Continuous multilead ST-monitoring identifies patients with unstable coronary artery disease who benefit from extended antithrombotic treatment

Abstract

Aims: Prolongation of anticoagulant treatment might reduce subsequent cardiac events in patients with unstable coronary artery disease. Multilead ST-segment monitoring identifies patients with a high risk of adverse outcome. The aim was to assess the value of multilead ST-monitoring in prospectively identifying patients who respond to extended anticoagulant treatment with low-molecular weight heparin when treated by a primarily non-invasive strategy.

Methods and results: In this substudy of the FRISC II trial, ST-monitoring with a continuous 12-lead ECG or vectorcardiography was performed for 24 h in 629 patients with unstable coronary artery disease randomized to receive either the low-molecular weight heparin dalteparin, or placebo for 3 months after at least 5 days' dalteparin treatment in all patients. Ischaemic episodes were detected in 34% during ST-monitoring. In the group with ischaemic episodes, the extended dalteparin treatment was associated with a lower rate of death, myocardial infarction, or revascularization (35.2% vs 53.4%, relative risk reduction: 34%, P=0.01). In patients without ischaemic episodes, long-term dalteparin treatment had no effect.

Conclusions: In patients with unstable coronary artery disease treated primarily with a non-invasive strategy, ischaemic episodes revealed while on multilead ST-monitoring identifies patients who benefit most from extended treatment with anticoagulants.