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Largest Prospective Study of Microvolt T-Wave Alternans Demonstrates This Technology's Predictive Value for Sudden Cardiac Death in Patients With Preserved Left Ventricular Function After Acute Myocardial Infarction.


1000 Patient Study Supports Microvolt microvolt

one-millionth (10-6) of a volt; abbreviated µV.
 TWA as a Risk Stratifier for this Large Low-Risk Population. Finds 17% Could Possibly Benefit From Therapy Such as Defibrillator Implantation

BEDFORD, Mass. -- Cambridge Heart, Inc. (OTCBB-CAMH) announced today the publication of a study in the Journal of the American College of Cardiology The American College of Cardiology (ACC) is a nonprofit medical association established in 1949 to educate, research and influence health care public policy. The president for the 2006–2007 year is Steven E. Nissen. [1] The organization has 39 chapters in the U.S.  assessing the utility of Microvolt T-Wave Alternans[TM] (MTWA MTWA Microvolt T-Wave Alternans
MTWA Maximum Total Weight Authorised
MTWA Metro Toronto Wrestling Association
MTWA Maximum Takeoff Weight Authorized
) in predicting risk of sudden death among patients who have previously suffered a heart attack (Acute Myocardial Infarction acute myocardial infarction (·kyōōtˑ mī·ō·karˑ·dē· ; MI) yet have preserved cardiac function. This group of patients is outside of the MADIT MADIT Cardiology A clinical trial–Multicenter Automatic Defibrillator Implantation Trial that evaluated the effects of implanted defibrillators–IDs in Pts with CAD at high risk of ventricular arrhythmia  II and SCDHeFT populations as the study included only patients with a left ventricular ejection fraction (LVEF LVEF Left ventricular ejection fraction. See Ejection fraction. ) greater than or equal to 0.40, while the two aforementioned studies involved LVEF en 0.30 and LVEF en 0.35 patients respectively. The results indicate that the MTWA test, using the Cambridge Heart patented Spectral Analytic Method during low heart rate exercise, identifies those patients who are at elevated risk for sudden cardiac death Sudden Cardiac Death Definition

Sudden cardiac death (SCD) is an unexpected death due to heart problems, which occurs within one hour from the start of any cardiac-related symptoms. SCD is sometimes called cardiac arrest.
 and therefore may benefit from implantation of a defibrillator.

The US post-MI population consists of approximately 7,200,000 people. 565,000 new MI patients join this group annually and 225,000 die each year from another MI. Patients with an LVEF greater than or equal to 0.40 represent a very large fraction of the post-MI population. The existence of an easy, low cost test that can be performed in a doctor's office and determines which patients may benefit from defibrillator therapy represents a significant step forward in patient management. The publication reports that 74% of the patients studied had a negative MTWA test as might be expected in this population of post-MI patients who are at overall lower risk due to their preserved ejection fraction. Nine percent of the patients were indeterminate with some patient condition interfering with the measurement. However 17% of these patients were positive and therefore likely to benefit from therapy such as an implantable defibrillator.

"Recent studies have shown that an "abnormal" MTWA test (i.e. both positive and indeterminate results) is a useful marker for the identification of high-risk patients, and a negative or normal MTWA test is a marker of low risk. These studies assessed the value of MTWA in post-MI patients with a reduced LVEF" said Takanori Ikeda, MD, PhD, FACC FACC Fellow, American College of Cardiology , Professor of Medicine at Kyorin University and the study's principal investigator. "In the present study, we assessed its value in patients with preserved cardiac function (i.e., a low-risk population). Interestingly, an indeterminate test result was not associated with arrhythmic ar·rhyth·mic
adj.
Lacking rhythm or regularity of rhythm.
 events and "a positive MTWA test" alone had a significant association. We think that a positive MTWA test could be a strong risk stratifier for sudden cardiac death in the setting of acute MI and LVEF greater than or equal 0.40. At present, EP testing has been proposed to be a tool in identifying patients who would benefit from implantation of an ICD ICD International Classification of Diseases (of the World Health Organization); intrauterine contraceptive device.

ICD
abbr.
. However, EP testing is invasive, done in a hospital setting, and expensive. So, we would like to recommend noninvasive MTWA to detect high-risk patients, particularly in patients with preserved cardiac function."

The study was a large collaborative cohort study enrolling 1,041 post-MI patients at eight medical centers in Japan. All patients had an LVEF greater than or equal 0.40 and the average LVEF was 0.55. Microvolt TWA testing was performed 48 to 66 days after acute MI, and 10 other risk variables were also evaluated.

The JACC JACC Journal of the American College of Cardiology
JACC Java Authorization Contract for Containers
JACC Joint Automatic Control Conference
JACC Journal Access Core Collection
JACC Joint Ambulatory Care Clinic
JACC joint airspace control center
 article stated that "The end points were prospectively defined as sudden cardiac death or life-threatening arrhythmic events. During a follow-up of 32 +/- 14 months, 38 patients (3.7%) died of nonarrhythmic causes and were not considered for analysis. Of the 1,003 evaluable patients, 18 (1.8%) reached an end point. Microvolt TWA was positive in 169 patients (17%), negative in 747 (74%), and indeterminate in 87 (9%). A positive microvolt TWA test, nonsustained ventricular tachycardia, and ventricular late potentials were predictors of events, and percutaneous coronary intervention Percutaneous coronary intervention (PCI), commonly known as coronary angioplasty or simply angioplasty, is a therapeutic procedure to treat the stenotic (narrowed) coronary arteries of the heart found in coronary heart disease.  decreased the risk rate. On multivariate analysis, a positive microvolt TWA test was the most significant predictor, with a hazard ratio of 19.7 (p < 0.0001). This marker had the highest sensitivity and negative predictive value The negative predictive value is the proportion of patients with negative test results who are correctly diagnosed. Worked example
Relationships among terms:

Condition
(as determined by "Gold standard")

True False
 for events."

"This is a significant study for Spectral Analytic Microvolt T-Wave Alternans[TM] as it points to the value of MTWA as a sudden cardiac death risk stratifier across the full spectrum of patients who have had an MI" said Jeffrey Langan, President and CEO (1) (Chief Executive Officer) The highest individual in command of an organization. Typically the president of the company, the CEO reports to the Chairman of the Board.  of Cambridge Heart, Inc. "Our customer base routinely uses MTWA to determine if borderline and questionable patients with an LVEF en 0.35 should receive an ICD or not. They also use it to demonstrate to those patients who are resistant to receiving an ICD that they do or do not need one. Now, as many of them have already begun to find out, it is useful in those patients with an LVEF greater than or equal 0 .40 in determining what therapeutic actions to take."

About Cambridge Heart

Cambridge Heart (www.cambridgeheart.com) is engaged in the development and commercialization of products for the non-invasive diagnosis of cardiac disease, particularly the identification of those at risk of sudden cardiac arrest. The Company's products incorporate its proprietary Microvolt T-Wave Alternans measurement technologies, coupled with its patented Spectral Analytic Method and ultra-sensitive disposable electrodes. Only Spectral Analytic Method MTWA tests are reimbursed by Medicare under its National Coverage Policy that covers patients with a wide variety of cardiac symptoms. Other major insurers in the USA also have coverage policies for the test. The T-Wave Alternans test is included in the Guideline for Management of Patients with Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death jointly developed by the American College of Cardiology (ACC See adaptive cruise control. ), The American Heart Association American Heart Association (AHA),
n.pr a national voluntary health agency that has the goal of increasing public and medical awareness of cardiovascular diseases and stroke, and thereby reducing the number of associated deaths and disabilities.
 (AHA) and the European Society of Cardiology The European Society of Cardiology (ESC) represents more than 50,000 cardiology professionals across Europe and the Mediterranean. Its mission is to reduce the impact of cardiovascular disease in Europe.  (ESC). The Company, founded in 1990, is based in Bedford, Massachusetts and is traded on the OTCBB OTCBB

See OTC Bulletin Board (OTCBB).
 under the symbol CAMH CAMH Centre for Addiction and Mental Health
CAMH Contemporary Arts Museum Houston (Houston, TX)
CAMH Comprehensive Accreditation Manual for Hospitals
.

About the Cambridge Heart Microvolt T-Wave Alternans Test

The Cambridge Heart Microvolt T-Wave Alternans Test measures extremely subtle beat-to-beat fluctuations in a person's heartbeat called T-wave alternans. These tiny heartbeat variations - measured at one millionth of a volt - are detected in any clinical setting where titration of the heart rate is possible. The preparation for the test consists of placing proprietary sensors on a patient's chest. Extensive clinical research has shown those patients with symptoms of, or who are at risk of, life threatening arrhythmias that test positive for T-wave alternans are at significant risk for subsequent sudden cardiac events including sudden death, while those who test negative are at minimal risk.

Statements contained in this press release about anticipated revenue growth, and all other statements that are not purely historical, are forward-looking statements for purposes of the safe harbor provisions under The Private Securities Litigation Reform Act The Private Securities Litigation Reform Act of 1995 (PSLRA) implemented several significant substantive changes affecting certain cases brought under the federal securities laws, including changes related to pleading, discovery, liability, class representation and awards fees and  of 1995. In some cases, we use words such as "believes", "expects", "anticipates", "plans", "estimates", "could" and similar expressions that convey uncertainty of future events or outcomes to identify these forward-looking statements. Actual results may differ materially from those indicated by these forward-looking statements. Factors that may cause or contribute to such differences include customer delays in making final buying decisions, decreased demand for our products, failure to obtain funding necessary to develop or enhance our technology, adverse results in future clinical studies of our technology, failure to obtain or maintain patent protection for our technology, failure to obtain or maintain adequate levels of third-party reimbursement for use of our products and other factors identified in our most recent Annual Report on Form 10-K under "Factors Which May Affect Future Results", which is on file with the SEC. In addition, any forward-looking statements represent our estimates only as of today and should not be relied upon as representing our estimates as of any subsequent date. While we may elect to update forward-looking statements at some point in the future, we specifically disclaim any obligation to do so, even if our estimates change.
COPYRIGHT 2006 Business Wire
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2006, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

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Publication:Business Wire
Article Type:Clinical report
Date:Dec 4, 2006
Words:1333
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