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A b s t r a c tBackground: Remote preconditioning has been shown to be a potent protective phenomenon in many animals. Several studies aimed to demonstrate it was feasible in humans by trying to show its protective effect during cardiac surgery. Of these, some small studies and one larger trial were positive while two other bigger studies showed no effectiveness of remote preconditioning as assessed by levels of postoperatively released cardiac markers. Recently, two large clinical trials also failed to prove the benefit of remote preconditioning in cardiac surgery. No study showed that remote preconditioning actually increases resistance of human myocardium to standardised ischaemic and reperfusion stimulus in experimental settings. In animal studies, remote preconditioning was shown to improve mitochondrial function and structure, but such data on human myocardium are scarce. Aim:The aim of the study is to determine whether remote preconditioning protects human myocardium against ischaemia-reperfusion injury in both in vivo and in vitro conditions. Methods:The trial is designed as a single-centre, double-blinded, sham-controlled trial of 120 patients. We randomise (1:1) patients referred for coronary artery bypass grafting for stable coronary artery disease to remote preconditioning or "sham" intervention. The remote preconditioning is obtained by three cycles of 5 min inflation and 5 min deflation of a blood pressure cuff on the right arm. Postoperative course including myocardial enzymes profile will be analysed. Moreover, in the in-vitro arm the clinically preconditioned myocardium will be assessed for function, mitochondria structure, and mitochondria-dependent apoptosis. The informed consent of all patients is obtained before enrolment into the study by the investigator. The study conforms to the spirit and the letter of the declaration of Helsinki. Results and conclusions:In case the effect of remote preconditioning is not measurable in ex-vivo assessment, any future attempt at implementing this phenomenon in clinical practice may be futile and should not be continued until the effect can be confirmed in a controlled experimental setting. The study might therefore indicate future directions in trials of clinical implementation of remote preconditioning. INTRODUCTIONNo experimental study showed that human myocardium can be remotely preconditioned against standardised ischaemic/hypoxic insult. We aim to remove this major knowledge gap by applying remote preconditioning to the patient and studying ex-vivo the myocardium obtained thereafter. We assume that we will be able to show that remote preconditioning by brief periods of ischaemia of the arm protects segments of human right atrial appendage myocardium subjected to simulated hypoxia and reoxygenation in-vitro.This proof of principle is crucial. In case the effect of remote preconditioning is not measurable in ex-vivo assessment, any future attempt at implementing this phenomenon in clinical practice may be futile and should not be continued until the e...

Introduction Over the last two decades transcatheter aortic valve replacement (TAVR) has been approved for clinical use. The anaesthetic choice for this procedure is evolving. General anaesthesia was the predominant anaesthetic technique. Growing experience and advances in technology and economic considerations have led to an increasing interest in performing TAVR under monitored sedation. Aim The assessment of monitored sedation, called cooperative sedation, involves pharmacologically mediated suppression of consciousness and preservation of verbal contact in response to stimulation as a safe method of anaesthesia for TAVR. Material and methods Sixty out of 63 TAVR patients with femoral access received monitored sedation. Dexmedetomidine was administered in most of such cases (46 patients). A questionnaire was also carried out by staff involved in performing TAVR procedures, with more than 5 years of experience in it, concerning the method of anaesthesia and perioperative care. Results Conversion to general anaesthesia was required in 10% of patients (6 cases), only one as a patient-related complication (hypercarbia). The questionnaire carried out showed that anaesthesia and postoperative care after TAVR are underestimated. Conclusions The preliminary results regarding anaesthetic management in TAVR procedures demonstrate that monitored sedation is safe, provided that contraindications are observed.

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IntroductionSignificant impairment of left ventricular function causes low cardiac output syndrome in the immediate postoperative period in 3–14% of patients undergoing surgery, increasing the mortality 15-fold.AimTo assess the use of levosimendan in patients undergoing cardiac surgery in 2016.Material and methodsThe analysis included 14 patients: 3 (21.4%) women and 11 (78.6%) men aged 65.4 ±11.8 years. The mean value of left ventricular ejection fraction amounted to 20 ±6.25%. In 11 patients, levosimendan infusion was started immediately after the induction of anesthesia. Three patients received the agent during the early postoperative period due to low cardiac output syndrome refractory to conventional therapy. The dosage was modified within the range of 0.05–0.2 μg/kg/min. On the day of the surgery, all patients received continuous infusion of adrenaline and levonor.ResultsThe cardiac index amounted to 2.8 ±0.71 l/m2 after several hours of infusion and 2.9 ±0.1 l/m2 the next morning. The first examination showed that the mean systemic vascular resistance was 1010 dyn/s–5 and the second: 940 ±100 dyn/s–5; mixed venous blood saturation amounted to 66 ±7.5% and 65.5 ±8%, respectively. Respectively, the mean concentration of lactates was 2.0 ±0.96 mmol/l and 1.8 ±0.24 mmol/l. Mechanical lung ventilation lasting more than 48 hours was required in 50% of the patients. Two patients with chronic kidney disease required bedside renal replacement therapy before the procedure. Two (14.3%) patients died. Nine (64.3%) patients were discharged home, and three were transferred to cardiac wards.ConclusionsLevosimendan therapy proved safe in the study group. The nature of the study and the small sample size preclude the formulation of detailed conclusions.