Valve-specific structural vulnerability in infective endocarditis: a narrative review of surgical complexity and...

Infective endocarditis (IE) carries in-hospital mortality of 15-20% and 1-year mortality approaching 40%, with surgery required in 40-50% of cases. IE is not uniformly distributed across cardiac valves aortic 30-45%, mitral 25-30%, tricuspid 5-10%, pulmonary < 2%, PVE 10-30% and this distribution reflects valve-specific anatomical determinants governing surgical complexity and outcomes. Despite the 2023 ESC Guidelines, a unified structural framework linking anatomical vulnerability to surgical decision-making remains absent.

To propose a valve-specific structural vulnerability framework and examine its implications for surgical complexity, perioperative outcomes, and re-surgery risk across all cardiac valve types.

A narrative review of peer-reviewed literature (2015-2025) was conducted across PubMed, Scopus, and MEDLINE. Systematic reviews, meta-analyses, multicentre registries, and guideline documents were synthesised narratively.

A structural vulnerability gradient (prosthetic valves > aortic > mitral > tricuspid > pulmonary) is proposed as a conceptual model of valve-specific disease behaviour. Aortic IE carries maximal vulnerability through peri-annular extension, 30-40% of cases, requiring radical root reconstruction with elevated operative mortality. Mitral IE exhibits conditional vulnerability; repair yields superior outcomes over replacement. Tricuspid IE is predominantly IVDU-associated with comparatively lower operative mortality. PVE carries the highest operative risk, with prolonged operative times and significant reoperation rates.

IE is best understood as a valve- and substrate-specific disease in which anatomical determinants drive surgical complexity and clinical prognosis. This proposed vulnerability hierarchy may enable preoperative risk stratification, inform valve-specific surgical planning, and provide a mechanistic framework for understanding differential outcomes across valve types. Prospective outcome registries and standardised complexity metrics are needed to validate and refine this conceptual model.