Microvascular dysfunction, particularly endothelial dysfunction, is increasingly recognized as a key mechanism underlying various cardiovascular diseases (CVD), including heart failure, ischemic heart disease, atherosclerosis, stroke, dementia, and kidney failure. Chronic low-grade inflammation linked to metabolic syndrome may further drive systemic microvascular impairment. Early detection of these subclinical processes using non-invasive assessments could facilitate timely interventions to prevent disease progression. SCAPIS 2 Spectrum is a prospective observational sub-study of the Swedish Cardiopulmonary Bioimage Study (SCAPIS-2), recruiting approximately 900 subjects aged 60-75 years. The study is organized into five arms-obstructive coronary artery disease (O-CAD), angina with nonobstructive coronary arteries (ANOCA), metabolic syndrome with diabetes, left ventricular systolic dysfunction, and left ventricular diastolic dysfunction-each defined by specific inclusion and exclusion criteria. Participants will undergo a comprehensive microvascular assessment using investigational devices (including Perimed Periflux EPOS, PeriCam MultiFlow, and TCI P4) alongside stress cardiac magnetic resonance imaging (stress-CMR) for cardiac-specific evaluation.