A large number of intra-abdominal and extra-abdominal diseases may give rise to abdominal symptoms. Two patients are discussed who presented with abdominal pain due to severe heart failure. Initially, this diagnosis was overlooked, since abdominal complaints are rarely the primary symptoms of this condition. The authors argue that heart failure, the overall prevalence of which is increasing, should be considered in the differential diagnosis of any patient who presents with abdominal pain. In addition, they propose a systematic diagnostic approach for reaching an individualised diagnosis and therapy directed at heart failure.