An IVUS study of May-Thurner syndrome in patients with cryptogenic stroke and patent foramen ovale

Background: We have previously documented the incidence of MayThurner Syndrome (MTS) in patients with cryptogenic stroke and patent foramen ovale (PFO). We prospectively performed intravascular ultrasound (IVUS) in a cohort of 16 patients undergoing PFO closure in the context of a cryptogenic stroke. Methods: IVUS was performed of the left common iliac vein (CIV) in all patients with documented MTS by magnetic resonance venography using an 8F, 40-MHz transducer (Boston Scientific Corporation, Natick, MA, USA). The transducer was positioned distally in the inferior vena cava and systematically pulled back through the left CIV into the sheath. Studies were recorded and analyzed offline. Results: The patients were predominantly female (88%) with a mean age of 40±12 years. The group represented a low cardiovascular risk group with hypertension (12%), hypercholesterolemia (11%), smokers (27%), and diabetes (17%). All PFOs demonstrated right-to-left shunting on transesophageal echocardiography. Atrial septal aneurysms were present in 16% and hypermobile atrial septae in 17% of patients. IVUS demonstrated N75% lumen area stenosis from the adjacent right common iliac artery in all studied vessels. Intimal venous spurs were observed in two patients, venous stasis with rouleaux formation was observed in 10 patients but no evidence of deep venous thromboses was evident in these vessels. Conclusion: IVUS is a safe and reliable invasive tool for the study of MTS in the context of PFO and cryptogenic stroke. This study further highlights the importance of the association of MTS and PFO in the context of cryptogenic stroke.