Abstract:
:In 19 pentobarbital anesthetized dogs subjected to right thoracotomy, plunge wire and catheter electrodes were positioned to record and pace from the high right atrium, coronary sinus os, aortic root (for His bundle electrograms), and the right ventricular outflow tract and apex. A deflectable-tip catheter electrode was placed under the septal tricuspid leaflet for pacing the right ventricular septal crest. Electrocardiographic leads II and aVR were also recorded during atrial and ventricular pacing in the control state and during low- and high-intensity left vagosympathetic trunk stimulation. Pacing from each A or V site in 12 dogs showed normal atrioventricular (AV) and ventriculoatrial (VA) conduction over a wide range of heart rates (120-360 beats/min) with progressive AV and VA delay at each heart rate until Wenckebach cycles occurred (AV Wenckebach cycle averaged 325 +/- 44 beats/min; VA Wenckebach cycle averaged 246 +/- 52 beats/min). In two dogs, pacing from the coronary sinus os showed a 30-beat/min difference in the Wenckebach cycle rate compared to high right atrium pacing, and the AH intervals for the former were relatively insensitive to vagosympathetic trunk stimulation compared with the latter. In five other dogs, retrograde VA and HA intervals showed little, if any, decrement over a wide range of heart rates, with no immediate response to low-intensity vagal stimulation. After 7-22 seconds of continuous vagal stimulation, VA intervals abruptly prolonged and/or blocked. In all, second-degree heart block occurred at ventricular pacing rates > or = 300 beats/min in the form of atypical Wenckebach cycles. In all cases, the earliest atrial activation, as measured by a close bipolar probing electrode, was in the posterior septum adjacent to the coronary sinus os. In one dog, VA block occurred as a Mobitz type II with paroxysmal complete VA block (sinus escape rhythm) during continuous ventricular pacing at 330 beats/min. After radiofrequency ablation of the earliest atrial activation site typical VA Wenckebach cycles, immediately responsive to vagal stimulation, was then observed at a ventricular pacing rate of 150 beats/min. These data suggest that AV and VA connections in some canine hearts show varying degrees of bypass of the AV node, similar to cases reported in the clinical literature.
journal_name
J Electrocardioljournal_title
Journal of electrocardiologyauthors
Scherlag BJ,Munsif A,Nakagawa H,Hirao K,Lazzara Rsubject
Has Abstractpub_date
1993-01-01 00:00:00pages
227-37eissn
0022-0736issn
1532-8430journal_volume
26 Supplpub_type
杂志文章abstract::Patients with paroxysmal atrial fibrillation (AF) have greater overall P wave magnitude than control subjects, but the temporal localization of the increased energy is unknown. P wave spectral turbulence has not been investigated in such patients, and the optimum methodology for studying P wave signals has not been de...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(97)80013-1
更新日期:1997-04-01 00:00:00
abstract:BACKGROUND:The prevalence and determinants of QRS transition zones are not well established. METHODS:We examined the distributions of Normal, clockwise (CW) and counterclockwise (CCW)) QRS transition zones and their relations to disease, body size and demographics in 4624 black and white men and women free of cardiova...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2017.10.004
更新日期:2018-01-01 00:00:00
abstract::Intracellular and extracellular recording techniques were used to study triggered activity in tissues isolated from the inferior right atrium of the dog. In the presence of norepinephrine (greater than 10(-7) M) single stimuli or short rapid pacing elicited action potentials with delayed after-depolarizations, leading...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/0022-0736(87)90005-7
更新日期:1987-01-01 00:00:00
abstract::Previous studies indicate that the predictive value of atrial fibrillatory rate in patients undergoing cardioversion of atrial fibrillation (AF) of long duration is limited. The present study investigates signal entropy in this setting. Standard 12-lead electrocardiograms (ECGs) were recorded from 66 consecutive patie...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2010.10.033
更新日期:2011-03-01 00:00:00
abstract:BACKGROUND:There is a controversy regarding the association between QRS width and ventricular arrhythmias (VAs). We hypothesized that predictive value of the QRS width could be improved if QRS width were considered in the context of the sum magnitude of the absolute QRST integral in 3 orthogonal leads sum absolute QRST...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2010.07.013
更新日期:2010-11-01 00:00:00
abstract::In order to compare the prevalence of electrocardiographic (ECG) abnormalities suggestive of right ventricular hypertrophy in native and immigrant populations residing at high altitude, a retrospective review was undertaken of data obtained from a random survey of healthy volunteers and persons with chronic mountain s...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:
更新日期:1998-07-01 00:00:00
abstract:INTRODUCTION:Measures of heart rate variability (HRV) can be divided in time domain and frequency domain parameters. It is frequently ignored that estimation of frequency-domain parameters is a 2-step procedure where statistical error from the first step (spectral estimation) is neglected in subsequent analyses. METHO...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2008.02.014
更新日期:2008-07-01 00:00:00
abstract::Forty-three patients with their first acute inferior wall myocardial infarction (IWMI) were divided into three groups according to the R/Q ratio in standard lead II. This was done to correlate these groups with the characteristic course of electrocardiographic stages. The R/Q ratio was measured on the ninth day of fol...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/0022-0736(88)90105-7
更新日期:1988-11-01 00:00:00
abstract::A 66-year-old woman with a long history of hypertension had an electrocardiogram with giant negative U waves in left precordial leads despite hypokalemia. This seems to be the first report of giant negative U waves induced by uncontrolled hypertension with hypokalemia. The occurrence of negative U waves in the presenc...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/0022-0736(92)90121-f
更新日期:1992-04-01 00:00:00
abstract::Sudden cardiac death occurs as a result of a complex interplay of changes in myocardial substrate, imbalance of autonomic regulation of the heart, and myocardial vulnerability. Noninvasive electrocardiology serves as a comprehensive tool for investigating factors representing mechanistic pathways leading to cardiac ev...
journal_title:Journal of electrocardiology
pub_type: 杂志文章,评审
doi:10.1016/j.jelectrocard.2003.09.022
更新日期:2003-01-01 00:00:00
abstract::The electrocardiographic transient display of left ventricular hypertrophy (LVH), during rapid heart rates, in the setting of sinus/supraventricular tachycardias and atrial fibrillation, is illustrated via 3 case reports. This common occurrence is expressed by an increase in the S-waves in leads V2-V5, during tachycar...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2021.01.001
更新日期:2021-01-09 00:00:00
abstract::Ventricular fibrillation (VF) is the most common arrhythmia leading to sudden cardiac death, but in rare cases VF can manifest as a syncope, provided that it will self-terminate. We present a case of a 45-year old female with a history of unexplained syncopal episodes despite exhaustive diagnostics. Implantable loop r...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2018.04.006
更新日期:2018-01-01 00:00:00
abstract::Thoracic electromaps were recorded before and after sublingual nitroglycerin (NG) in 26 subjects 15 and 30 days after acute myocardial infarction (MI), in order to evaluate the effect of the drug on injury potentials. Ten patients with documented left ventricular aneurysm were also studied 5 to 46 months after acute M...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(81)81007-2
更新日期:1981-10-01 00:00:00
abstract::We have developed a computer program which simulates a paced cardiac rhythm strip, graphically generating the electrocardiogram (ECG) on a color monitor. Any pacemaker, programmed as desired, dynamically interacts with a preselected intrinsic rhythm. Utilizing symbols prevalent in the pacing industry, this graphics-or...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:
更新日期:1987-10-01 00:00:00
abstract::In the last 10 years the molecular substrate of a diversity of primary electrical diseases has been unraveled. Disease-causing mutations in ion-channel genes have been identified and have challenged clinical and basic electrophysiologists to mechanistically link the observed genetic aberrancies to the phenotype. Indee...
journal_title:Journal of electrocardiology
pub_type: 杂志文章,评审
doi:10.1016/j.jelectrocard.2005.06.103
更新日期:2005-10-01 00:00:00
abstract:INTRODUCTION:The right ventricular myocardial infarction (RVMI) has traditionally been mainly related to inferior wall ST elevation myocardial infarction (STEMI). This study assessed the RVMI electrocardiographic (ECG-RVMI) signs in relationship to ECG-based STEMI localization and to the infarct related artery in patie...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2016.08.001
更新日期:2016-01-01 00:00:00
abstract::Under hypoxic (95% N2 + 5% CO2) perfusion, electrophysiological effects of L-carnitine on canine papillary muscles were studied using standard microelectrode techniques. During hypoxic perfusion for 60 min, resting membrane potential (RMP), action potential amplitude (APA) and maximum upstroke velocity of phase 0 were...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(84)80030-8
更新日期:1984-01-01 00:00:00
abstract::A 63 year old man with angina pectoris was found to have frequent extrasystoles separated by odd as well as even numbers of conducted sinus beats. Analysis of 935 conducted sinus beats showed that premature ventricular beats without interpolation were separated by odd numbers of conducted sinus beats in 117 sequences ...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(82)80033-2
更新日期:1982-01-01 00:00:00
abstract::Body surface potential mapping is superior to 12-lead electrocardiogram in detection of acute and old myocardial infarctions. We examined the capability of the ST-T integral and T wave to detect exercise-induced ischemia in body surface potential mapping. Body surface potential mapping with 123 channels was recorded i...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1054/jelc.2003.50013
更新日期:2003-04-01 00:00:00
abstract:BACKGROUND:Accurate measurement of QRS complex duration (QRSd) remains crucial for the selection of patients for cardiac resynchronization therapy (CRT). However, assessment of QRSd on conventional surface electrocardiograms (ECG), especially when performed without computer assistance, may be challenging due to the lim...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2019.08.011
更新日期:2019-01-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Descriptions of the significance of ST segment or QRS abnormalities in myocarditis are limited because documentation of the diagnosis has previously required myocardial biopsy. Late gadolinium enhancement (LGE) and T2 weighted imaging in the midventricular wall on cardiac magnetic resonance imagi...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2014.07.018
更新日期:2014-11-01 00:00:00
abstract:OBJECTIVE:We have previously used a 12-lead, signal-processed ECG to calculate blood potassium levels. We now assess the feasibility of doing so with a smartphone-enabled single lead, to permit remote monitoring. PATIENTS AND METHODS:Twenty-one hemodialysis patients held a smartphone equipped with inexpensive FDA-appr...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2017.06.008
更新日期:2017-01-01 00:00:00
abstract::In treating atrial fibrillation (AF) the goal of ventricular rate reduction is still not determined. An animal model of AF was developed in which the relationship between ventricular rate and the parameters of cardiac function in AF can be studied. To simulate AF, complete heart block was chemically produced on open-c...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(05)80100-1
更新日期:1994-04-01 00:00:00
abstract::Quantitative analysis of ST-segment deviations (STdev) and their resolution by treatment (STR; calculated from a combined sum of STdev in multiple leads) are used in trials on reperfusion for myocardial infarction (MI). Unreadable or unavailable electrocardiogram (ECG) leads are a common reason for exclusion, decreasi...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(03)00030-x
更新日期:2003-07-01 00:00:00
abstract::The purpose of this experiment is to study the possibility of intra-QRS high-frequency electrocardiographic (HFECG) changes for the evaluation of and recovery from myocardial ischemia in both the time-domain and spectral-turbulence analyses on the signal-averaged ECG using the Holter ECG monitoring (Holter SAECG) syst...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(95)80064-6
更新日期:1995-01-01 00:00:00
abstract::In this study it is analyzed by linear and non-linear methods, how the control of instantaneous heart rate (IHR) develops in infants in quiet and active sleep. Ten healthy and term newborns were studied during their first half year of life. Low (LF) and high frequency power (HF) of the spectrum, and the largest Lyapun...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(05)80064-0
更新日期:1995-10-01 00:00:00
abstract::We report a case of ST segment elevation and PR depression in inferolateral leads in a patient with small bowel occlusion and gastric distension that disappeared immediately after gastric evacuation. Contrary to prior reports, we believe that these ECG changes do not represent an intrinsic cardiac electrical abnormali...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2019.08.044
更新日期:2019-01-01 00:00:00
abstract::A 38-year-old African American male patient with a past medical history of human immunodeficiency virus and schizophrenia who was noncompliant with medications presented to the emergency department (ED) after activation of the local crisis response center for altered mental status. Upon arrival he was lethargic and un...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2017.01.012
更新日期:2017-01-01 00:00:00
abstract::There is increasing evidence that regular intense endurance exercise can promote structural and electrical remodeling of the right ventricle (RV). These physiological changes can be profound and are frequently accompanied by ECG changes in the right precordial leads, thereby mimicking features observed in arrhythmogen...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2015.03.001
更新日期:2015-05-01 00:00:00
abstract::Frank-lead electrocardiograms (ECGs) were recorded from 59 adult males with suspected coronary artery disease. Three records were recorded consecutively on frequency modulated tape for each patient in (1) supine position, (2) sitting position with arms relaxed, and (3) sitting position on bicycle with arms on bicycle ...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(76)80021-0
更新日期:1976-01-01 00:00:00