Reference values of Holter electrocardiography in normal horses
6
Citation
10
Reference
20
Related Paper
Citation Trend
Abstract:
The aim of the study was to obtain a set of relevant measurements from healthy, resting horses that can be used as reference values for Holter electrocardiography. Twenty healthy horses (eight mares, two geldings and ten stallions) were selected randomly. The animals varied in age from three to nine years. Electrocardiography was performed at rest in the stable without the presence of the examiner causing additional stress. Each horse was monitored for one hour. P-wave duration, P-wave peak interval, P-R segment, P-R interval, QRS interval, S-T segment, Q-T interval and S-T interval were determined. Median values of the above-mentioned parameters in milliseconds were as follows: 110, 65, 153, 273, 131, 218, 557 and 426, respectively. These values differ significantly from previously published results based on standard electrocardiography.Keywords:
RR interval
PR interval
Cite
The tests were performed on 21 healthy dogs of various breeds and sexes, with body weights from 3 to 70 kg, aged between 1 and 12 years, submitted to the ECG preventive examination. The ECG was performed in a standing position with BTL SD-8 electrocardiographic device and analysed once the recording was enlarged. P-wave duration was calculated in six ECG leads (I, II, III, aVR, aVL, aVF) from five cardiac cycles. The mean Pmax value was determined at 55.8±11.3 ms, Pmin at 38.9±12.5 ms, and Pd at 16.9±9.4 ms. The proper Pd value was determined at up to 36 ms.
Body position
Cite
Citations (5)
Objective To investigate occurrence rate of QRS electrical alternans (QRSEA) among healthy Chinese.Methods 12-lead simultaneous body surface electrocardiogram (12ECG) were taken from 3301 healthy Chinese aged 18～87 years old (mean 43.44±14.47 years) with SR-1000A automated electrocardiography made by Guangdong Zhongshan.The population included 2122 male and 1179 female,were divided three groups (18～39 years,40～59 years and ≥60 years) and subgroups (male,female).The occurrence fate of QRSEA and heart rate (HR) were measured in 12ECG.These data were saved in the floppy disk and statisticsed by SPSS 11.0 software.Results The ocurrence rate of QRSEA was 10.24% and raised with increasing of age.The male was more than female in ≥60 years group (P0.01).QRSEA was appeared durine HR (50～101) beat/min [(mean (69.87±10.06) beat/min).Conclusion There occurrence rate of QRSEA was 10.24% in healthy.It shows no-frequency dependent.
Chinese population
Beat (acoustics)
Body surface area
Cite
Citations (0)
<p>The aim of this study was to provide reference values for a single, popular breed of pet rabbit. Moreover, additional objectives were to determine whether sex, body position or age alter Netherland Dwarf rabbit electrocardiographic variables and whether the use of electrocardiographic filters affects those variables. Forty Netherland Dwarf rabbits were examined clinically and standard six-lead electrocardiograms (ECGs) were recorded in sternal and then dorsal recumbency. At first power-line and anti-drift filters were used and then they were disabled. The following variables were measured in lead II: heart rate; P wave duration and amplitude; P-R interval; QRS duration; R wave amplitude (with and without filters); Q-T interval; T wave duration and amplitude; S-T segment; J-T duration; and mean electrical axis (MEA) (with and without filters). MEA was determined by 3 different methods. After statistical processing of the data, our results showed that there were no significant differences between both recumbencies, with the exception of the J-T duration, which was higher in dorsal recumbency. The R wave amplitude using electrocardiographic filters showed significant differences between males (0.083 mV) and females (0.115 mV; P<0.05); and between younger rabbits (0.108 mV) and older rabbits (0.097 mV; P<0.05). These differences were not shown between R waves with filters disabled. Moreover, the strongest correlation was between 2 MEA methods without filters. MEA was more leftward in the pet rabbit than in other species (dog or cats). In conclusion, electrocardiography recording without electrocardiographic filters should be assessed when it is possible, and the specific ECGs characteristics for Netherland Dwarf rabbit should be taken into account.</p>
Body position
Cite
Citations (2)
Cite
Citations (33)
This study aims to describe and evaluate normal electrocardiographic parameters in calves.Twenty healthy male Holstein calves were included and divided into two groups of 10 animals each. Calves aged between 25 and 30 days have been enrolled in the Group 1. Calves aged between 177 and 183 days have been included in Group 2. The electrocardiogram were recorded with minimal restraint and without any sedation. Standard bipolar (I, II, and III) and augmented unipolar limb (aVR, aVL, and aVF) leads were recorded using 50 mm / sec paper speed and 10 mm = 1 mV for at least 5 minutes. QRS complexes, T and P waves were evaluated for duration and amplitude. The duration of the PR, QT and ST intervals was also measured. The analysis of the electrocardiography traces showed that the morphology of the QRS complex was of type Qr, QS or rS in both groups. The duration and amplitude of P, T waves and QRS complex showed minimal variations between two groups. The duration of the QT and RR intervals was higher in the Group 1 than the Group 2, instead the heart rate was decreased.
Cite
Citations (1)
Abstract: The objective aimed to describe the electrocardiographic behavior of parameters in Holstein pregnant cows and neonates during the perinatal period. The electrocardiograms were performed using a computerized electrocardiogram. The animals selected for the study were 23 cows and 18 neonates. Maternal electrocardiographic examinations were conducted in the 35, 28, 21, 14, 7 days and one-day pre -partum and the neonates were evaluated in six moments; at the time of birth, 7, 14, 21, 28 and 35 days after delivery. The evaluations were done in pre and post-delivery cows and into the group of neonates between female and male. For each electrocardiographic recording P-wave duration and amplitude, PR interval and the QRS complex duration, R, S-wave amplitude and polarity, QT and RR interval duration were examined. Changes in heart rate, ST segment and T wave polarity were recorded in leads of Einthoven and base-apex planes. The mean electrical axis of the QRS complex was calculated. In cows the results when comparing the two leads system, there are significant changes in the amplitude of the waves P, R, S, and T and the duration of the intervals PR, ST and QRS complex. The difference between primiparous and multiparous dairy cows was in the amplitude of the Twave. It was concluded that the base-apex system is a suitable lead for monitoring heart rhythm in Holstein cows and Einthoven in neonates. During the first month of life, no differences in P, Q, S and T waves, in PR, QRS, and ST intervals and in axis orientation was observed in neonates. There was a significant difference in duration of the QT interval. Among sexes, the difference was in the Q amplitude. This study incorporated the calves and Holstein cows in a single study in search of baseline information regarding the duration and morphology of the ECG parameters. In conclusion, it was proved that, with increasing age, there are changes in ECG components associated with variations in the distance between the recording electrode and the heart. The study contributes by providing Holstein reference values for clinical evaluations.
Apex (geometry)
Post partum
Lead (geology)
Cite
Citations (3)
The purpose of this study is to evaluate healthy conscious guinea pigs as a model for electrophysiology assessment and to describe normal electrocardiographic patterns in controlled laboratory environment, establishing the best QT formula for this method. Electrocardiographic recordings of fifty adult conscious guinea pigs were obtained using a computerized electrocardiography. The electrocardiographic measurements of three different tracings were analyzed. The results obtained established normal mean and range values for the parameters: heart rate, waves and intervals of P-QRS-T deflections, as well as the mean cardiac axis. Groups were separated by body weight: group 1 gathered animals with 500-699g and group 2 with animals 700-900g. No differences were found when measurements were compared between groups, showing no significant difference between weight/body sizes to the electrocardiographic parameters (P<0.05). The mean corrected QT values (QTc) obtained using diverse formulae were significantly different (P<0.05), were the most consistent was Van der Water (QTcV). QTcV values were strongly correlated (r=98) and 95% confidence interval 185.7 to 195.2ms.Considering its simplicity and reliability, the QTcV was deemed the most appropriate to be used for the correction of QT interval in conscious guinea pigs.The results of this study also suggest that the values found can be used as reference for the species.
Cavia
PR interval
Cite
Citations (7)
Sudden cardiac death represents a major public health problem, but in the general population the identification of those subjects at very high risk remains poor. Simultaneous multiparametric ECG analysis can improve the identification of high-risk patients.Five-min ECG recordings at a 5 MHz sampling rate (extended length-XL-ECG, Mortara Instruments, Milwaukee, WI, USA) were acquired in 105 healthy subjects (age range 21 to 80 years), equally distributed for age decades and sex, and three additional recordings, 30 min apart, were repeated in 30 subjects on the second day. The following parameters were recorded and analyzed: the RR interval, QRS duration, QT interval corrected according to the Bazett and Fridericia formulae, QT dispersion, T wave complexity, activation-recovery interval dispersion, standard deviation of the RR intervals, filtered QRS duration, the square root of the mean voltage of the last 40 ms of the filtered QRS, and the length of time that the terminal vector magnitude complex remains < 40 microV.QRS duration, activation-recovery interval dispersion, and filtered QRS differed in the two sexes. The standard deviation of the RR intervals, T wave complexity and QT dispersion were significantly correlated with age. The reproducibility was good for each parameter.The XL-ECG allows the simultaneous calculation of eight adequately reproducible different parameters the values of which are in agreement with those of the literature. Thus, XL-ECG is a reliable time- and cost-saving tool.
Coefficient of variation
Cite
Citations (5)
The objective of this study was to evaluate the accuracy of short duration electrocardiographic (ECG) recordings extracted from ambulatory continuous ECG (Holter) to assess 24-hour mean heart rate in dogs with atrial fibrillation. In this retrospective study, Holter recordings obtained from 20 dogs with atrial fibrillation were selected for analysis. Ten out of 20 dogs were receiving drugs to control heart rate at the time of Holter evaluation. From the Holter recordings, heart rate averages were calculated for various sample durations (five-minutes, 30 minutes, one-hour, two-hours, and three-hours) for each dog. Percentage of these shorter duration ECG obtained HR averages that fell within ±10%, ±15% and ± 20% of 24-hour mean heart rate was determined for each sample duration and for each dog. Seventy five percent of heart rate averages obtained from three-hour ECG recordings fell within ±10% of 24-hour mean HR. All the heart rate averages obtained from two-hour ECG recordings fell within ±20% of 24-hour mean heart rate. Based on the results of this study it can be concluded that the duration of the ECG recording affects the prediction accuracy for 24-hour Holter mean HR. Only two and three hours of Holter recordings provided all heart rate averages within ±20% of 24-hour mean heart rate. No significant differences were noted in the prediction accuracy of shorter duration ECG recordings based on rate control therapy status. Further prospective studies are needed to assess the accuracy of HR obtained at home using various ECG recording devices to predict 24-hour mean heart rate in dogs with atrial fibrillation.
Cite
Citations (1)
To study the effect of sampling rate on automated QT measurements, Holter ECGs were recorded at 180 and 1000 samples/second (s/s) using 2 recorders; 30 ECG snapshots were extracted at varying heart rates from 16 healthy subjects and re-sampled to 180, 500 or 1000s/s using the Antares software. QT interval by CalECG algorithm was longer (5.0±6.3 ms, p<0.001) in 180s/s ECGs than in 1000s/s ECGs. It decreased to 2.1±5.8ms when 180s/s ECGs were re-sampled to 500s/s, and to 2.6±6.2ms at 1000s/s. It also decreased progressively on resampling both sets of ECGs to 1000s/s (2.6±6.2ms), 500s/s (1.8±5.5ms) and 180s/s (0.4±5.9ms). Differences in QT interval were independent of the QT measurement algorithm used: University of Glasgow (Uni-G) program and CalECG for 500s/s ECGs; Veritas and CalECG for 1000s/s ECGs. Thus, QT interval is longer in ECGs with lower sampling rates; resampling them to a higher resolution partially compensates for this.
Resampling
Cite
Citations (1)