O'Nunain, SeanAleshaiwy, Talal Adel2025-12-292025https://hdl.handle.net/20.500.14154/77725Methods: PubMed, EMBASE, MEDLINE, CINAHL, the Cochrane Library, and Google Scholar were searched for studies published between 2014 and 31 December 2024 that directly compared LBBAP with BiVP. Only English-language randomised and observational studies were included. Screening and data extraction followed predefined criteria. Primary outcomes were change in left ventricular ejection fraction (LVEF), QRS duration, New York Heart Association (NYHA) class improvement, heart failure hospitalisation (HFH), and mortality. Secondary outcomes were pacing thresholds, lead impedance, fluoroscopy time, and procedural complications. Risk of bias was assessed using the cochrane risk-of-bias tool for randomised trials (RoB 2) and the Newcastle–Ottawa Scale (NOS) for observational studies. Random-effects meta-analyses were performed for continuous outcomes (LVEF, QRS duration, NYHA), expressed as standardised mean differences (SMDs) with 95% confidence intervals (CIs); heterogeneity was assessed with I². For HFH and mortality, the studies differed in effect measures, follow-up length, and statistical adjustment, so these outcomes were not pooled. Instead, event rates from each study are shown as bar charts, with significance indicated according to the p-values reported by the original authors.81enheart failureleft bundle branch area pacingcardiac resynchronizationleft bundle branch blockThesis