Objectives: To test the hypothesis that longitudinal strain of the right ventricle (RV) is significantly reduced in patients undergoing cardiac surgery with extracorporeal circulation and cardioplegic cardiac arrest at the end of surgery, whereas RV ejection fraction remains unchanged. Design: Prospective observational cohort study. Setting: Single university hospital. Participants: Thirty patients with normal myocardial function undergoing coronary artery bypass grafting with cardioplegic cardiac arrest. Interventions: Right ventricular 3-dimensional echocardiography and strain analysis were performed preoperatively, intraoperatively, and postoperatively. Measurements and Main Results: Peak longitudinal systolic strain of the RV lateral and inferior wall, RV outflow tract, and interventricular septum was reduced significantly at the end of surgery after sternal closure compared to preoperatively (lateral: À16 § 5 v À22 § 4, p < 0.001; inferior: À12 § 4 v À19 § 5, p < 0.001; outflow tract, À11 § 5 v. À20 § 6, p < 0.001; septum: À9 § 3 v À14 § 4, p < 0.001), whereas peak circumferential systolic strain of the RV lateral wall had increased significantly (À16 § 4 v-12 § 5, p = 0.008). Right ventricular ejection fraction remained stable (51 § 6% v. 50 § 7%, p = 0.34). Conclusion: In patients undergoing coronary artery bypass grafting with cardioplegic cardiac arrest, the longitudinal contraction of the RV lateral and inferior wall, the RV outflow tract, and the interventricular septum is impaired at the end of surgery. This impairment is compensated by an increase in circumferential contraction without changes in RV ejection fraction.