Estimates of the coexistence of epilepsy and psychogenic nonepileptic seizures vary from 5 percent to more than 60 percent, depending on the study setting and diagnostic criteria.3 Recent studies17, 22 using strict criteria for a diagnosis of epilepsy found that only 5 to 10 percent of patients with non-epileptic seizures have concurrent epileptic seizures.
the contraction, or period of contraction, of the heart, especially of the ventricles, during which blood is forced into the aorta and pulmonary artery. atrial systole. contraction of the atria by which blood is forced into the ventricles; it precedes the true or ventricular systole. extra systole. see extrasystole.
Their purpose is to allow blood to move forwards through the heart and to prevent it flowing backwards into the previous chamber. How does the heart work? The heart muscle contracts in two stages to squeeze blood out of the heart. This is known as systole. In the first stage, the upper chambers (atria) contract at the same time, pushing blood down into the lower chambers (ventricles).