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J A Milliken

Publications and source records attributed to J A Milliken.

At least 19 recordsLinked to original sources
PubMed1991

Prediction of left ventricular mass from the electrocardiogram.

Multiple stepwise regression methods were used to derive electrocardiographic (ECG) models for prediction of the echocardiographic left ventricular (LV) mass index from standard 12-lead ECG measurements using data files of 203 men and 252 women. The correlation between echocardiographic and ECG estimates of LV mass index was R2 = 0.58 for men and R2 = 0.42 for women. A separate logistic regression model was derived for classification of LV hypertrophy as a dichotomized dependent variable. This classifier chose R (aVL), T (V6), and S (V1) for men and R (aVL), T (V6), and S (I) for women and produced a moderate sensitivity (53.7% for men and 63.4% for women) and specificity (94.9% for men and 92.9% for women). We conclude that the initial performance of these and other recently developed multivariate estimators of LV mass and LV hypertrophy classifiers is promising enough to subject them to further studies to evaluate their utility as risk predictors.

Adolescent↗
PubMed1985

Electrocardiographic diagnosis of left ventricular hypertrophy in the presence of left bundle branch block: an echocardiographic study.

This study tests the electrocardiographic diagnosis of left ventricular (LV) hypertrophy in the presence of left bundle branch block (BBB). The LV mass of 125 patients with left BBB was estimated by echocardiography. M-mode echocardiography was technically adequate in 80% of patients. LV mass was calculated using previously validated M-mode formulas and then indexed to body surface area. The known shifts in the QRS voltage and axis with the onset of left BBB led to the selection of 4 electrocardiographic parameters for the diagnosis of LV hypertrophy: R in aVL 11 or more; QRS axis -40 degrees or less (or SII greater than RII); SV1 + RV5 to RV6 40 or more; SV2 30 or more and SV3 25 or more; these parameters were used in cumulative fashion. This cumulative approach was superior to using single conventional criterion such as the SV1 + RV5 or RV6. When LV hypertrophy was defined as an M-mode index of at least 115 g/m2, the sensitivity was 75% and specificity 90%. Using an M-mode mass of at least 215 g as the standard, the sensitivity was 73% and the specificity 66%. LV hypertrophy can be diagnosed by electrocardiographic criteria in the presence of left BBB at least as reliably as in normal conduction.

Adult↗
PubMed1983

The impact of an ECG computer analysis program on the cardiologist's interpretation. A cooperative study.

Nine experienced electrocardiographers and the ECG computer program developed in the Veterans Administration (AVA 4.0) were evaluated against ECG-independent evidence of 180 patients' true diagnoses. A cross section of cardiac abnormalities was included. Each reader was given the 12-lead and orthogonal 3-lead ECG. The impact of ECG computer reports on the interpretations by the nine readers was evaluated by comparing their interpretations before and after the addition of a computer report. Using only high probability statements, the average accuracy of ECG diagnosis by the nine readers was 54%. It increased to 62% when the computer report was added. Computer interpretation was correct in 76%. It was shown that the Bayesian classification method together with multivariate analysis, used in the VA program, are mainly responsible for the improvement in diagnostic accuracy.

Angina Pectoris↗
PubMed1983

Isolated and complicated left anterior fascicular block: a review of suggested electrocardiographic criteria.

The electrocardiographic criteria for isolated left anterior fascicular block are reviewed and illustrated. Left anterior fascicular block decreases the voltage in the chest leads and increases the voltage in the limb leads. The usual voltage criteria of left ventricular hypertrophy must be modified appropriately. Changes in repolarization include a decrease in the T wave of leads I and AVL and an increase in leads II, III, AVF, V5 and V6. Small Q waves in V2 may simulate an anteroseptal myocardial infarction. Three criteria for the possible diagnosis of superimposed inferior myocardial infarction have been suggested. Both inferior and anterior myocardial infarctions may be masked by R waves replacing Q waves. In the presence of a recent anterior infarction, right bundle branch block may also be masked. Thus, left anterior fascicular block may mask or mimic infarction and left ventricular hypertrophy and mask right bundle branch block in the setting of an acute anterior myocardial infarction.

Bundle of His↗
PubMed1981

Alternatives in the handling, processing and storage of electrocardiograms.

Physicians and administrators are becoming aware that computer technology can play a significant role in the electrocardiology department. Problems related to the large number of requests for electrocardiograms, the production and communication of electrocardiographic tracings and reports, the access to stored tracings and the overall cost of providing effective services have led administrators to look for assistance through automation. Before expensive equipment and new procedures are introduced, a survey of the electrocardiology department's functions and procedures can lead to important insights. Automation can be achieved in stages, and problems can be solved by separate steps. Options range from basic word-processing support to completely automated electrocardiographic interpretation and computerized storage of records. Choosing the appropriate equipment and programs requires knowledge of the present system, awareness of the options and analysis of the costs and savings.

Computers↗
PubMed1978

Detection of pericardial effusion by chest roentgenography and electrocardiography versus echocardiography.

To determine the sensitivity and specificity of chest roentgenography and electrocardiography in the detection of pericardial effusion, echocardiography was used as the diagnostic standard. Chest roentgenograms and electrocardiograms of 124 patients, 57 of whom had pericardial effusion, were read without knowledge of the echocardiographic interpretation. The sensitivity of roentgenographic diagnosis was low (20%), as was that of diagnosis from decreased voltage on the electrocardiogram (26%). The specificity of the chest roentgenogram was 89% and that of the low-voltage electrocardiogram 97%. The high specificity of the low-voltage electrocardiogram may have been due in part to the exclusion of obese and emphysematous subjects from the study. When cardiomegaly detected roentgenographically or a low-voltage electrocardiogram or both were considered as evidence of pericardial effusion, sensitivity improved to 82% but specificity declined to 29%. It is concluded the chest roentgenography and electrocardiography are unsatisfactory as screening investigations for the detection of pericardial effusion.

Echocardiography↗
PubMed1978

Assessment of the technical quality of electrocardiograms.

The technical quality of 600 electrocardiograms (ECG's) was assessed for missing leads and clipping, and graded from 1 to 5 for each of noise, lead drift and beat-to-beat drift. Three subgroups of 200 ECGs each were studied: group A, those obtained by emergency department staff (non-technicians); group B, records obtained by ECG technicians; and group C, telephone-transmitted records obtained by technicians performing all the laboratory work at a smaller, outlying hospital. Records with missing leads, clipping, grade 4 or 5 noise, grade 5 lead drift or grade 5 beat-to-beat drift were classified as unsatisfactory or rejected. With these stringent criteria the rejection rate was 71.0% for group A records, 58.5% for group B and 44.5% for group C. The proportions of records with peak quality (no missing leads or clipping, and grade 1 noise, lead drift or beat-to-beat drift) were 4.5% for group A, 5.5% for group B and 23.0% for group C. Suggested revisions in the grading of technical quality of ECGs are presented.

Allied Health Personnel↗
PubMed1977

The impact of the computer-reported vectorcardiogram on the cardiologist interpreter of the scalar electrocardiogram.

The purpose of this study was to determine if the computer-reported vectorcardiogram (VCG) had a notable impact on the cardiologist interpreter of the 12-lead scalar electrocardiogram (ECG). Three cardiologists read 100 12-lead scalar ECGs and four months later again read the same tracings while having available the VCG computer report. The diagnosis was altered in 25% of the repeated interpretations. Forty-five per cent of these had only minor changes and can probably be disregarded. Major or significant changes occurred in 14% of the records, and 80% of these were apparently attributable to the computer report. It was concluded that the use of a computer-assisted interpretation of a VCG may enhance the uniformity and consistency of the cardiologist's interpretation of the scalar ECG.

Bundle-Branch Block↗
PubMed1971

Validity of computer interpretation of the electrocardiogram.

Evaluation of the accuracy of computer interpretation of 2019 standard 12-lead ECG's has been carried out. In 762 records defined as normal by the cardiologist the computer agreed in 41%, found 49% with minor "abnormalities" and read 10% as having gross abnormalities.There were 1257 abnormal records. The computer read 43 of these as normal including five with infarction and three with LVH. Agreement in the various abnormal categories ranged from 31% to 85% and even after review disagreement remained in 33% of cases.

Bundle-Branch Block↗