The Alternans Sensor Kit Assembly is a sealed kit that contains the components necessary for conducting a Microvolt Twave Alternans test.

Some kits contained a component with expiration date prior to the date of expiry on the outside of the kit. The user receives feedback of potential unreliable results at several stages during the test process, so any risk of unreliable results is low.

The Alternate Sensor Kit Assembly P/N 203270209 may contain a pouch of standard ECG electrodes with an expiry date which is earlier than the expiration date on the outside label of the kit. All customers were sent a letter dated April 23, 2010 with information that included instructions for returning the kits. Questions are directed to the company's Quality Manager and Recall Coordinator at phone number 978-654-7625.