Abstract / Summary
Cardiac cephalalgia is an uncommon manifestation of myocardial ischemia whose clinical phenotype and concordance with current International Classification of Headache Disorders 3rd edition (ICHD-3) diagnostic criteria remain poorly defined. We aimed to characterize the reported clinical phenotype, assess the consistency of objective evidence linking headache to myocardial ischemia, and evaluate concordance with the individual and overall ICHD-3 diagnostic criteria. We performed a systematic review and individual patient data meta-analysis of published case reports and case series. Individual-level demographic, clinical, diagnostic, angiographic, therapeutic, and outcome data were reconstructed from eligible patients. Pooled proportions with 95% confidence intervals (95% CI) were estimated for major clinical features and diagnostic criteria. Twenty-five studies comprising 32 patients were included. Among the 30 patients with reported headache intensity, 26 had moderate-to-severe headache (86.7%; 95% CI: 70.3–94.7). In contrast, accompanying cardiac symptoms were reported in 15 of 31 evaluable patients (48.4%; 95% CI: 31.8–65.4), indicating phenotypic heterogeneity. Among evaluable patients, ischemic electrocardiographic abnormalities were reported in 92.6% (95% CI: 76.6–97.9), and headache resolution after treatment of myocardial ischemia was reported in 96.0% (95% CI: 80.5–99.3). Complete fulfillment of evaluable ICHD-3 criteria occurred in 76.0% of patients, with discordance arising predominantly from phenotypic rather than causal diagnostic criteria. Published cases showed substantial heterogeneity in headache presentation despite frequently reported temporal and therapeutic relationships with myocardial ischemia. Prospective studies using standardized headache assessments are needed to determine whether refinement of the phenotypic components of the ICHD-3 diagnostic framework is warranted. Systematic review registration: CRD420251244645. Not applicable.