Forecourt flares

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Forecourt flares is the most frequent important heartbeat disturbance, however in Germany from it about humans suffer one million. In contrast to ventricular fibrillations is not directly life-threatening forecourt flares, leads however with approximately 85 per cent of the concerning to symptoms such as heart lawns, unrest feeling or achievement weakness. Beyond that forecourt flares with many patients a increased impact accumulation risk means. Nowadays most patients a medicamentous or invasive treatment can be offered, the one normal or nearly normal way of life made possible.

Organization

Forecourt flares becomes after an internationally recognized data standard of the American Heart Association (AHA) and the American college OF Cardiology (ACC) in

1. for the first time discovered forecourt flares,
2. paroxysmales forecourt flares,
3. persisting forecourt flares and
4. permanent forecourt flares

divided. Afterwards is considered to forecourt flares as paroxysmal, if it ends within seven days after assumed beginning spontaneously. Persisting it is called, if it continues longer than seven days or is terminated by medicamentous or electrical Kardioversion. As permanent forecourt flares one classifies, if a Kardioversion remained unsuccessful or or appears not successful.

Depending upon pulse frequency also in Bradyarrhythmia absoluta (pulse under 50 impacts per minute), standard-frequent absolute Arrhythmie (pulse 50 to 100 impacts per minute) and Tachyarrhythmia are divided for forecourt flares absoluta (pulse over 100 impacts per minute).

If the time admits is, on which forecourt flares began, can also between vagal (usually during the night) and sympathoton (often with stress, physical effort or in the morning after rising) released forecourt flares be differentiated.

Pathophysiology

In the normal condition, i.e. with sine rhythm, the forecourts and chambers of the heart directly successively for instance 70-mal per minute are stimulated (see structure and excitation line system of the heart). The muscle contraction of the forecourts leads to an additional blood filling of the chambers, which contract about 150 milliseconds later likewise. This function of the forecourts is comparable with the one injection pump with the engine and increases the impact volume of the Herzkammern by approx. 15%.

With forecourt flares however the forecourts with a frequency are stimulated from 350 to 600 per minute. This leads to snap and of unordered, sometimes hardly perceptible movements its walls, flickering.

Substantial consequences of the forecourt flickering are:

• Irregular pulse (absolute Arrhythmie or Arrhythmia absoluta). The braking and filter function of the AV-knot leads up per minute of the 350-600 forecourt impulses in irregular distances only about 100 to 160 to the chambers.
• To fast pulse (tachycardia) in the untreated condition. The AV-knot usually protects the Herzkammern against pulse frequencies over 200 per minute, in addition, the then typical frequencies from 100 to 160 per minute are not economic for the heart in the long term and can lead over weeks to a heart myasthenia with heart insufficiency.
• Easy restriction of the pumping performance of the heart by the loss of the arranged forecourt contraction. This can however likewise lead to a usually only easy degradation of the maximum stress, with before-damaged hearts to a relevant heart insufficiency.
• Increased risk for Embolien. In the forecourts (preferentially in the left Herzohr) due to the changed blood river more easily Blutgerinnsel (Thromben) can form. This Thromben again can separate and lead then in the body to embolischen container catches. Impact accumulations are particularly feared by Hirnembolien.

Causes

Can occur to forecourt flares without a recognizable cause (idiopathisch) or without recognizable basic illness (lone atrial fibrillation). This is more frequent with for instance a third of the patients the case, with paroxysmalem (approx. 45%) than with permanent forecourt flares (approx. 25%). About 20-30% of the patients suffer from one koronaren heart illness, likewise about 20-30% at a blood high pressure, scarcely 20% at a heart flap error and about 15% at a heart muscle illness. The most frequent extrakardiale cause of forecourt flares with approximately 0.5-3% of the patients is communist manifestos or also only latent hyperactivity of the thyroid (Hyperthyreose) with a five to sixfold increased risk for forecourt flares.

Electricalphysiologically essentially two mechanisms are made for for forecourt flares responsible:

• So-called Triggerarrhythmien (atriale extrasystoles and high frequency fokale atriale tachycardias) as trip, those their origin often in one the Lungenvenen has and
• circling excitations on the basis of anatomical and electricalphysiological characteristics of the forecourts, which favour the emergence and maintenance of forecourt flares.

Besides can lead also forecourt flutter, other Arrhythmien and the influence of the heart frequency by the autonomous nervous system to forecourt flares. Interestingly enough that leads forecourt flares themselves mainly by a of the atrialen and a slowing down of the atrialen excitation line too "„adaptation processes "“of the forecourts (atrial remodeling), which can keep upright for their part to forecourt flares ("„forecourt flares maintains forecourt flares "“).

Only in the last years referring to a genetic assessment for forecourt flares were found:

• in the years 2002 and 2003 independently one was described usually autosomal dominant left mutation at the gene KCNQ1, which leads so the occurrence of forecourt flares to a increased river of potassium ions during repolarization and favoured.
• 2004 published Fox and Mitarb. the results of a prospektiven study at 2243 descendants of the Framingham heart study, which among other things pointed out a twice as high risk for forecourt flares, if at least one parents had already forecourt flares.

Epidemiology and prognosis

Data to the frequency of forecourt flares in Western Europe are today meager and non-uniform until, the available data are derived predominantly from US-American data or originate from studies with patients already gotten sick. It is safe that forecourt flares the most frequent continuous heartbeat disturbance is and altogether with 0,4-2% of the total population is observed. The rises age-dependent from less than 1% with under to approximately 6% with over and 8-10% with over Forecourt flares is somewhat more frequent with men than with women of the same age.

The risk for forecourt flares rises with the severity level of existing heart illnesses considerably. Thus one found a of 4%, in the stages with the heart insufficiency in the stage NYHA I NYHA II and III of approximately 25% and in the stage NYHA IV one of 50%.

The mortality is about twice as high with forecourt flares as with of the same age ones with normal heart rhythm, which is to due however outweighing or exclusive to the more frequent heart illnesses. Annually about 6% of the patients with forecourt flares on the average suffer an impact accumulation, 15-20% of all impact accumulations occur with forecourt flares.