Objective : QT interval prolongation and torsade de pointes (TdP) are associated with congenital long QT syndrome. It is known that automated analysis and the tangent method produce different QT interval results, but the degree of difference is not well known. We investigated the difference between automatic measurement and the tangent method. Method : We compared the results of QT interval measurement by automatic measurement with an electrocardiograph (ECG-1450, Nihon Kohden) and the tangent method by cardiologists on leads II and V₅. The number of cases was 200 males and females of ages 7, 13 and 16 years old.
Results : The difference between automatic measurement and tangent method was 25.4 msec ±19.7 msec in II and 31.9 msec ±18.0 msec in V₅ (mean ± standard deviation). Automatic measurement gave a longer QT interval in each lead. Discussion : There is a difference between the tangent measurement method and automatic measurement method when screening QT interval.

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Background : Pulmonary vein isolation (PVI) is the established therapeutic approach for paroxysmal atrial fibrillation (PAF). Multiple procedures are still required in 20 to 30% of patients for the recurrence of AF/AT. Method and Result : Sixty-one Consecutive patients (42 males and 61±13 yrs. old) who underwent the 2nd procedure for recurrent AF/AT were enrolled among 300 patients with PVI for PAF in our center. AF/AT recurrence was observed in 21 of the 61 patients after the 2nd procedure, including 12 PAF and 9 AT. Between the recurrence group (R-group, n=21) and the non-recurrence group (NR-group, n=40), there was no significant difference in left atrial dimension, duration of PAF, or additional RF applications with PVI at the 1st procedure. At the 2nd procedure, PV re-connection was observed in significantly fewer patients in the R-group (17/21 ; 80.9%) than the NR-group (39/40 ; 97.5%, p=0.025). Non-PV foci were similarly observed in both groups (R-group : 14/21 ; 66.7% vs NR-group : 17/40 ; 42.5%), but the elimination of non-PV foci was significantly higher in the NR-group (15/17 ; 88%) than the R-group (7/14 ; 50%, p=0.019). Conclusion : These data indicated that the non-PV foci was an important factor for the recurrence of AF/AF even after 2nd procedure in patients with PAF. Aggressive efforts to provoke and eliminate non-PV foci in any session could improve the results of catheter ablation for PAF.

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We here present the case of an 81-year-old woman with poorly controlled hyperthyroidism and transient atrioventricular block. The patient had previously been attending a nearby hospital where she had been prescribed methimazole for hyperthyroidism, but this medication had been stopped 4 months prior to her presentation to our institution because she had become euthyroid. On the day of admission to our institution, she presented to a nearby hospital, her chief symptom being dyspnea on exertion. An electrocardiogram showed complete atrioventricular block and atrial fibrillation and she was referred to our hospital. Although complete atrioventricular block was present at the time of admission, it resolved spontaneously immediately thereafter. Further tests were performed before inserting a cardiac pacemaker. Because she was in a hyperthyroid state, methimazole was recommenced. Cardiac catheter tests showed no coronary artery stenosis, aortic valve stenosis, or right heart overload, and an electrophysiology study showed no conduction abnormality. The patient's thyroid function gradually improved and atrioventricular block did not recur. She was discharged without a cardiac pacemaker. Hyperthyroidism should be considered as a possible cause of complete atrioventricular block, which may be completely reversible with restoration of a euthyroid state.

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A 24-year-old male was referred to a hospital after a medical check-up revealed frequent premature ventricular contractions and non-sustained ventricular tachycardias. He was diagnosed with arrhythmogenic right ventricular cardiomyopathy (ARVC) and treated with a beta-blocker and limited exercise. In 4 years, the patient suddenly collapsed due to ventricular fibrillation right after playing basketball. Although a bystander performed CPR and electrical defibrillation was performed repeatedly, the patient died. An autopsy revealed, ARVC. We then, performed a genetic analysis and indentified a mutation of PKP2 (c.C2119T, p. Q707X). Plakophilin-2 (PKP2) is an essential protein forming the desmosomal complex, and disruption of desmosome leads to the loss of cell to cell connection, which in turn causes ARVC. In this short report, we present an autopsy case of ARVC caused by a mutation of PKP2.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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