heart failure hospitalization or death). Both GLS >−9% and GCS >−9% were associated with increased risk of unfavorable events as follows: for the primary end point (hazard ratio=2.91; 95% confidence interval, 1. Methods Patient PopulationThis was a prospective longitudinal study design at a single center. All patients fulfilled current criteria for CRT implant with New York Heart Association (NYHA) class II to IV HF on optimal pharmacological therapy, QRS width ≥120 ms, and LVEF ≤35%. This study was approved by the Institutional Review Board of Biomedical Research, and all patients gave informed consent according to this study protocol. Patients with chronic right ventricular pacing or a failed CRT implant were excluded. The study population included 205 consecutive CRT patients with baseline echocardiography suitable for speckle-tracking analysis, which was 91% of the initial cohort. Ischemic pathogenesis was defined as ≥70% stenosis in ≥1 epicardial coronary vessel on angiography or history of myocardial infarction or revascularization. Baseline LBBB and right bundle branch block (RBBB) morphology were defined using standard criteria. 11 Intraventricular conduction delay was defined as QRS duration ≥120 ms not meeting criteria for either LBBB or RBBB. Intermediate ECG criteria were QRS 120 to 149 ms, regardless of morphology or non-LBBB morphology (RBBB or intraventricular conduction delay). Patients with atrial fibrillation were not included. All patients had a biventricular pacing system implanted with a standard right atrial lead, a right ventricular apical lead, and LV lead positioned through the coronary sinus, targeting the lateral or posterolateral LV free wall. Patients were typically programmed to an atrioventricular interval of 120-130 ms with no ventricular-ventricular pacing offset. These patients did not routinely undergo formal atrioventricular or ventricular-ventricular optimization studies. 12 EchocardiographyAll echocardiographic studies were performed with similar echocardiography systems (Vivid 7; GE Vingmed, Horten, Norway). Routine echocardiography included standard apical views, and basal and mid-L...

The Role of Echocardiography in the Optimization of Cardiac Resynchronization Therapy: Current Evidence and Future Perspectives

“…In an analysis of 313 heart failure patients (non-ischaemic, LBBB) who underwent implantation of a biventricular device, the study showed markedly lower longitudinal strain, suggesting that myocardial dysfunction burden might be the predictor of reverse remodeling in these patients [ 32 , 33 ].…”

Prognostic implications of left ventricular global longitudinal strain in heart failure patients with narrow QRS complex treated with cardiac resynchronization therapy: a subanalysis of the randomized EchoCRT trial

“…19 In a retrospective series 13 of 205 patients treated with CRT (70% with left bundle branch block QRS morphology), LV GLS <9% was associated with higher rates of all-cause mortality, LV assist device implantation and heart transplantation (unadjusted HR 2.91, 95% CI 1.88-4.49, P<0.001). 20 On multivariate analysis, each decrease in LV GLS was associated with 1.11-fold increased risk of the combined endpoint (95% CI 1.1-1.23, P=0.032).…”

More than 10 years of speckle tracking echocardiography: Still a novel technique or a definite tool for clinical practice?

“…Correct diagnosis and identification of patients with heart failure (HF) is fundamental for their following management, even more when LVEF is preserved. [50][51][52][53][54][55][56] STE has been also applied to heart transplantation 57,58 and to LV assist device (LVAD). 59,60…”