Simple Test Identifies Patients at High Risk of Sudden Cardiac Death

An innovative algorithm accurately identifies individuals at high risk of suffering sudden cardiac death (SCD) within a six-month period that could benefit from an implantable cardioverter defibrillator (ICD).

The Vicor point correlation dimension algorithm (PD2i) Cardiac Analyzer (CA) test is an inexpensive, noninvasive procedure that requires no active patient participation; it is not derailed by irregular or ectopic heartbeats, and can be performed on patients taking beta blockers commonly prescribed for coronary artery disease (CAD). The test is based on research that established that sudden cardiac death is caused by abnormal neurological communication between the brain and heart. By analyzing fifteen minutes of electrocardiogram (ECG) data, the PD2i CA can detect if the communication between the multiple neurologic centers that normally work in semi-coordination to control the heart rhythm are being "overly-coordinated.” Excessive coordination of these control systems, reflected by a reduced PD2i value, is a clear indication that the patient is at imminent risk of sudden cardiac death.

The PD2i nonlinear algorithm evaluates this neurological relationship by measuring the degrees of freedom of the patient's heart-rate variability within sensory-motor loops such as temperature, pH, baroreceptor reflex, and others; the degree of cooperation between those loops is reflected in the degrees of freedom of the heart rate's variability - a phenomenon caused by the brain's influence. In healthy individuals, these loops tend to work in opposition and more or less independently. However, when the loops begin to coordinate to a high degree, it is a sign (paradoxically) that the body is not doing well and that the brain is "marshalling the forces” to work together to keep the body alive. This "hyper-coordinated” condition is not sustainable and can lead to ventricular tachycardia, ventricular fibrillation, and sudden cardiac death. Knowing the degrees of freedom permits far more accurate evaluation of near-term risk of sudden cardiac death. The PD2i CA was developed by Vicor Technologies (Boca Raton, FL, USA) and has been approved by the U.S. Food and Drug Administration (FDA) to measure heart rate complexity.

"All of the clinical trials of our PD2i conducted with the U.S. Army Institute for Surgical Research (USAISR, Fort Sam Houston, TX, USA) reveal the PD2i to be the only diagnostic capable of consistently and accurately determining severity of injury and the probability of survival in critically injured soldiers and civilians utilizing both 'raw' and 'noisy' ECG data,” said David H. Fater, CEO of Vicor Technologies, commenting on the announced testing of the PD2i under the USAISR Critical Combat Care Engineering (C3E) program.

Related Links:
Vicor Technologies
U.S. Army Institute for Surgical Research