Key result
The modified Valsalva maneuver significantly increased the positive detection rate of right-to-left shunt compared to the simple cough maneuver (89.5% vs. 82.1%, p=0.017) during contrast-enhanced transcranial Doppler.
Why the study?
Does the modified Valsalva maneuver improve the detection rate of right-to-left shunts compared to coughing during contrast-enhanced transcranial Doppler in patients suspected of having a shunt?
Cross-Sectional (n=162)
Blinded assessors
Randomized test order
No
Does the modified Valsalva maneuver improve the detection rate of right-to-left shunts compared to coughing during contrast-enhanced transcranial Doppler in patients suspected of having a shunt?
Absolute Event Rate: 89.5% vs 82.1%
p-value: p=0.017
The modified Valsalva maneuver is significantly more effective than the simple cough maneuver for detecting and grading the severity of right-to-left shunts during contrast-enhanced transcranial Doppler.
Modified VM detects more RLS than coughing by c-TCD; supports standardized preference but leaves optimal protocols open for validation.
Contrast-enhanced transcranial Doppler (c-TCD) has been used to detect right-to-left shunts (RLS) because it is highly sensitive and cost-effective. The use of provocation maneuvers, such as physiologic maneuvers (e.g., coughing) and the Valsalva maneuver (VM) to transiently increase right atrial pressure and induce RLS increases the sensitivity of RLS detection. In this study, we sought to determine whether coughing is as effective as the VM in aiding the detection of RLS. We evaluated 162 subjects for RLS, using c-TCD under three different conditions: (i) resting state, (ii) coughing, and (iii) modified VM (m-VM), which involved blowing into a tube connected to a sphygmomanometer at 40 mmHg for 10 s. The positive rate of RLS detection with the m-VM was significantly higher than that with coughing. In addition, a difference between the two maneuvers was observed in terms of the degree of RLS seen. The m-VM should be widely used to detect RLS, because it is reliable, standardized, and cost-effective.
No takes yet. Share an insight, caveat, or question.
Wang et al. (2017) conducted a cross-sectional in Right-to-left shunt (RLS) (n=162). Modified Valsalva maneuver (m-VM) vs. Simple cough maneuver was evaluated on Positive rate of RLS detection (p=0.017). The modified Valsalva maneuver significantly increased the positive detection rate of right-to-left shunt compared to the simple cough maneuver (89.5% vs. 82.1%, p=0.017) during contrast-enhanced transcranial Doppler.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: