The Ability Of The PD2i Cardiac Analyzer To Predict Risk Of Ventricular Tachyarrhythmic Events

The annual incidence of sudden cardiac death in the United States has recently been
estimated at 450,000. Most of these patients die from ventricular tachyarrhythmias.
Currently, there is a limited ability to predict reliably which patients are at risk for
these events. Implantable cardioverter defibrillators (ICDs) are highly effective at
treating the arrhythmias that cause sudden death. Multiple clinical trials demonstrating the
efficacy of ICDs for the primary prevention of sudden death have been completed, leading to
a relaxation of the selection criteria for their use, and therefore a potentially large
expansion in the pool of patients eligible for these devices. This has major economic
implications for the health care system, and has led to a need for better prospective
identification of patients who are or are not at high risk for sudden death.

The existence of beat-to-beat changes in heart rate, termed heart rate variability HRV), has
long been recognized by physiologists. However, over the past 15 years, it has been
determined that HRV is not a random phenomenon but can be influenced by the brain through
the autonomic nervous system.

Promising work in the analysis of HRV may provide a means of predicting which patients are
at risk for sudden death. HRV analysis utilizes mathematical modeling of ECG data to gain
insight into the subtle variations in heartbeat patterns which occur from beat-to-beat.

The development of a system that could better identify the patients at risk of arrhythmic
events would have a significant impact on clinical and economical fields. This study will
test software developed by Vicor Technologies that can potentially identify patients at risk
of arrhythmic events. It works as a generic digital-electrocardiogram (ECG) device, as it
would normally be used by technical personnel in the routine care of outpatients.

Inclusion Criteria:

- Age >18 years

- Left Ventricular Ejection Fraction (LVEF) <35%

- Prior myocardial infarction

- Symptomatic congestive heart failure

- Referred for EP testing and/or prophylactic ICD implantation

Exclusion Criteria:

- Currently has implanted pacemaker or ICD

- Current atrial fibrillation/flutter or atrial fibrillation/flutter requiring
cardioversion within the previous 6 months

- Cardiac surgery or percutaneous revascularization, MI, unstable angina, or CVA within
the previous 30 days

- Antiarrhythmic drug therapy other than a beta-blocker within the previous 6 months

- Previous episode of sustained VT/VF or cardiac arrest, except in the setting of acute
myocardial infarction or other reversible cause

- Life expectancy of less than one year from any non-cardiac cause

- Expected cardiac transplantation within 6 months