Computerized tomography in the diagnosis of abdominal aortic aneurysms.

Computerized tomography allows good definition of the retroperitoneal space, especially the abdominal aorta. During a 15 month interval, 30 patients with pulsatile, abdominal masses were evaluated by computerized tomography to determine the presence of an aortic aneurysm, 4 centimeters or greater in size. Twenty-one of the 30 patients were found to have an aneurysm. In patients with a normal aorta, information concerning another disease process was often obtained. Results of computerized tomography were then compared with the other diagnostic techniques available and, in certain instances, with the size of the aneurysm at operation. Computerized tomography is the most accurate means of evaluating abdominal aortic aneurysms. The ability to detect a retroperitoneal space hemorrhage and to assess the pathologic condition of other abdominal viscera are two additional advantages.

Pathophysiologic significance of S-T and T wave abnormalities in patients with the intermediate coronary syndrome.

The frequent association of new ST-T wave changes without Q waves in the surface electrocardiogram of patients with the intermediate coronary syndrome necessitates a better understanding of the pathophysiologic significance of this finding. A previous study in patients with stable coronary artery disease indicated that the surface electrocardiogram is insensitive in detecting epicardial Q waves. This relation was evaluated in 21 patients with the intermediate syndrome, characterized by recurrent chest pain at rest associated with significant new S-T or T wave abnormalities, or both, and no new Q waves in the surface electrocardiogram at the time of open heart coronary bypass surgery. Unipolar electrograms were recorded from the epicardial surface of the left ventricle before the bypass procedure. In 19 patients, epicardial electrograms revealed initial R waves over areas of the left ventricle in which the acute S-T and T wave abnormalities were evident in the surface electrocardiogram. Two patients had epicardial Q waves (one laterally and one inferiorly). In seven patients, a transmural biopsy specimen was also obtained from the ischemic area. All showed histologically normal myocardium without evidence of early inflammatory or necrotic tissue. Of the 19 patients discharged, only one demonstrated new postoperative Q waves that had been detected by epicardial recordings before bypass. In summary, patients with the intermediate syndrome exhibiting S-T or T wave abnormalities, or both without new Q waves in the surface electrocardiogram generally do not have Q waves either in the intraoperative epicardial or postoperative surface electrocardiogram. In addition, no histopathologic abnormalities are apparent in biopsy specimens taken from the ischemic area.

Local characteristics of the normal and asynergic left ventricle in man.

The significance of ventricular asynergy in determining medical prognosis and surgical risk in patients with coronary artery disease and its delineation by ventriculography have been of increasing interest. To determine the underlying histopathologic and electrographic features of left ventricular asynergy, 39 patients undergoing open heart surgery were studied. Thirty-six histopathologic specimens were obtained in 31 patients (26 as transmural needle biopsies and 10 as aneurysm resections). In four normally contracting areas and 12 hypokinetic areas, neither fibrosis nor early changes of myocardial damage was evident. In contrast, of eight akinetic areas there was more than 50 per cent muscle loss in four and from 30 to 35 per cent muscle loss in three, in only one area was there less than 10 per cent muscle loss. Of 12 dyskinetic zones there was more than 75 per cent muscle loss in 10 zones, 35 per cent in one and no pathologic abnormalities in one. Epicardial electrograms were obtained from 35 areas in 29 patients. Of 10 normally contracting ventricles, in one, pathologic Q waves were demonstrated only over the inferior area. Progressive increases in the severity of asynergy were associated with a progressive increase in frequency of initial abnormal Q waves. In only one of nine hypokinetic areas were epicardial Q waves exhibited, but they were present in six of 10 akinetic and five of six dyskinetic areas. Both histopathologic and electrographic data were available from 20 asynergic areas in 16 patients. Initial epicardial R waves were associated with normal biopsy specimens in seven of eight hypokinetic areas. Of seven akinetic areas, initial R waves were associated with 30 to 35 per cent muscle loss in three; of four areas with initial Q waves, there was a 35 per cent muscle loss in one and more than 50 per cent muscle loss in three. Similarly, of five dyskinetic segments, a QS pattern was associated with more than 75 per cent fibrosis in four. In one dyskinetic area there was an intial R wave in association with a normal appearing biopsy specimen. In summary, a good correlation exists between the severity of asynergy by ventriculography, the degree of muscle loss and the presence of epicardial Q waves. However, a significant amount of histologically and electrographically normal myocardium may be present even in severely asynergic areas.

Correlation of pathologic Q waves on the standard electrocardiogram and the epicardial electrogram of the human heart.

To evaluate the relationship between abnormal Q waves on the standard ECG and localized ventricular excitation, unipolar epicardial electrograms were recorded over the left ventricle during aortocoronary bypass surgery in 36 patients. Of 20 without standard ECG Q waves, six had abnormal epicardial Q waves, three anterioly and three inferiorly. Of 16 patients with standard ECG Q waves, four had both precordial and anterior epicardial Q waves while seven had Q waves in leads III and aVF and inferior epicardial Q waves. Three of the 14 had Q waves in both precordial and inferior leads of the ECG but epicardial Q waves only from the antero-apical region in two and only from the inferior wall in one. Two patients with Q waves in both III and aVF had no epicardial Q waves. Thus, the standard electocardiogram underestimates epicardial Q waves. If Q waves are present in the standard ECG, they correlate with the presence, although not invariably the location of Q waves on the epicardial electrogram.

Anomaly of the aortic arch: a case report.

A case of the anomaly of the aortic arch was presented. The case showed subclavian steal syndrome due to the hypoplastic left subclavian artery associated with the double aortic arch with the obliterated left aortic arch. The hypoplastic left subclavian artery was replaced with the Dacron tube graft and the obliterated left arch was divided. Subclavian steal disappeared and the patient is in good condition at the present time.

Reversible asynergy. Histopathologic and electrographic correlations in patients with coronary artery disease.

Histopathologic-electrographic studies of ventriculography depicted nitroglycerin responsive and unresponsive asynergic areas were performed in 25 patients. Of 29 areas, 12 improved with nitroglycerin, showing less than 10% muscle loss. Seventeen unimproved zones demonstrated significant fibrosis. Epicardial electrograms showed R waves in eight of nine improved zones. Of 11 unimproved zones, eight had Q waves. Histopathologic-electrographic data from five responders showed less than 10% muscle loss, of whom four had epicardial R waves. Six unresponsive areas had significant fibrosis, with a QS over four. Thus, nitroglycerin responsive asynergic areas are generally comprised of histologically intact myocardium and are associated with epicardial R waves.