2678

INCREASE IN DIAMETER OF VENTRICULAR SEPTAL DEFECT DURING INFANTILE PERIOD

Ito T, Okubo T

Nakadori General Hospital, Akita, Japan

Objective: Serial changes in diameters of venticular septal defect (VSD) were studied to elucidate the relationships between the enlargement of VSD and the clinical features in infants.

Methods: We studied 65 infants with VSD those were classified into 3 groups from clinical feature The infants with severe respiratory symptoms and significant failure to thrive were classified as group A (n=15), those underwent intra-cardiac repair by 6 months of age The infants with no respiratory symptoms and mild or moderate failure to thrive were classified as group B(n=38),those were operated between 6 months and 2 years Group Chad no trivial clinical symptoms and did not require operation(n=12).Changes in the diameters of VSD were periodically measured by two-dimensional echocardiography using the standard four chamber view or short axis view in which plane the VSD appears the largest in each case Serial changes in the VSD diameter and the ratio of the VSD diameter to body surface area were compared among the 3 groups A paired Student's t-test was used to compare data Statistical significance was accepted at P<0.05.

Results: From operative findings most of patients in group A (93%) and group B (82%)had perimembranous defects The remainders had outlet defects Group A showed the rapid enlargement of VSD and the mean diameter at the age of 5 months was 75%larger than that at the age of 1 month (increase from 5.5to 9.6mm,p<0.05).Other two groups(B,C) showed a slower enlargement compared with group A Group A Showed significant increase in the diameter per body surface area although other two groups showed no significant changes in those during the study period.

Conclusion: Failure to thrive in VSD infants correlates with rapid increase in VSD diameter to the body surface area after the age of 1 month Careful observation of the changes in VSD diameter to body surface area by echocardiography is very important to predict the clinical course and to decide the operation indication.