Cardiovascular Outcomes and Acute Human Metapneumovirus Infection in Adults: A Systematic Literature Review.

OBJECTIVES: Acute respiratory viral infections, including influenza, RSV, and SARS-CoV-2, are well-recognized as being associated with cardiovascular events (CVEs). In contrast, the cardiovascular impact of human metapneumovirus (HMPV) remains poorly characterized. We aimed to describe the prevalence of pre-existing cardiovascular diseases (CVDs) and the incidence of acute CVEs in adults with laboratory-confirmed HMPV infection. METHODS: PRISMA-guided systematic literature review of MEDLINE, Embase, and Google Scholar (Jan.-2000/Sept.-2025). Observational studies and clinical trials reporting pre-existing CVDs and/or CVEs in adults (≥18 years) were included. RESULTS: Eighteen studies met the inclusion criteria, of which nine underwent critical appraisal. Most involved hospitalized older adults. Pre-existing CVD was reported in 10%-80% of HMPV-infected patients, with chronic heart failure and coronary artery disease being the most common conditions. Acute CVEs, particularly heart failure exacerbations, occurred in 5%-25% of hospitalized patients. Underlying CVD was consistently linked to increased severity of HMPV illness, including higher rates of ICU admission and mortality. CONCLUSIONS: Acute HMPV infection frequently occurs in adults with pre-existing CVD and may be associated with CVEs in older hospitalized populations. However, evidence remains limited and largely observational. These findings highlight the need to increase awareness of the potential CV complications associated with HMPV infection. TRIAL REGISTRATION: PROSPERO [CRD420251164583].