When to intervene in aortic stenosis; can cardiac troponin I in the first morning urine be our guide?

Abstract

Aortic stenosis is one of the most prevalent acquired valvular diseases in the Western world. Despite its high incidence, timely intervention through valve replacement remains a diagnostic challenge. Recent studies suggest that measuring cardiac troponins in the first morning urine may have potential clinical applications. In healthy individuals, concentrations of troponin I in the first morning urine are several times higher than in plasma. Various conditions that damage the heart, such as arterial emergencies or cardiotoxic therapy, lead to an increased concentration of cardiac troponin I in the first morning urine. Conversely, in patients with severe aortic stenosis scheduled for operative treatment, concentrations of cardiac troponin I in the first morning urine are barely detectable. This phenomenon may result from myocardial remodeling and altered clearance of troponin I from the heart. We hypothesize that reduction in the concentration of troponin I in the first morning urine indicates the onset of cardiomyocyte necrosis, adverse myocardial remodeling, and myocardial fibrosis during the progression of aortic stenosis.