Cases from a busy nuclear cardiology laboratory

Abstract

A 46-year-old man with a history of coronary artery disease (CAD) status post drug-eluting stent placement 8 years prior, and heart failure with reduced left ventricular (LV) ejection fraction (EF) presented to the emergency room with shortness of breath, chest pain, and malaise of 1 month duration. Physical examination was normal with a heart rate of 87 beats per minute (bpm) and blood pressure of 129/83 mmHg. The chest xray showed no acute abnormality. The electrocardiogram (ECG) is shown below (Figure 1A). Laboratory studies were remarkable for an elevated hemoglobin (17.3gm/dl), normal BNP (41.0 pg/ml), and undetectable Troponin-I (\\0.030 ng/ml). He was admitted to the chest pain observation unit where repeat troponin and ECG were unchanged 6 hours later. A regadenoson stress Single Photon Emission Computed Tomography (SPECT) myocardial perfusion imaging (MPI) study with technetium-99m sestamibi was performed. The perfusion images (Figure 1B) showed no perfusion defects, and the LV EF was 39%. There was, however, increased radio-tracer uptake in the right ventricle (RV) with associated RV dilatation. The coronary angiogram showed mild diffuse disease with a patent stent in the mid right coronary artery. The right heart catheterization revealed pulmonary arterial hypertension (Table 1). Teaching Point