In patients with supraventricular tachycardia, does a modified Valsalva maneuver improve the rate of conversion to sinus rhythm compared to the standard Valsalva?
A modified Valsalva maneuver converted a significantly higher proportion of patients with supraventricular tachycardia into normal sinus rhythm.
Though vagal maneuvers are consistently recommended as first-line treatment for supraventricular tachycardia due to having a low risk for adverse events, they also have historically low rates of efficacy (5-20%) at conversion to sinus rhythm.
In the REVERT trial (2015), investigators examined a modified Valsalva in a randomized controlled trial which demonstrated superior efficacy to traditional vagal maneuvers, featuring a 43% rate of conversion of SVT to sinus rhythm. To perform this modified maneuver, Valsalva was performed for 60 seconds in a 45° position followed immediately by a switch to being laid flat with legs raised by a member of staff to 45° for 15 seconds. In each position, the 45 degree angle allows for optimization of change in blood flow.
Given the low risk and superior efficacy of this modified maneuver, it is likely to become the new standard of care for SVT abatement and can potentially be taught to patients at risk for recurrent SVT.
No guidelines currently reflect the modified Valsalva maneuver at this time.
- Multicenter randomized, controlled trial
- Standard Valsalva (n=216)
- Modified Valsalva (n=217)
- Setting: 10 centers in the UK
- Enrollment: January 2013 - December 2014
- Analysis: Intention-to-treat
- Primary outcome: Sinus rhythm at 1 minute after Valsalva by EKG
- Age ≥18 years
- Supraventricular tachycardia
- Unstable patients, with SBP<90 or indication for immediate cardioversion
- Atrial fibrillation, atrial flutter, or sinus tachycardia
- Contraindication to Valsalva (Aortic stenosis, recent MI, glaucoma, retinopathy)
- Inability to perform Valsalva, lie flat, or have legs lifted
- No significant differences between groups.
- Demographics: Age 55 years, 60% female, 4% ischemic heart disease
- Similar comorbidities (DM2, HTN, Pneumonia, COPD, valvular disease)
- Similar vitals (SBP, DBP, HR, O2 sat)
Patients were randomized to:
- Standard Valsalva (n=216), renamed "Stay sitting Valsalva" to reduce bias.
- Description: 60 second strain positioned semi-recumbent (at 45°)
- Modified Valsalva (n=217), renamed "Lying down with leg lift Valsalva" to reduce bias.
- Description: 60 second strain in a 45° position followed immediately by a switch to being laid flat with legs raised by a member of staff to 45° for 15 seconds
- A 3-lead ECG was used 1 minute after initial Valsalva to reassess cardiac rhythm. If still not in sinus, participants were invited one further attempt at the allocated Valsalva maneuver.
- A 12-lead ECG was used 1 minute after initial or second Valsalva attempt to determine final cardiac rhythm, even if unsuccessful.
Comparisons are standard vs. modified.
- Conversion to sinus rhythm
- 17% vs 43% (OR 3.7; 95% CI 2.3-5.8; P<0.0001)
- Adenosine given
- 69% vs. 50% (OR 0.45; 95% CI 0.30-0.68; P<0.0002
- Emergency anti-arrhythmic treatment
- 80% vs. 57% (OR 0.33; 95% CI 0.21-0.51; p<0.0001)
- No significant differences in discharge from ED or time spent in ED
No significant differences in adverse events
- Though the Modified Vagal maneuver appears to be safe and effective, it does not appear to confer any advantages to adenosine in terms of safety, tolerability, efficacy, or hospital resources
- Clinicians were not masked to treatment allocation, although this is unlikely to have skewed results given the objective and algorithmic treatment pathway for SVT
Funded by National Institute for Health Research. No conflicts of interest declared or identified.