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Related to premature contraction: premature atrial contraction, ventricular extrasystoles


Premature beat of the heart.



the most common form of arrhythmia. The condition is characterized by irregular heart contractions (extra-systoles) caused by impulses from an additional focus of excitation arising in the myocardium. Since the heart muscle remains unexcitable for some time after every contraction, the next normal impulse usually cannot cause a systole. As a result, a longer than normal contraction, that is, a compensatory pause, occurs. An extrasystole is generally felt as a temporary sinking sensation, or an “interruption in the heart.” Atrial extrasystoles arise in the atria, and ventricular extrasystoles in the ventricles. Extrasystoles may be single or multiple, and they may occur chaotically or with a certain rhythm, for example, after every normal contraction (bigeminal). Sometimes several extrasystoles occur in succession.

Extrasystoles can occur in healthy persons, and, in most cases, occasional infrequent extrasystoles have little clinical significance. Atrial extrasystoles, however, may result from myocardial disease, for example, mitral insufficiency or cardiosclerosis. Frequent atrial extrasystoles in these diseases are an early sign of auricular fibrillation, especially when they occur in rapid succession. Ventricular extrasystoles may result from myocardial disease or neurological, mental, and other disorders. Successive ventricular extrasystoles originating from different places may precede a severe form of arrhythmia called ventricular fibrillation.

Electrocardiography plays an important part in diagnosing ex-trasystoles. Treatment is determined by cause. The administration of antiarrhythmic agents, for example, propranolol and potassium preparations, is sometimes required.


References in periodicals archive ?
He sewed a stitch into the cervix to prevent it from opening and gave her the drug progesterone to stop premature contractions.
A WOMAN PREGNANT WITH TWINS was admitted to the hospital because of premature contractions.
For most women it's safe to have sex for as long as you feel like it - unless there are complications such as bleeding or premature contractions.
The complications included more fevers and premature contractions and two cases of pulmonary emboli in the laparotomy group, compared with no pulmonary emboli in the laparoscopy group, reported Dr.
In general, obstetricians were more likely to select more aggressive therapy for women with premature contractions without changes in cervix.
These guidelines show that women with epilepsy are not at a substantially increased risk of having a cesarean section, late-pregnancy bleeding, or premature contractions or premature labor and delivery.
A negative test is highly reassuring in a patient who presents to your labor and delivery triage center with regular premature contractions, a long and closed cervix, a healthy fetus, and no other complications, Dr.
Some of the exclusions could be related to both premature contractions and low birthweight and could therefore bias the study's results, but none of the subjects excluded for those reasons in this study experienced preterm contractions or preterm labor.