What is the recommended approach for patients with non-diagnostic initial ECG and symptoms consistent with ACS?
Serial ECGs (eg, 15- to 30-minute intervals during the first hour) should be performed to detect ischemic changes. Furthermore, serial cardiac troponin I or T levels should be obtained at presentation and 3 to 6 hours after symptom onset. Additional troponin levels should be obtained beyond 6 hours after symptom onset in patients with normal troponin levels on serial examination when changes on ECG and/or clinical presentation confer an intermediate or high index of suspicion for ACS. Risk scores should also be used to assess prognosis in patients with NSTE-ACS. For patients with non-diagnostic initial ECG and intermediate/high risk of ACS, it is reasonable to obtain supplemental electrocardiographic leads V7 or consider continuous monitoring with 12-lead ECG.