Science is constantly growing through time. The only way to test our knowledge is what we do with what we know. In this regard TensioMed team has always been looking for the new approaches to make the most out of Arterigraph, parallel with ongoing worldwide issues such as detecting subjects having higher risk to get infected by COVID-19.
Different academically and clinically valuable information will not only renew the knowledge but also shed a light on the various practical aspects of Arteriograph to get the best possible prognostic, diagnostic and therapeutic results.
Arterial pulse pressure increases by reduction in the compliance, with lowering the diastolic blood pressure and increasing the systolic blood pressure. Having the conception of vascular wall stiffness pathophysiology, brings our attention towards a validated method and technology to quantify the vascular stiffness. PWV as a main hemodynamic predictor factor would play an important role. Arterial stiffness and pulse pressure can accelerate atherosclerosis.
Arterial stiffness can be a strong risk factor for a wide spectrum of cardiovascular pathologies, including arterial hypertension, heart failure, MI and stroke. Moreover, it appears to precede the onset of overt end-organ disease. There are several conditions link to the arterial stiffness such as aging, by reducing the elastic properties of the vascular wall and development of chronic or low-grade inflammation. Metabolic disease, such as diabetes mellitus (especially DM2) which the accelerated arterial stiffening is one of its major complications. Childhood obesity could become advanced in adulthood has a great prevalence for immediate cardiovascular damage and arterial stiffness. Vitamin D deficiency and hyperparathyroidism can be another indicator of arterial stiffness.
Sleep quality and duration have a great impact on arterial stiffness which cause the unfavourable cardiovascular outcomes. Smoking may differentially affect specific arterial segments stiffness and would need more regional study.
Beyond blood pressure control, it may be crucial to therapeutically address the intrinsic biomechanical properties of the arterial wall and its measurement. Moreover, further pathological outcomes and comorbidities can be prevented.
Stiffness of the elastic arteries arises the higher pulse pressure (PP) and increased pulse wave velocity (PWV), which is an unconventional indicator of cardiovascular risk, due to arterial aging. Following up the aging, there are several other determinants such as genetics and environmental factors in progression of the arterial stiffness. The presence of dyslipidaemia, tobacco smoking, diabetes, high heart rate (HR), etc. is often associated with increased stiffness, but the effect of these risk factors is erratic in the development of arterial stiffness.
Over six years of study on treated hypertensive in comparison to normotensive subjects, shows the PWV progression and increase in arterial stiffness over a period. In treated hypertensive patients for accelerated progression in PWV, three factors are identified: “uncontrolled blood pressure values, increased HR, and increased serum creatinine.” In contrast, between the aortic stiffness and other main cardiovascular risk factors there is no association.
Early detection and accurate measurement of PWV in daily clinical routine for high risk individuals can play a major role in lowering the speed of progression and further unsatisfactory outcomes.
Arterial stiffness occurs as a result of senescence and arteriosclerosis. Collagen degradation and elastin production are the two major determinant factors of arterial stiffness in vascular smooth muscle tone and transmural distending pressure. Arterial pressure, flow dynamics, and coronary perfusion by decreasing in the compliance of the central vasculature can impact on the cardiac performance. We can divide the arterial system into two systems:
a) The large elastic arteries: store the ejected blood during systole and drive it to the periphery during diastole.
b) Muscular arteries: competent for changing in the tone by contracting the smooth muscle.
When the heart contracts, the resulting forward propagated wave interfaces with the intrinsic impedance of the aorta, make a relatively low velocity (pulse wave velocity; PWV) pressure wave. Differences in vascular wall characteristics and diameter cause varying impedance mismatch distally and form the reflected wave. The return timing of the reflected wave from the peripheral site which is affected by the pulsatile component of arterial afterload can be a significant factor of arterial stiffness.
Due to injury assisted by pulsatile pressure, as may predispose the intima to atherosclerosis which can lead to further Cardiovascular disease (CVD). Measuring the aortic PWV as a crucial parameter of arterial stiffness in a daily clinical routine which may remain undiagnosed due to difficulties of the old invasive method, especially in asymptomatic individuals, would be worthful to prevent further worse outcomes. By referring to this concept Arteriograph as a validated non-invasive technique can play a key role in this regard.
Although, prevention of the disease always plays an important role in public health term and being preferable to treatment, but also reducing the progression time of the disease, alleviate the relevant risk factors and choosing the proper way of following up the individual who agony, would be efficient in reaching our goal which is increasing the quality of life and increasing the fellow’s healthy lifelong.
Fatty streaks formation is the beginning of atherosclerosis and then it progresses with atheroma and atherosclerotic plaque formation. The most accelerating factors for atherosclerosis can be mentioned as malproduction and dysfunction of NO, and inflammation, Hypercholesterolemia, LDL increase, HDL decrease. For patients with risk factors, an early detection of atherosclerosis allows the confirmation of plaque presence, it’s extent estimation occlusion and penetration by flow limiting and remodeling the endothelial layer.
Choosing the non-invasive device which has the possibility of measuring the exact parameters as validated invasively, would open a new door in both clinical and research fields. It can be an occasion opportunity to precision of the disease estimation and prediction of pursuing the disorder’s outcome, as well as enhancing our inspection for an appropriate and on time treatment.
Arteriograph by measuring almost all the predictors of cardiovascular disease and stiffness such as PWV, AXI ,…which are validated invasively can increase the life expectancy of the individual and deduct the further cost for society and sufferers with simple, time saving and reliable device.
Wide variety of genetic and environmental factors are responsible for the progression of atherosclerosis, a condition that afflicts the large and medium sized arteries. It is characterised by localised fibrous thickening of arterial wall, formation of plaques which are prone to rupture, and formation of thrombi.
Therefore, the late consequences of atherosclerosis will result in life-threatening disease such as coronary heart diseases, cerebrovascular disease, and peripheral vascular disease.
Upon narrowing of coronary artery and insufficient perfusion of heart, pain-producing substances accumulate in the myocardium and cause angina pectoris which disappears in rest. If coronary artery is unable to supply the heart due to atherosclerosis, myocardial infarction happens.
In cerebral circulation, atherosclerotic plaques are the main cause of thrombotic stroke. Extensive atherosclerosis in abdominal aorta can lead to aneurismal dilation and rupture. Constriction of one or both renal arteries due to atherosclerosis will cause renovascular hypertension, and last but not the least pain, ulceration and gangrene are the results of compromised circulation in limbs.
In most developed countries atherosclerosis is the underlying cause in almost half of all deaths. However, along with improvement of lifestyle, early detection of arterial stiffness and accessibility to screening methods are crucial. Arteriograph provides an ideal solution by revealing atherosclerosis and avoiding a large portion of clinical problems.
Several events occurring simultaneously lead to development of atherosclerosis. Among them endothelial damage is the most important initiator of atherosclerosis.
High blood pressure, diabetes, smoking and high concentrations of cholesterol and triglyceride in the blood, known as “lethal four”, are the main causes of arterial damage and its further complications.
Elevated levels of low-density lipoprotein (LDL), will enhance the intima deposition of extra LDL. Later the trapped LDL undergoes further modifications and will be taken up by macrophages which then transform to foam cells. These together incorporate to formation of fatty streak and fibrotic plaque, proliferation and dedifferentiation of intima media, activation of platelets and haemostasis and consequently endothelial cell injury.
Along from healthy lifestyle including low LDL diet, physical activity and reduced amount of alcohol and tobacco smoke, regular assessment of central cardiovascular parameters plays an important role to detect pathological changes in arterial system before it leads to serious clinical events.
Arteriograph is known to be the gold standard of this early detection. Non-invasive and accurate analysis of central hemodynamics data can reveal the true vascular age and could be a great predictor of future cardiovascular complications.
Endothelium is responsible for maintaining vascular tone trough Nitric Oxide (NO). Nitric Oxide as a crucial endothelium-derived molecule for vascular relaxation proved the endothelium to be more than just a passive interface between blood and the vessel wall.
Moreover, endothelial damage in response to injuries such as high mechanical stress, hypertension, or free radicals, will lead to insufficient amount of Nitric Oxide production and increased secretion of local mediators and tissue ACE-Ang II. Later, these changes will proceed by vascular pathologies such as Atherosclerosis.
Over the past few years many methodological approaches have been developed to measure the function of the endothelium. The most common non-invasive surrogate are Flow Mediated Dilation (FMD) and Arteriography.
FMD measures the ability of the arteries to respond to endothelial NO release during reactive hyperaemia after a brief occlusion of the artery with a pressure cuff. The respective diameter changes of the artery are measured by ultrasound technique.
Although the ability of measuring endothelial function by Flow Mediated Dilation (FMD) has boosted clinical research in this field, but its application is technically challenging and requires extensive training and standardisation. Arteriograph however, is easy to access and perform, automated and have shown correlation with invasive micro vascular function. This make it a perfect candidate to be used as a clinical tool in daily practice.
Since the discovery of the obligatory role which has played by the endothelial cells in the relaxation of isolated arteries in the rabbits in response to exogenous stimuli is getting more attention, the endothelial function has been the matter of interest in several studies.
The endothelium-dependency of vascular resistance rests on a transfer of vasodilator material from the endothelial cells to the underlying vascular smooth muscle. It shortly became obvious that examination of vasoconstriction & vasodilation in human blood vessels, has a great diagnostical value and is required to be a part of routine clinical examinations.
However, the gold standard method to evaluate the endothelial function Flow Mediated Dilation (FMD) remains at the researchers’ mind.
The Arteriograph is a non-invasive validated device, which uses oscillometric pressure curves registered by pressure changes in the artery which are determined by endothelial function. Through this method one can easily gain a comprehensive set of information regarding the Total Peripheral Resistance and endothelial status.
Cough, Fever and Shortness of Breath. These are common symptoms of COVID-19 infected patients. All of them initiated in respiratory system just because of abundance expression of ACE2 as a co-receptor for virus access to the lungs. But lungs are not the only tissue producing ACE2.
The most common comorbidity observed in patient affected by COVID-19 is HYPERTENSION. Moreover Acute Kidney Injury and Diabetes Mellitus are considered as major clinical events usually observed in COVID-19 patients suggest that endothelium as the largest tissue in the body with same potential as lungs in expressing ACE2 should be the target of studies.
It has been shown that ACE2 cause vasodilatory effect, counterbalancing vasoconstricory effect of ACE1. Thus people with high ACE2 level might be prone to suffer from COVID-19 with higher probability. We suppose that elderly people with unexpected low peripheral resistance may be suspected for development of COVID-19.
Arteriograph can provide valuable information in case of endothelial integrity by measuring Augmentation index as a marker of total peripheral resistance. Based on this ability several investigations can be conducted to reveal whether endothelium is the main target of COVID-19 or not.
Atherosclerosis is a slow, complex disease that starts even in childhood and progresses when people grow older. In some subjects the disease can accelerates rapidly, causing major cardiovascular events like stroke or unexpected death. It is generally known that it begins with functional changes of endothelium such as insufficient NO production and results in structural damage to the most inner layer of the artery.
Knowing that atherosclerosis is responsible for a large portion of the clinical problems, possibly the single most influential solution would be advance detection of existing but hidden traces of premature atherosclerosis.
Arteriograph as an innovative device provides essential data required for this awareness. Parameters which are key indicators of clinically silent arterial damages consist the basis action of Arteriograph. Reliable, validated results of these measurements provide accurate, independent, and cumulative prognostic markers of future CV events.