RESUMO
BACKGROUND: We conducted an exploratory analysis to test whether the addition of a CAC scan can increase the applicability of stress-only SPECT-MPI. METHODS: We studied 162 patients referred for rest/stress SPECT-MPI who underwent a CAC scan. Each scan was interpreted by two readers in stepwise fashion: stress-only images; addition of clinical data; and addition of CAC data. At each step, the reader was asked if rest SPECT-MPI was necessary. RESULTS: Stress-only images were interpreted as normal in 62, probably normal in 42, equivocal in 15, probably abnormal in 5, and definitely abnormal in 38 patients. Rest SPECT-MPI imaging was considered necessary, in 0% of normal studies, but in 88% of probably normal studies, and 100% of those with equivocal/abnormal studies. Addition of the clinical data did not materially change this decision. Additional consideration of the CAC scan results did not influence the deemed lack of need for a rest SPECT-MPI with normal SPECT-MPI or the necessity of rest SPECT-MPI with abnormal SPECT-MPI. However, the CAC scan reduced the deemed need for a rest SPECT-MPI in 72% with a probably normal, 47% with an equivocal, and 40% of those with a probably abnormal SPECT-MPI. CONCLUSIONS: Our exploratory analysis indicates that addition of a CAC scan to stress SPECT-MPI tends to diminish experienced readers' deemed need to perform rest SPECT-MPI studies among patients with probably normal or borderline stress-only SPECT-MPI studies. Thus, further study appears warranted to assess the utility of using CAC scanning as a means for increasing the percent of SPECT-MPI studies that can be performed as stress-only studies.
Assuntos
Vasos Coronários/patologia , Imagem de Perfusão do Miocárdio , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Índice de Massa Corporal , Cálcio/metabolismo , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/metabolismo , Eletrocardiografia , Teste de Esforço , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Descanso , Fatores de Risco , Tecnécio Tc 99m Sestamibi , Adulto JovemRESUMO
BACKGROUND: The decision to undergo mitral valve surgery is often made on the basis of echocardiographic criteria and clinical assessment. Recent changes in treatment guidelines recommending surgery in asymptomatic patients make the accurate assessment of mitral regurgitation (MR) severity even more important. OBJECTIVES: The purpose of this study was to compare echocardiography and magnetic resonance imaging (MRI) in the assessment of MR severity using the degree of left ventricular (LV) remodeling after surgery as the reference standard. METHODS: In this prospective multicenter trial, MR severity was assessed in 103 patients using both echocardiography and MRI. Thirty-eight patients subsequently had isolated mitral valve surgery, and 26 of these had an additional MRI performed 5 to 7 months after surgery. The pre-surgical estimate of regurgitant severity was correlated with the postoperative decrease in LV end-diastolic volume. RESULTS: Agreement between MRI and echocardiographic estimates of MR severity was modest in the overall cohort (r = 0.6; p < 0.0001), and there was a poorer correlation in the subset of patients sent for surgery (r = 0.4; p = 0.01). There was a strong correlation between post-surgical LV remodeling and MR severity as assessed by MRI (r = 0.85; p < 0.0001), and no correlation between post-surgical LV remodeling and MR severity as assessed by echocardiography (r = 0.32; p = 0.1). CONCLUSIONS: The data suggest that MRI is more accurate than echocardiography in assessing the severity of MR. MRI should be considered in those patients when MR severity as assessed by echocardiography is influencing important clinical decisions, such as the decision to undergo MR surgery.