1 Recommendations

1.1

KardiaMobile 6L can be used in psychiatric services as an option to measure cardiac QT interval for adults having or about to have antipsychotic medication while more evidence is generated only if:

A repeat QT interval measurement using a 12‑lead electrocardiogram (ECG) device is offered to:
- women with a corrected QT interval (QTc) longer than 470 milliseconds
- men, trans people having hormone treatment, and intersex people who have QTc longer than 440 milliseconds
- people who have a follow-up ECG with more than a 50‑millisecond increase in QTc.
  
  For trans people not having hormone treatment, use the QTc threshold for their sex registered at birth.
Training for healthcare professionals on recording an ECG, and measuring and interpreting QT interval is provided.
People are offered information about why this testing is done and why testing may be repeated using a 12‑lead device after it has been measured using KardiaMobile 6L.

1.2

The technology developers must confirm that agreements are in place to generate the evidence (as outlined in NICE's evidence generation plan) and contact NICE annually to confirm that evidence is being generated and analysed as planned. NICE may withdraw the guidance if these conditions are not met.

1.3

At the end of the evidence generation period (3 years), the technology developers should submit the evidence to NICE in a form that can be used for decision making. NICE will review the evidence and assess if the technologies can be routinely adopted in the NHS.

Evidence generation

1.4

More evidence needs to be generated on:

the accuracy of KardiaMobile 6L to measure QT interval in adults having or about to have antipsychotic medications
how the test result affects clinical decision making
how long the testing takes, who interprets the results and how often the test is repeated using a 12‑lead device
patient preferences
how long it takes before antipsychotic medication is started
how many adults who need an ECG to measure QT interval have one
how common prolonged QT is in adults having antipsychotic medication.

Potential benefits of early access

Unmet need: Detecting cardiac abnormalities such as prolonged QT interval in adults having antipsychotic medication is important because some antipsychotics can prolong the QT interval and lead to severe cardiac events. QT interval is usually measured using a 12‑lead ECG device. This needs the person to partially undress and use conductive stickers or gel on the skin which can cause reluctance and distress. Therefore, QT interval is not always measured before people start having antipsychotic medication or there could be a delay starting antipsychotic medication.
Clinical: Detecting prolonged QT interval can inform choice of therapy, dosing, whether to stop therapy, and potentially avoid severe cardiac events.
Service user preferences: KardiaMobile 6L allows ECG recording with less need for undressing and without using conductive stickers or gel. It can be used during a routine home visit by a community health professional. This may reduce stress and anxiety.
Care pathway: KardiaMobile 6L has the potential to ensure timely ECG testing is available for all which could help adults having antipsychotic medication get faster access to safe and effective antipsychotic treatment.

Managing the risk of early access

Accuracy: There may be some differences in results from measuring a QT interval with KardiaMobile 6L compared with a 12-lead ECG. To reduce the potential effect of false negatives, a QT interval longer than the relevant specified threshold in section 1.1 should be verified using a 12‑lead device. More evidence should be collected on the diagnostic accuracy of using KardiaMobile 6L to measure QT interval in adults having or about to have antipsychotic medications.
Test interpretation: How accurate the ECG interpretation is (measuring QT length, calculating QTc, and deciding whether QT is prolonged) may differ between professionals in different settings. Training for healthcare professionals on recording an ECG and measuring and interpreting QT interval should be provided.
Service user preferences: QT interval measurement should be offered to people at a place and time they can attend and in a way that they feel comfortable. Information should be offered about why QT interval measurement is important. Further evidence should be collected on service users preferences for how they have their QT interval measured.

The evidence generation plan gives further information on the prioritised evidence gaps and outcomes, ongoing studies and potential real-world data sources. It includes how the evidence gaps could be resolved through real-world evidence studies.