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https://www.readbyqxmd.com/read/29922124/association-between-depression-anxiety-and-antidepressant-use-with-t-wave-amplitude-and-qt-interval
#1
Mandy X Hu, Femke Lamers, Brenda W J H Penninx, Eco J C de Geus
Objectives: Cardiac repolarization may be affected by psychiatric disorders and/or antidepressant use, but evidence for this is inconclusive. This study examined the relationship between depressive and anxiety disorder and use of antidepressants with T-wave amplitude (TWA) and QT-interval. Methods: Data was obtained from the Netherlands Study of Depression and Anxiety ( n = 1,383). Depression/anxiety was diagnosed with the DSM-IV based Composite International Diagnostic Interview. The use of tricyclic antidepressants (TCAs), selective serotonin and noradrenalin reuptake inhibitors (SNRIs), and selective serotonin reuptake inhibitors (SSRIs) was established...
2018: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/29922026/t-wave-alternans-in-long-qt-syndrome
#2
Siddharth Narayan Gadage
Long QT syndrome (LQTS) is a congenital disorder characterized by prolongation of QT interval in the electrocardiogram (ECG) and a propensity to develop ventricular arrhythmias, which may lead to syncope, cardiac arrest or sudden death. T-wave alternans (TWA), a phenomenon of beat-to-beat variability in the repolarization phase of the ventricles, has been closely associated with an increased risk of ventricular tachyarrhythmic events (VTE) and sudden cardiac death (SCD).
May 2018: Annals of Pediatric Cardiology
https://www.readbyqxmd.com/read/29920724/afterdepolarizations-and-triggered-activity-as-a-mechanism-for-clinical-arrhythmias
#3
REVIEW
Andrew L Wit
Afterdepolarizations cause triggered arrhythmias. One kind occurs after repolarization is complete, delayed afterdepolarizations (DADs). Another occurs as an interruption in repolarization, early afterdepolarizations (EADs). Afterdepolarizations initiate arrhythmias when they depolarize membrane potential to threshold potential for triggering action potentials. DADs usually occur mostly when Ca2+ in the sarcoplasmic reticulum (SR) is elevated. The SR leaks some of the Ca2+ into the myoplasm through Ca2+ release channels controlled by ryanodine receptors (RyR2) during diastole...
June 19, 2018: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/29908369/repolarization-heterogeneity-in-patients-with-cardiac-resynchronization-therapy-and-its-relation-to-ventricular-tachyarrhythmias
#4
Marta Cvijić, Bor Antolič, Luka Klemen, Igor Zupan
BACKGROUND: s: Cardiac resynchronization therapy (CRT) has shown to induce left ventricular reverse remodelling, but little is known about its influence on ventricular repolarization. OBJECTIVE: The aim of our study was to evaluate changes of ventricular repolarization of native conduction after CRT and its relation to ventricular tachycardia (VT) and ventricular fibrillation (VF) during long-term follow-up. METHODS: We prospectively included 64 patients with heart failure treated with CRT...
June 13, 2018: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/29908347/aging-related-functional-and-structural-changes-in-the-heart-and-aorta-mitotempo-improves-aged-cardiovascular-performance
#5
Yusuf Olgar, Sinan Degirmenci, Aysegul Durak, Deniz Billur, Belgin Can, Gizem Kayki Mutlu, Ebru Arioglu Inan, Belma Turan
Aging in humans represents declining in cardio-protective systems, however its mechanisms are not known yet. We aimed to analyse how aging affects key mechanisms responsible for contractile dysfunction via comparing the improperly synchrony between electrical and mechanical activities in male aged-rats (24-month old) comparison to those of adult-rats (6-month old). We determined significantly increased systemic oxidative stress with decreased antioxidant capacity, clear insulin resistance and hypertrophy in aged-rats with normal fasting blood glucose...
June 13, 2018: Experimental Gerontology
https://www.readbyqxmd.com/read/29907430/improving-estimates-of-groundwater-velocity-in-a-fractured-rock-borehole-using-hydraulic-and-tracer-dilution-methods
#6
Carlos H Maldaner, Patrick M Quinn, John A Cherry, Beth L Parker
A straddle-packer system for use in boreholes in fractured rock was modified to investigate the average linear groundwater velocity (v¯f ) in fractures under ambient flow conditions. This packer system allows two different tests to be conducted in the same interval between packers without redeploying the system: (1) forced gradient hydraulic tests to determine the interval transmissivity (T), and (2) borehole dilution experiments to determine the groundwater flow rate (Qt ) across the test interval. The constant head step test method provides assurance that flow is Darcian when determining T for each interval and identifies the flow rate at the onset of non-Darcian flow...
May 17, 2018: Journal of Contaminant Hydrology
https://www.readbyqxmd.com/read/29904445/malignant-ventricular-arrhythmias-resulting-from-drug-induced-qtc-prolongation-a-retrospective-study
#7
Renato De Vecchis, Carmelina Ariano, Giuseppina Di Biase, Michel Noutsias
Background: Several drug classes (antiarrhythmics, antimicrobials, antidepressants, phenothiazines, opiates, prokinetics of digestive tract, etc.) have been related to ventricular hyperkinetic arrhythmias such as torsade de pointes (TdP). TdPs are usually heralded by an abnormal prolongation of heart rate-corrected QT interval on the electrocardiogram, so-called drug-induced long heart rate-corrected QT (diLQTc). We don't know to what extent the drug-induced QTc prolongation is able to predict malignant arrhythmias...
July 2018: Journal of Clinical Medicine Research
https://www.readbyqxmd.com/read/29898892/mitochondrial-ros-drive-sudden-cardiac-death-and-chronic-proteome-remodeling-in-heart-failure
#8
Swati Dey, Deeptankar DeMazumder, Agnieszka Sidor, D B Foster, Brian O'Rourke
<u>Rationale:</u> Despite increasing prevalence and incidence of heart failure (HF), therapeutic options remain limited. In early stages of HF, sudden cardiac death (SCD) from ventricular arrhythmias claims many lives. Reactive oxygen species (ROS) have been implicated in both arrhythmias and contractile dysfunction. However, little is known about how ROS in specific subcellular compartments contribute to HF or SCD pathophysiology. The role of ROS in chronic proteome remodeling has not been explored...
June 13, 2018: Circulation Research
https://www.readbyqxmd.com/read/29898835/comparison-of-automated-interval-measurements-by-widely-used-algorithms-in-digital-electrocardiographs
#9
Paul Kligfield, Fabio Badilini, Isabelle Denjoy, Saeed Babaeizadeh, Elaine Clark, Johan De Bie, Brian Devine, Fabrice Extramiana, Gianluca Generali, Richard Gregg, Eric Helfenbein, Jan Kors, Remo Leber, Peter Macfarlane, Pierre Maison-Blanche, Ian Rowlandson, Ramun Schmid, Martino Vaglio, Gerard van Herpen, Joel Xue, Brian Young, Cynthia L Green
BACKGROUND: Automated measurements of electrocardiographic (ECG) intervals by current-generation digital electrocardiographs are critical to computer-based ECG diagnostic statements, to serial comparison of ECGs, and to epidemiological studies of ECG findings in populations. A previous study demonstrated generally small but often significant systematic differences among 4 algorithms widely used for automated ECG in the United States and that measurement differences could be related to the degree of abnormality of the underlying tracing...
June 2018: American Heart Journal
https://www.readbyqxmd.com/read/29898699/rapid-calcium-loss-may-cause-arrhythmia-in-hemofiltration-with-regional-citrate-anticoagulation-a-case-report
#10
Buyun Wu, Jing Wang, Guang Yang, Changying Xing, Huijuan Mao
BACKGROUND: Renal replacement therapy (RRT) with regional citrate anticoagulation (RCA) is an important therapeutic approach for refractory hypercalcemia complicated with renal failure. However, RCA has the potential to induce arrhythmia caused by rapid calcium loss. We report a case of arrhythmia associated with rapid calcium loss during RCA-RRT. CASE PRESENTATION: A 51-year-old man with hypercalcemia, primary hyperparathyroidism, and acute kidney injury was treated by predilutional-RCA-hemofiltration at a rate of 4...
June 14, 2018: BMC Nephrology
https://www.readbyqxmd.com/read/29898002/qtc-interval-prolongation-in-critically-ill-patients-prevalence-risk-factors-and-associated-medications
#11
Flávia Medeiros Fernandes, Eliane Pereira Silva, Rand Randall Martins, Antonio Gouveia Oliveira
PURPOSE: To investigate the prevalence and risk factors of acquired long QT syndrome (LQTS) on admission to a general Intensive Care Unit (ICU), and to assess the risk of LQTS associated with prescribed medications. METHODS: Prospective observational, cross-sectional study approved by the Institutional Review Board. Between May 2014 and July 2016, 412 patients >18 years-old consecutively admitted to the ICU of a university hospital were included. LQTS was defined as a QT interval on the admission electrocardiogram corrected using Bazett's formula (QTc) >460 ms for men and >470 ms for women...
2018: PloS One
https://www.readbyqxmd.com/read/29894447/corrected-qt-interval-prolongation-in-hospitalized-pediatric-patients-receiving-methadone
#12
Amy J Schwinghammer, Machelle D Wilson, Brent A Hall
OBJECTIVES: Methadone is often used in pediatric patients to prevent or treat opioid withdrawal after prolonged sedation. Prolonged corrected QT interval is an important adverse effect of methadone because it can progress to torsades de pointes, a potentially fatal dysrhythmia. The prevalence of corrected QT interval prolongation and contributing risk factors are not well defined in hospitalized pediatric patients receiving methadone. The study purpose was to identify the frequency and risk factors of corrected QT interval prolongation in hospitalized pediatric patients receiving methadone...
June 11, 2018: Pediatric Critical Care Medicine
https://www.readbyqxmd.com/read/29887480/a-wearable-remote-monitoring-system-for-the-identification-of-subjects-with-a-prolonged-qt-interval-or-at-risk-for-drug-induced-long-qt-syndrome
#13
Silvia Castelletti, Federica Dagradi, Karine Goulene, Aurora I Danza, Enrico Baldi, Marco Stramba-Badiale, Peter J Schwartz
BACKGROUND: A correct measurement of the QT interval in the out-of-hospital setting is important whenever the long QT syndrome (LQTS) is suspected or a therapy might lead to drug-induced LQTS (diLQTS) because QT interval monitoring in the initial days of therapy could alert to dangerous QT prolongation. We explored whether automated QTc measurements (BGM) by BodyGuardian™ (BG), a wearable remote monitoring system, are sufficiently reliable compared to our own manual measurements (MM) performed on the same beats during 12‑lead Holter recordings in LQTS patients (pts) and in healthy controls...
September 1, 2018: International Journal of Cardiology
https://www.readbyqxmd.com/read/29887371/risk-of-sudden-unexplained-death-after-use-of-dihydroartemisinin-piperaquine-for-malaria-a-systematic-review-and-bayesian-meta-analysis
#14
Xin Hui S Chan, Yan Naung Win, Laura J Mawer, Jireh Y Tan, Josep Brugada, Nicholas J White
BACKGROUND: Dihydroartemisinin-piperaquine is an effective and well tolerated artemisinin-based combination therapy that has been assessed extensively for the prevention and treatment of malaria. Piperaquine, similar to several structurally related antimalarials currently used, can prolong cardiac ventricular repolarisation duration and the electrocardiographic QT interval, leading to concerns about its proarrhythmic potential. We aimed to assess the risk of potentially lethal iatrogenic ventricular arrhythmias in individuals receiving dihydroartemisinin-piperaquine...
June 7, 2018: Lancet Infectious Diseases
https://www.readbyqxmd.com/read/29887217/addition-of-digoxin-improves-cardiac-function-in-children-with-the-dilated-cardiomyopathy-with-ataxia-syndrome-a-mitochondrial-cardiomyopathy
#15
Steven C Greenway, Frederic Dallaire, Hassan Hazari, Dhwani Patel, Aneal Khan
BACKGROUND: The dilated cardiomyopathy with ataxia syndrome (DCMA) is a rare mitochondrial disorder characterized by progressive cardiomyopathy, prolonged QT interval and early death in childhood related to intractable heart failure. We present a case series of 9 children with DCMA who demonstrated functional improvement and favourable left ventricular remodeling only after digoxin was added to their medical therapy. METHODS: A retrospective review of 46 patients with DCMA followed at the Alberta Children's Hospital from 2005 to 2017 identified 9 patients who were treated with digoxin and had serial echocardiography data...
March 1, 2018: Canadian Journal of Cardiology
https://www.readbyqxmd.com/read/29886153/findings-relevant-to-the-qrs-wave-in-the-resting-electrocardiogram-are-associated-with-circulating-concentrations-of-high-sensitivity-cardiac-troponin-i-in-the-general-population
#16
Tomonori Sugiura, Yasuaki Dohi, Hiroyuki Takase, Satoshi Fujii, Nobuyuki Ohte
Myocardial damage could develop asymptomatically through nonischemic mechanisms such as cardiac overload. This study investigated possible associations between electrocardiogram (ECG) findings relevant to the QRS wave and high-sensitivity cardiac troponin I (hs-cTnI) in the general population. Subjects undergoing their annual health checkup were enrolled in the study (n = 1258). ECG features relevant to the QRS wave that were investigated included PQ interval, QRS voltage (Sokolow-Lyon voltage), QRS duration, product of QRS duration and voltage (Cornell product), corrected QT interval, and QRS axis...
May 18, 2018: Journal of the American Society of Hypertension: JASH
https://www.readbyqxmd.com/read/29882591/predictive-analytics-for-identification-of-patients-at-risk-for-qt-interval-prolongation-a-systematic-review
#17
Elena Tomaselli Muensterman, James E Tisdale
Prolongation of the heart rate-corrected QT (QTc) interval increases the risk for torsades de pointes (TdP), a potentially fatal arrhythmia. The likelihood of TdP is higher in patients with risk factors, which include female sex, older age, heart failure with reduced ejection fraction, hypokalemia, hypomagnesemia, concomitant administration of ≥ 2 QTc interval-prolonging medications, among others. Assessment and quantification of risk factors may facilitate prediction of patients at highest risk for developing QTc interval prolongation and TdP...
June 8, 2018: Pharmacotherapy
https://www.readbyqxmd.com/read/29881800/myocardial-remodeling-and-susceptibility-to-ventricular-tachycardia-in-a-model-of-chronic-epilepsy
#18
Yi-Chen Lai, Na Li, William Lawrence, Sufen Wang, Amber Levine, Daniela M Burchhardt, Robia G Pautler, Miguel Valderrábano, Xander H Wehrens, Anne E Anderson
Objective: Sympathetic predominance and ventricular repolarization abnormalities represent epilepsy-associated cardiac alterations and may underlie seizure-induced ventricular arrhythmias. Myocardial ion channel and electrical remodeling have been described early in epilepsy development and may contribute to ventricular repolarization abnormalities and excitability. Using the pilocarpine-induced acquired epilepsy model we sought to examine whether altered myocardial ion channel levels and electrophysiological changes also occur in animals with long-standing epilepsy...
June 2018: Epilepsia Open
https://www.readbyqxmd.com/read/29879475/challenges-in-implementing-and-obtaining-acceptance-for-j-tpeak-assessment-as-the-clinical-component-of-cipa
#19
Borje Darpo, Jean-Philippe Couderc
INTRODUCTION: This paper is based on a presentation held at the Annual Safety Pharmacology Society meeting in September 2017, at which challenges for the clinical component of CiPA were presented. FDA has published an automated algorithm for measurement of the J-Tpeak interval on a median beat from a vector magnitude lead derived from a 12-lead ECG. CiPA proposes that J-Tpeak prolongation < 10 ms can be used for drugs with a QTc effect < 20 ms to differentiate between safe and unsafe delayed repolarization and to reduce the level of ECG monitoring in late stage clinical trials...
June 4, 2018: Journal of Pharmacological and Toxicological Methods
https://www.readbyqxmd.com/read/29876021/anticancer-drugs-related-qtc-prolongation-torsade-de-pointes-and-sudden-death-current-evidence-and-future-research-perspectives
#20
REVIEW
Jialin Duan, Jingwen Tao, Maocai Zhai, Chengpeng Li, Ning Zhou, Jiagao Lv, Lin Wang, Li Lin, Rong Bai
Anticancer drugs may have proarrhythmic effects including drug-induced QT interval prolongation, which is of particular importance because it can lead to a fatal polymorphic ventricular tachycardia termed torsade de pointes (TdP). QT interval prolongation and TdP are rare life-threatening untoward effects of anticancer therapy, particularly with arsenic trioxides and anthracyclines, and even some novel molecular targeted drugs touted as 'tumor specific'. Several factors that affect myocardial repolarization can further increase the risk of TdP...
May 22, 2018: Oncotarget
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