quinidine increased effective refractory period ( +40 % ; p less than .01 ) , functional refractory period ( +27 % ; p less than .01 ) , conduction time at sinus cycle length ( +13 % ; p less than .01 ) , conduction time at an atrial paced cycle length of 150 msec ( +18 % ; p less than .01 ) , and atrial flutter cycle length ( +31 % ; p less than .01 ) .
C0034414
quinidine
C0004239
atrial flutter