Eliot Young

Electrocardiographic, arteriographie and ventriculographic correlations in transmural myocardial infarction☆

Abstract To determine if significant interrelations exist between the electrocardiographic diagnosis of transmural myocardial infarction, sites of coronary arterial obstruction, and left ventricular asynergy, 235 patients with angiographically documented coronary artery disease were subdivided according to the electrocardiographic location of the myocardial infarction, the coronary arterial system involved and the site of ventricular asynergy. Of 82 instances of anterior myocardial infarction, the left anterior descending artery demonstrated significant disease in 79 (96 percent). Of 100 instances of inferior myocardial infarction, the right coronary artery was significantly diseased in 87 and the left circumflex in 55. When multiple infarctions were present, multivessel disease was found in 93 percent of patients. Left ventricular asynergy was present in 81 percent, including 84 percent of those with anterior infarction, 74 percent of those with inferior infarction, and 93 percent of those with multiple infarctions. The results of our study suggest that the electrocardiogram is often of value in indicating sites of coronary arterial obstruction and ventricular asynergy in patients with coronary artery disease and transmural myocardial infarction.

Natural history of S-T segment elevation after acute myocardial infarction

Clinical, electrocardiographic and cineventriculographic data in two patient groups were analyzed to define the natural history of S-T segment elevation after myocardial infarction. In sixteen of 22 patients (73 percent) with acute inferior myocardial infarction, S-T segment elevation was present on hospital admission, persisting in 1 (5 percent) by the 2nd week. S-T segment elevation was present on admission in 18 of 23 patients (78 per cent) with acute anterior myocardial infarction and persisted in 13 after 1 week and in 9 of 14 (64 percent) during a follow-up period of 1 to 6 months. S-T segment elevation lasting more than 2 weeks after myocardial infarction did not resolve. Compared with patients with inferior myocardial infarction or anterior infarction without persistent S-T segment elevation, patients with anterior infarction and persistent S-T segment elevation had a higher level of mean maximal serum creatine phosphokinase (CPK), more severe left ventricular decompensation and a greater frequency of death in the early follow-up period. In a separate series of 95 patients with cineangiographically documented coronary artery disease, 40 of 65 patients (62 percent) with advanced anterior and apical asynergy had persistent S-T segment elevation. By contrast, only 1 of 30 (3 percent) with coronary disease and normal ventriculograms had persistent S-T segment elevation. We concluded that (1) the natural history of S-T segment elevation after myocardial infarction is resolution within 2 weeks in 95 percent of inferior but in only 40 percent of anterior infarctions; (2) S-T segment elevation persisting more than 2 weeks after myocardial infarction does not resolve; (3) persistent S-T segment elevation is associated with clinically more severe myocardial infarction; and (4) in patients with coronary artery disease, persistent S-T segment elevation after myocardial infarction is a specific but insensitive index of advanced asynergy.

Electrocardiogram and Vectorcardiogram in Myocardial Infarction

Y THE TIME the patient with acute myocardial infarction is first examined, his electrocardiogram may already show changes in the RS-T segment alone, in the T wave alone, in the QRS complex alone, or in any combination of the three. Changes in any of these portions of the ventricular complex and particularly in the QRS may not appear for hours or days. Some never show distinctive electrocardiographic changes; in these the diagnosis must rest upon other than electrocardiographic evidence. The changes in the QRS complex generally long outlast the changes in RS-T and T and ordinarily constitute the telltale evidence of previous infaretion for the remainder of the patients life.

The normal vectorcardiogram. I

Summary The horizontal, sagittal, and frontal planar projections of the spatial vector-cardiogram are described for 100 normal subjects. The Trihedron reference system was used. Emphasis is placed upon a method of analysis that may be applied to any reference system. A detailed study is presented of the general morphology, position, and magnitude of QRS and T vectors, their direction and speed of inscription, the interrelationships of various portions of the QRS loop, and of the latter to the T loop.

Continuous Hypothermic Arrest Versus Intermittent Ischemia for Myocardial Protection During Coronary Revascularization

Abstract To assess the safety of two commonly used methods of myocardial protection, 144 consecutive patients who underwent coronary artery bypass grafting for chronic disabling or unstable angina were studied. Profound local cardiac hypothermia (LCH) with a single continuous period of ischemic arrest was used in 71 patients and compared with intermittent ischemia with intervening periods of reperfusion in 73 patients. Both groups were similar in age, sex distribution, number of obstructed coronary arteries, and number of coronary arterial bypass grafts performed. The electrocardiogram, serum glutamic oxaloacetic transaminase (SGOT), lactate dehydrogenase (LDH), and creatine phosphokinase (CPK) were measured preoperatively, the day of operation, and for two days postoperatively. The operative mortality was 0.7%. The overall perioperative myocardial infarction rate defined by QRS criteria was 6.3%. In the LCH group the infarction rate was 4.2%, and in the ischemia group, 8.2%. Although mean initial postoperative SGOT and LDH were noticeably lower in the LCH group, other enzyme values, including CPK, did not differ noticeably between the groups. These data indicate that a single continuous period of ischemic arrest with profound local cardiac hypothermia as well as intermittent aortic cross-clamping with moderate systemic hypothermia are safe techniques for protecting the myocardium during coronary revascularization.

The normal vectorcardiogram of children

Abstract The normal vectorcardiogram, as analyzed by the Grishman technic, has been described in 135 normal children, aged two through fourteen years. The normal patterns in all three planes are very specific. Minor variations of the normal are many, but seems to be easily recognized as such and put into the framework of the normal. Qualitatively, there appears to be no significant difference in the vectorcardiograms of these older children from those of adults.

The vectorcardiogram in anterior myocardial infarction. III

Abstract 1. 1. The planar vectorcardiograms obtained from thirty-five patients with anteroseptal and/or localized mid-anterior myocardial infarction were described and measurements of the QRS and T loops were made. 2. 2. Anterior wall infarction results in a new orientation of the initial and early vectors of the QRSsE loop in a posterior and inferior direction. This new orientation produces characteristic abnormalities which are clearly evident in the horizontal planar projection. 3. 3. Although the general morphology and measurement of the sagittal and frontal planar projections suggest left ventricular hypertrophy, the irregularities of contour in the early part of the loop corresponding to those mentioned in (2) make possible the differentiation between left ventricular hypertrophy and anterior myocardial infarction. In addition, these several features permit the combined diagnosis of left ventricular hypertrophy and anterior myocardial infarction to be made. 4. 4. Diagnostic features in the horizontal plane loops were present in all but three of thirty-five cases. However, the frontal plane loops in the exceptions disclosed abnormally large initial vectors diagnostic of localized infarction high on the anteroseptal or anterior wall. 5. 5. The S-T junction (J) is always oriented to the right and, usually, anteriorly. The TsE loop is oriented to the extreme right, slightly anteriorly, and inferiorly; and is often inscribed in a direction opposite to the QRSsE loop.