[Quantification of mitral regurgitation by cine-MRI. Comparison with transesophageal echocardiography in 45 patients]

Cine-MRI demonstrates the presence of mitral regurgitation by a signal void. This study was undertaken to assess the value of this method for quantification of mitral regurgitation in a population not excluding either patients with mitral valve prostheses or those with atrial fibrillation. The subjects included had a mean age of 59 years and were referred for transoesophageal echocardiography, either for assessment of valvular heart disease (38 patients), or for detection of atrial thrombosis before external electrical cardioversion (7 patients). Eight patients had mitral valve prostheses and 19 were in atrial fibrillation. Cine-MRI was performed within 12 days of the transoesophageal echocardiography study with a 1.5 tesla magnet, using a sequence of gradient echo in 3 parallel planes in the 4 chamber view. The regurgitation was quantified by MRI from the extension of the signal void in the left atrium. The transoesophageal Doppler echocardiographic criteria were the width of the regurgitant jet at its origin, the intensity of the regurgitation signal recorded by continuous wave Doppler and the extension of the jet within the left atrium. The quantification by degrees 1 to 4 did not differ by more than 1 degree between the 2 techniques in 43 of the 45 patients. Out of 4 left atrial thrombus detected by transoesophageal echocardiography, only 1 was visible by MRI. The authors concluded that quantification of mitral regurgitation by cine-MRI provides similar results to those obtained by transoesophageal echocardiography and that the correlation remains valid in cases of atrial fibrillation. However, Doppler echocardiography provides further valuable information for the clinician.