RESUMO
BACKGROUND AND AIM OF THE STUDY: Transthoracic two-dimensional echocardiography (TTE) is currently the 'gold standard' for the evaluation of rheumatic mitral valve disease. Multidetector computed tomography (MDCT) is a promising technique for the evaluation of heart valves. The study aim was to evaluate the planimetry of the mitral valve area (MVA) with 16-row MDCT in comparison with TTE, in patients with rheumatic mitral stenosis. METHODS: Twenty-six patients (18 females, eight males; mean age 41.7 +/- 8.7 years) with rheumatic mitral valve disease, who had been referred for 16-row MDCT for various indications, such as evaluation of the coronary arteries, assessment of pulmonary vein anatomy before catheter ablation of paroxysmal atrial fibrillation, suspicion of aortic dissection or pulmonary embolism, were recruited. All patients were in sinus rhythm. The MDCT acquisition was performed using a 16-row scanner. Echocardiographic planimetry of MVA was performed in the standard parasternal short-axis view within one week. RESULTS: Planimetry of the MVA with MDCT did not differ from that with TTE (1.88 +/- 0.46 cm2 versus 1.83 +/- 0.50 cm2, p = 0.242), and there was an excellent correlation between two techniques (r = 0.923, p < 0.0001). Seven patients had calcific mitral valves (mean calcium score 216.8 +/- 783.8 Agatston units). In these patients, MVA measured by MDCT was 1.73 +/- 0.39 cm2 and by TTE planimetry was 1.72 +/- 0.54 cm2 (p = 0.866; r = 0.963, p = 0.0005). When using the pressure half-time (PHT) method, the MVA was obtained in 24 of the 26 patients. MVA by PHT did not differ from the MVA calculated by TTE planimetry, nor from that obtained with MDCT planimetry (1.79 +/- 0.46 cm2 versus 1.81 +/- 0.51 cm2, p = 0.427 and 1.79 +/- 0.46 cm2 versus 1.86 +/- 0.48 cm2, p = 0.101, respectively). The correlation coefficient for the MDCT-derived MVA and PHT-derived MVA was 0.8969 (p < 0.0001). Although not statistically significant, in nine patients with moderate to severe mitral stenosis (MVA < 1.5 cm2), the MDCT tended to overestimate MVA compared to echo planimetry (1.35 +/- 0.19 cm2 versus 1.28 +/- 0.21 cm2, p = 0.059). CONCLUSION: MDCT enabled accurate planimetry of the MVA in patients with rheumatic mitral stenosis, in comparison with TTE.
