Elnady, Mohamed

ABSTRACT Background In patients with atrial fibrillation (AF) and heart failure with reduced ejection fraction (HFrEF), atrioventricular node ablation (AVNA) and permanent pacing are often pursued when rhythm control is not pursued. Biventricular pacing (BiVP) has demonstrated benefits over right ventricular pacing, while conduction system pacing (CSP) has emerged as an alternative. However, evidence directly comparing CSP with BiVP in this high‐risk population remains inconsistent. Objective To compare CSP versus BiVP in patients with AF and HFrEF undergoing AVNA, focusing on cardiac function, clinical outcomes, and procedural metrics. Methods Following PRISMA guidelines, we searched PubMed, Scopus, and Web of Science through February 2026 for studies comparing CSP and BiVP in adults with AF and HFrEF undergoing AVNA. Outcomes included all‐cause mortality, heart failure hospitalization (HFH), changes in left ventricular ejection fraction (LVEF), QRS duration, New York Heart Association (NYHA) class, pacing threshold, procedure duration, and fluoroscopy duration. A random‐effects model was used to pool mean differences (MDs) or risk ratios (RRs) with 95% confidence intervals (CIs). Results Six studies (one randomized crossover trial and five observational studies; N = 766 patients: CSP = 356, BiVP = 410) were included. All‐cause mortality was significantly reduced in favor of CSP (RR 0.64 [CI: 0.44 to 0.94], p = 0.02, I 2 = 0%). There was also a trend towards lower HFH, but it marginally missed statistical significance (RR 0.77 [CI: 0.58 to 1.03], p = 0.08; I 2 = 0%). Additionally, CSP decreased NYHA class (MD ‐0.64 [CI: −1.18 to −0.10], p = 0.02; I 2 = 85%) and significantly reduced QRS duration (MD −33.56 ms [CI: −52.36 to −14.76], p = 0.0005; I 2 = 97%). LVEF improvement did not significantly differ between groups (MD 4.51% [95% CI: −1.50 to 10.52], p = 0.14; I 2 = 98%). Procedure duration and fluoroscopy times did not show statistically significant difference between the two groups (MD −11.54 min [CI: −50.05 to 26.97], p = 0.56, I 2 = 96%), and (MD −5.75 min [CI: −13.13 to 1.63], p = 0.13, I 2 = 88%), respectively. Overall pacing thresholds did not significantly differ between CSP and BiVP; however, modality‐specific subgroup analysis showed comparable thresholds between HBP and BiVP, whereas LBBP was associated with significantly lower pacing thresholds than BiVP. Conclusions Among patients with AF and HFrEF undergoing AVNA, CSP may offer symptomatic and electrocardiographic advantages over BiVP, with a possible signal toward improved major clinical outcomes that requires confirmation in larger randomized studies.

ABSTRACT Observational studies comparing Impella and venoarterial extracorporeal membrane oxygenation (VA‐ECMO) in cardiogenic shock have reported inconsistent findings. We performed an updated systematic review and meta‐analysis, with exploratory matched‐cohort analyses where directly reportable propensity score–matched event‐level data were available. We searched PubMed, Scopus, Web of Science, and the Cochrane Library from inception through March 2026 for observational studies comparing Impella versus VA‐ECMO in adult patients with cardiogenic shock. The primary outcome was in‐hospital mortality. Secondary outcomes included all‐cause mortality, ICU outcomes, access site bleeding requiring transfusion, peripheral vascular complications, renal outcomes, and stroke. Random‐effects models using restricted maximum likelihood were applied. Fifteen observational studies including 22,618 patients were analyzed. In the primary crude analysis, Impella was not associated with a statistically significant difference in in‐hospital mortality (RR 0.84, 95% CI 0.66−1.07; p = 0.15) with substantial heterogeneity ( I ² = 92.9%). However, leave‐one‐out analysis identified an influential registry study; its exclusion markedly reduced heterogeneity and favored Impella ( p < 0.01). In exploratory propensity score‐matched analysis, Impella was also associated with lower in‐hospital mortality (RR 0.69, 95% CI 0.56−0.85, p < 0.01). Thirty‐day and 6‐month all‐cause mortality were neutral, whereas 12‐month mortality modestly favored Impella ( p = 0.048). Sensitivity analyses similarly resolved heterogeneity and favored Impella for selected secondary outcomes, including 6‐month mortality, acute kidney injury, and ischemic stroke. ICU mortality was neutral, while ICU length of stay was shorter with Impella ( p = 0.01). Impella was also associated with lower access site bleeding requiring transfusion ( p < 0.01), peripheral vascular complications ( p < 0.01), and hemorrhagic stroke ( p < 0.01). In this updated meta‐analysis of observational studies, the primary crude analysis of in‐hospital mortality was neutral overall but highly heterogeneous, whereas sensitivity and exploratory matched‐cohort analyses showed a more consistent association favoring Impella. Impella was also associated with lower bleeding and vascular complications and shorter ICU length of stay, although several outcomes remained sensitive to study‐level influence. These findings should be interpreted cautiously given the observational design, predominance of serious risk of bias, and strong potential for confounding by indication.