In vitro investigation of coronary artery fluid dynamics in normal and anomalous models under rest and exercise conditions

Coronary perfusion can be compromised by anatomical anomalies or flow instabilities, potentially triggering ischemia or sudden cardiac death (SCD), especially during intense physical activity. Among these anomalies, the anomalous origin of the left coronary artery (LCA) from the right sinus of Valsalva is strongly associated with SCD in young athletes; however, its hemodynamic mechanisms remain poorly understood. This study presents an in vitro investigation of coronary fluid dynamics and wave propagation using two compliant models of the aortic root and proximal coronary arteries—one with normal anatomy and another with an anomalous LCA origin and intramural course. Each model included a bioprosthetic aortic valve and was tested under rest and exercise conditions. Pressure and flow were measured simultaneously at multiple sites, and wave intensity analysis revealed polarity reversal and secondary peak amplification in the anomalous LCA. Despite identical geometry, the right coronary artery (RCA) also exhibited altered wave intensity and flow patterns in the anomalous model. Additionally, wave speed calculations showed that, in the anomalous LCA, wave speed decreased during rest but increased during exercise—a hallmark of dynamic pathology. The RCA showed the opposite trend, despite unchanged anatomy, underscoring systemic effects of localized anomalies. These findings demonstrate that anomalous coronary anatomy can disrupt global wave propagation and induce dynamic pathology, contributing to ischemic risk during exertion. The results support the relevance of wave-based diagnostics in assessing coronary perfusion and provide new insight into the mechanisms underlying exercise-induced ischemia in anomalous coronary conditions.