Doctor’s are flying blind

Doctors are not measuring whether their treatment is actually directly improving cardiovascular health…

Doctors aren’t routinely monitoring the direct vascular effects of your risk factor treatment – whether that be medication to treat your diabetes, cholesterol or blood pressure or asking you to engage in health lifestyle changes such as diet, exercise, weight loss, smoking cessation or stress reduction

Why?

Because we don’t have a quick, simple, noninvasive, non-operator dependent test to track changes in your blood vessel health. Currently doctors must perform an invasive, costly, risky procedure (called an acetylcholine challenge) in a cardiac catheterization lab to measure the stiffness of your arteries. This is not a practical test to routinely perform on patients at risk for heart disease.

As a heart surgeon, I am frustrated by operating on people who have a disease that is 80% preventable.

What is the Endothelium?

There are 60,000 miles of blood vessels in the human body.  Sewn end-to-end, they would wrap around the world — twice.  Every millimeter of every mile of those blood vessel is lined with a single layer of cells known as the endothelial lining or simply, the endothelium.  The total surface area of the endothelium is 4,000-7,000 m2. To put this into perspective, the surface area of a standard, professional-sized tennis court is 261 m2. Thus, having a window into the health of one’s endothelium is a powerful tool to assess vascular health.

History

The study of endothelial function and its role in cardiovascular (CV) disease has a rich history in the CV medical literature.  In the past 30 years, there have been > 170,000 studies published on endothelial function in both human and animal models.  In 2009 alone, more than 10,000 such papers were published.  This body of work includes the awarding of a Nobel Prize in medicine in 1998 to Furchgott, Ignarro, and Murad for the discovery of nitric oxide (NO) within the endothelium and its critical role in the health and function of the  endothelial layer.

…the discovery of nitric oxide and its function is one of the most important in the history of cardiovascular medicine.

Endothelial Function

The endothelium is a very complex and dynamic structure that does not simply serve as a lining for blood vessels, although that is one of its primary functions.  As a lining, it is the first line of defense for a blood vessel against cardiovascular disease.  This lining allows for a non-thrombogenic (non-clotting) interface between the vessel wall and the blood cells that are streaming by, so that blood flows smoothly inside a blood vessel and does not clot.

The endothelium also acts as a semipermeable membrane that allows the exchange of molecules from the bloodstream into the blood vessel wall. In addition to allowing molecular transport, the endothelium also synthesizes and releases its own molecules that play a key role in the defense against atherosclerosis by regulating vascular tone, cell adhesion, thromboresistance, smooth muscle cell proliferation and vessel wall inflammation. 

Most importantly, the endothelium is responsible for maintaining vascular tone by balancing the ability of a blood vessel to dilate or constrict in response to chemical / hormonal / environmental signals that affect how much blood flows within a vessel. It is this aspect of endothelial function that the SmartCuff device is built upon.

Endothelial Dysfunction

Endothelial Dysfunction is a term used to describe any abnormal function of the endothelium.  It most commonly occurs due to an impaired bioavailability of Nitric Oxide and oxidative stress. It also occurs in response to increases in shear stress, pressure, and pulsatility.  Endothelial Dysfunction can be identified in children as young as 8 years of age which is why the SmartCuff was developed with a pediatric cuff for future use in children who are at early risk for cardiovascular disease.

Endothelial Dysfunction is an early functional marker for the development of atherosclerotic disease as it precedes morphologic changes in the vasculature.  Endothelial Dysfunction is a direct result of inflammation in the wall of the artery. This inflammation is the earliest stage in the development of atherosclerosis or plaque.  When the tunica intima (the inner most layer of the 3 layers of the wall of an artery composed of endothelial cells) becomes inflamed, it becomes damaged and more permeable allowing LDL (bad cholesterol) to penetrate the artery wall and become oxidized.  When LDL is oxidized, it causes deeper damage to the artery wall and this leads to plaque buildup that results in a narrowing or closure of a coronary artery. This narrowing/closure of a coronary artery causes a heart attack and possibly death.

This is why more than 75% of all patients with a cardiovascular event (heart attack, acute coronary syndrome) have a NORMAL lipid profile (cholesterol, HDL, LDL) and blood pressure.  Even if a patient’s cholesterol is normal, if they still have inflammation in the artery wall, they can develop plaque and have an acute coronary event. 

Conditions

All risk factors for heart disease have only one thing in common – they all cause Endothelial Dysfunction. Endothelial Dysfunction is, therefore, an integrated index of both the overall cardiovascular risk factor burden and the sum of all vascular protective factors in a given patient.  Endothelial Dysfunction can be considered as a “barometer of the all risk” or the “risk of the risk factors”.

© Copyright - Cordex Systems - This device is not yet FDA approved.