Read by QxMD icon Read

Early repolarization

Maarten Timmers, Vikash Sinha, Borje Darpo, Brian Smith, Randy Brown, Hongqi Xue, Georg Ferber, Johannes Streffer, Alberto Russu, Luc Tritsmans, Bhavna Solanki, Jennifer Bogert, Luc Van Nueten, Giacomo Salvadore, Partha Nandy
Nonclinical assays with JNJ-54861911, a β-secretase 1 inhibitor have indicated that at high concentrations, it may delay cardiac repolarization. A 4-way crossover thorough QT (TQT) study was performed in 64 healthy subjects with 50 and 150 mg JNJ-54861911 once daily for 7 days, placebo, and 400 mg moxifloxacin. Retrospective high-precision QT (HPQT) analysis was performed on serial elecrocardiograms extracted from first-in-human single-ascending dose (SAD) and multiple-ascending dose (MAD) studies to evaluate if early studies could detect and predict QT effect...
March 5, 2018: Journal of Clinical Pharmacology
Wenjiao Zhao, Guihua Lu, Li Liu, Zhishan Sun, Mingxin Wu, Wenyan Yi, Haiyan Chen, Yanhui Li, Lilong Tang, Jianping Zeng
BACKGROUND The aim of this study was to compare the use of the standard 12-lead electrocardiogram (ECG) with the SAN-Atrial-AVN-His (SAAH) ECG (Model PHS-A10), a new automated and integrated signals recognition system that detects micro-waveforms within the P, QRS, and T-wave, in a pig model of acute myocardial infarction (MI). MATERIAL AND METHODS Six medium-sized domestic Chinese pigs underwent general anesthesia, and an angioplasty balloon was placed and dilated for 120 minutes in the first diagonal coronary artery arising from the left anterior descending (LAD) coronary artery...
March 4, 2018: Medical Science Monitor: International Medical Journal of Experimental and Clinical Research
Murat Sucu, Berzal Ucaman, Gökhan Altunbas
BACKGROUND: The coronary slow flow phenomenon (CSFP) is well-documented, and the early repolarization pattern (ERP) has recently been shown to be a risk factor for the development of malignant ventricular arrhythmias. METHODS: Those with true CSFP were included as cases and those with normal angiograms were included as controls. We assessed J-point elevation on surface electrocardiograms (ECGs) and defined ERP as notching or slurring of the terminal portion of the QRS takeoff...
February 20, 2018: Scandinavian Cardiovascular Journal: SCJ
Tsukasa Kamakura, Mitsuru Wada, Kohei Ishibashi, Yuko Y Inoue, Koji Miyamoto, Hideo Okamura, Satoshi Nagase, Takashi Noda, Takeshi Aiba, Satoshi Yasuda, Wataru Shimizu, Shiro Kamakura, Kengo Kusano
BACKGROUND: Previously described patients with early repolarization syndrome (ERS) may have experienced silent coronary artery spasm (CAS) because the diagnosis of CAS was mainly based on symptoms or coronary angiography findings, without performing a spasm provocation test. This study investigated the significance of CAS diagnosis and evaluated the incidence of silent CAS in patients with possible ERS (ie, idiopathic ventricular fibrillation [VF] and inferolateral J wave). METHODS AND RESULTS: The study included 34 patients with idiopathic VF and inferolateral J wave...
February 7, 2018: Journal of the American Heart Association
David F Miranda, Angie S Lobo, Brooks Walsh, Yader Sandoval, Stephen W Smith
The 12-lead electrocardiogram (ECG) remains the most immediately accessible and widely used initial diagnostic tool for guiding management in patients with suspected myocardial infarction (MI). Although the development of high-sensitivity cardiac troponin assays has improved the rule-in and rule-out and risk stratification of acute MI without ST elevation, the immediate management of the subset of acute MI with acute coronary occlusion depends on integrating clinical presentation and ECG findings. Careful interpretation of the ECG might yield subtle features suggestive of ischemia that might facilitate more rapid triage of patients with subtle acute coronary occlusion or, conversely, in identification of ST-elevation MI mimics (pseudo ST-elevation MI patterns)...
February 2018: Canadian Journal of Cardiology
Ziqing Yu, Zhangwei Chen, Yuan Wu, Ruizhen Chen, Minghui Li, Xueying Chen, Shengmei Qin, Yixiu Liang, Yangang Su, Junbo Ge
BACKGROUND: Abnormal cardiac repolarization is closely associated with ventricular tachycardia/ventricular fibrillation (VT/VF). Myocardial ischemia and infarction aggravate cardiac repolarization dispersion, and VT/VF could be lethal in the early stage of ST-segment elevation myocardial infarction (STEMI). Unfortunately, VT/VF cannot be effectively predicted in current clinical practice. The present study aimed to assess electrocardiographic parameters of the sinus rhythmic complex in relation to cardiac repolarization, e...
February 5, 2018: Journal of Cardiovascular Electrophysiology
Hao Yao, Cheng-Cheng Ji, Yun-Jiu Cheng, Xu-Miao Chen, Li-Juan Liu, Jun Fan, Su-Hua Wu
BACKGROUND: Recent studies have revealed that mutation in KCNE1, β-subunits of cardiac potassium channel, involved in ventricular fibrillation. Whereas its role in early repolarization syndrome (ERS) is less well understood. OBJECTIVE: To study whether mutant in KCNE1 is associated with ERS and explore the possible underlying molecular mechanisms. METHODS: Whole genome from four unrelated families with ERS was amplified and sequenced. Wild-type (WT) KCNE1 and/or KCNE1-S38G (S38G) were expressed in HEK293 cells with KCNQ1...
January 29, 2018: Experimental Cell Research
Shigehiro Karashima, Toyonobu Tsuda, Yusuke Wakabayashi, Mitsuhiro Kometani, Masashi Demura, Taro Ichise, Masa-Aki Kawashiri, Yoshiyu Takeda, Kenshi Hayashi, Takashi Yoneda
A J wave is a common electrocardiographic finding in the general population. Individuals with prominent J waves in multiple electrocardiogram (ECG) leads have a higher risk of lethal arrhythmias than those with low-amplitude J waves. There are few reports about the relationship between thyroid function and J-wave amplitude. We report the case of a 45-year-old man who had unexpected ventricular fibrillation (VF). He had dynamic J-point elevation in multiple ECG leads. Possible early repolarization syndrome was diagnosed...
February 1, 2018: Journal of the Endocrine Society
Heidi L Lujan, Joshua P Rivers, Stephen E DiCarlo
Early pioneering investigators discovered, in anesthetized dogs, a protective period within the cardiac cycle. The protective period was a time within the cardiac cycle when a precisely timed stimulus prevented the initiation of ventricular fibrillation caused by an earlier stimulus. Thus, in addition to the susceptible period of repolarization discussed by Wiggers and Wegria (Am. J. Physiol. 131:296, 1940; Am. J. Physiol. 128:500, 1940), there is also a nearby protective period. This report describes a protective period within the cardiac cycle of conscious mice when a precisely timed stimulus prevented the initiation of ventricular tachycardia caused by an earlier stimulus...
January 2018: Physiological Reports
Sergio Lainez, Adélaïde Doray, Jules C Hancox, Mark B Cannell
Transient outward potassium current (Ito) contributes to early repolarization of many mammalian cardiac action potentials, including human, whilst the rapid delayed rectifier K+ current (IKr) contributes to later repolarization. Fast Ito channels can be produced from the Shal family KCNDE gene product Kv4.3s, although accessory subunits including KChIP2.x and DPP6 are also needed to produce a near physiological Ito. In this study, the effect of KChIP2.1 & KChIP2.2 (also known as KChIP2b and KChIP2c respectively), alone or in conjunction with the accessory subunit DPP6, on both Kv4...
January 26, 2018: Biochemical Pharmacology
Valentine Sergeev, Frances Perry, Thomas M Roston, Shubhayan Sanatani, Glen F Tibbits, Thomas W Claydon
Long QT syndrome (LQTS) is the most common cardiac ion channelopathy and has been found to be responsible for approximately 10% of sudden infant death syndrome (SIDS) cases. Despite increasing use of broad panels and now whole exome sequencing (WES) in the investigation of SIDS, the probability of identifying a pathogenic mutation in a SIDS victim is low. We report a family-based study who are afflicted by recurrent SIDS in which several members harbor a variant, p.Pro963Thr, in the C-terminal region of the human-ether-a-go-go (hERG) gene, published to be responsible for cases of LQTS type 2...
December 20, 2017: Forensic Science International
Gerrit Frommeyer, Julius Krawczyk, Christian Ellermann, Nils Bögeholz, Simon Kochhäuser, Dirk G Dechering, Michael Fehr, Lars Eckardt
AIMS: A significant antiarrhythmic potential of ryanodine receptor inhibition was reported in experimental studies. The aim of the present study was to assess potential antiarrhythmic effects of dantrolene in an experimental whole-heart model of drug-induced long-QT syndrome (LQTS). METHODS: In 12 isolated rabbit hearts long-QT-2-syndrome was simulated by infusion of erythromycin (300μM). 12 rabbit hearts were treated with veratridine (0.5μM) to mimic long-QT-3-syndrome...
January 4, 2018: Journal of Cardiovascular Electrophysiology
Mohsen Sharifi, Dan Buzatu, Stephen Harris, Jon Wilkes
BACKGROUND: Blockage of some ion channels and in particular, the hERG (human Ether-a'-go-go-Related Gene) cardiac potassium channel delays cardiac repolarization and can induce arrhythmia. In some cases it leads to a potentially life-threatening arrhythmia known as Torsade de Pointes (TdP). Therefore recognizing drugs with TdP risk is essential. Candidate drugs that are determined not to cause cardiac ion channel blockage are more likely to pass successfully through clinical phases II and III trials (and preclinical work) and not be withdrawn even later from the marketplace due to cardiotoxic effects...
December 28, 2017: BMC Bioinformatics
Samuel Chauveau, Alexandre Janin, Marianne Till, Elodie Morel, Philippe Chevalier, Gilles Millat
No abstract text is available yet for this article.
December 2017: HeartRhythm Case Reports
Nirmeen A Kishk, Yasser Sharaf, Asmaa M Ebraheim, Yasser Baghdady, Nelly Alieldin, Ahmed Afify, Ahmed Eldamaty
BACKGROUND AND OBJECTIVE: The occurrence of cardiac electrical abnormalities such as repolarization disorders in patients with epilepsy was previously documented and may, in part, clarify the mechanism of sudden unexpected death in those patients. The aim of this study was to investigate the frequency of cardiac repolarization disorders among patients with epilepsy and whether specific demographic- or disease-related features were associated with their occurrence. SUBJECTS AND METHODS: This cross-sectional study was carried out on 1000 subjects with epilepsy who were compared with age- and sex-matched 2500 subjects without epilepsy...
December 20, 2017: Epilepsy & Behavior: E&B
Elias B Hanna, Paul A LeLorier, David M Tadin, Ronnie O Ortiz, D Luke Glancy
A 27-year-old man presents with successfully resuscitated ventricular fibrillation. Structural and electrical causes of ventricular fibrillation in the young are presented along with a diagnostic strategy. Electrocardiographic features of malignant early repolarization are discussed.
February 15, 2018: American Journal of Cardiology
Pedro Silva Cunha
No abstract text is available yet for this article.
December 2017: Portuguese Journal of Cardiology: An Official Journal of the Portuguese Society of Cardiology
Hacı Ahmet Kasapkara, Ayşegül Şentürk, Emine Bilen, Hüseyin Ayhan, Bilge Duran Karaduman, Zeynep Şeyma Turinay, Murat Can Güney, Tahir Durmaz, Telat Keleş, Engin Bozkurt
INTRODUCTION AND AIM: Sarcoidosis increases inhomogeneity in ventricular repolarization due to the presence of sarcoid granuloma, which significantly correlates with ventricular fibrillation. Various studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (T-peak to T-end [Tpe] interval) may correspond to the transmural dispersion of repolarization and that increased Tpe interval and Tpe/QT ratio are associated with malignant ventricular arrhythmias...
December 2017: Portuguese Journal of Cardiology: An Official Journal of the Portuguese Society of Cardiology
Enid Van Nieuwenhuyse, Gunnar Seemann, Alexander V Panfilov, Nele Vandersickel
Early Afterdepolarizations, EADs, are defined as the reversal of the action potential before completion of the repolarization phase, which can result in ectopic beats. However, the series of mechanisms of EADs leading to these ectopic beats and related cardiac arrhythmias are not well understood. Therefore, we aimed to investigate the influence of this single cell behavior on the whole heart level. For this study we used a modified version of the Ten Tusscher-Panfilov model of human ventricular cells (TP06) which we implemented in a 3D ventricle model including realistic fiber orientations...
2017: PloS One
Sofia Chatzidou, Evangelos Repasos, Sotiris Plastiras, Christos Kontogiannis, Marinos Kosmopoulos, Diamantis I Tsilimigras, Ioannis Paraskevaidis, Stelios Rokas
Early repolarization syndrome (ERS) was originally considered a normal variant with benign outcome. However, recent studies have demonstrated that it can be linked to a considerable risk of life-threatening arrhythmias and sudden cardiac death. We report a case with an extraordinary, extremely malignant clinical expression of ERS refractory to all antiarrhythmic drugs including quinidine. This case demonstrates real-time changes of dynamic electrocardiogram (ECG) preceding a polymorphic ventricular tachycardia (VT)-ventricular fibrillation (VF) and possible external factors triggering arrhythmia onset...
December 5, 2017: Annals of Noninvasive Electrocardiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"