Audible and Subaudible Components of the First and Second Heart Sounds

Cardiovascular disease (CVD) has been a pressing medical issue in the United States for over a century and has been a leading cause of death [1], [2] with a great impact on mortality, morbidity, and healthcare cost. The Centers for Disease Control and Prevention (CDC) [3] reported that CVD is responsible for one death every 34 seconds and approximately 697,000 deaths in 2020 alone. Additionally, between 2017 to 2018, CVD directly and indirectly cost the United States economy approximately 378 billion dollars [2].