SPECT and PET in ischemic heart failure.

Heart failure is a common clinical syndrome associated with significant morbidity and mortality worldwide. Ischemic heart disease is the leading cause of heart failure, at least in the industrialized countries. Proper diagnosis of the syndrome and management of patients with heart failure require anatomical and functional information obtained through various imaging modalities. Nuclear cardiology techniques play a main role in the evaluation of heart failure. Myocardial single photon emission computed tomography (SPECT) with thallium-201 or technetium-99 m labelled tracers offer valuable data regarding ventricular function, myocardial perfusion, viability, and intraventricular synchronism. Moreover, positron emission tomography (PET) permits accurate evaluation of myocardial perfusion, metabolism, and viability, providing high-quality images and the ability of quantitative analysis. As these imaging techniques assess different parameters of cardiac structure and function, variations of sensitivity and specificity have been reported among them. In addition, the role of SPECT and PET guided therapy remains controversial. In this comprehensive review, we address these controversies and report the advances in patient's investigation with SPECT and PET in ischemic heart failure. Furthermore, we present the innovations in technology that are expected to strengthen the role of nuclear cardiology modalities in the investigation of heart failure.

Myocardial bridge: an unusual cause of asymptomatic ST-elevation during treadmill stress test causing functional ischaemia.

Myocardial bridges are congenital structural abnormalities with debated clinical relevance; they may be traditionally asymptomatic or associated with various clinical manifestations, some of which may be potentially fatal. We report on a 60 years old man, who underwent a follow-up stress/rest myocardial perfusion scintigraphy developing asymptomatic exercise-induced ST-elevation and demonstrating completely reversible ischaemia in the scintigraphic images. Subsequent coronary angiography showed no artery stenosis, but revealed an intramyocardial pathway of the left anterior descending artery throughout a myocardial bridge. In conclusion, to our knowledge, this is the first reported case of asymptomatic exercise-induced ST-elevation secondary to a myocardial bridge.

Incidental pathologic extracardiac uptake of 99mTc-tetrofosmin in myocardial perfusion imaging.

Technetium-99m-tetrofosmin ((99m)Tc-TF) myocardial perfusion studies have incidentally detected various extracardiac abnormalities. The interpretation of these findings may be essential for early diagnosis and treatment of important diseases. We present a rare case of a mediastinal thymoma incidently detected during myocardial perfusion imaging. A 60 year-old woman, with precardiac symptoms of possible myocardial ischemia, underwent a (99m)Tc-TF stress-rest single photon emission tomography test. Intense uptake of the radiotracer in the left paracardiac area, was observed. The computerized tomography and the magnetic resonance imaging tests revealed a mass in the left lower anterior mediastinal area. Biopsy and subsequent histology showed that this mass was a thymoma.

Menstrual cycle disorders after therapy with iodine-131.

OBJECTIVE: To investigate any abnormalities of the menstrual cycle and/or pregnancy in women <40 years old who had received radioiodine (I-131) therapy for thyroid cancer. DESIGN: Case-control study. SETTING: General military hospital in Athens, Greece. PATIENT(S): Forty-five women of childbearing age with thyroid cancer that were treated with I-131 from December 1996 to May 2003 were compared to 83 age-matched control females. INTERVENTION(S): The patients' charts were reviewed, and in addition patients were contacted by telephone and asked detailed questions about their previous gynecologic history and any problems after treatment (menstrual cycle and pregnancy). MAIN OUTCOME MEASURE(S): Abnormalities of menstrual cycle and/or pregnancy. RESULT(S): Overall, 14 of 45 women (31.1%) had menstrual cycle irregularities after treatment. Eight patients (17.8%) had normal menstrual cycles before therapy and six (13.3%) had pretreatment menstrual cycle irregularities that persisted or were exaggerated after therapy. In the control group, 12 of 83 women (14.5%) reported menstrual cycle irregularities. The patients' menstrual cycle and menses irregularities were significantly increased after I-131 therapy (P=.02) compared with the control group and seemed to increase with age. After therapy a total of seven children were borne by 6 of the 45 patients (13.3%). No premature births or miscarriages were noted. CONCLUSION(S): The study found a significant increase of patients with menstrual cycle and/or menses irregularities after treatment with I-131. However, therapy with I-131 did not result in any subsequent pregnancy abnormalities such as premature births or miscarriages.