The cardiovascular system is a fluid dynamic system, governed by the laws of physics. Scientific research on such fluid dynamics can be very important in understanding the underlying physical mechanisms behind certain cardiovascular pathologies. One cardiovascular disorder currently under study is atrial fibrillation (AF).

What is Atrial Fibrillation?

Atrial fibrillation  is the most widespread cardiac arrhythmia. Globally, an estimated 30 million people suffered from atrial fibrillation in 2010, and almost 7 million of which were from USA and Europe. This disorder is characterized by an accelerated and irregular heartbeat.

AF produces a number of symptoms such as anxiety, palpitations, shortness of breath, reduced ability to exercise and fatigue. When AF is persistent, the probability of heart failure and a stroke increases.

What is the Clinical Significance of Atrial Fibrillation?

AF significantly affects the cardiovascular system, which is a fluid dynamic system. Hence, AF is of interest from both the clinical and physical point of view, especially in understanding how AF modifies the fluid dynamics of heart valves.

During the last years, the scientific community has been studying the fluid dynamic aspects of this phenomenon, linking the knowledge of doctors (which are related to symptoms and causes) with the capacity of engineers to relate causes and symptoms by means of fluid dynamic explanations. In order to do this, theoretical and numerical methods were used to investigate AF, applying the laws of physics and computational fluid dynamics.

What is important here is that fluid dynamic methods can study an isolated single phenomenon, isolating it from additional problems (hypertension, atrial dilatation, etc.) that generally affect patients. Therefore, engineers can study the effects of AF alone on heart valve dynamics. This is rarely accomplished in clinical practice because other pathologies may affect the medical framework.

Fluid Dynamics Consequences of Atrial Fibrillation

The main changes on the fluid dynamics of the heart valve during AF are determined by the temporal interval over which the backward flow occurs. The backward flow is the flow rate of blood entering into the valve. The backward volume of blood passing through the valve during a beat is the regurgitant volume, which has been found the parameter that can better indicate the performance variations of the cardiac flow rate. AF makes the performance of the pulmonary and aortic flow rate less efficient; this means that the amount of energy converted to work by the heart during blood pumping decreases.

Therefore, a correct understanding of AF can be very useful both to save lives and money, considering the significant number of people affected by this disorder. The only strategy to achieve this potentially feasible goal is to enhance the cooperation between medicine and fluid dynamics experts.