Transcranial Doppler ultrasound identifies patients with right‐to‐left cardiac or pulmonary shunts

Background and Purpose-Patent foramen ovale (PFO) is a risk factor for paradoxical embolism, and severe shunting and wide opening of PFO are risk factors for severe and recurrent cerebrovascular events. Neither contrast echocardiography nor 2-dimensional (2D) measurement of PFO size have been validated or compared with invasive balloon sizing. Methods-We performed transesophageal echocardiography (TEE) in 100 patients with cryptogenic stroke and catheter closure of PFO. The amount of contrast shunting through the PFO during cubital and femoral contrast delivery and the PFO size measured by 2D TEE were compared with balloon sizing. Results-There was a significant correlation (r 2 ϭ0.8; PϽ0.0001) between 2D TEE measurement and invasive balloon sizing. Mean balloon-sized PFO diameter was significantly larger than mean PFO diameter measured by 2D TEE (8.3Ϯ2.6 versus 5.2Ϯ1.7 mm). Semiquantitative contrast TEE correlated with PFO size (r 2 ϭ0.7; PϽ0.0001) only if the contrast agent was administered through a femoral vein. Correlation was poor when the contrast agent was administered via a cubital vein. Conclusions-We conclude that 2D TEE measurement of a PFO size is more accurate than the traditionally used contrast technique. (Stroke. 2002;33:293-296.)

Section: Discussionmentioning

confidence: 99%

Transesophageal Echocardiography for Quantifying Size of Patent Foramen Ovale in Patients With Cryptogenic Cerebrovascular Events

Schuchlenz¹,

Weihs²,

Beitzke³

et al. 2002

“…14 Therefore, performance of the VM before injection does not make sense. 20,25 In most studies, VM was performed after injection. Zanette et al 15 were the first to systematically investigate the most appropriate timing for the performance of the VM.…”

Section: Discussionmentioning

confidence: 99%

Contrast Transcranial Doppler Ultrasound in the Detection of Right-to-Left Shunts

Droste

Silling

Stypmann

et al. 2000

107

Background and Purpose-Cardiac right-to-left shunts can be identified by transesophageal echocardiography (TEE) and by transcranial Doppler ultrasound (TCD) with the use of contrast agents and a Valsalva maneuver (VM) as provocation procedure. Currently, data on the appropriate timing of the VM, the use of a diagnostic time window, and a threshold in contrast agent microbubbles detected are insufficient. Methods-Fifty-eight patients were investigated by both TEE and bilateral TCD of the middle cerebral artery. The following protocol with injections of 10 mL of the commercial galactose-based contrast agent Echovist was applied in a randomized way: (1) no VM, (2) VM for 5 seconds starting 2 seconds after the beginning of contrast injection, (3) VM for 5 seconds starting 5 seconds after the beginning of contrast injection, (4) VM for 5 seconds starting 8 seconds after the beginning of contrast injection, and (5) repetitive short VMs in between 2 and 13 seconds after the beginning of contrast injection. In addition to the single tests, we also tested the sensitivity and specificity of combined results of the tests with VM. Results-In 21 patients, a right-to-left shunt was demonstrated by TEE and contrast TCD (shunt positive). Twenty-one patients were negative in both investigations, no patient was positive on TEE and negative on TCD, and 16 patients were only positive on at least 1 TCD investigation but negative during TEE. Test 3 was the most appropriate test when combined with the results of 1 of the other tests with VM. The highest sensitivities were achieved with a diagnostic time window of 40 seconds and when the presence of a single microbubble was sufficient for the diagnosis of a shunt. Conclusions-TCD performed twice with 2 provocation maneuvers with Echovist is a sensitive method to identify TEE-proven cardiac right-to-left shunts. The VM should be performed for 5 seconds starting at 5 seconds after the beginning of contrast injection.

“…The bubble artifact was usually accompanied by a chirp that indicated a power amplitude of short duration in a high-frequency spectrum. 7 When at least one spike appeared less than 25 seconds after injection, we considered TCD positive and assumed direct passage through the PFO. When the onset of bubble shower was later than 25 seconds, pulmonary passage was assumed.…”

Section: Stroke Vol 25 No 6 June 1994mentioning

confidence: 99%

A comparison of transesophageal echocardiography and transcranial Doppler sonography with contrast medium for detection of patent foramen ovale.

Jauß

Kaps

Keberle

et al. 1994

139

102

Background Patent foramen ovale as a possible stroke risk factor can be diagnosed with transcranial Doppler sonography (TCD) by detecting intravenous contrast medium crossing from the right to the left atrium. The present study evaluates the reliability of this method.Summary of Report We performed TCD and transesophageal echocardiography simultaneously in 50 patients using galactose microbubbles. We observed bubble signals passing the middle cerebral artery in 7 patients less than 20 seconds after injection; we found positive TCD tests in 14 patients