A new Valsalva blowing device in the diagnosis of right-to-left shunt using contrast-enhanced transcranial Doppler ultrasound.
Patent foramen ovale (PFO) is a remnant of normal fetal anatomy and is present in approximately 25% of adults. PFO mainly causes right-to-left shunt (RLS). Clinical identification of RLS is crucial for certain patients, particularly those with a history of cryptogenic stroke or other embolic events. Contrast-enhanced transcranial Doppler ultrasound (c-TCD) is a commonly used, noninvasive method for the detection of RLS. In this study, we explored the application of a modified Valsalva blowing device for the diagnosis of RLS using c-TCD.
The data of 805 patients with high clinical suspicion of PFO, who underwent c-TCD at Shaanxi Provincial People's Hospital between January and October 2024, were collected and analyzed. All 805 patients first completed resting-state c-TCD, followed by c-TCD using the traditional Valsalva maneuver and the modified Valsalva blowing device in random order. The RLS detection rate and shunting extent of the two methods were compared.
The detection rate using the traditional Valsalva maneuver was 395 RLS-positive patients (49.1%), but it increased significantly when using the modified Valsalva blowing device (475 positive patients, 59%, P < 0.01). In addition, the diagnosis of the shunting extent differed significantly between the traditional Valsalva maneuver and the modified Valsalva blowing device (P < 0.01).
The modified Valsalva device has higher sensitivity in the diagnosis of RLS than the traditional Valsalva maneuver, especially for higher grade shunting severity. It can be used as an alternative to the traditional Valsalva maneuver in c-TCD screening, particularly in patients who have difficulty performing the traditional Valsalva maneuver.
The data of 805 patients with high clinical suspicion of PFO, who underwent c-TCD at Shaanxi Provincial People's Hospital between January and October 2024, were collected and analyzed. All 805 patients first completed resting-state c-TCD, followed by c-TCD using the traditional Valsalva maneuver and the modified Valsalva blowing device in random order. The RLS detection rate and shunting extent of the two methods were compared.
The detection rate using the traditional Valsalva maneuver was 395 RLS-positive patients (49.1%), but it increased significantly when using the modified Valsalva blowing device (475 positive patients, 59%, P < 0.01). In addition, the diagnosis of the shunting extent differed significantly between the traditional Valsalva maneuver and the modified Valsalva blowing device (P < 0.01).
The modified Valsalva device has higher sensitivity in the diagnosis of RLS than the traditional Valsalva maneuver, especially for higher grade shunting severity. It can be used as an alternative to the traditional Valsalva maneuver in c-TCD screening, particularly in patients who have difficulty performing the traditional Valsalva maneuver.