Radiation exposure after myocardial perfusion imaging with Cadmium-Zinc-Telluride camera versus conventional camera.

BACKGROUND: Patient exposure to radiation during the management of coronary heart disease (CHD) can be reduced with more efficient technologies in nuclear medicine, such as the Cadmium-Zinc-Telluride (CZT) gamma-camera for myocardial perfusion imaging (MPI) studies. However, it has been suggested that CZT has lower specificity, which might lead to more downstream radiological procedures, particularly among obese individuals. METHODS AND RESULTS: We evaluated 244 patients with suspected CHD who underwent CZT-SPECT and matched 1:1 according to sex, age, and body mass index (BMI) with those undergoing MPI study with the Anger gamma-camera (Anger-SPECT). The outcome was the total radiation exposure from the MPI study added to the radiation exposure from all subsequent cardiac examinations during a 90-day follow-up. The total radiation dose after 90 days was significantly lower in the CZT-SPECT group (6.4 ± 4.8 vs 9.5±4.9 mSv, P < .001). After adjusting for potential confounders, CZT-SPECT remained associated with lower total radiation dose, but it significantly attenuated among obese individuals (Beta coefficient - 3.73 ± 0.86 for BMI < 30 vs - 2.30 ± 0.92 for BMI ≥ 30 Kg/m2, P for interaction < 0.032). CONCLUSIONS: CZT-SPECT was associated with lower total radiation doses compared to Anger-SPECT, albeit this benefit may be attenuated in obese individuals.

Avaliação de aterosclerose coronária por imagem cardíaca: valor complementar do escore de cálcio à perfusão miocárdica / Coronary atherosclerosis evaluation through cardiac imaging: complementary role of calcium score to myocardial perfusion

Nas últimas décadas, observaram-se avanços na investigação e manejo da doença cardiovascular e uma redução significativa como causa da mortalidade. Entretanto, a doença cardiovascular permanece como a principal causa de morte, em vários países, inclusive no Brasil. Identificar o indivíduo de maior risco para eventos cardiovasculares é de grande importância para que seja possível intensificar e enfatizar medidas de prevenção. As ferramentas diagnósticas não invasivas evoluíram e conseguiu-se, hoje, com boa margem de segurança, identificar os pacientes que mais se beneficiarão dos procedimentos de revascularização do miocárdio, em relação ao tratamento medicamentoso, principalmente, pelo uso da cintilografia do miocárdio. Dúvidas ainda persistem no sentido de como manejar um paciente com fatores de risco para doença cardiovascular, com teste de esforço positivo e cintilografia do miocárdio negativa. O que demonstra a literatura com relação ao valor do escore de cálcio, em pacientes assintomáticos nessas situações? Neste artigo, será feita uma reflexão sobre esses pacientes, os quais são bastante frequentes na prática cardiológica do dia a dia.

Fibroelastoma de valva mitral como causa de acidente vascular isquêmico transitório / Fibroelastoma of the mitral valve as a cause of transient ischemic stroke

A 44-year-old woman had a transient ischemic stroke, fibroelastoma of the mitral valve being the source of the embolus. The patient evolved with neutropenia induced by ticlopidine after 10 days of treatment. We report the major clinical features, therapeutical options, and medicamentous toxicity resulting from the use of antiplatelet drugs