Outcomes of Preprocedural Pulmonary Hypertension on All-Cause and Cardiac Mortality in Patients Undergoing Transcatheter Aortic Valve Implantation: A Systematic Review

Patients with symptomatic aortic stenosis (AS) commonly have an associated finding of pulmonary hypertension (PH), and it has been previously shown to have increased morbidity and mortality following surgical aortic valve repair (SAVR) as well as transcatheter aortic valve implantation (TAVI). There are no guidelines stating the cut-off point for PH at which the patient can safely undergo TAVI with benefits outweighing the risks. This is partly due to the lack of uniformity in the PH definition used in various studies. This systematic review sought to study the effect of preprocedural pulmonary hypertension on early and late all-cause and cardiac mortality in patients undergoing TAVI. We performed a systematic review of studies comparing patients with AS undergoing TAVI having PH. The review was undertaken as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles were identified from PubMed, Pubmed Central (PMC), Cochrane, and Medline on January 10, 2022, for literature published until January 10, 2022. MeSH strategy was used on PubMed to search the literature, and filters were applied to search only Observational Studies, randomized controlled trials (RCT), and meta-analysis. A total of 170 unique articles were identified and screened. Of the 33 full-text articles that were reviewed, 18 articles, including duplicates, were excluded. Fifteen articles fulfilled the selection criteria and were included in this review. The study design included two meta-analyses, one randomized control trial, one prospective cohort study, and 11 retrospective cohort studies. The studies involved a total of approximately 30,000 patients. The observational studies in our review were of good to fair quality, the RCT had a low to moderate bias, and the meta-analysis was of moderate quality. Baseline PH and persistence of PH post-TAVI are strongly associated with all-cause and cardiac mortality. Few studies have shown that a decrease in post-TAVI PH carries mortality benefits. Therefore, efforts should be made to identify mechanisms of persistent PH post-TAVI and whether interventions to reduce PH pre-TAVI will have any clinical implications or not by conducting RCT.