Specialist commentator comments

Comments on this technology were invited from clinical experts working in the field. The comments received are individual opinions and do not represent NICE's view.

None of the specialist commentators were familiar with the technology or had used the CADScor system before.

Level of innovation

All experts agreed that the technology is novel in its concept and design, and none of the commentators were aware of any comparable technologies currently in clinical use within the NHS. One commentator noted that although acoustic detection of flow-limiting coronary artery disease (CAD) is a novel concept, other acoustic devices for non-invasive detection of CAD exist.

Potential patient impact

The non-invasive, rapid rule out of CAD, leading to a reduced need for more complex investigations in patients with a low likelihood of CAD, was the main benefit identified by specialists. This was said to reduce the exposure of individuals to ionising radiation and to the risks of invasive procedures. One commentator added that the technology may provide greater confidence of rule out in low-risk patients who present with atypical or non-specific symptoms. One commentator thought the benefits to patients were limited, noting that obstructive coronary artery disease would not be definitively ruled out and people with continuing symptoms may need to have further investigations, regardless of a low CAD-score. Most commentators said the technology was unlikely to lead to substantial changes to current practice or clinical outcomes, but may shorten the pathway for some patients by reducing the need for CT coronary angiography (CTCA) and invasive coronary angiography (ICA). Most of the commentators agreed that the technology would be of most benefit for patients presenting with suspected symptoms with a very low or low to intermediate risk of CAD.

Potential system impact

The potential to release resources and provide cost-savings by reducing the need for more complex investigations, such as CTCA and ICA, was identified as a key benefit to the healthcare system. The potential to reduce the use of ionising radiation was also identified as a benefit by 1 commentator. Apart from the initial upfront cost associated with the purchase of the system, most commentators agreed that use of the CADScor system may provide savings to the NHS provided it led to fewer complex and costly tests being done. The resource impact of adopting the technology included the purchase of hardware and disposables as well as the additional staff time to do the test, but should reduce the burden on CT services and other investigational pathways for chest pain. Commentators noted the technology could be used as an outpatient hospital procedure, in accident and emergency departments or in the community setting to avoid unnecessary trips to hospital, but is unlikely to shift care from secondary to primary setting. Most commentators agreed that the technology would be an addition to standard care but may replace additional investigations (CTCA or invasive coronary angiography [ICA]) in a proportion of patients. None of the commentators were aware of any major changes to facilities or infrastructure needed to adopt the technology. Staff training on how to use the device and interpret results was identified as a need by 4 of the specialists.

General comments

All commentators noted that the CADScor system is not used in the NHS. None of the commentators were aware of any safety concerns surrounding the technology, although 1 noted that an allergy to the disposable chest pads may happen in some patients. Most commentators were not aware of any issues with the usability of the technology, but 1 said that it is unclear if obesity or lung disease (which could obscure or confuse the acoustic signal) affect the sensitivity and specificity of the test. The main barrier to adoption identified by most commentators was the lack of randomised controlled data from an NHS setting; 2 commentators stated that at present the available evidence is not enough to support the use of the technology in routine clinical practice. Commentators highlighted that existing data only relates to Danish experience in a low-risk cohort of patients, adding that validation in a large and diverse UK population (that is, different family origins, high BMI, older or younger patients, varying levels of disease severity and stenosis) is needed before adoption. Longer-term data surrounding the clinical and cost implications of adopting the technology into standard NHS practice, including the effects on resource utilisation and the time to diagnosis, would also be useful. Specialists highlighted that the CADScor system may be unable to identify premature atheroma, limiting its role as a surrogate for future cardiovascular risk reduction. One commentator thought the test may theoretically miss cases of atherosclerosis that are only flow-limiting in a dynamic state, because of the test being done under resting conditions. According to 1 commentator, NHS trusts do not currently use CAD risk scoring algorithms, adding that some CAD risk scoring algorithms have historically over predicted CAD and are becoming obsolete, with a preference towards using clinical symptom evaluation and an ECG alone (as recommended in NICE's guideline on chest pain of recent onset: assessment and diagnosis).