Sao Paulo STEMI network

Acute myocardial infarction is responsible for the majority of deaths in São Paulo, Brazil. The emergency services as well as access to hospitals are rather scarce in the peripheries, being more concentrated in the central areas of the city, and this can cause delays in diagnosis and treatment of myocardial infarction.

The São-Paulo STEMI Network study was a pilot investigation to monitor clinical outcomes of patients with ST-elevation acute myocardial infarction (STEMI) presenting via ambulance or emergency departments that were part of the STEMI Network.

The STEMI Network is a structured network involving a tertiary hospital, Hospital São Paulo, 126 ambulances of the Emergency Mobile Health Care Service (abbreviation in Portuguese: SAMU) covering the entire São Paulo municipal area, and 4 municipal emergency departments. The aim of the STEMI Network was to standardise treatment and reduce delays for STEMI patients.

 

In 2010, the STEMI Network was implemented in São Paulo to standardise treatment for STEMI patients, with steps taken to ensure the following:

  • Rapid clinical diagnosis
  • Immediate ECG for any patient with chest pain (including reading support from an ECG central office if necessary)
  • Immediate definition of management (primary percutaneous coronary intervention [PCI] for anticipated transfers to catheterisation laboratory 90 min)
  • Immediate use of therapeutic adjuvants
  • Immediate transfer to a tertiary hospital, even if stable

 

Flowchart

 Flowchart showing components and workflow of STEMI Network in Sao Paulo

From January 2010 until June 2011, the STEMI Network study assessed 205 consecutive patients, with no exclusions, who underwent the entire process, i.e. diagnosis to transfer to the tertiary hospital with a catheterisation laboratory.

As expected, due to the distances between the centres involved in the STEMI Network and the logistical problems of transferring patients in São Paulo, only 38 patients (18.5%) were transferred for primary PCI, although it was only actually performed in 22 patients; of the remaining 16 patients, 13 had no intervention and 3 did not undergo cardiac catheterisation. The rest of the patients (81.5%, n=167) that were not referred for primary PCI received a thrombolytic agent, in almost all cases tenecteplase. Of these patients, 25.7% underwent rescue PCI and the others underwent elective cardiac catheterisation with stent implantation if necessary.

There were 14 in-hospital deaths (6.8%), almost all involving elderly patients or patients with low cardiac output.

A specific comparison of mortality in the emergency department of Hospital Ermelino Matarazzo before and after the implementation of the STEMI Network was performed:

  • In 2009, before the implementation of the STEMI Network, mortality for 88 STEMI patients was 26.1%
  • In 2010-2011, after the implementation of the STEMI Network, mortality for 65 patients that initiated treatment at the Hospital Ermelino Matarazzo and completed it at the Hospital São Paulo was only 6.1%
  • The results of the STEMI Network confirm that implementation of an organised STEMI network can improve patient outcomes, and in particular, reduce in-hospital mortality.
References: 
  1. Caluza AC, et al. ST-Elevation myocardial infarction network: systematization in 205 cases reduced clinical events in the public health care system. Arq Bras Cardiol 2012;99(5):1040-1048.
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