[The "Mickey Mouse Heart"].

The "Mickey Mouse Heart" Abstract. The "Mickey Mouse Heart" describes patients with a combination of HFpEF, massive biatrial dilatation and dilatation of the mitral- and tricuspid annulus, atrial fibrillation and severe mitral- and tricuspid regurgitation. Most frequently elderly patients with HFpEF are affected by this syndrome. The underlying molecular mechanisms or risk factors for the typical biatrial dilatation are unknown. The guideline-directed heart failure therapy as well as the evaluation of early rhythm control for atrial fibrillation and the treatment of mitral- and tricuspid regurgitation are recommended.