Right-to-left shunt, atrial septal aneurysm and thrombophilia in patients with cryptogenic stroke or TIA vs. those with venous thrombo-embolism

Whether intracardiac right-to-left shunt (RLS) is an independent risk factor for cerebrovascular accidents is disputed. In patients with RLS, venous thrombo-embolism (VTE) may predispose to paradoxical embolic events, among which stroke and transient ischemic attack (TIA). Whether genetic or acquired thrombophilia is associated with RLS is unclear. Thus, we compared prevalences of intra- and extracardiac intrapulmonary RLS and of atrial septal aneurysm (ASA) between 29 nondiabetic patients with cryptogenic stroke (n = 17) or TIA (n = 12) and 19 patients with VTE but without history of stroke/TIA, or autoimmune systemic disease or migraine. Carotid atherosclerosis was excluded in all patients. RLS and ASA were also evaluated in 30 healthy volunteers. We found that intracardiac RLS (31%) and ASA (21%) were detected in stroke/TIA patients and not in our selected VTE patients (both p < 0.05); however, those prevalences were comparable to those detected in our controls (20% intracardiac RLS, 7% ASA, respectively, both p = NS). Within patients, thrombophilia was not associated with intracardiac RLS, but tended to be associated with ASA (83% in those with vs. 43% in those without ASA, p = 0.08). In conclusions, intracardiac RLS may have a role in selected populations in the frame the multi-factorial pathogenesis of stroke/TIA of embolic origin. ASA appears to be an independent risk factor for stroke/TIA with possible interaction with thrombophilia.