著者
Jun Oikawa Hidehira Fukaya Shinichi Niwano Daiki Saito Tetsuro Sato Gen Matsuura Yuki Arakawa Yuki Shirakawa Shuhei Kobayashi Ai Horiguchi Ryo Nishinarita Naruya Ishizue Jun Kishihara Junya Ako
出版者
International Heart Journal Association
雑誌
International Heart Journal (ISSN:13492365)
巻号頁・発行日
vol.61, no.4, pp.838-842, 2020-07-30 (Released:2020-07-30)
参考文献数
11

Complex atrial tachycardias (ATs) after catheter ablation or a MAZE procedure is sometimes difficult to determine the circuits of the tachycardia. A high-density, grid-shapes mapping catheter has been launched, which can be useful for detecting the detail circuits of tachycardias on three-dimensional mapping systems. The signal quality is also important for performing electrophysiological studies (EPSs), such as entrainment mapping, to identify the circuit. This unique mapping catheter has 1 mm electrodes on 2.5 Fr shafts, which improve the signal quality. The high-quality intracardiac electrograms facilitate differentiating small critical potentials, which allows us to perform detailed entrainment mapping in targeted narrow areas. Here, we describe a patient with a perimetral AT with epi-endocardium breakthrough after a MAZE surgery and catheter ablation, which was treated successfully along with detailed entrainment mapping using the HD Grid. This catheter with high-quality signals could be a significant diagnostic tool for a classic EPS as well as for the construction of 3D mapping.
著者
Shinichi Niwano Hiroe Niwano Sae Sasaki Hidehira Fukaya Masaru Yuge Ryuta Imaki Yoji Machida Tohru Izumi
出版者
The Japanese Circulation Society
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
vol.75, no.3, pp.662-671, 2011 (Released:2011-02-25)
参考文献数
34
被引用文献数
10 10

Background: Electrical and structural remodeling, characterized by prolonged action potential duration (APD), Kv4.2 downregulation and cellular infiltration were studied in rat experimental autoimmune myocarditis (EAM). Because the reactive oxygen species (ROS) has been speculated to play a role in the promotion of such remodeling, the effect of N-acetylcysteine (NAC) on the progression of ventricular remodeling was evaluated. Methods and Results: Six-week-old Lewis rats were immunized with porcine cardiac myosin. On Days 10-11 after the immunization, NAC (0, 1, 10, or 100mg) was injected intraperitoneally to EAM and control rats. On Day 14, the electrophysiological parameters were evaluated and the expression levels of the mRNA were examined by quantitative real-time reverse-transcription polymerase chain reaction (RT-PCR).The EAM rats exhibited a typical acute myocarditis with prolonged APD and reduced Kv4.2 expression as previously reported. The myocarditis and electrical changes were significantly suppressed by NAC-treatment in a dose-dependent manner (P<0.05). In rats with 100mg NAC, the myocarditis was almost totally negated although the mortality increased. In rats with 1mg NAC, the suppression of myocarditis was not obvious, but APD prolongation and Kv4.2 reduction was attenuated (P<0.05). Conclusions: The NAC treatment suppressed ventricular remodeling in the EAM rats. This may indicate the role of oxidative stress in causing remodeling and myocarditis itself in the acute phase of myocarditis. (Circ J 2011; 75: 662-671)
著者
Jun Oikawa Shinichi Niwano Hidehira Fukaya Hironori Nakamura Tazuru Igarashi Tamami Fujiishi Naruya Ishizue Tomoharu Yoshizawa Akira Satoh Jun Kishihara Masami Murakami Junya Ako
出版者
日本循環器学会
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
vol.81, no.6, pp.788-793, 2017-05-25 (Released:2017-05-25)
参考文献数
23
被引用文献数
2

Background:Distinction of paroxysmal atrial fibrillation (PAF) from non-PAF is important in clinical practice, but this is often difficult at the time of first documented AF. Given that fibrillation cycle length (FCL) is longer in PAF than in non-PAF, the aim of this study was to compare various clinical parameters including FCL to establish a scoring system to distinguish PAF and non-PAF.Methods and Results:The subjects consisted of 382 consecutive patients with AF on digital ECG at the present institute between 2008 and 2011. They were divided into PAF and non-PAF groups according to the following clinical course. Propensity score matching yielded 88 matched patient pairs with similar mean age and gender between the 2 groups. FCL was evaluated using customized fibrillation wave analyzer with fast Fourier transform analysis. On multivariate analysis, higher HR, longer FCL, and smaller LAD were independent predictors of PAF. For the scoring, cut-offs for each parameter were determined according to highest sensitivity and specificity on the ROC curves, and 1 point assigned for each parameter. Using this scoring system, 2 points detected PAF with 64% sensitivity and 84% specificity.Conclusions:We propose a scoring system including FCL to distinguish PAF from non-PAF. Further studies are needed to validate the results.
著者
Ichiro Takeuchi Hideo Fujita Kazuhiko Ohe Ryuta Imaki Nobuhiro Sato Kazui Soma Shinichi Niwano Tohru Izumi
出版者
一般社団法人 インターナショナル・ハート・ジャーナル刊行会
雑誌
International Heart Journal (ISSN:13492365)
巻号頁・発行日
vol.54, no.1, pp.45-47, 2013 (Released:2013-02-20)
参考文献数
13
被引用文献数
3 10

It is important for myocardial infarction patients to undergo immediate reperfusion of the affected coronary artery. In order to improve the prognosis, efforts to shorten the door to balloon time to within 90 minutes have been made. However, conventional methods such as faxing electrocardiograms (ECG) have not become widespread due to their high cost and lack of sharpness of the ECG. The “Doctor Car” (rapid response car system) of Kitasato University Hospital is now equipped with a Mobile Cloud ECG system. With this system, 12-lead ECG data obtained in the field are transmitted to the cloud server via a standard mobile telephone network. Since it uses an existing phone network, the cost of this system is low and it is fairly reliable. Cardiologists at the hospital read the ECG waveforms on the cloud server and decide whether emergency cardiac catheterization is necessary. In our fi rst case using this Mobile Cloud ECG system, the door to balloon time could be shortened.