Table. Stroke etiology based on the TOAST classification—Comparison of young adult with older adult stroke patients.

	Macroangiopathy	Cardioembolic	Microangiopathy	Other definite causes	Cryptogenic
Young adult 18–55 years	8–28%	5–25% PFO with/without ASA (5–20%) Arrhythmias (AF) Endocarditis Valve defects Cardiomyopathy Cardiac valve tumors (myxoma / fibroelastoma)	5–19%	20–30% Dissection (10–25 %) Vasculitis Thrombophilia RCVS/PRES Moyamoya disease Hereditary microangiopathies MELAS/M. Fabry Paraneoplastic disease	25–50%
>55 years	15–20%	25–35% Atrial fibrillation (AF)(20–30%) Myocardial infarct Valve defects Cardiomyopathy	20–25%	<5%	20–35%

AF, atrial fibrillation; ASA, atrial septal aneurysm; MELAS, mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes; PFO, patent foramen ovale; PRES, posterior reversible encephalopathy syndrome; RCVS, reversible cerebral vasoconstriction syndrome; TOAST, Trial of ORG 10172 in Acute Stroke Treatment