Extensive Preferential Pathway Ablation for the Elimination of Premature Ventricular Contractions Arising from the Right Ventricular Outflow Tract

AbstractA 76 y/o women presented with 2 different types of premature ventricular contractions (VPCs 1 and 2) arising from the right ventricular outflow tract (RVOT). Catheter ablation (CA) eliminated PVC1 at the earliest activation site (EAS), but thereafter another PVC morphology (PVC3) appeared. Small potentials preceding the local potential were broadly exhibited from the RVOT’s supero-anterior region to the EAS during PVC3. Point CA targeting such prepotentials failed. Transverse-linear CA with a line connecting sites with such pre-potentials eliminated both PVCs 3 and 2. In cases with broadly spreading preferential pathways, extensive CA might be needed to eliminate the PVCs

National survey of catheter ablation for atrial fibrillation: The Japanese catheter ablation registry of atrial fibrillation (J-CARAF)

AbstractTo assess the current status of atrial fibrillation (AF) ablation in Japan, the Japanese Heart Rhythm Society (JHRS) instituted a national registry, the Japanese Catheter Ablation Registry of AF (J-CARAF).MethodsUsing an online questionnaire, the JHRS invited electrophysiology centers in Japan to voluntarily and retrospectively register data regarding the AF ablation procedures performed in September, 2011.ResultsA total of 128 centers submitted data regarding AF ablation procedures in 932 patients (age 62.1±10.4 years; male 76.8%; paroxysmal AF 65.7%, CHADS2 score 1.0±1.0). The majority received oral anticoagulant therapy during and following the procedure (68.9% and 97.5%, respectively). Pulmonary vein isolation (PVI) was performed in 97.5% of the patients; ipsilateral encircling PVI was the preferred technique (79.7%). Three-dimensional (3D) mapping systems and irrigated-tip catheters were used in 94.8% and 87.7% of the procedures, respectively. Ablation methods other than PVI were performed in 78.8% of all the patients and 73.5% of the patients with paroxysmal AF. Acute complications were reported in 6.2% of the patients, but no early deaths were recorded.ConclusionsIpsilateral encircling PVI, using 3D mapping and irrigated-tip catheters, is the standard AF ablation method in Japan. However, adjunctive ablations were performed frequently, even in patients with paroxysmal AF

Superiority of Biphasic Over Monophasic Defibrillation Shocks Is Attributable to Less Intracellular Calcium Transient Heterogeneity

ObjectivesThe purpose of this study was to test the hypothesis that superiority of biphasic waveform (BW) over monophasic waveform (MW) defibrillation shocks is attributable to less intracellular calcium (Cai) transient heterogeneity.BackgroundThe mechanism by which BW shocks have a higher defibrillation efficacy than MW shocks remains unclear.MethodsWe simultaneously mapped epicardial membrane potential (Vm) and Cai during 6-ms MW and 3-ms/3-ms BW shocks in 19 Langendorff-perfused rabbit ventricles. After shock, the percentage of depolarized area was plotted over time. The maximum (peak) post-shock values (VmP and CaiP, respectively) were used to measure heterogeneity. Higher VmP and CaiP imply less heterogeneity.ResultsThe defibrillation thresholds for BW and MW shocks were 288 ± 99 V and 399 ± 155 V, respectively (p = 0.0005). Successful BW shocks had higher VmP (88 ± 9%) and CaiP (70 ± 13%) than unsuccessful MW shocks (VmP 76 ± 10%, p < 0.001; CaiP 57 ± 8%, p < 0.001) of the same shock strength. In contrast, for unsuccessful BW and MW shocks of the same shock strengths, the VmP and CaiP were not significantly different. The MW shocks more frequently created regions of low Cai surrounded by regions of high Cai (post-shock Cai sinkholes). The defibrillation threshold for MW and BW shocks became similar after disabling the sarcoplasmic reticulum (SR) with thapsigargin and ryanodine.ConclusionsThe greater efficacy of BW shocks is directly related to their less heterogeneous effects on shock-induced SR Ca release and Cai transients. Less heterogeneous Cai transients reduces the probability of Cai sinkhole formation, thereby preventing the post-shock reinitiation of ventricular fibrillation

腹膜および胸膜悪性中皮腫におけるEGFR発現の比較

An evaluation of epidermal growth factor receptor (EGFR) phenotypic expression in malignant pleural and peritoneal mesothelioma was undertaken, using immunohistochemical (IHC) and fluorescence in situ hybridization (FISH) analysis. Thirty-eight malignant mesothelioma (MM) specimens were subjected to IHC staining and FISH to evaluate the expression of EGFR protein and gene status. Overall positive IHC reaction was detected in 20/38 (53%) cases, in 11/22 (50%) pleural MM, and in 9/16 (56%) peritoneal MM. Our study confirmed that EGFR membranous expression is a common feature in MM, but not in benign mesothelial lesion. Thirty-seven cases did not show a gene copy number gain. Only one case showed a copy number gain. The protein overexpression of EGFR was not related to a gene copy number gain.博士（医学）・乙第1299号・平成24年5月28日© 2012 The Authors. Pathology International© 2012 Japanese Society of Pathology and Blackwell Publishing Asia Pty Ltd

Prognostic significance of nonsustained ventricular tachycardia in patients receiving cardiac resynchronization therapy for primary prevention: Analysis of the Japan cardiac device treatment registry database

BackgroundWhether nonsustained ventricular tachycardia (NSVT) is a marker of increased risk of sustained ventricular tachyarrhythmias (VTAs) remains to be established in patients receiving cardiac resynchronization therapy with a defibrillator (CRT‐D) for primary prevention.MethodsAmong the follow‐up data of the Japan cardiac device treatment registry (JCDTR) with an implantation date between January 2011 and August 2015, information regarding a history of NSVT before the CRT‐D implantation for primary prevention had been registered in 269 patients. Outcomes were compared between two groups with and without NSVT: NSVT group (n = 179) and No NSVT group (n = 90).ResultsThere was no significant difference with regard to age, gender, and NYHA class between the two groups. Left ventricular ejection fraction (LVEF) was 25.6% in the NSVT group and 28.0% in the No NSVT group (P = .046). The rate of appropriate therapy at 24 months was 26.0% and 18.4% in the NSVT and No NSVT groups (P = .22), respectively. Survival free from heart failure death was reduced in the NSVT group, as compared with the No NSVT group, with the rate of 90.2% vs 97.2% at 24 months (P = .030). A multivariate analysis identified a history of NSVT, anemia, and no use of angiotensin‐converting enzyme inhibitor (ACEI) or angiotensin‐receptor blocker (ARB) as predictors of heart failure death.ConclusionsNSVT appears to be a surrogate marker of severe heart failure rather than a substrate for subsequent sustained VTAs in patients with CRT‐D for primary prevention

Extensive Preferential Pathway Ablation for the Elimination of Premature Ventricular Contractions Arising from the Right Ventricular Outflow Tract

A 76 y/o women presented with 2 different types of premature ventricular contractions (VPCs 1 and 2) arising from the right ventricular outflow tract (RVOT). Catheter ablation (CA) eliminated PVC1 at the earliest activation site (EAS), but thereafter another PVC morphology (PVC3) appeared. Small potentials preceding the local potential were broadly exhibited from the RVOT’s supero-anterior region to the EAS during PVC3. Point CA targeting such prepotentials failed. Transverse-linear CA with a line connecting sites with such pre-potentials eliminated both PVCs 3 and 2. In cases with broadly spreading preferential pathways, extensive CA might be needed to eliminate the PVCs

Trends and determinant factors in the use of cardiac resynchronization therapy devices in Japan : Analysis of the Japan cardiac device treatment registry database

Background: The choice of cardiac resynchronization therapy device, with (CRT-D) or without (CRT-P) a defibrillator, in patients with heart failure largely depends on the physician's discretion, because it has not been established which subjects benefit most from a defibrillator. Methods: We examined the annual trend of CRT device implantations between 2006 and 2014, and evaluated the factors related to the device selection (CRT-D or CRT-P) for primary prevention of sudden cardiac death in patients with heart failure by analyzing the Japan Cardiac Device Treatment Registry (JCDTR) database from January 2011 and August 2015 (CRT-D, n=2714; CRT-P, n=555). Results: The proportion of CRT-D implantations for primary prevention among all the CRT-D recipients was more than 70% during the study period. The number of CRT-D implantations for primary prevention reached a maximum in 2011 and decreased gradually between 2011 and 2014, whereas CRT-P implantations increased year by year until 2011 and remained unchanged in recent years. Multivariate analysis identified age (odds ratio [OR] 0.92, 95% confidence interval [CI] 0.90-0.95, P < 0.0001), male sex (OR 1.99, 95% CI 1.28-3.11, P < 0.005), reduced left ventricular ejection fraction (LVEF) (OR 0.96, 95% CI 0.94-0.98, P < 0.0001), and non-sustained ventricular tachycardia (NSVT) (OR 2.85, 95% CI 1.87-4.35, P < 0.0001) as independent factors favoring the choice of CRT-D. Conclusions: Younger age, male sex, reduced LVEF, and a history of NSVT were independently associated with the choice of CRT-D for primary prevention of sudden cardiac death in patients with heart failure in Japan

Effect of cardiac rehabilitation on the renal function in chronic kidney disease - Analysis using serum cystatin-C based glomerular filtration rate

Background: Whether an individually determined appropriate level of cardiac rehabilitation (CR) has a favorable effect on the renal function still remains unclarified. The aim of this study was to confirm the effect of CR on the estimated glomerular filtration rate (eGFR) using cystatin C, which is known to be unaffected by physical exercise. Methods: The study population was comprised of 86 patients (61 males; average age 74 y/o) with a lower-moderate level of chronic kidney disease (CKD) who was admitted to our hospital for treatment of cardiovascular disease (CVD) and who participated in our 3-month CR program. The exercise capacity was assessed by cardiopulmonary exercise testing (CPX) and the eGFR was measured by a formula based on the serum cystatin C concentration (eGFRcys) in each patient both at the beginning and end of the CR. Results: In the CVD patients with CKD, both the peak oxygen uptake (VO2) and peak work rate (WR) improved significantly after CR (15.0 ± 3 to 15.8 ± 3 ml/min/kg, p = 0.002. 65.5 ± 21 to 70.2 ± 25 W, p = 0.001). Regarding the renal function, the eGFRcys improved (45.2 ± 11 to 47.3 ± 13 ml/min/1.73 m2, p = 0.023), however, the eGFR assessed by the serum creatinine (eGFRcr) did not improve after CR (45.1 ± 12 to 44.9 ± 13 ml/min/1.73 m2, p = 0.834). Conclusions: In CVD patients, a novel CR program significantly improved the exercise capacity. Further, CR was shown to have a favorable effect on the renal function when it was estimated by the eGFRcys. Keywords: Cardiac rehabilitation, Chronic kidney disease, Cardiovascular disease, Cystatin C, Estimated glomerular filtration rate, Exercise capacit

Cardiac fibrosis as a determinant of ventricular tachyarrhythmias

Animal and emerging clinical studies have demonstrated that increased ventricular fibrosis in a setting of reduced repolarization reserve promotes early afterdepolarizations (EADs) and triggered activity that can initiate ventricular tachycardia and ventricular fibrillation (VT/VF). Increased ventricular fibrosis plays a key facilitatory role in allowing oxidative and metabolic stress-induced EADs to manifest as triggered activity causing VT/VF. The lack of such an arrhythmogenic effect by the same stressors in normal non-fibrotic hearts highlights the importance of fibrosis in the initiation of VT/VF. These findings suggest that antifibrotic therapy combined with therapy designed to increase ventricular repolarization reserve may act synergistically to reduce the risk of sudden cardiac death