Read by QxMD icon Read

Cardiac memory (t-wave memory)

Dechun Yin, Mu Chen, Na Yang, Adonis Z Wu, Dongzhu Xu, Wei-Chung Tsai, Yuan Yuan, Zhipeng Tian, Yi-Hsin Chan, Changyu Shen, Zhenhui Chen, Shien-Fong Lin, James N Weiss, Peng-Sheng Chen, Thomas H Everett
BACKGROUND: Apamin-sensitive small conductance calcium-activated K current (IKAS ) is up-regulated during ventricular pacing and masks short-term cardiac memory (CM). OBJECTIVE: The purpose of this study was to determine the role of IKAS in long-term CM. METHODS: CM was created with 3-5 weeks of ventricular pacing and defined by a flat or inverted T wave off pacing. Epicardial optical mapping was performed in both paced and normal ventricles...
January 8, 2018: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Asaf Danon, Mohammed Shurrab
We describe a case of a 70year-old woman with effort dyspnea and alternating trifascicular conduction pattern, worsened with exercise to atrioventricular block (AV Block). The alternating conduction at rest resulted in marked T wave changes. We discuss the mechanism of T wave memory changes and the management of exercise-induced AV Block.
July 12, 2017: Journal of Electrocardiology
Daniel F Ortega, Luis D Barja, Emilio Logarzo, Nicolas Mangani, Analia Paolucci, Maria P Bonomini
Aims: His bundle pacing has shown to prevent detrimental effects from right ventricular apical pacing (RVA) and proved to resynchronize many conduction disturbances cases. However, the extent of His bundle pacing resynchronization is limited. An optimized stimulation waveform could expand this limit when implemented in His bundle pacing sets. In this work, we temporarily implemented RVA and Non-selective His bundle pacing with a biphasic anodal-first waveform (AF-nHB) and compared their effects against sinus rhythm (SR)...
May 17, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Irene di Matteo, Pasquale Crea
The ECG diagnosis of myocardial infarction and ischemia in pacemaker patients is often challenging. The three criteria, proposed by Sgarbossa et al. in 1996, useful to suspect myocardial ischaemia in patient with left bundle branch block were demonstrated to be valid also in pacemaker patients. In the last years, concordant negative T waves in patients with ventricular paced rhythm were linked to various expressions of acute myocardial injury. If available, comparison with previous ECG is crucial. Partial persistence of cardiac memory during fusion beats created an anomalous concordance between negative T waves and QRS axis and could induce erroneous suspicions...
July 2017: Journal of Electrocardiology
Matthias Hoyme, Ralf Surber, P Christian Schulze, Dirk Prochnau
We report the case of a 82-year-old woman who was admitted to our institution with acute chest pain, nausea, and vomiting. Because of atrial fibrillation with intermittent bradycardia, a single-chamber pacemaker was implanted 4 years ago. The initial 12-lead ECG showed atrial fibrillation with a heart rate of 70 bpm, narrow QRS, and T‑wave inversions in the inferolateral leads. Coronary artery disease was excluded by immediate cardiac catheterization. A subsequent ECG three hours later showed a ventricular paced rhythm...
March 2017: Herzschrittmachertherapie & Elektrophysiologie
Ludovico Lazzari, Federica DI Meo, Alessandra Crocetti, Michele Castelli, Chiara Marini, Stefano Donzelli, Daniella Bovelli, Giovanni Carreras, Enrico Boschetti
No abstract text is available yet for this article.
February 2017: Minerva Cardioangiologica
Takashi Nakagawa, Tetsuo Yagi, Akihiko Ishida, Yoshiaki Mibiki, Yoshihiro Yamashina, Hirokazu Sato, Eiji Sato, Juri Komatsu, Yoshifumi Saijo
BACKGROUND: Cardiac memory (CM) after idiopathic left ventricular tachycardia (ILVT) mimics ischemic T wave inversion (TWI) induced by acute coronary syndrome (ACS). We aimed to establish electrocardiography criteria for differentiating the CM from ischemic TWI. METHODS AND RESULTS: We evaluated 16 ILVT and 48 ACS patients. We identified TWI after ILVT in 9/16 patients (CM group), typically in leads II, III, aVF, aVR, and V4-6. The characteristics of CM were similar to TWI induced by ACS involving right coronary artery, but the CM group had more TWI in V4 and shorter QTc...
July 2016: Journal of Electrocardiology
Jonathan W Waks, Daniel A Steinhaus, Alexei Shvilkin, Daniel B Kramer
No abstract text is available yet for this article.
February 2016: American Journal of Medicine
Shams Y-Hassan
Reversible electrocardiographic (ECG) repolarization changes including T-wave inversions (TWI), large upright peaked T-waves (LUPTW) and prolongation of the corrected QT interval (P-QTc) have been reported in association with myriads of acute cardiac and non-cardiac diseases. Through the last 70 years, the TWIs have been described under different terms as; cerebral, giant, global, canyon, Wellens or coronary and cardiac memory T waves. During the last 15 years, the reversible TWI and LUPTW in association with P-QTc have been described as characteristic ECG features in takotsubo syndrome (TS), which also may be triggered by the same aforementioned acute cardiac and non-cardiac disease entities...
July 15, 2015: International Journal of Cardiology
Melissa A Kershaw, Felix J Rogers
CONTEXT: The electrocardiographic (ECG) pattern of high-grade stenosis of the left anterior descending coronary artery (LAD) is important clinically because of the high risk of myocardial infarction and cardiac death if the pattern is not recognized. Although the recognition of this pattern is currently widespread, false-positive ECG changes that mimic this pattern are infrequently reported. OBJECTIVE: To demonstrate that ECG changes from intermittent left bundle branch block (LBBB) and cardiac memory can mimic anterior ischemia...
November 2014: Journal of the American Osteopathic Association
Laszlo Littmann, Patrick A Proctor, Priscilla M Givens
An 83-year-old woman with chronic left bundle branch block and remote history of pacemaker implantation for intermittent AV block was hospitalized for fatigue and leg swelling. She had no cardiac complaints. Routine 12-lead electrocardiogram showed sinus rhythm with left bundle branch block. There were diffuse negative T waves in the inferior and anterolateral leads that were concordant with the QRS complexes. Echocardiogram was normal and nuclear perfusion heart scan showed no abnormality. It was noted that the negative T waves during left bundle branch block were in the exact same leads as were the deep negative QRS complexes during ventricular pacing...
November 2014: Journal of Electrocardiology
Henning Teismann, Heike Wersching, Maren Nagel, Volker Arolt, Walter Heindel, Bernhard T Baune, Jürgen Wellmann, Hans-Werner Hense, Klaus Berger
BACKGROUND: Depression and cardiovascular diseases due to arteriosclerosis are both frequent and impairing conditions. Depression and (subclinical) arteriosclerosis appear to be related in a bidirectional way, and it is plausible to assume a partly joint causal relationship. However, the biological mechanisms and the behavioral pathways that lead from depression to arteriosclerosis and vice versa remain to be exactly determined. METHODS/DESIGN: This study protocol describes the rationale and design of the prospective BiDirect Study that aims at investigating the mutual relationship between depression and (subclinical) arteriosclerosis...
2014: BMC Psychiatry
Pablo A Chiale, Daniel Etcheverry, Julio D Pastori, Pablo A Fernandez, Hugo A Garro, Mario D González, Marcelo V Elizari
T wave "memory" is a peculiar variety of cardiac remodeling caused by a transient change in the course of ventricular depolarization (due to ventricular pacing, rate-dependent intraventricular block, ventricular preexcitation or tachyarrhythmias with wide QRS complexes). It is usually manifested by inverted T waves that appears when normal ventricular activation is restored. This phenomenon is cumulative and occurs earlier if the ventricular myocardium has previously been exposed to the same conditioning stimuli...
August 2014: Current Cardiology Reviews
Nico H L Kuijpers, Evelien Hermeling, Joost Lumens, Huub M M ten Eikelder, Tammo Delhaas, Frits W Prinzen
It is not understood why, after onset of left bundle-branch block (LBBB), acute worsening of cardiac function is followed by a further gradual deterioration of function, whereas most adverse cardiac events lead to compensatory adaptations. We investigated whether mechano-electrical coupling (MEC) can explain long-term remodeling with LBBB and cardiac resynchronization therapy (CRT). To this purpose, we used an integrative modeling approach relating local ventricular electrophysiology, calcium handling, and excitation-contraction coupling to global cardiovascular mechanics and hemodynamics...
June 15, 2014: American Journal of Physiology. Heart and Circulatory Physiology
Marcello Costantini
Disorders of intraventricular conduction (bundle branch block and hemiblock) are usually stable and remain unchanged irrespective of heart rate. Not infrequently, however, their appearance is related to the duration of the cardiac cycle, so that they appear and disappear with changes in heart rate. This may not even represent a pathological phenomenon, since sudden and consistent changes in cardiac cycle can result, even physiologically, in aberrant conduction. However, when a bundle branch block appears intermittently for simple and progressive increments, or even deceleration, of the sinus rate, this is related to a true bundle branch pathology, i...
January 2014: Giornale Italiano di Cardiologia
Michał Lewandowski, Andrzej Przybylski, Wiesław Kuźmicz, Hanna Szwed
AIMS: The aim of the study was to analyze the value of a completely new fuzzy logic-based detection algorithm (FA) in comparison with arrhythmia classification algorithms used in existing ICDs in order to demonstrate whether the rate of inappropriate therapies can be reduced. METHODS: On the basis of the RR intervals database containing arrhythmia events and controls recordings from the ICD memory a diagnostic algorithm was developed and tested by a computer program...
September 2013: Annals of Noninvasive Electrocardiology
Evelien Hermeling, Tammo Delhaas, Frits W Prinzen, Nico H L Kuijpers
In the ECG, T- and R-wave are concordant during normal sinus rhythm (SR), but discordant after a period of ventricular pacing (VP). Experiments showed that the latter phenomenon, called T-wave memory, is mediated by a mechanical stimulus. By means of a mathematical model, we investigated the hypothesis that slow acting mechano-electrical feedback (MEF) explains T-wave memory. In our model, electromechanical behavior of the left ventricle (LV) was simulated using a series of mechanically and electrically coupled segments...
October 2012: Progress in Biophysics and Molecular Biology
Andreas A Werdich, Anna Brzezinski, Darwin Jeyaraj, M Khaled Sabeh, Eckhard Ficker, Xiaoping Wan, Brian M McDermott, Calum A Macrae, David S Rosenbaum
Altered mechanical loading of the heart leads to hypertrophy, decompensated heart failure and fatal arrhythmias. However, the molecular mechanisms that link mechanical and electrical dysfunction remain poorly understood. Growing evidence suggest that ventricular electrical remodeling (VER) is a process that can be induced by altered mechanical stress, creating persistent electrophysiological changes that predispose the heart to life-threatening arrhythmias. While VER is clearly a physiological property of the human heart, as evidenced by "T wave memory", it is also thought to occur in a variety of pathological states associated with altered ventricular activation such as bundle branch block, myocardial infarction, and cardiac pacing...
October 2012: Progress in Biophysics and Molecular Biology
Nazira Özgen, Zhongju Lu, Gerard J J Boink, David H Lau, Iryna N Shlapakova, Yevgeniy Bobkov, Peter Danilo, Ira S Cohen, Michael R Rosen
BACKGROUND: Left ventricular pacing (LVP) in canine heart alters ventricular activation, leading to reduced transient outward potassium current (I(to)), loss of the epicardial action potential notch, and T-wave vector displacement. These repolarization changes, referred to as cardiac memory, are initiated by locally increased angiotensin II (AngII) levels. In HEK293 cells in which Kv4.3 and KChIP2, the channel subunits contributing to I(to), are overexpressed with the AngII receptor 1 (AT1R), AngII induces a decrease in I(to) as the result of internalization of a Kv4...
November 2012: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Liliane Wecke, Caroline J M van Deursen, Lennart Bergfeldt, Frits W Prinzen
BACKGROUND AND PURPOSE: Cardiac memory is known as T-wave inversions and other repolarization changes after a period of altered ventricular activation, previously mainly studied in structurally normal hearts. We investigated repolarization changes in failing hearts undergoing cardiac resynchronization therapy (CRT). METHODS: Electrocardiogram and vectorcardiogram were recorded before and 1 day and 2 weeks after initiation of CRT in 23 patients with heart failure and left bundle-branch block...
September 2011: Journal of 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"