In-stent restenosis (ISR) is a critical drawback of coronary stents, although initially described as benign, guidelines both support the use of intravascular imaging in the diagnosis and treatment of stent failure (Class IIa); however, our case highlights the limitation of optical coherence tomography in the assessment of the ISR (stent failure), it also highlights the association of self-limited severe acute respiratory syndrome coronavirus-2 illness and an acute coronary syndrome ISR presentation.

High-sensitivity cardiac troponins expedite the evaluation of patients with chest pain in the emergency department. The utility of troponins extends beyond the acute coronary syndromes to accurate the diagnosis of myocardial injury. Troponins are best friends for physicians; however, they are a double-edged sword if not interpreted appropriately. Misdiagnosis is harmful with regard to patient outcomes. The present review focuses on the recent updates in the understanding and interpretation of high-sensitivity troponins in various acute clinical settings. Common mistakes and gray zones in the interpretation of troponins, the concept of myocardial injury versus infarction, newer entities like myocardial infarction (MI) with Nonobstructive Coronary Arteries, recent controversies over the definition of periprocedural MI, complementary role of imaging in the diagnosis of myocardial injury and the role of troponins in the current COVID-19 pandemic are discussed.