Continuous ST monitoring: A bedside instrument? A report from the Assessment of the Safety of a New Thrombolytic (ASSENT 2) ST Monitoring Substudy

Background Continuous ST monitoring has during the past decade become widespread in coronary care units (CCU) and is now even recommended by international task forces to survey patients with acute coronary syndromes. ST monitoring has also been shown to be a well-validated technology to predict prognosis and coronary artery patency in patients with acute ST-elevation infarction. However, all evaluations in previously presented trials have been made inside a core laboratory by specially trained personnel. Methods In the Assessment of the Safety and Efficacy of a New Thrombolytic (ASSENT 2) ST-monitoring substudy, 448 patients with ST-elevation infarction from 22 hospitals were monitored by vectorcardiography. The local nurse responsible for the patient made an evaluation of the ST trend curve. This was compared with a blinded core laboratory evaluation and examined versus 30-day mortality. Results No significant differences were found between the local and central evaluations of ST-segment recovery. The accuracy of the local evaluation, compared with the central one, in deciding whether patients had ≥50% ST-segment recovery at 60 or 90 minutes was >90%. A large low-risk group (30% of the patients) with 0.8% 30-day mortality could be identified by the local evaluation. Conclusions ST monitoring with vectorcardiography can accurately be done in the clinical setting. The local evaluation was as least as accurate as the core laboratory evaluation in predicting prognosis. (Am Heart J 2001;142:58-62.)