[Magnetic resonance angiography. Value for evaluating the patency of aortocoronary bypass]. / Angiographie par résonance magnétique. Intérêt pour évaluer la perméabilité des ponts aorto-coronaires.

OBJECTIVE: Assessment of coronary bypass patency with conventional angiography can be limited by difficulties in selective catheterism. The aim of this work was to determine whether ultrarapid sequences proposed for imaging coronary arteries could be used to evaluate bypass patency. METHODS: Twenty patients (mean age 66 +/- 7 years) with 42 aorto-coronary bypasses (32 venous and 10 mammary bypasses) underwent conventional angiography and magnetic resonance angiography within a 1 week interval. All patients were evaluated 1 to 15 years after bypass surgery. Magnetic resonance imaging (MRI) was performed in ventral supine position using a flexible surface coil. Breathhold electrocardiogram-synchronized sequences were acquired using a 1.5 T magnet, with TR = 156 ms, TE = 8 ms, slice thickness 5 mm, 126.256 matrix, and a 7 to 11 segmentation per cardiac cycle. At most, 24 transverse slices were acquired for each patient. RESULTS: Twenty-six patent bypasses were correctly identified with MRI. Three bypass were patent on angiography and appeared occluded on MRI (2 mammary and 1 venous bypass). Nine bypasses were classed as occluded with both techniques. MRI demonstrated patency in one bypass for which selective catheterism was not possible. The sensitivity of MRI for the diagnosis of patency in aorto-coronary bypasses was 89% with a 92% specificity. MRI did not identify 1 out of 4 bypass stenoses. CONCLUSION: We conclude that the ultrarapid breath-hold magnetic resonance sequences can be used to determine patency of aorto-coronary bypasses with good sensitivity and specificity. Our results would suggest however that this method is inadequate for the diagnosis of bypass stenosis.

[Heart valve prosthesis from autologous pericardium. Preliminary results apropos of 15 patients]. / La prothèse cardiaque en péricarde autologue. Résultats préliminaires à propos de 14 patients.

The concept of a heart valve prosthesis made from autologous pericardium is based on the idea of creating and developing a valve with a longer life than heterografts or homografts due to the absence of tissue degeneration causing the deterioration of both of these types of bioprostheses. The first attempts using the fascia lata or the pericardium, implanted in the seventies, were unsuccessful due to problems with pretreatment of the pericardium and other purely technical difficulties. J. Love et al then developed a technique based on Carpentier's earlier work, where a valve is made extemporaneously using the autologous pericardium. We applied this technique in 14 patients from June 1994 to 1995. The mean age of the patients was 68 years (7 males, 7 females). The aortic valve was replaced in all cases. Preoperative findings were: aortic stenosis (n = 7), aortic regurgitation (n = 1), aortic valve disease (n = 6). Two patients also had mitral valve disease and 3 had coronary artery disease. There were no operative deaths and no patients were lost to follow up. Clinical state was satisfactory with a follow-up of 1 to 10 months. Postoperative Doppler echocardiography was performed at 3 and 6 months and showed gradients were very low. This group of patients demonstrated the value and applicability of the concept. The validity of the technique will be evaluated as a function of the long-term results.

[Myxoma of the mitral valve; apropos of 2 surgically treated cases. Review of the literature]. / Myxome de la valve mitrale; á propos de deux cas opérés. Revue de la littérature.

The authors report two cases of anterior mitral valve myxoma. This is an exceedingly rare localisation and these cases add to the other 8 previously reported cases. Intracardiac tumours and valvular endocarditis may be detected non-invasively by echocardiography but the precise diagnosis may be extremely difficult: mitral valve myxoma is an exceptionally rare condition. Treatment was surgical in both reported cases.