Lead V4R Research Articles

Value of electrocardiogram in diagnosing right ventricular involvement in patients with an acute inferior wall myocardial infarction.

To study the value of the electrocardiogram in diagnosing right ventricular involvement in acute inferior wall myocardial infarction, the electrocardiographic findings were analysed in 67 patients who had had scintigraphy to pin-point the infarct. All 67 patients were consecutively admitted because of an acute inferior wall infarction. A 12 lead electrocardiogram with four additional right precordial leads (V3R, V4R, V5R, and V6R) was routinely recorded on admission and every eight hours thereafter for three consecutive days. Thirty-six to 72 hours after the onset of chest pain a 99mtechnetium pyrophosphate scintigraphy and a dynamic flow study were performed to detect right ventricular involvement, which was found in 29 of the 67 patients (43%). ST segment elevation greater than or equal to 1 mm in leads V3R, V4R, V5R, and V6R is a reliable sign of right ventricular involvement. ST segment elevation greater than or equal to 1 mm in lead V4R was found to have the greatest sensitivity (93%) and predictive accuracy (93%). The diagnostic value of a QS pattern in lead V3R and V4R or ST elevation greater than or equal to 1 mm in lead V1 was much lower. ST segment elevation in the right precordial leads was short lived, having disappeared within 10 hours after the onset of chest pain in half of our patients with right ventricular involvement. When electrocardiograms are recorded in patients with an acute inferior wall infarction within 10 hours after the onset of chest pain, additional right ventricular infarction can easily be diagnosed by recording lead V4R.

The early recognition of right ventricular infarction: diagnostic accuracy of the electrocardiographic V4R lead.

The sensitivity and specificity of ST-segment elevation in the right precordial lead V4R as an early indicator of right ventricular infarction were examined in a consecutive series of 110 patients admitted for acute inferior myocardial infarction. The sensitivity was 82.7%, the specificity 76.9% and the positive predictive value 70% in 58 patients with right ventricular infarction documented by autopsy or a combination of radionuclide ventriculography and one or more of the following tests: echocardiography, technetium-99m pyrophosphate scintigraphy and hemodynamic monitoring. The negative predictive value was 87.7%. Because of its simplicity and its high sensitivity and specificity, recording of V4R should be an intrinsic part of the early evaluation and electrocardiographic examination of acute inferior wall infarction.

Selective criteria for differential diagnosis of infants with symptoms of congenital heart disease.

147 case records of infants referred to the Brompton Hospital in the first year of life with a provisional diagnosis of congenital heart disease were examined. Statistical analyses were performed to evaluate selective criteria for the allocation of these infants into a group with lung disease, or into 1 of 5 major haemodynamic groups--namely, acyanotic, complete transposition of the great arteries, pulmonary outflow tract obstruction, common mixing situations, or hypoplastic left heart syndrome. Arterial PO2 in high oxygen concentration, cardiothoracic ratio, and pulmonary vascular markings on the admission chest x-ray; respiratory rate; P-wave morphology, the electrical sign of the T-wave in lead V4R, and the presence or absence of Q-waves in leads V4R and v6 on the electrocardiogram were significant. A decision tree for the differential diagnosis of infants with suspected congenital heart disease into 5 haemodynamic groups and a group with lung disease is presented, and its predictive value is assessed.

Electrocardiogram in double chamber right ventricle

Thirty patients with a double chamber right ventricle were seen during a 7 year period. The majority of patients had associated cardiac anomalies, most commonly a ventricular septal defect. In this series, as in others, the history, clinical examination, chest roentgenogram and echocardiogram were inconclusive for diagnosing double chamber right ventricle. Symptoms were generally related to the severity of the associated anomalies. In 40 percent of the patients reviewed, upright T waves were found in lead V3R as the only electrocardiographic finding suggestive of right ventricular hypertrophy. Because upright T waves in lead V3R in the absence of other evidence of right ventricular hypertrophy are not commonly seen in patients with an isolated ventricular septal defect or a defect associated with other forms of right ventricular outflow obstruction, this finding should alert the cardiologist to the possibility of the presence of double chamber right ventricle prior to cardiac catheterization.

Prediction of the Site of Coronary Artery Lesion in Acute Inferior Myocardial Infarction with Right Sided Precordial Lead (V4r)

Background: The patient with inferior wall AMI, site of culprit lesions is an important determinant of outcome. Patient with RV infarction have a poor prognosis whereas those with occlusion of LCX have a good prognosis. Early diagnosis and treatment substantially reduce cardiac events particularly in high-risk patients. V4R can be used as to locate the site of obstruction. Materials and methods: 81 patients with acute inferior myocardial infarction admitted to the coronary care unit (CCU) within 12 hours after the onset of chest pain who underwent coronary angiogram were included in the study. Standard 12-lead ECG with right precordial lead V4R was recorded. Patients were categorized into within 3 groups according to early changes of V4R-Group- I - ST-segment elevation > 1 mm and positive T- wave, Group-II- ST-segment iso-electric and positive T-wave, Group-III- ST-segment depression >1 mm and negative T -wave. Results: In group I patients, highest percentage of the patients had lesion in proximal RCA (97.2%); whereas in group II patients, highest percentage in the distal RCA (89.7%) followed by LCX (41.4%) and in group III patients, highest percentage also in LCX (100.0%) followed by LAD (56.3%). Based on analysis of sensitivity and specificity, it was revealed that in group I patients of ECG finding suggested 100.0% sensitivity, 97.8% specificity and 98.8% accuracy. In group II patients, 92.9% sensitivity, 94.3% specificity and 93.8% had accuracy. In case of group III patients, 93.8% sensitivity, 98.5% specificity and 97.5% accuracy. Conclusion: The configuration of the ST-T segment in lead V4R is a sensitive and specific tool to recognize the occluded vessel in acute inferior MI whether it is proximal RCA, distal RCA or LCX. Since it is an inexpensive method, it can be readily used to locate the site of occlusion in AMI - Inferior. Keywords: Coronary artery disease; Myocardial infarction;, Lead V4r. DOI: http://dx.doi.org/10.3329/cardio.v4i1.9389 Cardiovasc. J. 2011; 4(1): 46-52

A Study on Electrocardiograms of Healthy Japanese Children

The purpose of this study is to obtain the normal ranges of electrocardiograms of Japanese elementary school children and to compare with each group separated by age and sex. Materials and Methods The subjects were 984 healthy children (506 boys and 478 girls) selected at random from all children (3532 boys and girls) in an elementary school in Nagoya, Japan. They were accepted as healthy children on the basis of their daily unrestricted activity and through a series of medical examinations. The subjects were sub-divided into twelve groups by sex and age for further analysis of their electrocardiograms. The 12 conventional leads and Lead V3R were recorded for all subjects. The amplitudes and intervals of electrocardiographic deflections were carefully measured in each lead. In this paper 95 percentile of frequency distribution was accepted as a normal range for each component of the record. Results and Discussion RR interval was longer with increasing age both in boys and girls. The increasing rate of RR interval was more prominent in the boys than in the girls, and the difference of mean RR intervals reached a statistical significant level in the groups of 10 and 11 years old. According to above data, it was concluded that the normal range of RR interval should be set up separately; 0.48 to 1.00sec. for 6-9 years, and 0.54 to 1.08 sec. for 10-11 years. Although PQ interval also increased along with age, no significant difference was found for boys and girls. The normal ranges of PQ interval were 0.12 to 0.18 sec. for 6-9 years and 0.13 to 0.19sec. for 10-11 years respectively. The increasing rate of QT interval was less remarkable than RR or PQ intervals, and the mean of boys was significantly longer than that of girls in elder age group. A single normal range could be accepted for QT intervals as 0.28 to 0.40sec. for the all age groups. Though PQ interval tended to be longer with increasing RR interval except in the group with tachycardia, no significant correlation was observed for PQ and RR intervals. Correlation coefficients of RR with QT intervals were very high and proved statistically significant both in boys and girls and for all age groups.