ABSTRACTS

changes in dp/dt of aortic pressure (Ao) could be re- lated to changes in LV dp/dt. LV and Ao dp/dt were measured in 27 patients in shock during treatment with norepinephrine (NE), isoproterenol (ISP) , dopamine (Dop) or low molecular weight dextran (LMWD) (Ta- ble I).

Changes in Ao dp/dt accurately reflected changes in LV dp/dt during tifusion of NE, ISP or Dop. Small in- creases in Ao dp/dt occurred after LMWD, were not accompanied by similar changes in LV dp/dt and may have been related to changes in intravascular volume.

TABLE I

Data for 27 Patients in Shock

Percent Increase (Mean * SEM) LV dp/dt Ao dp/dt

NE a2 f la ai =t ia

ISP 84 f 23 90+ 26

Dop 61 f 13 65 + 14 LMWD 4f 3 16f 4

NS = Not significant.

Significance

NS NS NS

P <O.OOl

Clinical and Morphologic Correlations in 259 Patients with Valvular Heart Disease

DONALD E. LOEW, MD: LAURENCE B. ELLIS, MD, FACC, Boston, Massachusetts

Clinicopathologic correlations have been made of the hearts of 259 patients with valvular heart disease who died after open heart surgery. The studies were de- signed to determine the prevalence of undiagnosed val- vular involvement and the prevalence of coronary ar- tery disease (CAD) and angina without aortic (AVD) or mitral valve disease (MVD). In 81 patients diag- nosed clinically as having isolated MVD, aortic valvular lesions were found at postmortem examination in 28 (38%) ; but in only 1 was the lesion estimated to be hemodynamically significant. In contrast, in 115 pa- tients with clinically isolated AVD, postmortem study revealed mitral valve involvement in 73 (65%) ; in 13 (11%) the involvement was hemodynamically signifi- cant. The percentage of missed diagnoses was the same in patients who had had cardiac catheterization or an- giography, or both, as in those without these studies. Tricuspid valvular lesions were diagnosed clinically in 6 patients but were found at postmortem study in 55. Of the 7 estimated to be hemodynamically significant, 3 were recognized clinically.

The prevalence of CAD was not significantly differ- ent in patients with predominant AVD versus MVD. Angina pectoris occurred in 25 of 54 patients with pre- dominant AVD who had O-l + CAD (41%), and in 20 of 25 with 2-3 + CAD (80%). None of the 39 with pre- dominant MVD who had O-l I- CAD had angina pec- toris ; 5 of 16 with 2-3 + CAD had angina (31%). The age distribution of the 2 groups was the same; 72% of patients with AVD and 33% with MVD were male. This study provides information that may stimulate clinical evaluation of patients with valvular heart dis- ease.

Pharmacodynamic Applications of L-Dopa for the Treatment of Cardiogenic Shock

JOSE LOZANO, MD; HUGO CARRASCO, MD; TZU-WANG LANG, MD, FACC; ELIOT CORDAY, MD, FACC, Los Angeles, California

Experiments were designed to determine basic phar- macologic effects that might be applied to the treat- ment of cardiogenic shock.

Cardiogenic shock was induced by serial ligation of the branches of the left circumflex coronary artery in 8 dogs. Simultaneous electromagnetic flow measure- ments were made from the ascending aorta, left an- terior descending (LAD) coronary, carotid, renal and mesenteric arteries, along with pressure tracings of the right atrium, aorta, left ventricle and the rate of rise of left ventricular (LV) (dp/dt),,,,,. When the systolic pressure remained below 80 mm Hg for 30 minutes, L- Dopa was infused at a constant rate of 300 p/kg per min. Data were compared during normotensive control,, shock state and while L-Dopa was administered for a 60 minute period.

The beneficial effects of L-Dopa usually began 15 to 30 minutes after intravenous infusion, when it was noted that mean aortic pressure increased to 92%, coronary flow to 171.1% (P <0.02) and LV (dp/dt),,, to 186.376 (P <O.OOl) of the control values. These ef- fects were maintained as long as the infusion continued and persisted for an average of 20 minutes after the intraven’ous drip was stopped. Improved hemodynamics suggest the shock state was reversed.

We noted L-Dopa affected both alpha and beta recep- tors, and its beneficial effects could be eliminated by specific alpha or beta blockade. Beta blockade reduced coronary flow without altering blood pressure; alpha blockade reduced pressure, and the coronary flow dropped proportionally.

Two-Stage Palliative Surgical Approach for Pulmonary Atresia (Type I)

E. F. LUCKSTEAD, MD; LEONE MATTIOLI, MD; IVAN K. CROSBY, MB, BS; WILLIAM A. REED, MD, FACC; ANTONI M. DIEHL, MD, FACC, Kansas City, Kansas

Thirteen infants with a diagnosis of pulmonary atresia type 1 (Greenwold) proved angiographically or at au- topsy, or both, were treated by various surgical proce- dures. Five infants underwent palliation with shunt procedures alone, and all died within 2 months, except for 1 (K.E.) who had an associated atria1 septal defect and patent ductus arteriosus. The interatrial communi- cation was small in ail 6 of the autopsy cases. Recently, 5 of the 13 patients were treated by combined Waters- ton-Cooley and Blalock-Hanlon procedures ; all survived with excellent palliation.

Pulmonary valvotomy was performed successfully in 5 patients; 3 of these had previous combined Blalock- Hanlon and Waterston-Cooley procedures followed by pulmonary valvotomy at 4, 4 and 8 months of age, re- spectively. Two had no surgical palliation since an atria1 septal defect and patent ductus arteriosus coexisted, and pulmonary valvotomy was performed at 9 days and

646 The American Journal of CARDIOLOGY