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Background Recurrence of atrial fibrillation (AF) after pulmonary vein isolation (PVI) is associated with left atrial (LA) remodeling; however, its association with right atrial (RA) remodeling remains unclear. Objective This study aimed to identify whether RA structural remodeling could predict recurrence of AF after PVI. Methods This study prospectively analyzed 245 patients with AF who had undergone PVI. RA and LA volumes were determined by contrast‐enhanced computed tomography. Atrial structural remodeling was defined as an atrial volume of ≥110 mL according to previous reports and receiver operating characteristic curve analysis. Results After excluding 32 patients, 213 patients were analyzed. During a follow‐up period of 12 months, 41 patients (19%) demonstrated atrial arrhythmia recurrence after PVI. With the Cox proportional‐hazards model, RA structural remodeling was the only predictor of arrhythmia recurrence (hazard ratio, 1.012; 95% confidence interval 1.003‐1.021; P = .009). Kaplan–Meier analysis showed that arrhythmia recurrence was more frequent in the RA structural remodeling group compared with the group without RA remodeling (log‐rank, P, A greater incidence of recurrence was observed in the presence of RA structural remodeling regardless of the AF type. RA structural remodeling was a useful predictor of clinical outcomes after PVI.

Aim: Arterial stiffness results in elevated left ventricular filling pressure and can promote atrial remodeling due to chronic pressure overload. However, the impact of arterial stiffness on the process of atrial remodeling in association with atrial fibrillation (AF) has not been fully evaluated. Methods: We enrolled 237 consecutive patients diagnosed with AF who had undergone ablation; data from 213 patients were analyzed. Cardio-ankle vascular index (CAVI) was used as a marker of arterial stiffness. The left atrial (LA) and right atrial (RA) volumes were determined by computed tomography imaging; atrial conduction and voltage amplitude were evaluated using a three-dimensional electromapping system used to guide the ablation procedure. Result: In univariate analysis, CAVI significantly correlated with atrial structural and electrical remodeling (LA volume index, r =0.297, P =0.001; RA volume index, r =0.252, P =0.004; LA conduction velocity, r =0.254, P = 0.003; LA mean voltage, r =−0.343, P =0.001, RA mean voltage; r =−0.245, P =0.015). Multivariate regression analysis revealed that CAVI and plasma levels of N-terminal B-type natriuretic peptide were independent determinants of LA and RA remodeling, respectively. On the other hand, age and LA conduction velocity were independent variables with respect to CAVI. Age-adjusted CAVI was highest in long-standing persistent AF when compared with measures of persistent or paroxysmal AF. Conclusion: CAVI was closely associated with biatrial remodeling in patients diagnosed with AF. These results suggest that arterial stiffness may play a significant role with respect to disease progression.

Atrial remodeling associated with atrial fibrillation (AF) and sleep apnea is well known. Although sleep apnea is known to be associated with left atrial (LA) remodeling, its association with right atrial (RA) remodeling remains unclear. The study aimed to investigate the effect of sleep apnea on RA remodeling.We enrolled 141 AF patients who had undergone ablation. Sleep study results were evaluated using a portable sleep apnea test device. RA and LA volumes were determined by computed tomography (CT), and atrial structural remodeling was defined as atrial volume on CT≥110mL according to previous reports. The atrial substrate was evaluated by three-dimensional electroanatomical mapping.After excluding 30 patients who received more than one catheter ablation or who could not receive enhanced CT, 111 patients were finally analyzed. The patients were classified into four groups according to the presence of RA and/or LA enlargement. Significant differences in AF type, N-terminal pro B-type natriuretic peptide (NT-proBNP) levels, and apnea-hypopnea index (AHI) were observed among the four groups. In univariate analysis, AHI values correlated with NT-proBNP levels (r=0.293, p=0.002), left ventricular ejection fraction (r=-0.198, p=0.044), LA volume (r=0.370, p0.001), and RA volume (r=0.465, p0.001). Multiple regression analysis showed that AHI was an independent predictor of increased RA volume, and LA was excluded as a multiple risk factor in AHI. AF type-adjusted AHI levels correlated with RA volume, and RA remodeling correlated with the percentage of LA low-voltage area.Sleep apnea was strongly associated with RA structural remodeling regardless of paroxysmal and non-paroxysmal AF, and this relationship was more prominent than the effect of LA. Our results suggest that the association between sleep apnea and RA dilatation should be given attention.

Background Radiofrequency catheter ablation (RFCA) is an effective therapy for atrial fibrillation (AF). However, it the problem of AF recurrence remains. This study investigates whether a deep convolutional neural network (CNN) can accurately predict AF recurrence in patients with AF who underwent RFCA, and compares CNN with conventional statistical analysis.Methods and Results:Three-hundred and ten patients with AF after RFCA treatment, including 94 patients with AF recurrence, were enrolled. Nine variables are identified as candidate predictors by univariate Cox proportional hazards regression (CPH). A CNNSurv model for AF recurrence prediction was proposed. The model's discrimination ability is validated by a 10-fold cross validation method and measured by C-index. After back elimination, 4 predictors are used for model development, they are N-terminal pro-BNP (NT-proBNP), paroxysmal AF (PAF), left atrial appendage volume (LAAV) and left atrial volume (LAV). The average testing C-index is 0.76 (0.72-0.79). The corresponding calibration plot appears to fit well to a diagonal, and the P value of the Hosmer-Lemeshow test also indicates the proposed model has good calibration ability. The proposed model has superior performance compared with the DeepSurv and multivariate CPH. The result of risk stratification indicates that patients with non-PAF, higher NT-proBNP, larger LAAV and LAV would have higher risks of AF recurrence. Conclusions The proposed CNNSurv model has better performance than conventional statistical analysis, which may provide valuable guidance for clinical practice.

A healthy 73-year-old woman unpredictably developed Takotsubo cardiomyopathy syndrome (TTS) during Holter-electrocardiogram (ECG) recording. Thus, the complete chronological ECG data on the actual onset day of TTS were obtained. Many heart rate variability (HRV) parameters, including the low-frequency components (LF) and the high-frequency components (HF), on the actual onset day and in the healing phase were calculated. The interesting facts on the actual onset day were that the suppression of both LF and HF appeared earlier than the changes of the ECG waveform; and the LF/HF ratio remained within the normal range, although both LF and HF were markedly suppressed. The abnormality on the actual onset day was clear compared with the healing phase. It is noteworthy to obtain the chronological ECG data on the actual onset day of TTS in a healthy patient. The present data are unique in terms of being analyzed on the actual onset day. Although the HRV parameters, including LF and HF, were obviously abnormal, there is some skepticism about using HRV parameters as indices of cardiac autonomic activity. In the present case, it was concluded that the abnormality of cardiac autonomic activity contributed to the onset of TTS. These data are unlikely to ever be replicated, and we hope that this report helps elucidate the TTS mechanism.

Background Atrial fibrillation (AF) induces functional mitral regurgitation (FMR) and tricuspid regurgitation (FTR) during atrial remodeling. FMR and FTR are associated with AF prognosis, but the effects for AF recurrence after ablation have not been determined conclusively. Methods Two hundred thirty nine patients who underwent AF ablation were enrolled. Forty five patients were excluded. In total, 194 patients were analyzed. FMR and FTR were assessed by echocardiography. The left atrial volume index (LAVI) was evaluated by contrast-enhanced computed tomography. Results Significant FMR and moderate FTR were observed in 15 (7.7%) and in 25 (12.9%) patients, respectively. The severity of tricuspid regurgitation (TR) significant correlated with age, NT-proBNP, and LAVI. During a 13.4 month follow-up period of, 39 patients (20.1%) demonstrated AF recurrence. In the Cox proportional-hazards model, E/e’, FTR, and LAVI, were termed as predictor factors of AF recurrence (E/e’. hazard ratio [HR] = 1.117; P = 0.019, significant FTR. HR = 4.679; P = 0.041, LAVI. HR = 1.057; P = 0.003). Kaplan–Meier analysis showed that AF recurrence was more frequent in FTR compared with the nonsignificant FTR cases (log-rank, P = 0.001). Although survival analysis showed no difference with or without FMR, the presence of FMR and FTR was strongly associated with high-AF recurrence (log-rank, P = 0.004). Conclusions AF recurrence was associated with E/e’, LAVI, and extensive FTR. Specifically, the combination of FTR and FMR markedly worsens the AF prognosis.

There is increased interest in creating high-power short duration (HPSD) ablation lesions in the field of atrial fibrillation (AF) radiofrequency ablation (RFA). We evaluated the lesion characteristics and collateral damage using two separate RFA protocols setting (HPSD: 50 W and 7 s vs control: 25 W and 30 s) in vitro model. Sixteen freshly killed porcine hearts were obtained, and the atrium and ventricle slabs were harvested for ablation. The each slabs were placed in a tissue bath with circulating 0.9% NaCl at maintained temperature 37 °C. RFA was performed with 4 mm tip irrigated force sensing catheter. All lesions were ablated under recording the electrical parameters using with Ensite Navx system (St. Jude Medical, St. Paul, Minnesota). After RFA, lesion characteristics were assessed for each lesion. Thirty-five lesions were made for each ablation protocol (total 70 lesions for analysis). Ablation parameters were similar between two groups (HPSD vs control; impedance drop (Ω): 34.2 ± 13.1 vs 36.1 ± 8.65 P = 0.49, contact force (g): 13.9 ± 4.37 vs 14.6 ± 5.09, P = 0.51, lesion size index: 4.8 ± 0.52 vs 4.73 ± 0.59, P = 0.62). Although the lesion volume was similar, the HPSD ablation creates wider but more shallower lesions compared to control group (HPSD vs control; lesion volume: 29.6 ± 18.1 mm3 vs 35.5 ± 17.1 mm3 P = 0.16, lesion diameter: 4.98 ± 0.91 mm vs 4.45 ± 0.74 mm P = 0.0095, lesion depth: 2.2 ± 0.76 mm vs 2.8 ± 1.56 mm P = 0.046). Of these, 38 lesions were assessed for adjacent tissue damage and adjacent tissue damages were more frequent seen in control group (HPSD vs control; 1/19 (5.26%) vs 6/19 (31.5%), P = 0.036). Effective lesions were made with HPSD, thereby reducing RFA procedure time. Although the lesion volume was similar between two groups, collateral damage was less seen in HPSD group attributed by lesion characteristics.

A 78-year-old male with a history of a cardiac embolic stroke due to persistent AF and cerebral bleeding (CHADS2 score 4, HAS-BLED score 4) was referred to our hospital to implant a left atrial appendage (LAA) closure (LAAC) device. A trans esophageal echocardiography was performed and a high echoic lesion that was difficult to differentiate the spontaneous echo contrast or thrombus was found in the LAA cavity. After isoproterenol infusion, a high echoic lesion disappeared and we confirmed that it was not an LAA thrombus. Successful LAAC device implantation was performed without any thromboembolic events.

Low sodium levels are strongly associated with poor prognosis in acute heart failure (AHF); however, the prognostic impact of the sodium level trajectory overtime has not been determined. A secondary analysis of the AQUAMARINE study in which patients with AHF and renal impairment were randomized to receive either tolvaptan or conventional treatment was performed. Sodium levels were evaluated at the baseline and at 6, 12, 24, and 48 h. We defined 'sodium dipping' as sodium level falling below the baseline level at any time point. The primary endpoint was the combined event of all-cause death and heart failure rehospitalization during follow-up. The analysis included 184 patients with a median follow-up of 21.1 months. Sodium levels more steeply increased during the 48 h in patients without events as compared to sodium levels in patients with events (P = 0.018 in linear-mixed effect model). The sodium dipping group (n = 100; 54.3%) demonstrated significantly less urine output, less body weight reduction, and poorer diuretic response within 48 h compared to the non-dipping group. The sodium dipping group was also significantly associated with a low combined-event-free survival after adjustment for other prognostic factors (HR 1.97; 95% CI 1.06-3.38; P = 0.033). The trajectory of sodium levels during the acute phase is associated with the prognosis of patients with AHF independently of the baseline sodium level.

Background Poor response to diuretics is associated with worse prognosis in patients with acute heart failure (AHF). We hypothesized that treatment with tolvaptan improves diuretic response in patients with AHF. Methods We performed a secondary analysis of the AQUAMARINE open-label randomized study in which a total of 217 AHF patients with renal impairment (eGFR

Background There has been no report about outcome of pitavastatin versus atorvastatin therapy in high-risk patients with hypercholesterolemia. Methods Hypercholesterolemic patients with one or more risk factors for atherosclerotic diseases (n = 664, age = 65, male = 54%, diabetes = 76%, primary prevention = 74%) were randomized to receive pitavastatin 2 mg/day (n = 332) or atorvastatin 10 mg/day (n = 332). Follow-up period was 240 weeks. The primary end point was a composite of cardiovascular death, sudden death of unknown origin, nonfatal myocardial infarction, nonfatal stroke, transient ischemic attack, or heart failure requiring hospitalization. The secondary end point was a composite of the primary end point plus clinically indicated coronary revascularization for stable angina. Results The mean low-density lipoprotein cholesterol (LDL-C) level at baseline was 149 mg/dL. The mean LDL-C levels at 1 year were 95 mg/dL in the pitavastatin group and 94 mg/dL in the atorvastatin group. There were no differences in LDL-C levels between both groups, however, pitavastatin significantly reduced the risk of the primary end point, compared to atorvastatin (pitavastatin = 2.9% and atorvastatin = 8.1%, HR, 0.366; 95% CI 0.170–0.787; P = 0.01 by multivariate Cox regression) as well as the risk of the secondary end point (pitavastatin = 4.5% and atorvastatin = 12.9%, HR = 0.350; 95%CI = 0.189–0.645, P = 0.001). The results for the primary and secondary end points were consistent across several prespecified subgroups. There were no differences in incidence of adverse events between the statins. Conclusion Pitavastatin therapy compared with atorvastatin more may prevent cardiovascular events in hypercholesterolemic patients with one or more risk factors for atherosclerotic diseases despite similar effects on LDL-C levels.

A 49-year-old woman was admitted to our hospital because of repeated loss of consciousness. On arrival, she was in cardiopulmonary arrest associated with arrhythmia of Torsades de pointes, and recovered from it after cardiopulmonary resuscitation and defibrillation. The administration of a β-blocker and amiodarone was initiated to prevent ventricular tachycardia. On day 2, coronary angiography revealed non-obstructive coronary artery, and left ventriculography (LVG) exhibited hypokinesis in the anterior and apical wall. On day 20, an acetylcholine provocation test revealed a multivessel vasospasm, and LVG showed "spade-shaped left ventricle" in end-diastole because of apical hypertrophy. Transthoracic echocardiography (TTE) also showed apical wall thickness. Subsequent apical wall thickness gradually decreased and returned to normal on day 51 as observed on the TTE. Thus, we report a case of transient apical hypertrophy associated with coronary vasospasm, which was demonstrated by both the TTE and LVG. .

Background Renal dysfunction is a common comorbidity in acute heart failure (AHF) patients. The prognostic significance of early treatment with tolvaptan in AHF patients complicated with renal dysfunction has not been elucidated. Methods Post hoc analysis was performed on a randomized clinical study for prespecified prognostic endpoints and prespecified subgroups. 217 AHF patients with renal dysfunction (eGFR 15 to 60mL/min/1.73m 2 ) were randomized within 6h from hospitalization to either tolvaptan treatment for 2days or conventional treatment. The primary outcome was the combined endpoint of all-cause death and HF readmission. Results During follow-up (636days, median) 99 patients experienced combined endpoint and 53 patients died. There was no significant difference in event-free survival rate for either the combined events (Log-rank: P=0.197) or all-cause death (Log-rank: P=0.894) between tolvaptan and conventional groups. In prespecified subgroup analysis, in patients whose BUN/creatinine ratio was above the median (>20), tolvaptan significantly reduced the risk of combined events (HR: 0.52, 95% CI: 0.30–0.91, P=0.021) with a significant interaction (P value for interaction=0.045). Likewise, in patients whose eGFR was 30mL/min/1.73m 2 or above, tolvaptan reduced the risk of combined events (HR: 0.54, 95% CI: 0.32–0.90, P=0.017) with a significant interaction (P value for interaction=0.015). Conclusion Short-term use of tolvaptan in acute-phase in AHF with renal dysfunction showed a neutral effect on prognosis. Patients with relatively preserved renal function and relatively high BUN/creatinine ratios are potentially favorable subgroups for treatment with tolvaptan.

A 70-years-old male with a history of hypertension and drug resistant paroxysmal atrial fibrillation (AF) presented to our hospital for catheter ablation to his symptomatic AF. He had no prior surgical or percutaneous procedure to close or exclude the left atrial appendage (LAA). A transesophageal echocardiography (TEE) was performed to rule out intra-cardiac thrombus prior to the ablation procedure. Although the TEE imaging at multiple acquisition angles was obtained, the LAA could not be visualized and an absence of the LAA was suspected. An absence of the LAA was confirmed using cardiac computed tomography (CT), which included 3D reconstruction. Additionally, the LAA was not visualized with left atrium (LA) angiography. During the ablation procedure, 3D voltage mapping in LA was created and no low voltage area or abnormal potential was recorded around the usual root location of the LAA. Successful electrical pulmonary vein isolation was achieved with no major complications. After six months of follow-up, the patient remained in sinus rhythm without any antiarrhythmic drugs and showed no related clinical symptoms. He stopped his anticoagulation therapy due to lack of evidence of AF recurrence and an absence of LAA. Multimodality imaging allowed us to identify the congenital absence of LAA.

A 33-year-old male was referred to our institute with acute heart failure. The patient was found to have a unicuspid aortic valve (UAV) and severe aortic stenosis. He had been followed at a local university hospital during childhood. However, he stopped visiting the outpatient clinic after becoming an adult. His condition subsequently worsened, and he ultimately presented to our hospital with cardiogenic shock. In Japan, some adult congenital heart disease (ACHD) patients continue to be followed by pediatric cardiologists, though the patterns of practice are variable. This report describes the case of a patient who became lost to follow-up in early adulthood. We thus focus on this ACHD case as an example of the effects of inadequate communication among doctors and the need to establish better ACHD management protocols for treating this patient population.

Chronic total occlusion (CTO) lesions are a challenging issue. When dealing with complex CTO lesions in patients undergoing percutaneous coronary intervention (PCI), it is important to evaluate not only the CTO lesion itself but also atherosclerotic lesions of the whole coronary artery tree. The utility of the SYNTAX (Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery Trial) score in patients with CTO undergoing PCI is unclear.This retrospective study included 304 consecutive patients with CTO lesions who underwent PCI. Primary endpoints were procedural failure and major adverse cardiac events (MACE) within 30 days. The SYNTAX and J-CTO (Multicenter CTO Registry in Japan) scores were assessed before the procedures, and patients were divided into two groups according to SYNTAX criteria: high ( 22; n = 158) and low (≤ 22; n = 146) SYNTAX scores.Procedural success was achieved in 252 patients (82.9 %). Patients with a high SYNTAX score had significantly lower procedural success than those with a low SYNTAX score (74.7 % versus 91.8 %, p 0.0001). There were 13 MACE (8.2 %) in patients with high SYNTAX scores and two MACE (1.4 %) in those with low scores. The SYNTAX and J-CTO scores had odds ratios of 3.33 (95 %CI, 1.44-7.74) and 3.64 (95 %CI, 1.24-10.66) for procedural failure. A higher SYNTAX score ( 22) was also an independent predictor of 30-day MACE after PCI (odds ratio = 4.80, 95 %Cl 1.03-22.42).The SYNTAX score is predictive of procedural failure, as is the J-CTO score. Furthermore, a higher SYNTAX score is strongly associated with an increased risk of 30-day MACE. The SYNTAX score is useful for clinical decision making when treating patients with complex CTO lesions.

Introduccion y objetivos En estudios previos se ha descrito que la intervencion coronaria aplicada a lesiones complejas presenta una correlacion independiente con las hemorragias mayores. La puntuacion SYNTAX es un instrumento angiografico utilizado para evaluar el grado de complejidad de las enfermedades arteriales coronarias. El objetivo de este estudio es evaluar la capacidad de la puntuacion SYNTAX para predecir hemorragias mayores tras el implante de stents liberadores de farmacos. Metodos Se analizo a un total de 722 pacientes sometidos a implante de stents liberadores de farmacos de una poblacion de pacientes consecutivos incluidos en el estudio entre enero de 2007 y abril de 2010. Se investigo la incidencia de hemorragias mayores y trombosis del stent durante un periodo de 2 anos. La hemorragia mayor se evaluo mediante la puntuacion CRUSADE y los criterios del Bleeding Academic Research Consortium. Se estratifico a los pacientes en los siguientes grupos segun los criterios del ensayo SYNTAX: baja (= 22; n = 484), intermedia (23-32; n = 128) y alta (= 33; n = 110). Resultados Se observaron hemorragias mayores en 47 pacientes (6,5%) en el periodo de estudio de 2 anos, y hubo 12 episodios de trombosis del stent (1,7%). Las tasas de hemorragia mayor en los pacientes de los terciles bajo, intermedio y alto de la puntuacion SYNTAX fueron del 2,9, el 7,8 y el 20,9% respectivamente (p < 0,0001). La puntuacion SYNTAX mostro una hazard ratio ajustada de hemorragia mayor a los 2 anos de 1,81 (intervalo de confianza del 95%, 1,27-2,57). El valor predictivo del area bajo la curva de caracteristicas operativas del receptor ajustada por hemorragia mayor mejoro significativamente tras la inclusion de la puntuacion CRUSADE (estadistico C, 0,890 frente a 0,812). Conclusiones Aunque la puntuacion SYNTAX puede predecir el riesgo de hemorragias mayores, el valor predictivo de la puntuacion CRUSADE fue superior. Estas puntuaciones pueden resultar de utilidad en la toma de decisiones clinicas respecto a las estrategias de revascularizacion y la duracion optima del tratamiento antiagregante plaquetario doble tras implante de stents liberadores de farmacos.

Defibrillation threshold (DFT) testing during implantable cardioverter defibrillator (ICD) implantations is considered necessary for appropriate shock therapy and to measure the safety margin. However, the relationship between the DFT with modern era devices and the clinical outcome, including the total mortality is limited, which may lead to DFT testing itself being questioned. This study aimed to evaluate the relationship between the DFT and clinical outcome in ICD recipients.We enrolled 81 consecutive patients (66 males, aged 64.6 ± 13.8 years) who received an ICD implantation and underwent DFT testing. The DFT was measured with a step-by-step method in the patients upon implant. Further, we evaluated the relationship between the DFT and the clinical outcome, which included major cardiac adverse events and any cause of death.The mean DFT was 11.6 ± 9.24J in total. In 40 patients (49.4%), VF was terminated by a low output (5J), whereas 11 patients (13.6%) had a high DFT. The rates of atrial fibrillation were significantly higher in the high DFT group (63.6% versus 24.2%, P = 0.007). During the observational period (median 432 days; range from 151 days to 1146 days), the incidence of clinical events occurred in 22 patients (27.2%) in total. In a multivariate analysis, a high DFT was the only predictive factor for the incidence of the clinical outcome (OR 4.54, 95% CI 1.03-21.9, P = 0.045).

Background Pacemaker generators are routinely implanted in the anterior chest. However, where to place the generator may need to be considered from the mental, functional, and cosmetic standpoints. Methods In this study, we performed the left axillary pacemaker generator implantation with a direct puncture of the left axillary vein in 40 consecutive patients, and evaluated the late safety and efficacy of this implantation. Complications, changes in the lead sensing, pacing threshold, and impedance were used as safety indexes for a mean follow-up of 3.4 years. In addition, the efficacy was also evaluated by comparing their questionnaire survey results to 119 patients in a control group of anterior chest implantation. Results Lead dislodgements were observed in two patients of the experiment group. There were no migrations of generators from the implantation site or abnormal variations in the pacing threshold, lead sensing, or impedance. In the left anterior chest and left axillary groups, 85% and 10% of the patients were worried about an external impact, 80% and 25% were worried about electromagnetic interference, and 68% and 0% answered that the pacemaker implantation site was noticeable, respectively. Apparently, more patients had a sense of security and cosmetic satisfaction with the left axillary implantation. Conclusion The left axillary generator implantations may reduce the mental burden and cause no safety concerns, and may be performed if functional or cosmetic outcomes are required.

Causative arrhythmias of sudden cardiac arrest (SCA) are changing in this age of improved coronary care.The purpose of this study was to examine the frequency of terminal arrhythmias and the electrical events prior to SCA.We analyzed 24-hour Holter recordings of 132 patients enrolled from 41 institutions who either died (n = 88) or had an aborted death (n = 44). The Holter recordings were obtained for diagnosing and evaluating diseases and arrhythmias in those without any episodes suggestive of SCA.In 97 patients (73%), SCA was associated with ventricular tachyarrhythmias and in 35 (27%) with bradyarrhythmias. The bradyarrhythmia-related SCA patients were older than those with a tachyarrhythmia-related SCA (70 ± 13 years vs. 58 ± 19 years, P.001). The most common arrhythmia for a tachyarrhythmia-related SCA was ventricular tachycardia degenerating to ventricular fibrillation (45%). The bradyarrhythmia-related SCA was caused by asystole (74%) or AV block (26%). Spontaneous conversion was observed in 37 patients (38%) with ventricular tachyarrhythmias. Of those, 62% of the patients experienced symptoms including syncope, chest pain, or convulsion. Multivariate logistic analysis revealed that independent predictors of mortality for tachyarrhythmia-related SCAs were advanced age (odds ratio 1.04, 95% confidence interval 1.02-1.08) and ST elevation within the hour before SCA (odds ratio 3.54, 95% confidence interval 1.07-13.5). In contrast, the presence of preceding torsades de pointes was associated with spontaneous conversion (odds ratio 0.20, 95% confidence interval 0.05-0.66).The most frequent cause of SCA remains ventricular tachyarrhythmias. Advanced age and ST elevation before SCA are risk factors for mortality in tachyarrhythmia-related SCAs.

PurposePatients with normal stress myocardial perfusion imaging (MPI) results generally have an excellent prognosis with

AIM Reactive hyperemia peripheral arterial tonometry (RH-PAT) can be used to noninvasively assess the vascular function with respect to the digital microcirculation. Abnormalities are associated with coronary endothelial dysfunction. We therefore investigated whether impaired digital reactive hyperemia is associated with restenosis after percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS). METHODS This study included 86 patients with ACS who underwent successful primary PCI of native vessels for de novo lesions. The reactive hyperemia index (RHI) was calculated using RH-PAT at three weeks and eight months after ACS. The RHI was defined as the ratio of the digital pulse volume during reactive hyperemia to that observed at baseline. Restenosis was defined as diameter stenosis of ≥ 50% in the in-segment area based on the findings of quantitative coronary angiography performed at eight months. RESULTS Restenosis was detected in 17 patients (20%). There were no differences in the RHI at three weeks between the patients with and without restenosis (1.70 vs. 1.87; p=0.13); however, the RHI values at eight months were significantly attenuated in the patients with restenosis versus those without (1.75 vs. 2.12; p=0.03). A univariate logistic regression analysis showed that the eight-month RHI (＜2, obtained from a receiver operating characteristic analysis) was a significant risk factor for restenosis (odds ratio: 4.23, 95% confidence interval: 1.25 to 14.28, p=0.02). CONCLUSIONS Impairment of the digital hyperemic response at eight months is associated with restenosis after primary intervention in patients with ACS, suggesting the potential of RH-PAT as a noninvasive test for identifying patients with a high risk of restenosis.

A 76-year-old male who had already been diagnosed with ischemic heart disease and severe aortic stenosis was transferred to our hospital in a state of cardiogenic shock. We finally diagnosed him with severe aortic stenosis. We decided to perform emergency balloon aortic valvuloplasty (BAV) as a bridge treatment to surgical repair. We first performed BAV with a double balloon technique, and next with a triple balloon technique. As a result, the blood pressure recovered, and surgical aortic valve repair could thus be successfully performed.

The association of fibroblast growth factor 23 (FGF-23) with vascular disease in patients with preserved renal function is not well understood. The purpose of this study was to investigate the relationship of serum FGF-23 with coronary calcification in patients without chronic kidney disease and diabetes mellitus (DM).A cross-sectional study was performed in 148 consecutive patients with suspected coronary artery disease who underwent 64-slice computed tomography coronary angiography for diagnosis of coronary artery disease. Patients with eGFR60 mL/min/1.73 m(2), proteinuria, or DM were excluded. Associations of coronary calcification (evaluated by Agatston score) were examined with classical risk factors and with inflammatory markers, adipocytokines and FGF-23.The median creatinine, eGFR and FGF-23 levels were 0.7 mg/dL, 74.6 mL/min/1.73 m(2), and 26 pg/mL respectively. The strongest association was found between age and Agatston score (r = 0.367, p 0.001) in univariate logistic regression analysis. No atherogenic risk factors, including inflammatory markers and adipocytokine levels, were associated with Agatston score. Among calcium/phosphate metabolism markers, FGF-23 showed a weak but significant correlation with Agatston score (r = 0.169, p = 0.039). In multivariate linear regression analysis, age and FGF-23 (r = 0.188, p = 0.016) were independently associated with the Agatston score.Serum FGF-23 levels were associated with coronary calcification independently of classical risk factors and of adipocytokines and inflammatory markers in patients with preserved renal function. FGF-23 may also have a direct effect on progression of coronary calcification and further studies are required to examine this issue.

BACKGROUND To reduce myocardial damage caused by implantable cardioverter defibrillator (ICD) shock, the left axilla was studied as an alternative pulse generator implantation site, and compared with the traditional implantation site, the left anterior chest. METHODS AND RESULTS Computer simulation was used to study the defibrillation conduction pattern and estimate the simulated defibrillation threshold (DFT) and myocardial damage when pulse generators were placed in the left axilla and left anterior chest, respectively; pulse generators were also newly implanted in the left axilla (n=30) and anterior chest (n=40) to compare the corresponding DFT. On simulation, when ICD generators were implanted in the left axilla, compared with the left anterior chest, the whole heart may be defibrillated with a lower defibrillation energy (left axilla 6.4 J vs. left anterior chest 12.0 J) and thus the proportion of cardiac myocardial damage may be reduced (2.1 vs. 4.2%). Clinically, ventricular fibrillation was successfully terminated with a defibrillation output ≤5 J in 86.7% (26/30) of the left axillary group, and in 27.5% (11/40) of the left anterior group (P

Objectives The aim of this study was to characterize coronary plaque in target lesions with vessel remodeling using iMap-intravascular ultrasound (IVUS). Background The relationship between the plaque component and vessel remodeling remains to be elucidated. iMAP-IVUS is an imaging system that can be used to assess the plaque composition by radiofrequency signals from 40 MHz IVUS. Methods IVUS examinations were performed for the de novo target vessels of 146 stable angina pectoris patients (174 vessels). The patients were divided into two groups: including a nonpositive remodeling group (non-PR, remodeling index ≤ 1.0, 125 vessels) and a positive remodeling group (PR, remodeling index > 1.0, 49 vessels). Results The percent plaque burden in the PR group were lager than those in the non-PR group (79.05% vs. 74.36%, P < 0.01). Attenuation plaques were more frequently observed in PR group (40.8% vs. 12.1%, P < 0.0001). The percentages of lipidic and necrotic relative areas at the minimum lumen sites were greater in the PR group than in the non-PR group (7.22% vs. 6.03%, P

Summary Background Circadian variation has been accepted as a factor in acute myocardial infarction (AMI). An increased incidence of cardiac events in the morning has been reported for a long time. Recent reports have indicated that the onset of AMI shows two peaks, which occur in the morning and evening. It has also been demonstrated that circadian pattern of AMI may vary with sex and age. Methods and results We investigated 522 consecutive patients who underwent primary percutaneous coronary intervention (PCI) for ST segment elevation myocardial infarction (STEMI) between 2000 and 2010. The patients were classified into 3 age groups: younger (≤59 years old), intermediate (60–79 years old), and older (≥80 years old). Clinical data were investigated, including the age and sex, angiographic characteristics, and time of onset of STEMI. There were two peaks in the onset of STEMI throughout the day, which were at 7:00–10:00 and 19:00–21:00 h, among all patients (male and female). Stratified analysis showed that older females formed the main part of the second peak. Conclusions There were two peaks in the onset of STEMI in a Japanese population in Tokyo. The second peak was significantly dominated by the older female group. Age and gender influenced the second peak in the circadian variation of AMI in a Japanese population in Tokyo.

Previous epidemiological studies demonstrated plaque vulnerability to be high in diabetic patients. iMap-intravascular ultrasound (IVUS) is a recently developed radiofrequency 40 MHz IVUS imaging system for tissue characterization. This study aimed to characterize coronary plaque in target lesions of diabetic patients using iMap-IVUS.We studied 175 treated vessels in 146 patients with stable angina pectoris and analyzed plaque components of culprit lesions by iMAP-IVUS. Patients were divided into 2 groups: non-diabetic (non-DM: 112 vessels, 93 patients) and diabetic (DM: 63 vessels, 53 patients).In gray-scale IVUS 2D analysis, there were no differences in IVUS parameters. In 3D analysis, the DM group tended to have a larger plaque volume (p=0.07) and plaque burden (p=0.10). At minimum lumen sites, the absolute lipidic and necrotic areas (0.84 ± 0.44 mm(2) vs. 0.58 ± 0.41 mm(2), p0.001, and 2.42 ± 1.65 mm(2) vs. 1.46 ± 1.76 mm(2), p0.001, respectively) and percent lipidic and necrotic areas were significantly greater in the DM than in the non-DM group (8.39 ± 3.38% vs. 5.25 ± 2.30%, p0.0001, and 23.65 ± 11.54% vs. 12.99 ± 10.71%, p0.0001, respectively). In addition, the absolute lipidic and necrotic volumes (11.75 ± 10.59 mm(3) vs. 8.18 ± 6.24 mm(3), p0.01, and 29.99 ± 28.90 mm(3) vs. 19.44 ± 19.35 mm(3), p0.01, respectively) and percent lipidic and necrotic volumes were significantly greater in the DM than in the non-DM group (6.27 ± 1.92% vs. 5.13 ± 1.82%, p0.0001, and 16.54 ± 7.56% vs. 12.08 ± 6.05%, p0.0001, respectively).Characterization of coronary plaque by iMAP-IVUS in diabetic patients showed increased lipidic amount and necrotic plaque volume relative to subjects without DM.

Background: Cardiac resynchronization therapy (CRT) is effective in reducing morbidity and mortality in systolic heart failure patients with cardiac dyssynchrony as demonstrated in studies with primarily Western populations. Although CRT devices with a defibrillator (CRT-D) became available in Japan since 2006, their efficacy remains uncertain in Japanese patients. In this prospective, multicenter study, the efficacy of CRT-D therapy in an all-Japanese population was compared with the study conducted in the US, Multicenter InSync ICD Randomized Clinical Evaluation (MIRACLE-ICD). Methods and Results: Ninety-three patients were evaluated according to the subject selection criteria of the MIRACLE-ICD study, and 80 patients were enrolled. Results at baseline and 6-month post-CRT-D implantation were compared in terms of composite clinical response (CCR) and other secondary endpoints. Quality of life (QOL) was assessed with a validated Japanese version of the Minnesota Living with Heart Failure questionnaire. CCR was improved in 55 patients (68.8%), unchanged in 14 (17.5%), and worsened in 11 patients (13.7%) (MIRACLE-ICD general phase: 62.0%, 13.4% and 24.6%, respectively). Non-inferiority was verified by 1-sided test with 10% equivalence margin. QOL score improved significantly (50.0±26.2 vs. 23.6±20.2, P

Intravascular ultrasound studies have shown that patients with unstable angina pectoris (UAP) more frequently had soft plaques in the culprit coronary arteries than patients with stable angina pectoris (SAP). We evaluated coronary plaque characteristics of culprit lesions in patients with UAP by 64-slice computed tomographic coronary angiography (64-slice CTCA). 64-slice CTCA (Aquilion 64, Toshiba Medical Systems, Otawara, Japan) was performed in 30 patients (UAP = 14, SAP = 16) before percutaneous coronary intervention (PCI). Coronary plaque area was measured by manual tracing for the difference between the area within the external elastic membrane and the area of the vessel lumen at the site of maximal luminal narrowing as observed on a cross-sectional 64-slice CTCA image where PCI was performed. Within this plaque area, CT low-density plaque area (< 50 Hounsfield units) was automatically calculated. There were no differences in stenotic rate and whole plaque area of the culprit lesion between patients with UAP and SAP. However, the CT low-density plaque area was significantly greater in patients with UAP than in those with SAP. A greater area of CT low-density plaque in the culprit lesion is associated with UAP rather than SAP. Measuring CT-low density plaque area on 64-slice CTCA images could be useful for understanding the clinical setting of UAP.

Sixty-four-slice multidetector row computed tomography is a noninvasive method of assessing coronary artery stenosis and plaque composition. The aim of this study was to clarify the relation between plaque composition and coronary heart disease. Three hundred sixty consecutive patients and 1,085 plaques were evaluated using 64-slice multidetector row computed tomography. On axial or cross-sectional multiplanar reconstruction images, 3 regions of interest were randomly selected within each plaque. Soft plaques and calcified plaques were defined as having computed tomographic densities 130 Hounsfield units, respectively. The association between coronary risk factors and plaque composition was analyzed. The number of plaques and the mean computed tomographic density of plaques were significantly higher in men than in women (p = 0.002 and p = 0.04, respectively). Coronary plaques were more frequent in patients with stroke, diabetes, hypertension, and dyslipidemia than in patients without these conditions (all p values

Background Identification of coronary plaque composition is important for selecting the treatment strategy, and 64-slice computed tomography (CT) is a noninvasive method of characterizing atherosclerotic plaques. However, the correlation between plaque characteristics detected by CT and intravascular ultrasound (IVUS) is not clear. A 40 MHz IVUS imaging system (iMap-IVUS) has recently been developed to evaluate plaque composition. The aim of this study was to compare iMap-IVUS with 64-slice CT angiography for the characterization of non-calcified coronary plaques. Methods and results Both 64-slice CT angiography and iMap-IVUS were performed in 19 patients (38 plaques). CT values were measured as Hounsfield units (HU) in circular regions of interest (ROI) drawn on the plaques. The iMap-IVUS system analyzed coronary plaques as fibrotic, lipidic, necrotic, or calcified tissue based on the radiofrequency spectrum. A positive correlation was found between CT values and the percentage of fibrotic plaque ( r = 0.34, p = 0.036) or calcified plaque ( r = 0.40, p = 0.011). Conversely, a negative correlation was found between CT values and the percentage of lipidic plaque ( r = −0.41, p = 0.01), or necrotic plaque ( r = −0.41, p = 0.01). Conclusions Good correlations were observed between the characteristics of non-calcified plaque determined by iMap-IVUS and the CT values of plaque detected by 64-slice CT scanning.

Objectives: Cilostazol, a type III phosphodiesterase inhibitor, is an antiplatelet agent with vasodilating properties. Positive inotropic and chronotropic effects are frequently observed with cilostazol, but there are few reports on the influence of cilostazol on left ventricular function. The aim of this study was to assess this effect using tissue Doppler imaging (TDI) and two-dimensional speckle-tracking echocardiography (2D-STE). Methods: Thirty-five patients with normal left ventricular ejection fraction were enrolled in the study. Left ventricular cardiac function was assessed by TDI and 2D-STE before and after oral administration of cilostazol. Peak strain was defined using the peak radial strain (PRS), peak circumferential strain (PCS) and peak longitudinal strain (PLS). Time to peak strain was defined based on the times to PRS, PCS, and PLS, as T-PRS, T-PCS, and T-PLS, respectively. Results: After cilostazol administration, there were significant decreases in the left ventricular end-diastolic and end-systolic diameters (47.3 ± 5.2 vs. 43.3 ± 4.9 mm, P < 0.0001; 29.3 ± 6.4 vs. 26.0 ± 5.5 mm, P < 0.0001, respectively), and significant increases in the left ventricular ejection fraction (70.6 ± 9.5 vs. 72.7 ± 7.8%, P = 0.0381) and peak systolic annular velocity (7.9 ± 1.7 vs. 9.5 ± 3.1 cm/sec, P < 0.0001). PRS, PCS, and PLS all increased significantly and T-PRS, T-PCS, and T-PLS all decreased significantly after cilostazol administration. Conclusion: Positive inotropic and chronotropic effects of cilostazol were found based on assessment by TDI and 2D-STE. We suggest that periodic echocardiographic assessment should be performed before and after oral administration of cilostazol. (Echocardiography 2011;28:431-437)

Background: Radiofrequency catheter ablation (RF) has recently become widely available for the treatment of atrial fibrillation (AF) and has broadened treatment options while confusing the selection of medication therapy or RF. Methods and Results: Two drugs for the maintenance of sinus rhythm (Ry) and 2 drugs for control of the pulse rate (Ra) were selected and the costs of medication therapy were calculated. RF procedures were grouped into 2 groups each for persistent or paroxysmal AF (RF) and for chronic AF (RFChr), according to the cost of the devices used. The calculated cost of medication therapy was 5,270-23,560 yen per month. The calculated cost of RF procedures was 1,063,200-2,029,640 yen. The costs of RF corresponded to those of Ry for 3.8-14.3 years. The costs of RFChr corresponded to those of Ra for 16.6-63.9 years. The treatment of complications ranged from 360,000 to 1,241,500 yen. Conclusions: From the aspect of medical costs and complications, RF should be considered for the treatment of patients with AF detected early or early-stage AF, whereas treatment for its complications should be given priority in patients with chronic AF associated with reduced cardiac function. (Circ J 2011; 75: 1860-1866)

Atrial fibrillation (AF) is the most common cardiac rhythm disorder and a major risk factor for stroke. For more than 60 years, warfarin has been the only approved anticoagulant for prevention of stroke in patients with AF. Although highly effective, it has many limitations that make its use difficult. Therefore, several novel anticoagulants are under development to overcome the limitations of warfarin, and some of these have entered phase III clinical trials. Dabigatran is an oral, reversible direct thrombin inhibitor approved in Europe and in several other countries for the prevention of venous thromboembolism after elective knee and hip replacement surgery. It has also been approved in the United States and Japan for the prevention of stroke and systemic embolism in patients with nonvalvular AF. In this review, the mechanism of action and pharmacological properties of new anticoagulants are described in detail, and the correct use of dabigatran in clinical practice is discussed.

The prognostic and diagnostic values of N-terminal pro-brain natriuretic peptide (NT-pro-BNP) in ischemic heart disease have already been investigated in many previous studies. Although NT-pro-BNP is affected by many factors, these previous studies did not strictly exclude them. This study included 110 patients who received coronary arteriography between November 2007 and September 2009. Excluded from the study were those patients who had clinical symptoms of heart failure, asynergy by echocardiography or left ventriculography (LVG), atrial fibrillation, prior myocardial infarction, valvular disease, lung disease, anemia or renal dysfunction. We compared the laboratory data, LVG and early transmitral-to-early diastolic annular velocity ratio (E/E (a)) in echocardiography between the group with coronary stenosis and the group without it. NT-pro-BNP and the low-density lipoprotein/high-density lipoprotein ratio (LDL/HDL) independently associated with the presence of coronary artery stenosis (odds ratio of NT-pro-BNP, each 50 pg/ml 2.367, 95% confidence interval 1.302-4.303, p = 0.005). The area under the curve of the receiver-operating characteristic (ROC) curve of NT-pro-BNP, used to predict coronary artery stenosis, was 0.801 (0.719-0.883, p 0.001). According to the ROC curve, the optimal cut-off level for predicting coronary stenosis was 64.3 pg/ml (sensitivity 82.5%, false-positive 34%). NT-pro-BNP is an attractive supplemental marker to predict the presence of coronary artery stenosis in a population that strictly excluded any affecting factors. In the population without factors affecting NT-pro-BNP, a slight increase suggests the presence of ischemic heart disease. The normal criteria for NT-pro-BNP in the patients undergoing coronary angiography may be much lower than the one currently used.

Summary Background The best way to treat in-stent restenosis (ISR) after drug-eluting stent (DES) implantation remains unclear. The aim of this study was to evaluate angiographic restenosis and target lesion revascularization (TLR) at 8 months after intervention in patients with DES-ISR, and to identify predictive factors of subsequent TLR after treatment of DES-ISR. Methods and results A total of 100 patients with 105 lesions underwent subsequent intervention for DES-ISR between April 2004 and January 2009. At baseline, focal and diffuse ISR were observed in 76.2% and 23.8%. DES-ISR was treated by five modalities: sirolimus-eluting stent (n = 42); paclitaxel-eluting stent (n = 24); balloon angioplasty (n = 23); cutting balloon angioplasty (n = 14); and bare-metal stent (n = 2). Angiographic follow-up data were available for 95 lesions (91%). The rates of angiographic restenosis and TLR were 37.9% and 33.3%. Late loss of sirolimus-eluting stent, paclitaxel-eluting stent, cutting balloon, and balloon angioplasty were 0.50 mm, 0.49 mm, 0.93 mm, and 1.10 mm. By multivariate analysis, totally occluded ISR (OR 15.43, p = 0.0005), diabetes mellitus (OR 3.45, p = 0.02), and re-stenting with DES (OR 0.14, p = 0.0002) were identified as independent predictors of TLR. Conclusions The restenosis rate was significant in this cohort of patients with DES-ISR. Angiographic pattern of DES-ISR and diabetes mellitus are the most important predictors of TLR, whereas re-stenting with DES is protective.

SummaryBackgroundThe disadvantageous effect of kidney dysfunction on left ventricular (LV) diastolic function is still unknown.MethodsForty non-chronic kidney disease (CKD) patients and 202 CKD patients, aged 40–89, were examined by standard echocardiography and the new modality of tissue Doppler imaging. All subjects were divided into 5 groups depending on their estimated glomerular filtration rate (GFR: ml/min/BSA). Classifications by GFR were defined as follows: group 1 (more than 90: normal subjects), group 2 (60–89), group 3 (30–59), group 4 (15–29) and group 5 (less than 15).ResultsThere were no significant differences in LV systolic function among the groups. Mitral E velocity was significantly lower in groups 1–4 (p

Background— The prognosis of patients with saddleback or noncoved type (non–type 1) ST-elevation in Brugada syndrome is unknown. The purpose of this study was to clarify the long-term prognosis of probands with non–type 1 ECG and those with coved (type 1) Brugada-pattern ECG. Methods and Results— A total of 330 (123 symptomatic, 207 asymptomatic) probands with a coved or saddleback ST-elevation ≥1 mm in leads V 1 –V 3 were divided into 2 ECG groups—type 1 (245 probands) and non–type 1 (85 probands)—and were prospectively followed for 48.7�15.0 months. The absence of type 1 ECG was confirmed by drug provocation test and multiple recordings. The ratio of individuals with a family history of sudden cardiac death (14%) was lower than previous studies. Clinical profiles and outcomes were not notably different between the 2 groups (annual arrhythmic event rate of probands with ventricular fibrillation; type 1: 10.2%, non–type 1: 10.6%, probands with syncope; type 1: 0.6%, non–type 1: 1.2%, and asymptomatic probands; type 1: 0.5%, non–type 1: 0%). Family history of sudden cardiac death at age P =0.005; hazard ratio, 2.66; 95% confidence interval, 1.06 to 6.71; P =0.03, respectively, by multivariate analysis), although spontaneous type 1 ECG and ventricular fibrillation inducibility by electrophysiological study were not reliable parameters. Conclusions— The long-term prognosis of probands in non–type 1 group was similar to that of type 1 group. Family history of sudden cardiac death and the presence of early repolarization were predictors of poor outcome in this study, which included only probands with Brugada-pattern ST-elevation.

Background: While preprocedural statin treatment for acute coronary syndrome (ACS) is widely regarded as beneficial, there has been no prospective randomized multicenter trial of patients with non-ST elevation ACS in the Japanese population to examine the efficacy of preprocedural aggressive statin use. The aim of this study was to confirm this effect by prospective randomized multicenter design. Methods: Fifty patients who presented with non-ST elevation ACS were enrolled, and randomly assigned to aggressive statin administration before percutaneous coronary intervention (PCI). Troponin-T (TnT), creatine phosphokinase (CK), CK-myocardial band (CK-MB), high-sense C-reactive protein (hs-CRP), and brain natriuretic peptide (BNP) were measured at baseline and/ or after procedure. Results: Three days after PCI, the statin group had significantly less CK elevation compared with the nonstatin group (84±17 IU/l versus 180±68 IU/l, respectively, p = 0.02). CK-MB elevation also tended to be lower in the statin group than in the nonstatin group (3.2±1.9 versus. 7.0±3.0, respectively, p = 0.07), as was BNP level (3.2±1.9 versus 7.0±3.0 pg/ml, respectively, p = 0.07). The change of serum LDL cholesterol was significantly correlated with CK ( p = 0.01) and TnT ( p = 0.02) at 1 day after PCI. Conclusions: Aggressive statin usage before PCI to Japanese patients with non-ST elevation ACS appears to reduce myocardial damage after procedure. The degree of serum lipid level reduction may reflect the vulnerability of atheromatous plaques that could cause cardiac damage after PCI.

Introduction: This is a rare case of antidromic reciprocating tachycardia developing 8 years after successful catheter ablation. Result: A 15-year-old girl had recurrence of palpitations 8 years after the ablation of manifest right posteroseptal accessory pathway. Atrial burst pacing revealed Wenckebach atrioventricular conduction with preexcitation. Wide QRS tachycardia with identical morphology to sinus rhythm associated with retrograde His potential recorded immediately after the V-wave was induced by isoproterenol infusion. Atrial premature stimulus applied at the identical timing of His potential advanced the subsequent ventricular beat and His potential. Conclusion: Catheter ablation may produce decremental accessory pathway conduction and rarely cause antidromic atrioventricular reciprocating tachycardia. This may be explained by a presence of “de novo” accessory pathway with decremental conduction properties that became manifest after the first ablation.

Objectives To investigate stent deformation by torsional stress after implantation at the ostium of a model coronary artery. Background Little is known about coronary stent deformation, especially the association between stent design and deformation at the coronary ostium. Recent reports have suggested that mechanical factors are important for stent restenosis. Methods A coronary ostium model was constructed and three different stents (Express 2 , Cypher, and Tsunami, n =5 each) were implanted at the aorto-ostial junction. Differences of stent deformation were assessed after exposure to torsional stress. Intravascular ultrasound was used to measure the luminal area along each stent. Then the extent and pattern of plastic deformation were compared between the three stent types. Results The Express 2 stents and Cypher stents both showed significant deformation ( P P =.045, respectively) adjacent to the ostium, whereas only a minimal decrease of luminal area was observed with the Tsunami stent. In the central and distal parts of each stent, the decrease of luminal area was minimal and no differences were noted among the three types. Sudden fracture of a Cypher stent strut occurred during the experiment. Conclusion Differences of structural characteristics influence permanent plastic deformation at sites where continuous stress occurs, such as the coronary ostium. A more elastic design may show better resistance to such stress.

Background Although previous clinical trials demonstrated the non-inferiority of a rate control to rhythm control strategy for management of atrial fibrillation (AF), the optimal treatment strategy for paroxysmal AF (PAF) remains unclear. Methods and Results A randomized, multicenter comparison of rate control vs rhythm control in Japanese patients with PAF (the Japanese Rhythm Management Trial for Atrial Fibrillation (J-RHYTHM) study) was conducted. The primary endpoint was a composite of total mortality, symptomatic cerebral infarction, systemic embolism, major bleeding, hospitalization for heart failure, or physical/psychological disability requiring alteration of treatment strategy. In the study, 823 patients with PAF were followed for a mean period of 578 days. The primary endpoint occurred in 64 patients (15.3%) assigned to rhythm control and in 89 patients (22.0%) to rate control (P=0.0128). No significant differences between the treatment strategies were observed in the incidences of death, stroke, bleeding and heart failure. Meanwhile, significantly fewer patients requested changes of assigned treatment strategy in the rhythm control vs the rate control group, which was accompanied by improvement in AF-specific quality of life scores. Conclusion The J-RHYTHM study showed that rhythm control was associated with fewer primary endpoints than rate control. However, mortality and cardiovascular morbidity were not affected by the treatment strategy (umin-CTR No. C000000106).

Background Subcutaneous implantable cardiac defibrillator (S-ICD) systems have a lower invasiveness than traditional ICD systems, and expand the indications of ICD implantations. The S-ICD standard defibrillation shock output energy, however, is approximately 4 times that of the traditional ICD system. This raises concern about the efficacy of the defibrillation and myocardial injury. In this study, we investigated the defibrillation efficacy and myocardial injury with S-ICD systems based on computer simulations. Methods and results First, computer simulations were performed based on the S-ICD system configurations proposed in a previous study. Furthermore, simulations were performed by placing the lead at the left or right parasternal margin and the pulse generator in the superior and inferior positions (0-10 cm) of the recommended site. The simulated defibrillation threshold (DFT) for the 4 S-ICD system configurations were 30.1, 41.6, 40.6, and 32.8 J, which were generally similar to the corresponding clinical results of 33.5, 40.4, 40.1, and 34.3 J. Conclusions The simulated DFT were generally similar to their clinical counterparts. In the simulation, the S-ICD system had a higher DFT but relatively less severe myocardial injury compared with the traditional ICD system. Further, the lead at the right parasternal margin may correspond to a lower DFT and cause less myocardial injury.

Background More efficacious and/or safer decongestive therapy is clearly needed in acute heart failure (AHF) patients complicated by renal dysfunction. We tested the hypothesis that adding tolvaptan, an oral vasopressin-2 receptor antagonist, to conventional therapy with loop diuretics would be more effective treatment in this population. Methods and Results A multicenter, open-label, randomized control trial was performed, and 217 AHF patients with renal dysfunction (estimated glomerular filtration rate 15–60 mL • min −1 • 1.73 m −2 ) were randomized 1:1 to treatment with tolvaptan (n = 108) or conventional treatment (n = 109). The primary end point was 48-hour urine volume. The tolvaptan group showed more diuresis than the conventional treatment group (6464.4 vs 4999.2 mL; P .001) despite significantly lower amounts of loop diuretic use (80 mg vs 120 mg; P .001). Dyspnea relief was achieved significantly more frequently in the tolvaptan group at all time points within 48 hours except 6 hours after enrollment. The rate of worsening of renal function (≥0.3 mg/dL increase from baseline) was similar between the tolvaptan and conventional treatment groups (24.1% vs 27.8%, respectively; P = .642). Conclusions Adding tolvaptan to conventional treatment achieved more diuresis and relieved dyspnea symptoms in AHF patients with renal dysfunction. Clinical Trial Registration URL: http://www.umin.ac.jp/ctr/index/htm/ Unique identifier: UMIN000007109