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Objectives: The benefit of off-pump coronary artery bypass (OPCAB) surgery may be reduced by strokes caused by microemboli produced after aortic side-clamping for proximal bypass anastomoses. The Heartstring device allows constructing proximal bypass anastomoses without side-clamping of the aorta., Methods: This retrospective study describes 260 consecutive patients who underwent OPCAB surgery; 442 proximal anastomoses were performed with the Heartstring device in this series. Ten percent of the patients were randomly sampled before discharge to undergo a coronary angiogram for assessment of graft patency., Results: Intraoperative Doppler measurements confirmed regular bypass function. Early mortality occurred in 4 patients (1.5%), and stroke occurred in 2 patients (0.8%). Device-related bleeding was negligible, and there were no cases of aortic dissection. Perioperative ischemia occurred in 8 patients (3.1%). Predischarge coronary angiography evaluations in 25 of the patients (of 260) showed that all 42 Heartstring-assisted anastomoses (of 442) were patent., Conclusions: Clampless performance of proximal bypass anastomoses combined with OPCAB is associated with a very low incidence of stroke complications. Short-term follow-up has shown excellent results regarding bypass patency and other adverse events. Prospective randomized trials are required to confirm the advantage of this technique.

Background: Anesthetic gases modulate gene expression and provide organ protection. This study aimed at identifying myocardial transcriptional phenotypes to predict cardiovascular biomarkers and function in patients undergoing off-pump coronary artery bypass graft surgery., Methods: In a prospective randomized trial, patients undergoing elective off-pump coronary artery bypass graft surgery were allocated to receive either the anesthetic gas sevoflurane (n = 10) or the intravenous anesthetic propofol (n = 10). Blood samples were collected perioperatively to determine cardiac troponin T, N-terminal pro-brain natriuretic peptide, and pregnancy-associated plasma protein A. Cardiac function was measured with transesophageal echocardiography and pulmonary artery thermodilution. Atrial biopsies were collected at the beginning and end of bypass surgery to determine gene expression profiles., Results: N-terminal pro-brain natriuretic peptide and pregnancy-associated plasma protein A blood levels were decreased with sevoflurane treatment. Echocardiography showed preserved postoperative cardiac function in sevoflurane patients, which paralleled higher cardiac index measurements. N-terminal pro-brain natriuretic peptide release was predicted by sevoflurane-induced transcriptional reduction in fatty acid oxidation, whereas changes in cardiac index were predicted by preoperative gene activity of the peroxisome proliferator-activated receptor gamma coactivator-1alpha pathway. Sevoflurane-mediated attenuation of transcripts involved in DNA-damage signaling and activation of the granulocyte colony-stimulating factor survival pathway predicted improved postoperative cardiac index and diastolic heart function, respectively., Conclusions: Anesthetic-induced and constitutive gene regulatory control of myocardial substrate metabolism predicts postoperative cardiac function in patients undergoing off-pump coronary artery bypass graft surgery. The authors' analysis further points to novel cardiac survival pathways as potential therapeutic targets in perioperative cardioprotection.

The new Volumetric Ejection Fraction monitoring system (VoLEF), when combined with the Pulse Contour Cardiac Output monitoring system (PiCCO) system, allows measurement of left and right heart end-diastolic volumes by thermodilution. The aim of this study was to evaluate whether the left heart end-diastolic volume index determined by the VoLEF system (LHEDI) better reflects left ventricular end-diastolic area index (LVEDAI) measured by transoesophageal echocardiography than does global end-diastolic volume index (GEDI) measured by the PiCCO system alone. Following induction of anaesthesia, PiCCO, VoLEF and transoesophageal echocardiography measurements were performed before and after a fluid challenge in 20 patients scheduled for elective cardiac surgery. Both left ventricular end-diastolic area index and global end-diastolic volume index, but not left heart end-diastolic volume index, significantly increased after fluid administration. Mean bias +/- 2 SD for DeltaLHEDI-DeltaLVEDAI was -2.2 +/- 32.0% and for DeltaGEDI-DeltaLVEDAI -0.6 +/- 16.8%. In contrast to global end-diastolic volume index, the use of left heart end-diastolic volume index determined by the VoLEF system cannot be recommended as an estimate of left ventricular preload.

Study Objectives: Stroke volume variation (SVV) and pulse pressure variation (PPV) determined by the PiCCOplus system (Pulsion Medical Systems; Munich, Germany) may be useful dynamic variables in guiding fluid therapy in patients receiving mechanical ventilation. However, with respect to the prediction of volume responsiveness, conflicting results for SVV have been published in cardiac surgery patients. The goal of this study was to reevaluate SVV in predicting volume responsiveness and to compare it with PPV., Design: Prospective nonrandomized clinical investigation., Setting: University-based cardiac surgery., Patients: Forty patients with preserved left ventricular function undergoing elective off-pump coronary artery bypass grafting., Interventions: Volume replacement therapy before surgery., Measurements and Results: Following induction of anesthesia, before and after volume replacement (6% hydroxyethyl starch solution, 10 mL/kg ideal body weight), hemodynamic measurements of stroke volume index (SVI), SVV, PPV, global end-diastolic volume index (GEDVI), central venous pressure (CVP) and pulmonary capillary wedge pressure (PCWP) were obtained. Also, left ventricular end-diastolic area index (LVEDAI) was assessed by transesophageal echocardiography. Prediction of ventricular performance was tested by calculating the area under the receiver operating characteristic (ROC) curves and by linear regression analysis; p < 0.05 was considered significant. All measured hemodynamic variables except heart rate changed significantly after fluid loading. GEDVI, CVP, PCWP, and LVEDAI increased, whereas SVV and PPV decreased. The best area under the ROC curve (AUC) was found for SVV (AUC = 0.823) and PPV (AUC = 0.808); the AUC for other preload indexes ranged from 0.493 to 0.636. A significant correlation with changes of SVI was observed for SVV (r = 0.606, p < 0.001) and PPV (r = 0.612, p < 0.001) only. SVV and PPV were closely related (r = 0.861, p < 0.001)., Conclusions: In contrast to standard preload indexes, SVV and PPV, comparably, showed a good performance in predicting fluid responsiveness in patients before off-pump coronary artery bypass grafting.