Background: Newly diagnosed  clinically significant tricuspid regurgitation (TR) is a quite common clinical problem and requires a concise diagnostic approach. Sometimes a piece of painstaking detective work is necessary to find the cause of TR.
Case summary: We report on a 72-year-old female patient who presented with new onset of dyspnea on exertion for 2 weeks and pitting ankle edema. Prehospital transthoracic echocardiography showed grade III/V TR and was suspicious for thrombi in both right atrium (RA) and right ventricle (RV) as a cause for TR. Transesophageal echocardiography (TEE) revealed 2 elongated structures in RA and RV passing the tricuspid valve (TV) (Fig. 1). Chest X-ray was suggestive that both structures were parts of a lost guide wire after prior insertion of a central venous catheter. An attempt to retrieve the foreign bodies with a goose neck snare catheter (Fig 3) was only partly successful resulting in defragmentation of the foreign body without full removal. However, follow-up TEE showed that no foreign bodies were passing the TV (Fig 2) and TR was reduced to grade I/V with remaining fragments in the RA. Similar findings were found on cardiac computed tomography (CCT)(Fig 4). Because of the small size of the fragments remaining in the RA and the presence of only mild TR after the intervention surgical removal was dismissed. Density of the remaining material in CCT was 470 Hounsfield units which does not fit to a metallic wire but rather to bone cement (PMMA Polymethyl Methacrylat). Indeed, our patient had a kyphoplasty 4 years before clinical presentation and a previous CT after that procedure already showed the elongated structures in RA/RV (Fig 5).

Bone cement (PMMA) leakage into the paravertebral or extradural venous plexus is a rare but well-described complication during kyphoplasty when cement is injected into the vertebral body under high pressure via a small needle. A needle inadvertently placed in the basivertebral vein or an overfilling of cement in the vertebral body can facilitate cement migration into the perivertebral venous plexus which may embolize via the hemiazygous vein, the azygous vein and finally the inferior vena cava (IVC) to the RA and RV.

Conclusion: This case shows an unusual cause of TR caused by a rare complication of spinal surgery. Extravasation of PMMA during kyphoplasty is an uncommon but quite typical event. Due to significant TR an interventional attempt to remove the intracardiac PMMA may be a feasible alternative to open cardiac surgery with good functional results.

Fig 1 TOE on admission showing two longitudinal structures passing by the  TV
Fig 2 TOE after intervention showing the absence of any structures in the orificium of TV
Fig 3 Fluoroscopy during intervention showing a short fragment in the RA (black arrow) and a long fragment in the RV (red arrow).
Fig 4. Postinterventional cardiac CT failed to show any fragments in the RV. DES of RCA (green arrow).
Fig 5 CT scan showing  a longitudinal structure in the RV. The scan was performed 4 years prior to clinical presentation after extensive kyphoplasty as can be seen in thoracic segment of the patient’s spine.