Ventricular Septal Defect with Heart Failure
An 8-week-old infant has 1 week of cough and sweating during feeds, and his weight has fallen from the 50th to the 10th percentile. Respiratory rate is 72 breaths/min with recession and bibasal crackles. There is a grade 4/6 pansystolic murmur at the left lower sternal border and hepatomegaly. Chest radiography shows cardiomegaly with increased pulmonary vascular markings. What is the most appropriate initial pharmacologic treatment?
- A.Nebulized salbutamol
- B.Intravenous ceftriaxone
- C.Oral furosemideCorrect
- D.Immediate surgical defect closure
Explanation
This infant has congestive heart failure from a large ventricular septal defect, and with an adequate blood pressure the first pharmacologic step is a loop diuretic such as furosemide to relieve pulmonary and systemic congestion. As pulmonary vascular resistance falls over the first 6 to 8 weeks of life, left to right shunting through the defect increases, producing pulmonary overcirculation with tachypnea, wheeze and crackles, sweating with feeds, poor weight gain, hepatomegaly, and cardiomegaly with plethora on radiography. Furosemide reduces preload and pulmonary edema and gives rapid symptomatic relief, after which afterload reduction with an angiotensin converting enzyme inhibitor is added; digoxin is now used only rarely. High caloric density feeding is an essential adjunct because these infants have high energy expenditure and poor intake. If blood pressure were low, diuretics would be hazardous and the priority would be cautious fluid and an inotrope such as milrinone or dobutamine. Salbutamol treats bronchospasm from airway disease and will not relieve cardiogenic pulmonary congestion, and the wheeze here is cardiac in origin. Antibiotics are reserved for proven infection, which is not supported by a normal temperature and a clear cardiac explanation. Surgical closure is definitive but is planned electively once the infant is medically stabilized, typically when heart failure or failure to thrive persists despite optimal medical therapy.
Why each option
- A.
- Salbutamol relieves bronchospasm but does nothing for cardiogenic pulmonary congestion, which is the cause of the wheeze here.
- B.
- Antibiotics are unnecessary without evidence of infection; the picture is fully explained by a large left to right shunt.
- C.
- Correct. Furosemide is the first-line agent for pulmonary and systemic congestion when blood pressure is adequate.
- D.
- Surgery is definitive but follows medical stabilization; it is not the initial pharmacologic treatment.
Reference: Nelson Textbook of Pediatrics, 22nd ed., 2024, Ventricular Septal Defect and Heart Failure in Infants
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