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ABSTRACT: This report describes a case of a patient with long QT syndrome (LQTS) with recurrent episodes of torsades de pointes (TdP). Use of biventricular pacing (BiVP) resulted in a shorter QT interval and a shorter T-peak-end interval and prevented further episodes of TdP. These findings suggest that BiVP may be helpful in patients with LQTS and refractory TdP. (PACE 2011; 1-3).
Pacing and Clinical Electrophysiology 11/2011; · 1.35 Impact Factor
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ABSTRACT: This study has evaluated whether candesartans prevent the recurrence of atrial fibrillation (AF) and decrease type III procollagen-N-peptide (PIIINP) levels. A total of 153 patients with AF were enrolled in this study. Three groups of patients were compared; candesartan group was treated with candesartan plus bepridil (n = 52); and carvedilol group with carvedilol plus bepridil (n = 51); and bepridil group with bepridil alone (n = 50). The primary end point was length of time to the recurrence of AF and all patients were ultimately followed-up for 730 days. Serum levels of the biomarkers were measured at baseline and after 24 months. Maintenance of sinus rhythm was achieved in 25 (50%) patients in bepridil group, 37 (73%) in candesartan group, and 34 (67%) in carvedilol group, giving a bepridil group/candesartan group hazard ratio of 0.36 (95% confidence interval 0.21-0.63; P = 0.03). Candesartan significantly decreased PIIINP levels at 24 months than at baseline in sinus rhythm group (0.57 +/- 0.02 vs. 0.64 +/- 0.05 U/mL, P = 0.04) and did not decrease PIIINP levels in the recurrence group. In conclusions, PIIINP might be related to the possibility of the atrial fibrosis for AF. However, further studies are needed to clarify the relationship between PIIINP and AF.
Journal of cardiovascular pharmacology 02/2010; 55(5):511-7. · 2.83 Impact Factor
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Mutsuki Makino,
Hirokazu Honda, Fumito Miyoshi,
Yoshio Ban,
Takashi Katagiri,
Taka-Aki Matsuyama,
Hidekazu Ota,
Osamu Yoshitake,
Mitsuo Kusano,
Takanori Shibata,
Tadao Akizawa
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ABSTRACT: A previously healthy middle-aged woman noted a rapid onset of flank pain with gross hematuria. Enhanced CT scan showed thrombosis of the inferior vena cava and right renal vein. Laboratory findings revealed nephrotic proteinuria, Sjogren's syndrome (SjS), and Graves' disease (GD). A right nephrectomy was performed because of progressive and refractory renal necrosis. Renal specimens showed venous infarction with diffuse hemorrhagic and severe congestive renal necrosis, and membranous nephropathy (MN). The present case was diagnosed as acute renal necrosis due to catastrophic thrombosis in a patient with SjS, GD, and MN. It was thought that sudden development of thrombosis may have been caused by the status of the autoimmune disorders, and the associated MN.
Internal Medicine 02/2008; 47(10):969-73. · 0.94 Impact Factor
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ABSTRACT: The present study evaluated the effect of treatment renin angiotensin system inhibitors (RAS-I) for maintaining sinus rhythm after conversion from persistent atrial fibrillation. As the efficacy of RAS-I in atrial fibrillation is unclear, our study evaluated conversion to and maintenance of sinus rhythm by combination therapy with RAS-I and bepridil in patients in atrial fibrillation.
Bepridil was administered to 125 consecutive patients with paroxysmal and persistent atrial fibrillations. Two groups of patients were compared: The bepridil group was treated with bepridil alone, the RAS-I group with bepridil plus angiotensin II receptor blockers or angiotensin converting enzyme inhibitors. The primary end point was length of time to first recurrence of atrial fibrillation.
Maintenance of sinus rhythm was achieved in 25 patients (45%) in the bepridil group and 44 patients (63%) in the RAS-I group (persistent and paroxysmal atrial fibrillations). The difference between the bepridil group and the RAS-I group was significant (p < 0.05). Maintenance of sinus rhythm was achieved in 9 of 25 patients (36%) in the bepridil group, and in 22 of 35 patients (62%) in the RAS-I group with persistent atrial fibrillation. The difference between the bepridil group and the RAS-I group was significant (p < 0.05). Bepridil plus RAS-I was particularly effective at preventing the recurrence of atrial fibrillation in patients with left ventricular dysfunction (left ventricular ejection fraction < 50%).
Combination therapy with RAS-I and bepridil may be useful for maintenance of sinus rhythm.
Journal of Cardiology 12/2007; 50(6):343-50. · 1.28 Impact Factor
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Yoshiyasu Aizawa,
Wataru Mitsuma,
Taruna Ikrar,
Satoru Komura,
Haruo Hanawa,
Seiichi Miyajima, Fumito Miyoshi,
Youichi Kobayashi,
Masaomi Chinushi,
Akinori Kimura,
Masayasu Hiraoka,
Yoshifusa Aizawa
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ABSTRACT: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is characterized by adrenergic induced bidirectional or polymorphic ventricular tachycardias. Some of CPVT families were reported to be associated with cardiac ryanodine receptor gene (RyR2) mutations. However, association between RyR2 and other arrhythmogenic disorders is not clarified. In this study, we analyzed 83 Japanese patients including patients with long-QT syndrome, Brugada syndrome, idiopathic ventricular fibrillation, arrhythmogenic right ventricular cardiomyopathy and CPVT. Genetic screening of RyR2 revealed 3 distinct mutations among 4 families with CPVT (75% of incidence). However, no mutation was found in other groups. This is the first report to demonstrate prevalence of RyR2 mutations in various arrhythmogenic disorders in Japan. RyR2 mutations were detected frequently in CPVT but not in other diseases.
International journal of cardiology 04/2007; 116(2):263-5. · 7.08 Impact Factor
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Mitsuharu Kawamura,
Youichi Kobayashi,
Hiroyuki Ito,
Tatsuya Onuki, Fumito Miyoshi,
Taka-aki Matsuyama,
Norikazu Watanabe,
Shunshou Ryu,
Taku Asano,
Akira Miyata,
Kaoru Tanno,
Takashi Katagiri
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ABSTRACT: Transthoracic epicardial ablation can be an alternative to conventional treatment for critical pathways of ventricular tachycardia located in the epicardium. However, the usefulness and safety of epicardial ablation close to the coronary arteries (CA) is not clear. The purpose of the present experimental animal study was to analyze the efficacy and safety of epicardial radiofrequency (RF) ablation close to the CA.
Of the left ventricle-epicardium ablated sites, 35 lesions (20 with cooling and 15 without cooling) were close to the CA (left anterior descending artery < or = 15 mm) and 33 lesions (23 with cooling and 10 without cooling) were further from the CA. For sites close to the CA, epicardial ablation was effective in 77% (15/20) with cooling and in 40% (6/15) without cooling. There was a significant difference of effective ablation between with cooling and without cooling (p < 0.05). For cooling, epicardial lesion size could be predicted by the change of endocardial ventricular potential using a basket catheter. No damage to major epicardial arteries was detected when the catheter tip was positioned 5 mm away from the CA.
Close to the CA, RF ablation with cooling is more effective than RF without cooling and is safe if the ablation sites are located 5 mm away from the major CA.
Circulation Journal 08/2006; 70(7):926-32. · 3.77 Impact Factor
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Hiroyuki Kayano,
Hiroaki Ueda,
Tomoaki Kawamata, Fumito Miyoshi,
Tsutomu Toshida,
Norikazu Watanabe,
Yuichi Hirano,
Mitsuharu Kawamura,
Taku Asano,
Shyhaku Kou,
Kaoru Tanno,
Masaki Ozawa,
Youichi Kobayashi,
Takashi Katagiri
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ABSTRACT: The effects of cardiac resynchronization therapy (CRT) with various atrioventricular conduction delay settings were investigated on cardiac hemodynamic changes involved in coronary flow velocity using color and pulsed wave Doppler modalities and myocardial regional contractility using a novel echocardiographic technique (strain imaging).
Seven patients with advanced heart failure (left ventricular ejection fraction < 35%) and left bundle branch block(QRS > or = 140 msec) were treated with CRT. Color and pulsed wave Doppler imaging were performed from the apical four-chamber view to examine the cardiac functions such as stroke volume, cardiac output, mitral regurgitant volume and coronary flow velocity. Strain imaging was performed to quantify the asynchrony of both intraventricular and interventricular time delay between the septum and left ventricular free wall (posterior wall) and to assess the regional contractile function. Wall motion was also evaluated.
Intraventricular and interventricular asynchrony were improved from 173 +/- 18 to 60 +/- 6 msec, and 69 +/- 25 to 12 +/- 3 msec, respectively. Stroke volume (55.2 +/- 6.2 to 76.8 +/- 10.8 ml; 39% up), cardiac output (3.9 +/- 0.3 to 5.4 +/- 0.5 I/min; 38% up) and coronary flow velocity (24 +/- 3 to 36 +/- 5 cm/sec; 50% up) were greatly increased and mitral regurgitant volume (59.7 +/- 18.0 to 38.9 +/- 11.3 ml; 35% down)was clearly decreased. Septal wall shortening was greatly increased from 10.2 +/- 2.3% to 17.0 +/- 1.8% and septal wall motion (radial thickening)was also improved simultaneously. Atrioventricular interval settings influenced all above parameters.
CRT improved the cardiac hemodynamics involved in coronary flow significantly due to both resynchronization of inter and intra asynchrony, and improvement of the regional myocardial contraction in patients with severe congestive heart failure and complete left bundle branch block.
Journal of Cardiology 02/2006; 47(2):51-61. · 1.28 Impact Factor
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Fumito Miyoshi,
Youichi Kobayashi,
Hiroyuki Itou,
Tatsuya Onuki,
Takaaki Matsuyama,
Norikazu Watanabe,
Chungchang Liu,
Mitsuharu Kawamura,
Taku Asano,
Akira Miyata,
Haruyuki Nakagawa,
Kaoru Tanno,
Takao Baba,
Takashi Katagiri
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ABSTRACT: The recent studies showed that right ventricular (RV) pacing was associated with worsening of heart failure. The aim of this study is to clarify the clinical significance of paced QRS duration during RV pacing to predict congestive heart failure (CHF) patients.
This study enrolled in 92 patients with atrioventricular block who underwent initial pacemaker implantation. The paced QRS duration was automatically obtained by electrocardiography immediately after pacemaker implantation and then by routine attendance at a pacemaker clinic every 3 months. The paced QRS duration was positively correlated with left ventricular end-diastolic dimension (P < 0.05) and left ventricular end-systolic dimension (P < 0.05), and tended to negatively correlate with left ventricular ejection fraction (P = 0.0507). The paced QRS duration immediately after pacemaker implantation was 170.4 +/- 18.9 ms. During a mean follow-up period of 53 +/- 16 months, 16 patients developed CHF. We selected as a cut-off value the nearest whole number (190 ms) that was one standard deviation greater than the mean, and divided into two groups according to baseline paced QRS duration. Patients with a paced QRS duration of <190 ms comprised group A (n = 77, nine of which developed CHF) and the remainder comprised group B (n = 15, seven of which developed CHF). Prolonged paced QRS duration (> or =190 ms) was associated with a significant increase in the overall morbidity of CHF (P < 0.05). Additionally, paced QRS duration significantly prolonged during the follow-up period among group A patients with CHF (P < 0.05), but did not change among patients without CHF.
We concluded that paced QRS duration can be a useful indicator of impaired left ventricular function in patients with RV pacing. Even in patients whose paced QRS duration is relatively shorter, progressive prolongation of paced QRS duration can predict the development of CHF.
Pacing and Clinical Electrophysiology 11/2005; 28(11):1182-8. · 1.35 Impact Factor
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Journal of Cardiovascular Electrophysiology 04/2005; 16(3):354-5. · 3.06 Impact Factor
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ABSTRACT: The Multicenter Automatic Defibrillator Implantation Trial (MADIT) II investigators concluded that prophylactic use of an implantable cardioverter defibrillator (ICD) improved survival in patients with prior myocardial infarction (MI) and reduced the left ventricular ejection fraction (LVEF). However, it is unclear whether MADIT II criteria for ICD implantation are appropriate for Japanese patients.
During the period 1997 to 2001 90 (M/F: 75/15; mean age: 65+/-9 years) of the 3,258 patients who underwent elective cardiac catheterization met MADIT II criteria (Q-wave MI more than 4 weeks prior; LVEF <or=0.30; >21 years of age; electrophysiologic testing not required) and were selected in this retrospective study of patient prognosis after catheterization. During the 37+/-12-month follow-up period, 15 patients died of congestive heart failure (n=9), sudden cardiac death (n=2), acute MI (n=1), or noncardiac causes (n=3). The survival rate in the present series was comparable with that in the MADIT II defibrillator group, but higher than that in the MADIT II conventional therapy group. A significantly greater percentage of the present patients were found to be in New York Heart Association class I and have undergone percutaneous coronary intervention than in MADIT II.
These results suggest that it may be inappropriate to apply MADIT II criteria to Japanese patients.
Circulation Journal 01/2005; 69(1):19-22. · 3.77 Impact Factor
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Norikazu Watanabe,
Youichi Kobayashi,
Kaoru Tanno, Fumito Miyoshi,
Taku Asano,
Mitsuharu Kawamura,
Yoshino Mikami,
Tarou Adachi,
Syunsyou Ryu,
Akira Miyata,
Takashi Katagiri
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ABSTRACT: Myocardial transmural dispersion of repolarization (TDR) has been associated with reentrant arrhythmias in animal studies but a clinical association has not yet to been demonstrated. The present study examines the relationship between TDR and ventricular tachyarrhythmias in human subjects.
This study consisted of 65 patients with non-sustained ventricular tachycardia, sustained ventricular tachycardia, ventricular fibrillation or unexplained syncope with organic heart disease. The control group included 65 patients with paroxysmal supraventricular tachycardia. The 12 ECG was recorded at a recording rate of 100 mm/sec. The interval from the peak to the end of the T wave in the precordial (ECG), referred to as TpTe was assumed to be representative of TDR.
Patients were divided into three groups based on the ability to induce VT at the time of electrophysiologic study: VT inducible group (n=37), VT non-inducible group (n=25) and control group (n=65). V4 TpTe/ radical RR was significantly prolonged in the VT inducible group, as compared to the VT non-inducible group (n=25) and the control group (118.9 +/- 26.1 vs. 103.9 +/- 25.7, 104.1 +/- 22.6 ms, P<.05). Patients who develop VT spontaneously (n=13) during a mean follow-up period of 25 months, displayed significantly prolonged V3 TpTe/ radical RR, compared to patients who did not develop VT spontaneously or the control group (132.5 +/- 37.4 vs. 109.8 +/- 26.3, 107.1 +/- 24.1 ms, P <.05).
Prolonged TDR is associated with inducibility as well as spontaneous development of VT in higher risk patients. TDR may be a useful index for predicting ventricular tachyarrhythmias.
Journal of Electrocardiology 08/2004; 37(3):191-200. · 1.14 Impact Factor
