Cardiac disease and stroke: will history repeat itself?

Comparison of frequencies of patent foramen ovale and thoracic aortic atherosclerosis in patients with cryptogenic ischemic stroke undergoing transesophageal echocardiography

Studies have shown an association between the presence of a patent foramen ovale (PFO) and cryptogenic stroke (CS) in patients aged <55 years. In addition, protruding atheromatous plaques in the ascending aorta and aortic arch are an independent risk factor for ischemic stroke in patients aged ≥55 years. The aim of this study was to determine the association of CS in the 2 age groups with PFO and with atheromatous plaques in the ascending aorta and in the aortic arch. Transesophageal echocardiograms in 229 patients evaluated for CS were compared to those in 314 patients evaluated for cardiac disease other than PFO with no histories of stroke (the control group). The prevalence of PFO and the presence of complex atheromatous plaques in the ascending aorta and aortic arch were determined in all patients and compared between the CS and control patients in the 2 age groups. The prevalence of PFO was significantly higher in patients with CS than in control patients among those aged <55 years (31 of 114 [27%] vs 24 of 171 [14%], p = 0.006) and those aged ≥55 years (28 of 115 [24%] vs 21 of 143 [15%], p = 0.049). The incidence of atrial septal aneurysm was similar in the 2 groups irrespective of patient age, as was the prevalence of complex atheromatous plaques. Multivariate analysis showed that PFO was independently associated with CS, irrespective of patient age (<55 years: odds ratio 2.4, 95% confidence interval 1.3 to 4.5, p = 0.01; ≥55 years: odds ratio 1.9, 95% confidence interval 1.1 to 3.5, p = 0.03). In conclusion, PFO was significantly associated with CS in younger (aged <55 years) and older (aged ≥55 years) patients. Atrial septal aneurysm and complex atheromas in the ascending aorta and aortic arch do not appear to be associated with CS.

Prevention of Stroke in Patients with Patent Foramen Ovale

Patent foramen ovale is found in 24% of healthy adults and 38% of patients with cryptogenic stroke. This ratio and case reports indicate that patent foramen ovale and stroke are associated, probably because of paradoxical embolism. In healthy people with patent foramen ovale, embolic events are not more frequent than in controls, and therefore no primary prevention is needed. However, once ischaemic events occur, the risk of recurrence is substantial and prevention becomes an issue. Acetylsalicylic acid and warfarin reduce this risk to the same level as in patients without patent foramen ovale. Patent foramen ovale with a coinciding atrial septal aneurysm, spontaneous or large right-to-left shunt, or multiple ischaemic events potentiates the risk of recurrence. Transcatheter device closure has therefore become an intriguing addition to medical treatment, but its therapeutic value still needs to be confirmed by randomised-controlled trials.