Clinical significance of septal deformation patterns in heart failure patients receiving cardiac resynchronization therapy.

AIMS: Specific septal motion related to dyssynchrony is strongly linked to reverse remodelling, in patients with systolic heart failure (HF) receiving cardiac resynchronization therapy (CRT). We aimed to investigate the relationship between septal deformation patterns studied by longitudinal speckle tracking and clinical outcome following CRT. METHODS AND RESULTS: A total of 284 CRT candidates from two centres (HF NYHA classes II-IV, ejection fraction < 35%, QRS ≥ 120 ms) were prospectively included. Longitudinal strain of the septum in the apical four-chamber view determined three patterns of septal contraction. The endpoints were overall mortality, cardiovascular mortality, and hospitalization for HF. Compared with patterns 1 or 2, pattern 3 was associated with an increased risk for both overall and cardiovascular mortality [hazard ratio (HR) = 3.78, 95% confidence interval (CI): 1.85-7.75, P < 0.001 and HR = 3.84, 95% CI: 1.45-10.16, P = 0.007, respectively] and HF hospitalization (HR = 4.41, 95% CI: 2.18-8.90, P < 0.001). Addition of septal patterns to multivariable models, including baseline QRS width and presence of left bundle branch block, improved risk prediction, and discrimination. In patients with intermediate QRS duration (120-150 ms), pattern 3 remained associated with a worse outcome than pattern 1 or 2 (P < 0.05 for all endpoints). CONCLUSION: The identification of septal deformation patterns provides important prognostic information in CRT candidates in addition to ordinary clinical, electrocardiographic, and echocardiographic predictors of outcome in HF patients. This parameter may be particularly useful in patients with intermediate QRS duration in whom the benefit of CRT remains uncertain.

Prognostic importance of postoperative QRS widening in patients with heart failure receiving cardiac resynchronization therapy.

BACKGROUND: Landmark reports have suggested that patients with QRS widening immediately after cardiac resynchronization therapy (CRT) experienced less frequently reverse left ventricular remodeling during follow-up. OBJECTIVE: We sought to investigate the relationship between postoperative QRS widening relative to baseline and mortality in a prospective cohort of heart failure patients receiving CRT. METHODS: A 12-lead electrocardiogram was recorded for 237 heart failure patients (New York Heart Association class II to IV, left ventricular ejection fraction ≤35%, and QRS width ≥120 ms) before and immediately after CRT device implantation. The relationships between QRS widening, all-cause and cardiovascular mortality, and echocardiographic response to CRT were studied. RESULTS: During a median follow-up of 24 months, 39 patients died. Fifty patients (21%) experienced QRS widening after CRT [QRS(+) group]. During follow-up, all-cause mortality was higher in QRS(+) patients than in QRS(-) patients (36-month survival free from death 81% ± 7% vs 64% ± 16%; log rank, P = .029). After adjustment for important prognostic confounders, QRS(+) patients remained associated with an excess overall mortality (adjusted hazard ratio [HR] 2.67; 95% confidence interval 1.07-6.65; P = .035) and cardiovascular mortality (adjusted hazard ratio 3.63; 95% confidence interval 1.13-11.65; P = .03). QRS(+) patients were less frequent responders to CRT than were QRS(-) patients (20 [47%] vs 136 [83%]; P < .0001). CONCLUSION: Postoperative QRS widening relative to baseline after CRT is associated with a considerable increased mortality risk during follow-up. Whether QRS narrowing should be achieved to optimize CRT placement, and thereby increase the rate of CRT responders and improve outcome, deserves further research.

Prognostic value of left ventricular reverse remodeling and performance improvement after cardiac resynchronization therapy: A prospective study.

BACKGROUND: The present study was designed to evaluate the respective value of left ventricular (LV) reverse remodeling (changes in LV end-systolic volume relative to baseline (ΔLVESV)) or LV performance improvement (ΔLV ejection fraction (ΔLVEF) or ΔGlobal longitudinal strain (GLS)) to predict long-term outcome in a prospective cohort of consecutive patients receiving routine cardiac resynchronization therapy (CRT). METHODS: One hundred and seventy heart failure patients (NYHA classes II-IV, LVEF ≤ 35%, QRS width ≥ 120 ms) underwent echocardiography before and 9 months after CRT. The relationships between ΔLVESV, ΔLVEF, ΔGLS and outcome (all-cause mortality and/or CHF hospitalization, overall mortality, cardiovascular mortality, CHF hospitalization) were investigated. RESULTS: During a median follow-up of 32 months, 20 patients died and 27 were hospitalized for heart failure. ΔLVESV, ΔLVEF or ΔGLS were significantly associated with all-cause mortality or CHF hospitalization (adjusted hazard's ratio (HR) per standard deviation 0.58 (0.43-0.77), 0.39 (0.27-0.57) or 0.55 (0.37-0.83) respectively, all p < 0.01) and all other endpoints (all p < 0.01). Patients with ΔLVESV≥15%, ΔLVEF ≥ 10% and ΔGLS ≥ 1% had a reduced risk of mortality or CHF hospitalization (adjusted HR=0.25 (0.12-0.51), p < 0.001, adjusted HR = 0.26 (0.13-0.54), p < 0.001 and adjusted HR 0.38 (0.19-0.75), p = 0.006 respectively). Overall performance of multivariate models was better using ΔLVESV or ΔLVEF compared with ΔGLS. Interobserver agreement was excellent for ΔLVESV (Intraclass correlation coefficient - ICC-0.91) and ΔGLS (ICC 0.90) but modest for ΔLVEF (ICC 0.76) in a sample of 20 patients from the study population. CONCLUSIONS: LV reverse remodeling assessed by ΔLVESV is a strong and reproducible predictor of outcome following CRT. Compared with ΔLVESV, ΔLVEF and ΔGLS have important shortcomings: poorer reproducibility or lower predictive value.