It is hypothesised that the MyoVista wavECG has the potential to show non inferior sensitivity and specificity compared to the current heart failure pathway screening tools of BNP/NT-proBNP and 12 lead resting ECG, but has the advantage of providing a single, familiar, inexpensive point of care test which provides point of care results and can act as a prescreen, or in circumstances replacement to BNP/NTpro-BNP testing, and eliminate a proportion of the unnecessary testing and echo referrals.

A comparative performance analysis of the modalities will form the basis for the study with subsequent reporting on the financial impact and societal benefits of any potential pathway change.

This is a multi-center, non-interventional, single arm, non-inferiority clinical study of the MyoVista wavECG ability to identify primary care patients for referral to secondary care for diagnosis of heart failure (as defined by BSE (British Society of Echocardiography) guidelines for echo), in direct comparison to BNP/NT-proBNP. The study will be conducted at a maximum of 10 investigational secondary care sites within the United Kingdom, and some/all referring primary care centres for each site. Study subjects presenting at primary care with shortness of breath, risk factors for and/or suspicion of heart failure will be referred to secondary care for 2D transthoracic echocardiogram based on borderline and abnormal BNP/NT-proBNP results as part of the current heart failure pathway as defined by the NICE (National Institute for Health and Care Excellence) guidelines, with the MyoVista wavECG used for the conventional 12 lead ECG reporting and comparison purposes only. MyoVista wavECG results will not be used in the diagnosis of a patient, and/or for the basis of a patient referral to echocardiography for the study duration. In commercial use the MyoVista wavECG will be intended for use in a population of patients being considered for such a referral by providing CWT (Continuous Wavelet Transform) and AI (Artificial Intelligence) derived informatics surrounding an overall summary of left ventricular relaxation abnormalities (High Negative, Negative, Borderline, Positive and Highly Positive). The design of this study will allow for an appropriate evaluation of safety and effectiveness for that population.

The study duration will consist of a single visit for all study subjects, after which the subject's participation in the trial will conclude unless longitudinal study inclusion criteria met and agreed at enrollment (Normal BNP/NT-proBNP, MyoVista wavECG result Negative, Borderline, Positive, Highly Positive).

All study subjects will provide written informed consent for the procedures consistent with the study protocol.

Inclusion Criteria:

1. Subjects presenting with shortness of breath and risk factors for and/or suspicion of having early-stage heart failure during initial clinical assessment.
2. Informed Consent - The subject provides written informed consent using an Informed Consent Form that is reviewed and approved by the site's Institutional Review Board (IRB).
3. Sinus rhythm - Conventional ECG results show a sinus rhythm and no other contraindicated rhythm abnormalities (see exclusions below)
4. Age - Subject is ≥18 years of age

Exclusion Criteria:

1. Acute Disease - The subject has current acute coronary syndrome, decompensated heart failure, stroke, or previous history of MI.
2. Prior Cardiac Procedures - The subject has received any prior cardiac interventions or surgical therapeutic procedures relating to cardiac abnormalities: valve replacement, pacemaker implantation, coronary artery bypass grafting (CABG), heart transplant, ablation, coronary stent placement, etc.
3. Rhythm Abnormalities - Conventional ECG results indicating a lack of sinus rhythm and/or automatic heart failure pathway RULE IN rhythms including active atrial fibrillation or atrial flutter, left anterior fascicular block, left and/or right bundle branch block
4. Pregnancy - The subject self declares pregnancy at the time of the study testing
5. Chest deformities - The subject has chest deformities that interfere with accurate measurement of ECG (either conventional or wavECG)
6. Measurement Interference - Subjects with central nervous system or musculoskeletal abnormalities that may interfere with accurate acquisition of ECG and/or echocardiogram measurements.
7. Study Participation - The subject is enrolled in another clinical study that may interfere with MyoVista or echocardiogram measurements. Exceptions to this may be approved prior to enrollment.

Subject recruitment will include individuals presenting with shortness of breath and with risk factors for and/or suspicion of heart failure, who are to be screened as per the UK National Institute for Care and Clinical Excellence (NIICE) guidelines using a conventional 12 lead resting ECG, BNP/NT-proBNP and referred for echocardiography as part of their standard care.