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Background: Treatment options for high-risk Brugada syndrome (BrS) with recurrent ventricular fibrillation (VF) are limited. Catheter ablation is increasingly performed but a large study with long-term outcome data is lacking. We report the results of the multicenter, international BRAVO (Brugada Ablation of VF Substrate Ongoing Registry) for treatment of high-risk symptomatic BrS. Methods: We enrolled 159 patients (median age 42 years; 156 male) with BrS and spontaneous VF in BRAVO; 43 (27%) of them had BrS and early repolarization pattern. All but 5 had an implantable cardioverter-defibrillator for cardiac arrest (n=125) or syncope (n=34). A total of 140 (88%) had experienced numerous implantable cardioverter-defibrillator shocks for spontaneous VF before ablation. All patients underwent a percutaneous epicardial substrate ablation with electroanatomical mapping except for 8 who underwent open-thoracotomy ablation. Results: In all patients, VF/BrS substrates were recorded in the epicardial surface of the right ventricular outflow tract; 45 (29%) patients also had an arrhythmic substrate in the inferior right ventricular epicardium and 3 in the posterior left ventricular epicardium. After a single ablation procedure, 128 of 159 (81%) patients remained free of VF recurrence; this number increased to 153 (96%) after a repeated procedure (mean 1.2±0.5 procedures; median=1), with a mean follow-up period of 48±29 months from the last ablation. VF burden and frequency of shocks decreased significantly from 1.1±2.1 per month before ablation to 0.003±0.14 per month after the last ablation ( P P =0.0274). There were no arrhythmic or cardiac deaths. Complications included hemopericardium in 4 (2.5%) patients. Conclusions: Ablation treatment is safe and highly effective in preventing VF recurrence in high-risk BrS. Prospective studies are needed to determine whether it can be an alternative treatment to implantable cardioverter-defibrillator implantation for selected patients with BrS. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04420078.

Background The subcutaneous implantable cardioverter defibrillator (S-ICD) is an alternative to the transvenous implantable cardioverter defibrillator for the prevention of sudden cardiac death. Here, we report a rare case of refractoriness to an S-ICD after frequent therapies for ventricular fibrillation (VF) storms. Case presentation A 24-year-old man underwent a bout of syncope with vomiting and incontinence at home. He was brought to the emergency room and was witnessed to spontaneously go into VF successfully converted by external defibrillation. Previously, he was diagnosed with a type I Brugada electrocardiogram pattern by a pilsicainide administration test in another hospital. Although he had a family history of sudden cardiac death in 3 relatives, including his brother, he was followed closely without any therapies because he had never had an episode of syncope. He was implanted with an S-ICD without any trouble. Seven months later, frequent S-ICD shocks for VF storms occurred. His VF was controlled by using intravenous amiodarone, which was converted to an oral preparation. However, his VF recurred after another 2 months. The analysis of his S-ICD data revealed that 4 consecutive shock deliveries could not terminate his VF and the final shock delivered could fortunately terminate it because of a high defibrillation threshold test (DFT) due to an increasing shock impedance (64 to 90 Ω). First, we performed an epicardial Brugada syndrome ablation and subsequently replaced and repositioned the S-ICD lead from a left to a right parasternal site. After the re-implantation of the S-ICD, the DFT test improved to within normal range. According to the pathological analysis, infiltration of inflammatory cells and extensive fibrosis were confirmed in the subcutaneous tissue around the shock lead and S-ICD body. Conclusion Frequent S-ICD shocks for VF storms might cause various pathological changes around the device and lead to a high DFT.

Background: Coronary artery spasms (CASs), which can cause angina attacks and sudden death, have been recently reported during catheter ablation. The aim of the present study was to report the incidence, characteristics, and prognosis of CASs related to atrial fibrillation (AF) ablation procedures. Methods and Results: The AF ablation records of 22,232 patients treated in 15 Japanese hospitals were reviewed. CASs associated with AF ablation occurred in 42 of 22,232 patients (0.19%). CASs occurred during ablation energy applications in 21 patients (50%). CASs also occurred before ablation in 9 patients (21%) and after ablation in 12 patients (29%). The initial change in the electrocardiogram was ST-segment elevation in the inferior leads in 33 patients (79%). Emergency coronary angiography revealed coronary artery stenosis and occlusions, which were relieved by nitrate administration. No air bubbles were observed. A comparison of the incidence of CASs during pulmonary vein isolation between the different ablation energy sources revealed a significantly higher incidence with cryoballoon ablation (11/3,288; 0.34%) than with radiofrequency catheter, hot balloon, or laser balloon ablation (8/18,596 [0.04%], 0/237 [0%], and 0/111 [0%], respectively; P

Introduction: Although modulation of atrial fibrillation (AF) drivers and/or substrates has been proposed as one of the effective ablation strategies for non-paroxysmal AF (Non-PAF), previous meta-analyses showed that ablation, targeting complex fractionated atrial electrogram (CFAE) indirectly-reflecting Non-PAF drivers, had no additional benefit for post-pulmonary vein isolation (PVI) Non-PAF. As an alternative ablation strategy for Non-PAF, rotor ablation has been proposed as one of the potentiated ablation strategies for Non-PAF. However, the optimal ablation strategy is still unclear because reliable method detecting AF drivers remain unsettled in clinical practice. Hypothesis: Because rotors are known as key mechanisms for Non-PAF, we might open the possibility of Non-PAF control by the real-time visualization of wave dynamics during AF ablation. Methods: Consecutive 140 Non-PAF patients were enrolled in this study. The clinically-available online and real-time AF imaging system with high-spatiotemporal density (ExTRa Mapping TM ) developed by our group was applied in case Non-PAF was remained after PVI. Then, we detected and ablated non-passively-activated areas where rotational activations in the form of meandering rotors and/or multiple wavelets assumed to contain Non-PAF drivers were frequently observed (figure, top). The recurrence rate of Non-PAF or atrial tachycardia (AT) after the ablation was compared to that in patients underwent PVI-alone at our hospital. Results: The propensity scores selected each 34 people from ExTRa-strategy group and PVI-alone group (figure, middle). The 24-month freedom ratio from Non-PAF/AT in the matched-ExTRa-strategy group was higher than the matched-PVI-alone group, which was close to significance (p = 0.056) (figure, bottom). Conclusion: The ExTRa Mapping-guided ablation for PVI-refractory Non-PAF might be superior to PVI-alone.

A 51‐year‐old male with dextrocardia and situs inversus underwent catheter ablation for paroxysmal atrial fibrillation. Because the procedure through the trans‐septal approach was impossible due to the inferior vena cava continuity with azygos vein, we performed pulmonary vein isolation using magnetic navigation system through the retrograde trans‐aortic approach. Superior and inferior left‐sided and superior right‐sided pulmonary veins could be isolated which was confirmed by the ablation catheter. The patient was free from atrial fibrillation episode at the 12 months follow‐up except only one palpitation episode lasting nearly 12 hours at 9 months after the ablation.

Catheter ablation is a common treatment for ar- rhythmia and the number of procedures is increasing. Takatsuki General Hospital introduced a remote mag- netic navigation system into clinical practice for the first time in Japan. This system produces- magnetic flux density of 0.08-0.1 Tesla. Catheter ablation is usu- ally performed under deep sedation at our facility ; however, general anesthesia is needed in some cases. Although many cases of general anesthesia for MRI have been reported, there has been no report of gen- eral anesthesia under the unique environment of a weak magnetic field. We use MRI-certified equipment such as an anesthesia machine and a patient monitor in the heart rhythm center. There is no contraindication for the selection of anesthetic agents. Analgesia, depending on pain or burning sensation by ablation, and immobilization are required. Anesthesiologists must be aware that there are some differences in gen- eral anesthesia in the MRI room compared with the heart rhythm center, including the environmental set- ting, limitations in the use of certain medical equipment and procedure-related knowledge.

Background: We assessed high-frequency stimulation (HFS)-induced changes in the atrial fibrillation (AF) cycle length (AFCL) in the pulmonary vein (PV) after ganglionated plexi (GP) ablation. Methods: Twenty-two patients undergoing catheter ablation for AF were retrospectively enrolled. Sites showing a vagal response (VR) to HFS were defined as GP-positive sites. AFCL was determined in the adjacent PV, distant PV, coronary sinus, and right atrium. Twenty cycles were counted before and after each HFS. After radiofrequency application to the GP site, HFS was repeated. Results: At GP-positive sites (n=57), significant shortening of the AFCL was detected in the adjacent PV (17% shortening, 165±38 to 137±27 ms, p

Background The predictive value of T-wave alternans (TWA) for lethal ventricular tachyarrhythmia in patients with left ventricular (LV) dysfunction is controversial. Also, long-term arrhythmia risk of patients ineligible for the TWA test is unknown. Methods This was a multicenter, prospective observational study of patients with LV ejection fraction ≤40% due to ischemic or non-ischemic cardiomyopathies, designed to evaluate the prognostic value of TWA for lethal ventricular tachyarrhythmia. The primary end point was a composite of sudden cardiac death, sustained rapid ventricular tachycardia (VT) or ventricular fibrillation (VF), and appropriate defibrillator therapy for rapid VT or VF. Results Among 453 patients enrolled in the study, 280 (62%) were eligible for the TWA test. TWA was negative in 82 patients (29%), who accounted for 18% of the total population. The median of follow-up was 36 months. The 3-year event-free rate for the primary end point was significantly higher in TWA-negative patients (97.0%) than in TWA non-negative patients (89.5%, P = 0.037) and those ineligible for the TWA test (84.4%, P = 0.003). Multivariable analysis identified both non-negative TWA [hazard ratio (HR) 4.43; 95% confidence interval (CI) 1.02–19.2; P = 0.047) and ineligibility for the TWA test (HR 6.89; 95% CI 1.59–29.9; P = 0.010) to be independent predictors of the primary end point. Conclusions TWA showed high negative predictive ability for lethal ventricular tachyarrhythmia in patients with LV dysfunction, although the TWA-negative patients accounted for only 18% of the entire population. Those ineligible for the TWA test had the highest risk for lethal ventricular tachyarrhythmia. Electronic supplementary material The online version of this article (doi:10.1007/s00392-011-0368-2) contains supplementary material, which is available to authorized users.

The anatomical relationship between left ventricular pacing site and the anterior papillary muscle (A-PM) may have a major influence on the improvement of mitral regurgitation (MR) in cardiac resynchronization therapy (CRT). The aims of the present study were to assess the anatomical relationship between coronary veins and papillary muscles in patients with and without heart failure (HF), and to examine its contribution to the response to CRT. Sixty-one patients (36 patients with HF, 25 patients without HF) who underwent multi-detector computed tomography were studied. We measured the angle between the anterior papillary muscle and coronary veins (Ang. 1) and the angle between the anterior edge of the left ventricular free wall and A-PM (Ang. 2). Angle 1 of the posterolateral vein in the patients with HF was significantly smaller than those without HF (54.9 ± 11.1, 68.7 ± 15.8 degrees, respectively, P = 0.02). Supportively, Angle 2 of patients with HF was larger than that of patients without HF (100 ± 13.0, 87.3 ± 10.7 degrees, respectively, P 100 degrees), but not in patients with Ang. 2 < 100 degrees. A-PM tends to be located in a more posterior wall in patients with HF. Displacement of A-PM may have a potential role as a predictor of the response to CRT.

ポリエチレン製多孔性シート (平均孔径1.3μm, 空孔率75%, シートの厚さ2mm) に, 放射線グラフト重合法を適用して, エポキシ基をもつグラフト鎖を付与し, その後, グラフト鎖にキレート形成基であるイミノジ酢酸基を導入した。得られたキレート多孔性シートを直径13mmのディスク状に裁断し, 6cm3の空カートリッジに充填してキレートカートリッジを作製した。このカートリッジに硫酸ニッケル水溶液を透過させ, キレート多孔性ディスクにニッケルイオンを吸着させて, ニッケルイオン固定カートリッジを作製した。ニッケルイオン固定カートリッジを用いて, 大腸菌破砕液中のHis-tag融合タンパク質を精製できることを実証した。

A chelating porous sheet for use in solid-phase extraction was prepared by radiation-induced graft polymerization and subsequent chemical modifications. An epoxy-group-containing vinyl monomer was graft-polymerized onto a porous sheet made of polyethylene. The produced epoxy group of the graft chain was converted into an iminodiacetate group. The chelating porous sheet with a density of the iminodiacetate group of 2.1 mol/kg was cut into disks 13 mm in diameter to fit an empty cylindrical cartridge with a capacity of 6 mL. Breakthrough curves using the chelating-porous-disk-packed cartridge overlapped irrespective of the flow rate of the solution ranging up to 1500 mL/h because of negligible diffusional mass-transfer resistance of the copper ions to the iminodiacetate group of the graft chain.

BACKGROUND The ability to evaluate coronary stenosis using multi-detector computed tomography (MDCT) has been well discussed. In contrast, several studies demonstrated that the plaque burden measured by intravascular ultrasound (IVUS) has a relationship to the risk of cardiovascular events. the accuracy of MDCT was studied to determine plaque and vessel size compared with IVUS. METHODS AND RESULTS Fifty-six proximal lesions (American College of Cardiology/American Heart Association classification: segment 1, 5, 6) from 33 patients were assessed using MDCT and IVUS. The plaque and vessel area were measured from the cross-sectional image using both MDCT and IVUS. Eight coronary artery lesions with motion artifacts and heavily calcified plaques were excluded from the analysis. The vessel and lumen size evaluated using MDCT were closely correlated with those evaluated by IVUS (R(2)=0.614, 0.750 respectively). Furthermore, there was a strong correlation between percentage plaque area assessed by MDCT and IVUS (R(2)=0.824). CONCLUSION MDCT can noninvasively quantify coronary atherosclerotic plaque with good correlation compared with IVUS in patients with atherosclerosis.

We studied low frequency vibrational modes in a light-harvesting (LH) antenna component molecule (1, 3, 5-tri-phenylbenzene: tri-ph) of a LH dendrimer by measuring a coherent phonon (CP) signal and molecular vibration analyses with semi-empirical molecular orbital calculations. In a Fourier transform spectrum obtained from the transient CP signal, we found three vibrating components with the frequencies of 35 ± 13, 60 ± 10, and 84 ± 14 cm−1. In the lower frequency range than 100 cm−1, the molecular vibration analyses give the following three kinds of vibrational modes: torsional vibrations, a butterfly vibration and bending vibrations, in which peripheral aromatic rings librate against the central ring in different manners. We identified the lowest frequency vibrating component (35 ± 13 cm−1) as the torsional vibrational mode changing dihedral angles and co-planarities between the central and the peripheral aromatic rings. In addition, it was also found that the vibrational frequencies obtained by our measurements are higher than those of the vibrational mode analyses. These hardenings are considered to account for steric hindrance between the neighbor molecules after the crystallization.

The present study aimed at optimizing the scan protocol for multidetector-row computed tomography (MDCT) to adequately visualize coronary veins. Circulation time (Cir.T) was defined as the time period from the injection of contrast media into the coronary artery to the pervasion of the contrast media into the coronary sinus as observed by coronary angiography. We investigated the relation between the Cir.T and echocardiographic parameters in 64 patients. The left ventricular end-diastolic diameter (LVDd) and left ventricular end-systolic diameter (LVDs) were correlated with the Cir.T (r = 0.58, P0.0001, and r = 0.60, P0.0001 respectively). In addition, the left ventricular ejection fraction (LVEF) was negatively correlated with the Cir.T (r = 0.48, P0.0001). The average Cir. T was longer in patients with LVEF35% (8.0 s vs 6.7 s; P0.05) or LVDd55 mm (7.9 s vs 6.2 s; P0.05) than in the other patients. The quality of the MDCT images of the coronary veins obtained at different scan timings (coronary artery phase and 10 s or 15 s after the coronary artery phase) were graded and classified into four categories (0 = worst, 3 = best) in 25 patients with LVEF35%. The delays of 10 and 15 s after the coronary artery phase significantly improved the mean image quality (P0.05). The Cir.T was prolonged in patients with low LVEF and LV dilation. An appropriate delay improved the quality of the MDCT images of the coronary veins in patients with LV dysfunction.

Background : Cardiac resynchronization therapy (CRT) can improve heart failure symptoms and decrease mitral regurgitation (MR). Improved coordinated timing of mechanical activation of papillary muscle was reported to be a contributor to reduction of MR after CRT. Purpose : We tested the hypothesis that the anatomical location of anterior papillary muscle (A-PM) affects improvement of MR and other parameters after CRT. Methods : Twenty-three patients (age 69.8 ± 8.2 years, left ventricular ejection fraction (LVEF) 29.4 ± 6.9%, 16 male, 20 non-ischemic dilated cardiomyopathy, 3 previous myocardial infarcion) underwent both CRT and multi-detector computed tomography (MDCT) were studied. We measured the angle between the anterior edge of the left ventricular free wall and A-PM (Ang. PM) in cross sectional images of left ventricle obtained by MDCT. Patients were divided into 2 groups; 13 patients with severe A-PM displacement (Ang.PM >100 degree) and 10 patients with Ang.PM Results : Mean Ang.PM was 106 ± 12.2 degree. LVEF and NYHA functional class were significantly improved after 6 months of CRT in both groups (p < 0.05, respectively). However, significant decreases of the proportion of grade 2– 4 MR, left ventricular end-systolic and end-diastolic dimensions, and brain natriuretic peptide level after 6 months of CRT were observed only in patients with severe A-PM dislocation (p = 0.02, p = 0.04, p = 0.03 respectively). Conclusion : Posterior shift of A-PM may have a potential to predict improvement after CRT.

Mitral isthmus (MI) ablation is challenging. Blood flow in the CS and circumflex artery (LCx) may act as a heat sink and reduce the efficacy of radiofrequency ablation. Ablation in the CS also has the risk of injury to the LCx. We have reported to be able to visualize the precise anatomical characteristics between CS and LCx on MI obtained by MDCT. The aim of this study was to evaluate usefulness of MDCT guided MI ablation. Methods: Twenty patients (14 males, 61±11 y) whose CS and LCx images could be obtained simultaneously by MDCT were included in this study. We performed MI ablation between LIPV and the mitral annulus. The strategy for MDCT guided MI ablation were 1. MI line was designed just below LAA, 2. In case of LCx below CS, MI line was designed proximal the crossing point of LCX and CS, and 3. If LCX is presence on MI, MI line designed more laterally on comparatively peripheral LCX. Irrigated-tip catheters were used during MI ablation with the following settings: endocardial surface (maximum power: 40 W); CS (maximum power: 20 W). Results: The MI was blocked in 94.5% (19/20) of patients with 594±293 seconds of radiofrequency application. The epicardial ablation inside the CS was required in 45% (9/20) patients. No complications occurred. Conclusion: The MDCT guided MI ablation resulted in a high success rate of MI block without complications.

AF termination was often occurred during ganglionated plexi (GP) ablation. The purpose of this study was to characterize the electrograms at the site of AF termination by GP ablation. Method: Eighteen patients with AF termination by GP ablation were studied. In case of patients with sinus rhythm, AF was induced by rapid atrial pacing. The sites where vagal response was evoked by high-frequency stimulation were determined as GP sites and ablated. The bipolar electrograms were recorded in a 4.5-s window before the RF delivery. Result: AF termination was seen at superior left GP ablation in 3 patients, anterior right in 2 patients, inferior left in 6 patients, and inferior right (in 7 patients). Continuous electrical activity (CEA) was seen at the termination site in 16 (89%) patients. Other 2 patients without CEA, cycle length was 207±18 ms. The maximum duration of CEA was 1.8±0.3 of 4.5 sec. There were 2 patients with only CEA at the termination sites during all recording period. The maximum amplitude of CEA in 16 patients was 0.58±0.99 mV. Conclusion: The electrograms at the sites of AF termination by GP ablation show mainly transient CEA with relatively low voltage.

The Ganglionated Plexi (GP) and complex fractionated atrial electrograms (CFAE) play the important role as the perpetuator of atrial fibrillation (AF). GP ablation is known as alternative procedure for AF. The aim of this study was to evaluate the contrast between the area of the GP and CFAE. Method: Ten consecutive patients with AF were studied. For patients with sinus rhythm, AF was induced by rapid atrial pacing. The geometry of Left atrium (LA) was reconstructed with electroanatomical mapping system (CARTO XP). Bipolar electrograms recorded during 2.5 second were analyzed using CFAE software module. The algorism was customized to demonstrate the classification as follows in Interval confidence level (ICL) map. Sites with continuous or transient fractionated atrial potentials were colored red. Sites with irregular amplitude, polarity, cycle length but not rapid were colored green. Sites with slow organized atrial potential were purple. The sites where vagal response was evoked by high-frequency stimulation were identified as GP sites and marked on the geometry. Result: A total of 1,107 points were taken in LA. Among a total of 197 GP points, 139 (77.2%) points were in colored red and categorized as in CFAE area. GP points in colored purple categorized as in slow organized area were only 4 points (2.3%). Conclusion: The Ganglionated Plexi is strongly related to CFAE.

The antifibrillatory effect of ganglionated plexi (GP) ablation is not well established. The aim of this study was to evaluate the factors associated with termination during GP ablation in patient with paroxysmal AF. Methods: Thirty-two consecutive paroxysmal AF patients (age 61±10 years, 25 male) who underwent the selective GP ablation guided by high frequency stimulation (HFS) were enrolled in this study. The five major left atrial GP were localized by delivering HFS (20 Hz, 20 V, 10 ms pulse width). Radiofrequency current is then applied to that site to eliminate the parasympathetic response. We ablated GP first, and antrum PV electrical isolation (APVI) adjunctively. We measured cycle length (CL) in each PV, left atrial appendage (LAA), coronary sinus (CS), RA, during AF before any ablation. We investigated the termination of AF in relation with GP ablation. Results: AF was induced and sustained in 29 patients. AF terminated during GP ablation in 14 patients (48%), during APVI in 6 patients (21%). Two of 3 patients without sustained AF had SVC foci. The LAA and CS AFCL (142±22 ms, 138±19 ms) in 9 patients without termination were shorter than that in 20 patients with termination (170±33 ms, 171±27 ms, p

A 60-year-old man was hospitalized to receive percutaneous catheter pulmonary vein (PV) isolation for the treatment of drug refractory paroxysmal atrial fibrillation. We constructed a translucent volume-rendering image by multi-detector computed tomography (MDCT) which can clearly delineate the conjugation between PVs and left atrium. This translucent MDCT image can be rotated in anyway so that we can display in the same views of angiography. In the right anterior …