The prognostic value of peak oxygen uptake in obstructive hypertrophic cardiomyopathy: A literature review to inform economic model development.

Aims: Patients with obstructive hypertrophic cardiomyopathy (oHCM) experience significant clinical burden which is associated with a high economic burden. Peak oxygen uptake (pVO2), measured by cardiopulmonary exercise testing, is used to quantify functional capacity, and has been studied as a primary endpoint in recent clinical trials. This study aimed to gather evidence to consolidate the prognostic value of pVO2 in oHCM and to assess whether it is feasible to predict health outcomes in an economic model based on changes in pVO2. Methods: A targeted literature review was conducted in MEDLINE (via PubMed) and Embase databases to identify evidence on the prognostic value of pVO2 as a surrogate health outcome to support future oHCM economic model development. Following screening, study characteristics, population characteristics and pVO2 prognostic association data were extracted. Results: A total of 4,687 studies were identified. 3,531 and 538 studies underwent title/abstract and full-text screening, respectively, of which 151 were included and 9 of these were in hypertrophic cardiomyopathy (HCM); only 3 studies focused on oHCM. The 9 HCM studies consisted of 1 systematic literature review and 8 primary studies reporting on 27 potentially predictive relationships from a pVO2-based metric with clinical outcomes including all-cause mortality, cardiovascular mortality, sudden cardiac death, transplant, paroxysmal and permanent atrial fibrillation. pVO2 was described as a predictor of single and composite endpoints, in 3 and 6 studies respectively, with 1 study reporting on both. Limitations: This study primarily uses systemic literature review methods but does not qualify as one due to not entailing parallel reviewers during title-abstract and full-text stages of review. Conclusion: The findings of this study suggest pVO2 is predictive of multiple health outcomes, providing rationale to use pVO2 in the development of an economic model.