In the United States alone, it is estimated by the American Heart Association that over one million people will have a coronary attack this year. Of these, about 700,000 people will have a new attack and 500,000 will have a recurrent attack. In addition to the over one million coronary attacks which are identified, another 175,000 people will have a silent first heart attack which will go unnoticed and will not be diagnosed at the time of occurrence.
When people with symptoms of a coronary attack are brought to an emergency department or other healthcare provider for care, among the tools most commonly used to help diagnose them is a 12-lead electrocardiogram (ECG). The ECG records and analyzes the electrical signals of the heart. Examination of these signals can identify many forms of heart disease including ischemia (insufficient oxygenation of the heart muscle) and myocardial infarction (heart attack due to obstruction of the blood supply). Minimizing the time to diagnosis and treatment is critical in order to avoid permanent injury to the heart that can lead to impaired heart function or death. A common saying for these cases is time is muscle meaning the more time it takes to diagnose and begin treatment, the more heart muscle can be damaged leading to bad outcomes.
3-dimensional patient torso body surface map produced as a result of PRIME ECG technique.
While the 12-lead ECG along with serum biomarkers of cardiac damage such as troponin or creatine kinase MB are among key tools for diagnosis, these tests may not identify the early occurrence of coronary attacks. Studies have shown that in a significant number of cases the 12-lead ECG is unable to provide information needed for early diagnosis because of the location of the injury within the heart. This results in treatment delay and increasing costs while other tests are performed. Attempts to improve the performance of the ECG by adding electrodes (typically right-sided and posterior) have resulted in limited improvement.
Decades of research has demonstrated that the addition of many more sampling sites, or the number of electrodes used on a patients body, can reveal important diagnostic information that can identify problems earlier with greater detail. Receiving this information sooner aids in diagnosis, risk stratification and treatment which saves lives and resources. One such technique which takes advantage of this additional data is body surface mapping (BSM).
According to Susan Cramer, Area Manager for Heartscape Technologies, Inc. a company which has developed PRIME ECG®, a BSM product, “Body surface mapping is an electrocardiographic technique that uses numerous sampling points (electrodes) on a patients anterior and posterior chest. BSM can be used as a complement to standard 12-lead ECG tests providing a more complete visualization of cardiac electrical activity. The output from BSM includes a 12-lead ECG format, an 80-lead ECG format, and a series of color maps superimposed onto a three-dimensional torso image.”
While the benefits of using additional ECG leads has been known for some time, several technical barriers prevented adoption of the process. The first challenge was that the number of individual electrodes needed for BSM could not be easily, quickly or economically placed on patients. Secondly, computers with the power and compactness for use in medical situations which could record and rapidly analyze data had not been available. Lastly, the review and analysis of recorded signals from many more electrode sites was time consuming, complicated and beyond the skill and training of most physicians.
Jamie LaHam, Vice President of Heartscape Technologies commented on how their PRIME ECG® product addressed and overcame these barriers. “Several technological developments have come together which allowed us to create PRIME ECG®. We developed a unique patented electrode vest which can be quickly and easily placed on a patient. The vest contains all the electrodes, anatomically pre-positioned where needed, to collect the data. Also the development of powerful microchips allows our system to record and analyze large volumes of data and create three-dimensional images easily interpreted by medical professionals. Compared to other diagnostic tools, the PRIME ECG® system can achieve an earlier diagnosis and enable earlier treatment for many patients having a myocardial infarction (heart attack).
Nurse places 80-lead ECG vest onto patient for conducting BSM test with PRIME ECG.
Talking about the usefulness of BSM compared to standard 12 lead ECG, Mr. LaHam commented, “Blockage of vessels that nourish the right side and posterior portions of the heart are not easily detected by the 12-lead ECG test. PRIME ECG® has been shown in studies to increase the detection of acute myocardial infarction (AMI) by 40% in a single recording on presentation to the emergency department.” He continued, “Delayed time to detection and intervention is directly linked to increased mortality and morbidity. Only the PRIME ECG® system detects AMI as early as the 12-lead ECG. But not even the 12-lead ECG diagnoses as many marker confirmed AMIs as the PRIME ECG® system.”
Currently, PRIME ECG® is an FDA cleared medical device. It is available and is in use by emergency physicians in several hospitals including Holy Cross Hospital in Ft. Lauderdale, Florida.
Dr. Mark Caputo, Medical Director of Emergency Services at Holy Cross Hospital described his experience with PRIME ECG® as follows, “We introduced PRIME ECG to Holy Cross early this year and have performed approximately sixty PRIME ECGs on patients with chest pain. Although our experience is somewhat limited we have seen some promising results in a few patients. We have been able to detect myocardial ischemia that was not apparent on the traditional routine 12-lead ECG. This has led to more than one case of early intervention (catheter revascularization) based on this new technology. Our physicians have found this technology easy to adopt and incorporate into their practice. Although more data is needed, our early experience is promising.”
Heartscape Technologies which developed and markets the PRIME ECG® product was just formed in 2005. The company has recently initiated marketing of PRIME ECG® and is focusing its current efforts in Florida and the Eastern United States. According to Jamie LaHam, Vice President at Heartscape Technologies, “The company has developed a body of peer-reviewed evidence that supports claims of earlier diagnosis of AMI. Additional studies are underway that will further identify and support the value of this technology. A dedicated sales and support team is being used to approach the hospital emergency department. Many hospitals today have a special focus on providing quality cardiac care. These hospitals often seek to employ the latest technology to give them an edge in the fight against heart disease. We believe PRIME ECG® can provide that edge for many patients.”
He continued, “We believe this technology will become a standard of care for early diagnosis and risk stratification of chest pain patients both in the emergency department and the hospital.”
