The DermaVasc™ concept
“The diagnosis and treatment of PAD in its asymptomatic stage may prove highly beneficial, particularly with respect to interventions aimed at ameliorating risk factors common to atherosclerotic disease of various vascular beds.” (1)
RISK FACTORS
Modifiable risk factors for PAD are not different from patients with coronary artery disease. (2) Major risk factors include:
smoking,
hyperlipidemia,
hypertension,
diabetes, and
the metabolic syndrome.
PAD is also more prevalent in males and in the elderly.
Dermaflow non-invasive technology (DF) has been validated in the measurement of peripheral blood flow in a variety of clinical applications, including peripheral artery disease (PAD). More recently, the technology has been combined with Transcutaneous Electrical Neural Stimulation (TENS), which is recognised as stimulating capillary blood flow. Recent pilot clinical work has confirmed earlier trials in demonstrating the ability of the technology to differentiate between PAD-affected and healthy lower limbs.
In this trial, lower limb peripheral blood flow was stimulated using Transcutaneous Electrical Neural Stimulation (TENS), which is a known effect of this technology. (3,4)
Peripheral perfusion was measured by DermaFlow technology
The effects of increasing TENS intensities on peripheral blood circulation for a healthy subject as compared to a PAD-diagnosed patient is clearly demonstrated
The test was repeated on a PAD patient, with the disease identified in one leg, with the other disease free
Although at a proof of concept stage, the consistent and significant differences between healthy and disease limbs are evident. (5)
Potential clinical applications of the DermoVasc concept in lower limb circulatory impairment include:
(1) PAD screening for patients at risk
Among healthy U.S. men aged 40 to 75 years without a history of CVD, the risk for PAD over 25 years in the absence of 4 conventional cardiovascular risk factors (current smoking, high blood pressure, high cholesterol levels, or type 2 diabetes) is rare (9 cases per 100,000 men per year). These 4 risk factors account for 75% of all cases of PAD, and at least 1 of these risk factors is present at the time of PAD diagnosis in 96% of men.(6)
The role of the GP is particularly important in the prevention and early recognition of PAD. The complex approach of our method enables the practitioner to identify at-risk patients who belong to the murky zone. These patients would remain invisible to doctors using instrumental measurements only, and require further examinations from a differential diagnostic perspective. On the long run, launching a complex screening program at GP level makes PAD patients easier to diagnose, which would lead to an earlier start of treatment, significantly improving both the patients’ quality of life and life expectancy.(7)
The DermaVasc concept will allow simple non-invasive screening of asymptomatic individuals.
“Identification of impaired microvascular blood flow and vasoreactivity by noninvasive means can lead to early identification of patients at risk for peripheral vascular and coronary artery disease. Furthermore, it can provide a quantitative assessment of the effects of a given treatment.” (8,9)
There is also rational for screening coronary artery disease patients:
Over 26% of patients with CAD present with unknown PAD, as diagnosed using ABI measurement. More than half of these patients are asymptomatic (10)
(2) PAD diagnosis of symptomatic patients.
Microcirculatory abnormalities in peripheral artery disease patients has been recognized since the 1980s (11) and confirmed in many studies since. (12)
The DermaVasc concept is well suited to detect changes in the peripheral microcirculation suggestive of peripheral artery disease.
(3) Self-monitoring of lower limb peripheral blood flow, for both asymptomatic and PAD affected patients.
The development of the DermaVasc concept will allow for home and remote self-monitoring by PAD patients with data transmission to their clinician for evaluation.
REFERENCES
(1) Criqui et al Circulation Research. 2015;116:1509–1526
(2) Nicolas W Shammas ; Vasc Health Risk Manag. 2007 Apr; 3(2): 229–234.
(3) Yamabata et al SAGE Open Medv.4; 2016PMC496251
(4) Pellinger et al www.fasebj.org/doi/abs/10.1096/fasebj.31.1_supplement.1015.35
(5) IJaffe; Data on File
(6) Joosten MM: . JAMA. 2012;308(16):1660–1667
(7) Zsombor Tóth-Vajna et al, Screening of peripheral arterial disease in primary health care Vasc Health Risk Manag. 2019; 15: 355–363
(8) Christopher J. Abularrage, MD et al, Evaluation of the microcirculation in vascular disease
(9) JVascSurg, VOLUME 42, ISSUE 3, P574-581, SEPTEMBER 01, 2005
(10) Kownator et al Archives of Cardiovascular Diseases Volume 102, Issues 8–9, August–September 2009, Pages 625-631
(11) F.A. Matsen III et al; Surg Gynecol Obstet, 150:1980: pp. 525-528)
(12) M. Midttun et al; Eur J Vasc Endovasc Surg, 13:1997: pp. 278-28.