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very confusing to me.. any one who could tell why the answer E but not B is the correct answer..
a term male infant is foumd to be cyanotic shortly after birth and requires endotracheal intubation.On physical examination,his blood pressure 68/34mmHg (equall in all four extremitis),pulse 180/min,respiratory rate is 32/min.His precordium is hyperdynamic,has gradeIII systolic murmur and a single S2.cxr showed normal sized heart and increased pulmonary vascular markings.An arterial blood gas on Fio2 of 100% shows PH of 7.34,Paco2 of 47mmHg and PaO2 of 46mmHG.hich of the following diagnosis is most consistent with these findinings
A Atrial septal defect
B hypoplastic left heart syndrome
C patent ductus arteriosus
D tetralogy of fallot
E total anamolous pulmonary venous return
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hi quanser ..me too favour your answer ...early cyanosis...HLHS....i don't have much depth in this ....
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may be B is associated with cardiomegaly on CXR, but at the same time TAPVR looks like figure of 8 on CXR.
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B hypoplastic left heart syndrome
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B. hypoplastic left heart.
and remember also the treatment: PG-E1 to keep the ductus arteriosus open since systemic circulation depends on the blood passing through the ductus arteriosus from the pulmonary artery to the aorta.
a similar Q in NBME. similar vignette; child in cyanosis and shock; his situation stabilized after giving him a drug ( it is PG-E1), what is the drug s mech of action ( keeping the ductus art. open).
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WELL THE ANSWER in Kaplan is eee, guys, as I said in the first line.... toally missing the point
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in TAPVR: wide and fixed split S2.
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Total anomalous pulmonary venous return (TAPVR) occurs in about 1%-2% of patients with congential heart disease. There are four types of TAPVR causing left-to-right shunt: Supracardiac, cardiac, infracardiac, and mixed. In the supracardiac type, pulmonary veins join to form a common vein which drains into the SVC. In the cardiac type, the common pulmonary veins drain into the right atrium directly or via the coronary sinus. In the infracardiac type, the common pulmonary vein courses downward through the diaphragm into the portal vein, which then drains via hepatic veins into the inferior vena cava.
Anomalous pulmonary venous return could be total or partial. An atrial septal defect is necessary for survival, since the oxygenated blood (from the pulmonary veins) must somehow reach the left side of the heart. Symptomatology depends on the amount of mixing and whether or not the pulmonary veins are obstructed. Cyanosis and signs and symptoms of congestive heart failure develop and progress rapidly. There may be a grade 2/6 systolic ejection flow murmur heard along the left sternal border, or it may be absent. The electrocardiogram shows right ventricular hypertrophy and right atrial hypertrophy. Chest x-ray shows increased pulmonary vascular markings or even edema, and the heart may be normal in size or minimally enlarged. The echocardiogram may show right ventricular volume overload, and a color-flow Doppler study may help in locating the common pulmonary venous channel and its drainage. If the resolution is poor, cardiac catheterization and angiocardiography may help in delineating the anomaly further. Treatment consists of correction of the defect by surgery. If surgery is delayed and there is inadequate mixing, palliative balloon septostomy may be performed. Prognosis is good after surgery. Prognosis is poor in neonates with obstructive TAPVR. Long term follow up is needed to assess restenosis and late arrhythmias.
Hypoplastic left heart syndrome consists of a combination of mitral stenosis or atresia, severe aortic stenosis or atresia, and a small left ventricle. Systemic circulation depends on the patency of the ductus. These infants may appear reasonably well at birth until either the pulmonary vascular resistance drops or the PDA closes. They then present with shock, variable cyanosis, poor pulses, poor perfusion and CHF. A systolic murmur may or may not be present. Chest x-ray shows increase vascularity and EKG may show RV hypertrophy. Echocardiography is diagnostic. Early management consists of administration of PGE1 and treatment of CHF. Surgery consists the Norwood surgical procedure and a few centers perform cardiac transplantation for this lesion. Prognosis is guarded.
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anyone else w/ more info...DDx
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got a good one down: for B, the cyanosis often happens after 24-48 hours later, (along the closure of PDA), while for E, it happens sooner
Also for B, you might see hepatomegaly which may help to ddx
other than that, B and E CAN present very similar s/s
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