Coronary Microvascular Dysfunction: Diagnostic Challenges And Emerging Therapies

Coronary microvascular dysfunction (CMD) represents a major paradigm shift in understanding ischemic heart disease, particularly among patients—often women—with angina and no obstructive coronary artery disease. This chapter explores CMD’s complex pathophysiology, highlighting the roles of endothelial dysfunction, microvascular remodeling, and vasospasm. It discusses the diagnostic challenges posed by the “normal” angiogram and summarizes the emerging diagnostic tools including invasive coronary function testing, PET, CMR, echocardiography, and CT perfusion imaging that now allow direct assessment of microvascular function. Therapeutic strategies are reviewed in detail, emphasizing risk factor control, ACE inhibitors, statins, and anti-anginal agents such as beta-blockers, calcium channel blockers, and ranolazine, alongside novel and investigational therapies (e.g., endothelin antagonists, Rho-kinase inhibitors). The chapter also addresses sex-specific aspects, noting CMD’s high prevalence and distinct clinical features in women. It concludes with insights into ongoing clinical trials (WARRIOR, PRIZE) and future research directions toward precision medicine in CMD.