Shortening of R-PP interval by verapamil in reciprocating tachycardia.
D004562:Electrocardiography; D005260:Female; D006801:Humans; D008875:Middle Aged; D013610:Tachycardia / Q000188:drug therapy*; D014700:Verapamil / Q000627:therapeutic use*
D014700:Verapamil