Aims : Acquired long QT syndrome（aLQTS）exhibits QT prolongation and Torsades-de-Pointes ventricular tachycardia triggered by drugs, hypokalemia or bradycardia. Sometimes QTc remains prolonged despite elimination of triggers, suggesting the presence of an underlying genetic substrate. We assessed the prevalence of mutations in major LQTS genes in aLQTS subjects and their probability of being carriers of a disease-causing genetic variant based on clinical factors. We screened for the 5 major LQTS genes among 188 aLQTS probands（55±20 years, 140 females）from Japan, France and Italy. Based on control QTc（without triggers）, subjects were designated “true aLQTS”（QTc within normal limits）or “unmasked cLQTS”（all others）and compared for QTc and genetics with 2379 members of 1010 genotyped congenital long-QT-syndrome（cLQTS）families. Cardiac symptoms were present in 86％ of aLQTS subjects. Control QTc of aLQTS was 453±39msec, shorter than in cLQTS（478±46msec, p＜0.001）and longer than in non-carriers（406±26msec, p＜0.001）. In 53（28％）aLQTS subjects, 47 disease-causing mutations were identified. KCNQ1 mutations were much less frequent than KCNH2 （20％［95％CI 7％―41％］ vs. 64％［95％CI 43％―82％］, p＜0.01） in “true aLQTS” than in cLQTS. A clinical score based on control QTc＞440msec, age＜40 years, and symptoms allowed identification of patients more likely to carry LQTS mutations. A third of aLQTS patients carry cLQTS mutations, those on KCNH2 being more common. The probability of being a carrier of cLQTS disease-causing mutations can be predicted by simple clinical parameters, thus allowing possibly cost-effective genetic testing leading to cascade screening for identification of additional at-risk family members.

Knowing the anatomy of the coronary vein（CV）and left phrenic nerve（LPN） is important for successful LV lead implantation. The aim of this study was to evaluate the accuracy of three-dimensional（3D）cardiac non-contrast computed tomography. We included 20 cases in this study. 3D image of CV was compared with intraoperative CV venogram, and accuracy of 3D image of LPN was assessed by checking if the site of phrenic nerve stimulation equaled 3D image of LPN. 3D image of CV was same as CV venogram in 19/20 cases. Phrenic nerve stimulation was observed in 10 cases, and 3D image of LPN matched as the site of phrenic nerve stimulation. As a result, we concluded that anatomical evaluation by cardiac non-contrast computed tomography is accurate. When we implant a CRT device, 3D image of CV and LPN constructed from non-contrast CT are usable tools through which we can obtain anatomical information before CRT implantation.

Background : Since fluoroscopy time for atrial fibrillation（AF）catheter ablation procedure is usually longer than for other tachyarrhythmia, greater attention should be paid to the occurrence of tissue reactions such as skin injury. Recently, in addition to radiofrequency ablation（RFA）, cryoballoon ablation （CBA） and hotballoon ablation （HBA） have been performed. The aim of this study was to evaluate the difference in entrance skin dose（ESD）due to the procedure in patients who received AF ablation. Methods : The study population consists of 342 consecutive patients（233 male and 109 female）who received ablation for AF at Nagoya Daini Red Cross Hospital from May 2017 to February 2018. Collected data included gender, age, fluoroscopy time, the number of cine frames, reference air-kerma（RAK）, dose area product and type of AF. ESD was evaluated by use of RAK displayed on angiography system. Results : Mean fluoroscopy time, mean number of cine frames, and mean ESD during AF ablation were 53.1minutes, 388frames and 303.3mGy, respectively. The approach for pulmonary vein isolation （PVI） which required the longest fluoroscopic time was RFA（60.1minutes）, followed by HBA（52.5minutes）, CBA（48.2minutes）. On the other hand, the approach for PVI which showed the highest ESD was HBA（427.4mGy）, followed by CBA（306.8mGy）, and RFA（281.7mGy）. Despite the fact that the longest fluoroscopy times in the left anterior oblique projection were up to 79.4minutes, the evaluated ESD values were under the threshold of 2Gy for acute skin injury. Conclusions : Previously, PVI for AF ablation sometimes caused radiation skin injury, but as a result of recent advances in various dose reduction technologies, radiation exposure has been greatly reduced.

Background : About 50, 000 cardiac devices are implanted every year in Japan, but there is no uniform policy on how to handle cardiac implantable devices（CID）before cremating persons with CID. More and more family physicians have been attending patients’ deathbed at their home. If it were possible to cremate a deceased person without removing a CID, it would eliminate confusion about whether to remove a CID or not and reduce the risk of infection when a doctor takes a CID out. Purpose : To study current CID－handling policies at all listed crematories in the Chugoku district in Japan. Method : A total of 162 crematories（76 administrators）in 5 prefectures（Tottori, Shimane, Okayama, Hiroshima and Yamaguchi）in the Chugoku district were surveyed by email, fax and/or telephone. Result : Of all crematories in the Chugoku district, 9 crematories（5.6％）（8 administrators）refuse to cremate a body with a CID. A CID must be removed before cremation. Ninety-three crematories（57.4％）（42 administrators）accept a body with a CID with advance notification, but they prefer CIDs to be removed if possible. Sixty crematories（37.0％）（27 administrators）accept a body with a CID with advance notification alone. Conclusion：In the Chugoku district, 94.4％ of crematories will cremate a body with a CID. However, informing crematory staff that a deceased person has a CID beforehand is required and raising awareness of this procedure may be necessary.