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Ahmed Karim Talib,
Nobuyuki Sato,
Akira Asanome, Takuya Myojo,
Takeshi Nishiura,
Masaru Yamaki,
Naoki Nakagawa,
Naka Sakamoto,
Hisanobu Ota,
Yasuko Tanabe,
Toshiharu Takeuchi,
Yuichiro Kawamura,
Naoyuki Hasebe
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ABSTRACT: INTRODUCTION: Almost all current investigations on early repolarization syndrome (ERS) have focused on the J-wave characteristics and ST-segment configuration; however, few have reported on ventricular repolarization indexes in ERS. METHODS AND RESULTS: A total of 145 subjects were enrolled: 10 ERS patients, 45 uneventful ER pattern (ERP) subjects, and 90 healthy controls without J waves or ST-segment elevation. Ambulatory ECG-derived parameters (QT, QTc(B), QTc(F), T peak-Tend(Tpe), and QT/RR slope) were measured and statistically compared. Among the groups, there was no significant difference in the average QT and QTc(B); however, ERS patients had the shortest QTc(F) and longest Tpe (QTc(F): 396.2 ± 19 vs 410.4 ± 20 vs 419.2 ± 19 milliseconds, P = 0.036, Tpe: 84.9 ± 12 vs 70.4 ± 11 vs 66.9 ± 15 milliseconds, P < 0.001, for the ERS, ERP, and control groups, respectively). Importantly, the 24-hour QT/RR slope was significantly smaller in the ERS than ERP and control groups (QT/RR: 0.105 ± 0.01 vs 0.154 ± 0.02 vs 0.161 ± 0.03, respectively; P < 0.001). When analyzing the diurnal and nocturnal QT/RR slopes, ERS patients had small diurnal and nocturnal QT/RR slopes while the ERP and control groups had large diurnal and small nocturnal QT/RR slopes (diurnal QT/RR: 0. 077 ± 0.01 vs 0.132 ± 0.03 vs 0.143 ± 0.03, P < 0.001; nocturnal QT/RR: 0.093 ± 0.02 vs 0.129 ± 0.03 vs 0.130 ± 0.04, P = 0.02 in the ERS, ERP, and control groups, respectively). CONCLUSION: ERS patients had a continuously depressed diurnal and nocturnal adaptation of the QT interval to the heart rate. Such abnormal repolarization dynamics might provide a substrate for reentry and be an important element for developing ventricular fibrillation in the ERS cohort.
Journal of Cardiovascular Electrophysiology 12/2012; · 3.06 Impact Factor
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Takuya Myojo,
Nobuyuki Sato,
Asami Nimura,
Aya Matsuo,
Osamu Taniguchi,
Hideki Nakamura,
Ahmed Karim Talib,
Naka Sakamoto,
Toshiharu Takeuchi,
Yuichiro Kawamura,
Naoyuki Hasebe
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ABSTRACT: We describe a case of early repolarization syndrome in which augmented J waves were documented during an electrical storm associated with hypokalemia. The patient was referred to our hospital for therapy to treat recurrent ventricular fibrillation (VF). The 12-lead electrocardiogram showed giant J waves associated with hypokalemia during multiple episodes of VF. Although antiarrhythmic agents or deep sedation were not effective for the VF, an intravenous supplementation of potassium completely suppressed the VF with a reduction in the J-wave amplitude. Our report discusses the possible relationship between hypokalemia and VF in early repolarization syndrome.
Pacing and Clinical Electrophysiology 06/2012; 35(8):e234-8. · 1.35 Impact Factor
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ABSTRACT: We describe a case of a myocardial infarction, in which prominent ischemic J waves were documented during recurrent ventricular fibrillation attacks. The patient was referred to our hospital to treat an out-of hospital cardiac arrest. Although the 12-lead electrocardiogram obtained just after the first cardioversion did not show any apparent J waves, a J wave-like steep downsloping type ST-segment elevation associated with q waves in the inferior leads was documented during multiple episodes of ventricular fibrillation. Our report revealed the appearance of J waves as an important marker for lethal arrhythmias in acute ischemia.
Pacing and Clinical Electrophysiology 01/2012; 35(1):e27-30. · 1.35 Impact Factor
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Masaru Yamaki,
Nobuyuki Sato, Takuya Myojo,
Takeshi Nishiura,
Masato Nishimura,
Hideki Nakamura,
Motoi Okada,
Satoshi Fujita,
Kazutomo Go,
Naka Sakamoto,
Yasuko Tanabe,
Toshiharu Takeuchi,
Yuichiro Kawamura,
Naoyuki Hasebe
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ABSTRACT: Recent evidence suggests an association between vasospastic angina and Brugada syndrome. Here we present two cases of coronary artery disease who presented with ECG abnormalities which might have been provoked or enhanced by ischemia of the conus branch of the right coronary artery. The 12-lead ECGs demonstrated normal sinus rhythm in these two cases. Interestingly, a saddle back or coved type ST segment elevation in leads V1-V3 was documented either in the percutaneous transluminal angioplasty procedure of the proximal right coronary artery or with an intracoronary acetylcholine (Ach) administration into the right coronary artery. These Brugada type ECG changes were restored to the baseline ECG waveform after improvement in the ischemia. In the second case, vasospasms of the conus branch of the right coronary artery were associated with a coved type ST segment elevation in leads V1 to V2. We discuss the possible interaction between ischemia caused by conus branch lesions and Brugada type electrocardiographic changes.
International Heart Journal 01/2010; 51(1):68-71. · 1.16 Impact Factor
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ABSTRACT: A 47-year-old man was admitted to our hospital complaining of chest pain at rest in the early morning. Electrocardiography showed ST segment elevation in leads II, III and aVF. Emergency coronary angiography revealed total occlusion of the right coronary artery at the proximal portion. Intracoronary administration of isosorbide dinitrate successfully recanalized the right coronary artery. However, there was a thrombus image at the culprit lesion. Intracoronary administration of urokinase caused the residual thrombus to disappear completely. Follow-up coronary angiography at 1 week and 3 months revealed no organic stenotic lesion. Intravascular ultrasound showed only a little plaque without signs of ruptured plaque in the right coronary artery. Provocation coronary angiography revealed remarkable spasm causing total occlusion at the proximal portion of the right coronary artery. This case suggests that only severe coronary spasm without plaque rupture could form a thrombus causing acute coronary syndrome.
Journal of Cardiology 10/2007; 50(3):205-12. · 1.28 Impact Factor
