ABSTRACT
The genetic knowledge of parents of children with congenital heart disease, who had received genetic counseling, was compared with that of a control noncounseled group attending the same cardiac clinic. A follow-up questionnaire showed that both groups had excellent knowledge of the nature of their children's heart lesions. The counseled group had significantly more accurate knowledge of their recurrence risks. Inasmuch as the reproductive attitudes of some of these parents were found to be influenced by genetic information, parents of children with CHD should be given a better understanding of recurrence risks for CHD than many of them possess.
PIP: Parents of a group of children with congenital heart disease attendi ng the Yale-New Haven Pediatric Clinic were given genetic counseling which included an explanation of the genetic basis for their child's cardiac lesion and the risk of probable recurrence. This group was questioned 6 months later and compared to a control group of parents which did not receive the genetic counseling lecture. There was a highly significant (at the p less than .005 level) difference in genetic knowledge and knowledge of recurrence risk between the counseled and the control group. This type of counseling is recommended for parents of children with congenital heart disease.
Subject(s)
Genetic Counseling , Heart Defects, Congenital/genetics , Attitude to Health , Female , Humans , Male , Parents , Reproduction , RiskABSTRACT
Inotropic responses to digoxin (0.08 mg/kg) were studied in dogs and compared with responses during hypoxemia and autonomic blockade. Changes in left ventricular contractility (VC) were assessed by constructing function curves relating left ventricular (dP/dt)max and stroke volume to end-diastolic pressure. Augmentation of VC was observed 20 min after digoxin infusion and continued to increase until termination of the experiment after 60 min. In animals subjected to autonomic blockade with practolol, TEAC, and atropine, the increases in VC after digoxin were substantially greater. Equally large increases occurred in blocked dogs during sustained hypoxia (Pao2 = 28 mmHg). However, in animals without blockade there was a progressive fall in VC during hypoxia despite digoxin infusion, although less than in those not given digoxin. Serum digoxin levels were measured by radioimmunoassay and did not differ significantly in blocked compared to unblocked dogs or in hypoxic compared to nonhypoxic animals. These findings indicate that digoxin protects the heart from the decrease in myocardial contractility which occurs during extended hypoxia. This protective effect is more pronounced in animals deprived of autonomic function, possibly reflecting the elimination of reflex sympathetic withdrawal ordinarily induced by digitalis.
