OBJECTIVES:

I. Compare the total daily energy expenditure in infants with ventricular septal defects vs healthy control infants.

PROTOCOL OUTLINE:

Height, weight, and vital signs (including oxygen saturation by pulse oximetry) are measured on Day 1. Resting energy expenditure, oxygen consumption (VO2), carbon dioxide production (VCO2), and resting respiratory exchange quotient (RQ) are measured using open circuit respiratory calorimetry on Day 1. Patients undergo assessment of total daily energy expenditure using the doubly labeled water method comprised of oral deuterium and oral oxygen O 18 with the next scheduled feeding on Day 1. Urine samples are collected prior to isotope administration, then serially for approximately 12 hours after isotope administration on Day 1, and then daily on Days 2-7. These samples are analyzed by mass spectrometry. On Day 1, patients also undergo echocardiogram to confirm size of defect and measure the degree of pulmonary/systemic blood flow ratio and pulmonary artery pressures.

PROTOCOL ENTRY CRITERIA:

--Disease Characteristics--

Infants with moderate to large ventricular septal defect (VSD) by most recent echocardiogram who meet the following conditions: no other concurrent heart or lung disease; no chromosomal defects or congenital anomalies

OR

Healthy control infants without VSD who meet the following conditions: clinically well; no heart disease; no chromosomal defects or congenital anomalies

--Prior/Concurrent Therapy--

Surgery: VSD infants -- No prior cardiac surgery or palliative procedures; VSD and control infants -- Greater than 6 weeks since other prior surgery

Other: VSD and control infants: Greater than 6 weeks since prior hospitalization