There have been rare reports of H2 blockers causing missed beats and other arrhythmias according to the FDA. http://www.drugs.com/sfx/ranitidine-side-effects.html. However, I have never seen a drug in which this was not the case. I read one report that studied 259 people taking this drug. Of those people, 3 reported missed beats. That would be a normal report from the gen populations. PVC causes can be so individual that maybe it is, but it is not a normal side effect. However, I have spoken with many, many people who get PVC's from acid reflux if that is what you are taking it for.
I am taking the drug to reduce the acid effect to the stomach lining which has been a concern lately.
I am certain that the missing heart beats are caused by the drug but the doctors are reluctant to accept it. I am not sure if I could replace Ranitidine with another drug to do the same job.