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During surgery with cardiopulmonary bypass (CPB), maintaining adequate cerebral blood flow (CBF) is paramount to prevent adverse neurological outcome; tissue damage can occur if CBF reduction is sufficient to impair energy metabolism. Ten adult patients undergoing cardiothoracic surgery with CPB received perfusion and metabolic neuromonitoring using a novel optical system combining diffuse correlation spectroscopy and broadband near-infrared spectroscopy. CPB onset resulted in large increases in CBF and significant drops in mean arterial pressure and metabolism. No changes were observed transitioning off CPB. Real-time assessment of cerebral perfusion and metabolism could alert clinicians to relevant hemodynamic events before brain injury occurs.

Background Pulsatile perfusion may offer microcirculatory advantages over conventional nonpulsatile perfusion during cardiopulmonary bypass (CPB). Here, we present direct visual evidence of microvascular perfusion and vasoreactivity between perfusion modalities. Methods A prospective, randomized cohort study of 20 high-risk cardiac surgical patients undergoing pulsatile (n = 10) or nonpulsatile (n = 10) flow during CPB was conducted. Changes in sublingual mucosal microcirculation were assessed with orthogonal polarization spectral imaging along with near-infrared spectroscopic indices of thenar muscle tissue oxygen saturation (StO 2 ) and its recovery during a vascular occlusion test at the following time points: baseline (T 0 ), 30 minutes on CPB (T 1 ), 90 minutes on CPB (T 2 ), 1 hour after CPB (T 3 ), and 24 hours after CPB (T 4 ). Results On the basis of our scoring scale, a shift in microcirculatory blood flow occurred over time. The pulsatile group maintained normal perfusion characteristics, whereas the nonpulsatile group exhibited deterioration in perfusion during CPB (T 2 : 74.0% ± 5.6% versus 57.6% ± 5.0%) and after CPB (T 3 : 76.2% ± 2.7% versus 58.9% ± 5.2%, T 4 : 85.7% ± 2.6% versus 69.8% ± 5.9%). Concurrently, no important differences were found between groups in baseline StO 2 and consumption slope at all time points. Reperfusion slope was substantially different between groups 24 hours after CPB (T 4 : 6.1% ± 0.6% versus 3.7% ± 0.5%), indicating improved microvascular responsiveness in the pulsatile group versus the nonpulsatile group. Conclusions Pulsatility generated by the roller pump during CPB improves microcirculatory blood flow and tissue oxygen saturation compared with nonpulsatile flow in high-risk cardiac surgical patients, which may reflect attenuation of the systemic inflammatory response and ischemia–reperfusion injury.

Objective Aortic valve replacement is the standard of care for severe, symptomatic aortic valve stenosis (AS); however, anatomy or preexisting comorbidities may preclude conventional or alternative transcatheter approaches. Aortic valve bypass (AVB) may be performed as a salvage procedure for the relief of symptomatic aortic stenosis in patients who are not suitable candidates for aortic valve replacement. Methods At our institution, seven patients underwent AVB using the Correx automated coring and apical connector system. All patients had severe AS with New York Heart Association functional class 3 symptoms and were not candidates for conventional or transcatheter approaches. Via a left anterolateral thoracotomy to access the descending aorta and left ventricular apex, we used the Correx system (Correx, Waltham, MA USA) to anastomose a valve conduit to the left ventricular apex proximally and the descending aorta distally. Three patients required cardiopulmonary bypass. Results In all seven patients, the automated coring and apical connector was successfully deployed. There were two in-hospital deaths in this series. Immediately postoperatively and at 3 months, there was a significant reduction in mean and peak valve gradients, and all surviving patients performed at New York Heart Association functional class 1. Conclusions Aortic valve bypass seems to be an acceptable alternative for the treatment of severe AS in high-risk patients who are not candidates for aortic valve replacement. The Correx automated system may improve the clinical applicability and surgical repro-ducibility of AVB in appropriately selected patients in which conventional or transcatheter aortic valve replacement is not a feasible options.

Background Although often short-lived and self-limiting, postoperative atrial fibrillation (POAF) is a well-recognized postoperative complication of cardiac surgery and is associated with a 2-fold increase in cardiovascular mortality and morbidity. Objective Our aim was to determine whether intraoperative bilateral pulmonary vein radiofrequency ablation decreases the incidence of POAF in patients undergoing coronary artery bypass grafting (CABG). Methods A total of 175 patients undergoing CABG was prospectively randomized to undergo adjuvant bilateral radiofrequency pulmonary vein ablation in addition to CABG (group A; n=89) or CABG alone (group B; n=86). Intraoperative pulmonary vein isolation was confirmed by the inability to pace the heart via the pulmonary veins after ablation. All patients received postoperative β-blocker. Results There was no difference in the incidence of POAF in the treatment group who underwent adjuvant pulmonary vein ablation (group A; 37.1%) compared with the control group who did not (group B; 36.1%) ( P = .887). There were no differences in postoperative inotropic support, antiarrhythmic drug use, need for oral anticoagulation, and complication rates. The mean length of postoperative hospital stay was 8.2 ± 6.5 days in the ablation group and 6.7 ± 4.6 days in the control group ( P Conclusion Adjuvant pulmonary vein isolation does not decrease the incidence of POAF or its clinical impact but increases the mean length of stay in the hospital. The mechanism of POAF does not appear to depend on the pulmonary veins.

Introduction: Ascertaining the biological age of patients with advanced vascular disease could advance risk assessment and management. The extent to which telomeres shorten in leukocytes could be a marker of biological age because it reflects the accumulation of replication stresses imposed on leukocyte progenitors. However, because of wide, genetic variability in leukocyte telomere length (TL), a single leukocyte TL measurement does not reliably indicate telomere shortening. Hypothesis: We hypothesized that the difference in length of telomeres in “non-replicating” muscle-rich tissue and that of circulating leukocytes provides a patient-specific index of telomere shortening in patients with advanced vascular disease. Methods: TL in leukocytes, skeletal muscle, and right atrial cardiac muscle were measured from 134 patients undergoing coronary or thoracic aortic surgery, using quantitative polymerase chain reaction. Relationships between leukocyte TL or the muscle-leukocyte TL difference (ΔTL) and early post-operative outcomes were tested using Cox proportional hazard and binary logistic regression analyses. Results: Telomeres in cardiac muscle and skeletal muscle were significantly longer than those in leukocytes (p Conclusions: Right atrium-leukocyte ΔTL provides an index of telomere shortening and may inform outcomes in patients with advanced vascular disease. This two-component telomere measurement may reflect the biological age of individuals with chronic vascular disease.

Objectives The complexity of surgical treatment for acute type A dissection contributes to the variability in patient management. This study was designed to elucidate the contemporary practice preferences of cardiac surgeons regarding different phases of management of acute type A aortic dissection. Methods A 34-item questionnaire was distributed to all Canadian adult cardiac surgeons addressing the preoperative, intraoperative, and postoperative management of acute type A dissection. A total of 100 responses were obtained (82% of active surgeons in Canada). Outcomes were compared between high- and low-volume aortic surgeons. Results Seventy-six percent of respondents favored axillary artery cannulation. High-volume surgeons (>150 cases) were more likely to indicate a target lowest nasopharyngeal temperature more than 20°C (53% vs 25%, P = .02). The majority of surgeons (65%) recommended using selective antegrade cerebral perfusion, with a significantly greater proportion for higher-volume aortic surgeons ( P = .03). In addition, high-volume aortic surgeons were more likely to recommend aortic root replacement at smaller diameters (73% vs 55%, P = .02), to recommend more extensive distal aortic resection with routine open hemiarch anastomosis (85% vs 65%, P = .04), and to more commonly perform total arch reconstruction when needed (93% vs 77%, P = .04). In the follow-up period, frequency of serial imaging of the residual aorta was significantly higher for high-volume aortic surgeons ( P = .04). Conclusions This study identified some commonalities in practice preferences among Canadian cardiac surgeons for the management of acute type A aortic dissection. However, it also highlighted significant differences in temperature management, cerebral protection strategies, and extent of resection between high-volume and low-volume aortic surgeons.