Davis, George D.

The use of roentgen videometry as a means of studying regional left ventricular wall dynamics and performance was evaluated in 32 patients undergoing coronary arteriography. Nine patients had normal coronary arteriograms and hemodynamic findings (group 1), 8 patients had generalized decrease in left ventricular contraction and abnormal hemodynamic findings (group 2), and 15 patients with coronary artery disease had regional wall dynamics abnormalities (group 3). Sixty-per-second determinations of wall thickness were performed in selected sites of the left ventricle. Measurements performed included end-diastolic wall thickness (EDTw), mean and peak rates of systolic wall thickening (m and p dTw/dt), and fractional systolic increase in wall thickness (ΔTw/EDTw). In patients with uniformly performing ventricles (groups 1 and 2), these parameters correlated well with other parameters of ventricular function. Best distinction between the "normal" group (group 1) and the "abnormal" group (group 2) was achieved when the rates of thickening (m and p dTw/dt) were utilized ( P < 0.001). In patients of group 3, three types of abnormal regional wall dynamics could be determined and quantified objectively: hypokinesia (decreased p dTw/dt), akinesia (p dTw/dt = 0), and dyskinesia (p dTw/dt < 0). The severity of the abnormality of the wall dynamics correlated well with the presence or absence of a previous infarction on the electrocardiogram, and the anatomic location was strongly correlated with the distribution and severity of coronary artery lesions within a given ventricle.

Six years have passed since the first successful surgical correction of truncus arteriosus. A review of our experience enables some conclusions regarding the operation. Patients with mild or moderate truncal valve incompetence do not need truncal valve replacement. Patients with severe truncal valve incompetence require valve replacement, which is associated with a significantly increased surgical mortality. The surgical mortality is not increased in hemodynamically favorable patients who have only one pulmonary artery. However, these patients are especially likely to have early development of severe pulmonary vascular disease. The surgical mortality for the patient with uncomplicated disease and two pulmonary arteries, with pulmonary resistance of less than 8.0 units m 2 , is 10%. In patients with pulmonary resistance between 8.0 and 12 units m 2 , the mortality is approximately three times greater. Patients with pulmonary resistances greater than 12.0 units m 2 are probably inoperable. Different hemodynamic criteria must be applied in assessing the operability of patients with a single pulmonary artery. A systemic arterial oxygen saturation less than 85% in a patient with two pulmonary arteries and without pulmonary artery stenosis or a pulmonary artery band usually indicates inoperability. Elective operation usually is deferred until a patient is four years old, but if the patient's clinical condition warrants, the procedure can be done at any time after the age of one year, with a good chance of success. Follow-up on most operated patients has been encouraging.