Atrial flutter

Description:

The atrial flutter is a considerable increase of reductions of auricles (to 200-400 in a minute) at preservation of the correct regular atrial rhythm.

Due to the big frequency of atrial impulses it usually is followed by incomplete atrioventricular blockade that provides more rare rhythm of ventricles.

In most cases the atrial flutter proceeds in the form of paroxysms duration from several seconds to several days as, being an unstable rhythm, rather quickly under the influence of treatment passes or into a sinoatrial rate, or (more often) into a ciliary arrhythmia. Both of these disturbances of a rhythm are generally noted at the same patients, replacing each other. The constant form of an atrial flutter which sometimes call also "steady" meets very seldom. The standard temporary criterion of differentiation of paroxysmal and constant forms of an atrial flutter does not exist.

Due to the instability of an atrial flutter prevalence it is not established. It is found in 0,4-1,2% of inpatients, and in men approximately by 4,5 times more often than at women. Frequency of emergence of an atrial flutter, as well as ciliary arrhythmia, increases with age.

Atrial flutter reasons:

As a rule, the atrial flutter is connected with organic heart diseases. It especially often develops within 1 week after cardiac operations, is more rare - after aortocoronary shunting. As the reasons of this arrhythmia serve also defects of the mitral valve of a rheumatic etiology, the ischemic heart diseases various forms, is preferential in the presence of heart failure, a cardiomyopathy and chronic obstructive diseases of lungs. The atrial flutter practically does not occur at healthy faces.

Atrial flutter symptoms:

Clinical manifestations of an atrial flutter depend mainly on ChSS, and also the nature of an organic heart disease. At carrying out coefficient 2:1-4:1 atrial flutters are transferred in general better, than blinking, thanks to the arranged rhythm of ventricles. "Insidiousness" of trembling consists in a possibility of unpredictable sharp and significant increase in ChSS owing to change of coefficient of carrying out at the minimum exercise and emotional stress and even upon transition to vertical position that is not peculiar to a ciliary arrhythmia. It often is followed by heartbeat and emergence or aggravation of symptoms of venous stagnation in lungs, and also arterial hypotension and dizziness, up to a loss of consciousness. At clinical inspection arterial pulse is more often rhythmical and speeded up. Neither that, nor another, however, is obligatory. At the carrying out coefficient equal 4:1, ChSS can be in limits 75-85 in 1 min. When the size of this coefficient constantly changes, a heart rhythm wrong as at a ciliary arrhythmia, and can be followed by deficit of pulse. The frequent and rhythmical pulsation of cervical veins is very characteristic. Its frequency corresponds to an atrial rhythm both usually twice and more exceeds the frequency of arterial pulse.

Diagnosis:

Diagnosis is based on data of an ECG in 12 assignments.

The most characteristic electrocardiographic signs of an atrial flutter are:

existence on an ECG frequent - to 200-400 in a minute - atrial waves of F regular, similar at each other having the characteristic sawtooth form (assignments of II, III, aVF, V1, V2);

in most cases the correct, regular ventricular rhythm with identical - R-R intervals (Behind an exception of cases of change of degree of an atrioventricular block at the time of registration of an ECG);

existence of the normal not changed ventricular complexes, precedes each of which defined (more often constant) quantity of atrial waves of F (2:1, 3:1, 4:1 etc.).

Current and complications:

The atrial flutter at most of patients proceeds in the form of separate, rather short, episodes which often arise against the background of their blinking which is steadier rhythm. Therefore to judge an atrial flutter role in emergence of complications at such patients very difficult. There are instructions on the fact that system thromboembolisms meet extremely seldom, thanks to preservation of mechanical function of auricles and smaller, than at a ciliary arrhythmia, frequency of their rhythm. At considerable ChSS against the background of a heavy organic heart disease the atrial flutter, as well as blinking, can lead to development of acute left ventricular and chronic heart failure.

Treatment of an atrial flutter:

Treatment and secondary prevention of an atrial flutter are carried out in general as well as at their blinking. At the same time it should be noted considerably big resistance of an atrial flutter to medicamentous therapy both when stopping paroxysms, and at their prevention that creates sometimes big problems. Considerable difficulties can arise also at pharmacological control of frequency of a ventricular rhythm. At the same time, in connection with instability of atrioventricular carrying out when trembling dserdiya, its a little long preservation is undesirable, and it is necessary to make every effort for the fastest recovery of a sinoatrial rate or transfer of trembling in blinking.

For stopping of paroxysms of an atrial flutter use medicamentous therapy, electric cardioversion and frequent atrial EX-.

As well as at a ciliary arrhythmia, for recovery of a sinoatrial rate use the antiarrhytmic drugs IA, 1S and III of classes which appoint intravenously or inside. The last two groups of drugs are more effective and less toxic, than the first. It should be noted especially that rather new drug ибутилид at intravenous administration allows to recover a sinoatrial rate approximately at 70% of patients.

It is necessary to emphasize that in order to avoid sharp increase in ChSS as a result of improvement of atrioventricular carrying out, up to 1:1, the attempt of medicamentous cardioversion by the drugs IA and 1C of classes can be carried out only after blocking of an atrioventricular node by means of digoxin, verapamil, diltiazem or ß adrenoblockers.

Choice drug for medicamentous control of frequency of a ventricular rhythm at an atrial flutter is verapamil. Less permanent effect is provided by ß adrenoblockers and digoxin. In view of resistance of trembling to digoxin rather high doses of drug often are required. In general control of ChSS by means of the medicamentous drugs which are slowing down atrioventricular conductivity at this disturbance of a rhythm is much less reliable, than at a ciliary arrhythmia. At its inefficiency with success use non-drug methods - catheter ablation and modification of an atrioventricular node.