The emperor's new clothes: hypersensitivity of the new cardiac isoenzymes

Abstract

Right ventricular (RV) myocardial infarction (MI) and pulmonary embolism (PE) are commonly recognized as two of the most challenging and vexing entities in clinical practice. When either is considered in a differential diagnosis, they warrant close consideration because of the life-threatening nature of these conditions. Their signs and symptoms overlap and, on rare occasions, they both can be simultaneously present in a single patient. Cardiac troponins are considered reliable markers of myocardial injury and are critical to the diagnosis of acute coronary syndromes. However, they can also be elevated in cases of PE. We herewith present a case of a woman who initially presented with syncope and then subsequently dyspnea. She manifested elevated cardiac isoenzymes, right-sided electrocardiogram abnormalities, and RV hypokinesis on echocardiography. She was initially diagnosed with RV infarct and managed with an interventional cardiology approach. However, her symptom of dyspnea persisted and the patient was eventually diagnosed with PE. Clinicians should entertain the diagnosis of PE in patients with elevated troponin I and evidence of right-sided cardiac compromise.

Keywords

• right ventricular myocardial infarction
• pulmonary embolism
• cardiac troponins
• conventional troponin assays
• highly sensitive troponin assays