300 or more supraventricular ectopic beats in 24 hours. 250 or more ventricular ectopic beats in 24 hours. Ischemia, diagnosed by a sequence of ECG changes that include flat or down sloping ST-segment depression >0.1 mV, with a gradual onset and offset that lasts for a minimum period of 1 minute. Each episode of ischemia must be separated by a minimum duration of at least 1 minute, during which the ST segment returns back to baseline (1x1x1 rule).