Publications by authors named "Masayasu Hiraoka"

125 Publications

Long-term prognosis in patients with non-type 1 Brugada electrocardiogram: Results from a large Japanese cohort of idiopathic ventricular fibrillation.

Ann Noninvasive Electrocardiol 2021 Feb 19:e12831. Epub 2021 Feb 19.

Department of Internal Medicine, Cardiovascular Division, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Japan.

Background: Brugada syndrome (BrS) is diagnosed in patients with ST-segment elevation with spontaneous, drug-induced, or fever-induced type 1 morphology. Prognosis in type 2 or 3 Brugada electrocardiogram (Br-ECG) patients remains unknown. The purpose of this study is to evaluate long-term prognosis in non-type 1 Br-ECG patients in a large Japanese cohort of idiopathic ventricular fibrillation (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]).

Methods: From 567 patients with Br-ECG in J-IVFS, a total of 28 consecutive non-type 1 patients who underwent programmed electrical stimulation (PES) (median age: 58 years, all male, previous sustained ventricular tachyarrhythmias [VTs] 1, syncope 11, asymptomatic 16) were enrolled. Cardiac events (CEs: sudden cardiac death or sustained VT/ventricular fibrillation) during the follow-up period were examined.

Results: During a median follow-up of 136 months, four patients (14%) had CEs. None of patients with PES- have experienced CEs. There was no statistically significant clinical risk factor for the development of CEs. Using the Kaplan-Meier method, the event-free rate significantly decreased in a group with all 3 risk factors (symptom, wide QRS complex in lead V , and positive PES) (p = .01).

Conclusions: Our study revealed long-term prognosis in patients with non-type 1 Br-ECG. The combination analysis of these risk factors may be useful for the risk stratification of CEs in non-type 1 Br-ECG patients. The present study suggests that the patients with all these parameters showed high risk for CEs and need to be carefully followed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/anec.12831DOI Listing
February 2021

Risk stratification in asymptomatic patients with Brugada syndrome: Utility of multiple risk factor combination rather than programmed electrical stimulation.

J Cardiovasc Electrophysiol 2021 Feb 29;32(2):507-514. Epub 2020 Dec 29.

Cardiovascular Division, Department of Internal Medicine, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Japan.

Background: The prognostic value of programmed electrical stimulation (PES) in Brugada syndrome (BrS) remains controversial. Asymptomatic BrS patients generally have a better prognosis than those with symptoms. The purpose of this study was to evaluate the value of nonaggressive PES with up to two extra stimuli and predict clinical factors for risk stratification in asymptomatic BrS patients.

Methods: The study enrolled 193 consecutive asymptomatic BrS patients with type 1 ECG (mean age: 50 ± 13 years, 180 males) who underwent PES using a nonaggressive uniform protocol. Cardiac events (CEs: sudden cardiac death or ventricular tachyarrhythmia) during the follow-up period were examined.

Results: During a mean follow-up of 101 ± 48 months, seven asymptomatic patients (3.6%) had a CE. The incidence of CEs was not different between patients with and without inducible ventricular tachyarrhythmia by PES (p = .51). The clinical significance of risk factor combinations, including spontaneous type 1 ECG, family history of sudden cardiac death, QRS duration in lead V , and presence of J wave, was evaluated. Using the Kaplan-Meier method according to the number of risk factors, the prevalence of CE in patients with three or four risk factors was determined to be significantly higher than in those with one risk factor (p = .02 and p = .004, respectively).

Conclusions: The present study suggests that inducibility of ventricular tachyarrhythmia does not predict future CEs in asymptomatic BrS patients. Combination analysis of the other four clinical risk parameters may be effective for risk assessment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jce.14848DOI Listing
February 2021

The coronary artery calcium score correlates with left atrial low-voltage area: Sex differences.

J Cardiovasc Electrophysiol 2021 01 29;32(1):41-48. Epub 2020 Nov 29.

Tokyo Medical and Dental University, Tokyo, Japan.

Introduction: In patients with coronary artery disease, a high coronary artery calcium score (CACS) correlates with atrial fibrillation (AF); however, the association between left atrial (LA) remodeling progression and coronary arteriosclerosis is unclear. This study aimed to evaluate the relationship between LA remodeling progression and the CACS.

Methods: This retrospective study enrolled 148 patients with AF (paroxysmal AF, n = 94) who underwent catheter ablation. Voltage mapping for the left atrium and coronary computed tomography for CACS calculations were performed. The ratio of the LA low-voltage area (LA-LVA), defined by values less than 0.5 mV divided by the total LA surface without pulmonary veins, was calculated. Patients with LA-LVA (<0.5 mV) >5% and ≤5% were classified as the LVA (n = 30) and non-LVA (n = 118) groups, respectively. Patient characteristics and CACS values were compared between the two groups.

Results: LA volume, age, CHA DS VASc score, and percentage of female patients were significantly higher, and the estimated glomerular filtration rate was lower in the LVA group than in the non-LVA group. The CACS was significantly higher in the LVA group (248.4 vs. 13.2; p = .001). Multivariate analysis identified the LA volume index and CACS as independent predictors of LA-LVA (<0.5 mV) greater than 5%. The areas under the receiver operating characteristic curves for predicting LA-LVA (<0.5 mV) greater than 5% with CACS were 0.695 in the entire population, 0.782 in men, and 0.587 in women.

Conclusion: Progression of LA remodeling and coronary artery calcification may occur in parallel. A high CACS may indicate advanced LA remodeling, especially in men.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jce.14822DOI Listing
January 2021

Quality of life improvements by durable pulmonary vein isolation in patients with atrial fibrillation.

J Cardiovasc Electrophysiol 2020 08 4;31(8):2013-2021. Epub 2020 Jun 4.

Department of Cardiovascular Disease, Tokyo Medical and Dental University, Tokyo, Japan.

Introduction: Successful pulmonary vein isolation (PVI) can improve the quality of life (QOL) of patients with atrial fibrillation (AF). However, the role of durable PVI for such QOL improvement is not known. The aim of this study was to clarify the effectiveness of durable PVI in improving the QOL of patients with AF.

Methods And Results: We assessed 119 patients who underwent PVI (age 66.4 ± 9.6 years, 104 paroxysmal AF). A scheduled electrophysiological study was performed 6 months after the first PVI session-regardless of recurrence of AF-to assess the durability of PVI and to identify and re-isolate reconnected pulmonary veins. QOL scores were evaluated by an AF-specific QOL questionnaire and checked at baseline, 6  months, and 1 year after the first session. In patients without AF recurrence (nonrecurrence group, n = 93), the scores at 6 months improved compared with those at baseline; conversely, the scores did not improve in patients with AF recurrence (n = 26). Nevertheless, the scores at 1 year improved compared with those at 6 months in both groups. Within the nonrecurrence group, the score difference between 6 months and baseline was higher in the durable PVI group (n = 58) than that in the nondurable PVI group (n = 35).

Conclusions: The QOL of AF patients improved by the resumption of sinus rhythm following PVI. Patients with durable PVI had increased QOL scores compared with those with nondurable PVI. The durability of PVI may achieve further improvements in the QOL of patients with AF.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jce.14592DOI Listing
August 2020

Comparison of touch-up ablation rate and pulmonary vein isolation durability between hot balloon and cryoballoon.

J Cardiovasc Electrophysiol 2020 06 20;31(6):1298-1306. Epub 2020 Apr 20.

Tokyo Medical and Dental University, Tokyo, Japan.

Introduction: This study aimed to compare touch-up ablation (TUA) rates and pulmonary vein isolation (PVI) durability of hot balloon ablation (HBA) and cryoballoon ablation (CBA) in paroxysmal atrial fibrillation (PAF) patients.

Methods: In total, 137 PAF patients were enrolled in the study. Among them, 59 underwent two HBA procedures at 6-month intervals and 78 patients underwent two CBA sessions, both regardless of atrial fibrillation recurrence. Propensity score matching was performed to estimate similar patient characteristics between the HBA and CBA groups.

Results: Each group comprised of 46 matched patients for comparison. The TUA rate at the first session was higher for HBA (49 of 184 PVs) than for CBA (20 PVs) (P = .01), with the highest incidence at the left superior pulmonary vein (LSPV). The rates of PVI durability at the second session performed 7 months later were similar between HBA (168 of 184 PVs) and CBA (162 PVs) groups. The PVI durability rate at the TUA sites of the first session was higher for HBA than for CBA (41 of 49 PVs vs 10 PVs, respectively; P = .01). Fifty percent of the patients underwent HBA at 73°C for the LSPV. HBA performed at 73°C yielded a lower TUA rate than that at 70°C (16 of 23 PVs vs 7 of 23 PVs; P = .008).

Conclusions: While PVI durability was similar between HBA and CBA, the TUA rate was higher for HBA than for CBA, especially on the LSPV. For LSPV, HBA at a balloon temperature of 73°C may reduce the TUA rate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jce.14485DOI Listing
June 2020

Recurrent ischemic stroke in patients with atrial fibrillation ablation and prior stroke: A study based on etiological classification.

J Arrhythm 2020 Feb 3;36(1):95-104. Epub 2019 Dec 3.

Tokyo Medical and Dental University Tokyo Japan.

Background: Different subtypes of ischemic stroke may have different risk factors, clinical features, and prognoses. This study investigated the incidence and mode of stroke recurrence in patients with a history of stroke who underwent atrial fibrillation (AF) ablation.

Methods: Of 825 patients who underwent AF ablation from 2006 to 2016, 77 patients (9.3%, median age 69 years) with a prior ischemic stroke were identified. Patients were classified as those with prior cardioembolic (CE) stroke (n = 55) and those with prior non-CE stroke (n = 22). The incidence and pattern of stroke recurrence were investigated.

Results: The incidence of asymptomatic AF (54.5% vs 22.7%;  = .011) and left atrial volume (135.8 mL vs 109.3 mL;  = .024) was greater in the CE group than in the non-CE group. Anticoagulation treatment was discontinued at an average of 28.1 months following the initial ablation in 34 (44.2%) patients. None of the patients developed CE stroke during a median 4.1-year follow-up. In the non-CE group, 2 patients experienced recurrent non-CE stroke (lacunar infarction in 1 and atherosclerotic stroke in 1); however, AF was not observed at the onset of recurrent ischemic stroke.

Conclusions: In patients with a history of stroke who underwent catheter ablation for AF, the incidence of recurrent stroke was 0.54/100 patient-years. The previous stroke in these patients may not have been due to AF in some cases; therefore, a large-scale prospective study is warranted to identify the appro priate antithrombotic therapy for the prevention of potentially recurrent stroke.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/joa3.12285DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7011801PMC
February 2020

Catheter ablation for monomorphic ventricular tachycardia in Brugada syndrome patients: detailed characteristics and long-term follow-up.

J Interv Card Electrophysiol 2020 Jan 12;57(1):97-103. Epub 2019 Oct 12.

Department of Cardiology, Tokyo Medical Dental University, Tokyo, Japan.

Purpose: Brugada syndrome (BrS) is a risk of sudden cardiac death due to polymorphic ventricular tachycardia and ventricular fibrillation with unusual monomorphic ventricular tachycardia (MVT). Detailed characteristics of MVT and long-term outcome of catheter ablation are still unknown. This study is aimed to identify the detailed characteristics and long-term follow-up of catheter ablation in BrS patients.

Methods: We evaluated 188 patients who were diagnosed with BrS from March 1999 to March 2018. Of those, patients who developed MVT and underwent catheter ablation were included. We identified eight MVTs in seven BrS patients.

Results: Three of them already had implantable cardioverter-defibrillator, and MVTs were terminated by cardioversion or anti-tachycardia pacing. Four patients presented with MVT originating from the right ventricular outflow tract, one patient had MVT arising from the LV septum, one patient had MVT arising from the tricuspid annulus, and one patient had bundle branch reentry ventricular tachycardia. All MVTs were successfully treated by catheter ablation in the acute phase, and seven of eight (87.5%) were free from ventricular tachyarrhythmia during the long-term follow-up (median, 7.2 years).

Conclusions: All MVT cases were successfully treated by catheter ablation. We observed high ventricular arrhythmia free rate following catheter ablation during the long-term follow-up period. BrS patients who developed MVT should consider catheter ablation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10840-019-00620-0DOI Listing
January 2020

Characteristics of Marshall bundle-related atrial tachycardias using an ultrahigh-resolution mapping system.

J Interv Card Electrophysiol 2019 Aug 23;55(2):161-169. Epub 2019 Apr 23.

Tokyo Medical and Dental University, Tokyo, Japan.

Purpose: Marshall bundle (MB)-related atrial tachycardias (ATs) have already been described; however, their characteristics using an ultrahigh-resolution mapping system are not yet well known. The purpose of this study was to clarify the characteristics of MB-related ATs with ultrahigh-resolution mapping.

Methods: In 28 patients who underwent an electrophysiological study for ATs using an ultrahigh-resolution mapping system, precise circuits of 37 ATs were detected. Among those ATs, five were diagnosed as MB-related ATs that had epicardial connections among the reentrant circuits (mean age 76.6 ± 3.7 years, one male patient). We analyzed the characteristics of those MB-related ATs with ultrahigh-resolution mapping.

Results: The mean cycle length was 260 ± 60 ms, and the total acquired electrograms were 12,962 ± 2616 points. Two ATs were perimitral ATs, two rotated around the left pulmonary vein (PV), and one rotated around the left inferior PV. All ATs had a centrifugal activation pattern: 5 o'clock on the mitral annulus in four ATs and the upper ridge in one. Tiny potentials, which indicated epicardial potentials covering the cycle length, were detected in four of five ATs. The local activation times covered over 95% of the tachycardia cycle length on the endocardial side only in all ATs. All ATs were terminated during a radiofrequency ablation from the endocardial side of the Marshall bundle.

Conclusions: The ultrahigh-resolution mapping system demonstrated an activation map of MB-related ATs with a centrifugal pattern. Macroreentrant tachycardias with a centrifugal activation pattern should be considered as possible MB-related ATs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10840-019-00544-9DOI Listing
August 2019

The Horizon and History of Asia Pacific Heart Rhythm Society.

Authors:
Masayasu Hiraoka

J Arrhythm 2019 Feb 5;35(1):1-6. Epub 2018 Oct 5.

Tokyo Medical and Dental University Tokyo Japan.

The Asia Pacific Heart Rhythm Society (APHRS) has grown very rapidly and efficiently after its founding in 2008. The success of our organization and rapid growth was due to the enthusiastic support by pioneer electrophysiologists and efforts by many physicians to cure heart rhythm disorders. With the experience of preceding arrhythmia symposia of inter-cities or international basis in the region, the organization could quickly grow to become APHRS. The mission of APHRS is to promote basic research and improve clinical practice, optimize care of patients with heart rhythm disorders, and to train and encourage young physicians to actively participate and promote the activity of our society.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/joa3.12121DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6373642PMC
February 2019

Characteristics of ventricular intracardiac electrograms of ventricular tachycardias originating from the epicardia in patients with an implantable cardioverter defibrillator.

J Cardiovasc Electrophysiol 2019 04 2;30(4):575-581. Epub 2019 Feb 2.

Department of Cardiology, Tokyo Medical and Dental, University, Tokyo, Japan.

Introduction: While characteristic waveforms of 12-lead electrocardiograms have been reported to predict the epicardial origin of ventricular tachycardia (VT), it has not been fully examined whether ventricular intracardiac electrograms (VEGMs) recorded from the implantable cardioverter defibrillator (ICD) via telemetry can determine the origin of VT or not. The aim of this study was to investigate the VEGM characteristics of VT originating from the epicardia.

Method And Results: Intracardiac VEGMs of the induced VTs, with detected sites of origin during the VT study, were recorded in 15 (23 VTs) of the 46 patients. The characteristics of the 23 VTs were evaluated using far-field and near-field VEGMs recorded via telemetry. Five of 23 VTs were found to be focused on the epicardial site (epi group) and 18 VTs were focused on the endocardium (endo group). VTs of the epi group had longer VEGM duration in far-field EGM than those of the endo group (epi group: 240 ± 49 ms vs endo group: 153 ± 45 ms; P = 0.002) and the duration from the onset to the peak of VEGM was also longer than that of the endo group (epi group: 153 ± 53 ms vs endo group: 63 ± 28 ms; P < 0.001). There was no difference in the V wave duration in tip-ring EGM between both groups (epi group: 122 ± 52 ms vs endo group: 98 ± 6 ms; P = 0.377).

Conclusion: Evaluation of intracardiac VEGM before VT ablation may be helpful to predict the epicardial origin of VT in patients with an ICD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jce.13854DOI Listing
April 2019

A pseudo-sinus rhythm due to bigeminal ectopy with the focus in the right superior pulmonary vein.

HeartRhythm Case Rep 2018 Nov 4;4(11):553-555. Epub 2018 Aug 4.

Department of Cardiovascular Disease, Tokyo Medical and Dental University, Tokyo, Japan.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.hrcr.2018.07.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6241170PMC
November 2018

Adenosine-sensitive atrial tachycardia originating from the anterior mitral annulus.

HeartRhythm Case Rep 2018 Nov 14;4(11):542-544. Epub 2018 Aug 14.

Department of Cardiovascular Diseases, Tokyo Medical and Dental University, Tokyo, Japan.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.hrcr.2018.08.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6241165PMC
November 2018

The relationship between obstructive sleep apnea and recurrence of atrial fibrillation after pulmonary vein isolation using a contact force-sensing catheter.

J Interv Card Electrophysiol 2019 Apr 20;54(3):209-215. Epub 2018 Nov 20.

Tokyo Medical and Dental University, Tokyo, Japan.

Purpose: Our aim was to elucidate the relationship between obstructive sleep apnea (OSA) and atrial fibrillation (AF) recurrence after repeated pulmonary vein isolation (PVI).

Methods: We conducted a non-randomized observational study, with the data prospectively collected. One hundred patients (paroxysmal AF, n = 89) underwent PVI using a contact force-sensing catheter. All patients underwent an electrophysiological study and additional ablation for left atrium-pulmonary vein (PV) reconnection and non-PV foci, 6 months after the first treatment session, regardless of AF recurrence. Those with an apnea-hypopnea index ≥ 15 were diagnosed with OSA. Continuous positive air pressure (CPAP) therapy was initiated after the second treatment session, based on results of a sleep study. For analysis, patients were classified into the non-OSA (n = 66), treated OSA (OSA patients undergoing CPAP; n = 11), and untreated OSA (n = 23) groups, and between-group differences evaluated.

Results: After the first session, AF recurrence was observed in 18.2% (12/66) and 14.7% (5/34) of patients without and with OSA, respectively (P = 0.678). After the second procedure, the rate of AF recurrence was 12.1% (8/66) in the non-OSA group, 9.1% (1/11) in the treated OSA group, and 8.7% (2/23) in the untreated OSA group (log-rank P = 0.944).

Conclusions: The rate of AF recurrence might not be greater in patients with untreated OSA than in those without OSA and those with treated OSA after repeated PVI, using a contact force-sensing catheter, for patients with paroxysmal or short-term persistent AF.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10840-018-0489-xDOI Listing
April 2019

Ventricular Fibrillation Induced by Coronary Vasospasm in a Patient with Early Repolarization and Hyperthyroidism.

Intern Med 2018 Dec 10;57(23):3389-3392. Epub 2018 Aug 10.

Tokyo Medical and Dental University, Japan.

Vasospastic angina (VSA) has been recognized as a cause of ventricular fibrillation (VF) degenerating into sudden cardiac death. We experienced a case of VSA with hyperthyroidism in which VF was provoked with an augmented J-wave amplitude in the inferior leads. The patient underwent insertion of an implantable cardioverter-defibrillator for the secondary prevention of VF in addition to taking Ca-channel antagonists. He has shown no recurrence of fatal arrhythmia or anginal attack for a follow-up period of one year.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2169/internalmedicine.1104-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6306529PMC
December 2018

Ajmaline-induced Epsilon wave: as a potential interim risk factor between the spontaneous and drug-induced type 1 Brugada electrogram?- Authors' reply.

Europace 2018 07;20(7):1226

Cardiovascular Division, Department of Internal Medicine, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Japan.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/europace/euy108DOI Listing
July 2018

Development of Nonpulmonary Vein Foci Increases Risk of Atrial Fibrillation Recurrence After Pulmonary Vein Isolation.

JACC Clin Electrophysiol 2017 06 1;3(6):547-555. Epub 2017 Feb 1.

Tokyo Medical and Dental University, Tokyo, Japan.

Objectives: The aim of this paper was to clarify the impact of nonpulmonary vein foci (NPVF) on atrial fibrillation (AF) recurrence after pulmonary vein (PV) isolation.

Background: NPVF are considered contributing factors for the recurrence of AF after PV isolation, but their exact role remains unclear.

Methods: We retrospectively reviewed 216 patients (paroxysmal AF, n = 172; persistent AF, n = 44) who underwent a second electrophysiological study 6 months after the original PV isolation. Patients with AF recurrence underwent additional ablation procedures for reconnected PV and NPVF. NPVF were detected in the control group and with drug infusion (isoproterenol or isoproterenol with adenosine triphosphate) during the first and second procedure. NPVF detected for the first time in the second session were defined as newly developed, and their effect on AF recurrence after the second procedure was investigated, along with the predictive factors for NPVF development.

Results: Patients with AF recurrence after the first session had a significantly higher reconnected PV (91.5% vs. 68.2% in patients without recurrence). NPVF were detected in 20 and 54 patients in the first and second sessions, respectively. Patients with newly developed NPVF had a significantly higher AF recurrence (24.1% vs. 7.4% in patients without newly developed NPVF). Newly developed NPVF and AF recurrence after the first session were independent predictors for AF recurrence after the second procedure, whereas AF history and NPVF in the first session were independent predictors for newly developed NPVF.

Conclusions: NPVF detection and ablation may represent important therapeutic options to prevent AF recurrence, especially in patients who require repeated procedures.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jacep.2016.12.008DOI Listing
June 2017

Ventricular tachycardia storm originating from interventricular septum successfully treated with surgical cryoablation with electroanatomic and electrophysiological mapping before dual valve replacement.

J Arrhythm 2018 Feb 21;34(1):71-73. Epub 2017 Dec 21.

Tokyo Medical and Dental, University Tokyo Japan.

A 58-year-old man with dilated cardiomyopathy was admitted with heart failure. He had a history of two catheter ablation procedures for ventricular tachycardia (VT) originating from the intraventricular septum (IVS). Before dual valve replacement (DVR), he suffered a VT storm. An electrophysiological study revealed an extended low-voltage area at the IVS with the exit of the induced VT at the anterior side. Radiofrequency application was performed at the VT exit as a landmark for surgical cryoablation (SA). During the DVR, SA was performed at the IVS using this landmark. After SA, the patient had no ventricular tachyarrhythmia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/joa3.12020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5828278PMC
February 2018

Successful catheter ablation of ventricular premature complexes from the right atrial side of the atrioventricular septum with good contact force.

J Arrhythm 2018 04 12;34(2):201-203. Epub 2018 Mar 12.

Department of Cardiovascular Diseases Tokyo Medical and Dental University Bunkyō Tokyo Japan.

The acquisition of good contact force for radiofrequency catheter ablation of ventricular premature complexes (VPCs) originating from the basal septum of the left ventricle (LV) is often difficult. We describe a case of VPCs originating from the basal septum of the LV, which were successfully eliminated by applying radiofrequency at the right atrium (RA) side of the atrioventricular septum (AVS) without causing any significant impairment of atrioventricular conduction because the ablation catheter could obtain better contact force through the RA approach. Moreover, intracardiac echocardiography (ICE) and RA angiography effectively demonstrated the AVS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/joa3.12038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5891414PMC
April 2018

The prognostic impact of single extra-stimulus on programmed ventricular stimulation in Brugada patients without previous cardiac arrest: multi-centre study in Japan.

Europace 2018 07;20(7):1194-1200

Department of Internal Medicine, Cardiovascular Division, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Japan.

Aims: The prognostic value of programmed electrical stimulation (PES) in Brugada syndrome (BrS) remains controversial. One of the reasons for discrepant results may be due to the selection of stimulation protocol. We evaluated the prognostic value of a positive PES result (PES+) according to the inducible pacing sites and the number of extra-stimuli in BrS patients without previous cardiac arrest (CA).

Methods And Results: We enrolled 224 consecutive BrS patients without previous CA (mean age 51 ± 14 years, 209 males), who underwent PES with the identical protocol. Clinical outcomes of development of CA were explored in the patients with and without PES+ according to sites and number of extra-stimuli. During a mean follow-up period of 76 months, 12 cardiac events (CE: sudden cardiac death or documented VF) occurred (8 with and 4 without PES+). The incidence of CE was not different in patients with and without PES+, those with PES+ from RVA (n = 72) or RVOT (n = 60), and those with and without PES+ by up to 2 extra-stimuli (n = 58). However, in patients that were PES+ by a single extra-stimulus (n = 8) the incidence of CE was significantly higher than in those without PES+ (8.8 vs. 0.6%/year, P < 0.0001). On univariate analysis, syncope, spontaneous type 1 ECG, and PES+ by a single extra-stimulus were associated with CE.

Conclusion: Details of the stimulation protocol may be important for risk assessment in BrS patients without previous CA. A single extra-stimulus may be useful in stratifying risk in patients with spontaneous type 1 ECG and syncope.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/europace/eux096DOI Listing
July 2018

Usefulness of epicardial impedance evaluation for epicardial mapping and determination of epicardial ablation site for ventricular tachycardia: A pilot study.

J Cardiovasc Electrophysiol 2018 01 1;29(1):138-145. Epub 2017 Nov 1.

Toride Kitasoma Medical Center Hospital, Ibaraki, Japan.

Background: During epicardial mapping, determination of appropriate ablation sites in low voltage areas (LVA) is challenging because of large epicardial areas covered by adipose tissue.

Objective: To evaluate the impedance difference between epicardial fat and the epicardial LVA using multiple detector computed tomography (MDCT).

Methods: We enrolled patients who underwent ventricular tachycardia (VT) ablation via the epicardial approach after endocardial ablation failure. After the procedure, MDCT-derived images of epicardial fat were loaded to the mapping system. Then, all points acquired during sinus rhythm were retrospectively superimposed and analyzed.

Results: This study included data from 7 patients (62.5 ± 3.9 years old) who underwent eight epicardial VT ablation procedures. After the procedure, MDCT-derived images of epicardial fat were registered in eight procedures. Retrospective analysis of 1,595 mapping and 236 ablation points was performed. Of the 1,595 mapping points on the merged electroanatomical and epicardial fat maps, normal voltage area (NVA) and low voltage area (LVA) without fat had lower impedance than those with fat (NVA without fat 182 ± 46 Ω vs. NVA with fat 321 ± 164.0 Ω, P  =  0.001, LVA without fat 164 ± 69 Ω vs. LVA with fat 248 ± 89 Ω, P  =  0.002). Of the 236 ablation points, initial impedance before ablation was higher on epicardial fat than on epicardial LVA without fat (134 ± 16 Ω vs. 156 ± 28 Ω, P  =  0.01).

Conclusions: Real time epicardial impedance evaluation may be useful to determine effective epicardial ablation sites and avoid adipose tissue. However, the number of patients in the present study is limited. Further investigation with a large number of patients is needed to confirm our result.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jce.13361DOI Listing
January 2018

Reply: Takotsubo syndrome and polymorphic ventricular tachycardia: The chicken or the egg.

J Arrhythm 2017 Feb 24;33(1):79. Epub 2016 Jun 24.

Toride Kitasohma Medical Center Hospital, Ibaraki, Japan.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.joa.2016.04.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5300839PMC
February 2017

Outcomes of Brugada Syndrome Patients with Coronary Artery Vasospasm.

Intern Med 2017 15;56(2):129-135. Epub 2017 Jan 15.

Department of Cardiology, Yokohama General Hospital, Japan.

Objective To evaluate the outcomes of patients with concomitant Brugada syndrome and coronary artery vasospasm. Methods Patients diagnosed with Brugada syndrome with an implantable cardiac defibrillator were retrospectively investigated, and the coexistence of vasospasm was evaluated. The clinical features and outcomes were evaluated, especially in patients with coexistent vasospasm. A provocation test using acetylcholine was performed in patients confirmed to have no organic stenosis on percutaneous coronary angiography to confirm the presence of vasospasm. Implantable cardiac defibrillator shock status was checked every three months. Statistical comparisons of the groups with and without vasospasm were performed. A univariate analysis was also performed, and the odds ratio for the risk of implantable cardiac defibrillator shock was calculated. Patients Thirty-five patients with Brugada syndrome, of whom six had coexistent vasospasm. Results There were no significant differences in the laboratory data, echocardiogram findings, disease, or the history of taking any drugs between patients with and without vasospasm. There were significant differences in the clinical features of Brugada syndrome, i.e. cardiac events such as resuscitation from ventricular fibrillation or appropriate implantable cardiac defibrillator shock. Four patients with vasospasm had cardiac events such as resuscitation from ventricular fibrillation and/or appropriate defibrillator shock; three of them had no cardiac events with calcium channel blocker therapy to prevent vasospasm. The coexistence of vasospasm was a potential risk factor for an appropriate implantable cardiac defibrillator shock (odds ratio: 13.5, confidence interval: 1.572-115.940, p value: 0.035) on a univariate analysis. Conclusion Coronary artery vasospasm could be a risk factor for cardiac events in patients with Brugada syndrome.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2169/internalmedicine.56.7307DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5337455PMC
March 2017

Life-Threatening Ventricular Arrhythmia and Brugada-Type ST-Segment Elevation Associated With Acute Ischemia of the Right Ventricular Outflow Tract.

Circ J 2017 Feb 11;81(3):322-329. Epub 2017 Jan 11.

Department of Cardiology, Yokohama Minami Kyosai Hospital.

Background: Brugada-type ECG (Br-ECG) is occasionally observed during acute myocardial ischemia of the right ventricular outflow tract (RVOT). No studies have explored, however, the association of ventricular tachyarrhythmia and development of Br-ECG due to acute ischemia of the RVOT.Methods and Results:The study included 13 consecutive patients with acute ischemia of the RVOT during coronary catheterization. Patients were divided into 2 groups: those with Br-ECG (group B) and those without (group N). The proportion of male patients was higher in group B than in group N (100% vs. 25%, P<0.01), and VT/VF developed in only patients with Br-ECG (group B). In group B, VT/VF was observed in patients without pre-existing organic change in the conus/right ventricular (RV) branch of the right coronary artery and no VT/VF was seen in patients with organic coronary stenosis despite Br-ECG.

Conclusions: Acute myocardial ischemia of the RVOT caused Br-ECG predominantly in male patients and subsequent development of VT/VF in some patients. VT/VF was seen in patients without any obstructive lesion but arrhythmic events were not observed in RVOT ischemia in the case of pre-existing coronary occlusion or stenosis of the conus or RV branch, suggesting the effects of precondition.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1253/circj.CJ-16-1112DOI Listing
February 2017

Clinical Characteristics and Long-Term Prognosis of Senior Patients With Brugada Syndrome.

JACC Clin Electrophysiol 2017 01 1;3(1):57-67. Epub 2016 Jun 1.

Tokyo Metropolitan Health and Medical Treatment Corporation, Ohkubo Hospital, Tokyo, Japan.

Objectives: This study investigated clinical characteristics and prognosis of Brugada syndrome (BrS) in patients older than 60 years of age during a long-term follow-up period.

Background: Clinical characteristics and prognosis of senior patients with BrS have not been clearly elucidated.

Methods: A total of 181 patients with BrS were divided into 2 groups by age at the time of diagnosis: the younger group was <60 years of age (n = 123), and the senior group was ≥60 years of age (n = 58).

Results: Mean ages were 42.7 ± 11 years and 68.6 ± 7.1 years, respectively. Prevalence of spontaneous type 1 electrocardiogram (ECG) was lower in the senior group (22 of 58; 37.9%) than in the younger group (64 of 123; 51.9%) (p = 0.027). Among various ECG parameters, the senior group had a lower incidence of prolonged r-J intervals in V ≥90 ms than the younger group (34 of 58; 58.6% vs. 90 of 123; 73.1%, p = 0.049) and day-to-day variation of Brugada ECG patterns (3 of 58; 5.2% vs. 23 of 123; 18.7%, p = 0.032). During a mean follow-up period of 7.6 ± 5.8 years, no senior patients experienced documented fatal ventricular arrhythmias, but 11 younger patients did. Kaplan-Meier analysis revealed a better prognosis in the senior group than in the younger group (log-rank, p = 0.011).

Conclusions: Senior BrS patients, ≥60 years of age, had a better prognosis than those <60 years of age. Implantable cardioverter-defibrillator insertion for senior patients with BrS needs careful consideration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jacep.2016.04.004DOI Listing
January 2017

Middle fascicle as a common retrograde limb in two left upper septal interfascicular reentrant ventricular tachycardias: a case report.

J Interv Card Electrophysiol 2016 Dec 5;47(3):311-312. Epub 2016 Aug 5.

Tokyo Metropolitan Health and Medical Treatment Corporation Ohkubo Hospital, Tokyo, Japan.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10840-016-0169-7DOI Listing
December 2016

Long-term efficacy of catheter ablation for paroxysmal atrial fibrillation in patients with Brugada syndrome and an implantable cardioverter-defibrillator to prevent inappropriate shock therapy.

Heart Rhythm 2016 07 4;13(7):1455-9. Epub 2016 Mar 4.

Tokyo Metropolitan Health and Medical Treatment Corporation Ohkubo Hospital, Tokyo, Japan.

Background: In patients with an implantable cardioverter-defibrillator (ICD) and Brugada syndrome (BrS), the long-term efficacy of catheter ablation for preventing inappropriate shock therapy due to paroxysmal atrial fibrillation (PAF) has not been elucidated.

Objective: To evaluate the efficacy of atrial fibrillation (AF) ablation for PAF for prevention of inappropriate ICD therapy over a longer follow-up period.

Methods: We enrolled 76 men with BrS and an ICD, with a mean age of 46.2 ± 16.5 years. Twenty-one patients had AF (19 had PAF, 1 had persistent AF, and 1 had longstanding persistent AF). Fourteen patients with PAF underwent pulmonary vein isolation (PVI) and received follow-up electrophysiological study (EPS) 6 months after the first PVI. If necessary, ablation was performed.

Results: Over a mean follow-up period of 3.3 ± 1.4 years after the repeat session, 13 of the 14 patients (92.9%) had no recurrence of AF. Six patients with PAF without inappropriate ICD therapy before PVI had no recurrence of AF and no inappropriate therapy during follow-up. Among the 8 patients who had inappropriate therapy because of PAF before PVI, 1 patient who had recurrent AF underwent another ablation session. After this final session, there were no recurrences of AF and no inappropriate therapy (mean follow-up period 3.1± 1.2 years).

Conclusion: Catheter ablation is effective in patients with BrS and an ICD, and prevents inappropriate ICD therapy owing to PAF; thus, catheter ablation is an appropriate first-line therapy for PAF among such patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.hrthm.2016.03.006DOI Listing
July 2016

Peri-Mitral Atrial Tachycardia Using the Marshall Bundle Epicardial Connections.

JACC Clin Electrophysiol 2016 Feb 10;2(1):27-35. Epub 2015 Nov 10.

Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan.

Objectives: The aim of this study was to determine whether re-entrant circuits were associated with the ligament of Marshall (LOM).

Background: Peri-mitral atrial tachycardias (PMATs) following pulmonary vein isolation (PVI) or mitral valve surgery are common.

Methods: Six PMATs involving epicardial circuits were identified from 38 patients. Of these, 4 PMATs involved the LOM (PMAT-LOM, mean cycle length 308 ± 53 ms), as confirmed by the insertion of a 2-F electrode in the vein of Marshall (VOM). All patients underwent PVI and mitral isthmus ablation. The PMAT-LOMs were diagnosed based on left atrium (LA) activation maps that covered <90% of tachycardia cycle length (TCL), and a difference between the post-pacing interval and TCL that was: 1) ≤20 ms at the VOM, the ridge between the left pulmonary vein and appendage, the anterior wall of the LA, and along the 6 to 11 o'clock direction of the mitral annulus; and 2) >20 ms at the distal coronary sinus (CS), the posterior wall of the LA, and the mitral isthmus ablation line (or noncapture). Catheter ablation was performed at the ridge for all PMAT-LOMs.

Results: Three tachycardias were successfully terminated at the ridge, which showed continuous fractionated potential lasting >100 ms, confirming the bidirectional block of Marshall bundle (MB)-LA connections. The remaining tachycardia required ablation for the CS-MB connections, confirming bidirectional block of CS-MB connections.

Conclusions: PMAT-LOMs following PVI or valve surgery accounted for up to 11% of PMATs. The bidirectional block of either MB-LA or CS-MB connections is required to eliminate PMAT-LOMs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jacep.2015.08.011DOI Listing
February 2016