| 释义 |
paroxysmal tachycardia
Translations
Paroxysmal Tachycardia
Paroxysmal Tachycardia a type of arrhythmia marked by attacks during which the heartbeat is accelerated while the normal order of cardiac contractions is retained. A distinction is made between supraventricular and ventricular forms of paroxysmal tachycardia. The supraventricular form generally occurs in neuroses and results in a heart rate of 180— 260 beats per minute. Ventricular paroxysmal tachycardia generally arises in heart disease and is characterized by a heart rate of 140–200 beats per minute; the condition is also accompanied by vertigo, weakness, pallor, progressive dyspnea, cyanosis, and coughing. With both forms, an attack can last from several minutes to several days or longer and can end as suddenly as it begins. Paroxysmal tachycardia is treated with antiarrhythmic agents, cardiac glycosides, Inderal, and electric cardiac pacemakers. In the supraventricular form, vagal tone is increased by special techniques, for example, by applying pressure to the eyeballs. paroxysmal tachycardia
tachycardia [tak″e-kahr´de-ah] abnormally rapid heart rate, usually taken to be over 100 beats per minute. adj., adj tachycar´diac. A, Sinus tachycardia; B, Ventricular tachycardia. From Chernecky, 2001.antidromic circus movement tachycardia a supraventricular tachycardia supported by a circuit" >reentry circuit that uses the atrioventricular node in the retrograde direction and an pathway" >accessory pathway in the anterograde direction; this produces a broad QRS rhythm indistinguishable from ventricular tachycardia. Such a tachycardia may also use two pathways" >accessory pathways (one anterograde and one retrograde) and not involve the AV node at all.atrial tachycardia a rapid heart rate, between 140 and 250 beats per minute, with the ectopic focus in the atria and with no participation by the atrioventricular node or the sinoatrial node. It is recognizable on the electrocardiogram because the P wave precedes the QRS complex, as opposed to being merged with it or following it. This condition is usually associated with block" >atrioventricular block or digitalis toxicity.benign ventricular tachycardia tachycardia originating in the ventricles, not associated with structural heart disease or significant hemodynamic symptoms.bidirectional ventricular tachycardia (bifascicular ventricular tachycardia) a ventricular arrhythmia characterized by heart rates of 90 to 160 beats per minute, alternating right and left deviation" >axis deviation, ectopic focus that alternates between the anterior superior and posterior inferior fascicles, and a right bundle branch block pattern in lead V1; seen in digitalis toxicity and other conditions.chaotic atrial tachycardia an ectopic atrial tachycardia due to multifocal activity, characterized by at least three different shapes of P waves on the electrocardiogram; often associated with chronic obstructive lung disease.circus movement tachycardia (CMT) a circuit" >reentry circuit that uses an pathway" >accessory pathway or pathways; there are two subtypes, antidromic and orthodromic circus movement tachycardia.ectopic tachycardia rapid heart action in response to impulses arising outside the sinoatrial node.junctional tachycardia rhythm at the rate of 100 to 140 beats per minute that arises in response to impulses originating in the atrioventricular junction, i.e., the atrioventricular node. It is often seen with digitalis toxicity and is due to triggered activity, but it may also be due to altered automaticity. In the case of digitalis toxicity, the term may be used to encompass the entire span of junctional rates with this condition, i.e., approximately 70 to 140 beats per minute.monomorphic ventricular tachycardia a type that has a uniform beat-to-beat QRS morphology.nonsustained ventricular tachycardia a type that terminates spontaneously within 30 seconds and does not lead to hemodynamic collapse.orthodromic circus movement tachycardia a supraventricular tachycardia supported by a circuit" >reentry circuit that uses the atrioventricular node in the anterograde direction and an pathway" >accessory pathway in the retrograde direction, producing a narrow QRS complex.orthostatic tachycardia disproportionate rapidity of the heart rate on arising from a reclining to a standing position.paroxysmal tachycardia rapid heart action that starts and stops abruptly.paroxysmal atrial tachycardia paroxysmal supraventricular tachycardia.paroxysmal supraventricular tachycardia (PSVT) a narrow QRS tachycardia that begins and ends abruptly; it may be terminated with a vagal maneuver. It has two common mechanisms, atrioventricular nodal reentry and movement" >circus movement that uses the atrioventricular node anterogradely and an pathway" >accessory pathway retrogradely. On the electrocardiogram it is characterized by abrupt onset, and mechanisms are differentiated by the relation of the P wave to the QRS complex.polymorphic ventricular tachycardia a type that has a constantly, and sometimes subtly, changing beat-to-beat QRS configuration.potentially malignant ventricular tachycardia a type that is not associated with structural heart disease or hemodynamically important cardiac symptoms but is sometimes associated with left ventricular dysfunction.sinus tachycardia (ST) a rapid rhythm originating in the sinoatrial node with a rate of usually 100 to 160 beats per minute; conduction through the ventricles is normal. During exercise or stress this is normal, but if it occurs during rest it is abnormal.supraventricular tachycardia a combination of junctional tachycardia and atrial tachycardia.sustained ventricular tachycardia tachycardia that lasts more than 30 seconds and leads to hemodynamic collapse.ventricular tachycardia an abnormally rapid ventricular rhythm with aberrant ventricular excitation, characterized by at least three consecutive complexes" >ventricular complexes of more than 100 beats per minute. It is generated within the ventricle and is most often associated with dissociation" >atrioventricular dissociation.par·ox·ys·mal tach·y·car·di·arecurrent attacks of tachycardia, usually with abrupt onset and often also abrupt termination, originating from an ectopic focus which may be atrial, AV junctional, or ventricular.par·ox·ys·mal tach·y·car·di·a (par'ok-siz'măl tak'i-kahr'dē-ă) Recurrent attacks of tachycardia, with abrupt onset and often also abrupt termination, originating from an ectopic focus that may be atrial, atrioventricular junctional, or ventricular. paroxysmal tachycardia A heart disorder featuring apparently spontaneous episodes of rapid heartbeat, in excess of 100 per minute. The condition may be caused by drugs, anaemia, HEART FAILURE, thyroid gland overactivity and conduction defects within the heart.ThesaurusSeetachycardia |