Large Abdominal Photopenic Area on 99mTc-Sestamibi Myocardial Perfusion Imaging

Abstract

99m Tc-sestamibi myocardial perfusion imaging is frequently performed in conjunction with exercise or pharmacologic stress testing for evaluation of coronary heart disease. Interpretation of these studies includes systematic review of unprocessed rotating projectional images for evaluation of cardiac size as well as the presence of motion or attenuation artifacts. Occasionally, incidental noncardiac findings are detected on review of the projectional images. We report a case of a patient with a history of autosomal dominant polycystic kidney disease who was found to have a large abdominal photopenic area on the projectional images. The photopenic area corresponded to the location of large intraabdominal cysts on abdominal CT and was consistent with hepatic cysts associated with the patient's known polycystic kidney disease. We review the differential diagnosis of large abdominal photopenic regions identified on myocardial projectional images and the importance of routinely analyzing these images for incidental noncardiac findings. Inci dental noncardiac findings occasionally are detected on review of projectional 99m Tc-sestamibi myocardial perfusion images (1). Here, we report a case in which a large abdominal photopenic area was found on myocardial perfusion imaging in a patient with a history of autosomal dominant polycystic kidney disease. CASE REPORTA 69-y-old man was seen in our cardiology specialty office for evaluation of symptoms of shortness of breath with exertion and abnormalities found on a standard exercise test. He had experienced occasional symptoms of dyspnea with exertion during the past 3 mo. He denied symptoms of exertional or rest chest pain. His cardiac risk factors included a history of borderline hypertension and a family history of cardiac disease. The past medical history was significant for known autosomal dominant polycystic kidney disease. He had been found to have large renal and hepatic cysts on an earlier CT scan and was undergoing nephrology evaluation for moderate renal insufficiency.On physical examination the blood pressure was 121/82 mm Hg, the heart rate 72 beats per minute, and the respiratory rate 16 breaths per minute. The lungs were clear to auscultation. On cardiac examination, there was a regular rhythm with a soft systolic murmur at the left sternal border. On abdominal examination, there was mild diffuse distention without tenderness to palpation.The electrocardiogram showed sinus rhythm and nonspecific ST-T changes. A recent standard exercise treadmill stress test had demonstrated abnormal electrocardiographic changes at peak exercise in the inferior and lateral precordial leads.In light of the patient's symptoms and electrocardiographic abnormalities observed on standard stress testing, repeated treadmill stress testing was performed in conjunction with same-day stress-rest 99m Tc-sestamibi myocardial perfusion imaging. The patient reached an exertional level of 10 metabolic equivalents and 100% of maximum predicted heart rate without symptoms of chest pain. Abnorm...

Assessment of Cardiovascular Disease in Autosomal Dominant Polycystic Kidney Disease

“…Occasionally, incidental non-cardiac findings are detected upon review of the projectional images. In particular, a case of a patient with a history of ADPKD who was found to have a large abdominal photopenic area on the projectional images consistent with hepatic cysts was described [62].…”

Incidental Findings on Myocardial Perfusion SPECT Images

“…The literature has described other causes of abdominal photopenia on the rotating raw SPECT images, such as simple hepatic cysts (Fig. 17), echinococcal cysts, cholecystitis (18), and tumors ( Fig. 18).…”