David Littmann

The natural history of congestive heart failure.

The natural history of a disease has, in recent years, come to mean the nonsurgically treated progress of that illness, But is it proper to consider the medically managed course as natural? Is ther...

Correlations of the Orthogonal Electrocardiogram and Vectorcardiogram with Constitutional Variables in 518 Normal Men

Correlations were computed between 333 different electrocardiographic measurements and constitutional variables of 518 normal men. The variables consisted of age, body weight, height, chest configuration, race, and deviations from ideal weight according to height. The most significant correlations were encountered with age. With every decade of life, QRS amplitude measurements decreased at an average rate of 6.5%. Although less in absolute voltage terms, amplitude decreases with age were even more significant for the ST-T complex where the average decline was 9.75% for each decade. Comparison of records from white and Negro subjects revealed marked differences. Most amplitude measurements were higher in the latter group. Furthermore, configurations of leads X and Y differed significantly, with smaller Q/R ratios in Negroes. These findings strongly suggest reevaluation of diagnostic criteria according to race both for recognition of ventricular hypertrophies and myocardial infarcts. Correlations with chest configuration revealed a large number of differences but their significance level was relatively low. Body weight appeared to exert a stronger influence upon the ECG. Obesity led to decreases in amplitude and QRS rotations in superior and anterior directions. Correlations with deviations from ideal weight, calculated according to body height, did not exceed the significance level of those obtained with weight only. Body height appeared to exert the least influence upon the electrocardiogram. The results of the correlations emphasize the need for stratification of ECG data according to constitutional variables, particularly for age, race, and body weight. Use of this information will lead to enhancement of diagnostic ECG differentiation and serve as a basis for epidemiological investigations, particularly studies on aging.

Clinical application of a second generation electrocardiographic computer program

An electrocardiographic computer program based on multivariate analysis of orthogonal leads (Frank) was applied to records transmitted daily by telephone from the Veterans Administration Hospital, West Roxbury, Mass., to the Veterans Administration Hospital, Washington, D. C. A Bayesian classification procedure was used to compute probabilities for all diagnostic categories that might be encountered in a given record. Computer results were compared with interpretations of conventional 12 lead tracings. Of 1,663 records transmitted, 1,192 were selected for the study because the clinical diagnosis in these cases could be firmly established on the basis of independent, nonelectrocardiographic information. Twenty-one percent of the records were obtained from patients without evidence of cardiac disease and 79 percent from patients with various cardiovascular illnesses. Diagnostic electrocardiographic classifications were considered correct when in agreement with documented clinical diagnoses. Of the total sample of 1,192 recordings, 86 percent were classified correctly by computer as compared with 68 percent by conventional 12 lead electrocardiographic analysis. Improvement in diagnostic recognition by computer was most striking in patients with hypertensive cardiovascular disease or chronic obstructive lung disease. The multivariate classification scheme functioned most efficiently when a problem-oriented approach to diagnosis was simulated. This was accomplished by a simple method of adjusting prior probabilities according to the diagnostic problem under consideration.

Persistence of the juvenile pattern in the precordial leads of healthy adult negroes, with report of electrocardiographic survey on three hundred negro and two hundred white subjects

Abstract 1. 1. In an electrocardiographic survey of 500 healthy adults, 300 Negro and 200 white subjects, diphasic or inverted T waves in the precordial leads were observed in 14 Negroes, eight among 100 women and six among 200 men. Among white subjects a diphasic T wave was noted in only one instance. 2. 2. It is suggested that the presence of diphasic or inverted T waves in the precordial leads under the circumstances constituted a persistence of the juvenile pattern and was not a manifestation of organic heart disease.

Electrocardiographic changes in hypertrophic subaortic stenosis which simulate myocardial infarction

Abstract Electrocardiographic findings simulating myocardial infarction are reported in 4 young persons in whom a diagnosis of hypertrophic subaortic stenosis was proved or considered clinically. The pathology of this condition is reviewed. Although the electrocardiographic abnormalities may be helpful in making the diagnosis, their association with it remains speculative.

Total Electrical Alternation in Pericardial Disease

Simultaneous electrical alternation of atrial and ventricular components can occur in malignant and sometimes tuberculous pericardial disease and is due, apparently, to a rotary pendular movement of the heart at a rate that differs from the pulse. This oscillation occurs only during effusion with tamponade and clears with paracentesis. It is thought to be the result of unusual freedom or release from the normal pulmonary and thoracic restraints.

Computer analysis of the orthogonal electrocardiogram and vectorcardiogram in 939 cases with hypertensive cardiovascular disease.

Abstract Orthogonal ECGs (Frank system) were recorded from 939 male patients with hypertensive cardiovascular disease (HCVD) and were compared with records from 229 normal subjects, matched for age, race, and sex. The hypertensive subjects were divided into three clinical groups: (1) patients without cardiac enlargement by chest x-ray and no history of congestive heart failure (CHF), (2) patients with cardiac enlargement but without past or present CHF, and (3) patients with cardiac enlargement and one or more episodes of CHF. A sustained blood pressure level of 15090mm. Hg or more was present in all cases. First an attempt was made to identify optimal scalar and vectorial ECG measurements for discriminating between HCVD and normal, testing a total of 333 variables. With four scalar measurements at a specificity level of 95 per cent, 24 per cent of Group 1, 37 per cent of Group 2, and 44 per cent of Group 3 could be correctly classified. Vector measurements were found mostly redundant. Using linear discriminant function analysis and a likelihood ratio test with 13 different ECG variables at a level of specificity of 95 per cent, it was possible to identify correctly 53 per cent, 75 per cent, and 87 per cent of Groups 1, 2, and 3, respectively. Comparison of results with other reports on ECG changes caused by left ventricular overload (LVO) suggested that the degree of LVO in HCVD, even in the most advanced Group 3, was considerably less than that reported in patients with valvular heart disease with the only exception of terminal cases with HCVD who had come to autopsy. Antihypertensive therapy was considered as one factor which might have contributed to this finding. Multivariate ECG analysis was found an efficient means for diagnostic classification, leading to results which equalled those reported for multiple dipole analysis. As compared to scalar or vector measurements, either used individually or in combination, the multivariate technique exceeded all of these methods for LVO diagnosis by a wide margin when specificity was kept at a constant level.

Alternation of the Heart

Alteration of the heart occurs whenever any of its tissues, contractile or conductive, fail to function during alternate beats. This results in a diversity of 2:1 conduction blocks with electrical alternation and myocardial blocks that produce alternation of the pulse. In a general way, the more distal blocks, involving bundle branches, arborization, and myocardium are the more ominous, implying serious underlying heart disease. They can occur normally, however, at rapid heart rates.Another type of alternation involving atrial as well as ventricular waves is sometimes seen in serious pericardial disease with effusion. It is believed to be due to an unusual rotary oscillation of the heart released from its normal inhibitory mediastinal restraints by the surrounding effusion. This is an anatomic rather than a cellular form of alternation and can exhibit other mechanical disorders such as alternating friction sounds.

Acute Atypical Coronary Artery Insufficiency Incidence and Clinical Course

Not all patients with acute coronary thrombosis or inadequacy develop classic myocardial infarction. Almost 30 per cent of such patients were found to have atypical and apparently less extensive myocardial injury as estimated by the clinical and electrocardiographic findings. The morbidity as well as the mortality was of a lesser order and a somewhat different therapeutic regimen could be employed.

Wolff-Parkinson-White syndrome

Abstract 1. 1. Nine patients who showed the Wolff-Parkinson-White Syndrome are presented and a few of the variations encountered are discussed. 2. 2. The various theories advanced in the explanation of the pathogenesis are referred to and an evaluation of their merits is attempted. In our opinion the most acceptable explanation is that which assumes the presence of one and frequently several accessory conduction pathways which result in “fusion beats.” 3. 3. The influence of quinidine, atropine, and exercise on the “short P-R, long and aberrant QRS” is discussed. In borderline cases these changes may be employed as a diagnostic test. 4. 4. The relationship of myocardial disease to the Wolff-Parkinson-White syndrome is discussed. Several of the patients reported in this paper had systemic disease and two showed definite electrocardiographic abnormalities during periods of normal conduction.