Tako-Tsubo syndrome in an anaesthetised patient undergoing arthroscopic knee surgery

We present a case of stress-induced myocardial stunning, also known as Tako-Tsubo syndrome, in an anaesthetised patient undergoing arthroscopic replacement of the cruciate ligament. The patient's (44 y male, ASA class II) had a history of hypertension with no other known disease. He underwent a femoral nerve block with 20 ml of 0.5% ropivacaine before receiving a balanced general anaesthesia (propofol induction, sevoflurane maintenance, 10 microg/kg sufentanil). Ten min after the beginning of surgery during endoscopic intra-articular manipulation, the patient suffered from bradycardia and hypotension; following the administration of ephedrine and atropine, he developed tachycardia, hypertension and ST segment depression. Subsequently, his systemic blood pressure dropped necessitating inotropic drug support and--later--intraaortic balloon counterpulsation; a TEE revealed no evidence of hypovolemia, anterior and antero-septal hypokinesia with an ejection fraction of 25%. Surgery was finished whilst stabilising the patient haemodynamically. Postoperative cardiac enzymes showed little elevation, an emergency coronary angiogram apical akinesia with typical ballooning and basal hyperkinesias, compatible with Tako-Tsubo syndrome. The patient's postoperative course was uneventful. We theorize that stress caused by sudden surgical pain stimulus (introduction of the endoscope into the articulation), superficial anaesthesia and insufficient analgesia created a stressful event which probably might have caused a catecholamine surge as basis of Tako-Tsubo syndrome.