Catecholamine-induced ductus arteriosus constriction in children

Ontogeny of chicken ductus arteriosus response to oxygen and vasoconstrictors

The present study aimed to characterize the contractile reactivity of the chicken ductus arteriosus (DA) from the last stage of prenatal development and throughout the perinatal period. Isolated DA rings from 15-day, noninternally-pipped 19-day, and externally-pipped 21-day embryos were studied using myograph techniques. On embryonic day 15, the chicken DA did not respond to O(2) (0 to 21%), norepinephrine (NE), or phenylephrine (Phe) but contracted in response to high-K(+) solution, the inhibitor of voltage-gated channels 4-aminopyridine, U-46619, and endothelin (ET)-1. These responses increased with advancing incubation age. Contractile responses to O(2), NE, and Phe were present in the 19- and 21-day embryo. Oxygen-induced contraction was restricted to the pulmonary side of the DA and was augmented by the nitric oxide synthase inhibitor N(omega)-nitro-l-arginine methyl ester and the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one and reduced by the peptidic ET(A) and ET(B)-receptor antagonist PD-142,893. Transmural electrical stimulation of nerves, the nonselective cyclooxygenase (COX) inhibitor indomethacin, the COX-1 inhibitor valeryl salicylate, the COX-2 inhibitor nimesulide, the inhibitor of ATP-sensitive K(+) channels glibenclamide, and the inhibitor of Ca(2+)-activated K(+) channels tetraethylammonium did not cause contraction of the DA rings at any age. We conclude that transition to ex ovo life is accompanied by dramatic changes in chicken DA reactivity. At 0.7 incubation, excitation-contraction and pharmacomechanical coupling for several contractile agonists are already present, whereas the constrictor effects of O(2) and cathecolamines appear later in development and are located in the pulmonary side of the DA.

Reactivity of the ductus arteriosus: Implications for transcatheter therapy

We report our experience in a 13-month-old boy undergoing transcatheter coil occlusion of a patent ductus arteriosus. Constriction of the ductus arteriosus with subsequent relaxation resulted in inadvertent coil embolization. This case report and review of the literature have implications for transcatheter treatment of persistent ductus arteriosus.

Epinephrine-induced constriction of the persistent ductus arteriosus and its relation to distensibility

The aim of this study was to investigate whether distensibility of the persistent ductus arteriosus (PDA) might predict its potential for vasoconstriction. Epinephrine-induced constriction and stretching were investigated in 10 patients with PDA. Age, sex, ductus type, its minimal diameter, its stretched minimal diameter, and its stretch index were compared between epinephrine responders and non-responders. Age, sex, weight or the configuration or size of the PDA did not predict stretchability. The stretch index was significantly greater in responders (1.7-2.0, 1.8+/-0.1) than in non-responders (1.3-1.7, 1.4+/-0.2, p<0.01). Stretching of the PDA may depend on the elasticity of the vascular wall, which in turn is determined by preservation of vascular smooth muscle.