Philippine Journal of Surgical Specialties Vol. 69, No. 1, January-June, 2014, pp 18-24

Tetralogy of Fallot Correction in Low Z-scores: Expanding the Use of the Valve-sparing Approach

Author(s): Sabrina Anne G. Gonzales, M.D.; Richard S. Nicolas, M.D. and Gisel T. Catalan, M.D., F.P.C.S.

Sparing the pulmonary valve (PV) complex in tetralogy of Fallot (TOF) repair prevents pulmonary regurgitation and consequently, the need for valve replacement. Traditional criteria for employing a valve-sparing strategy include a PV z-score of > -2. This retrospective cohort study aimed to establish differences in outcomes between patients with low and high z-scores who underwent a pulmonary valve-sparing technique of TOF correction.

From 2002 to 2012, 59 patients were subjected to a PVsparing TOF repair. Of these, 25 patients had low z-scores? -3 (Group 1), while 34 patients had high z-scores > -3 (Group 2). A retrospective review of patient outcomes and follow-up two-dimensional transthoracic echocardiograms in the immediate and intermediate postoperative periods was conducted.

There was no significant difference in baseline patient characteristics except in PV z-scores. Average z-scores were -4.85 for Group 1 and -1.45 for Group 2 (P-value 0.00). No significant difference in immediate postoperative outcomes was noted between groups, specifically in terms of arrhythmias, conversions, early reoperations, morbidity and mortality. There were three deaths (5%) in the series. For intermediate outcomes, Group 1 had a higher degree of residual stenosis than Group 2; however, this did not translate to an increase in late reoperation rates. In both groups, there was note of a significant decrease in residual obstruction through time (P-value 0.00).

A pulmonary valve-sparing TOF repair can be successfully utilized even in patients with low pulmonary valve z-scores, with similarly acceptable outcomes as in those with larger pulmonary valve annuli.

Key words: Tetralogy of Fallot, pulmonary valve, reoperation