What characteristic is commonly observed in patients with atrial fibrillation?

In patients with atrial fibrillation, a hallmark characteristic is the shortened left ventricle diastolic filling time. This occurs because the chaotic and irregular rhythm associated with atrial fibrillation leads to an ineffective atrial contraction. As a result, there is less time for blood to fill the left ventricle during diastole, which can ultimately contribute to reduced stroke volume and impaired cardiac output.

The rapid and irregular ventricular response in atrial fibrillation places the heart in a state of constant variability between beats, which significantly shortens the time available for the left ventricle to fill with blood between contractions. This physiological change is important for understanding the implications of atrial fibrillation on overall heart function and the potential risks for heart failure and other complications.

While increased left atrial thickness can occur in atrial fibrillation due to chronic pressure overload or volume overload, it is not as universally acknowledged as a primary characteristic compared to the shortened diastolic filling time. Similarly, reduced heart rate variability can be observed, but it is more of a consequence of autonomic nervous system changes rather than a direct characteristic of atrial fibrillation itself. Lastly, decreased pulmonary blood flow is not typically associated with atrial fibrillation in isolation, as the