Draft guidance from NICE paves way for next-generation cardiac CT scanners  

15 September 2011

Draft guidance from NICE’s Diagnostics Assessment Programme on four new-generation cardiac CT scanners has been issued for public consultation (till 3 October 2011).

The provisional recommendations support the use of Somatom Definition Flash CT scanner (Siemens AG Healthcare), Aquilion ONE (Toshiba Medical Systems), Brilliance iCT (Philips Healthcare) and Discovery CT750 (GE Healthcare) in the NHS in England for people with suspected or known coronary artery disease in whom imaging is difficult with earlier generation CT scanners.

Coronary artery disease, which is characterised by narrowing of the coronary artery, leads to reduced blood flow to the heart which can result in angina and myocardial infarction. In 2007, coronary artery disease was estimated to have caused 91,000 deaths in the UK. CT scans are performed to evaluate the arteries of the heart, and can also be used to assess the function of the heart, the anatomy of the heart, and the degree of coronary calcification in the heart.

The recent NICE clinical guideline on chest pain of recent onseti recommends CT coronary angiography and invasive coronary angiography to assess the state of arteries and identify significant narrowing in people with an estimated probability of coronary artery disease of 10-29% and a calcium score of 400 or less.

 People with a calcium score above 400 are considered difficult to image using earlier generation CT technologies. Other reasons that make CT imaging difficult are obesity, arrhythmias (irregular heart beat), high heart rates (above 70 beats per minute) or previous coronary stents or bypass grafts.

The new generation cardiac CT scanners have advanced technical features which can overcome these difficulties. These include the ability to acquire images much faster than earlier generation CT scanners, better image quality and reduced radiation doses.

The draft NICE guidance recommends the use of new generation CT scanners for first line imaging of the coronary arteries in people with suspected stable coronary artery disease who are difficult to image with earlier generation CT scanners and whose estimated probability of having coronary artery disease is 10-29%.

In addition, the draft guidance recommends their use in people with known coronary artery disease for first line evaluation of disease progression to establish the need for revascularisation where imaging with earlier generation CT scanners is difficult.

Professor Carole Longson, NICE Health Technology Evaluation Centre Director, said: “The independent Diagnostics Advisory Committee concluded that new generation cardiac CT scanners are good value for money for hard to image patients instead of proceeding directly to initial angiography. The Committee acknowledged that, from a patient perspective, a non-invasive cardiac diagnostic test is preferable to invasive coronary angiography because of the risks associated with this type of test.

"The provisional recommendations on the use of this important new technology are now open for consultation and we look forward to receiving comments from health professionals, industry and patient groups. In particular we would welcome the opportunity provided by this consultation to provide comments in the context of the existing NICE clinical guidelines on diagnosing chest pain and the management of stable angina.”

More information

More information on the diagnostics draft guidance consultation for CT scanners for cardiac imaging is available at http://guidance.nice.org.uk/DT/3.
The consultation closes on 3 October 2011.