The slippery slope.

The achievement of adequate and prompt myocardial reperfusion in acute myocardial infarction (AMI) is the most important determinant of recovery of ventricular function at follow-up. This explains the great attention given to the so-called no-reflow phenomenon, which is associated with extensive myocardial damage and a high prevalence of future cardiac events after AMI. The no-reflow phenomenon has been clinically demonstrated first by the thrombolysis in myocardial infarction (TIMI) trial and subsequently studied by other invasive imaging methods such as intra-coronary myocardial contrast echocardiography, intra-coronary Doppler ultrasound, TIMI frame count, and myocardial blush grade. Recently, noninvasive techniques as intravenous myocardial contrast echocardiography (MCE) and transthoracic coronary Doppler ultrasound have been introduced to detect and monitor dynamic changes of reperfusion over time. Other non-imaging methods are based on ST segment resolution at serial ECG monitoring and enzymatic washout curve. The paper by Yawakura et al., published in this issue of the European Heart Journal, replicates previous experience using intra-coronary Doppler ultrasound, to demonstrate that resting transthoracic coronary Doppler ultrasound may disclose a typical pattern of no-reflow, which is characterised by low peak systolic flow velocity, high diastolic peak flow velocity and short deceleration