Ultrasound Assessment of Right Ventricular Function in Pediatric Heart Disease.

Abstract

While the right ventricle has been regarded in the past as a passive conduit for delivery of systemic venous blood to the lungs, the pathophysiologic significance of right ventricular (RV) dysfunction is increasingly recognized. The right ventricle functions either as a pulmonary or systemic ventricle in children, depending on the underlying congenital or acquired heart condition. Children with repaired tetralogy of Fallot and concomitant pulmonary regurgitation represent an important cohort in whom the significant problem is chronic RV volume overload. On the other hand, paediatric patients with chronic RV pressure overload include those with a systemic right ventricle in the setting of congenitally corrected transposition of the great arteries or after atrial switch operation, and those with systemic pulmonary hypertension. The importance of serial monitoring of RV function in these at-risk patients cannot be overemphasized. Notwithstanding the increasing role of cardiac magnetic resonance in the assessment of RV function, echocardiography remains to the most commonly used modality in daily clinical practice. The complex geometry of the right ventricle precludes, however, the use of geometric assumptions in functional assessment. M-mode assessment of tricuspid annular plane systolic excursion and tissue Doppler interrogation of systolic and diastolic regional myocardial velocities can be easily performed and applied by the bedside in the routine assessment of RV function. Additionally, the Doppler-derived myocardial performance index, which is independent of ventricular geometry and takes into account of systolic and diastolic function, has also increasing been used to assess global RV performance. Real-time three dimensional echocardiography and myocardial deformation imaging have shown great promise in the assessment of subpulmonary and systemic RV function, and efforts have been made to facilitate their translation into clinical practice. In conclusion, advances in echocardiographic imaging have revolutionized the evaluation of RV performance and shed light on the pathophysiology of RV dysfunction in paediatric congenital and acquired heart disease.