Is left atrial appendage occlusion useful for prevention of stroke or embolism in atrial fibrillation?

Abstract

Since in atrial fibrillation more than 90% of the thrombi are located in the left atrial appendage, an "elimination" of the left atrial appendage, either by resection or occlusion, seems an attractive alternative to oral anticoagulation. Although frequently regarded as an useless appendage, data from animal and human investigations show that the left atrial appendage may play an important role in the maintenance and regulation of the cardiac function, especially in arterial hypertension, atrial fibrillation, coronary heart disease, valvular heart disease and heart failure. Elimination of the left atrial appendage may impede thirst in hypovolemia, deteriorate hemodynamic responses to volume or pressure overload, decrease cardiac output and promote heart failure. Instead of preventing stroke, the consequences of left atrial appendage elimination may create new risk factors for stroke and thus might induce more harm than benefit to patients with atrial fibrillation. As long as the physiologic and pathophysiologic role of the left atrial appendage is not fully understood, left atrial appendage elimination should not be an alternative to oral anticoagulation.

Orale Antikoagulation bei Herzinsuffizienz

“…Als eine sichere Indikation für die Antikoagulation gilt ein begleitendes Vorhofflimmern [27][28][29][30][31]. Obwohl prospektive Daten zum Risiko thromboembolischer Ereignisse in diesen klinischen Situationen fehlen, gelten stattgehabte Thromboembolien und nachgewiesene intrakardiale Thromben als akzeptierte Indikation für eine antithrombotische Therapie.…”

“…Diese Begleiterkrankungen können die Thrombogenität des Bluts verstärken und Interaktionen oder einen veränderten Metabolismus oraler Antikoagulanzien bewirken. [23][24][25][26][27][28][29][30][31]. Daher müssen sich die Empfehlungen zur Antikoagulation gegenwärtig an der individuellen Einschätzung des Nutzen-Risiko-Verhältnisses sowie an Daten aus kleineren unkontrollierten Studien und Subgruppenanalysen größerer Herzinsuffizienzstudien orientieren, bis Ergebnisse aus laufenden oder angekündi-gten kontrollierten Studien zur Verfügung stehen.…”

Anticoagulation in atrial fibrillation and flutter

“…Because 90% of atrial thrombi in non-rheumatic AF are found in the left atrial appendage (LAA) [8], occlusion or resection of the LAA seems an alternative to anti-coagulation in the prevention of thromboembolic events in some patients. A newly developed device allowing percutaneous LAA occlusion (PLAATO) might be an alternative to oral anticoagulation for patients with a high thromboembolic risk and a contraindication to anticoagulation [38], and its value is currently being assessed.…”

Left Atrial Appendage Exclusion for Stroke Prevention in Patients With Nonrheumatic Atrial Fibrillation

“…Thus, LAA occlusion may contribute to the altered left atrial compliance. 40 Reduced atrial natriuretic peptide release and water retention was observed in patients with bilateral atrial appendectomy. 41 On the other hand, preserving the right atrial appendage may attenuate this effect.…”