Cardiovascular diseases (CVDs) remain the top leading cause of death worldwide. According to the latest world health organization (WHO) statistics, 17.7 million people die annually from CVDs, approximately 31% of all deaths worldwide. WHO had forecasted that by 2030, almost 23.6 million people will die from CVDs, mainly from heart disease and stroke [1]. Coronary heart disease (CHD) deaths in Malaysia has reached 30,598 or 22.13% of total deaths, ranks Malaysia 63 in the world. In 2016, WHO and partners have launched a new initiative aiming to reduce the global threat of cardiovascular disease, including heart attack and stroke. One of the three main packages aimed by this global initiative is reduction of heart attacks and strokes can be done through equitable and cost-effective healthcare technical tools. In particular, regular checkups of blood pressure, blood cholesterol and monitor the heart electromechanical activity via standard cost-effective tools. This initiative was created due to the existing healthcare systems in low and middle-income economies which provide the clinical care only after the symptoms of an event has occurred. Eventually, for most heart disease cases, the existing approach may come up with a more complex and expensive solution because the patient has already been in a high degree of danger.

The heart is the central unit of the blood delivery (circulatory) system with function to provide the nutrition-rich blood to various organs of the body and simultaneously removing the cellular waste.  In fact, the heart beats nearly 100,000 times a day, pumping about 2000 gallons of blood. The heart beats are generated as a result of systematic electromechanical activity that occurs within the heart muscle, in which two signals are produced as a representation of the heart electromechanical activity (see Figure 1). Electrocardiogram (ECG) is a measure of the electrical activity of the heart, whereas the phonocardiogram (PCG) is used to represent the mechanical activity of the heart valves. 2. HEART & ECG Despite the new advances in cardiac imaging, the stethoscope is one of the oldest tools and still being used for primary cardiac auscultation examination. Listening to the cardiac auscultation using the traditional stethoscope is often difficult to interpret due to the capability limits of the human ear. Digital stethoscope allows clinicians in ambulatory units to visualize the heart sound (PCG) auscultation and helps to identify any suspected cardiac disorders before referring to a more advanced but less readily accessible and potentially more expensive diagnostic tools, such as ultrasound, magnetic resonance imaging (MRI), and echocardiography. Since both ECG and PCG signals are coming from the same physiological source, the heart, these signals provide complementary information about the heart health status. The ECG is a very important test to interpret the cardiac rhythm and could be used for automatic detection of the heart conduction system abnormalities. The PCG, on the other hand, provides a valuable information which is used for valvular heart disease detection.