Long-term durability of aortic arch in situ stent graft fenestration requiring lifelong surveillance.

We report successful endovascular repair of a 61-year-old man treated for a 7.1-cm excentric aortic arch aneurysm by in situ stent graft fenestration for the brachiocephalic trunk and the left common carotid artery. Cerebral perfusion during the intervention was maintained by pump-driven extracorporal bypass to the right common carotid artery and to the left axillary artery provided with a left carotid-subclavian bypass. After 5 years of follow-up, the aortic arch in situ revascularization is still patent, the aneurysm excluded, and no endoleak detectable, although endovascular reintervention with distal aortic stent graft extension due to dilatation of the descending aorta was required.

Impact of age on early outcome after coronary bypass graft surgery using minimized versus conventional extracorporeal circulation.

BACKGROUND: Objective of this study was to evaluate the impact of age on comparative early outcomes after coronary artery bypass graft surgery (CABG) with minimized (MECC) and conventional extracorporeal circulation (CECC). METHODS: A retrospective age-, gender- and operation-matched cohort analysis between January 2005 and December 2010 with a total of 2274 patients undergoing CABG with MECC (n = 1137; 50%) or CECC was performed. Patients were stratified into 4 groups according to age: <59 years, 60-69 years, 70-79 years, and 80 years of age or older. Outcomes were compared within each age group. Patients with preoperative dialysis were excluded from analysis. Primary endpoint was 30-day mortality. RESULTS: Patients treated with CECC had a significantly higher mean logistic EuroSCORE (6.3% vs. 5.0%; p < 0.001), a slightly lower rate of preoperative myocardial infarction (46% vs. 51%; p = 0.01) and a higher rate of impaired renal function (eGFR < 60 mL/min/1.73 m2: 24% vs. 20%; p = 0.01) compared to MECC-patients. Left internal mammary artery was significantly used more often in MECC patients (93% vs. 86%; p < 0.001). Cardiopulmonary bypass and aortic-cross clamping time were significantly lower in the MECC group (p < 0.001). Overall 30-day mortality was significantly higher in patients treated with CECC (4.4% vs. 2.2%; p = 0.002). Within the different age groups mortality rates were not significantly different except for patients aged 60-69 years (4.5% vs. 1.8%; p = 0.03). Postoperative requirement of renal replacement therapy (4% vs. 2.2%; p = 0.01), respiratory insufficiency (9.9% vs. 6.6%; P = 0.004) and incidence of low cardiac output syndrome (3% vs. 1.2%; p = 0.003) were significantly increased in patients with CECC. Multivariate analysis identified age (p = 0.005; 95% CI 1.01 to 1.08; OR 1.05) among other parameters as an independent risk factor, whereas conventional extracorporeal circulation itself did not present as an independent risk factor for 30-day mortality. CONCLUSIONS: In this matched study sample early outcome was significantly better in patients with MECC compared to CECC, irrespective of age. Prior myocardial infarction estimated GFR < 60 mL and waiving the use of LIMA were independent risk factors for 30-day mortality, which were more present in the CECC group.

Emergency coronary artery bypass grafting using minimized versus standard extracorporeal circulation--a propensity score analysis.

BACKGROUND: The impact of minimized extracorporeal circulation (MECC) for emergency revascularization remains controversial. METHODS: A total of 348 patients underwent emergency CABG with MECC (n=146) or conventional extracorporeal circulation (CECC; n=175) between January 2005 and December 2010. Using propensity score matching after binary logistic regression, 100 patients, who underwent CABG with MECC could be matched with 100 patients, who underwent CABG with CECC. Primary outcome was 30-day mortality. RESULTS: Unadjusted 30-day mortality was 14.8% in patients with CECC and 6.9% in those with MECC (mean difference -7.9%; p=0.03). The adjusted mean difference (average treatment effect of the treated, ATT) after matching was -1.0% (95% CI -8.6 to 7.6; p=1.0). Intensive care unit stay (adjusted mean difference 1.0; 95% CI -0.2 to 3.2; p=0.70) and hospital stay (adjusted mean difference 1.0; 95% CI -2.0 to 3.6; p=0.40) did not show significant differences between both groups. The adjusted mean difference for postoperative low cardiac output syndrome was -1.1% (95% CI -7.3 to 7.1; p=0.83) without significant differences between CECC and MECC. Postoperative mechanical ventilation time, drain loss, postoperative rethoracotomy, postoperative neurological events, new onset renal replacement therapy and respiratory failure also had insignificant average treatment effects of the treated. In addition, all average treatment effects (ATEs) did not significantly differ between both groups. CONCLUSION: Using propensity score estimation and matching, we did not observe significant differences in terms of survival and further outcomes in patients who undergo emergency CABG with CECC or MECC, but our results call for further analysis.

Extracorporeal membrane oxygenation by single-vessel access in adults: advantages and limitations.

Veno-venous extracorporeal membrane oxygenation (vvECMO) conventionally requires the cannulation of two vessels. Here we report our initial experience with the "Wang-Zwische" (WZ) double-lumen cannula. In a group of n = 36 patients single venous cannulation for vvECMO was performed. A retrospective analysis was executed. A comparison of flow characteristics to standard two-vessel cannulation was performed. Mean age of the patient population was 48 ± 15 years (body mass index [BMI] 32 ± 13 kg/m(2)). In n = 32 patients (89%) the cannula was implanted percutaneously under echo or fluoroscopic guidance in less than 30 minutes. Nine patients were partially mobilized on extracorporeal membrane oxygenation (ECMO) support. Oxygenation (partial arterial oxygen tension [PaO(2)]/fraction of inspired oxygen [FiO(2)]) improved significantly in all patients from 66 mm Hg (interquartile range [IQR] 58-87 mm Hg) before ECMO to 117 mm Hg (IQR 95-195 mm Hg, p = 0.001) after 24 hours. In seven patients (19%) nonfatal adverse events occurred, including three dislocations, two partial cannula thrombosis, one ventricular perforation, and one retroperitoneal hemorrhage. The negative pressures for drainage at a flow of 2.5 L/min were significantly lower in a standard (S) two-vessel approach compared with a WZ approach (S: -9 mm Hg; IQR -3 to -24 mm Hg, vs. WZ: -23 mm Hg; IQR -4 to -40 mm Hg; p = 0.04). The WZ cannula offers sufficient gas exchange in addition to certain advantages over standard cannulation, including facilitated cannulation in selected patients and improved mobilization.

Successful coronary artery bypass grafting with the aid of a portable minimized extracorporeal life support system.

Extracorporeal life support system has been successfully used in patients with cardiac failure after open heart surgery, as a bridge to transplantation, and in patients with prolonged cardiogenic shock or cardiopulmonary arrest. This report presents our early experience with the new system Cardiohelp in coronary artery bypass grafting (CABG). Between August 2010 and June 2011, 50 patients underwent CABG with the aid of Cardiohelp. This subgroup was matched for sex and logistic EuroSCORE with 100 patients, who underwent CABG using two different extracorporeal circulation systems, a minimized (MECC) (n = 50) and a conventional (CECC) (n = 50) during the same period. Because of less hemodilution, the intraoperative blood transfusion was significantly lower in the Cardiohelp group (36%) and MECC group (40%) compared with the CECC group (64%). Postoperative release of creatinine kinase and lactate was lower in the Cardiohelp and MECC groups (p < 0.001). Furthermore, these patients had shorter duration of ventilation and lengths of stay at the intensive care unit (p < 0.05). Device-related complications were not observed. A conversion to CECC was not necessary. In conclusion, the Cardiohelp is a safe alternative for CABG surgery. Valid technical innovations and limited number of side effects support its employment as a highly effective device for coronary surgery.

Quality of life following surgery of ascending aorta and aortic arch with selective antegrade cerebral perfusion.

OBJECTIVE: Surgery of the ascending aorta and aortic arch has been challenging since its inception as neurological complications may occur significantly affecting the quality of life (QOL). METHODS: From January 1998 to December 2007, 79 patients mainly suffering aortic dissection (65%) or true aortic aneurysm (34%) underwent surgery on the aortic arch employing deep hypothermic circulatory arrest and selective antegrade cerebral perfusion. QOL was assessed with the sickness-impact-profile (SIP) comprising 136 questions and 12 categories. RESULTS: All patients underwent replacement of the ascending aorta, combined with a partial (hemiarch) (n = 33; 42%) or total (n = 46, 58%) arch replacement. Thirty-day mortality was 17.7% (n = 14 patients). Perioperatively, three patients (3.8%) suffered a transitory ischemic attack (TIA) and 5.1% patients suffered a stroke. The median score of the complete questionnaire was 4.7, which demonstrates excellent QOL following such complex surgical procedures. The median physical dimension was 2.5 (0; 8), the psychosocial median score was 3.7 (1.2; 16.1), both underline an only minimal impairment of the daily life. CONCLUSION: The QOL after following the surgery of ascending aorta and aortic arch with selective antegrade cerebral perfusion is excellent on the long-term as assessed by the SIP.

Reduced 30-day mortality in men after elective coronary artery bypass surgery with minimized extracorporeal circulation-a propensity score analysis.

BACKGROUND: Impact of minimized extracorporeal circulation (MECC) for coronary surgery on mortality remains controversial and gender significantly influence outcome. METHODS: We analyzed 3,139 male patients undergoing elective coronary surgery between 01/2004 and 05/2009. Using propensity score matching after binary logistic regression, 1,005 patients (from 1,119 patients) undergoing surgery with MECC could be matched with 1,005 patients (from 2,020 patients) undergoing surgery with conventional extracorporeal circulation (CECC). Primary outcome was 30-day mortality. RESULTS: Unadjusted 30-day mortality was 2.7% in patients with CECC and 0.8% in those with MECC (mean difference -1.9%; p < 0.001). The adjusted mean difference (average treatment effect of the treated) after matching was -1.5% (95% confidence interval (CI) -2.6 to -0.4; p = 0.006). Postoperative hospital stay was shorter in patients operated with minimized systems (adjusted mean difference -0.8 days; 95% CI -1.46 to -0.09; p = 0.03) and incidence of postoperative neurocognitive dysfunction was also lower (adjusted mean difference -1.3%; 95% CI -2.2 to -0.4; p = 0.001). Chest tube drainage (adjusted mean difference +22 mL; 95% CI -47 to 91; p = 0.5) and risk for acute kidney injury, kidney injury and failure according to RIFLE criteria (adjusted mean difference -1.0%; 95% CI -2.5 to 0.6; p = 0.24) proved to be insignificant between both groups. Apart from reduced 30-day mortality, however, average treatment effects for intensive care unit stay, postoperative hospital stay, chest tube drainage and kidney injury did not significantly differ. CONCLUSION: Using propensity score analysis, we observed an association between MECC and reduced 30-day mortality in men, but our results call for further analysis.

Gender's impact on outcome in coronary surgery with minimized extracorporeal circulation.

BACKGROUND: The role of female gender in cardiac surgery is still controversial. We examined the impact of gender on mortality after coronary artery bypass grafting (CABG) with minimized extracorporeal circulation (MECC). METHODS: Between January 2004 and May 2009, 1,662 patients (439 females, 1,223 males) underwent CABG with MECC at the University Medical Center Regensburg. Perioperative data were retrospectively analyzed; primary end point was in-hospital mortality. RESULTS: At operation, women were older, had a higher prevalence of diabetes and impaired renal function, and underwent more often non-elective surgery. Unadjusted mortality was significantly lower for men and than for women (2.3 vs. 5.7%; p = 0.001). Risk-adjusted mortality rates were derived by stepwise logistic regression. The final model reduced the gender-related mortality gap from 147 to 32%. Goodness of fit and discriminatory performance (AUC = 0.83) were good. Female gender, however, could not be identified as an independent risk factor for adverse outcome (OR 1.6; 95% CI 0.8-3.4). Risk-adjusted mortality was calculated as 4.9% in females and 2.6% in males. Low body surface area (<1.66 m(2)) was associated with excess mortality in females. CONCLUSIONS: Gender-related disparity in outcome still remains present after surgery with minimized extracorporeal circulation. However, female gender per se is not an independent risk factor for in-hospital mortality, but close attention should be paid on modifiable risk factors.

Temporary percutaneous right ventricular support using a centrifugal pump in patients with postoperative acute refractory right ventricular failure after left ventricular assist device implantation.

OBJECTIVE: Acute right ventricular (RV) failure is a life-threatening condition with a poor prognosis, and sometimes the use of mechanical circulatory support is inevitable. In this article, we describe our experience using a centrifugal pump as a temporary percutaneous right ventricular assist device (RVAD) in patients with postoperative acute refractory RV failure after left ventricular assist device (LVAD) implantation. METHODS: We retrospectively reviewed eight consecutive patients with acute RV failure who underwent temporary percutaneous RVAD implantation using a centrifugal pump after LVAD implantation between April 2008 and February 2011. A Dacron graft was attached to the main pulmonary artery and passed through a subxiphoid exit, where the outflow cannula was inserted. The inflow cannula was percutaneously cannulated using Seldinger's technique in the femoral vein. The chest was definitely closed. The technique allowed bedside removal, avoiding chest re-opening. RESULTS: The median patient age was 52 years (range: 41-58). The median duration of support was 14 days (range: 12-14). RV systolic function improved; central venous pressure and mean pulmonary artery pressure decreased significantly after RVAD support. In three patients, an oxygenator was integrated into the RVAD due to impaired pulmonary function. Six patients were successfully weaned. Five patients survived to hospital discharge. Technical problems or serious complications concerning decannulation were not observed. CONCLUSION: This report suggests that implantation of temporary percutaneous RVAD using a centrifugal pump is a safe alternative in the treatment of postoperative acute refractory RV failure. Ease of device implantation, weaning, explantation, and limited number of complications justify a liberal use.

Late reoperations after repaired acute type A aortic dissection.

OBJECTIVE: Late complications can develop in patients after surgery for aortic type A dissection, mandating redo surgery on the ascending aorta and arch. METHODS: From 2006 to 2010, 23 patients (aged 41-69 years) who had late complications related to previous aortic surgery for acute type A dissection underwent redo surgery. Initial surgery included ascending aorta replacement in all cases. RESULTS: The main indications for reoperation were progressive enlargement of the false lumen of the aortic arch or descending aorta and suture line dehiscence in 10 patients each. All patients with progressive aneurysm formation in nonresected aortic segments had persistent dissection within the aortic arch since initial surgery. Suture line dehiscence led to a localized hematoma in most cases. Three patients presented with graft infection and extensive perigraft hematoma. The average time interval from the initial repair to the redo procedure was 71±56 months. Exchange of the formerly implanted Dacron graft in the ascending aorta was the most frequently used surgical procedure. Implantation of a valved conduit was deemed necessary in 4 cases, and isolated aortic valve replacement was necessary in 2 cases. A hybrid stent graft was used in 6 patients. All patients survived surgery, and 1 patient died of postoperative low output cardiac failure in hospital. Only 1 major stroke was noted. CONCLUSIONS: Complex reoperations for repaired acute type A dissection can be performed safely. The concern for the reoperative risk should not dictate the operative strategy during the initial procedure in acute type A dissection.

Coronary artery bypass grafting in patients with type 2 diabetes mellitus: a comparison between minimized and conventional extracorporeal circulation.

Diabetes mellitus (DM) is an established independent risk factor for significant morbidity and mortality after coronary artery bypass grafting (CABG). The minimized extracorporeal circulation (MECC) allows a reduction of the negative effects associated with conventional extracorporeal circulation (CECC). In this study, the impact of the MECC on outcome of diabetic patients after CABG was assessed. Between January 2002 and December 2009, 1,184 patients with DM underwent elective isolated CABG using CECC (54.6%) or MECC (45.4%). All analysis was performed retrospectively. The extracorporeal circulation time was significantly reduced during MECC procedure. The postoperative increase of creatine kinase and lactate levels was significantly weaker in the MECC group (p < 0.001). Also, the transfusion requirements were significantly lower (p < 0.001). Furthermore, MECC patients had lower incidences of postoperative acute renal failure and sternal wound infections and shorter ICU and hospital lengths of stay (p < 0.05). Moreover, 30-day mortality was significantly reduced in the MECC group (p < 0.05). In conclusion, CABG surgery using MECC system is a safe alternative in patients with DM. A reduced postoperative mortality and lengths of stay, lower transfusion requirements, less renal and myocardial damage, and lower incidence of sternal wound infections encourage the usage of MECC system, especially in high-risk patients.

Successful use of hirudin during cardiac surgery using minimized extracorporeal circulation in patients with heparin-induced thrombocytopenia.

In this case series, we describe our successful use of a reduced hirudin dosage as an anticoagulant during cardiac surgery using minimized extracorporeal circulation in patients with heparin-induced thrombocytopenia.

Minimized extracorporeal circulation system in coronary artery bypass surgery: a 10-year single-center experience with 2243 patients.

OBJECTIVE: Coronary artery bypass grafting (CABG) is the gold standard for the surgical therapy of multivessel coronary artery disease. To reduce the side effects, associated with standard extracorporeal circulation (ECC), a concept of minimal extracorporeal circulation (MECC) was devised in our center. We report on our 10-year experience with the MECC for coronary revascularization. METHODS: From January 1998 to August 2009, 2243 patients underwent CABG with MECC in our center. In a retrospective observational study, we analyzed indication, preoperative patient co-morbidity, postoperative clinical course, and perioperative outcome of all patients operated on with MECC. Furthermore, the risk factors for mortality in the MECC group were assessed. RESULTS: Patients showed a mean logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) of 4.5±0.1%. The mean age of the patients was 66.8±9.1 years. The overall 30-day mortality after CABG with MECC was 2.3%, ranging from 1.1% for elective to 13.0% for emergent patients and was significantly better than standard ECC. Only 15.3% (n=344) of patients with MECC required intra-operative blood transfusion. Postoperative catecholamine support, red blood cell transfusion, need for hemodialysis, release of creatinine kinase, incidence of stroke, and postoperative delirium were low after MECC revascularization. Ejection fraction below 30% (odds ratio (OR): 5.1), emergent operation (OR: 9.4), and high-dose catecholamine therapy (OR: 2.6) were associated predictors for mortality. CONCLUSION: MECC until now is an established concept and has become an alternative for ECC in routine CABG in our center. The use of the MECC system is associated with low mortality and conversion rate. Excellent survival rates and low transfusion requirements in the perioperative course were achieved.

Diagnosis of unicommissural unicuspid aortic valve stenosis by different imaging modalities.

A 32-year-old woman was admitted to our institution for further evaluation of aortic stenosis. Diagnosis of severe aortic stenosis was made by transthoracic echocardiography. Transesophageal echocardiography, live three-dimensional echocardiography and cardiovascular MRI allowed precise evaluation of valve morphology. Interestingly, valve morphology was unicuspid unicommissural with a posterior funnel-shaped valve opening. Surgical inspection during valve replacement confirmed the diagnosis of an unicuspid aortic valve. This case report highlights the use of different imaging modalities in characterizing aortic valve morphology.

Variable phenotypes of bicuspid aortic valve disease: classification by cardiovascular magnetic resonance.

BACKGROUND: Recently, cardiovascular magnetic resonance (CMR) has been shown to allow accurate visualisation and quantification of aortic valve disease. Although bicuspid aortic valve (BAV) disease is relatively rare in the general population, the frequency is high in patients requiring valve surgery. The aim of the current study was to characterise the different phenotypes of BAV disease by CMR. METHODS: CMR studies were performed on a 1.5 T scanner in 105 patients with BAV. RESULTS: The pattern of BAV phenotypes was as follows: a raphe was identified in 90 patients (86%). Among patients with raphe, 76 patients had fusion between the right and left cusps (RL) and 14 patients had fusion between the right and the non-coronary cusps (RN). There were no significant differences in the aortic dimensions in the different BAV phenotypes. CONCLUSION: CMR allows excellent characterisation of valve phenotype in patients with BAV. The present data demonstrate that a raphe is present in the vast majority of cases and RL fusion is the predominant phenotype of BAV. No significant differences in the aortic dimensions were observed.

Myocardial protection in patients undergoing coronary artery bypass grafting surgery using minimized extracorporeal circulation in combination with volatile anesthetic.

The minimized extracorporeal circulation (ECC) is a safe alternative for coronary artery bypass grafting (CABG) and allows a reduction of the negative effects associated with conventional extracorporeal circulation. Experimental and clinical data indicate that the anesthetic regime might influence the ischemia-reperfusion injury in CABG surgery. The aim of our retrospective study was to investigate the cardioprotective effects of two different minimized ECC systems in combination with two different anesthetic concepts and to determine the impact on oxygen consumption during aortic cross-clamping (ACC). Data of 1,182 patients who underwent elective isolated CABG with minimized ECC from January 1, 2003, to December 31, 2008, were enrolled in a retrospective manner. Patients were allocated either to sevoflurane-based volatile anesthesia using PRECiSe system (SEVO group) or to propofol-based intravenous anesthesia using MECC system (PROP group). Postoperatively, the SEVO group showed lower concentrations of myocardial fraction of creatine kinase compared with the PROP group (p < 0.001). During the period of ACC, the values of systemic vascular resistance (SVR) were higher in SEVO group (p < 0.005). Also, the SEVO group showed lower oxygen consumption at each time point ACC (p < 0.0001). In conclusion, PRECiSe system using a microporous capillary oxygenator in combination with sevoflurane-based volatile anesthetic regimen seem to provide lower postoperative myocardial cell damage and to allow improved perfusion with higher SVRs and lower oxygen consumption during ACC.

Minimized extracorporeal circulation cannot prevent acute kidney injury but attenuates early renal dysfunction after coronary bypass grafting.

We studied the impact of minimized extracorporeal circulation (MECC) on acute kidney injury (AKI) after coronary bypass grafting. A retrospective, observational study with 1,685 patients with MECC and 3,046 patients with conventional bypass was done. Primary outcome was AKI defined as a decline > or = 50% in estimated glomerular filtration rate (eGFR) within 48 hours after surgery. Secondary outcome was temporary dialysis. MECC exerts beneficial hemodynamic effects but does not prevent AKI. Fewer patients developed a decline in eGFR <60 mL/min/1.73 m(2) (MECC) compared with conventional extracorporeal circulation (ECC) (30.7% versus 45.5%, p < 0.001). The incidence of eGFR decrease by > or = 50% did not differ (1.8% versus 2.7%, p = 0.20). Temporary dialysis was required in 61 patients with ECC (2%) and in 16 patients with MECC (0.9%, p < 0.001). A preoperative eGFR <60 mL/min/1.73 m(2) increased in both groups the risk for mortality compared with patients with an eGFR >60 mL/min/1.73 m(2) (ECC: odds ratio 3.6, 95% confidence interval 2.6-4.9; MECC: odds ratio 4.9, 95% confidence interval 2.8-8.6). MECC is renoprotective in the early postoperative period but cannot prevent AKI. An impaired preoperative eGFR increases the risk for mortality irrespective of the cardiopulmonary bypass system used.

Minimised versus conventional cardiopulmonary bypass: outcome of high-risk patients.

BACKGROUND: Coronary artery bypass grafting (CABG) with extracorporeal circulation (ECC) is the gold standard for surgical coronary re-vascularisation. Recently, minimised extracorporeal circulation system (MECC) has been postulated a safe and advantageous alternative for multi-vessel CABG. METHOD: Between January 2004 and December 2007, 244 high-risk patients (logistic EuroScore (ES)>10%) underwent CABG in our institution. ECC was used in 139 (57%) and MECC in 105 (43%) patients. Demographic data including age (MECC: 73.4+/-7.4 years; ECC: 73.3+/-6.4 years), ES (MECC: 19.2+/-9.8%; ECC: 21.4+/-11.9%), left-ventricular ejection fraction (MECC: 45.6+/-16.1%; ECC: 43.1+/-15.3%), diabetes mellitus (MECC: 14.3%; ECC: 15.1%) and COPD (MECC: 6.7%; ECC: 7.9%) did not differ between the two groups. Preoperative end-stage renal failure was an exclusion criterion. The clinical course and serological/haematological parameters in the ECC and MECC patients were compared in a retrospective manner. RESULTS: Although the numbers of distal anastomoses did not differ between the two groups (MECC: 3.0+/-0.9; ECC: 2.9+/-0.9), ECC time was significantly shorter in the MECC group (MECC: 96+/-33 min; ECC: 120+/-50 min, p<0.01). Creatinine kinase (CK) levels were significantly lower 6 h after surgery in the MECC group (MECC: 681+/-1505 U l(-1); ECC: 1086+/-1338 U l(-1), p<0.05) and the need of red blood cell transfusion was significantly less after MECC surgery (MECC: 3 [range: 1-6]; ECC: 5 [range: 2-9] p<0.05). Moreover, 30-day mortality was significantly lower in the MECC group as compared to the ECC group (MECC: 12.4%; ECC: 26.6, p<0.01). DISCUSSION: MECC is a safe alternative for CABG surgery. A lower 30-day mortality, lower transfusion requirements and less renal and myocardial damage encourage the use of MECC systems, especially in high-risk patients.