Figure 5:  (A and B) Area at 4 defined time points (ED, MS, ES, MD) throughout the cardiac cycle for single and double rings at the annulus and STJ. (C and D) Cross-sectional diameters NC–LR, RC–LN and LC–RN at 4 defined time points throughout the cardiac cycle for single and double rings at the annulus and STJ (mean ± standard deviation). ED: end-diastole; ES: end-systole; LC: left coronary sinus; LN: left/non-coronary segment; LR: left/right-coronary segment; MD: mid-diastole; MS: mid-systole; NC: non-coronary sinus; RC: right coronary sinus; RN: right/non-coronary segment; STJ: sinotubular junction.