Innovations: Technology and Techniques in Cardiothoracic and Vascular Surgery

Hybrid coronary revascularization (HCR) is a treatment strategy for the revascularization of multivessel coronary disease that combines the advantages of both minimally invasive surgical techniques and percutaneous coronary intervention (PCI). The optimal sequence by which revascularization should be accomplished has not been determined. We investigated clinical outcomes in a series of patients planned for HCR via robotically assisted totally endoscopic coronary artery bypass (TECAB) and standard PCI based on revascularization sequence.

A total of 238 patients planned for HCR between 2001 and 2011 were divided into three groups based on treatment sequence: (a) TECAB before PCI, (b) PCI before TECAB, and (c) same-session procedure. Multiple procedural and clinical end points before discharge and up to 2 years after the procedure were compared between the three groups in an intention-to-treat analysis. Demographic features were reviewed to determine baseline differences between each group.

Of the 238 patients, 175 (73.5%) underwent TECAB before PCI, 38 patients (16.0%) underwent PCI before TECAB, and 25 (10.5%) underwent a simultaneous revascularization procedure. At baseline, the patients undergoing TECAB before PCI were significantly older. There was a significantly higher incidence of previous myocardial infarction in the PCI-first group (P < 0.001). There was a significant difference in intensive care unit (ICU) length of stay (LOS), with shorter ICU stays in the simultaneous revascularization group (P = 0.031) and shorter hospital LOS in the PCI before TECAB group (P = 0.021).

In conclusion, revascularization sequence did not dramatically impact clinical outcomes in our observational study. The patients undergoing PCI-first and same-session interventions had shorter hospital and ICU LOS compared with the patients undergoing surgery first. Our findings suggest that no revascularization approach is arbitrarily superior and that revascularization sequence should be individualized on the basis of patient presentation and anatomical considerations.

Hybrid coronary revascularization (HCR) is a treatment strategy for the revascularization of multivessel coronary disease that combines the advantages of both minimally invasive surgical techniques and percutaneous coronary intervention (PCI). The optimal sequence by which revascularization should be accomplished has not been determined. We investigated clinical outcomes in a series of patients planned for HCR via robotically assisted totally endoscopic coronary artery bypass (TECAB) and standard PCI based on revascularization sequence.

A total of 238 patients planned for HCR between 2001 and 2011 were divided into three groups based on treatment sequence: (a) TECAB before PCI, (b) PCI before TECAB, and (c) same-session procedure. Multiple procedural and clinical end points before discharge and up to 2 years after the procedure were compared between the three groups in an intention-to-treat analysis. Demographic features were reviewed to determine baseline differences between each group.

Of the 238 patients, 175 (73.5%) underwent TECAB before PCI, 38 patients (16.0%) underwent PCI before TECAB, and 25 (10.5%) underwent a simultaneous revascularization procedure. At baseline, the patients undergoing TECAB before PCI were significantly older. There was a significantly higher incidence of previous myocardial infarction in the PCI-first group (P < 0.001). There was a significant difference in intensive care unit (ICU) length of stay (LOS), with shorter ICU stays in the simultaneous revascularization group (P = 0.031) and shorter hospital LOS in the PCI before TECAB group (P = 0.021).

In conclusion, revascularization sequence did not dramatically impact clinical outcomes in our observational study. The patients undergoing PCI-first and same-session interventions had shorter hospital and ICU LOS compared with the patients undergoing surgery first. Our findings suggest that no revascularization approach is arbitrarily superior and that revascularization sequence should be individualized on the basis of patient presentation and anatomical considerations.

Although robotic technology has addressed many of the limitations of traditional videoscopic surgery, robotic surgery has not gained widespread acceptance in the general thoracic community. We report our initial robotic surgery experience and propose a structured, competency-based pathway for the development of robotic skills.

Between December 2008 and February 2012, a total of 79 robot-assisted pulmonary, mediastinal, benign esophageal, or diaphragmatic procedures were performed. Data on patient characteristics and perioperative outcomes were retrospectively collected and analyzed. During the study period, one surgeon and three residents participated in a triphasic, competency-based pathway designed to teach robotic skills. The pathway consisted of individual preclinical learning followed by mentored preclinical exercises and progressive clinical responsibility.

The robot-assisted procedures performed included lung resection (n = 38), mediastinal mass resection (n = 19), hiatal or para-esophageal hernia repair (n = 12), and Heller myotomy (n = 7), among others (n = 3). There were no perioperative mortalities, with a 20% complication rate and a 3% readmission rate. Conversion to a thoracoscopic or open approach was required in eight pulmonary resections to facilitate dissection (six) or to control hemorrhage (two). Fewer major perioperative complications were observed in the later half of the experience. All residents who participated in the thoracic surgery robotic pathway perform robot-assisted procedures as part of their clinical practice.

Robot-assisted thoracic surgery can be safely learned when skill acquisition is guided by a structured, competency-based pathway.

Although robotic technology has addressed many of the limitations of traditional videoscopic surgery, robotic surgery has not gained widespread acceptance in the general thoracic community. We report our initial robotic surgery experience and propose a structured, competency-based pathway for the development of robotic skills.

Between December 2008 and February 2012, a total of 79 robot-assisted pulmonary, mediastinal, benign esophageal, or diaphragmatic procedures were performed. Data on patient characteristics and perioperative outcomes were retrospectively collected and analyzed. During the study period, one surgeon and three residents participated in a triphasic, competency-based pathway designed to teach robotic skills. The pathway consisted of individual preclinical learning followed by mentored preclinical exercises and progressive clinical responsibility.

The robot-assisted procedures performed included lung resection (n = 38), mediastinal mass resection (n = 19), hiatal or para-esophageal hernia repair (n = 12), and Heller myotomy (n = 7), among others (n = 3). There were no perioperative mortalities, with a 20% complication rate and a 3% readmission rate. Conversion to a thoracoscopic or open approach was required in eight pulmonary resections to facilitate dissection (six) or to control hemorrhage (two). Fewer major perioperative complications were observed in the later half of the experience. All residents who participated in the thoracic surgery robotic pathway perform robot-assisted procedures as part of their clinical practice.

Robot-assisted thoracic surgery can be safely learned when skill acquisition is guided by a structured, competency-based pathway.

Atrial fibrillation (AF) management suggests that women do not tolerate medication rhythm control strategies as well as men do; however, AF percutaneous catheter ablation has been found to be favorable. The study purpose was to compare the sex-based outcomes for patients who undergo the Cox-Maze procedure for AF.

Data were collected through our AF surgical ablation registry. Rhythm was verified by electrocardiogram and 24-hour holter at 6 and 12 months. General health-related quality of life (Short-Form 12) and specific AF symptom burden (Atrial Fibrillation Symptom Checklist: Frequency and Severity, version 3) were obtained at baseline and 12 months.

Since 2005, a total of 540 patients have undergone a Cox-Maze procedure (34% were women). The women presented with higher operative risk [additive European System for Cardiac Operative Risk Evaluation (EuroSCORE), 6.71 ± 2.61 vs 5.25 ± 2.80, t = 5.85, P < 0.001], higher rates of congestive heart failure (49% vs 32%, P < 0.001), and more concomitant mitral valve procedures (32% vs 19%, P = 0.001). Perioperative outcomes were similar. Return to sinus rhythm off antiarrhythmics were not different at 6 and 12 months (78% vs 75%, P = 0.53, and 81% vs 80%, P = 1.00, respectively). Cumulative 2-year survival (93.9% for the men and 89.3% for the women) was not different for all-cause mortality (hazard ratio, 1.47; confidence interval, 0.68–3.21; P = 0.33) and cardiac-related mortality [women: 10/14 (71%) vs men 7/11 (64%), P = 1.00]. Health-related quality of life showed significant improvement; AF symptoms significantly decreased across the sexes.

Outcomes after the Cox-Maze procedure are similar across sex. Atrial fibrillation surgical ablation should be considered a treatment option for women—it is safe and effective, improves general health-related quality of life, and reduces AF symptom burden.

Atrial fibrillation (AF) management suggests that women do not tolerate medication rhythm control strategies as well as men do; however, AF percutaneous catheter ablation has been found to be favorable. The study purpose was to compare the sex-based outcomes for patients who undergo the Cox-Maze procedure for AF.

Data were collected through our AF surgical ablation registry. Rhythm was verified by electrocardiogram and 24-hour holter at 6 and 12 months. General health-related quality of life (Short-Form 12) and specific AF symptom burden (Atrial Fibrillation Symptom Checklist: Frequency and Severity, version 3) were obtained at baseline and 12 months.

Since 2005, a total of 540 patients have undergone a Cox-Maze procedure (34% were women). The women presented with higher operative risk [additive European System for Cardiac Operative Risk Evaluation (EuroSCORE), 6.71 ± 2.61 vs 5.25 ± 2.80, t = 5.85, P < 0.001], higher rates of congestive heart failure (49% vs 32%, P < 0.001), and more concomitant mitral valve procedures (32% vs 19%, P = 0.001). Perioperative outcomes were similar. Return to sinus rhythm off antiarrhythmics were not different at 6 and 12 months (78% vs 75%, P = 0.53, and 81% vs 80%, P = 1.00, respectively). Cumulative 2-year survival (93.9% for the men and 89.3% for the women) was not different for all-cause mortality (hazard ratio, 1.47; confidence interval, 0.68–3.21; P = 0.33) and cardiac-related mortality [women: 10/14 (71%) vs men 7/11 (64%), P = 1.00]. Health-related quality of life showed significant improvement; AF symptoms significantly decreased across the sexes.

Outcomes after the Cox-Maze procedure are similar across sex. Atrial fibrillation surgical ablation should be considered a treatment option for women—it is safe and effective, improves general health-related quality of life, and reduces AF symptom burden.

The purpose of this study was to determine the effect of three-dimensional (3D) binocular, stereoscopic, and two-dimensional (2D) monocular visualization on robotics-assisted mitral valve annuloplasty versus conventional techniques in an ex vivo animal model. In addition, we sought to determine whether these effects were consistent between novices and experts in robotics-assisted cardiac surgery.

A cardiac surgery test-bed was constructed to measure forces applied during mitral valve annuloplasty. Sutures were passed through the porcine mitral valve annulus by the participants with different levels of experience in robotics-assisted surgery and tied in place using both robotics-assisted and conventional surgery techniques.

The mean time for both the experts and the novices using 3D visualization was significantly less than that required using 2D vision (P < 0.001). However, there was no significant difference in the maximum force applied by the novices to the mitral valve during suturing (P = 0.7) and suture tying (P = 0.6) using either 2D or 3D visualization. The mean time required and forces applied by both the experts and the novices were significantly less using the conventional surgical technique than when using the robotic system with either 2D or 3D vision (P < 0.001).

Despite high-quality binocular images, both the experts and the novices applied significantly more force to the cardiac tissue during 3D robotics-assisted mitral valve annuloplasty than during conventional open mitral valve annuloplasty. This finding suggests that 3D visualization does not fully compensate for the absence of haptic feedback in robotics-assisted cardiac surgery.

The purpose of this study was to determine the effect of three-dimensional (3D) binocular, stereoscopic, and two-dimensional (2D) monocular visualization on robotics-assisted mitral valve annuloplasty versus conventional techniques in an ex vivo animal model. In addition, we sought to determine whether these effects were consistent between novices and experts in robotics-assisted cardiac surgery.

A cardiac surgery test-bed was constructed to measure forces applied during mitral valve annuloplasty. Sutures were passed through the porcine mitral valve annulus by the participants with different levels of experience in robotics-assisted surgery and tied in place using both robotics-assisted and conventional surgery techniques.

The mean time for both the experts and the novices using 3D visualization was significantly less than that required using 2D vision (P < 0.001). However, there was no significant difference in the maximum force applied by the novices to the mitral valve during suturing (P = 0.7) and suture tying (P = 0.6) using either 2D or 3D visualization. The mean time required and forces applied by both the experts and the novices were significantly less using the conventional surgical technique than when using the robotic system with either 2D or 3D vision (P < 0.001).

Despite high-quality binocular images, both the experts and the novices applied significantly more force to the cardiac tissue during 3D robotics-assisted mitral valve annuloplasty than during conventional open mitral valve annuloplasty. This finding suggests that 3D visualization does not fully compensate for the absence of haptic feedback in robotics-assisted cardiac surgery.

Although pectus excavatum repair has evolved to a minimally invasive technique in prepubescent patients, the best approach in adults is less clearly understood. The aim of this study was to identify the preoperative characteristics, operative variables, and postoperative outcomes in adult patients with pectus excavatum undergoing thoracoscopic repair using different bar stabilizers compared with the open surgical repair.

We conducted a prospective study between July 2009 and July 2012 in a single institution. Thirty-one patients (26 men and 5 women) aged 18 to 35 years were randomly assigned into three groups: group A, 9 patients underwent modified Ravitch repair; group B, 11 patients underwent video-assisted thoracoscopic repair using metal stabilizers; and group C, 11 patients underwent video-assisted thoracoscopic repair using absorbable stabilizers. Preoperative, intraoperative, and postoperative variables are compared between all groups.

In all groups, the preoperative variables were well matched for age, sex, and Haller index. Operative time was 2 hours longer in group A (P = 0.0001). There was no intraoperative complication. Length of hospital stay was 4 days shorter in group A. Morbidity was 23% and composed of pneumothorax (three), wound seroma (two), pleural effusion (one), and stabilizer break (one), occurring more frequently in groups B and C. There was no perioperative mortality. All patients were satisfied with the cosmetic results.

Repair of pectus excavatum in adult patients can be performed effectively through either open surgical technique or thoracoscopy, with no intraoperative complications and with excellent immediate results. Although the operative time for the Ravitch repair was longer, the hospital stay was significantly shorter than that for the video-assisted method.

Although pectus excavatum repair has evolved to a minimally invasive technique in prepubescent patients, the best approach in adults is less clearly understood. The aim of this study was to identify the preoperative characteristics, operative variables, and postoperative outcomes in adult patients with pectus excavatum undergoing thoracoscopic repair using different bar stabilizers compared with the open surgical repair.

We conducted a prospective study between July 2009 and July 2012 in a single institution. Thirty-one patients (26 men and 5 women) aged 18 to 35 years were randomly assigned into three groups: group A, 9 patients underwent modified Ravitch repair; group B, 11 patients underwent video-assisted thoracoscopic repair using metal stabilizers; and group C, 11 patients underwent video-assisted thoracoscopic repair using absorbable stabilizers. Preoperative, intraoperative, and postoperative variables are compared between all groups.

In all groups, the preoperative variables were well matched for age, sex, and Haller index. Operative time was 2 hours longer in group A (P = 0.0001). There was no intraoperative complication. Length of hospital stay was 4 days shorter in group A. Morbidity was 23% and composed of pneumothorax (three), wound seroma (two), pleural effusion (one), and stabilizer break (one), occurring more frequently in groups B and C. There was no perioperative mortality. All patients were satisfied with the cosmetic results.

Repair of pectus excavatum in adult patients can be performed effectively through either open surgical technique or thoracoscopy, with no intraoperative complications and with excellent immediate results. Although the operative time for the Ravitch repair was longer, the hospital stay was significantly shorter than that for the video-assisted method.

The aim of this study was to assess early graft patency in eSVS Mesh–covered saphenous vein grafts (SVGs) in patients undergoing coronary artery bypass grafting.

In 20 patients meeting criteria for double arterial grafting to the left-sided coronary system and eSVS Mesh–covered SVG to the right-sided coronary system, patency was evaluated intraoperatively by transit time flow measurement and at 5 days postoperatively by computed tomographic angiography.

Twenty patients underwent 49 arterial and 22 venous grafts (mean, 3.55/patient) using off-pump techniques. All grafts were determined to be patent intraoperatively. On computed tomographic angiography, arterial graft patency was 100%. In one venous anastomosis, the distal limb of a sequential graft was occluded, for an overall patency rate of 95%.

The eSVS Mesh does not compromise early SVG patency.

The aim of this study was to assess early graft patency in eSVS Mesh–covered saphenous vein grafts (SVGs) in patients undergoing coronary artery bypass grafting.

In 20 patients meeting criteria for double arterial grafting to the left-sided coronary system and eSVS Mesh–covered SVG to the right-sided coronary system, patency was evaluated intraoperatively by transit time flow measurement and at 5 days postoperatively by computed tomographic angiography.

Twenty patients underwent 49 arterial and 22 venous grafts (mean, 3.55/patient) using off-pump techniques. All grafts were determined to be patent intraoperatively. On computed tomographic angiography, arterial graft patency was 100%. In one venous anastomosis, the distal limb of a sequential graft was occluded, for an overall patency rate of 95%.

The eSVS Mesh does not compromise early SVG patency.

Few studies to date have evaluated the videothoracoscopic approach of the internal thoracic lymphatic chain. However, the histological evaluation of lymph nodes is essential for patients with breast cancer who show lymph node uptake at scintigraphy in the preoperative period and also for patients with lymphoma who have exclusive uptake in these lymph nodes at positron emission tomography for recurrence assessment. Our goal was to evaluate the safety and the change in oncologic approach through this minimally invasive technique.

This is a review of the prospectively collected data in a group of patients undergoing thoracoscopic biopsy of the thoracic lymphatic chain in patients with breast cancer and lymphoma carried out in our institution between September 2010 and June 2012. The analyzed variables include age, histological type, operated hemithorax, number of resected lymph nodes, neoplastic involvement of the resected lymph nodes, duration of chest tube drainage, length of hospital stay, and perioperative mortality. Complications such as subcutaneous emphysema and necessity for blood transfusion were also evaluated.

Thoracoscopic biopsy was successfully performed in 16 patients, of whom 14 had breast cancer and 2 had lymphoma. The surgical biopsy results changed the treatment in the two patients with lymphoma and avoided radiotherapy in the eight patients with breast cancer who did not have metastases.

The use of the thoracoscopic assessment of the internal thoracic lymphatic chain seems safe and resulted in therapy modification in more than half of our patients, suggesting that it is an effective technique for staging in selected breast cancer and lymphoma cases.

Few studies to date have evaluated the videothoracoscopic approach of the internal thoracic lymphatic chain. However, the histological evaluation of lymph nodes is essential for patients with breast cancer who show lymph node uptake at scintigraphy in the preoperative period and also for patients with lymphoma who have exclusive uptake in these lymph nodes at positron emission tomography for recurrence assessment. Our goal was to evaluate the safety and the change in oncologic approach through this minimally invasive technique.

This is a review of the prospectively collected data in a group of patients undergoing thoracoscopic biopsy of the thoracic lymphatic chain in patients with breast cancer and lymphoma carried out in our institution between September 2010 and June 2012. The analyzed variables include age, histological type, operated hemithorax, number of resected lymph nodes, neoplastic involvement of the resected lymph nodes, duration of chest tube drainage, length of hospital stay, and perioperative mortality. Complications such as subcutaneous emphysema and necessity for blood transfusion were also evaluated.

Thoracoscopic biopsy was successfully performed in 16 patients, of whom 14 had breast cancer and 2 had lymphoma. The surgical biopsy results changed the treatment in the two patients with lymphoma and avoided radiotherapy in the eight patients with breast cancer who did not have metastases.

The use of the thoracoscopic assessment of the internal thoracic lymphatic chain seems safe and resulted in therapy modification in more than half of our patients, suggesting that it is an effective technique for staging in selected breast cancer and lymphoma cases.

Mediastinitis is a severe complication of cardiac surgery. Sternal instability is concomitantly present in most cases. Broken steel wires may cause sternal instability. In this study, the role of broken steel wires in sternal closure was evaluated in patients who developed poststernotomy mediastinitis.

Preoperative, perioperative, and postoperative data of patients who underwent thoracic surgery between 1996 and 2006 were retrieved from the SUMMIT registry database. Patients needing reoperation for mediastinitis were identified. Patients’ charts and chest radiographs from initial surgery to reoperation for mediastinitis were reviewed.

Forty-five patients developed postoperative mediastinitis needing reoperation (0.6%). Because of loss to follow-up, 31 patients were evaluated. Eight patients (25.8%) presented fractured steel wires. Most of the broken steel wires (87.5%) manifested at the cranial site of figure-of-eight configurations. In the patients without broken steel wires, mediastinitis manifested after 14 days compared with 38 days in the patients with broken wires. Time until mediastinitis was not significantly different (P = 0.229). The mean time until steel wire disruption was 14 days (range, 4–48 days).

Broken steel wires were observed before mediastinitis became manifest. Fracturing occurred mainly at the cranial site of figure-of-eight configurations. The results of the present study emphasize that closure technique plays a prominent role in the development of mediastinitis. Because mediastinitis is associated with an increased risk for early morbidity, attention should be paid to patients presenting with broken steel wires. New techniques for median sternotomy closure are needed that are less prone to mechanical fatigue than are steel wires.

Mediastinitis is a severe complication of cardiac surgery. Sternal instability is concomitantly present in most cases. Broken steel wires may cause sternal instability. In this study, the role of broken steel wires in sternal closure was evaluated in patients who developed poststernotomy mediastinitis.

Preoperative, perioperative, and postoperative data of patients who underwent thoracic surgery between 1996 and 2006 were retrieved from the SUMMIT registry database. Patients needing reoperation for mediastinitis were identified. Patients’ charts and chest radiographs from initial surgery to reoperation for mediastinitis were reviewed.

Forty-five patients developed postoperative mediastinitis needing reoperation (0.6%). Because of loss to follow-up, 31 patients were evaluated. Eight patients (25.8%) presented fractured steel wires. Most of the broken steel wires (87.5%) manifested at the cranial site of figure-of-eight configurations. In the patients without broken steel wires, mediastinitis manifested after 14 days compared with 38 days in the patients with broken wires. Time until mediastinitis was not significantly different (P = 0.229). The mean time until steel wire disruption was 14 days (range, 4–48 days).

Broken steel wires were observed before mediastinitis became manifest. Fracturing occurred mainly at the cranial site of figure-of-eight configurations. The results of the present study emphasize that closure technique plays a prominent role in the development of mediastinitis. Because mediastinitis is associated with an increased risk for early morbidity, attention should be paid to patients presenting with broken steel wires. New techniques for median sternotomy closure are needed that are less prone to mechanical fatigue than are steel wires.

Obesity is highly prevalent in modern patient populations. Several studies have published conflicting outcomes after minimally invasive surgery with regard to morbidity and mortality. Some instances consider obesity as a relative contraindication for this approach because of inadequate exposure of the surgical field. Our aim was to investigate the outcomes of minimally invasive mitral valve surgery through a right lateral minithoracotomy in patients with a body mass index (BMI) of 30 kg/m² or greater.

We conducted a retrospective database review between January 1, 2009, and December 31, 2011. Preoperative, intraoperative, postoperative, and follow-up data of 225 consecutive patients were collected.

The patients were stratified according to their BMI: 108 had a normal weight with a BMI of lower than 25 kg/m² (18–24), 90 were overweight with a BMI of 25 to 29 kg/m², and 27 were obese with a BMI of 30 kg/m² (30–41) or greater. Statistical analysis showed significantly longer ventilation times in the obese group, whereas all other variables were similar. Survival, major adverse cardiac and cerebrovascular event-free survival, valve competency, and freedom from reoperation were also comparable.

Our data suggest that obesity should not deter a surgeon from selecting a minimally invasive approach. Despite longer postoperative ventilation times, a BMI of 30 kg/m² or greater does not influence short- and medium-term outcome. Obese patients may even benefit from this approach because it avoids the need for sternotomy and therefore reduces the risk for sternal wound infection.

Obesity is highly prevalent in modern patient populations. Several studies have published conflicting outcomes after minimally invasive surgery with regard to morbidity and mortality. Some instances consider obesity as a relative contraindication for this approach because of inadequate exposure of the surgical field. Our aim was to investigate the outcomes of minimally invasive mitral valve surgery through a right lateral minithoracotomy in patients with a body mass index (BMI) of 30 kg/m² or greater.

We conducted a retrospective database review between January 1, 2009, and December 31, 2011. Preoperative, intraoperative, postoperative, and follow-up data of 225 consecutive patients were collected.

The patients were stratified according to their BMI: 108 had a normal weight with a BMI of lower than 25 kg/m² (18–24), 90 were overweight with a BMI of 25 to 29 kg/m², and 27 were obese with a BMI of 30 kg/m² (30–41) or greater. Statistical analysis showed significantly longer ventilation times in the obese group, whereas all other variables were similar. Survival, major adverse cardiac and cerebrovascular event-free survival, valve competency, and freedom from reoperation were also comparable.

Our data suggest that obesity should not deter a surgeon from selecting a minimally invasive approach. Despite longer postoperative ventilation times, a BMI of 30 kg/m² or greater does not influence short- and medium-term outcome. Obese patients may even benefit from this approach because it avoids the need for sternotomy and therefore reduces the risk for sternal wound infection.

This study was designed to compare neurological injury–associated protein S100β release during three different treatment modalities, minimized closed circuit coronary artery bypass grafting (CABG) (MCABG), off-pump CABG (OPCAB), and conventional CABG (CCABG), comprising high-volume prime and cold crystalloid cardioplegia. Our working hypothesis was that fluid restriction as provided by MCABG may decrease neurological injury–associated protein S100β release.

In this prospective trial, in a tertiary center, 30 surgical patients (aged >70 years, 25 men and 5 women) undergoing first-time elective CABG were enrolled. The inclusion criteria were three-vessel disease and elective surgery. The exclusion criteria were left ventricular ejection fraction of less than 30%, use of clopidogrel, carotid disease, or needing fewer than three distal anastomoses. Protein S100β concentrations, hematocrit (Ht) levels, and PO₂ levels were measured after induction of anesthesia, 10 minutes after reperfusion, upon arrival at the intensive care unit, 3 hours postoperatively at the intensive care unit, and the next morning. Statistics consisted of areas under the curve, peak levels, and correlation and variance tests.

A significant negative correlation was found indicating higher S100β release at lower Ht levels and at lower PO₂ levels in all study groups. The lowest S100β variance was measured during MCABG (Wilks Λ P = 0.052). The perioperative Ht was significantly higher in the MCABG group and in the OPCAB group compared with the CCABG group (P = 0.04 vs P < 0.01). At all time points, the S100β protein concentration showed no significant differences between the different surgical techniques. The mean (95% confidence interval) values of S100 area under the curve were the following: CCABG, 2.3 (1.06–3.5); MCABG, 1.44 (0.6–2.21); and OPCAB, 1.87 (1.5–2.19) [independent nonparametric Kruskal-Wallis test (P = 0.13)]. The mean (95% confidence interval) peak S100 values (calculated as the maximum value seen in a patient during the research period) were the following: CCABG, 1.07 (0.4–1.68); MCABG, 0.59 (0.28–0.90); and OPCAB, 0.83 (0.59–1.06) [independent nonparametric Kruskal-Wallis test (P = 0.22)].

Despite similar perioperative S100β protein release for all techniques studied, higher Ht and PO₂ levels correlated with lower S100β release within all study groups. The low S100β variance during the fluid restrictive MCABG technique may be due to more efficient oxygen transport to the brain provided by significantly higher perioperative Ht levels. Further prospective data are required to better understand this complex issue.

This study was designed to compare neurological injury–associated protein S100β release during three different treatment modalities, minimized closed circuit coronary artery bypass grafting (CABG) (MCABG), off-pump CABG (OPCAB), and conventional CABG (CCABG), comprising high-volume prime and cold crystalloid cardioplegia. Our working hypothesis was that fluid restriction as provided by MCABG may decrease neurological injury–associated protein S100β release.

In this prospective trial, in a tertiary center, 30 surgical patients (aged >70 years, 25 men and 5 women) undergoing first-time elective CABG were enrolled. The inclusion criteria were three-vessel disease and elective surgery. The exclusion criteria were left ventricular ejection fraction of less than 30%, use of clopidogrel, carotid disease, or needing fewer than three distal anastomoses. Protein S100β concentrations, hematocrit (Ht) levels, and PO₂ levels were measured after induction of anesthesia, 10 minutes after reperfusion, upon arrival at the intensive care unit, 3 hours postoperatively at the intensive care unit, and the next morning. Statistics consisted of areas under the curve, peak levels, and correlation and variance tests.

A significant negative correlation was found indicating higher S100β release at lower Ht levels and at lower PO₂ levels in all study groups. The lowest S100β variance was measured during MCABG (Wilks Λ P = 0.052). The perioperative Ht was significantly higher in the MCABG group and in the OPCAB group compared with the CCABG group (P = 0.04 vs P < 0.01). At all time points, the S100β protein concentration showed no significant differences between the different surgical techniques. The mean (95% confidence interval) values of S100 area under the curve were the following: CCABG, 2.3 (1.06–3.5); MCABG, 1.44 (0.6–2.21); and OPCAB, 1.87 (1.5–2.19) [independent nonparametric Kruskal-Wallis test (P = 0.13)]. The mean (95% confidence interval) peak S100 values (calculated as the maximum value seen in a patient during the research period) were the following: CCABG, 1.07 (0.4–1.68); MCABG, 0.59 (0.28–0.90); and OPCAB, 0.83 (0.59–1.06) [independent nonparametric Kruskal-Wallis test (P = 0.22)].

Despite similar perioperative S100β protein release for all techniques studied, higher Ht and PO₂ levels correlated with lower S100β release within all study groups. The low S100β variance during the fluid restrictive MCABG technique may be due to more efficient oxygen transport to the brain provided by significantly higher perioperative Ht levels. Further prospective data are required to better understand this complex issue.