RESUMEN
Purpose To validate the importance of 67Ga imaging to diagnose activity in rheumatic fever carditis and in the follow-up of treated patients with the disease. Patients and Methods Thirty patients with rheumatic fever were studied. Fifteen males and 15 females aged 7 to 39 years old (median 16 years), were submitted to 67Ga imaging. The patients were divided into two groups. GA 20 pacients who received only clinical treatment and GB11 patients (one from group A) submitted to surgical biopsy. In 12 patients from GA, sequential 67Ga imaging were also realized for the therapeutic follow-up. Fifty-five 67Ga images were reviewed subjectively by experienced observers and a semi-quantitative analysis processed in a dedicated computer was performed with ROI's of 10 x 20 pixels over the projection of the heart and right lung in 22 negative and 33 positive studies. Results Group AIn 19 patients (95%) the 67Ga uptake matched with the clinical evidence, EGC and echocardiogram results. In one patient (5,0%) the 67Ga study was negative, but there were clinical and EKG evidence of activity of the disease; from these data this case was then considered as false negative. Group B In 11 patients submitted to surgical biopsy, the clinical-scintigraphic-histologic correlation matched in 10 cases and mismatched in one. The semi-quantitative analysis of the 67Ga uptake with ROI's over the topography of the heart and right lung showed an percentage index heart x right lung of 114,5 ±17,5% (2s.d.) in normals and 158 ± 30% (2 s.d.) in patients with active carditis: these data had value in the therapeutic follow-up of 12 patients from GA, where occurred good correlation, in every case, of the 67Ga uptake index and clinical evolution and EKG find ings ConclusionThe 67Ga imaging is a non invasive diagnostic method with a good sensitivity to the diagnosis of activity in rheumatic carditis, to evaluate the therapeutic results and to define inactivity for surgical cases