Costs and effectiveness of prehospital thrombolysis need to be clear

Editor—Pedley et al provide further evidence that paramedical staff providing prehospital thrombolysis for acute myocardial infarction is feasible and reduces the treatment delay.¹ However, no cost data were presented.

The authors say that two extra lives might be expected to be saved per 100 patients treated. It is unclear how this estimate was derived. We suspect that this is from the meta-analysis by Boersma et al.² Importantly, this health benefit of a one hour reduction in the treatment delay must be within three hours from symptom onset. Pedley et al describe collecting times of onset of symptoms but do not present their results. This is an important omission as the mortality benefit of thrombolysis is directly related to treatment delay from the time of the onset of symptoms. The health benefit of a one hour decrease in treatment delay will be considerably reduced if the total delay is longer than three hours.²

Evidence from audit that the care pathway for acute myocardial infarction is achieving the maximum possible health benefit is needed before considering introducing a prehospital thrombolysis service.

We believe that the emphasis of research should now move to establishing and evaluating cost effective models of care for prehospital thrombolysis rather than feasibility studies. Proposals for a prehospital thrombolysis service will be competing against other healthcare interventions in the prioritisation process of primary care trusts. Therefore the costs and effectiveness of such a service will need to be clear and robust to achieve long term funding.