Clinical Presentations and Outcomes in Patients Presenting With Acute Cardiac Events and Right Bundle Branch Block

Abstract

We conducted a retrospective analysis of 50 974 patients admitted with acute cardiac events with and without right bundle branch block (RBBB) over 23 years. Compared to non-RBBB, patients with RBBB (n = 386; 0.8%) were 3 years older ( P = .001), more likely to present with breathlessness rather than chest pain ( P = .001), and had more diabetes mellitus ( P = .001). Patients with RBBB had significantly higher cardiac enzymes ( P = .001); however, there were no significant differences in the presentation with ST-segment elevation myocardial infarction (24.6% vs 22.2%), non-ST-segment elevation myocardial infarction (23.7% vs 22.4%), and unstable angina (51.7% vs 55.4%). Patients with RBBB were more likely to have congestive heart failure (CHF; 9.6% vs 3.2%, P = .001), cardiogenic shock (10.6% vs 1.7%, P = .001), and ventricular tachyarrhythmias (7.3% vs 2.2%, P = .001). Left ventricular ejection fraction and hospital length of stay were comparable between the groups. All-cause mortality was 5 times greater in patients with RBBB (21% vs 4.2%, P = .001). Right bundle branch block was independent predictor of mortality (adjusted odd ratio 5.14; 95% confidence interval: 3.90-6.70). Subanalysis comparing normal QRS, RBBB, and left BBB showed that RBBB was associated with the worst outcomes except for CHF. Although RBBB presents in only about 1% of patients with cardiac disease, it was found to be an independent predictor of hospital mortality.

ECG patterns of successful permanent left bundle branch area pacing in bradycardia patients with typical bundle branch block

“…21 In fact, RBBB induced RV dysfunction might be insidious and easily be neglected unless acute RV dysfunction occurs. 25 However, our study could not indicate that the correction of RBBB may improve RV function because only a slightly improved RV synchrony instead of RVEF was observed. In addition, the resolution of bradycardia might also cause the improvements of cardiac function 26 additional to pacing His-Purkinje system, the cardiac function benefits from LBBAP in bradycardia patients should be further studied by comparing with conventional pacing.…”

“…When compared with patients with narrow QRSd, some patients with RBBB showed enlarged RV end diastolic/systolic ventricular index and reduced RVEF 21 . In fact, RBBB induced RV dysfunction might be insidious and easily be neglected unless acute RV dysfunction occurs 25 . However, our study could not indicate that the correction of RBBB may improve RV function because only a slightly improved RV synchrony instead of RVEF was observed.…”

Microcirculatory dysfunction in patients with acute anterior myocardial infarction combined with new complete right bundle branch block

“…These ndings imply that CRBBB patients may suffer larger infarct sizes and a more robust in ammatory response, which could lead to hemodynamic instability and renal and liver dysfunction. Notably, some studies suggest that newonset CRBBB may present with different clinical manifestations, such as increased dyspnea [23] rather than chest pain. Moreover, our ndings indicate that the prolonged time from FMC2W in the new CRBBB group may correlate with more severe cardiac dysfunction and microcirculatory dysfunction in patients with acute anterior STEMI and new CRBBB.…”

New permanent bundle-branch block and long-term prognosis of patients with new onset ST-elevation myocardial infarction who underwent percutaneous coronary intervention

“…Our data are consistent with the guidelines that emphasize the importance of new LBBB in clinic practice, particularly in patients with successful revascularization ( Borja et al, 2018 ). However, the predictive efficacy of RBBB in ACS remains to be determined ( Antman Elliott et al, 2004 ; Mozid Abdul et al, 2015 ; Chan et al, 2016 ; Alkindi et al, 2020 ; Paul et al, 2020 ). The inconsistency among previous studies might be caused by the different criteria for patient enrollment and study endpoints.…”