The invention relates to the use of a phosphodiesterase type III (PDE III) inhibitor or Ca2+-sensitizing agent or a pharmaceutically acceptable derivative thereof for the preparation of a medication for the reduction of the heart size of a patient suffering from heart failure.本發明係關於第III型磷酸二酯酶(phosphodieSterase type III;PDE III)抑制劑或Ca2+增敏劑或其醫藥學上可接受之衍生物用於製備降低罹患心臟衰竭之患者之心臟大小的藥物之用途。