Coronary physiology to guide treatment of coronary artery disease in a patient with severe aortic valve stenosis: friend or foe? A case report.

Background: Severe aortic valve stenosis (AS) is the most frequent valve pathology in the developed world requiring intervention. Due to common factors in pathogenesis, patients with AS frequently have concomitant coronary artery disease (CAD). Determining the relative contribution of each component to the disease state is not easy as there is much overlap in complaints. Moreover, severe AS interferes with the haemodynamic assessment of intermediate coronary lesions. Case summary: In this case report we describe the presentation and management of an 84-year-old patient, with a severely degenerated aortic valve bioprosthesis and an intermediate coronary artery lesion, presenting with acute decompensated heart failure and chest pain. Initial invasive haemodynamic assessment of the coronary lesion provided challenging findings and a second catheterization and intervention was needed to free the patient from his chest pain. Discussion: Optimal assessment and treatment of CAD before valve replacement are controversial. Aortic valve stenosis on itself can lead to subendocardial ischaemia with subsequent angina pectoris. Simultaneously, AS can significantly affect coronary haemodynamics, hereby interfering with intra-coronary haemodynamic assessment of co-existing coronary lesions. Currently used coronary physiological indices are not validated in the AS population and valve replacement has variable effects on the fractional flow reserve and commonly used resting indices, such as the resting full-cycle ratio. Further research on this topic is needed and an overview of currently running studies that will advance this field significantly is provided.