Stone heart syndrome after prolonged cardioplegia induced cardiac arrest in open-heart surgery - a pilot study on pigs.

OBJECTIVES: To investigate Stone Heart Syndrome (SHS) as consequence of prolonged ischemic arrest in an experimental study on pigs in regards to onset of SHS and pathological changes. Outcomes defined as aortic cross clamp (ACC) time until onset of SHS and cellular changes characterized by SHS. METHODS: Eight pigs were included to undergo normothermic cardioplegia induced cardiac arrest ranging from 80 to 240 minutes of ACC. Duration of ACC was defined as time from initiation of aortic cross clamping until cessation. Normothermic, cardioplegic solution administered directly into the arterial system, though in a reduced dose compared to clinical practice. Myocardial contracture evaluated by palpation of the myocardium. Biopsies were collected from the left ventricle just after the induction of cardiac arrest and after reperfusion. Biopsies were evaluated for pathological changes indicative of SHS by electron microscopy. RESULTS: Six pigs completed the full trial, while two were lost to bleeding. Pigs undergoing 80 to 120 minutes of ACC regained heart rhythm either spontaneously or after defibrillation. Pigs undergoing more than 180 minutes of ACC had contracted hearts with no electrocardiographic response indicating the development of SHS. Electron microscopy findings after ACC of 80 to 120 minutes showed no or low degrees of cellular changes, whereas pig hearts with more than 180 minutes of ACC showed severe mitochondrial changes, endothelial damage, and shortening of sarcomeres consistent with SHS. CONCLUSION: Development of SHS in pigs was ACC time dependent and solely avoided when ACC was limited to a maximum of 120 minutes.

[The post-thrombotic syndrome and its endovascular treatment].

Post-thrombotic syndrome (PTS) is a complication after deep venous thrombosis, causing considerable disability in affected patients. In this review, we present the aetiology, pathophysiology, risk factors and diagnosis of PTS and discuss different treatments with a special focus on endovascular treatment for iliac vein obstruction, which is documented as a safe, effective and durable treatment for severe PTS. Although treatment of PTS in Denmark currently only is based on conservative strategy, we would like to encourage, that endovascular treatment should be considered as a treatment option in these patients.