Citations

The cardiovascular response to angiographic contrast medium was studied in 28 patients undergoing diagnostic angiocardiography under anesthesia. A transient phase of hypotension and tachycardia similar to that described by other authors was noted. Cardiac output was increased initially by 50 per cent and returned to the base line in 20 minutes. Peripheral blood flow increased by 100 per cent, apparently due to the direct effect of the hyperosmotic solution on the vascular smooth muscle. Hemodilution, maximal 2 to 4 minutes after injection of contrast medium, suggested a transient increase in circulating blood volume. Increased ventricular filling pressures, which were thought to be due to hypervolemia, were associated with increased left ventricular stroke work.

The analysis and description of the preoperative and postoperative vectorcardiograms in tetralogy of Fallot are presented. The spatial orientation of the maximum QRS vectors to the right, anteriorly, and inferiorly in group I is indicative of right ventricular hypertrophy. In group II patients, the vectorcardiogram showed evidence of increased electrical activity of the left ventricle. Vectorcardiographic patterns of complete right bundle-branch block were noted in nine patients in group III.

Left heart volumes were determined angiographically in 50 subjects of whom 18 had no abnormality of the left heart, 12 had lesions causing pressure overload of the left ventricle, and 20 had lesions causing volume overload of the left ventricle. The left heart volumes were in the normal range in the presence of pressure overload, but, with volume overload, end-diastolic, end-systolic, and atrial volumes were in excess of normal. A linear relationship was demonstrated between end-diastolic and end-systolic volumes, regardless of the pressure load on the ventricle. Thus, for all but one of the cases studied, total left ventricular ejection volume formed a nearly constant proportion of end-diastolic volume.

A case is reported of a man who had an acute painless dissecting hematoma of the aorta, which was diagnosed clinically in the absence of hypertension or known precipitating cause. The successful surgical treatment is described and illustrated. The following diagnostic features were stressed in the absence of pain: sudden onset of symptoms, syncope, acute peripheral arterial occlusion, appearance of aortic insufficiency, and finding of bruits over the course of the aorta. The significance of the symptom of pain in the torso and the possible modes of its production in this condition are considered, and it is suggested that pain in dissecting aneurysm may imply a poor prognosis.

Eighteen cases of stenosis of the branches of the pulmonary artery, seen at the Mayo Clinic, have been reviewed and subdivided into two main types: Type I, stenosis of the main branches of the pulmonary artery, 11 cases, and type II, stenosis of multiple peripheral branches of the pulmonary arteries, seven cases. Of special interest were two cases in which thrombosis occurred as a complication and one case in which surgical relief of multiple areas of stenosis in the peripheral branches of the pulmonary arteries was accomplished. Unexplained pulmonary hypertension necessitates further investigation, which includes cardiac catheterization for measurement of intracardiac pressure and frequently selective angiocardiography. Main branch or peripheral pulmonary artery stenosis should be suspected when a continuous murmur is heard or when poststenotic dilatations of the pulmonary artery branches or areas of decreased pulmonary vasculature can be perceived in the roentgenogram. Angiocardiography is the only technic that permits detailed anatomic evaluation of the entire pulmonary vasculature, especially in the cases associated with severe infundibular or valvular pulmonic stenosis. Stenosis of the branches of the pulmonary artery must be taken into account, when surgical repair of associated cardiovascular defects is considered. These lesions also might complicate anastomotic procedures involving the pulmonary artery in cyanotic patients.

Hemodynamic studies were made 2 weeks after repair of tetralogy of Fallot in 18 cases and 2 months to 6 years after operation in 5 cases. Intracardiac and intravascular pressures, oxygen uptake, arteriovenous oxygen content difference, cardiac output, heart rate, stroke index, and pulmonary and systemic resistance were measured. Residual intracardiac shunts and residual pulmonary stenosis and incompetence were assessed. Results were compared with similar studies on postoperative days 1, 2, and 3. Further insight into patterns of convalescence as well as into the favorable hemodynamic state usually pertaining after repair are provided by these data.

Clinical, hemodynamic, and angiocardiographic findings are described in seven cases of congenital mitral insufficiency. The volumes and changes in volume of the left atrium and left ventricle were calculated from the angiocardiograms and were found to be increased above the range of normal. Left ventricular stroke volumes thus obtained were compared with forward flows calculated from indicatordilution curves in order to quantitate regurgitant flow. Regurgitant flows varied between 19 and 94 per cent of the total left ventricular ejection volume, and forward flow was maintained as a result of a considerable increase in left ventricular volume. The left ventricular ejection volume was 50 to 64 per cent of the end-diastolic volume.

The clinical features and follow-up data on 107 patients who had a clinical diagnosis of aneurysm of the thoracic aorta made at the Mayo Clinic in the period 1945 through 1955 were reviewed. The ratio of male to female was 2.8 to 1, and the average age at the time of diagnosis was 59.3 years. Fusiform aneurysms were four times as frequent as saccular aneurysms; the most common location of the former was the descending thoracic aorta and of the latter the ascending thoracic aorta. Most of the aneurysms (73 per cent) were probably arteriosclerotic in origin. Symptoms, usually pain, and physical signs were present in a minority of patients and indicated a large aneurysm with a poor prognosis. Diastolic hypertension was present in almost half of the patients at the time of diagnosis and had an adverse effect on the patient's survival. Associated arteriosclerotic cardiovascular disease was present in 40 (37 per cent) of the patients at the time of diagnosis; some of these patients had multiple associated cardiovascular lesions. The presence of associated coronary, cerebral, or other peripheral arterial occlusive or aneurysmal disease had the most deleterious effect on survival. The prognosis for patients with large aneurysms was poorer than for those with small aneurysms. Information as to the cause of death was available in 59 (83 per cent) of the 71 patients known to be dead at the time of follow-up. Approximately a third of the deaths were due to rupture of the thoracic aortic aneurysm, and approximately a half, to associated cardiovascular disease, particularly that due to arteriosclerosis. It is believed that this study of patients with untreated aneurysms of the thoracic aorta may be used as a guide to the selection of patients with aneurysm for surgical treatment and may serve as a basis for evaluating the long-term results of such treatment.

The syndrome of erythermalgia is characterized by a burning distress of the extremities that is accompanied by redness and increased temperature of the skin. These symptoms are initiated or exacerbated by an increase in environmental temperature and diminished by measures that cool the skin. Of 51 patients with this clinical syndrome seen at the Mayo Clinic during the years 1951 to 1960 inclusive, 30 were considered as having primary erythermalgia because of the absence of demonstrable associated conditions, and the rest were classified as having secondary erythermalgia because the condition was associated with various diseases. Particularly significant was the relation of erythermalgia to the myeloproliferative disorders as evidenced in 10 cases. In some of these cases, erythermalgia preceded other manifestations of the myeloproliferative disorder by as long as 12 years. The primary type was found to occur in younger individuals and to be more often bilateral, to produce pain of greater intensity, and to involve larger areas of the affected extremities. The pathologic physiology of this syndrome remains unknown.