Aortic valve repair(AVr) has become an attractive alternative for the correction of aortic insufficiency(AI) as compared to aortic valve replacement; however, little information exists regarding the effects of acute AI and subsequent AV repair(AVr) on ventricular and valvular dynamics. The objective of this study was to measure and compare hemodynamic and echocardiographic properties in a novel, ex-vivo model of severe acute AI due to cusp pathology followed by valve repair. Porcine aortic roots with intact aortic valves were placed in a left heart simulator mounted with a high-speed camera for baseline hemodynamic assessment. 3-D echocardiography was used to evaluate valve function, AI, and leaflet coaptation (coaptation surface area [CoSA]). In the first model, an 8mm diameter circular perforation was created in the body of the non-coronary cusp (NCC) leaving an intact free margin(AI “lesion” assessment) followed by patch repair (AVr “treatment” assessment). In the second model, 75% of the NCC was excised followed by cusp replacement with a pericardial patch. Hemodynamic and echocardiographic data are expressed as medians with interquartile ranges. Finite element modeling (FEM) was performed in both models to understand stress characteristics. Wilcoxon-signed rank tests were used to determine significance between paired sample experiments. The cusp perforation model demonstrated a significant increase in the regurgitant fraction (RF) after AI was created (control= 5.2 [5,5.6] % versus AI= 50.1 [49,53] %; p=0.04) and returned to baseline “control” levels after AVr (AVr= 11.7 [7.1,11.8] %; p=0.14). The cusp excision and repair model demonstrated a significant increase in RF after AI was created (control= 4.8 [3.2,9.1]% versus AI = 69.6 [69.2,75.3]%; p=0.04) but returned to baseline with valve repair “treatment” (AVr= 10.4[9.7,11] %; p=0.5). Furthermore, CoSA was significantly reduced after creation of AI (1.54cm2 versus 1.14[0.75,1.18] cm2; p=0.04) which then returned to baseline levels after AVr (1.54cm2 versus 1.59cm2; p=0.68). Finally, after comparing all hemodynamic parameters after valve repair in both models, there was no significant difference. Figure 1 summarizes the findings with FEM. We successfully simulated acute AI and effective repair due to clinically relevant cusp pathology in an ex-vivo left heart simulator along with 3-D echocardiography. After valve repair, both models demonstrated similar leaflet stress changes (+24% increase) suggesting that no matter the intervention, the repaired cusp retains major stress; making it more vulnerable to failure. Further investigation using this reproducible ex-vivo protocol with FEM will help reveal optimal therapeutic options in more complex models of AI.