This was a randomized clinical trial looking at utilizing a modified Valsalva technique to convert supra ventricular tachycardia (SVT) to sinus rhythm. The results of applying the modified Valsalva technique demonstrated a 43% conversion rate versus a 17% conversion rate with standard Valsalva technique.
 
The best way to describe this modified technique is for you to watch this short (2 minutes) You tube video presented by one of the investigators of the REVERT study. This is a great technique that all emergency personnel should be thinking about implementing next time faced with a patient in SVT.
Modified Valsalva – REVERT Study - https://www.youtube.com/watch?v=8DIRiOA_OsA