Abstract: Arterial stiffness is an independent predictor for coronary artery diseases (CAD). Various methods to predict coronary artery involvement are known but most of them have limited applicability in large-scale population screening due to cost barrier [1].

Photoplethysmography (PPG) to capture digital volume pulse signal is a simple, low-cost and noninvasive method for rapid assessment of arterial health conditions. An important application of PPG signal analysis has been towards early detection of altered arterial stiffness leading to increased risk of CAD. A Two Pulse Synthesis (TPS) model has been suggested recently for measurement of vascular parameters based on PPG signal and the usefulness of the model has been established for hypertensive and diabetic subjects [2].

This communication reports the outcome of a study based on the use of TPS model on finger-tip PPG of 40 suspected CAD subjects. The TPS model-based parameters considered in the study are Rise Time, Reflection Index, Foot-to-Foot Delay, Differential-Pulse-Spread and the Spread-Delay Ratio. Angiography has been subsequently carried out on these subjects and the findings have been compiled to find out sensitivity, specificity, positive and negative predictive values.

The study shows that the Positive Predictive Value of the TPS model is respectable (69%) while the Negative Predictive Value (93%) is high. It appears that this mathematical model may be applied to predict or rule out CAD conditions fairly successfully. Gradual development of functional embarrassments even in the absence of clinical manifestations may be possible with PPG analysis through periodic application of TPS model.