Forced expiratory effort against a closed GLOTTIS.
http://www.cochrane.org/fr/CD009502/efficacite-de-la-manoeuvre-de-valsalva-pour-supprimer-un-rythme-cardiaque-anormal 2015 false United Kingdom France French meta-analysis french abstract tachycardia, supraventricular treatment outcome valsalva maneuver