Project Title: 

CARDIOSENS – Multimodal non-invasive technology for quantification of vascular age and cardiac function for affordable and easy cardiovascular screening in clinical and field settings

Clinical Background:

One of the primary causes of death in the modern world is cardiovascular disease (CVD). It is crucial to detect and prevent CVD early in order to decrease cardiac-related fatalities. Vasculature and cardiac function can be used to do early cardiovascular screening. Early vascular screening using clinically accepted measurements from carotid artery such as stiffness index (β), arterial compliance (AC), pressure strain elasticity (Ep), and aortic pulse wave velocity (PWV) is virtually non- existent in clinical practice due to the requirement of operator expertise, expensive equipment, and need of imaging technology required. Echocardiography is widely used for early cardio screening utilising cardiac function, which commonly assesses Ejection fraction (EF), stroke volume (SV), and cardiac output (CO). They assess the systemic and pulmonary circulation functions. However, systemic circulation abnormalities accounts to the majority of cardiovascular mortality. Currently, echocardiography is performed only when there has been a clinical presentation, like as angina, and it also requires a costly, high-end ultrasound machine. Moreover, in India, the PNDT act severely restricts the use of ultrasound imaging devices and makes it infeasible for widespread cardiovascular screening.

Cardiac output and stroke volume offer data on the average and beat-by-beat blood flow leaving the heart, making them useful clinical indicators for identifying and treating circulatory dysfunction. Critical care doctors keep an eye on a variety of variables in critically ill hypovolemic patients. It is becoming increasingly common to measure ventricular pump function and organ perfusion using stroke volume as a hemodynamic variable instead of other frequently used metrics because it is less impacted by compensatory mechanisms. The left ventricular ejection fraction (LVEF) is determined by dividing the stroke volume by the end-diastolic volume (EDV) and is an important factor in determining both systolic and diastolic heart failure. LVEF is the most commonly used clinical measure of left ventricular systolic function and is a robust predictor of death in individuals with poor LVEF heart failure. Common carotid arterial stiffness and PWV has been proven to be an independent predictor of CVD mortality and morbidity in a variety of diseases like, diabetes and stroke etc., and it is recommended to use in the treatment of hypertension. Internal jugular veins are the principal neck veins that convey blood from the head to the heart through the superior vena cava (IJV). Because the superior vena cava runs from the right atria to the internal jugular vein, pressure in the jugular veins acts as an approximate indication of central venous pressure. This research work involves assessing both vascular and cardiac function by combining both Jugular vein and common carotid artery measurements. Carotid artery is the window to the left ventricular function and jugular vein which originates from the right atria is the window to the right atria function. So, by combining both jugular vein and carotid artery as the window to estimate the systemic circulation function of the heart.

Motivation:

There is an unmet need for an easy to use, portable and field deployable image free technology that can be easily be operated by a nurse / general medical practitioner, that can quantify both early vascular ageing health markers and estimate cardiac function anomalies. My research project builds on IITM’s field validated image- free ultrasound tech (ARTSENS ® - validated on 5000+ subjects, 12 locations in India and Europe, 100+ publications, 3 patents, 25+ patents pending), and aims to build a one-of-a kind non- invasive device for both vascular and cardio screening – the CARDIOSENS. The Current technology used for measuring cardiac function and vascular ageing includes echocardiography, ALOKA prosound E- tracking device and SphygmoCor XCEL device.

The thermo-dilution approach is the clinical gold standard for CO measurement, though it is known to be a very intrusive treatment with low accuracy and may cause cardiovascular risk . Although non-invasive methods like echocardiography and electrical velocimetry are alternatives, their accuracy is frequently insufficient for clinical use currently. The gold standard for measuring ventricular volume is cardiac MRI which is expensive. LVEF can be determined using cardiac ventriculography using invasive catheterization and the MUGA scan which is also non- invasive method but has a potential concern since this method is exposed to small amount of radiation. The gold standard for measuring Jugular vein pressure (JVP) is invasive catheterization but it potentially leads to severe complications which includes thrombosis, bloodstream infection. So, there is a need for technology for accurate quantification of vascular age and cardiac markers which is simple to use for various applications.