Spontaneous intracardiac microcavitations in a patient with a colonic carcinoma

Intracardiac microcavitations consist of airy microbubbles. They are typically found in patients with an intravascular line or device, mechanical heart valves or in decompression sickness. We report a case of a patient in mid-70s who was admitted due to weakness in both legs, left-thoracic pain and fever. Despite the lack of any of the risk factors mentioned above, spontaneous microcavitations were detected in the right sided cardiac cavities. After the detection of liver lesions suspicious for a metastatic disease, a colonoscopy was performed. An ulcerated colonic carcinoma at the ileocoecal valve was diagnosed and highly suspicious for being the entry port of the microcavitations. This unusual presentation of microcavitations together with a colonic neoplasia leads to hypotheses about the journey of the microbubbles from the ascending colon into the right heart. Gastrointestinal tumours are described as being the causes of microbubbles. Translocation of microbubbles through hepatopulmonary shunting are described in the context of locally applied particles of similar size during radioembolisation. A thorough aetiological workup is of importance since the underlying cause is potentially dangerous due to its own nature of disease and due the complications of the microcavitations such as paradoxical emboli or pulmonary sequelae.