Incidental Finding of Transthyretin Cardiac Amyloidosis During Coronary Artery Bypass Grafting.

Transthyretin cardiac amyloidosis (ATTR-CA) is a condition characterized by extracellular deposition of misfolded transthyretin proteins in the myocardium and has been historically difficult to diagnose due to diverse clinical manifestations and nonspecific, variable electrocardiogram (ECG) and echocardiogram findings. Advancements in noninvasive cardiac imaging have led to significant increases in diagnoses of ATTR-CA. Once thought to be a rare condition, there is growing evidence to suggest that ATTR-CA is more prevalent than previously understood, prompting the need for early diagnosis and intervention. We outline the case of a 78-year-old male who presented to the emergency department with chest discomfort, shortness of breath, dizziness, and diaphoresis. He was found to have severe coronary artery disease (CAD) and intermittent complete heart block. Cardiac dysfunction was unable to be resolved by percutaneous coronary intervention (PCI) and thus the patient was referred for coronary artery bypass grafting (CABG). Intraoperatively, the patient's heart was found to be abnormally thickened and fibrosed. Biopsy of the cardiac tissue and evaluation using technetium-99m pyrophosphate scintigraphy, single-photon emission computed tomography, and liquid chromatography-tandem mass spectrometry revealed ATTR-CA. There is a need for fast and low-cost screening tools to allow for early identification of the disease. Diagnostic clues for cardiac amyloidosis include the presence of carpal tunnel syndrome, lumbar spinal stenosis, atrial fibrillation, treatment-resistant heart failure with preserved ejection fraction, and a thickened left ventricular wall. Given the presence of these red flag symptoms, clinicians should have a heightened index of suspicion for ATTR cardiac amyloidosis in elderly patients even when presenting in acute settings.

Untreated Primary Hypothyroidism Manifesting as Cardiac Tamponade.

Hypothyroidism is a condition characterized by low thyroid hormone levels that can affect multiple organ systems with varying symptomatology. Common cardiac manifestations of hypothyroidism include bradycardia and decreased cardiac output. Pericardial effusion can also occur as a result of the condition and rarely can progress to cardiac tamponade. Patients with cardiac tamponade occurring as a result of underlying hypothyroidism can present atypically compared to those experiencing cardiac tamponade due to other causes. Patients with cardiac tamponade as a result of underlying hypothyroidism may present as minimally symptomatic with stable vital signs. Close monitoring of patients with pericardial effusions with underlying hypothyroidism is essential to permit early diagnosis and treatment of the condition. We outline the case of a 73-year-old male presenting with cardiac tamponade due to underlying hypothyroidism necessitating an urgent pericardial window.