It would seem obvious that examining the health of the approximate 50,000 miles of arteries in the body would provide key information on vascular and overall aging. As Thomas Sydenham, MD said in the 1600’s in England, “a man is as old as his arteries”. This, of course, is true for women too.
Evaluating the health of the vascular system is not a common part of clinical examinations of patients and may be limited to checking a blood pressure and assessing the appearance and circulation in the hands and feet. Actually, there are a wide range of options for accurate vascular health assessments to consider. We use all of these and more at the Kahn Center for Cardiac Longevity.
Techniques at the Kahn Center
Direct Artery Imaging
There are two widely available methods of assessing arteries and determining a measure of arterial age.
A. Coronary artery calcium score (CACS) by CT. This non-invasive examination is performed without contrast or IV injection. It takes under a minute, is painless, is not claustrophobic, and has a radiation exposure similar to a mammogram. In many cities it costs $100 or less. The CACS ranges from the ideal zero to over 1,000. An online calculator (astrocharm.org) uses the CACS and several other clinical markers to predict the 10-year risk of heart attack and stroke.
B. Carotid intimal-medial thickness (CIMT). This is an ultrasound examination of the carotid arteries. The images are analyzed with digital software and the thickness of the inner 2 layers of the carotids are measured in mm. A health measure is around 0.6mm and increased CIMT is a marker of atherosclerosis. There are databases of normal CIMT by age and gender. Our clinic report included the arterial age measured. The CIMT can be measured annually to track the reversal of athersclerosis.
Endothelial Testing (the inner lining of arteries)
A. Direct measures of endothelial function can be performed using devices like the EndoPAT device available at specialty vascular clinics.
B. Indirect measures of endothelial testing include lab assessments of the urinary microalbumin/creatinine ratio and blood measurements of ADMA, myeloperoxidase, and homocysteine. Although these tests are not commonly performed in most practices, they are available from major lab companies.
C. Ambulatory 24 hour blood pressure cuff: Measuring blood pressure by an automated device over the course of 24 hours provides helpful input on the patterns of blood pressure while awake and during sleep that can reflect healthy or abnormal artery health.
Nitric Oxide Testing (the key molecule made by arteries)
A. Salivary nitric oxide can be estimated by inexpensive test strips.
B. Blood testing for assymetric dimethyl arginine (ADMA)