^ That's what my SVT felt like, like I wasn't getting enough blood to my brain because my heart was beating too fast. The episodes would often strike when I was biking or in the gym. For some reason, if I was doing a cardio-type exercise, I'd just feel tired and heavy. I'd usually tough it out knowing that my heart would snap back to a normal rhythm within 30-40 seconds. But if an episode hit after a set while weight training or at some other time, I'd often start feeling faint and sometimes out of breath. These episodes seemed to last longer. Sometimes the valsalva maneuver helped. Since having my SVT treated, I've heard about a modified maneuver that may be more effective:
The REVERT Trial: A Modified Valsalva Maneuver to Convert SVT - R.E.B.E.L. EM - Emergency Medicine Blog
"In patients with cardiovascularly stable supraventricular tachycardia (SVT), the valsalva maneuver is recommended as an initial maneuver to help with cardioversion. The success rate of the valsalva maneuver alone is documented at 5 – 20%. The next option for patients who still remain in SVT is intravenous adenosine. Adenosine briefly stops all conduction through the AV node, which causes patients to feel a sense of doom or like they are about to die. Increasing venous return and vagal stimulation by laying patients supine and elevating their legs may increase the rate of conversion and is simple, safe, and cost effective."
The REVERT Trial: A Modified Valsalva Maneuver to Convert SVT - R.E.B.E.L. EM - Emergency Medicine Blog
"In patients with cardiovascularly stable supraventricular tachycardia (SVT), the valsalva maneuver is recommended as an initial maneuver to help with cardioversion. The success rate of the valsalva maneuver alone is documented at 5 – 20%. The next option for patients who still remain in SVT is intravenous adenosine. Adenosine briefly stops all conduction through the AV node, which causes patients to feel a sense of doom or like they are about to die. Increasing venous return and vagal stimulation by laying patients supine and elevating their legs may increase the rate of conversion and is simple, safe, and cost effective."