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Cardiopulmonary bypass triggers systemic inflammation and systemic oxidative stress. Recent reports suggest that continuous ventilation during cardiopulmonary bypass (CPB) can affect the outcome of patients after cardiac surgery. We investigated the influence of lung ventilation on inflammatory and oxidative stress markers during coronary artery bypass graft (CABG) with CPB in 13 patients with (Group 2) or without (Group 1) ventilation of the lungs with small tidal volume (4 ml/kg). IL-10 and elastase in blood were elevated in both groups with a peak at the end of CPB (P

Objective: Cardiac surgery may lead to severe oxidative stress due to formation of oxidation products generated during ischemia and reperfusion. We investigated to which extent oxidative stress influences a number of endogenous antioxidants and markers of cellular activation. Methods: At six time points blood was withdrawn from patients undergoing coronary artery bypass grafting, using the on-pump procedure. Results: Both glutathione peroxidase and superoxide dismutase show a gradual and strong increase in activity during surgery (40 and 30%, respectively), returning to baseline values 24 h after surgery. The total antioxidant capacity has a maximum increase of 60%. Markers of cellular activation, such as eosinophil cationic protein and tryptase also increase during the procedure. Conclusion: Cardiac surgery results in systemic inflammation accompanied or caused by severe oxidative stress. The human body has a strong innate oxidative defence screen, which is probably not sufficient to fully compensate for the total amount of oxidative damage. q 2004 Elsevier B.V. All rights reserved.

Background Experimental studies have related the cardioprotective effects of sevoflurane both to preconditioning properties and to beneficial effects during reperfusion. In clinical studies, the cardioprotective effects of volatile agents seem more important when administered throughout the procedure than when used only in the preconditioning period. The authors hypothesized that the cardioprotective effects of sevoflurane observed in patients undergoing coronary surgery with cardiopulmonary bypass are related to timing and duration of its administration. Methods Elective coronary surgery patients were randomly assigned to four different anesthetic protocols (n = 50 each). In a first group, patients received a propofol based intravenous regimen (propofol group). In a second group, propofol was replaced by sevoflurane from sternotomy until the start of cardiopulmonary bypass (SEVO pre group). In a third group, propofol was replaced by sevoflurane after completion of the coronary anastomoses (SEVO post group). In a fourth group, propofol was administered until sternotomy and then replaced by sevoflurane for the remaining of the operation (SEVO all group). Postoperative concentrations of cardiac troponin I were followed during 48 h. Cardiac function was assessed perioperatively and during 24 h postoperatively. Results Postoperative troponin I concentrations in the SEVO all group were lower than in the propofol group. Stroke volume decreased transiently after cardiopulmonary bypass in the propofol group but remained unchanged throughout in the SEVO all group. In the SEVO pre and SEVO post groups, stroke volume also decreased after cardiopulmonary bypass but returned earlier to baseline values than in the propofol group. Duration of stay in the intensive care unit was lower in the SEVO all group than in the propofol group. Conclusion In patients undergoing coronary artery surgery with cardiopulmonary bypass, the cardioprotective effects of sevoflurane were clinically most apparent when it was administered throughout the operation.

Background Volatile anesthetics protect the myocardium during coronary surgery. This study hypothesized that the use of a volatile agent in the anesthetic regimen would be associated with a shorter intensive care unit (ICU) and hospital length of stay (LOS), compared with a total intravenous anesthetic regimen. Methods Elective coronary surgery patients were randomly assigned to receive propofol (n = 80), midazolam (n = 80), sevoflurane (n = 80), or desflurane (n = 80) as part of a remifentanil-based anesthetic regimen. Multiple logistic regression analysis was used to identify the independent variables associated with a prolonged ICU LOS. Results Patient characteristics were similar in all groups. ICU and hospital LOS were lower in the sevoflurane and desflurane groups (P < 0.01). The number of patients who needed a prolonged ICU stay (> 48 h) was also significantly lower (propofol: n = 31; midazolam: n = 34; sevoflurane: n = 10; desflurane: n = 15; P < 0.01). Occurrence of atrial fibrillation, a postoperative troponin I concentration greater than 4 ng/ml, and the need for prolonged inotropic support (> 12 h) were identified as the significant risk factors for prolonged ICU LOS. Postoperative troponin I concentrations and need for prolonged inotropic support were lower in the sevoflurane and desflurane group (P < 0.01). Postoperative cardiac function was also better preserved with the volatile anesthetics. The incidence of other postoperative complications was similar in all groups. Conclusions The use of sevoflurane and desflurane resulted in a shorter ICU and hospital LOS. This seemed to be related to a better preservation of early postoperative myocardial function.

Background The present study investigated the effects of propofol, desflurane, and sevoflurane on recovery of myocardial function in high-risk coronary surgery patients. High-risk patients were defined as those older than 70 yr with three-vessel disease and an ejection fraction less than 50% with impaired length-dependent regulation of myocardial function. Methods Coronary surgery patients (n = 45) were randomly assigned to receive either target-controlled infusion of propofol or inhalational anesthesia with desflurane or sevoflurane. Cardiac function was assessed perioperatively and during 24 h postoperatively using a Swan-Ganz catheter. Perioperatively, a high-fidelity pressure catheter was positioned in the left and right atrium and ventricle. Response to increased cardiac load, obtained by leg elevation, was assessed before and after cardiopulmonary bypass (CPB). Effects on contraction were evaluated by analysis of changes in dP/dt(max). Effects on relaxation were assessed by analysis of the load-dependence of myocardial relaxation. Postoperative levels of cardiac troponin I were followed for 36 h. Results After CPB, cardiac index and dP/dt(max) were significantly lower in patients under propofol anesthesia. Post-CPB, leg elevation resulted in a significantly greater decrease in dP/dt(max) in the propofol group, whereas the responses in the desflurane and sevoflurane groups were comparable with the responses before CPB. After CPB, load dependence of left ventricular pressure drop was significantly higher in the propofol group than in the desflurane and sevoflurane group. Troponin I levels were significantly higher in the propofol group. Conclusions Sevoflurane and desflurane but not propofol preserved left ventricular function after CPB in high-risk coronary surgery patients with less evidence of myocardial damage postoperatively.

Two patients with chronic sternal osteomyelitis after an initially uncomplicated coronary artery bypass grafting (CABG) operation are described. Chronic osteomyelitis, caused in both cases by Pseudomonas aeruginosa, occurred six and four months after CABG respectively. Because chronic infection failed to respond to local wound care and medical therapy, more radical treatment was needed. Steel wires were removed and surgical debridement was performed. In one patient, an additional omental transposition was performed. In both cases radical debridement in combination with antibiotics successfully eradicated the infection.

Objective The Abiomed BVS 5000 ventricular assist device (VAD) has been approved in Belgium for emergency cardiac support in patients with postcardiotomy failure with the aim of native heart function recovery. Other indications have emerged from world wide experience, but the indication and usefulness of emergency implantation of assist devices is often debated. Methods To decide which patients benefit most from emergency ventricular assist device implantation, we retrospectively reviewed our results of mechanical circulatory support with Abiomed in 20 patients over a 4-year period. Fifteen patients with mean age 58 +/- 6 years experienced postcardiotomy failure and underwent biventricular assist device (BVAD) implantation (group A), after elective (n = 9) or after emergency coronary artery bypass grafting (CABG) (n = 6). Five patients (group B), with mean age 35 +/- 19 years, had an implantation for other underlying conditions: hypertrophic cardiomyopathy (n = 3), myocarditis (n = 1) and primary cardiac allograft failure (n = 1). Results Of these two groups, eight and two patients respectively needed cardiopulmonary resuscitation before VAD implantation. The mean duration of support in both groups was 5.8 (range 12 h-13 days) and 4.4 days (range 2 h-9 days) respectively. Six and two patients could be weaned from the device and nine and one patients respectively, died on the device. Two patients in group B underwent successful heart transplantation and four patients in group A died after weaning. Two patients in the postcardiotomy group and four patients in group B survived (13% and 80%) with an overall survival and discharge rate of 30%. Conclusion Although sample sizes are small, better survival rates with emergency Abiomed BVS 5000 implantation were obtained in the non postcardiotomy group (group B). For patients in the postcardiotomy group, outcome was negatively influenced by cardiac arrest and resuscitation before urgent CABG. Since death is the only alternative for these patients in cardiogenic shock and organ recovery cannot be predicted, we continue to consider emergency VAD implantation in this patient population.

Background Dependence of left ventricular (LV) relaxation on cardiac systolic load is a function of myocardial contractility. The authors hypothesized that, if a tight coupling would exist between LV contraction and relaxation, the changes in relaxation rate with an increase in cardiac systolic load would be related to the changes in LV contraction. Methods Coronary surgery patients (n = 120) with preoperative ejection fraction >40% were included. High-fidelity LV pressure tracings (n = 120) and transgastric transesophageal echocardiographic data (n = 40) were obtained. Hearts were paced at a fixed rate of 90 beats/min. Effects on contraction were evaluated by analysis of changes in dP/dt(max) and stroke area. Effects on relaxation were assessed by analysis of R (slope of the relation between tau and end-systolic pressure). Correlations were calculated with linear regression analysis using Pearson's coefficient r. Results Baseline LV end-diastolic pressure was 10+/-3 mm Hg (mean +/- SD). During leg raising, systolic LV pressure increased from 93+/-9 to 107+/-11 mm Hg. The change in dP/dt(max) was variable and ranged from -181 to +254 mm Hg/s. A similar variability was observed with the changes in stroke area, which ranged from -2.0 to +5.5 cm2. Changes in dP/dt(max) and in stroke area were closely related to individual R values (r = 0.87, P Conclusions A tight coupling was observed between contraction and relaxation. Leg raising identified patients who developed a load-dependent impairment of LV performance and increased load dependence of LV relaxation.

Background Impairment of left ventricular function after cardiopulmonary bypass (CPB) is well recognized, but little is known about the time course of recovery of cardiac function early after separation from CPB. Therefore, recovery of left ventricular function was evaluated early after separation from CPB in patients undergoing coronary artery surgery. The authors tried to determine whether this recovery might be attributed to autoregulation of function by preload. Methods Left ventricular pressure was measured with fluid-filled catheters. Data were digitally recorded during increased pressure induced by elevating the legs. Transgastric short-axis echocardiographic views of the left ventricle were simultaneously recorded on videotape. Systolic function was evaluated with the slope (Ees, mmHg/ml) of the systolic pressure-volume relation. Diastolic function was evaluated with the chamber stiffness constant (Kc, ml-1) of the diastolic pressure-volume relation. Cardiac function was assessed before CPB, after termination of CPB, and 5, 10, and 15 min later. Two different separation procedures from CPB were compared: in protocol 1, left ventricular function was documented during the standard procedure (n = 24); in protocol 2, the heart was optimally filled 10 min before separation from CPB (n = 12). Results In protocol 1, Ees was 2.88 +/- 0.21 mmHg/ml (mean +/- SEM) and Kc was 0.012 +/- 0.001 ml-1 before CPB. Within 10 min after separation from CPB, Ees increased from 1.10 +/- 0.32 to 2.92 +/- 0.34 (P = 0.001) and Kc decreased from 0.022 +/- 0.002 to 0.011 +/- 0.001 (P = 0.001). The parameters remained stable thereafter. In protocol 2, Ees was 2.92 +/- 0.51 mmHg/ ml and Kc was 0.011 +/- 0.002 ml-1 before CPB. Depression of systolic and diastolic function was not observed in these patients. At time 0, Ees was 2.46 +/- 0.16 and Kc was 0.012 +/- 0.002. These values remained stable throughout the entire observation period. Conclusions Significant functional recovery was observed early after separation from CPB, which was suggestive of time-dependent changes in both systolic and diastolic left ventricular function induced by preload restoration.

Background Sevoflurane has been shown to protect against myocardial ischemia and reperfusion injury in animals. The present study investigated whether these effects were clinically relevant and would protect left ventricular (LV) function during coronary surgery. Methods Twenty coronary surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhalational anesthesia with sevoflurane. Except for this, anesthetic and surgical management was the same in all patients. A high-fidelity pressure catheter was positioned in the left ventricle and the left atrium. LV response to increased cardiac load, obtained by leg elevation, was assessed before and after cardiopulmonary bypass (CPB). Effects on contraction were evaluated by analysis of changes in dP/dt(max). Effects on relaxation were assessed by analysis of the load dependence of myocardial relaxation (R = slope of the relation between time constant tau of isovolumic relaxation and end-systolic pressure). Postoperative concentrations of cardiac troponin I were followed during 36 h. Results Before CPB, leg elevation slightly increased dP/dt(max) in the sevoflurane group (5 +/- 3%), whereas it remained unchanged in the propofol group (1 +/- 6%). After CPB, leg elevation resulted in a decrease in dP/dt(max) in the propofol group (-5 +/- 4%), whereas the response in the sevoflurane group was comparable to the response before CPB (5 +/- 4%). Load dependence of LV pressure fall (R) was similar in both groups before CPB. After CPB, R was increased in the propofol group but not in the sevoflurane group. Troponin I concentrations were significantly lower in the sevoflurane than in the propofol group. Conclusions Sevoflurane preserved LV function after CPB with less evidence of myocardial damage in the first 36 h postoperatively. These data suggest a cardioprotective effect of sevoflurane during coronary artery surgery.

The Abiomed BVS 5000 ventricular assist device (VAD) has been approved in Belgium for emergency cardiac support in patients with postcardiotomy failure with the aim of native heart function recovery. Other indications have emerged from world wide experience, but the indication and usefulness of emergency implantation of assist devices is often debated.To decide which patients benefit most from emergency ventricular assist device implantation, we retrospectively reviewed our results of mechanical circulatory support with Abiomed in 20 patients over a 4-year period. Fifteen patients with mean age 58 +/- 6 years experienced postcardiotomy failure and underwent biventricular assist device (BVAD) implantation (group A), after elective (n = 9) or after emergency coronary artery bypass grafting (CABG) (n = 6). Five patients (group B), with mean age 35 +/- 19 years, had an implantation for other underlying conditions: hypertrophic cardiomyopathy (n = 3), myocarditis (n = 1) and primary cardiac allograft failure (n = 1).Of these two groups, eight and two patients respectively needed cardiopulmonary resuscitation before VAD implantation. The mean duration of support in both groups was 5.8 (range 12 h-13 days) and 4.4 days (range 2 h-9 days) respectively. Six and two patients could be weaned from the device and nine and one patients respectively, died on the device. Two patients in group B underwent successful heart transplantation and four patients in group A died after weaning. Two patients in the postcardiotomy group and four patients in group B survived (13% and 80%) with an overall survival and discharge rate of 30%.Although sample sizes are small, better survival rates with emergency Abiomed BVS 5000 implantation were obtained in the non postcardiotomy group (group B). For patients in the postcardiotomy group, outcome was negatively influenced by cardiac arrest and resuscitation before urgent CABG. Since death is the only alternative for these patients in cardiogenic shock and organ recovery cannot be predicted, we continue to consider emergency VAD implantation in this patient population.

Background Phosphodiesterase III inhibitors increase myocardial contractility and decrease left ventricular (LV) afterload. We studied whether these effects altered LV response to an increase in cardiac load and affected length‐dependent regulation of myocardial function. Methods Before the start of cardiopulmonary bypass, a high‐fidelity pressure catheter was positioned in the left ventricle and the left atrium in 10 coronary surgery patients. LV response to an increased cardiac load, caused by leg elevation, was assessed during baseline conditions and after administration of milrinone at a dose of 20 µg kg–1 over 15 min. Effects on contraction were measured by changes in maximal rate of pressure development (dP/dtmax). Effects on relaxation were assessed by analysis of changes in maximum rate of pressure decrease and by analysis of the load dependency of myocardial relaxation (R = slope of the relation between the time constant of isovolumic relaxation and end systolic pressure). Results Milrinone increased dP/dtmax but measures of relaxation were unaltered. Leg elevation had more effect on measures of contraction and relaxation after milrinone than at baseline. The relationship between R and changes in dP/dtmax shifted downwards and to the right with milrinone, whereas the relationship between R and changes in end diastolic pressure (EDP) shifted downwards and to the left. Conclusions This suggests that milrinone improved contraction, reduced the load dependency of LV pressure decrease, and reduced the change in EDP after leg elevation. Br J Anaesth 2002: 88: 779–84

To study the usefulness and effectiveness of off-pump coronary bypass grafting with the Octopus heart stabilizing device.The files of thirty-one patients undergoing coronary artery bypass with the aid of the Octopus heart stabilizing device between April 1996 and October 1998 were studied retrospectively. Patients were divided into group A (n = 23), patients with single or double vessel disease and technically suitable coronary lesions for off-pump procedure and group B (n = 8), patients with multiple vessel disease considered to be with excessive risk for cardiopulmonary bypass due to poor general condition combined with renal failure and/or chronic obstructive pulmonary disease. Standard median sternotomy (n = 27), lateral thoracotomy (n = 1) or minithoracotomy (n = 3) were performed for access and for harvesting the left internal mammary artery (LIMA).The mean number of bypasses was 1.2 and 1.1 in groups A and B, respectively. Thirty patients received a LIMA graft to the left anterior descending artery (LAD). Homologous blood transfusions were needed in five patients (21%) in group A and four (50%) in group B. There were no wound infections or neurologic complications. All patients in group A survived and are asymptomatic. One patient in group B died of septic shock, two have residual angina pectoris or dyspnea, and five are asymptomatic.Coronary artery bypass using the Octopus heart stabilizing device proved to be a safe and effective technique resulting in complete revascularization in group A patients with no mortality. Incomplete revascularization may offer a substantial benefit to patients who cannot tolerate cardiopulmonary bypass due to poor general condition. We prefer median sternotomy, allowing precise harvesting of the internal mammary artery and more precise anastomoses without increased morbidity.

To investigate the feasability and results of endoscopic vein harvesting (EVH) using the Vasoview Uniport system (Guidant Corporation, Menlo Park,CA). Can this technique be used as a standard technique for vein harvesting in coronary artery bypass surgery (CABG) or is it too time consuming? Do smaller incisions result in less morbidity and discomfort?From October 1998 to May 1999, 158 patients who underwent CABG with venous grafts, in addition to arterial grafts, formed the study population for EVH. In group A (n=131) the vein was harvested with the Vasoview Uniport System. In group B (n=27) the vein was harvested by a conventional open technique with interrupted incisions because of unavailability of the equipment. Recordings were made on vein length, harvest time, length of incision, and complications.In none of the patients in group A was a conversion to the open technique necessary. In 72/131, pure EVH was used. In 59/131 an additional incision below the knee was used for harvesting extra vein length. Mean harvested vein graft length (cm) was 35.9 (range 18-56) in group A and 30.6 (range 16-51) in group B, and mm of vein harvested/min was 77 and 71 in group A and B. Mean time for harvesting and closing (min) was 56.1 (range 14-120) SD 20.4 and 78.3 (range 37-129) SD 26 for a mean length of incision (cm) of six (range 2-19) and 27 (range 12-54). Wound complications at postoperative day three at discharge, and after six weeks were seen in 30 (23%), 27 (20%) and four (4%) patients of group A, and in five (18%), five (18%) and four (23%) of group B.Despite a learning curve in using endoscopic techniques, the total procedural time for EHV is acceptable and even shorter than open harvesting. Most of the time is gained in closure of the wound. Hematoma formation is the most common peroperative complication, but diminishes with experience. The absence of postoperative edema after EVH is striking. Despite the higher costs for disposable material, we have adopted EVH as a standard technique since patient and surgeon satisfaction have improved substantially.

Study Objective: To study the usefulness and effectiveness of off-pump coronary bypass grafting with the Octopus heart stabilizing device. Method: The files of thirty-one patients undergoing coronary artery bypass with the aid of the Octopus heart stabilizing device between April 1996 and October 1998 were studied retrospectively. Patients were divided into group A (n = 23), patients with single or double vessel disease and technically suitable coronary lesions for off-pump procedure and group B (n = 8), patients with multiple vessel disease considered to be with excessive risk for cardiopulmonary bypass due to poor general condition combined with renal failure and/or chronic obstructive pulmonary disease. Standard median sternotomy (n = 27), lateral thoracotomy (n = 1) or minithoracotomy (n = 3) were performed for access and for harvesting the left internal mammary artery (LIMA). Measurements and results: The mean number of bypasses was 1.2 and 1.1 in groups A and B, respectively. Thirty patients received a LIMA graft to the left anterior descending artery (LAD). Homologous blood transfusions were needed in five patients (21%) in group A and four (50%) in group B. There were no wound infections or neurologic complications. All patients in group A survived and are asymptomatic. One patient in group B died of septic shock, two have residual angina pectoris or dyspnea, and five are asymptomatic. Conclusion: Coronary artery bypass using the Octopus heart stabilizing device proved to be a safe and effective technique resulting in complete revascularization in group A patients with no mortality. Incomplete revascularization may offer a substantial benefit to patients who cannot tolerate cardiopulmonary bypass due to poor general condition. We prefer median sternotomy, allowing precise harvesting of the internal mammary artery and more precise anastomoses without increased morbidity.

We report on a iatrogenic perioperative injury to the coronary sinus. Although oversewing venous bleeding sites on the heart usually resolves the problem, this caused an enormous venous engorgement of the posterior and apical regions of the heart, which prompted us to direct primary suture of the coronary sinus incision. A brief literature review with possible suggestions for solving this problem is given.