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Pulmonary valve replacement after surgical repair of tetralogy of Fallot.

OBJECTIVE
To evaluate the results of pulmonary valve replacement in patients with severe pulmonary regurgitation after tetralogy of Fallot repair in Hong Kong.


DESIGN
Retrospective review.


SETTING
University teaching hospital, Hong Kong.


PATIENTS
Consecutive patients undergoing pulmonary valve replacement after repair of tetralogy of Fallot between August 2002 and December 2008.


MAIN OUTCOME MEASURES
Magnetic resonance imaging of right ventricular volume and cardiopulmonary exercise test data before and after the operation were documented and compared.


RESULTS
Over a 6-year period, 16 patients underwent pulmonary valve replacement for severe pulmonary regurgitation after prior complete repair for tetralogy of Fallot. There was no in-hospital mortality. The mean time interval between the initial repair and pulmonary valve replacement was 19 (standard deviation, 9) years. In three patients, the indication for pulmonary valve replacement was symptomatic severe pulmonary regurgitation, and asymptomatic progressive right ventricular dilatation in the remaining 13 patients. After pulmonary valve replacement, there was a significant decrease in the mean indexed right ventricular end-diastolic volume from 173 (standard deviation, 44) mL/m(2) to 103 (19) mL/m(2) (P=0.043). After the operation, there was also a tendency for improvement of the right ventricular ejection fraction and the maximum oxygen consumption: from 42% (standard deviation, 9%) to 47% (6%) [P=0.173], and 27 (4) mL/kg/min to 29 (4) mL/kg/min (P=0.208), respectively.


CONCLUSION
Pulmonary valve replacement for severe pulmonary regurgitation after tetralogy of Fallot repair is a safe procedure. However, the indications for such an operation in asymptomatic patients remain controversial. Further studies are required to better delineate the timing of pulmonary valve replacement in this patient group.