Post-acute and long-term cardiovascular effects following dengue infection: A systematic review protocol

Background and Aim: Dengue is a major arboviral disease in tropical and subtropical regions, traditionally regarded as an acute, self-limiting illness. However, emerging evidence suggests that its consequences may extend beyond the acute phase, especially involving the cardiovascular system. Reported manifestations include major adverse cardiovascular events, arrhythmias, thromboembolic complications, subclinical myocardial dysfunction, endothelial dysfunction, and vascular changes. Evidence remains fragmented due to variation in study designs, population characteristics, outcome definitions, and follow-up durations. This systematic review aims to appraise and synthesise evidence on post-acute and long-term cardiovascular outcomes following dengue infection, including their spectrum, comparative risk, and determinants. Methods and analysis: This protocol outlines a systematic review of cardiovascular outcomes in the post-acute and long-term phases of dengue infection. Human studies of any age group will be included if they report cardiovascular outcomes at least 4 weeks after acute dengue illness. Laboratory-confirmed dengue will be prioritised for primary comparative synthesis; clinically diagnosed dengue will contribute to descriptive synthesis and, where appropriate, subgroup or sensitivity analyses. Studies using cohort, case-control, cross-sectional, or case-series designs will be eligible. Comparative studies with dengue-negative or clearly defined reference controls will estimate effects where available, while non-comparative follow-up studies will contribute to descriptive synthesis. Outcomes will include major clinical cardiovascular events, including stroke or transient ischaemic attacks, subclinical cardiac or vascular abnormalities, and cardiovascular-related biomarkers. Searches will be conducted in PubMed/MEDLINE, Scopus, Cochrane Library, CINAHL, ScienceDirect, ProQuest, and Google Scholar. Two reviewers will independently perform screening, data extraction, and risk-of-bias and critical appraisal assessments. Evidence will be synthesized narratively; where comparable, random-effects meta-analysis and Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessment will be conducted. PROSPERO registration: CRD420261354181. Discussion: This review will summarize post-dengue cardiovascular sequelae and identify evidence gaps. Findings may clarify post-dengue cardiovascular risk and inform future research, clinical follow-up, and public health planning in dengue-endemic settings.