Citations

Cardiac output and related variables were measured in patients after open intracardiac surgery. Factors affecting cardiac performance during this period were the original anatomic lesions, the details of the operative procedure, ventricular-outflow resistance, transfusion of blood, the stage of convalescence, and digitalis. In postoperative patients, metabolic rate, level of hemoglobin, and level of oxygen in arterial blood varied more widely and acutely than in nonsurgical patients, resulting in a less predictable relation between cardiac output and oxygen saturation of mixed venous blood. Therapeutic applications of these observations were discussed.

Physiologic studies have been carried out during the first 3 days after intracardiac repair of tetralogy of Fallot. All patients survived. The ratio between systolic pressure in right ventricle and a systemic artery was 0.7 or less in all cases and did not vary significantly during the period of study. Residual left-to-right shunts of moderate degree were demonstrated in three patients (repaired with Teflon prostheses). In one of these three, no definite evidence of shunt could be found 2 weeks after operation. Additional abnormal circulatory pathways exist in these patients. Clear evidence was obtained of left-to-right shunting through aorticopulmonary collateral connections in one case. Systemic index was usually below normal or in the low normal range. It was usually lower on the second and third postoperative days than on the first postoperative day. Left atrial pressure was sometimes strikingly higher than right atrial pressure 30 minutes after repair, but not thereafter. Pulmonary vascular resistance was normal or slightly elevated. Gas exchange and management were adequate to maintain normal or near normal oxygen and carbon dioxide levels in arterial blood. Mild metabolic acidosis existed on the first 2 days, but had generally cleared by the third day. The implications of these data are discussed relative to ventricular function and performance, adequacy and technic of surgical repair, administration of blood after operation, and the state of preparedness in the lung and left ventricle in patients with tetralogy of Fallot.

Sixteen patients were studied immediately and for 3 days following surgical closure of ventricular septal defect. In eight patients with absent or mild pulmonary vascular disease, convalescence was uneventful and only small deviations from normal in cardiac output, blood gas levels, and acid-base profile were observed. The remaining eight patients had pre-existing moderate or severe pulmonary vascular disease. Values for cardiac output were abnormally low at some time in the postoperative period in all but two of these eight patients. Failure to survive was clearly related to a low cardiac output in four of the five nonsurvivors. Reduction in cardiac output observed in this group of patients is believed to be based in major part on the pre-existing increased resistance to blood flow through the pulmonary vascular bed and also to impaired right ventricular function following operation. No evidence was obtained to suggest that major changes in pulmonary vascular resistance occurred in the immediate postoperative period in patients with moderate or severe pulmonary vascular disease following closure of ventricular septal defect. Right ventricular function following atriotomy or transverse ventriculotomy was less impaired than after vertical ventriculotomy.

Physiologic observations were made on eight patients following repair of atrial septal defect or total anomalous pulmonary venous connection. A pattern of changes in cardiac output and atrial pressures during the first 3 postoperative days was noted. Cardiac output was abnormally low in some patients with obstructive pulmonary vascular disease or low atrial pressures. Transfusion of whole blood was effective in elevating cardiac output in the operating room and after operation. Left atrial pressure was higher than right atrial pressure in the operating room. Postoperatively left and right atrial pressures tended to become equal in some patients, and the levels were slightly elevated. Heart rate did not seem to be directly related to cardiac output. Ventilation was adequate with regard to elimination of carbon dioxide. Arterial oxygen saturation was maintained at 93 per cent or more by the use of oxygen-enriched mixtures. The difference in arteriovenous oxygen content was inversely related to cardiac output. Acidemia was present 2 to 4 hours after operation, but in general the pH of arterial blood had returned to normal by day 2. Some mechanisms possibly related to the observations are discussed.

Among 13,314 necropsies following death from neoplastic and nonneoplastic diseases performed at the Mayo Clinic from 1942 through 1958, 189 cases of secondary malignant lesions of the pericardium were demonstrated, an incidence of 1.42 per cent. Carcinoma of the lung and breast, the lymphomas, and leukemia constituted the large majority of the primary malignant lesions that caused the pericardial metastasis. Fifty-five of the 189 patients were adjudged to have had some impairment of cardiac function as a consequence of the pericardial metastasis and the following conclusions concern this group. 1. In 47 patients (86 per cent), the lesions were either the immediate or a contributory cause of death. 2. The most common mechanism whereby metastatic lesions in the pericardium interfered with cardiac function was by the development of pericardial effusion. Next in frequency was effusion combined with myocardial invasion and then cardiac constriction by tumor. Combinations of these processes with malignant encroachment on the great vessels and with invasion of coronary veins were the other mechanisms noted. Involvement of coronary arteries and the cardiac nerve supply was not noted. 3. Pericardial fluid was significant in causing tamponade in 31 cases. The fluid was frankly hemorrhagic in a small minority of these cases although fibrinous pericarditis was present in 45 (82 per cent) of the group. Pleural effusion was present in 48 (92 per cent) of 52 cases and was usually bilateral. Ascites was present in 22 (50 per cent) of 44 cases; the quantity was usually rather small. 4. Only one patient had metastasis to the pericardium without metastasis to other thoracic structures; exclusive of patients with leukemia, 43 (92 per cent) of 47 patients had extrathoracic metastatic lesions. 5. Dyspnea, cough, pleural effusion, hepatomegaly, and thoracic pain were the most commonly recorded signs and symptoms that might be related to the pericardial lesions. However, more specific signs and symptoms directing attention to pericardial or cardiac involvement were not commonly recorded. 6. The diagnosis of pericardial metastatic disease was suspected or established in only 16 (29 per cent) of the 55 patients, although 34 (62 per cent) either received treatment for congestive heart failure or were given roentgen therapy to mediastinal structures. 7. Of the 27 patients whose electrocardiograms were available, 25 had T-wave abnormalities, 22 had low QRS voltage, and 15 showed sinus tachycardia. 8. Thoracic roentgenograms, made on 53 patients, supplied clues to the diagnosis of pericardial malignancy in 28.

The high rate of necropsy in deaths among permanent residents of Rochester, Minnesota, provided a unique opportunity to study the prevalence of coronary heart disease and the frequency and mode of death resulting from this disease. In this community of approximately 30,000 population, necropsy was done in 73 per cent of all resident deaths during the years 1947 through 1952. Included in this group were 691 necropsies that represented 67 per cent of the 1,026 deaths of persons 20 years of age or older. Coronary heart disease caused death in 221 patients (23 per cent of all necropsies and 32 per cent of all necropsies on adults). These 221 coronary deaths in adults represented 41 per cent of the men and 22 per cent of the women. The coronary deaths were attributed to acute coronary failure (sudden death) in 94 patients (43 per cent), acute myocardial infarction in 87 patients (39 per cent), congestive heart failure in 32 patients (14 per cent) and thromboembolism in eight patients (4 per cent). The 87 patients dying during acute myocardial infarction died of congestive heart failure (30 per cent), myocardial rupture (24 per cent), acute coronary failure (23 per cent), and thromboembolism (14 per cent), with the remaining 9 per cent dying of a combination of acute myocardial infarction and additional serious systemic disease. The greatest number of deaths from coronary heart disease occurred during the seventh decade of life in men and the eighth decade in women. At least one coronary artery exhibited from 25 to 100 per cent obstruction from atherosclerosis in 513 hearts (74 per cent of the adult necropsies). These necropsies, representing two thirds of all deaths in adults in this community, disclosed that significant coronary-artery disease was present in three of four adults and was the cause of death in four of 10 men and two of 10 women.

A group of 26 patients who had peripheral occlusive arterial disease of the lower extremity were studied before and after chemical or surgical unilateral lumbar sympathectomy. The temperatures of the gastrocnemius muscle and of the skin of the sural area were determined simultaneously preoperatively and postoperatively. Only patients who had undergone successful unilateral lumbar sympathetic denervation based on the postoperative area of anhidrosis were included. The data were obtained under basal conditions among the 26 patients, and the persons studied were divided into two groups. Group 1 was composed of 17 patients (65 per cent) who had a definite parallel increase of 1.2 C. in the temperature of the gastrocnemius muscle and the skin after unilateral sympathectomy. In group 2 (nine patients or 35 per cent) the temperature of the gastrocnemius muscle and the skin of the sural area was unchanged after unilateral sympathectomy. Since none of these patients were suitable for surgical bypass arterial-grafting procedures and all were in the older age group, not too much could be expected from the standpoint of an increase in temperature. However, when the temperature of the skin after operation increased, the temperature of the gastrocnemius muscle also increased.

A case is reported of a 20-day-old infant with origin of the right pulmonary artery from the ascending aorta. Besides its abnormal origin, the artery was stenotic in its proximal half. We believe the malformation results from persistence of the distal (instead of the proximal) part of the primitive sixth aortic arch and of a portion of the right dorsal aorta. The presence of ductal tissue in the wall of the right pulmonary artery supports this concept. The pulmonary vasculature in the two lungs showed great differences in medial and intimal characteristics. A second case of origin of the right pulmonary artery from the aorta, deseribed elsewhere, provided material for comparative study of the structure of the right main pulmonary arteries and the intrapulmonary branches.