[Function of the left atrial appendage after electrical cardioversion of atrial fibrillation to sinus rhythm]

It is widely believed that atrial fibrillation appears in a secondly manner to atrial enlargement. Morfological alteration might be the source of disturbance of electrical activation and mechanical function to fibres that facilitate arrhythmia preservation as well as life threatening complications.

It is crucial to establish whether reversion of atrial fibrillation to sinus rhythm causes size diminishment and function improvement of the left atrial appendage, which creates hope to avoid dangerous complications, particularly systemic embolisation. DATA AND METHODOLOGY: 30 patients were qualified including 18 males and 12 females aged between 52 and 86 (average age was 63.81 +/- 9.22). All the patients suffered from nonrheumatic atrial fibrillation. The echocardiographic examination was conducted before reversion of atrial fibrillation, right after reaching sinus rhythm and after 6 months observation at sustained sinus rhythm. During the transesophageal echocardiographic examination the following parameters were investigated: LAApodł, LAApoprz, LAAobw, LAApole, LAAF, LAAB, LAAF intg, LAAB intg, spontaneous echocardiographic contrast, thrombus.

Left atrial appendage size right after reversion of atrial fibrillation did not considerably differ from the values registered at the time of arrhythmia. It significantly diminished in the case of sustained stabilisation of sinus rhythm. The diminishment of the left atrial appendage size was connected with its function improvement expressed by increased maximum filling and emptying velocities as well as their integrals. SEC appearance frequency considerably increased right after reaching sinus rhythm. SEC appeared very rarely in the examination after 6 months. No single case of THR in LAA was noted. At the same time several cases of THR were disclosed both before and directly after restoration of sinus rhythm.

Sinus rhythm restoration and its sustaining for a longer period of time results in size diminishing and function improvement of left atrial appendage. The stability of sinus rhythm is closely tied with thromboembolism risk factors.