In patients with acute transient myocardial ischaemia, changes in left ventricular filling produce alterations in transmitral diastolic flow velocity and isovolumic relaxation time. In this study a scoring system derived from isovolumic relaxation time and indices from transmitral flow velocity was used to evaluate perioperative transient myocardial ischaemia. Fifty three patients with known coronary artery disease or at risk were studied. Ischaemic events were assessed using Doppler transoesophageal echocardiography midoesophageal left ventricular four-chamber view planes. Diastolic Doppler ratios of peak early to atrial peak (E/A), deceleration time, deceleration rate and isovolumic relaxation time were scored using standard methods. An evaluation of peri-operative ischaemic events could be important for patients with a nonischaemic cause for abnormal segmental wall motion, as the use of a two-dimensional scoring system has limitations. Acute changes in the Doppler ratio of peak early to atrial peak must be interpreted cautiously during surgery. Diastolic dysfunction commonly occurs during ischaemia and recognition of this may alter the approach to monitoring as well as to treatment.