Over half of those who succumb annually to coronary artery disease (CAD) in the US die a sudden cardiac death (SCD) before they are ever diagnosed or treated. The two main causes of these deaths are fatal arrhythmias borne by left ventricular systolic dysfunction (LVSD) associated with viable (hibernating) myocardium, and acute infarctions of silent ischemia. The common denominators of these diagnostic entities are that they are asymptomatic in their pre-clinical phase, and that they have the same therapeutic solution, which is revascularization in a timely manner. In this article we describe: a new ambulatory impedance apparatus, the Non-Invasive Cardiac System ├óÔé¼ÔÇ£ Cardiac Surveyor (NICaS CS), to be used by the family doctor in the community to diagnose these cardiac conditions while still asymptomatic, at a very low cost; the first two case reports that led to the new discovery; and the diagnostic results of a series of tests performed with the NICaS CS on 518 people in a private clinic (at the cost of $50 each).
Coronary artery disease, sudden cardiac death, left ventricular systolic dysfunction, ambulatory impedance apparatus, Non-Invasive Cardiac System ├óÔé¼ÔÇ£ Cardiac Surveyor (NICaS CS)
Disclosure: Daniel A Goor, MD, is a shareholder in NI Medical. Samuel Sclarovsky, MD, has no conflicts of interest to declare.
Received: February 2, 2010 Accepted: February 24, 2010 Citation: US Cardiology, 2010;7(1):57├óÔé¼ÔÇ£60
Correspondence: Daniel A Goor, MD, 47 King David boulevard, Tel Aviv, Israel. E:firstname.lastname@example.org
According to Myerburg and Costellanos, the introduction of cardiac revascularization to medicine (coronary artery bypass grafting [CABG]) almost 50 years ago led to a decline in the age-adjusted mortality from coronary artery disease (CAD),1 but brought no change to the fraction of coronary deaths that are sudden and unexpected.1 Of the 650,000 who die annually in the US of CAD, 300,000├óÔé¼ÔÇ£350,000 succumb to sudden cardiac death (SCD),1,2 and another 57,000 to end-stage systolic congestive heart failure (CHF).3 This prognostic picture has not changed since the era before the introduction of revascularization by CABG operations in the late 1960s. With the new technology described here, the responsibility for timely diagnosis of asymptomatic CAD can be transferred from costly medical institutions to primary care physicians (PCPs) in the community. This alternative strategy of cost-effective early diagnosis will facilitate at long last the completion of the revolution of revascularization that began half a century ago.
Three consecutive models of the current technology were developed, the first being the Non-Invasive Cardiac System (NICaS). This was an impedance cardiographic (ICG) monitor for non-invasive measurement of the cardiac output (CO) and its derivatives.4
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