[A case report of two mitral valve aneurysms with one perforation after two attacks of infective endocarditis].

Aneurysms of the mitral valve complicating infective endocarditis (IE) are uncommon. The patient was a 57-year-old man who was admitted to our hospital for a precise examination of heart failure. One year before, the first two-dimensional echocardiography showed an aneurysm of the anterior mitral leaflet possibly due to a previous attack of IE. Doppler color flow mapping detected a regurgitant jet from the mitral valve aneurysm into the left atrium during systole, which suggested perforation of the aneurysm, and an aortic regurgitant jet flowing against the anterior mitral leaflet. Because the patient's family refused cardiac catheter examination and surgery, we treated him in the out-patient clinic. A few weeks before his admission, he had discontinued taking diuretics because of uncomfortable urinary frequency. He gradually developed the symptoms of heart failure and entered our hospital. IE was suspected because of leucocytosis and slight fever. Two-dimensional echocardiography revealed a new aneurysm of the anterior mitral leaflet without perforation, located in the distal part of the old aneurysm. This time, his family consented to the surgical treatment. Aortic and mitral valve replacement was successfully performed. It was pathologically confirmed that the two mitral aneurysms had been caused by IE.

Electrophysiological effects of disopyramide phosphate in patients with sinus node dysfunction.

The electrophysiological effects of intravenous administration of disopyramide (1.5 mg/kg) were studied in 26 patients with sinus node dysfunction (SND). Disopyramide shortened spontaneous cycle length (SCL) in 12 patients and lengthened it in 4. Maximum sinus node recovery time (max SRT) was prolonged in 9 patients and shortened in 6. Estimated sinoatrial conduction time (SACT) was prolonged in 4 and shortened in 4 out of 10 patients in whom this measurement was possible. However, these changes were not statistically significant. Neither were there any significant changes in PA and AH intervals nor refractory periods of the AV node. HV intervals and refractory periods of the atrium at matched cycle length were significantly lengthened. Atrial echo beats and atrial premature beats disappeared in 7 of 12 patients treated with disopyramide. In all of these 7 patients atrial refractory period were increased. Thus, the disappearance of atrial echo beats and atrial premature beats was thought to be due to a prolonged atrial refractoriness. In 4 patients who had supraventricular arrhythmias without having either marked prolongation of max SRT or episodes of syncope, disopyramide was administered orally for a long term, during which these arrhythmias and symptoms disappeared and sinus rate increased. These results suggest that disopyramide is useful in patients with SND and supraventricular arrhythmias.

Electrophysiological effects of lidocaine in sick sinus syndrome.

Electrophysiological studies were performed to see the effects of lidocaine on the conduction system, particularly sinus node and atrium in 40 patients of SSS, using HBE recordings, rapid atrial pacing and atrial extrastimulus technique. Sinus cycle length, PA (P'A), AH, HV intervals, calculated SACT, and refractory periods of atrium, AV node and His-Purkinje system did not change after lidocaine. Only maximum CSRT was significantly increased with lidocaine. These results were not affected by pretreatment of atropine. In conclusion, the combining rapid atrial pacing with lidocaine may be useful to manifest the masked sinus node abnormalities. It was suggested that lidocaine directly depressed sinus node automaticity in SSS patients, without affecting perinodal tissue. Therefore, lidocaine should be used with caution in patients with known or suspected SSS.