Assessment of Ventricular Function in Tetralogy of Fallot Patients Using Tissue Doppler

摘要

Background: Echocardiographic findings of Tetralogy of Fallot (TOF) are diagnostic in infants and young children, and echocardiography may be the only examination required prior to surgery. Global left ventricular function determined by conventional Doppler may be normal in these patients; but regional myocardial function assessment by tissue Doppler if abnormal in these patients may affect outcome later on. Aim of the Work: to evaluate ventricular functions in Fallot's tetralogy using conventional and tissue Doppler echocardiography (DTI). Patients and Methods: Thirty patients with TOF were included. They included 19 (63.3 %) males and 11 (36.7 %) females, age 37.8 ± 19.31 months. Twenty age-matched healthy subjects (36.3 ± 14.88 months) were included as a control group. Conventional and Doppler tissue Imaging (DTI) were used in the evaluation of both groups. Results: Analysis of the obtained results showed significantly lower ME, ME/A, TE, TE/A and TS but higher TA in TOF group than in healthy controls by DTI. In addition, there was direct correlation between age and ME/A in TOF patients. Comparison of conventional Doppler parameters in the studied groups shows significantly lower ME, ME/A and TE/A but higher TA in TOF patients than controls. Correlation among Doppler Tissue Imaging and conventional Doppler parameters in the TOF cases showed direct correlation between DTI TA and both Doppler TE and TA. In addition, there was inverse correlation between DTI TE/A and Doppler TE and TA. Conclusions: DTI is a reliable utility in the diagnosis of ventricular function in TOF cases with many advantages over conventional echocardiography. Abbreviations TOF: Tetralogy of FallotDTI: Doppler tissue imagingRV: right ventricleME: early diastolic velocity at mitral valve MA: late diastolic velocity ME/A: ratioMS: peak systolic velocity TE: early diastolic velocity at tricuspid valve TA: late diastolic velocity TE/A: ratioTS: peak systolic velocity Introduction Echocardiographic findings of tetralogy of Fallot (TOF) are diagnostic in infants and young children, and echocardiography may be the only examination required prior to surgery. Conventional radiography, MRI, and angiography also are helpful for complete preoperative evaluation in some cases. Angiography has been used for preoperative evaluation of the coronary arteries and peripheral pulmonary circulation. However, intracardiac catheterization may stimulate pulmonary outflow tract spasm. Noninvasive peripheral pulmonary arterial evaluation is possible with MRI [1]. Echocardiography proved to be effective in evaluation of left ventricular volumes in patients with Fallot's tetralogy [2].Right ventricular morphology in tetralogy of Fallot had a great impact in the surgical decision and outcome after total repair. Small ventricular size or impaired function will have a poor prognosis than normal ventricle size and function [3].Left ventricular morphology in tetralogy of Fallot may have a great brunt in surgical decision and outcome after total repair. Small left ventricular size or impaired function may have a poor prognosis than normal left ventricle size and function [4]. Global left ventricular function determined by conventional Doppler may be normal in these patients; but regional myocardial function assessment by tissue Doppler if abnormal in these patients may affect outcome later on [5]. The aim of this study is to evaluate ventricular functions in Fallot's tetralogy using conventional and tissue Doppler echocardiography. Patients and MethodsThe present study was conducted in the period from April, 2005 through April, 2006 at Cardiology Unit, Mansoura University Children's Hospital, Mansoura, Egypt.Thirty patients with TOF were enrolled in the study. They included 19 (63.3 %) males and 11 (36.7 %) females, age 37.8 ± 19.31 months. Twenty age-matched healthy subjects (36.3 ± 14.88 months( were included as a control group with approval of the study by the Institutional Ethics Com