Mid-term outcomes of off-pump versus on-pump coronary artery bypass graft surgery; statistical challenges in comparison.

BACKGROUND: Despite several studies comparing off- and on-pump coronary artery bypass grafting (CABG), the effectiveness and outcomes of off-pump CABG still remain uncertain. METHODS: In this registry-based study, we assessed 8163 patients who underwent isolated CABG between 2014 and 2016. Propensity score matching (PSM), inverse probability of weighting (IPW) and covariate adjustment were performed to correct for and minimize selection bias. RESULTS: The overall mean age of the patients was 62 years, and 25.7% were women. Patients who underwent off-pump CABG had shorter length of hospitalization (p < 0.001), intubation time (p = 0.003) and length of ICU admission (p < 0.001). Off-pump CABG was associated with higher risk of 30-days mortality (OR: 1.7; 95% CI 1.09-2.65; p = 0.019) in unadjusted analysis. After covariate adjustment and matching (PSM and IPW), this difference was not statistically significant. After an average of 36.1 months follow-up, risk of MACCE and all-cause mortality didn't have significant differences in both surgical methods by adjusting with IPW (HR: 1.03; 95% CI 0.87-1.24; p = 0.714; HR: 0.91; 95% CI 0.73-1.14; p = 578, respectively). CONCLUSION: Off-pump and on-pump techniques have similar 30-day mortality (adjusted, PSM and IPW). Off-pump surgery is probably more cost-effective in short term; however, mid-term survival and MACCE trends in both surgical methods are comparable.

Surgeons' Preference for Off-Pump or On-Pump Coronary Artery Bypass Grafting Surgery.

BACKGROUND: Surgeon's preference is an important factor in clinical strategy for off-pump (OPCAB) or on-pump (ONCAB) coronary artery bypass graft (CABG) surgery. This study analyzed surgeons' understanding of and propensity for both techniques. METHODS: A survey was performed by self-reported questionnaire. Two sections were included: Q1 questionnaire investigated each surgeon's opinion on the indications of OPCAB and ONCAB; and Q2 questionnaire investigated each surgeon's choice of OPCAB or ONCAB in different clinical situations. RESULTS: The questionnaires were sent to 169 surgeons. In Q1, 71.2% of surgeons indicated that the degree of overlap between the indications of OPCAB and ONCAB is >70%; 55.1% believed that OPCAB had a wider scope of indications than ONCAB, and 35.3% believed that ONCAB had a wider scope of indications than OPCAB. In Q2, >70% of surgeons who responded chose OPCAB for patients with the following characteristics: high risk of stroke, renal dysfunction, pulmonary dysfunction, malignancy, clotting and coagulation disorders, or age ≥80 years. More than 57.5% of surgeons chose ONCAB for patients with poor target vessels or ventricular enlargement and dysfunction. For novice surgeons, 87.5% of surgeons chose ONCAB. CONCLUSION: Most surgeons surveyed agreed that OPCAB and ONCAB are suitable for most patients; however, surgeons' preference for ONCAB or OPCAB varied. Surgeons are more willing to choose ONCAB in the presence of complicated heart conditions and OPCAB in the presence of serious concomitant diseases.

Extracorporeal life support system during cardiovascular procedures: Insights from the German Lifebridge registry.

The frequency of mechanical circulatory support (MCS) device application has increased in recent years. Besides implantation in the emergency setting, such as circulatory arrest, MCS is also increasingly used electively to ensure hemodynamic stability in high-risk patients, for example, during percutaneous coronary interventions (PCI), valve interventions or off-pump coronary bypass surgery. Lifebridge (Zoll Medical GmbH, Germany) is a compact percutaneous MCS device widely used in daily clinical routine. The present study aimed to investigate the indications, feasibility, and outcomes after use of Lifebridge in cardiac interventions, evaluating a large-scale multicenter database. A total of 60 tertiary cardiovascular centers were questioned regarding application and short-term outcomes after the use of the Lifebridge system (n = 160 patients). Out of these 60 centers, eight consented to participate in the study (n = 39 patients), where detailed data were collected using standardized questionnaires. Demographic and clinical characteristics of the patient population, procedural as well as follow-up data were recorded and analyzed. In 60 interrogated centers, Lifebridge was used in 74% of emergency cases and 26% in the setting of planned interventions. The subcohort interrogated in detail displayed the same distribution of application scenarios, while the main cardiovascular procedure was high-risk PCI (82%). All patients were successfully weaned from the device and 92% (n = 36) of the patients studied in detail survived after 30 days. As assessed 30 days after insertion of the device, bleeding requiring red blood cell (RBC) transfusion constituted the main complication, occurring in 49% of cases. In our analysis of clinical data, the use of Lifebridge in cardiac intervention was shown to be feasible. Further prospective studies are warranted to identify patients who benefit from hemodynamic MCS support despite the increased rate of RBC transfusion due to challenges in access sites during cardiovascular procedures.

Hospital Variability Drives Inconsistency in Antiplatelet Use After Coronary Bypass.

BACKGROUND: Continuation of dual antiplatelet therapy (DAPT) after coronary artery bypass grafting (CABG) after acute myocardial infarction is recommended by current guidelines. We sought to evaluate guideline adherence over time and factors associated with postoperative DAPT within a regional consortium. METHODS: Isolated CABG patients from 2011 to 2017 who had a myocardial infarction within 21 days prior to surgery were included. Patients were stratified by DAPT prescription at discharge and by time period, early (2011-2014) vs late (2015-2017). Hierarchical regressions were then performed to evaluate factors influencing DAPT use after CABG. RESULTS: A total of 7314 patients were included with an overall rate of DAPT utilization of 31.2% that increased from 29.6% in the early to 33.4% in the late era (P < .01). There was considerable variability in hospital rates of DAPT (range 9.5%-92.1%) and hospital level changes over time (26% increased, 11% decreased, and 63% remained stable). After adjustment for clinical factors, era was not associated with DAPT use but treating hospital remained significantly associated with DAPT use. Other clinical factors associated with increased DAPT utilization included off-pump surgery (odds ratio [OR] 4.48, P < .01) and prior percutaneous coronary intervention (OR 2.02, P < .01), and atrial fibrillation (OR 0.39, P < .01) was associated with decreased utilization. CONCLUSIONS: Dual antiplatelet use has increased between 2011 and 2017, driven primarily by evolving patient demographics. Significant hospital-level variability drives inconsistency in DAPT utilization. Efforts to promote DAPT use for patients treated with CABG after myocardial infarction in concordance with current guidelines should be targeted at the hospital level.

Intraoperative transfusion and an increased preoperative C-reactive protein level are associated with higher mortality after off-pump coronary artery bypass grafting.

OBJECTIVE: The effects of transfusion on clinical outcomes after cardiac surgery remain inconclusive. We hypothesized that the risk of postoperative cumulative long-term, all-cause mortality after transfusion in patients undergoing cardiac surgery would differ by individual inflammatory status reflected by C-reactive protein level; thus, we performed a retrospective study. METHODS: All patients who underwent isolated off-pump coronary artery bypass grafting between October 2004 and October 2015 were retrospectively included. Patients were divided into 4 categories according to whether the preoperative C-reactive protein level was greater than or less than 1 mg/dL and whether red cells were transfused intraoperatively. The 4 categories were as follows: low C-reactive protein without transfusion; low C-reactive protein with transfusion; high C-reactive protein without transfusion; and high C-reactive protein with transfusion. A multivariable Cox regression was then performed. Sensitivity analysis in subgroup (<3 units of red cells transfused) was also performed. RESULTS: A total of 1636 patients were analyzed. Of the 4 categories, patients in the high C-reactive protein with transfusion group were at significantly higher risk of mortality than the low C-reactive protein without transfusion (hazard ratio, 1.86; 95% confidence interval, 1.24-2.79) or with transfusion group (hazard ratio, 1.47; 95% confidence interval, 1.13-1.93). A sensitivity analysis of patients who received only 1 or 2 units of red cells showed similar results. CONCLUSIONS: Intraoperative red blood cell transfusion in patients with increased C-reactive protein level was significantly related to the risk of mortality after off-pump coronary artery bypass grafting.

Early silent graft failure in off-pump coronary artery bypass grafting: a computed tomography analysis†.

OBJECTIVES: The purpose was to assess predictors of early silent graft failure prior to discharge by multislice computed tomography in patients after off-pump coronary artery bypass grafting. METHODS: From January 2017 until April 2018, 192 computed tomographic scans of consecutive asymptomatic patients were performed (seventh postoperative day ± 4 days) and analysed retrospectively. In total, 359 arterial and 278 venous anastomoses were evaluated. Two patient groups (overall patent anastomoses versus at least 1 occluded anastomosis) were compared. Cardiovascular risk factors, collateralization according to Rentrop, grade of native vessel stenosis and intraoperative flow measurements were analysed. Inferential statistics were performed with the Mann-Whitney U-test. Nominal and categorical variables were tested with the Fisher-Freeman-Halton exact test. RESULTS: In 33 patients, at least 1 occluded anastomosis could be identified, predominantly in women (P = 0.04). The patency of the arterial anastomoses was 96.4% and 88.9% for the venous anastomoses. In 14 patients with occluded anastomoses, a successful interventional revascularization was performed before discharge. There were significant differences in lower bypass flow [P = 0.02, odds ratio 3.2, 95% confidence interval (CI) 1.7-6.0] and higher pulsatility index (P < 0.001, odds ratio 4.5, 95% CI 2.4-8.5) in the occluded group. A calculated cut-off value identified an increased probability for graft occlusion at a flow under 23 ml/min and a pulsatility index greater than 2.3. CONCLUSIONS: Early silent graft failure occurred predominantly in venous grafts, with a tendency to female gender. A lower flow rate and a higher pulsatility index were significantly associated with graft occlusion, whereas collateralization and the degree of native vessel stenosis seem to play a tangential role. Fourteen patients had a successful percutaneous revascularization before discharge. CLINICAL TRIAL REGISTRATION NUMBER: NCT03657199.

Implementation of the aortic no-touch technique to reduce stroke after off-pump coronary surgery.

OBJECTIVES: Despite substantial scientific effort, the relationship between stroke after coronary artery bypass grafting and the use of the aortic no-touch off-pump technique (anOPCAB) remains incompletely understood. The present study aimed to define the effect of anOPCAB on the occurrence and time point of stroke. METHODS: A total cohort of 15,042 consecutive patients underwent surgical myocardial revascularization at a single institution. After establishing anOPCAB as routine procedure, 4695 patients received surgery by 18 different surgeons using the anaortic approach. After the exclusion of all patients with cardiogenic shock and "side-clamp" off-pump coronary artery bypass grafting, 13,279 patients (4485 with anOPCAB) were included in the study. Perioperative strokes were classified as strokes occurring during the hospital stay, with early strokes observed immediately after emergence from anesthesia (vs delayed strokes). RESULTS: The anOPCAB technique reduced the postoperative stroke rate to 0.49% versus 1.31% in on-pump patients (P < .0001). The overall stroke rate after adoption of anOPCAB (0.64%) decreased compared with before its adoption (1.40%; P < .0001). With anOPCAB, the risk of early strokes virtually disappeared to 4 of 4485 patients (0.09%; 95% confidence interval, 0.00-0.18% vs 0.83% in on-pump patients; P < .0001), whereas the incidence of delayed strokes was not affected (0.40% vs 0.48%; P = .5181). The key results were confirmed after adjustment using propensity score-based analyses. CONCLUSIONS: The anOPCAB technique with avoidance of any aortic manipulation is an effective tool to minimize the risk of early strokes during coronary artery bypass grafting, and thus, should be considered as a routine approach. In contrast, additional preventive strategies against delayed strokes remain to be elaborated.

Effect of the proximal anastomosis site on mid-term radial artery patency in off-pump coronary artery bypass.

OBJECTIVES: The purpose of this study was to evaluate mid-term patency and clinical outcomes according to the proximal anastomosis site after off-pump coronary artery bypass using the radial artery (RA). METHODS: From January 2001 to December 2015, 1124 patients who underwent isolated off-pump coronary artery bypass using the RA were reviewed and divided into 2 groups: the composite Y-graft (n = 1014, Y group) and aortocoronary graft (n = 110, Aorta group). Graft patency was assessed by computed tomography or coronary angiography. RESULTS: Patients receiving Y-grafts had a greater number of RA anastomoses (1.79 ± 0.68 per patient vs 1.40 ± 0.51 per patient, P < 0.001), more sequential grafts (55.6% vs 37.3%, P < 0.001) and a higher incidence of total arterial revascularization (77.9% vs 54.5%, P < 0.001). Postoperative graft patency at a mean of 3.1 ± 3.5 years was assessed in 1944 distal RA anastomoses (Y group: 1811, Aorta group: 133). No significant differences were observed in RA graft patency rate (P = 0.705), overall survival (P = 0.987) and major cardiac event-free survival (P = 0.830) between groups. Multivariable analysis demonstrated that the independent predictors of graft occlusion were age [hazard ratio (HR) 1.025, confidence interval (CI) 1.007-1.044; P = 0.007], female gender (HR 1.391, CI 1.007-1.924; P = 0.047), target of the right coronary artery territory (HR 2.135, CI 1.347-3.382; P = 0.001) and target vessel stenosis ≥90% (HR 0.478, CI 0.291-0.785; P = 0.004). The proximal anastomosis site was not significantly associated with graft occlusion (P = 0.705). CONCLUSIONS: When target vessel territory and stenosis are appropriately considered, the RA as a secondary conduit can be effectively used for myocardial revascularization, regardless of the proximal anastomosis site.

Beating-heart registration for organ-mounted robots.

BACKGROUND: Organ-mounted robots address the problem of beating-heart surgery by adhering to the heart, passively providing a platform that approaches zero relative motion. Because of the quasi-periodic deformation of the heart due to heartbeat and respiration, registration must address not only spatial registration but also temporal registration. METHODS: Motion data were collected in the porcine model in vivo (N = 6). Fourier series models of heart motion were developed. By comparing registrations generated using an iterative closest-point approach at different phases of respiration, the phase corresponding to minimum registration distance is identified. RESULTS: The spatiotemporal registration technique presented here reduces registration error by an average of 4.2 mm over the 6 trials, in comparison with a more simplistic static registration that merely averages out the physiological motion. CONCLUSIONS: An empirical metric for spatiotemporal registration of organ-mounted robots is defined and demonstrated using data from animal models in vivo.

An early European experience with transapical off-pump mitral valve repair with NeoChord implantation.

OBJECTIVES: Transapical off-pump NeoChord repair is a novel minimally invasive surgical procedure to treat degenerative mitral valve regurgitation. The aim was to evaluate 1-year clinical results of the NeoChord procedure in a consecutive cohort of patients. METHODS: Between February 2013 and July 2016, 213 patients were enrolled in the NeoChord Independent International Registry. All patients presented severe mitral regurgitation due to flail/prolapse of 1 or both leaflets, and they all completed postoperative echocardiographic assessment up to 1 year. We identified the primary end point as composed of procedural success, freedom from mortality, stroke, reintervention, recurrence of severe mitral regurgitation, rehospitalization and decrease of at least 1 New York Heart Association functional class at 1-year follow-up. We also compared outcomes according to the anatomical classification (Type A: isolated central posterior leaflet disease; Type B: posterior multisegment disease; Type C: anterior, bileaflet, paracommissural disease with/without leaflet/annular calcifications). RESULTS: The median age was 68 years (interquartile range 56-77), and the median EuroSCORE II was 1.05% (interquartile range 0.67-1.76). The number of Type A, B and C patients was 82 (38.5%), 98 (46%) and 33 (15.5%), respectively. Procedural success was achieved in 206 (96.7%) patients. At 1-year follow-up, overall survival was 98 ± 1%. Composite end point was achieved in 84 ± 2.5% for the overall population and 94 ± 2.6%, 82.6 ± 3.8% and 63.6 ± 8.4% in Type A, Type B and Type C patients, respectively (P < 0.0001). CONCLUSIONS: These results demonstrate that the NeoChord procedure is safe, effective and reproducible. Clinical and echocardiographic efficacy is maintained up to 1 year with significant differences among the anatomical groups. Specific anatomical selection criteria are necessary to achieve stable results.

Does Robotic Beating Heart Connector Totally Endoscopic Coronary Artery Bypass Bridge the Gender Gap in Coronary Bypass Surgery?

OBJECTIVE: Previous studies have shown that women carry a higher risk of morbidity and mortality after coronary artery bypass surgery. We investigated gender differences in risk factors and outcomes in our patients undergoing robotic beating heart connector totally endoscopic coronary artery bypass. METHODS: From July 2013 to April 2017, patients undergoing connector totally endoscopic coronary artery bypass were reviewed. We compared the outcomes of men versus women. RESULTS: A total of 192 men and 71 women underwent connector totally endoscopic coronary artery bypass. The mean ± SD age was 65.4 ± 10.6 years. The Society of Thoracic Surgeons score was higher in women than men (median = 1.46 vs 0.73, P = 0.001), and women had a higher rate of peripheral vascular disease (22.5% vs 9.9%, P = 0.007). Intraoperative data in women and men were similar except for the rate of multi-vessel connector totally endoscopic coronary artery bypass and the rate of bilateral internal mammary artery use, which were both lower in women (49.3% vs 64.6%, P = 0.024, and 42.3% vs 56.8%, P = 0.036, respectively). The mean ± SD length of hospital stay (women vs men: 3.99 ± 4.00 vs 3.39 ± 2.42, P = 0.324) was comparable. The 30-day mortality in women and men was 0% (0/71) and 2.1% (4/192), respectively (P = 0.577). The morbidity and mortality of single- or multi-vessel connector totally endoscopic coronary artery bypass were similar between men and women. CONCLUSIONS: We conclude that the morbidity and mortality in women after robotic beating heart connector totally endoscopic coronary artery bypass in our center were similar to those seen in men.

Conversion From Off-Pump Coronary Artery Bypass Grafting to On-Pump Coronary Artery Bypass Grafting.

BACKGROUND: Off-pump coronary artery bypass grafting (OPCAB) has been shown to be an effective strategy for surgical revascularization. The purpose of this study was to define the incidence of intraoperative conversion from OPCAB to on-pump coronary artery bypass grafting (ONCAB) and report outcomes based on the reason for conversion. METHODS: Starting in July 2007, the Society of Thoracic Surgeons database captured patients that were planned OPCAB but then were converted to ONCAB. A total of 196,576 patients undergoing planned OPCAB within the Society of Thoracic Surgeons National Database from July 2007 to June 2014 were evaluated. Patients were grouped according to their intraoperative conversion to cardiopulmonary bypass: (1) planned conversion, (2) unplanned conversion for visualization, (3) unplanned conversion for hemodynamic instability, and (4) no conversion (OPCAB). Multiple logistic regression analysis was used to determine risk factors for conversion. RESULTS: The overall rate of conversion from OPCAB to ONCAB was 5.5%, with 49.6% of the conversions being planned. When compared with those not undergoing conversion (OPCAB, 30-day mortality observed to expected ratio [O/E], 0.8), those undergoing conversion to ONCAB experienced greater 30-day mortality regardless of etiology of conversion (planned conversion O/E, 1.4; unplanned conversion for visualization O/E, 1.6; and unplanned conversion for hemodynamic instability O/E, 2.7). Similar O/E ratios were observed for renal failure and prolonged ventilation following conversion. Logistic regression analysis showed advanced age, ejection fraction less than 35%, preoperative intraaortic balloon pump placement, increasing number of diseased coronary arteries, preoperative heart failure within 2 weeks, and urgent procedural status were all independent predictors for conversion to ONCAB (p ≤ 0.01). CONCLUSIONS: Intraoperative conversion from OPCAB to ONCAB remains a morbid event with a risk of mortality much higher than expected. Surgeons should consider elective ONCAB in those with a high risk for conversion during OPCAB.

Abordagem PK-PD do propofol na revascularização do miocárdio para estudo da influência da circulação extracorpórea na ligação às proteínas plasmáticas e no efeito hipnótico / PK-PD Model to investigate the free propofol plasma levels versus the hypnotic drug effect in patients undergoing coronary artery bypass grafting concerning the influence of CPB-hypothermia on drug plasma binding

Durante a cirurgia de revascularização do miocárdio com circulação extracorpórea e hipotermia (CEC-H) ocorre alteração na efetividade do propofol e na sua farmacocinética realizada a partir das concentrações plasmáticas do propofol total no decurso do tempo. A ligação do propofol à proteína plasmática parece estar alterada em consequência de diversos fatores incluindo a hemodiluição e a heparinização que ocorre no início da circulação extracorpórea, uma vez que se reportou anteriormente que a concentração plasmática do propofol livre aumentou durante a realização da circulação extracorpórea normotérmica. Por outro lado, a infusão alvo controlada é recomendada para manter a concentração plasmática do propofol equivalente ao alvo de 2 µg/mL durante a intervenção cirúrgica com CEC-H. Se alterações significativas na hipnose do propofol ocorrem nesses pacientes, então o efeito aumentado desse agente hipnótico poderia estar relacionado à redução na extensão da ligação do fármaco as proteínas plasmáticas; entretanto, o assunto ainda permanece em discussão e necessita de investigações adicionais. Assim, o objetivo do estudo foi investigar as concentrações plasmáticas de propofol livre em pacientes durante a revascularização do miocárdio com e sem o procedimento de CEC-H através da abordagem PK-PD. Dezenove pacientes foram alocados e estratificados para realização de cirurgia de revascularização do miocárdio com circulação extracorpórea (CEC-H, n=10) ou sem circulação extracorpórea (NCEC, n=9). Os pacientes foram anestesiados com sufentanil e propofol alvo de 2 µg/mL. Realizou-se coleta seriada de sangue para estudo farmacocinético e o efeito foi monitorado através do índice bispectral (BIS) para medida da profundidade da hipnose no período desde a indução da anestesia até 12 horas após o término da infusão de propofol, em intervalos de tempo pré-determinados no protocolo de estudo. As concentrações plasmáticas foram determinadas através de método bioanalítico pela técnica de cromatografia líquida de alta eficiência. A farmacocinética foi investigada a partir da aplicação do modelo aberto de dois compartimentos, PK Solutions v. 2. A análise PK-PD foi realizada no Graph Pad Prisma v.5.0 após a escolha do modelo do efeito máximo (EMAX sigmóide, slope variável). Os dados foram analisados utilizando o Prisma v. 5.0, p<0,05, significância estatística. As concentrações plasmáticas de propofol total foram comparáveis nos dois grupos (CEC-H e NCEC); entretanto o grupo CEC-H evidenciou aumento na concentração do propofol livre de 2 a 5 vezes em função da redução na ligação do fármaco às proteínas plasmáticas. A farmacocinética do propofol livre mostrou diferença significativa entre os grupos no processo de distribuição pelo prolongamento da meia vida e aumento do volume aparente, e no processo de eliminação em função do aumento na depuração plasmática e redução na meia vida biológica no grupo CEC-H. A escolha do modelo EMAX sigmóide, slope variável foi adequada uma vez que se evidenciou alta correlação entre os valores do índice bispectral e as concentrações plasmáticas do propofol livre (r2>0.90, P<0.001) para os pacientes investigados

During coronary artery bypass grafting (CABG) surgery with cardiopulmonary bypass (CPB) profound changes occur on propofol effect and on kinetic disposition related to total drug plasma measurements in these patients. It was reported that drug plasma binding could be altered as a consequence of hemodilution and heparinization before starts CPB since free propofol plasma levels was increased by twice under normothermic procedure. In addition, the target controlled infusion (TCI) is recommended to maintain propofol plasma concentration (2 µg/mL) during CABG CPB-H intervention. However, whether significant changes that occur in propofol hypnosis in these patients could be related to the reduction on the extension of drug plasma binding remain unclear and under discussion until now. Then, the objective of this study was to investigate propofol free plasma levels in patients undergoing CABG with and without CPB by a pharmacokinetics-pharmacodynamics (PK-PD) approach. Nineteen patients were scheduled for on-pump coronary artery bypass grafting (CABG-CPB, n=10) or off-pump coronary artery bypass grafting (OPCABG, n=9) were anesthetized with sufentanil and propofol TCI (2 µg/mL). Blood samples were collected for drug plasma measurements and BIS were applied to access the depth of hypnosis from the induction of anesthesia up to 12 hours after the end of propofol infusion, at predetermined intervals. Plasma drug concentrations were measured using high-performance liquid chromatography, followed by a propofol pharmacokinetic analysis based on two compartment open model, PK Solutions v.2; PK-PD analysis was performed by applying EMAX model, sigmoid shape-variable slope and data were analyzed using Prisma v. 5.0, considering p<0.05 as significant difference between groups. The total propofol plasma concentrations were comparable in both groups during CABG; however it was shown in CPB-group significant increases in propofol free plasma concentration by twice to fivefold occur as a consequence of drug plasma protein binding reduced in these patients. Pharmacokinetics of free propofol in CPB-H group compared to OPCAB group based on two compartment open model was significantly different by the prolongation of distribution half-life, increases on plasma clearance, and biological half-life shortened. In addition, the kinetic disposition of propofol changes in a different manner considering free drug levels in the CPB-H group against OPCAB group as follows: prolongation of distribution half-life and increases on volume of distribution, remaining unchanged biological half-life in spite of plasma clearance increased. BIS values showed a strong correlation with free drug levels (r2>0.90, P<0.001) in CPB-H group and also in OPCAB group by the chosen EMAX model sigmoid shape-variable slope analyzed by GraphPad Prisma v.5.0

Preoperative factors affecting cost and length of stay for isolated off-pump coronary artery bypass grafting: hierarchical linear model analysis.

OBJECTIVE: To determine the effect of preoperative patient and hospital factors on resource use, cost and length of stay (LOS) among patients undergoing off-pump coronary artery bypass grafting (OPCAB). DESIGN: Observational retrospective study. SETTINGS: Data from the Japanese Administrative Database. PARTICIPANTS: Patients who underwent isolated, elective OPCAB between April 2011 and March 2012. PRIMARY OUTCOME MEASURES: The primary outcomes of this study were inpatient cost and LOS associated with OPCAB. A two-level hierarchical linear model was used to examine the effects of patient and hospital characteristics on inpatient costs and LOS. The independent variables were patient and hospital factors. RESULTS: We identified 2491 patients who underwent OPCAB at 268 hospitals. The mean cost of OPCAB was $40 665 ±7774, and the mean LOS was 23.4±8.2 days. The study found that select patient factors and certain comorbidities were associated with a high cost and long LOS. A high hospital OPCAB volume was associated with a low cost (-6.6%; p=0.024) as well as a short LOS (-17.6%, p<0.001). CONCLUSIONS: The hospital OPCAB volume is associated with efficient resource use. The findings of the present study indicate the need to focus on hospital elective OPCAB volume in Japan in order to improve cost and LOS.

The relationship between cardiotrophin-1 and troponin-i in coronary arterial bypass grafting on the beating heart: a prospective study.

OBJECTIVE: Cardiotrophin-1 (CT-1) is closely associated with many cardiovascular diseases, such as hypertension, myocardial infarction (MI), and heart failure, and exhibits a cardioprotective effect in ischemia-reperfusion injury. The aim of this study was to evaluate the relationship between CT-1 and Troponin-I (Tn-I) in off-pump coronary artery bypass (OPCAB) grafting on the beating heart. METHODS: Seventy-eight patients (mean age 60.8 ± 9.7 years, 79.5% male) undergoing elective OPCAB surgery were included in this study undertaken between July 1, 2012 and July 1, 2013 in the Department of Cardiology and Cardiac Surgery, University School of Medicine Hospital. Venous blood samples were collected 5 minutes before OPCAB surgery and 6 hours after surgery. Plasma CT-1 levels were measured using the ELISA method. RESULTS: Compared to the preoperative period, Tn-I and CT-1 values were higher in the postoperative period [0.255 ng/mL (0.030-0.430) versus 0.045 ng/mL (0.005-0.090), P < .001; and 33.7 pg/mL (15.8-98.5) versus 8.7 pg/mL (0.68-25.4), P < .001]. There was also an elevation in white blood cells, aspartate aminotransferase, creatine kinase (CK), and creatine kinase MB (CK-MB) values, as well as a decrease in hemoglobin values (P < .001). When a correlation analysis for postoperative CT-1 was performed, there was a significant positive correlation between postoperative CK, CK-MB, and Tn-I levels (r = 0.250, P < .027; r = 0.270, P = .017; and r = 0.241, P < .034). CONCLUSION: CT-1 was found to be associated with Tn-I, which is used to detect myocardial damage after OPCAB surgery. CT-1 may also be used to detect myocardial damage.

Risk Stratification in Off-Pump Coronary Artery Bypass (OPCAB) Surgery­Role of EuroSCORE II.

OBJECTIVES: To evaluate the EuroSCORE II for risk stratification in patients undergoing off-pump coronary artery bypass (OPCAB) surgery. DESIGN: A retrospective observational study. SETTING: Two tertiary care hospitals. PARTICIPANTS: Participants were 1,211 patients undergoing OPCAB surgery. INTERVENTIONS: No interventions were implemented. MEASUREMENTS AND MAIN RESULTS: The EuroSCORE II estimated the operative risk for each patient. The calibration of the scoring system was assessed using the Hosmer Lemeshow test, and the discriminative capacity was estimated with area under receiver operating characteristic curves. The incidence, patient characteristics, causes of intraoperative conversion to on-pump coronary artery bypass (ONCAB), and outcome were studied. The all-cause in-hospital mortality was 2.39%. Predicted mortality with the EuroSCORE II was 2.03±1.63. Using the Hosmer Lemeshow test, a C statistic of 8.066 (p = 0.472) was obtained, indicating satisfactory model fit. The calculated area under the receiver operating characteristic curve was 0.706 (p = 0.0002), indicating good discriminatory power. Emergency intraoperative conversion to ONCAB occurred in 6.53% of patients. The mortality in the ONCAB group was significantly higher compared with patients who underwent successful OPCAB surgery (15.18% v 1.5%, p<0.0001). On multiple regression analysis with conversion to ONCAB as the endpoint, associated factors were patients with a higher EuroSCORE II (odds ratio = 1.13, confidence interval = 1.03-1.27) and more-than-trivial mitral regurgitation (odds ratio = 1.84, confidence interval = 1.07-3.06). Net reclassification improvement of 0.714 (p<0.0001) was obtained when on-pump conversion was added to the EuroSCORE II. CONCLUSIONS: The EuroSCORE II has satisfactory calibration and discrimination power to predict mortality after OPCAB surgery. Intraoperative conversion to ONCAB is a major complication of OPCAB surgery. A higher EuroSCORE II also predicts higher probability of conversion to ONCAB.

Outcome of emergency coronary artery bypass grafting.

OBJECTIVES: The aim of this study was to evaluate the immediate and late outcome of emergency coronary artery bypass grafting (CABG) in a multicenter setting. DESIGN: Multicenter, retrospective study. SETTING: Four university hospitals. PARTICIPANTS: 596 patients were included in this study. INTERVENTIONS: Included patients underwent isolated, emergency CABG. MEASUREMENTS AND MAIN RESULTS: Sixty patients (absolute rate: 10.1%, pooled rate: 8.7%) died during the in-hospital stay period. Increasing emergency CABG classes (p<0.0001), recent myocardial infarction (p=0.019), left ventricular ejection fraction≤30% (p=0.034), on-pump surgery (p=0.012), and participating centers (p<0.0001) were independent predictors of in-hospital mortality. Survival rates at 1, 3, and 5 years were 86.4%, 81.6%, and 76.1%, respectively. Extracorporeal membrane oxygenation was used in 6 patients and 3 of them (50.0%) survived the immediate postoperative period. Patient populations of participating centers differed significantly in most of baseline characteristics. The preoperative use of intra-aortic balloon pump (8% to 51%) and off-pump surgery (2.8% to 56.3%) varied significantly between institutions. In-hospital mortality (2.8%, 5.9%, 7.7% and 19.8%, p<0.0001), as well as midterm survival, significantly differed between institutions (at 3 years, 90.6%, 89.8%, 81.2%, and 67.2%, p<0.0001). CONCLUSIONS: The outcome after emergency CABG is satisfactory despite a significant operative risk. However, the results of emergency CABG significantly differed between the participating institutions, likely due to differences in the referral pathways and perioperative treatment strategies. Evaluation of these factors is crucial for implementation of treatment in centers with suboptimal results.

The off-pump technique in redo coronary artery bypass grafting reduces mortality and major morbidities: propensity score analysis of data from the Japan Cardiovascular Surgery Database†.

OBJECTIVES: The benefits of off-pump coronary artery grafting (OPCAB) have been demonstrated. Especially in patients with a high number of comorbidities, redo coronary artery bypass grafting (CABG) remains a difficult entity of CABG, because patients are likely to have multiple risk factors and often have diseased patent grafts with adhesions. The aim of the present study was to evaluate the effects of the OPCAB technique in redo CABG on mortality and morbidity using data from the Japan Cardiovascular Surgery Database (JCVSD). METHODS: We analysed 34 980 patients who underwent isolated CABG between 2008 and 2011, as reported in the JCVSD. Of these, 1.8% of patients (n = 617/34980) had undergone redo CABG, including those who underwent OPCAB (n = 364; 69%) and on-pump CABG (n = 253; 41%). We used propensity score (PS) matching with 13 preoperative risk factors to adjust for differences in baseline characteristics between the redo OPCAB and on-pump redo CABG groups. By one-to-one PS matching, we selected 200 pairs from each group. RESULTS: There were no significant differences in patient background between the redo OPCAB and on-pump redo CABG groups after PS matching. There was no significant difference in the mean number of distal anastomoses after matching (2.41 ± 1.00 vs 2.21 ± 1.04, P = 0.074); nevertheless, the mean operation time was significantly shorter in the redo OPCAB than the on-pump redo CABG group (353.7 vs 441.3 min, P < 0.00010). Patients in the redo OPCAB group had a lower 30-day mortality rate (3.5 vs 7.0%, P = 0.18), a significantly lower rate of composite mortality or major morbidities (11.0 vs 21.5%, P = 0.0060), a significantly lower rate of prolonged ventilation (>24 h) (7.0 vs 15.0%, P = 0.016), a significantly shorter duration of intensive care unit (ICU) stay (ICU stay ≥ 8 days) (7.0 vs 14.5%, P = 0.023) and a significantly decreased need for blood transfusions (71.5 vs 94.0%, P < 0.00010) than patients in the on-pump redo CABG group. CONCLUSION: The off-pump technique reduced early operative mortality and the incidences of major complications in redo CABG.

On-pump versus off-pump coronary artery bypass surgery in high-risk patients.

This study aimed to evaluate on-pump versus off-pump coronary artery bypass grafting (CABG) in patients with a high-risk operative profile.The pre-, intra- and post-operative data of high-risk patients with additive European system for cardiac operative risk evaluation (additive Euro-SCORE) over 6 undergoing isolated CABG from January 2008 to December 2011 in this center were investigated and retrospectively analyzed. Using the propensity score-matching method, those patients with similar pre- and intra-operative characteristics were selected and their early clinical outcomes were compared.From January 2008 to December 2011, 485 consecutive patients (398 males, with a mean age of 70.9 ± 9.0 years) whose additive Euro-SCORE was over 6 were entered into this study. Off-pump coronary bypass grafting (OPCAB) was performed in 58.1% (n = 282), and the remaining patients underwent conventional coronary artery bypass grafting (CCABG). After propensity score matching, the two groups of patients (90 OPCAB patients versus 90 CCABG patients) were similar with regard to pre- and intra-operative characteristics but not duration of surgical procedure. No significant differences in hospital mortality were found. Compared to CCABG, high-risk patients undergoing OPCAB had significantly lower prevalence of postoperative respiratory failure and postoperative renal failure (6.7% versus 17.8%, P = 0.0386, 5.6% versus 16.7%, P = 0.0307, respectively). Through multivariate logistic regression analysis, type of procedure (CCABG versus OPCAB), as an independent risk factor, had an impact on the postoperative respiratory failure (OR = 2.36, 95%CI 1.44-4.97, P = 0.0312) and postoperative renal failure (OR = 2.86, 95%CI 1.61-5.81, P = 0.0037).Compared with CCABG, OPCAB reduced postoperative respiratory and renal morbidity in high-risk patients.