Does RSV infection cause pulmonary hypertension in children undergoing cardiac surgery?

Aims

We wished to determine the incidence of pulmonary hypertension and complications due to Respiratory syncitial virus (RSV) infection in children undergoing cardiopulmonary bypass in a multi-centre randomised trial.

Patients and methods

Children with haemodynamically significant congenital heart disease (CHD) were matched and randomised to receive palivizumab or placebo during the period 2003–2005 in a multi-centre randomised clinical trial of 1287 children. All those who also underwent cardiac surgery were included in the present study, comparing outcomes for those who acquired RSV infection with those who did not (controls), matched for demographics (age and weight at operation), and physiology of cardiac morphology; left to right shunt (L-R), right to left shunt (R-L) and single ventricle physiology (SV). Cardiac surgery was delayed for more than 6 weeks after the RSV infection.

Results

183 children were included in this study of whom 20 suffered from RSV infection during the study period. There were six undergoing correction of L-R, 4 with tetralogy of Fallot or complex transposition (R-L), seven undergoing Glenn shunt (SV), and three others, all at 1 month to 10 months in age. There was no difference in intensive care stay between RSV infected children and controls, or in days of mechanical ventilation, or hospital stay, but supplemental oxygen requirement was increased in L-R by 17% compared to only 3% in controls (p<0.05). In SV 13% had increased oxygen requirement compared to controls (2%) (p<0.05). There was no difference in the R-L group. Duration of heart failure medication tended to be longer in all three groups (L-R more than 6 months in 67% p<0.01, R-L 50% and SV group 63%, both p=NS). Noticeably only 17% of R-L required medication for less than 1 month, versus 48% of controls.

Conclusion

We have shown that RSV infection more than 6 weeks before cardiopulmonary bypass causes significant morbidity, although we found no indirect evidence of pulmonary hypertension after RSV infection. All three RSV groups demonstrated longer duration of medication, possibly representing respiratory dysfunction several months after RSV infection. A prospective study is needed to determine the longer term effects of RSV in CHD.