Edward F. Dunne

Disease of the left main coronary artery. Surgical treatment and long-term follow up in 267 patients.

Of 4,196 patients undergoing coronary angiography, 297 (7 percent) had left main coronary arterial narrowing. In 188 (4.5 percent) the narrowing was greater than or equal to 70 percent and in 109 (3 percent) it was between 50 and 69 percent. Three patients (1 percent) died at cardiac catheterization. Saphenous vein bypass graft surgery was performed in 267 patients with an operative mortality of 7 percent: in 179 patients the left main coronary narrowing was greater than or equal to 70 percent (operative mortality 9 percent), and in 88 between 50 and 69 percent (mortality rate 2 percent). There was an average of 2.6 grafts per patient. The course of these patients was followed up for 4 3/4 years. At 1 year there was a 92.2 percent survival rate. The rate of survival at 2, 3 and 4 3/4 years, was 91, 89 and 86 percent, respectively. After saphenous vein bypass graft surgery, 75 percent of patients are angina-free and 22.4 percent are in improved condition. Grafts were studied in 51 patients and 85 percent of 128 grafts were found to be patent. It appears that there is improvement in survival and a reduction of symptoms after saphenous vein bypass graft surgery in patients with left main coronary arterial narrowing.

Geometric and functional abnormalities of the left ventricle with a chronic localized noncontractile area.

Abstract Thirty-one patients with coronary artery disease, 25 of whom had a chronic localized noncontractile area in the anteroapical region of the left ventricle, were studied at rest by means of left heart catheterization, left cineventriculography and selective coronary arteriography. The left ventricular volume, stroke volume, ejection fraction, left ventricular end-diastolic pressure, cardiac output and the surface area of the noncontractile area were measured. The patients with a noncontractile area were classified in 4 groups according to the size of the noncontractile area relative to the end-diastolic left ventricular surface area. The relative size of the non-contractile area ranged from 5 to 47 percent. Six patients with uncomplicated coronary artery disease comprised the control group. The critical size of the noncontractile area beyond which significant functional derangement occurred appeared to be 20 to 30 percent of the left ventricular internal surface area. The end-diastolic volume increased significantly and the ejection fraction was reduced to less than half of normal when the regional noncontractile area was larger than the critical size. Neither the cardiac output nor the left ventricular end-diastolic pressure correlated closely with size of the noncontractile area. In contrast, the ejection fraction was a more sensitive indicator and correlated well with the extent of regional contraction abnormality. In this study, double vessel disease was most common, followed by single vessel disease. Obstruction of the left anterior descending coronary artery was significant in the formation of anteroapical noncontractile regions.

Left Ventricular Performance before and after Removal of the Noncontractile Area of the Left Ventricle and Revascularization of the Myocardium

The left ventricular volume and the internal surface areas of noncontractile regions were measured by cineangiocardiography at 60 frames/sec in nine patients with a chronic localized noncontractile area of the left ventricle. Arteriosclerotic heart disease was proven in eight patients by means of coronary arteriography. Left ventricular end-diastolic pressure, stroke volume, ejection fraction, mean circumferential shortening, and cardiac output were also measured before and after removal of the noncontractile area and revascularization of the myocardium.The noncontractile areas, measured at end-diastole, ranged from 12 to 40% of the internal surface area of the left ventricle. Generally, impairment of the left ventricular function depended on the size of the noncontractile areas. The end-diastolic volume was approximately 150 ml/m2 when the size of noncontractile areas exceeded 20-25% of the left ventricular surface area (r = +0.72; P < 0.05). The ejection fraction decreased as the size of the noncontractile areas increased (r = −0.81; P < 0.01). Following surgery, the left ventricular function, as well as the clinical condition, improved significantly, although the cardiac performance remained in the abnormal range in most patients. The ejection fraction increased (P < 0.05), and the percent circumferential shortening also improved (P < 0.05).Removal of the noncontractile area of the left ventricle and revascularization of the myocardium improved the cardiac performance and increased the sense of well being in these patients.

The electrical impedance cardiogram in health and disease

Abstract 1. 1. The electrical impedance cardiogram (ICG) records continuous changes in heart shape throughout the cardiac cycle. It can be recorded on any direct writing electrocardiograph. 2. 2. Certain electrical impedance cardiograms closely resembled mechanical displacement recordings of heart motion (apexcardiograms), indicating a related origin. 3. 3. Tracings from normal subjects resembled each other, but tracings from patients with known cardiac deformities differed from the normal. 4. 4. Atrial activity was recorded selectively. 5. 5. Paradoxical bulges of the left ventricle produced characteristic abnormalities in impedance cardiograms. 6. 6. The impedance cardiogram can be used to analyze dynamic dysfunctions of the heart.

Surgical Treatment of High Pressure Patent Ductus Arteriosus

Thirteen patients with high pressure patent ductus arteriosus were operated upon. There was no operative mortality in this group. Twelve patients have shown remarkable clinical improvement, and there was a decrease in the pulmonary arterial pressure at the time of recatheterization in 11 of these patients restudied. One patient developed severe pulmonary hypertension and died six and one-half years after operation.The pulmonary arterial systolic pressure dropped minimally in two patients, despite marked clinical improvement. Both patients had associated lesions: a large ventricular septal defect in one and severe congenital aortic stenosis in the other. Both patients are to be operated upon.All patients with a predominant left-to-right shunt and a patent ductus arteriosus should have division of the patent ductus arteriosus. If a concomitant lesion requiring open-heart operation, such as a ventricular septal defect or aortic stenosis, is present, it should be corrected at a later date.

Intracardiac foreign body simulating double-chamber right ventricle.

Abstract Initiated by the introduction of a wooden splinter into the heart at age 5 years, a continuous morphologic change of the right heart chambers and the tricuspid valve took place over a period of 54 years. Clinical and angiographic findings indicated a double-chambered right ventricle and tricuspid regurgitation caused by endocardial and myocardial fibrosis that eventually resulted in marked heart failure. The patient was operated on at age 59, the foreign body was removed from the right ventricular cavity, and the tricuspid valve was replaced with a prosthetic disc valve with a muscle guard. After this procedure, the patients condition improved significantly.