I was interested to see this post bumped back up as it was just what I came on to look for. I have WPW, usually marked by tachycardia, but over the last few weeks I have been having multiple spells a day of palpitations during which my heart rate is falling into the 40s (and I've seen it go as low as the high 30s). I've had episodes of bradycardia in the past, but never so frequent or with such symptoms. It is accompanied by a dry cough, which I have read can be a natural response of the body to reset the rate. I've been on Cosentyx since early March, but this didn't start until late April. Thankfully, I have may annual cardiology check-up next week. It is really freaking me out.