Introduction: The different non-invasive examinations do not result in unambigous results about the long-term determination of right ventricular function providing systemic circulation in children with transposition of the great arteries operated with Senning procedure.
Aim: The goal of study was to determine the application of MRI for the observation of right and left ventricular morphology and function, for the recognition of the progression of the disease, and for the necessity of reoperation.
Methods: The authors have observed the morphology and function of the right and left ventricule by ECG triggered short axis MR pictures. For the analysis of MR pictures MASS 5.0 software was used. Authors have determined the end systolic and end diastolic volume, the ejection fraction, the mass, and the stroke volume of the right ventricule, the end systolic and end diastolic volume, ejection fraction, the mass, and the stroke volume of the left ventricle, and the shunt volume. The values of these data corrected to body mass have been calculated.
Patients: 176 Senning operations took place between 1980 and 1996. MRI exploration at 21 of the 118 analyzed patients were carried out.
Results: The right ventricular ejection fraction value at Senning operated patients is significantly different (49 +/- 9% vs. 70 +/- 4%) from those of healthy children (P < 0.01). Right ventricular stroke volume/m2 and right ventricular end systolic volume/m2 were significantly different compared to normal (43 +/- 10 ml/m2 vs. 48 +/- 7 ml/mn and 46 +/- 16 ml/m2 vs. 21 +/- 5 ml/m2, p < 0.05). Authors found also significant differences in left ventricular ejection fraction in Senning patients as compared to normal (60 +/- 9% vs. 70 +/- 6%, p < 0.01).
Conclusion: MRI, which is a reliable method of objective determination of right ventricular function, became an available method in Hungary. According to the results, authors might presume that the development of right ventricular dysfunction is expected even among Senning operated children without clinical symptoms, so more frequent control is required. The pathological left ventricular parameters may be explained by ventricular interactions. Authors find MRI an important part of the complex follow-up protocol of Senning operations. MRI data extended by results of other non-invasive explorations are appropriate for the follow-up of right ventricular dysfunction.