[Usefulness of coronary angiography in patients undergoing carotid endarterectomy].

We evaluated 37 cases of coronary angiography in patients undergoing carotid endarterectomy (CEA). The severity of coronary stenosis was estimated by Gesini's scoring system. There was no correlation between the severity of carotid stenosis and that of coronary stenosis, but those patients who had a history of coronary artery disease, carotid bruit or intracranial artery stenoses presented significant severe coronary stenosis in most cases. Even in the patients who had no history of coronary artery disease (n = 26), 13 patients (50%) had stenotic lesions shown by coronary angiography. Eight patients required treatment for their coronary stenotic lesions: 5 were treated with percutaneous transluminal coronary angioplasty (PTCA) and 3 with coronary artery bypass grafting. Intraoperative occlusion tests monitored by EEG and SEP showed abnormal findings in 6 CEA operations. One of these patients received PTCA before CEA, and had a good clinical course during and after the CEA procedure. In conclusion, in patients undergoing CEA there is frequently concomitant coronary artery stenosis. We should thus assess the coronary artery lesion more precisely by coronary angiography, and should carry out prophylactic treatment for these lesions.

Catheter ablation therapy in a case with WPW syndrome complicated by multiple tachyarrhythmias.

WPW syndrome is of importance because of the frequent association of tachyarrhythmias. However, its complication by 3 or more different tachyarrhythmias simultaneously is rare. This paper reports a case of WPW syndrome complicated by paroxysmal atrial fibrillation, atrial flutter, and 2 types of atrioventricular reentrant tachycardia. The tachyarrhythmias could be cured by cauterizing the accessory pathway using catheter ablation with radiofrequency electric current. A 30-year-old man visited to a local physician with an episode of tachycardia which failed to resolve, and a diagnosis of WPW syndrome associated with paroxysmal atrial fibrillation was made. The patient was referred to our hospital for further examination and treatment, and electrophysiological study was performed. During the examination, 2 types of atrioventricular reentrant tachycardia with different heart rates were induced, as well as atrial fibrillation and 2:1 atrial flutter. The presence of a left-sided accessory atrioventricular pathway was confirmed by coronary sinus mapping, and the following day catheter ablation was performed and the accessory pathway was cauterized. Subsequently, the delta wave disappeared from the ECG and no additional episodes of tachycardia occurred. Catheter ablation is still undergoing research as a therapeutic modality. However, because the ablation technique entails little invasion or risk, and is economical, it may well become a mainstream treatment for tachycardia in patients with WPW syndrome in the future.

Two sudden death cases of idiopathic ventricular tachycardia.

It is said that the prognosis of idiopathic ventricular tachycardia (IVT) without organic heart disease is good in general. In this paper, two sudden death cases of IVT are reported. The first case was a 44-year-old male, who was referred to our hospital for further examination and treatment of ventricular tachycardia. Echocardiography did not show obvious organic heart disease. After the patient was diagnosed with IVT, he was given drug therapy at the outpatient clinic. However, about six months later, he died suddenly while playing mahjong late at night. The second case was a 17-year-old male. He was also referred to our hospital by another hospital after being diagnosed with ventricular tachycardia. A diagnosis of IVT was made, for which he was given drug therapy at outpatient clinic. However, the patient discontinued receiving the drug therapy. The patient died suddenly about 3 months after discontinuation of the therapy. Some idiopathic ventricular tachycardia cases have poor prognosis like the present ones. It was considered necessary to thoroughly control and guide patients with their daily life and monitor them carefully about the ingestion of anti-arrhythmic agents.

A case of concealed WPW syndrome with three different reciprocal tachycardias due to triple AV nodal pathways.

Triple atrioventricular nodal pathways (TAVNP) occur occasionally, but it is rare for them to produce more than two different tachycardias. Here we report a case of concealed WPW syndrome with three different tachycardias. During electrophysiologic studies, three different reciprocal tachycardias were induced. Tachycardia #1 was characterized by a cycle length of 230 msec and an A'-H interval of 70 msec. For tachycardia #2, these parameters were 300 msec and 140 msec, while they were 370 msec and 200 msec for tachycardia #3. During all three tachycardias, the earliest atrial activity was observed in the left atrium. Ventriculoatrial conduction occurred following ventricular stimulation, and the earliest atrial activity was observed in the left atrium, indicating the existence of left-sided accessory pathway. Persistence of tachycardia for 15-30 min caused marked pulmonary congestion. The heart rate was very high (260 beats/min) during tachycardia #1, and the pulmonary arterial pressure rose to 40/30 mmHg, with the pulmonary arterial diastolic pressure remaining at about 30 mmHg throughout the tachycardia. It seems that the pulmonary venous pressure rises abnormally during paroxysmal supraventricular tachycardia with a very high heart rate and that pulmonary congestion can easily occur during a short period of tachycardia.

Right atrial myxoma with hypervascularity demonstrated by selective coronary angiography.

Cardiac myxoma is the commonest primary cardiac tumor, however, the incidence of right atrial myxoma is very rare. We reported a 71-year-old man with a right atrial myxoma, whose main complaint was fever of unknown origin. Definite diagnosis was confirmed by echocardiography and cineangiocardiography. Venacavogram revealed huge mass which occupied greater part of right atrial cavity. Coronary angiogram revealed the feeding artery arising from left coronary circumflex artery and the sign of hypervascularity. Open heart surgery was performed, and a 4.9 x 4.0 x 3.8 cm tumor was found in the right atrial cavity. Pathological examination showed the findings of myxoma. Postoperative clinical course was uneventful.

The efficacy of isoproterenol on quinidine induced torsade de pointes.

The efficacy of isoproterenol for torsade de pointes (TdP) was evaluated in 60 dogs. TdP was induced in 34 of 60 dogs (56.7%) after the administration of quinidine sulfate (30 mg/kg). The electrophysiologic effect of isoproterenol (0.5 micrograms/min) was studied in 9 dogs with quinidine induced TdP. Isoproterenol significantly shortened basic cycle length, corrected QT interval, effective refractory period (ERP) and dispersion of ERP and increased ERP/QT. Isoproterenol prevented the occurrence of TdP in all dogs. These findings suggest that isoproterenol decreases the dispersion of ventricular refractoriness and may be useful in the treatment of drug induced TdP.