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Patients with LQTS (long QT syndrome) with a mutation in a cardiac ion channel gene, leading to mild-to-moderate channel dysfunction, may manifest marked QT prolongation or torsade de pointes only upon an additional stressor. A 59-year-old woman had marked QT prolongation and repeated torsade de pointes 3 months after initiation of probucol, a cholesterol-lowering drug. We identified a single base substitution in the HERG gene by genetic analysis. This novel missense mutation is predicted to cause an amino acid substitution of Met(124)-->Thr (M124T) in the N-terminus. Three other relatives with this mutation also had QT prolongation and one of them had a prolonged QT interval and torsade de pointes accompanied by syncope after taking probucol. We expressed wild-type HERG and HERG with M124T in Xenopus oocytes and characterized the electrophysiological properties of these HERG channels and the action of probucol on the channels. Injection of the M124T mutant cRNA into Xenopus oocytes resulted in expression of functional channels with markedly smaller amplitude. In both HERG channels, probucol decreased the amplitude of the HERG tail current, decelerated the rate of channel activation, accelerated the rate of channel deactivation and shifted the reversal potential to a more positive value. The electrophysiological study indicated that QT lengthening and cardiac arrhythmia in the two present patients were due to inhibition of I(Kr) (rapidly activating delayed rectifier K(+) current) by probucol, in addition to the significant suppression of HERG current in HERG channels with the M124T mutation.

We herein report the case of a 65-year-old man with pericardial involvement associated with autoimmune pancreatitis. Chest CT imaging showed pericardial thickening. The patient responded to corticosteroid therapy, and the pericardial thickening resolved. Multiple organs are involved in immunoglobulin G4 (IgG4)-related disease (IgG4-RD); however, only a few cases of IgG4-related chronic constrictive pericarditis have been reported. To our knowledge, this is the first reported case of IgG4-RD with pericardial involvement at an early stage. This case indicates that recognizing pericardial complications in autoimmune pancreatitis is important and that CT imaging may be useful for obtaining the diagnosis and providing follow-up of pericardial lesions in cases of IgG4-RD.

Circ J 2009; 73: 589 -592 ransient left ventricular dysfunction with chest symptoms and electrocardiographic (ECG) changes mimicking those of acute myocardial infarction are known as takotsubo cardiomyopathy. [1][2][3] Although the pathogenesis of takotsubo cardiomyopathy remains unclear, physical or emotional stress is common and elevation of plasma catecholamines suggests that sympathetic stimulation plays a central role. When medical support is provided promptly, the long-term prognosis of takotsubo cardiomyopathy is generally good with full recovery of left ventricular contraction. Patients with takotsubo cardiomyopathy generally show T-wave inversion and QT-prolongation during the early phase, and these ECG changes typically normalize within several weeks with improvement of left ventricular wall motion. [1][2][3] The arrhythmias associated with takotusbo cardiomyopathy include atrioventricular (AV) block, sinus bradycardia, paroxysmal atrial fibrillation, ventricular tachycardia and ventricular fibrillation. [2][3][4][5][6][7][8][9] Here, we describe a case of takotsubo cardiomyopathy demonstrating persistent complete AV block after improvement of left ventricular wall motion that needed the implantation of a pacemaker. Case ReportAn 82-year-old woman with no history of cardiac disease or hypertension presented to the emergency department due to repeated episodes of syncope with incontinence. She had been stressed for about 2 weeks and could not sleep well because she was caring for her grandchildren who had been injured in a traffic accident. The patient had taken care of her grandchildren over the night before admission and complained of fatigue but denied chest pain. There was no family history of heart disease or sudden death. She had no history of arrhythmia or prior syncope. On admission her blood pressure was 110/72 mmHg, the pulse was 38 beats/min and body temperature was 35.6ºC. Her consciousness was clear, and a neurological examination revealed no neurological deficits. She had a repeated syncope lasting for about 10 s presenting torsades de pointes on monitoring ECG in the emergency department. The 12 leads ECG on admission showed complete AV block, diffuse T-wave inversions in leads I, aVL, V2-6 and prolonged QTc interval of 630 ms (Figure 1). Chest X-ray showed mild cardiomegaly and no pulmonary congestion. The laboratory data on admission are shown in Table 1. The serum level of creatine kinase was normal, but the rapid cardiac Troponin T assay was positive. Serum electrolytes, plasma norepinephrine and adrenaline levels were within the normal range. An elevated plasma level of brain natriuretic peptide suggested cardiac dysfunction. Echocardiography revealed akinesis in the left ventricular apical wall and no pericardial effusion. A temporary transvenous pacemaker was inserted due to complete AV block and to prevent the recurrence of torsade de pointes. Urgent coronary angiography was carried out and showed no significant coronary stenosis or vascular obstruction. Left ventriculography ...

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