Contractile reserve of valvular heart diseases echocardiographically evaluated by epinephrine loading before and after cardiac surgery.
In order to evaluate cardiac contractile reserve, echocardiographic studies were performed on 59 patients with acquired valvular heart disease and 13 patients with atrial septal defect. After epinephrine loading, the 59 patients were classified into three groups. In group I, echocardiographically-obtained left ventricular posterior wall excursion (PWE) remained below 10 mm after the administration of 2 microgram/min epinephrine. This group included patients with PWE below 10 mm after 1 microgram/min epinephrine loading but who could not endure the 2 microgram/min infusion because of significant adverse effects. In group II, PWE was less than 10 mm before the loading, but exceeded 10 mm after the administration of 1 or 2 microgram/min epinephrine loading. In group III, PWE exceeded 10 mm without stress. The conclusions derived from our data are as follows: The PWE and mean left ventricular posterior wall velocity (mPWV) obtained by echocardiography reflect the stroke volume derived from the thermodilution technique. It is possible to estimate the cardiac contractile force in patients who have a paradoxical motion of the interventricular septum, in the preoperative and even in the early postoperative periods. Patients whose PWE and mPWV are less than 10 mm and 35 mm/sec, respectively, after 2 microgram/min loading of epinephrine (group I), are likely to have severe cardiac failure after surgery. Inotropic stimulation is considered to be a very useful indicator for prediction of cardiac contractile reserve. Patients having decreased PWE, mPWV, mVcf and EF before surgery may have arrested recovery in both short- or long-term follow-up. However, surgical treatment is recommended for these patients with low cardiac function, because some improvement can be expected after surgery.