[Conduction anesthesia in patients with heart diseases].

The effect of epidural/spinal anaesthesia on cardiovascular function results from blockade of the sympathetic nervous system and secondly from plasma absorption of local anaesthetic agents. Patients suffering from preexisting heart diseases may have different responses to epidural or spinal anaesthesia. In patients with myocardial ischemia, the decrease in myocardial work and the reduction in heart rate induced by cervical or thoracic epidural anaesthesia improve the myocardial oxygen balance. Changes in the inotropic state induced by thoracic epidural anaesthesia may worsen the haemodynamic condition of patients with heart failure. When the spread of the epidural blockade is limited to the lower segments (< T12), changes are limited. In high risk patients, the haemodynamic advantages of a combined technique (general plus epidural anaesthesia) and the protective effect on the occurrence of myocardial ischemia and related complications are a matter of interest. Part of the beneficial effect of epidural anaesthesia could be related to postoperative analgesia and its effects on stress response and haemostasis.