HeartStart MRx Monitor/Defibrillator –possible failure to deliver defibrillation therapy

(Philips Healthcare) May fail to deliver defibrillation therapy in either “Manual Defib”, “AED” or “Sync Cardioversion” mode. (MDA/2013/052)

CAS deadlines

Action underway: 18 July 2013, Action complete: 1 August 2013

Note: These deadlines are for identification of device, staff to be aware and availability of a backup.


HeartStart MRx Monitor/Defibrillator

HeartStart MRx Monitor/Defibrillator.

Manufactured by Philips Healthcare.

Model numbers: M3535A, M3536A, M3536J, M3536M, M3536MC, M3536M2, M3536M4, M3536M5, M3536M6.

Affected serial numbers from US00100100 to US00565942 inclusive.


The Philips HeartStart MRx Monitor/Defibrillator may fail to deliver defibrillation therapy in either “Manual Defib”, “AED” or “Sync Cardioversion” mode.

If this occurs, the MRx will simultaneously display the following:

  • Flat line ECG.
  • “Device error. Service required” message.
  • “Shock Equip Malfunction” INOP.
  • Red “X” in the RFU indicator.

If the problem occurs it can impact either cardioversion or defibrillation therapy within the specified modes.  Pacing is not affected.


  • Identify affected devices.

Ensure that:

  • staff are aware of the recommended actions in the FSN (43Kb);
  • you have ready access to an alternative defibrillator until the software upgrade has been undertaken;
  • Philips contact you to arrange installation of the software upgrade.

Action by

All medical, nursing and technical staff involved in the use and maintenance of these devices.


This MDA has been sent to:

  • Care Quality Commission (CQC) (headquarters) for information
  • HSC trusts in Northern Ireland (chief executives)
  • Local authorities in Scotland (equipment coordinators)
  • NHS boards and trusts in Wales (chief executives)
  • NHS boards in Scotland (equipment coordinators)
  • NHS England area teams for information
  • NHS trusts in England (chief executives)

Onward distribution

Please bring this notice to the attention of relevant employees in your establishment. 
Below is a suggested list of recipients.  

CAS and SABS (NI) liaison officers for onward distribution to all relevant staff including:

  • A&E departments
  • All clinical departments
  • All clinical staff
  • All wards
  • Ambulance services directors
  • Ambulance staff
  • Biomedical engineering staff
  • Cardiology departments
  • Cardiothoracic departments
  • Clinical governance leads
  • EBME departments
  • Health and safety managers
  • Maintenance staff
  • Medical directors
  • Nursing directors
  • Resuscitation officers
  • Risk managers

Independent distribution

Establishments registered with the Care Quality Commission (CQC) (England only) 
This alert should be read by:

  • Hospitals in the independent sector
  • Independent treatment centres

Please note: CQC and OFSTED do not distribute these alerts. Independent healthcare providers and social care providers can sign up to receive MDAs directly from the Department of Health’s Central Alerting System (CAS) by sending an email to: safetyalerts@dh.gsi.gov.uk and requesting this facility.

Manufacturer contact


Philips Customer Care Service Centre
Tel:    0870 532 9741

Email:  ph.pmuk.support@philips.com


If you have any comments or feedback on this Medical Device Alert please email us at: dts@mhra.gov.uk.


If you are in England, please send enquiries about this notice to the MHRA, quoting reference number MDA/2013/052 or 2013/005/007/081/025.

Technical aspects

Paul Sandhu or Enitan Taiwo
Medicines & Healthcare Products Regulatory Agency
Floor 4
151 Buckingham Palace Road
London SW1W 9SZ
Tel:    020 3080 7266 / 7122
Fax:   020 8754 3965

Email:    paul.sandhu@mhra.gov.uk or enitan.taiwo@mhra.gov.uk

Clinical aspects

Jonathan Plumb
Medicines & Healthcare Products Regulatory Agency
Floor 4
151 Buckingham Palace Road
London SW1W 9SZ
Tel:    020 3080 6648
Fax:   020 8754 3965

Email:    jonathan.plumb@mhra.gov.uk

How to report adverse incidents

Please report via our website: Reporting adverse incidents involving medical devices
Further information about CAS can be found on the CAS website

Northern Ireland

Alerts in Northern Ireland will continue to be distributed via the NI SABS system.

Enquiries and adverse incident reports in Northern Ireland should be addressed to:

Northern Ireland Adverse Incident Centre
Health Estates Investment Group
Room 17
Annex 6
Castle Buildings
Stormont Estate
Dundonald BT4 3SQ
Tel: 02890 523 704
Fax: 02890 523 900

Email: NIAIC@dhsspsni.gov.uk

How to report adverse incidents in Northern Ireland

Please report directly to NIAIC, further information can be found on the NIAIC website
Further information about SABS can be found on the SABS website


Enquiries and adverse incident reports in Scotland should be addressed to:

Incident Reporting and Investigation Centre
Health Facilities Scotland
NHS National Services Scotland
Gyle Square
1 South Gyle Crescent
Edinburgh EH12 9EB
Tel: 0131 275 7575
Fax: 0131 314 0722

Email: nss.iric@nhs.net


Enquiries in Wales should be addressed to:

Improving Patient Safety Team
Medical Directorate
Welsh Government
Cathays Park
Cardiff CF10 3NQ
Tel: 029 2082 3922

Email: Haz-Aic@wales.gsi.gov.uk

Download documents

Medical Device Alert: HeartStart MRx Monitor/Defibrillator manufactured by Philips Healthcare (MDA/2013/052) (73Kb)

Published 17 December 2014