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Coronary artery blood flow is influenced by various factors including vessel geometry, hemodynamic conditions, timing in the cardiac cycle, and rheological conditions. Multiple patterns of disturbed coronary flow may occur when blood flow separates from the laminar plane, associated with inefficient blood transit, and pathological processes modulated by the vascular endothelium in response to abnormal wall shear stress. Current simulation techniques, including computational fluid dynamics and fluid-structure interaction, can provide substantial detail on disturbed coronary flow and have advanced the contemporary understanding of the natural history of coronary disease. However, the clinical application of these techniques has been limited to hemodynamic assessment of coronary disease severity, with the potential to refine the assessment and management of coronary disease. Improved computational efficiency and large clinical trials are required to provide an incremental clinical benefit of these techniques beyond existing tools. This contemporary review is a clinically relevant overview of the disturbed coronary flow and its associated pathological consequences. The contemporary methods to assess disturbed flow are reviewed, including clinical applications of these techniques. Current limitations and future opportunities in the field are also discussed.

Aims: The use of treadmill stress echocardiography (SE) for the diagnosis of nascent pulmonary hypertension (PH) has been hampered by a lack of well-defined, post-exercise pulmonary artery systolic pressure (PASP) values across representative age groups in a normal cohort., Methods and Results: Five hundred and eleven subjects (mean age: 53 ±14, 68% female) with normal resting PASP were included in the study. All participants performed treadmill exercise using the Bruce protocol to a high level of perceived exertion. PASP was calculated before and immediately after exercise using Doppler assessment of tricuspid regurgitation. For the cohort, post-exercise PASP was 39 ± 7 mmHg (range: 23-64 mmHg) representing an increase of 11 ± 6 mmHg (44%) from resting values (P < 0.001). The 95th centile values for post-exercise PASP were calculated for the following age cohorts: <30 years; 46 mmHg, 31-50 years; 50 mmHg, 51-70 years; 52 mmHg, >70 years; 53 mmHg. There was a modest independent correlation between post-exercise PASP and (i) increasing age and (ii) resting PASP (r2 = 0.35 and 0.49, respectively, P = 0.01)., Conclusion: An increase of post-exercise PASP was seen in all patients undergoing SE in this study. Age was directly correlated with post-exercise PASP. Using normative data from healthy controls, treadmill SE-derived post-exercise PASP may be a useful adjunct in the diagnosis of PH., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions, please email: journals.permissions@oup.com.)