Abstract
The global aging population has led to a growing prevalence of heart failure (HF), signaling a new era often referred to as the HF pandemic. HF is strongly associated with both ischemic and hemorrhagic stroke, contributing to the global burden of cerebrovascular disease. In particular, ischemic stroke is frequently observed in patients with HF due to the common coexistence of atrial fibrillation (AF). Given that stroke and HF are both major causes of morbidity and mortality worldwide, a comprehensive understanding of their interrelationship is essential. In 2021, HF was redefined as "a clinical syndrome characterized by symptoms and signs resulting from structural and/or functional cardiac abnormalities, accompanied by current or prior evidence of elevated natriuretic peptides and/or objective findings of pulmonary or systemic congestion," and it is now classified according to ejection fraction. Among these categories, heart failure with reduced ejection fraction (HFrEF) has been the focus of extensive research, and its treatment has significantly advanced with the development of the so-called "Fantastic Four" pharmacologic therapies. A deeper understanding of the pathophysiological interplay between HF and stroke is crucial to inform future research and improve clinical practice. This review aims to comprehensively summarize the pathophysiological and clinical interrelationship between heart failure and stroke and to provide updated insights for future research and clinical management.