Sinus node dysfunction concomitant with Brugada syndrome.

BACKGROUND: A genetic correlation between Brugada syndrome (BS) and sinus node dysfunction (SND) has been proposed, although the clinical and electrophysiologic characteristics of this concomitant condition are unknown. METHODS AND RESULTS: The study comprised 5 patients with symptomatic BS (4 with spontaneous episodes of ventricular fibrillation (VF) and 1 with syncope) of whom 3 had a documented sinus pause > 3 s (a 42- and 62-year-old man, and a 49-year-old woman). Only 1 of them had a family history of sudden death; 2 of them had also had an episode of atrial fibrillation or flutter. Electrophysiologic study demonstrated prolonged sinus node recovery time in 2 patients (2.6 s and > 5 s), in whom a cardiac pacemaker had been implanted before the diagnosis of BS was made after episodes of VF. Finally, all 3 patients received an implantable cardioverter defibrillator, including 2 upgrades from pacemaker. CONCLUSIONS: SND is not a rare concomitant disorder in BS and there is a possible genetic connection.

Localized dissection of the sinus of valsalva without coronary artery involvement during percutaneous coronary intervention.

Dissection of the sinus of Valsalva is an extremely rare accident during percutaneous coronary intervention (PCI), but it can lead to serious complications such as dissection of the ascending aorta. We experienced a localized dissection of the right coronary cusp without coronary artery involvement that was induced by a guiding catheter during PCI in a patient with acute myocardial infarction. The localized dissection showed pooling of the contrast medium in the acute phase, but it subsided spontaneously after 12 days without any sequelae. Manipulation of the guiding catheter should be performed with great caution not only in the coronary artery but also in the sinus of Valsalva.

Conversion and maintenance of sinus rhythm by bepridil in patients with persistent atrial fibrillation.

BACKGROUND: Bepridil has multiple ion-channel blocking effects similar to amiodarone and is expected to have anti-arrhythmic effects that are useful for the management of atrial fibrillation (AF). The aim of this study was to clarify the conversion of persistent AF and maintenance of sinus rhythm (SR) by oral bepridil. METHODS AND RESULTS: Oral bepridil was administered to 112 patients (83 males, 29 females; age: 59.0+/-10.8 years) with persistent AF lasting an average of 5 months. The conversion effects and maintenance of SR after pharmacological or direct current (DC) cardioversion, as well as the incidence of adverse complications, were evaluated. In 65 of 112 (58%) patients, SR was restored within 6 months (average: 2.1 months) following bepridil administration. DC cardioversion was carried out for 21 of the remaining 47 patients with unsuccessful pharmacological conversion, and all had restoration of SR. Eventually, of the 86 patients in total who were restored to SR by either bepridil or DC cardioversion, 70 (81%) patients maintained SR after a mean follow-up of 18 months. No serious adverse complications were observed, except for marked QT prolongation in 2 cases. CONCLUSION: Bepridil showed favorable conversion effects in patients with persistent AF and was highly effective for maintaining SR after pharmacological or electrical cardioversion. However, careful follow-up is necessary for the prevention of torsade de pointes caused by QT prolongation.

Vasovagal response induced by a low dose of isoproterenol infusion before tilting-up.

A 56 year-old man was referred to hospital for evaluation of syncopal episodes. During head-up tilt testing, his symptom was reproduced, associated with bradycardia and hypotension, by a low dose of isoproterenol (0.02 microg. kg (-1). min(-1)) infusion in the supine position before tilting-up. Isoproterenol infusion can provoke a vasovagal response without tilting. Careful observation of the patient's hemodynamics is mandatory not only during tilting, but also in the supine position before tilting-up.

Dislodgment of an atrial screw-in pacing lead 10 years after implantation.

Dislodgment of an atrial screw-in pacing lead is quite rare. This report describes a rare case of an atrial screw-in lead dislodgment 10 years after implantation. Although it is an uncommon complication, very late dislodgment can occur postoperatively, and careful follow-up is necessary.

Primary coronary angioplasty with stenting for acute coronary syndrome in patients with isolated single coronary artery: a report of 2 cases.

We report 2 cases with an isolated single coronary artery who underwent successful primary coronary intervention for acute coronary syndrome. Although coronary angioplasty with stenting may be a feasible therapeutic option for atherosclerotic stenosis in a single coronary artery, the operator should be aware of the potential risk of complications.

Atrioventricular block during atrioventricular nodal reentrant tachycardia is not always benign.

A 70-year-old Japanese woman was admitted to our hospital because of transient second degree atrioventricular (AV) block. An electrophysiologic study (EPS) was performed, and Mobitz type II infra-Hisian block during atrial pacing at a rate of 130/min was noted. An AV nodal reentrant tachycardia (AVNRT) was induced by ventricular pacing at a rate of 180/min, and 2:1-3:1 infra-Hisian block during AVNRT was observed. The AV block and AVNRT rarely occurred in the clinical setting, and the patient did not complain of any symptoms related to these arrhythmias. Therefore, the patient refused permanent pacemaker implantation, although she continued to be followed in our outpatient clinic. However, the patient was re-admitted one year later because of palpitations and dyspnea upon exertion related to the AV block. The 12-lead ECG showed high degree AV block with narrow QRS complexes. The patient underwent pacemaker implantation during the subsequent hospitalization, and her symptoms improved postoperation. AV block during AVNRT is sometimes observed, and it has been considered as a functional AV block. In the present case, a pathologic conduction disturbance in the His-Purkinje system caused the high degree AV block during AVNRT. The high degree AV block during AVNRT may indicate the existence of a conduction disturbance in the His-Purkinje system in some of these types of cases.

Cardiac hemangioma: a report of two cases and review of the literature.

Cardiac hemangioma is extremely rare. We encountered two patients with cardiac hemangioma detected by thoracic echocardiography during a medical checkup. In the first case, transthoracic echocardiography revealed a pedunculated tumor in the left ventricle. Selective left coronary angiography demonstrated that the main feeding artery of the tumor arose from the third diagonal branch of the left anterior descending coronary artery. In the second case, thoracic and transesophageal echocardiography showed an oval tumor arising from the right atrium. Both tumors were successfully resected. Histopathological examination revealed that one of the tumors was a capillary hemangioma and the other was a mixed capillary and cavernous hemangioma. After operation, both patients had an uneventful recovery without any complications.

Superior vena cava syndrome due to fibrosing mediastinitis histologically identical to xanthogranulomatous pyelonephritis.

We present herein a case of superior vena cava (SVC) syndrome caused by localized fibrosing mediastinitis (FM), which had histological features similar to xanthogranulomatous pyelonephritis (XGP). A 63-year-old woman presented with facial swelling 5 months after undergoing right nephrectomy for XGP. Radiologic investigations of the chest confirmed the presence of SVC obstruction due to an intraluminal tumor. The histological features of the tumor were consistent with those of FM and were very similar to those of XGP. Although the pathogenesis of neither FM nor XGP is known, some pathogenic process of FM and XGP may be the same.

What is the optimal increase in resting heart rate with low dose isoproterenol infusion for tilt-induced vasovagal response?

Isoproterenol is widely used as a provocative medium for vasovagal responses during tilt testing. Dose of isoproterenol infusion is generally titrated empirically by increase in resting heart rate before tilt up. To determine the optimal increase in resting heart rate with isoproterenol for tilt-induced vasovagal responses, we studied 97 consecutive patients with unexplained syncope. After the end of a negative baseline tilt (80 degrees for 30 min), the isoproterenol tilt was performed using one of two protocols: two-stage isoproterenol-tilt protocol, with doses of 0.01 and 0.02 microg/kg per min for 10 min each, or one-stage isoproterenol-tilt protocol, with a dose of 1 or 2 microg/min for 10 min. The resting heart rate increase was defined as a percentage increase in the resting heart rate after isoproterenol infusion, compared to the baseline heart rate before the tilt test. In 117 tilt procedures, 28 (93%) of the 30 positive responses occurred with a resting heart rate increase of > or = 21%. With the resting heart rate increase of 60 and 100%, 18 (60%) and 27 (90%) positive responses were observed, respectively. In conclusion, the minimum resting heart rate increase of > or = 21% was required to provoke a vasovagal response during subsequent isoproterenol-tilt (80 degrees for 10 min). Preferably, heart rate should be increased to 60-100% by isoproterenol titration before tilting.