Aims: We aimed to evaluate possible detrimental effects of transoesophageal echocardiography (TEE) on the oesophageal tissue during percutaneous mitral valve repair (PMVR).

Methods and results: From March 2014 to July 2015, 186 patients were treated for severe mitral regurgitation with PMVR using the MitraClip system. In 40 patients, oesophago-gastro-duodenoscopy was performed due to symptoms related to the gastrointestinal tract. Based on the procedure duration, patients were classified into group 1 (> 60 minutes, n= 23) or into group 2 (< 60 minutes, n= 17), respectively. Oesophageal lesions (OL) were found in 19 patients (group 1: n= 17 vs. group 2: n= 2, p< 0.0001). We observed a change in leucocyte count after the procedure (group 1:+ 2.00 Gpt/L [SEM±0.48] vs. group 2:+ 0.54 Gpt/L [SEM±0.36], p= 0.028). This change was more apparent when comparing patients with OL vs. those without (lesions:+ 2.65 Gpt/L [SEM±0.56] vs. no lesions:+ 0.23 Gpt/L [SEM±0.12], p< 0.0001).

Conclusions: Prolonged use of TEE during PMVR with a procedure time of longer than 60 minutes increases the risk of oesophageal damage. An exceptional rise of leucocyte count after PMVR may raise suspicion of new oesophageal damage.