Clinical implication of right bundle branch block in hospitalized patients with acute heart failure: Data from the Korean Heart Failure (KorHF) Registry

Prevalence, Related Factors and Association of Left Bundle Branch Block With Prognosis in Patients With Acute Heart Failure: a Simultaneous Analysis in 3 Independent Cohorts

OBJECTIVES

To determine the prevalence, characteristics and association with prognosis of left bundle branch block (LBBB) in 3 different cohorts of patients with acute heart failure (AHF).

METHODS AND RESULTS

We retrospectively analyzed 12,950 patients with AHF who were included in the EAHFE (Epidemiology Acute Heart Failure Emergency), RICA (National Heart Failure Registry of the Spanish Internal Medicine Society), and BASEL-V (Basics in Acute Shortness of Breath Evaluation of Switzerland) registries. We independently analyzed the relationship between baseline and clinical characteristics and the presence of LBBB and the potential association of LBBB with 1-year all-cause mortality and a 90-day postdischarge combined endpoint (Emergency Department reconsultation, hospitalization or death). The prevalence of LBBB was 13.5% (95% confidence interval: 12.9%-14.0%). In all registries, patients with LBBB more commonly had coronary artery disease and previous episodes of AHF, were taking chronic spironolactone treatment, had lower left ventricular ejection fraction and systolic blood pressure values and higher NT-proBNP levels. There were no differences in risk for patients with LBBB in any cohort, with adjusted hazard ratios (95% confidence interval) for 1-year mortality in EAHFE/RICA/BASEL-V cohorts of 1.02 (0.89-1.17), 1.15 (0.95-1.38) and 1.32 (0.94-1.86), respectively, and for 90-day postdischarge combined endpoint of 1.00 (0.88-1.14), 1.14 (0.92-1.40) and 1.26 (0.84-1.89). These results were consistent in sensitivity analyses.

CONCLUSIONS

Less than 20% of patients with AHF present LBBB, which is consistently associated with cardiovascular comorbidities, reduced left ventricular ejection fraction and more severe decompensations. Nonetheless, after taking these factors into account, LBBB in patients with AHF is not associated with worse outcomes.

Prognostic Implication of Ventricular Conduction Disturbance Pattern in Hospitalized Patients with Acute Heart Failure Syndrome

Background and Objectives

Conflicting data exist regarding the prognostic implication of ventricular conduction disturbance pattern in patients with heart failure (HF). This study investigated the prognostic impact of ventricular conduction pattern in hospitalized patients with acute HF.

Methods

Data from the Korean Acute Heart Failure registry were used. Patients were categorized into four groups: narrow QRS (<120 ms), right bundle branch block (RBBB), left bundle branch block (LBBB), and nonspecific intraventricular conduction delay (NICD). The NICD was defined as prolonged QRS (≥120 ms) without typical features of LBBB or RBBB. The primary endpoint was the composite of all-cause mortality or rehospitalization for HF aggravation within 1 year after discharge.

Results

This study included 5,157 patients. The primary endpoint occurred in 39.7% of study population. The LBBB group showed the highest incidence of primary endpoint followed by NICD, RBBB, and narrow QRS groups (52.5% vs. 49.7% vs. 44.4% vs. 37.5%, p<0.001). In a multivariable Cox-proportional hazards regression analysis, LBBB and NICD were associated with 39% and 28% increased risk for primary endpoint (LBBB hazard ratio [HR], 1.392; 95% confidence interval [CI], 1.152–1.681; NICD HR, 1.278; 95% CI, 1.074–1.520) compared with narrow QRS group. The HR of RBBB for the primary endpoint was 1.103 (95% CI, 0.915–1.329).

Conclusions

LBBB and NICD were independently associated with an increased risk of 1-year adverse event in hospitalized patients with HF, whereas the prognostic impacts of RBBB were limited.

Trial Registration

ClinicalTrials.gov Identifier: NCT01389843

Temporal Trends of Hospitalized Patients with Heart Failure in Korea

Heart failure (HF) is an important cardiovascular disease because of its increasing prevalence, significant morbidity, high mortality and rapidly expanding health care costs. The number of HF patients is increasing worldwide and Korea is no exception. Temporal trends of four representative Korean hospitalized HF registries-the Hallym HF study, the Korean Multicenter HF study, the Korean Heart Failure (KorHF) registry and the Korean Acute Heart Failure (KorAHF) registry showed mild survival improvement reflecting overall HF patient care development in Korea despite the increased severity of enrolled patients with higher incidence of multiple comorbidities. Moreover, device therapies such as implantable cardioverter defibrillator and cardiac resynchronization therapy and definitive treatment such as heart transplantation have been increasing in Korea as well. To prevent HF burden increase, it is essential to set up long term effective prevention strategies for better control of ischemic heart disease, hypertension and diabetes, which might be risk factors for HF development. Moreover, proper HF guidelines, performance measures, and performance improvement programs might be necessary to limit HF burden as well.

Ventricular conduction abnormalities as predictors of long-term survival in acute de novo and decompensated chronic heart failure

Aims

Data on the prognostic role of left and right bundle branch blocks (LBBB and RBBB), and nonspecific intraventricular conduction delay (IVCD; QRS ≥ 110 ms, no BBB) in acute heart failure (AHF) are controversial. Our aim was to investigate electrocardiographic predictors of long‐term survival in patients with de novo AHF and acutely decompensated chronic heart failure (ADCHF).

Methods and Results

We analysed the admission electrocardiogram of 982 patients from a multicenter European cohort of AHF with 3.9 years' mean follow‐up. Half (51.5%, n = 506) of the patients had de novo AHF. LBBB, and IVCD were more common in ADCHF than in de novo AHF: 17.2% vs. 8.7% (P < 0.001) and 20.6% vs. 13.2% (P = 0.001), respectively, and RBBB was almost equally common (6.9% and 8.1%; P = 0.5), respectively. Mortality during the follow‐up was higher in patients with RBBB (85.4%) and IVCD (73.7%) compared with patients with normal ventricular conduction (57.0%); P < 0.001 for both. The impact of RBBB on prognosis was prominent in de novo AHF (adjusted HR 1.93, 1.03–3.60; P = 0.04), and IVCD independently predicted death in ADCHF (adjusted HR 1.79, 1.28–2.52; P = 0.001). Both findings were pronounced in patients with reduced ejection fraction. LBBB showed no association with increased mortality in either of the subgroups. The main results were confirmed in a validation cohort of 1511 AHF patients with 5.9 years' mean follow‐up.

Conclusions

Conduction abnormalities predict long‐term survival differently in de novo AHF and ADCHF. RBBB predicts mortality in de novo AHF, and IVCD in ADCHF. LBBB has no additive predictive value in AHF requiring hospitalization.

Prognostic Factors in Hospitalization for Heart Failure in Asia

The hospitalized heart failure (HF) population is becoming a significant economic burden to Asian countries because of the growing elderly population, increased prevalence of HF, and recurrent rehospitalization. A targeted treatment strategy is needed with prognostic factors that can reduce mortality or rehospitalization after discharge. The accepted prognostic factors include age, low systolic blood pressure, ischemic heart disease, reduced left ventricular function, hyponatremia, and renal dysfunction. Prognostic factors for clinical outcomes in hospitalized patients with HF may be different in Asian people. Further research leading to better understanding of the characteristics of Asian patients hospitalized with HF is warranted.

Hemoconcentration is a good prognostic predictor for clinical outcomes in acute heart failure: data from the Korean Heart Failure (KorHF) Registry

BACKGROUND

Hemoconcentration is a surrogate marker of effective decongestion and diuresis therapy. Recently, hemoconcentration has been associated with decreased mortality and rehospitalization in heart failure (HF) patients. However, the prognostic power of hemoconcentration in a large sample-sized HF cohort was limited until now.

METHODS AND RESULTS

We analyzed data from hospitalized patients with acute heart failure (AHF) that were enrolled in the Korean Heart Failure Registry(n=2,357). The primary end point was a composite of all-cause mortality and HF rehospitalization during the follow-up period (median=347, interquartile range=78-744 days).Hemoconcentration, defined as an increased hemoglobin level between admission and discharge, was presented in 1,016 AHF patients (43.1%). In multivariable logistic regression, hemoglobin, total cholesterol, and serum glucose levels at admission, and ischemic HF, were significant determinants for hemoconcentration occurrence. The Kaplan-Meier curve showed that event-free survival was significantly higher in the hemoconcentration group compared to the non-hemoconcentration group (65.1% vs. 58.1%, log rank p<0.001). In multiple Cox proportional hazard analysis, hemoconcentration was an independent predictor of the primary end point after adjusting for other HF risk factors (hazard ratio=0.671, 95% confidence interval=0.564-0.798, p<0.001).

CONCLUSIONS

Hemoconcentration during hospitalization was a prognostic marker of fewer clinical events in the AHF cohort. Therefore, this novel surrogate marker will help in the risk stratification of AHF patients.

Differential clinical characteristics and prognosis of intraventricular conduction defects in patients with chronic heart failure

AIMS

Intraventricular conduction defects (IVCDs) can impair prognosis of heart failure (HF), but their specific impact is not well established. This study aimed to analyse the clinical profile and outcomes of HF patients with LBBB, right bundle branch block (RBBB), left anterior fascicular block (LAFB), and no IVCDs.

METHODS AND RESULTS

Clinical variables and outcomes after a median follow-up of 21 months were analysed in 1762 patients with chronic HF and LBBB (n = 532), RBBB (n = 134), LAFB (n = 154), and no IVCDs (n = 942). LBBB was associated with more marked LV dilation, depressed LVEF, and mitral valve regurgitation. Patients with RBBB presented overt signs of congestive HF and depressed right ventricular motion. The LAFB group presented intermediate clinical characteristics, and patients with no IVCDs were more often women with less enlarged left ventricles and less depressed LVEF. Death occurred in 332 patients (interannual mortality = 10.8%): cardiovascular in 257, extravascular in 61, and of unknown origin in 14 patients. Cardiac death occurred in 230 (pump failure in 171 and sudden death in 59). An adjusted Cox model showed higher risk of cardiac death and pump failure death in the LBBB and RBBB than in the LAFB and the no IVCD groups.

CONCLUSION

LBBB and RBBB are associated with different clinical profiles and both are independent predictors of increased risk of cardiac death in patients with HF. A more favourable prognosis was observed in patients with LAFB and in those free of IVCDs. Further research in HF patients with RBBB is warranted.