Atrial fibrillation (AF) is a common type of supraventricular arrhythmia, and is especially prevalent in persons >65 years. AF is a progressive disease, characterized by chaotic electrical activation of the atria, 1 and is generally associated with an irregularly irregular ventricular rhythm and absence of distinct P waves. By accepted convention, an episode lasting at least 30 s is diagnostic. Symptoms may be absent or associated with the electrical abnormality. When present, their spectrum is known to be broad and nonspecific. The severity and extent of symptoms are affected by the patient's underlying cardiac condition, age, presence of diabetes, as well as the rapidity and regularity of the ventricular response. Many AF patients have both symptomatic and asymptomatic ("silent") episodes. AF can be classified according to its duration and the length of episodes when manifest. One not uncommon variant is indicated as occult (OAF), also called silent AF, which is asymptomatic. Being undiagnosed, it prevents timely detection and treatment. Consequently, OAF may cause stroke before the rhythm disturbance is diagnosed. 2 Characteristics of disturbed electrical phenomena in the heart are strongly associated with altered mechanical properties of the tissues involved, especially (long term) volume changes. 3 Therefore, it is not surprising that electrophysiological parameters are often studied in conjunction with imaging modalities, including echocardiography. 4 Several combined features will here be explored for selected variants of AF.