RESUMO
The authors describe the morphogenesis and functional alterations of the coronary arterial net in the ectopic coronary arteries: a) with origin in the aorta or its branches and b) with origin in the pulmonary artery. The coronary arteries are developed from: 1) endothelial sprouts localized in the great arteries walls at the level of the sigmoidal values, 2) right and left subepicardial vascular network and 3) the intramyocardial sinusoids. Most of the ectopic coronary arteries result from alterations in the connection between these three embryonic elements. The deviation of one of the subepicardial vascular network in a wrong way (in direction of pulmonary artery or the opposite Valsalva sinus) will stimulate the development of endothelial sprouts which will connect such network originating abnormal connections and anomalous origin of the coronary arteries. The origin of both coronary arteries from the pulmonary artery is in compatible with life. Myocardial ischemia is absent in patients with type I (infant) or type II (adult) anomalous origin of one coronary artery from the pulmonary artery, only in the transitional phase between both types (I and II) there is myocardial ischemia previous to the formation of the collateral coronary circulation. The ectopic origin of the coronary artery from the aortic Valsalva sinus have very little hemodynamic repercussion in the patient. Although there are cases with postexercise sudden dead. These anomalies associated to atherosclerotic coronary stenosis have an impact on the evolution and prognosis of ischemic heart disease.
Assuntos
Aorta , Coristoma/fisiopatologia , Doença das Coronárias/fisiopatologia , Anomalias dos Vasos Coronários/fisiopatologia , Artéria Pulmonar , Seio Aórtico , Adulto , Cateterismo Cardíaco , Coristoma/complicações , Coristoma/diagnóstico , Angiografia Coronária , Doença das Coronárias/complicações , Doença das Coronárias/diagnóstico , Anomalias dos Vasos Coronários/diagnóstico , Anomalias dos Vasos Coronários/etiologia , Feminino , Humanos , Recém-Nascido , Masculino , Pessoa de Meia-Idade , MorfogêneseRESUMO
In order to explain the congenital coronary arteries malformations, the authors review the recent concepts on the coronary artery morphogenesis, based in the findings that in the human embryo, these arteries evolve from three sources: 1) endothelial aortic buds, 2) cavitary cellular groups from pericardial origin and with angiogenic character, which migrate to the cardiac zones where the coronary arteries will be distributed, and 3) the intramyocardial sinusoids. The anatomic and histologic cardiac alterations will be reflected in modifications of the coronary artery pattern. The coronary artery fistulae are formed by the persistence of the sponge structure of the myocardial wall, present in the early ontogenic steps of the cardiac development; such fistulae alter the normal functions of the coronary vascular tree and are capable to cause angina pectoris to the patient through diverse mechanisms: absence of capillarization, steal phenomenon aggravated by the altered coronary arteries properties when aneurysm or vascular channels are developed. The authors suggest a classification of the congenital coronary arteries anomalies: I. Anomalous origin in the sinus of Valsalva (anomalous and ectopic origin), II. Malformations of the coronary branches (in number, distribution and wall anomalies) and III. Anomalous connection of the coronary arteries: fistulae and persistence of the intramyocardial sinusoids isolated or communicated to left and right ventricles. The latter are frequently associated with aortic or pulmonary valve atresia. They do not cause myocardial ischemia and are formed secondary to the intracavitary elevated pressure which maintained the persistence, dilatation and communication of the ventricular chambers with such sinusoids and coronary arteries in the case of pulmonary valve atresia and with coronary veins in the case of aortic valve atresia.
Assuntos
Anomalias dos Vasos Coronários/embriologia , Adolescente , Adulto , Idoso , Angina Pectoris/etiologia , Angiografia Digital , Criança , Angiografia Coronária , Anomalias dos Vasos Coronários/diagnóstico , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Recém-Nascido , MasculinoRESUMO
The congenital absence of the pulmonary valves is a rare malformation that mainly affects children, frequently is associated with other cardiac malformations and very rarely is present in adults. Elective or urgent surgery is indicated in the symptomatic child; on the other hand, surgical treatment in the asymptomatic adult with this anomaly is controversial. Based on the reported experience in the literature, in the present article, the authors discuss the therapeutic approach of an asymptomatic 22-year-old male with pulmonary valvular absence with practically no hemodynamic repercussion. Although there had been few reported cases of isolated pulmonary valvular absence, the authors concluded that surgery is not a satisfactory solution and that it might be postponed to the time that patients develop congestive heart failure and or respiratory insufficiency. In order to detect that on time, we recommend a follow up based on periodic echocardiographic studies.