A Diagnostics & Imaging Week

Dutch researchers who analyzed more than 4,000 men and women over age 55 to see how many heart attacks went undiagnosed at the time they occurred, found that the figure was more than four in 10.

The results come from an analysis of a large proportion of the men and women involved in the Rotterdam Study, a prospective population study investigating chron-ic disabling diseases. A total of 5,148 participants with no evidence of prevalent myocardial infarction (MI) were enrolled from 1990 to 1993.

Their report was published in the Feb. 14 edition of Euro-pean Heart Journal. The authors, who are from the department of epidemiology and biostatistics at Erasmus Medical Center (Rotterdam, the Netherlands), say their findings suggest that the role of ECGs in existing cardiovascular prevention programs should be evaluated.

The patients assessed by the researchers underwent a baseline ECG and examination. Data from clinically recognized MIs (i.e., heart attacks that were formally diagnosed) over the years that followed were analyzed. The 4,187 of the total who had at least one repeat ECG during two rounds of follow-up assessment between 1993-96 and 1997-99, were analyzed for clinically unrecognized MI.

Senior author Dr. Jacqueline Witteman, associate professor of epidemiology, said, "Over our median follow-up time of more than six years, we found an incidence rate of nine heart attacks per 1,000 person-years. There were around 12 heart attacks per 1,000 person-years in men [8.4 recognized and 4.2 unrecognized] and around seven per 1,000 person-years in women [3.1 recognized and 3.6 unrecognized]. Additionally, in men as well as in women, there was one sudden death per 1,000 person-years."

Overall, she said, 43% of the total heart attacks had been clinically unrecognized – one-third of the male heart attacks and more than a half of the female heart attacks.

Witteman said that in each of the age bands between 55 and 80, men had a higher incidence of recognized MIs than women and a similar incidence of unrecognized MIs. This provided the evidence that heart attacks are less often recognized in women, she said, irrespective of characteristics that have previously been associated with MI.

Co-author Dr. Eric Boersma, associate professor of clinical cardiovascular epidemiology, said that although the study was conducted in the Netherlands, the results were likely to be equally applicable to any other developed country.

He said that in most developed countries, cardiovascular prevention programs are installed, which aim to identify high-risk individuals on the basis of classical risk factors, including smoking and obesity, and co-conditions, such as diabetes mellitus. "Our findings indicate that these programs might be enriched with an ECG," Boersma said.

Aussie firm broadens test effort

Ambri Ltd. (Sydney, Australia) has reported additional details about its recently announced program to develop a rapid diagnostic test chip for human respiratory infections, including a test for avian flu.

The company has shown in a laboratory test bed system that three different assays can be performed simultaneously on its current biosensor chip configuration. It said the new chip configuration is on an inexpensive plastic base and fits the existing laboratory test bed reader developed by Ambri.

The common flu A (influenza type A) was one of the tests demonstrated in the company's 16-sensor diagnostic test chip.

Ambri said it is extending the ICS biosensor chip development program to include avian influenza type H5N1. The near-term objective of the strategy, it said, is to develop a prototype of a chip that would be the basis of a product to simultaneously detect in a nasal or throat swab the presence of any one of three influenza viral types.

"These viral infections all begin with very similar symptoms," Ambri said, "and it is important to rapidly distinguish serious infections such as bird flu from common influenza such as flu A or flu B."

CEO Roman Zwolenski said: "Progressing down this development path with multiple ‘yes' or ‘no' tests on the same chip gives Ambri the best chance of attracting a commercial partner to incorporate the ICS biosensor technology in a marketable product."

Ambri said it intends to use a new 16-sensor ICS configuration for the triple-test respiratory diagnostic chip, which it expects to be able to gold-imprint and fully assemble in house.

"This gives us flexibility to advance quickly with the product prototyping," Zwolenski said.

600th LightSpeed VCT for GE

GE Healthcare (Waukesha, Wisconsin) said recently that it has reached the 600th global installation of its LightSpeed VCT, the world's first volume computed tomography (CT) system. The company said the LightSpeed VCT is the fastest-selling product in its history.

The 600th global shipment of VCT will be received by Akita University, one of the largest universities in the Tohoku region in Japan. The university will install both the LightSpeed VCT and LightSpeed VCT Select.

GE Healthcare said cardiac CT has been recognized as one of the biggest breakthroughs in healthcare.

LightSpeed VCT clinical applications include:

• 5-Beat Cardiac, which the company calls "a comprehensive view of the heart and coronary arteries with submillimeter resolution in five seconds." It said this coverage helps reduce beat-to-beat variability, "resulting in more robust, repeatable procedures, as well as greater vessel visualization and shorter breath holds for sick patients."
• Triple Rule-Out, the ability to help clinicians rule out (or in) the three most life-threatening critical conditions in chest pain – aortic dissection, pulmonary embolism and coronary artery disease – in a single scan.
• Stroke WorkUp, the ability to dynamically acquire both anatomy and perfusion/blood flow to the brain in a single scan.

GE Healthcare said 34 of its VCT systems have been delivered to medical sites in Japan to date.

MSI reports Middle East HIV test orders

Medical Services International (MSI; Edmonton, Alberta) said it received orders for 1.5 million VScan HIV test kits from two Middle East countries as a result of its participation in the recent Dubai Medical Conference. It said those orders would generate revenue of approximately $3.5 million U.S. over the next 15 months.

MSI said it is to deliver the test kits in 12 equal orders over a period of one year, starting May 1. It added that its distributor in the Middle East is negotiating with several other countries and expects to receive additional orders that will be in excess of 1 million HIV test kits.