薬物性洞機能不全症候群を発症した老年者陳旧性心筋梗塞の1例

Abstract

A case of drug-induced sick sinus syndrome (SSS) in a 60-year-old male with old myocardial infarction is reported. The patient had myocardial infarction in March 1989. He palpitated in August 1998. Paroxysmal supraventricular tachycardia (PSVT) diagnosed by ECG was medicated by disopyramide and procainamide. Then he had syncope attack in October 1998. A sinus arrest for 4.4 seconds was detected on 24- hour Holter ECG. Sinus node recovery time was within normal range after he stopped taking the antiarrhythmic agents. So the patient was diagnosed as having drug-induced SSS. The administration of more than two kinds of antiarrhythmic agents is not certainly safe. Disopyramide and procainamide are reported to have a direct depressant action on normal sinus node cell at the toxic level. In this case the patient had renal dysfunction, so the dose of the antiarrhyttmic agents might be thought to increase to the toxic level.