Which of the following is true about patent ductus arteriosus?
Ans. is 'a' i.e., Indomethacin is used in medical management Patent ductus arteriosuso Patent ductus arteriosus is a communication between the pulmonary artery and aorta. The ductus arteriosus is present in fetal life which connects pulmonary trunk to aorta. It closes functionally and anatomically soon after birth.o 'Functional closure1 takes place within 15 hours of birth. rAnatomic closure' of ductus arteriosus occurs 10-21 days after birth.o Prostaglandins maintain the patency of ductus. The persistence of function of ductus arteriosus beyond 24 hours after birth is considered as PDA in term neonate, i.e. if functional closure does not take place in 24 hours after birth, it is considered as PDA.o The aortic attachment of ductus arteriosus is just distal to subclavian artery. PDA is more common in females than in males.Hemodynamics of PDAo In PDA blood flows from aorta to pulmonary artery because aortic pressure is higher than pulmonary artery pressure - Left to right shunt.o Pressure gradient between aorta and pulmonary artery is maintained throughout the cardiac cycle (during systole and diastole) - Continous murmur, i.e., murmur starts in systole after S1 and reaches a peak at S2. It then diminishes and audible only a part of diastole.o Larger blood volume passes through pulmonary circulation (blood from right side of heart plus some blood from aorta) - Pulmonary plethora which may cause pulmonary hypertension,o Increased flow after passing through lung reaches the left atrium and causes volume overload - Left atrial dilatation and hypertrophy.o Increased blood volume passes from left atrium to left ventricle through mitral valve, i.e., increased flow through mitral valve - Accentuation of SI and delayed diastolic murmur.o Left ventricle recieves larger amount of blood that results in volume overload. Left ventricle enlargemento Extra volume passes through aortic area cause delayed closure of aortic valve which may close even after pulmonary valve (normal pulmonary valves close after aortic valves). - Paradoxical spliting of S2, i.e., A2 occurs after P2 (Normally A2 occurs before P2).o Large left ventricular volume ejected into the aorta results in dilatation of the ascending aorta. Aortic ejectionclick.o Large volume of blood passes through normal aortic valve Aortic ejection systolic murmur (but it is masked by continuous murmur).Clinical manifestations of PDAo Patient may be asymptomatico Symptoms develop early and CHF may develop at 6 to 8th weeks of age.o Common symptoms - Dysnea on exertion, palpitation and frequent chest infections.Signso Tachypnea & Tachycardiao Bounding pulse with wide pulse pressure (with elevated systolic and lower diastolic pressure)o Hyperkinetic cardiac impulseo Systolic or continuous thrillo Accentuated S1o Narrow or paradoxical split of S2 (But it may be masked by continuous murmur since maximum intensity of continuous murmur occurs at S2).o Continous (machinery) murmur - Murmur starts after SI and reaches the peak at S2. It then diminishes and is audible only during a part of the diastole. Murmur is best heard at second left intercostal space and is also heard below left clavicle.o S3 may occur at apex followed by a delayed diastolic murmur.Management of PDAo NSAIDs (most commonly indomethacin) are used to induce closure of PDA, as these drugs inhibit synthesis of prostaglandins (Prostaglanding are involved in maintainance of patency of ductus arteriosus).o If indomethacin is not successful and the ductus remains hemodynamically significant, surgical ligation with or without division of ductus should be performed.
Indomethacin is used in medical management
It is congenital cyanotic heart disease
There is a patent connection between the aorta and pulmonary veins
Mid diastolic murmur is heard
C.H.D.