Among the remaining patients only those with cryptogenic stroke are likely to need a TEE. I previously linked to a paper demonstrating a high yield for TEE in finding an indication for warfarin in such patients. Here is a new study documenting similar findings:
Results: 702 consecutive patients (380 male, 383 IS, 319 TIA, age 18–90 years) were included. In 52.6% of all patients, TEE examination revealed relevant findings. Overall, the most common findings in all patients were: patent foramen ovale (21.7%), previously undiagnosed valvular disease (15.8%), aortic plaques, aortic valve sclerosis, atrial septal aneurysms, regional myocardial dyskinesia, dilated left atrium and atrial septal defects. Older patients (greater than 55 years, n = 291) and patients with IS had more relevant echocardiographic findings than younger patients or patients with TIA, respectively (p = 0.002, p = 0.003). The prevalence rates of PFO or ASD were higher in younger patients (PFO: 26.8% vs. 18.0%, p = 0.005, ASD: 9.6% vs. 4.9%, p = 0.014).
All in all, based on these two studies, a third to half of patients with cryptogenic stroke are found to have potential indications for warfarin anticoagulation.
Background: The TOAST classification may be helpful in the determination of cryptogenic stroke.