Doppler tissue imaging analysis was used to examine the relationship between right ventricular function and right ventricular outflow tract damage in 54 patients with repaired tetralogy of Fallot. The patients were divided into three groups: 16 in whom the right ventricular outflow tract was directly sutured (group DS), 23 who had transventricular patch repair (group TVP), and 15 who had transannular patch repair (group TAP). The control group consisted of 16 age-matched patients who underwent patch closure of a ventricular septal defect (group C). The Tei index was obtained from tricuspid and pulmonary Doppler flow velocities. The right ventricular Tei index was significantly greater in groups TVP and TAP than in group DS. Doppler tissue imaging analysis in groups TVP and TAP showed shorter myocardial systolic velocity, diastolic peak velocity, and atrial diastolic peak velocity, lower peak myocardial velocity and acceleration during isovolumic contraction, and prolonged isovolumic relaxation and contraction times compared to groups DS and C. Right ventricular dysfunction is due to the right ventricular outflow tract patch. Thus, the right ventricular outflow tract may be essential for right ventricular ejection and maintenance of right ventricular function.
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