Assessment of systemic right ventricular function in patients with transposition of the great arteries using the myocardial performance index: comparison with cardiac magnetic resonance imaging.
BACKGROUND
Assessment of systemic right ventricular (RV) function is a key point in the follow-up of patients with transposition of the great arteries (TGA). Current echocardiographic assessment of RV function is at best an estimate, and cardiac magnetic resonance (CMR) is considered the gold standard. However, this technique is expensive, has limited availability, and requires significant expertise to acquire and interpret the images. The myocardial performance index (MPI) has recently been studied for assessment of pulmonary RV function and shows promise as a simple yet powerful tool for assessing patients with RV dysfunction of various origins. We set out to compare MPI and CMR assessment of systemic RV function in patients with TGA.


RESULTS
Data from patients with TGA (11 with congenitally corrected TGA, 18 with surgically corrected TGA) who had CMR within 6 months of their echocardiogram were reviewed. The average systemic RV ejection fraction (RVEF) by CMR was 39.4+/-11.4%, and the systemic RVMPI for this group was 0.56+/-0.21. There was a strong negative correlation between the systemic RVMPI and systemic RVEF by CMR (r=-0.82, P<0.01). The systemic RVEF can be estimated from this formula: RVEF=65%-(45.2xMPI).


CONCLUSIONS
MPI can be used in patients with systemic RVs to assess global function and to estimate an EF with good accuracy.
Salehian
Omid
O
Toronto Congenital Cardiac Center for Adults and Echocardiographic Laboratory, Division of Cardiology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada.
Schwerzmann
Markus
M
Merchant
Naeem
N
Webb
Gary D
GD
Siu
Samuel C
SC
Therrien
Judith
J
D000328:Adult; D005260:Female; D006334:Heart Function Tests; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D015588:Observer Variation; D015203:Reproducibility of Results; D012494:Sampling Studies; D013318:Stroke Volume; D014188:Transposition of Great Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014463:Ultrasonography