TCD is Superior to TEE for Detection of PFO (Patent Foramen Ovale)
AHAScience News-International Stroke Conference 2014-San Diego
In this video Ralph Sacco, MD, FAHA, past-president of the American Heart Association, interviews David Spence, MD, primary investigator of the trial, “Transcranial Doppler Is Superior to Transesophageal Echocardiography in Detection of Patent Foramen Ovale,” which he presented at ISC 2014 in San Diego.
TCD and PFO Study Summary:
The researchers conducted a study to compare the performance of transcranial Doppler (TCD) with transesophageal echocardiography (TEE), the standard method for diagnosing a right-left shunt such as PFO. They hypothesized that transcranial Doppler saline studies would be more sensitive, in part because sedation for TEE could prevent an adequate Valsalva maneuver.
The study included 340 patients (mean age, 53 years, 61.5% women) with cryptogenic stroke and suspected paradoxical embolism who were referred to an urgent transient ischemic attack clinic from 2000 to 2013.
Right-left shunt was detected in all 340 patients by transcranial Doppler, but TEE failed to show right-left shunt in 15.4% of patients, according to Spence. “In some cases, it missed quite big shunts,” he said. Of the missed shunts, a quarter were grade 3 or higher.
During median follow-up of 420 days, 85 patients had a recurrent ischemic stroke or TIA. Survival free of stroke was predicted by transcranial Doppler shunt of grade 3 or more (P=.008), but not by TEE (P=.6) as reported by Spence.
According to Spence the study revealed that transcranial Doppler is better for both diagnosing (because it is more sensitive), and risk stratifying,” he said, noting that the technologies are complementary because “you need [TEE] to find other causes of stroke from the heart.”