Left bundle branch block may be due to conduction system degeneration or a reflection of myocardial pathology. Left bundle branch block may also develop following aortic valve disease or cardiac procedures. Patients with heart failure with reduced ejection fraction and left bundle branch block may respond positively to cardiac resynchronization therapy. Lead placement via the coronary sinus is the mainstay approach of cardiac resynchronization therapy. However, other options, including physiological pacing, are being explored. In this review, we summarize the salient pathophysiologic and clinical aspects of left bundle branch block, as well as current and future strategies for management.

Ten case reports of disseminated Mycobacterium chimaera infections associated with cardiovascular surgery were published from Europe. We report 3 cases of disseminated M chimaera infections with histories of aortic graft and/or valvular surgery within the United States. Two of 3 patients demonstrated ocular involvement, a potentially important clinical finding.

The prevention of stroke in patients with atrial fibrillation (AF) and cancer is challenging because patients are at increased bleeding and thrombotic risk. The authors sought to assess left atrial appendage occlusion (LAAO) as a safe and effective strategy for reducing stroke at no increased bleeding risk in cancer patients with AF. We reviewed patients with nonvalvular AF who underwent LAAO at Mayo Clinic sites from 2017 to 2020 and identified those who had undergone prior or current treatment for cancer. We compared the incidence of stroke, bleeding, device complications, and death with a control group who underwent LAAO without malignancy. Fifty-five patients were included; 44 (80.0%) were male, and the mean age was 79.0 ± 6.1 years. The median CHA₂Ds₂-VASc score was 5 (Q1-Q3: 4-6), with 47 (85.5%) having a prior bleeding event. Over the first year, ischemic stroke occurred in 1 (1.4%) patient, bleeding complications in 5 (10.7%) patients, and death in 3 (6.5%) patients. Compared with controls who underwent LAAO without cancer, there was no significant difference in ischemic stroke (HR: 0.44; 95% CI: 0.10-1.97; P = 0.28), bleeding complication (HR: 0.71; 95% CI: 0.28-1.86; P = 0.19), or death (HR: 1.39; 95% CI: 0.73-2.64; P = 0.32). Within our cohort, LAAO in cancer patients was achieved with good procedural success and offered a reduction in stroke at no increased bleeding risk similar to noncancer patients.

Background: The epidemiology of ventricular arrhythmias (VAs) in patients with advanced heart failure (HF) is not well defined. Methods and Results: Residents of Olmsted County, Minnesota, with advanced HF from 2007 to 2017 were identified using the 2018 European Society of Cardiology criteria. Billing codes were used to capture VAs; severe VAs requiring emergency care were defined as events associated with emergency department visits or hospitalizations. The cumulative incidence of VAs postadvanced HF was estimated with the Kaplan–Meier method. Multivariable Cox analyses were used to determine the following: (1) Predictors of severe VAs postadvanced HF; and (2) Impact of severe VAs on mortality. Of 936 patients with advanced HF, 261 (27.9%) had a history of VA. The 1‐year cumulative incidence of severe VAs postadvanced HF was 5.4%. Prior VAs (hazard ratio [HR] 2.22 [95% CI, 1.26–3.89], P =0.006) and left ventricular ejection fraction <40% (HR, 3.79 [95% CI, 1.72–8.39], P <0.001) were independently associated with increased severe VA risk postadvanced HF. New‐onset severe VAs were associated with increased mortality (HR, 4.41 [95% CI, 2.80–6.94]; P <0.001), whereas severe VAs in patients with prior VAs had no significant association with mortality risk (HR, 1.08 [95% CI, 0.65–1.78]; P =0.77). Severe VAs were associated with increased mortality in patients without implantable cardioverter defibrillators (HR, 4.89 [95% CI, 2.89–8.26]; P <0.001), but not in patients with implantable cardioverter defibrillators (HR, 1.42 [95% CI, 0.92–2.19]; P =0.11). Conclusions: Patients with left ventricular ejection fraction <40% and prior VAs have increased risk of severe VA postadvanced HF. New‐onset severe VAs or severe VAs without implantable cardioverter defibrillators postadvanced HF are associated with increased mortality.