Lidoflazine as an Antiarrhythmic Drug

Mitsuo Miyahara, Osamu Iimura, Minoru Yokoyama, Koki Hoshikawa
1969 Tohoku journal of experimental medicine  
Since Schaper and his coworkers1-3 reported an excellent coronary vasodilating action of lidofiazine, a drug originally prepared in Janssen Pharmaceutica Institute, on conscious dogs with a previously implanted electromagnetic flow meter, the antianginal effect of the drug has been clinically investigated in our own and other laboratories. Its usual dose is 90 or 120mg per day. Recently, we administered a large dose of lidoflazine (90mg three times a day) to a patient with atrial fibrillation
more » ... rial fibrillation due to coronary heart disease, and a reversion to sinus rhythm was unexpectedly recognized. Since there has been no report on such a defibrillating effect of this drug, and since a chemical structure of lidofiazine is similar to that of lidocain which has been recommended for clinical use as an effective antiarrhythmic drug,4-7 we think it adequate to evaluate the effect of lidofiazine in the treatment of atrial fibrillation and of other arrhythmias. The present paper is a preliminary report of the results obtained up to the present. Patients with established atrial fibrillation were divided into two groups according to the procedure of medication. The first group consisted of seven patients who were given a large dose of lidofiazine (270 or 180mg per day). The second group consisted of five patients who received an initial dose of 60mg per day, and then the dose was gradually increased by 30 or 60mg up to 270mg as the maximum dose. In addition, the drug was given to three other patients with paroxysmal atrial fibrillation and to another with paroxysmal tachycardia. In all seven cases of the first group, established atrial fibrillation was con verted to sinus rhythm. A reversion occurred within one to two days in 5 out of 7 patients, and within 4 to six days in the other two. Fibrillation did not re appear despite immediate discontinuation of the drug in all except two cases. In two cases of patients with mitral valvular disease in a state of congestive heart failure who were given a maintenance dose of digitoxin, several arrhythmias such as atrioventricular block, ventricular premature beat, ventricular tachycardia or ventricular fibrillation (in one case) occurred with only transient reversion to sinus rhythm. These arrhythmias occurred after one day (total 270mg) in one case and after only 120mg (60mg, two times) in the other.
doi:10.1620/tjem.97.95 fatcat:xdxd7njvrnhqfmrmi72s2orb4m