Coronary surgery in Europe: comparison of the national subsets of the European system for cardiac operative risk evaluation database

Use and safety of aprotinin in routine clinical practice: A European postauthorisation safety study conducted in patients undergoing cardiac surgery

BACKGROUND

Aprotinin has been used to reduce blood loss and blood product transfusions in patients at high risk of major blood loss during cardiac surgery. Approval by the European Medicines Agency (EMA) for its current indication is limited to patients at high risk of major blood loss undergoing isolated coronary artery bypass graft surgery (iCABG).

OBJECTIVE

To report current real-world data on the use and certain endpoints related to the safety of aprotinin in adult patients.

DESIGN

The Nordic aprotinin patient registry (NAPaR) received data from 83 European centres in a noninterventional, postauthorisation safety study (PASS) performed at the request of the EMA.

SETTING

Cardiac surgical centres committed to enrolling patients in the NAPaR.

PATIENTS

Patients receiving aprotinin agreeing to participate.

INTERVENTION

The decision to administer aprotinin was made by the treating physicians.

MAIN OUTCOME MEASURES

Aprotinin safety endpoints were in-hospital death, thrombo-embolic events (TEEs), specifically stroke, renal impairment, re-exploration for bleeding/tamponade.

RESULTS

From 2016 to 2020, 5309 patients (male 71.5%; >75 years 18.9%) were treated with aprotinin; 1363 (25.7%) underwent iCABG and 3946 (74.3%) another procedure, including a surgical treatment for aortic dissection ( n  = 660, 16.7%); 54.5% of patients received the full-dose regimen. In-hospital mortality in iCABG patients was 1.3% (95% CI, 0.66 to 1.84%) vs. 8.3% (7.21 to 8.91%) in non-iCABG patients; incidence of TEEs and postoperative rise in creatinine level greater than 44 μmol l -1 2.3% (1.48 to 3.07%) and 2.7% (1.79 to 3.49%) vs. 7.2% (6.20 to 7.79%) and 15.5% (13.84 to 16.06%); patients undergoing re-exploration for bleeding 1.4% (0.71 to 1.93%) vs. 3.0% (2.39 to 3.44%). Twelve cases of hypersensitivity/anaphylactic reaction (0.2%) were reported as Adverse Drug Reactions.

CONCLUSION

The data in the NApaR indicated that in this patient population, at high risk of death or blood loss undergoing cardiac surgery, including complex cardiac surgeries other than iCABG, the incidence of adverse events is in line with data from current literature, where aprotinin was not used.

TRIAL REGISTRATION

EU PAS register number: EUPAS11384.

Validation for EuroSCORE II in the Indonesian cardiac surgical population: a retrospective, multicenter study

BACKGROUND

In 2011, the European System for Cardiac Operative Risk (EuroSCORE) II was created as an improvement of the additive/logistic EuroSCORE for the prediction of mortality after cardiac surgery.

OBJECTIVE

To validate EuroSCORE II in predicting the mortality of open cardiac surgery patients in Indonesia.

METHODS

We performed a multi-center retrospective study of cardiac surgery patients from three participating centers (Dr. Sardjito Hospital, Kariadi Hospital, and Abdul Wahab Sjahranie Hospital) between January 1st, 2016, and December 31st, 2020. Discrimination and calibration tests were performed.

RESULTS

The observed mortality rate was 9.5% (73 out of 767 patients). The median EuroSCORE II value was 1.13%. The area under the curve for EuroSCORE II was 0.71 (95% CI: 0.65-0.77), suggesting fair discriminatory power. Calibration analysis suggested that EuroSCORE II underestimated postoperative mortality. Gender, age, chronic pulmonary disease, limited mobility, NYHA, and critical pre-operative state were significant predictors of post-cardiac surgery mortality in our population.

CONCLUSION

This study suggested that the EuroSCORE II was a poor predictor for postoperative mortality in Indonesian patients who underwent cardiac surgery procedures. Therefore, EuroSCORE II may not be suitable for mortality risk prediction in Indonesian populations, and surgical planning should be decided on an individual basis.

Patient and hospital factors associated with 30-day readmissions after coronary artery bypass graft (CABG) surgery: a systematic review and meta-analysis

BACKGROUND

Readmission after coronary artery bypass graft (CABG) surgery is associated with adverse outcomes and significant healthcare costs, and 30-day readmission rate is considered as a key indicator of the quality of care. This study aims to: quantify rates of readmission within 30 days of CABG surgery; explore the causes of readmissions; and investigate how patient- and hospital-level factors influence readmission.

METHODS

We conducted systematic searches (until June 2020) of PubMed and Embase databases to retrieve observational studies that investigated readmission after CABG. Random effect meta-analysis was used to estimate rates and predictors of 30-day post-CABG readmission.

RESULTS

In total, 53 studies meeting inclusion criteria were identified, including 8,937,457 CABG patients. The pooled 30-day readmission rate was 12.9% (95% CI: 11.3-14.4%). The most frequently reported underlying causes of 30-day readmissions were infection and sepsis (range: 6.9-28.6%), cardiac arrythmia (4.5-26.7%), congestive heart failure (5.8-15.7%), respiratory complications (1-20%) and pleural effusion (0.4-22.5%). Individual factors including age (OR per 10-year increase 1.12 [95% CI: 1.04-1.20]), female sex (OR 1.29 [1.25-1.34]), non-White race (OR 1.15 [1.10-1.21]), not having private insurance (OR 1.39 [1.27-1.51]) and various comorbidities were strongly associated with 30-day readmission rates, whereas associations with hospital factors including hospital CABG volume, surgeon CABG volume, hospital size, hospital quality and teaching status were inconsistent.

CONCLUSIONS

Nearly 1 in 8 CABG patients are readmitted within 30 days and the majority of these are readmitted for noncardiac causes. Readmission rates are strongly influenced by patients' demographic and clinical characteristics, but not by broadly defined hospital characteristics.

Diabetics have Inferior Long-Term Survival and Quality of Life after CABG

A prevalence of diabetes is increasing among the patients undergoing coronary artery bypass grafting (CABG). Data on whether health-related quality of life improves similarly after CABG in diabetics and nondiabetics are limited. We assessed long-term mortality and changes in quality of life (RAND-36 Health Survey) after CABG. Seventy-four of the 508 patients (14.6%) operated on in a single institution had a history of diabetes and were compared with nondiabetics. The RAND-36 Health Survey was used as an indicator of quality of life. Assessments were made preoperatively and repeated 1 and 12 years later. Thirty-day mortality was 2.7 versus 1.6 ( p  = 0.511) in the diabetics and nondiabetics. One- and 10-year survival rates in the diabetics and nondiabetics were 94.6% versus 97.0% ( p  = 0.287) and 63.5% versus 81.6% ( p  < 0.001), respectively. After 1 year, diabetics improved significantly ( p  < 0.005) in seven, and nondiabetics ( p  < 0.001) in all eight RAND-36 dimensions. Despite an ongoing decline in quality of life over the 12-year follow-up, an improvement was maintained in four out of eight dimensions among diabetics and in seven dimensions among nondiabetics. Physical and mental component summary scores on the RAND-36 improved significantly ( p  < 0.001) in both groups after 1 year, and at least slight improvement was maintained during the 12-year follow-up time. Diabetics have inferior long-term survival after CABG as compared with nondiabetics. They gain similar improvement of quality of life in 1 year after surgery, but they have a stronger decline tendency over the years.

AGE PECULIARITIES OF COMORBID PATHOLOGY IN PATIENTS UNDERGOING PLANNED CORONARY ARTERYBYPASS GRAFTING

Background: The number of elderly patients undergoing coronary artery bypass grafting (CABG) is increasing worldwide. Therefore, the assessment of comorbidities based on the age factor in patients with coronary artery disease (CAD) is highly relevant.Aim: To assess the associations between the age factor and comorbidities in patients undergoing CABG. Material and Methods: Data of 680 patients [538 (79.10%) men and 142 (20.90%) women], undergoing elective CABG in the period 2011-2012, included in the CABG Registry were used to detect comorbidities.All patients were enrolled into 4 age groups: below 50 years, 51-60 years, 61-70 years, over 70 years.Results: Aging was associated with an increase in the proportion of women suffering from arterial hypertension (AH), and multivessel disease. Similarly, the proportion of patients with higher func-tional class (FC) of angina, heart failure (CH), and heart rhythm disturbances increased. The number of patients referred to elective CABG with previous myocardial infarction (MI) was the highest among young adults (77%). Aging was associated with an increase in the number of patients with chronic pyelonephritis (44.30%) and thyroid pathology (3.40%).Conclusion: Patients’ aging is associated with an increase in cardiovascular comorbidities, but not MI. Importantly, there was no any increase in the rate of non-cardiovascular comorbidities.

Assessment of the EuroSCORE risk scoring system for patients undergoing coronary artery bypass graft surgery in a group of Iranian patients

Background and Aims:

Previous studies around the world indicated validity and accuracy of European System for Cardiac Operative Risk Evaluation (EuroSCORE) risk scoring system we evaluated the EuroSCORE risk scoring system for patients undergoing coronary artery bypass graft (CABG) surgery in a group of Iranian patients.

Materials and Methods:

In this cohort 2220 patients more than 18 years, who were performed CABG surgery in Massih Daneshvari Hospital, from January 2004 to March 2010 were recruited. Predicted mortality risk scores were calculated using logistic EuroSCORE and Acute Physiology and Chronic Health Evaluation II (APACHE II) and compared with observed mortality. Calibration was measured by the Hosmer–Lemeshow (HL) test and discrimination by using the receiver operating characteristic (ROC) curve area.

Results:

Of the 2220 patients, in hospital deaths occurred in 270 patients (mortality rate of 12.2%). The accuracy of mortality prediction in the logistic EuroSCORE and APACHE II model was 89.1%; in the local EuroSCORE (logistic) was 91.89%; and in the local EuroSCORE support vector machines (SVM) was 98.6%. The area under curve for ROC curve, was 0.724 (95% confidence interval [CI]: 0.57–0.88) for logistic EuroSCORE; 0.836 (95% CI: 0.731–0.942) for local EuroSCORE (logistic); 0.978 (95% CI: 0.937–1) for Local EuroSCORE (SVM); and 0.832 (95% CI: 0.723–0.941) for APACHE II model. The HL test showed good calibration for the local EuroSCORE (SVM), APACHE II model and local EuroSCORE (logistic) (P = 0.823, P = 0.748 and P = 0.06 respectively); but there was a significant difference between expected and observed mortality according to EuroSCORE model (P = 0.033).

Conclusion:

We detected logistic EuroSCORE risk model is not applicable on Iranian patients undergoing CABG surgery.

The EuroSCORE: a neglected measure of medium-term survival following cardiac surgery

OBJECTIVES

EuroSCORE is used to predict operative mortality following cardiac surgery. There are limited data to assess the ability of EuroSCORE to predict medium- to long-term survival. We aimed to test the ability of EuroSCORE to predict mid-term survival following cardiac surgery.

METHODS

We analysed prospectively collected data from all patients undergoing cardiac surgery in an urban tertiary cardiac centre over a 6-year period. All-cause mortality following cardiac surgery was determined via Office of National Statistics data. Patients were grouped into all comers, coronary artery bypass graft (CABG), isolated aortic valve replacement (AVR), isolated mitral valve repair and replacement (MVR) and combined AVR/MVR and CABG. Each group was separated into EuroSCORE quartiles. Kaplan-Meier curves were used to calculate 6-year actuarial survival. Log-rank test was used to calculate the P-value. C-statistic discriminated the ability of the EuroSCORE to predict medium-term survival.

RESULTS

A total of 9022 consecutive patients were identified. The mean age was 66.86 years, 73.7% were male. The cases were grouped according to their additive EuroSCORE into 0-5 (n = 5369), 6-10 (n = 3059), 11-15 (n = 506) and >15 (n = 93). Median follow-up was 2.92 years. The 6-year survival was 88.5, 71.8, 52.5 and 39.5%, respectively. The P-value for all operative categories was significant. The C-statistic was 0.68 (all comers), 0.72 for isolated MVR, 0.65 (isolated CABG), 0.62 (isolated AVR) and 0.69 (combined AVR/MVR and CABG).

CONCLUSIONS

Additive EuroSCORE may be used to predict medium-term survival in patients undergoing cardiac surgery; increasing additive EuroSCORE resulting in significant decreases in survival. It is a good predictive tool for patients undergoing isolated MVR and a fair tool for patients undergoing the remaining operative procedures studied.

Evaluation of Quality Of Life after Cardiac Surgery in High-Risk Patients

<p><b>Background:</b> Conventionally, there is controversy over subjecting high-risk patients to cardiac operations, due to major postoperative complications. Higher survival rates and less morbidity as well as better quality of life can be good predictors of the outcome of surgery. This study evaluates the quality of life before and 12 months after cardiac operations on high-risk patients.</p><p><b>Methods:</b> In this study, the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II was used to separate high-risk patients from others. The quality of life was assessed using the Medical Outcomes Study 36-item Short Form Health Survey (SF-36) before surgery and one year afterward. Based on SF-36, the score for each of the eight different dimensions of the quality of life was quantified; and, their differences between pre-surgery and post-follow up period were analyzed.</p><p><b>Results:</b> 126 high-risk patients were included in this study. The mean age of the patients was 64.29 � 12.35 years. The median of EuroSCORE II score in these cases was 6.83 (6.04-25.98). The results reveal that the majority of the quality of life dimensions, except mental health, improved significantly after the follow-up period.</p><p><b>Conclusion:</b> Cardiac surgery on high-risk patients can noticeably promote the different aspects of their quality of life; although, such improvements should be considered against surgical complications.</p>

Applicability of two international risk scores in cardiac surgery in a reference center in Brazil

Background

The applicability of international risk scores in heart surgery (HS) is not well defined in centers outside of North America and Europe.

Objective

To evaluate the capacity of the Parsonnet Bernstein 2000 (BP) and EuroSCORE (ES) in predicting in-hospital mortality (IHM) in patients undergoing HS at a reference hospital in Brazil and to identify risk predictors (RP).

Methods

Retrospective cohort study of 1,065 patients, with 60.3% patients underwent coronary artery bypass grafting (CABG), 32.7%, valve surgery and 7.0%, CABG combined with valve surgery. Additive and logistic scores models, the area under the ROC (Receiver Operating Characteristic) curve (AUC) and the standardized mortality ratio (SMR) were calculated. Multivariate logistic regression was performed to identify the RP.

Results

Overall mortality was 7.8%. The baseline characteristics of the patients were significantly different in relation to BP and ES. AUCs of the logistic and additive BP were 0.72 (95% CI, from 0.66 to 0.78 p = 0.74), and of ES they were 0.73 (95% CI; 0.67 to 0.79 p = 0.80). The calculation of the SMR in BP was 1.59 (95% CI; 1.27 to 1.99) and in ES, 1.43 (95% CI; 1.14 to 1.79). Seven RP of IHM were identified: age, serum creatinine > 2.26 mg/dL, active endocarditis, systolic pulmonary arterial pressure > 60 mmHg, one or more previous HS, CABG combined with valve surgery and diabetes mellitus.

Conclusion

Local scores, based on the real situation of local populations, must be developed for better assessment of risk in cardiac surgery.

[Evaluation of results in coronary surgery using EuroSCORE]

INTRODUCTION

The European System for Cardiac Operative Risk Evaluation (EuroSCORE) was developed in order to predict operative risk in cardiac surgery and to assess the quality of the cardio-surgical care. Introduction of the uniform terminology in result evaluation process leads to the significant improvement in measuring and evaluation of surgical treatment quality.

OBJECTIVE

The aim of the study was to evaluate our results in isolated coronary surgery using the EuroSCORE.

METHODS

The study was done respectively by analysing predicted mortality according to the EuroSCORE model and observed operative risk in 4,675 coronary patients operated at our Clinic during the period 2001-2008. For statistical analyses, the Pearson, Chi-square and ANOVA tests were used.

RESULTS

The total postoperative mortality predicted by the EuroSCORE was 2.9 +/- 2.25, while the observed one was 2.2%. When the scoring system and observed results were compared over the years, a considerably lower observed mortality was found during the last 4 years. Overall average number of distal anastomoses was 2.62 +/- 0.84. During the period 2004-2008, the average number of coronary anastomoses increased over the years reaching the value of 2.77 +/- 0.88. The difference is at the level of statistical significance with the trend of further increase. Percentage of the patients with single or double graft myocardial revascularization decreases, while the number of the patients with triple or more bypasses increases.

CONCLUSION

During the last years, the results in isolated coronary surgery have considerably improved. The EuroSCORE overestimates operative risk. In order to improve its predictive value, the model should be recalibrated.

[Trends of risk factors in coronary surgery]

INTRODUCTION

In current era of widespread use of percutaneous coronary interventions (PCI), it is debatable whether coronary artery by-pass graft (CABG) patients are at higher risk.

OBJECTIVE

The aim of the study was to evaluate trends in risk profile of isolated CABG patients.

METHODS

By analysing the EuroSCORE and its risk factors, we reviewed a consecutive group of 4675 isolated CABG patients, operated on during the last 8 years (2001-2008) at our Clinic. The number of PCI patients was compared to the number of CABG patients. For statistical analyses, Pearson's chi-square and ANOVA tests were used.

RESULTS

The number of PCI increased from 159 to 1595 (p < 0.001), and the number of CABG from 557 to 656 (p < 0.001). The mean EuroSCORE increased from 2.74 to 2.92 (p = 0.06). The frequency of the following risk factors did not change over years: female gender, previous cardiac surgery, serum creatinine > 200 micromol/l, left ventricular dysfunction and postinfarct ventricular septal rupture. Chronic pulmonary disease, neurological dysfunction, and unstable pectoral angina declined significantly (p < 0.001). Critical preoperative care declined from 3.1% in 2001 to 0.5% in 2005, than increased and during the last 3 years did not change (2.3%). The mean age increased from 56.8 to 60.7 (p < 0.001) and extracardiac arteriopathy increased from 9.2% to 22.9% (p < 0.001). Recent preoperative myocardial infarction increased from 11% to 15.1% (p = 0.021), while emergency operations increased from 0.9% to 4.0% (p = 0.001).

CONCLUSION

The number of CABG increases despite the enlargement of PCI. The risk for isolated CABG given by EuroSCORE increases over years. The risk factors, significantly contributing to higher EuroSCORE are: older age, extracardiac arteriopathy, recent myocardial infarction and emergency operation.

Correlation between EuroSCORE and intensive care unit length of stay after coronary surgery

During the last several years many authors have found that the European System for Cardiac Operative Risk Evaluation is useful in the prediction of not only postoperative mortality but also of the length of stay in the intensive care unit, complication rate and overall treatment expenses. This study included 329 patients who had undergone isolated surgical myocardial revascularization at our Department during the period from January 1st to June 6th, 2008. For the operative risk evaluation, the additive European System for Cardiac Operative Risk Evaluaion was used. In group I (low risk 0-2%) there were 144 patients (43.7%), whereas group II (medium risk 3-5%) and group III (high risk > or = 6%) included 141 (42.8%) and 44 (13.4%) patients, respectively. The length of stay in the intensive care unit was 25.56, 32.43 and 49.59 hours for groups I, II and III, respectively. The difference in the mean length of stay in the intensive care unit between the groups was highly statistically significant (p < 0.001) with a positive correlation (R = 0.193; p < 0.001). There is a positive correlation in patients who had undergone surgical myocardial revascularization in terms of operative risk expressed by the additive European System for Cardiac Operative Risk Evaluation and length of stay in the intensive care unit, total intubation period and development of early postoperative complications.

Are coronary angiograms of value in the risk stratification of patients undergoing coronary artery bypass surgery?

INTRODUCTION

There are currently more than 20 risk-scoring systems that attempt to predict peri-operative mortality following coronary artery bypass surgery (CABG). All these scoring systems use objective criteria to assess operative risk. Angiographic data are currently not included in any of these systems. This pilot study assessed the value of coronary angiography in predicting peri-operative mortality following CABG.

PATIENTS AND METHODS

Fourteen patients who died following first-time isolated CABG surgery were identified. These were matched with 14 patients of similar age, sex, left ventricle function and European System for Cardiac Operative Risk Evaluation (EuroSCORE). A panel of 25 clinicians were given details of the patients' age, sex, diabetic status, family history, smoking history, hypertensive status, lipid status, pre-operative symptoms, left ventricle ejection fraction and weight and shown the coronary angiograms of the patient. They were asked to predict the outcome following CABG for each patient.

RESULTS

Receiver operator characteristic curves were constructed and the area under the curves calculated and analysed using a commercially available statistical package (PRISM). The area under the curve for the group was 0.6820 for the group. Consultant clinicians achieved an area of 0.6789 versus their trainees 0.6844 (P = NS). The cardiologists achieved an area of 0.7063 versus the cardiothoracic surgeons 0.6491 (P = NS).

CONCLUSIONS

Despite the EuroSCORE predicting equal risk for the two groups of patients, it would appear that clinicians are able to identify individual higher risk patients by assessing pre-operatively the quality of the patient's coronary vasculature. Although the clinicians were able to predict individual patient mortality better than the EuroSCORE, the area under the curve indicates that it is not a robust method and clinicians, with all the clinical information to hand, are only moderately good at predicting the outcome following coronary artery bypass surgery.

Radial artery graft flowmetry is better than saphenous vein on postero-lateral wall

BACKGROUND

Although general agreement exists on internal mammary graft as the first conduit, the second choice is still questioned. Despite radial artery (RA) grafting has been suggested, saphenous veins (SV) continue to be extensively used.

METHODS

A prospective series of isolated RA-CABG (150 patients) or SV-CABG (180 patients), performed either off-pump (OP-CABG) and on-pump (CPB-CABG), in diabetics and non-diabetics, in elderly and young patients, during the last 5-years at a single institution were evaluated. RA was harvested with harmonic scalpel, flowmetry was performed with a transit-time flowmeter (TTF). Graft flow reserve (GFR) was calculated with intra-aortic balloon-pump. Follow-up was collected by outpatient clinic database or by telephone interview with general practitioners.

RESULTS

The 2 groups showed comparable preoperative and intraoperative variables. Mortality, morbidity, myocardial infarction, troponin I leakage, and echocardiographic parameters were comparable (p=NS). RA-CABG demonstrated significantly higher TTF maximum, mean and minimum flow (p<.001) with lower Pulsatility Index (p<.001), either in the circumflex and the right coronaries. Compared to SVG-grafting, significantly higher GFR was found in RA-CABG on the circumflex (p=.001) and right (p=.028) coronaries. 38.1+/-0.9 SE months follow-up resulted in higher survival and freedom from cardiac events in RA-CABG. Better TTF and GFR were demonstrated in OP-CABG, CPB-CABG, diabetics, non-diabetics, either on the circumflex and right coronary systems (p<.05). Better mean flow was detected in RA-CABG on the circumflex in the elderly (p=.04) and the young (p=.05).

CONCLUSIONS

RA-CABG demonstrated better TTF and GFR results compared to SV-CABG. These data may contribute to explain the survival benefit of arterial revascularization already reported.

Elevated glycosylated haemoglobin (HbA1c) is a risk marker in coronary artery bypass surgery

OBJECTIVE

To evaluate if glycosylated haemoglobin 1 (HbA1c) was associated with increased risk of infection and mortality after coronary artery bypass grafting (CABG).

DESIGN

Prospective observational study. Preoperative HbA1c concentrations were correlated to outcome in patients followed for an average of 3.5 years after CABG.

RESULTS

HbA1c was > or =6% in 68% of 161 patients with diabetes mellitus (DM) and in 3% of 444 patients without DM. Superficial sternal wound infection was observed in 13.9% if HbA1c > or =6% versus in 5.5% if <6% (p=0.007). Mediastinitis occurred in 4.9% if HbA1c > or =6% and in 2.1% if HbA1c <6% (p=0.20) (Hazard ratio (HR) 1.9, 95% CI 0.6-5.9). Follow-up mortality was 18.9% in patients with HbA1c > or =6% compared to 4.1% if HbA1c <6% (p<0.001) with HR 5.4, (95% CI 3.0-10.0) after multivariable adjustment. The risk of death was similar regardless of DM diagnosis.

CONCLUSIONS

HbA1c > or =6% was associated with an increased risk of postoperative superficial sternal wound infections and a trend for higher mediastinitis rate and significantly higher mortality three years after CABG.

Influence of diabetes mellitus on long-term survival in systematic off-pump coronary artery bypass surgery

BACKGROUND

Diabetic patients generally present a more diffuse and calcified coronary artery disease than nondiabetic patients that can affect long-term outcome especially if an off-pump coronary artery bybass graft (OPCABG) technique is used. The aim of this study was to compare long-term results of OPCABG surgery for diabetic and nondiabetic patients.

METHODS

This is a retrospective analysis of prospectively gathered data over a 10-year period of 1,000 consecutive and systematic OPCABG patients operated on between September 1996 and April 2004. Average follow-up period was 66 +/- 28 months and was 97% complete. Overall survival as well as occurrence of major adverse cardiac events in diabetic and nondiabetic patients were specifically studied.

RESULTS

In all, 278 diabetic patients and 722 nondiabetic patients were treated. There was no difference in 30-day mortality between the two groups (p = 0.70). Diabetic patients had more postoperative acute renal insufficiency (p = 0.01) and infections (sepsis; p = 0.002), and deep sternal infections (p = 0.04) Ten-year survival (p = 0.006) and survival free of major adverse cardiac events (p = 0.02) was decreased in the diabetic group. Age (hazard ratio [HR] = 1.06), peripheral vascular disease (HR = 1.72), carotid disease (HR = 1.53), congestive heart failure (HR = 1.51), incomplete revascularization (HR = 2.37), chronic renal insufficiency (HR = 1.93), left ventricular ejection fraction (HR = 0.13), and a lesser use of multiple internal thoracic artery grafts (HR = 0.67), but not diabetes mellitus (p = 0.13) were significant determinants of long-term mortality. Similarly, peripheral vascular disease (HR = 1.92), chronic renal insufficiency (HR = 2.36), emergent operation (HR = 1.71), chronic obstructive pulmonary disease (HR = 1.76), previous percutaneous coronary intervention (HR = 1.66), left ventricular ejection fraction (HR = 0.26), ischemic mitral regurgitation (HR = 1.83), and a lesser use of multiple internal thoracic artery grafts (HR = 0.72) were determinants of decreased survival free of major adverse cardiac events but not diabetes (p = 0.2). Breaking down the major adverse cardiac events, diabetes was found an independent predictive factor of recurrent myocardial infarction (HR = 1.85) and a borderline cause of readmission for congestive heart failure (p = 0.06). Need for new revascularization was comparable for both population (p = 0.37).

CONCLUSIONS

In our series of OPCABG surgery patients, diabetic patients had a comparative operative mortality and perioperative myocardial infarction rate as nondiabetic patients. However, they had an increased prevalence of postoperative acute renal insufficiency and infections. They also had a worse outcome than nondiabetic patients, but that was mainly due to a higher prevalence of preoperative comorbidities and a lesser use of multiple internal thoracic artery grafts. However, diabetes itself was a potential risk factor for long-term occurrence of myocardial infarction and congestive heart failure.

Intraoperative behavior of arterial grafts in the elderly and the young: a flowmetric systematic analysis

Extensive arterial grafting (Art-CABG) in the elderly is still questioned due to the reduced life expectancy and the supposed higher periprocedural risk. Reports further demonstrated accelerated atherosclerosis of arterial grafts in the elderly, with hampered short-term and long-term results. We reviewed our experience of patients undergoing Art-CABG between January 2003 and January 2007, divided into two groups: the elderly (238 patients > or = 70 years; Group A) and the young (195 patients < or = 60 years; Group B). Transit time flowmetric (TTF) maximum and mean flow, pulsatility index (PI), and graft flow reserve (GFR) were compared. Hospital outcome was analyzed. Hospital mortality, need for intra-aortic balloon pump, troponin I, and echocardiographic segmental kinetics were comparable between the two groups (P = not significant [NS]). Stratifying patients for target vessels and type of arterial CABG, no differences in TTF results were recorded between the two groups either on-pump (P = NS) and off-pump (P = NS), both for the two internal mammary arteries (P = NS irrespective of the target vessel) and the radial artery conduits (P = NS irrespective of the target vessel). Although graft flow reserve was significantly recruited in all patients (P < 0.05 in young and elderly, either on-pump and off-pump, irrespective of the arterial conduit and the grafted vessel), GFR of all arterial grafts was comparable between elderly and young patients, either on-pump (P = NS) or off-pump (P = NS). Art-CABG showed similar TTF results in elderly and young patients, regardless of the arterial conduit, target vessel, or surgical technique employed. These functional results supported the reported survival benefit of arterial revascularization in the elderly.

Impact of cardiothoracic resident turnover on mortality after cardiac surgery: a dynamic human factor

BACKGROUND

The study was designed to determine whether cardiac surgical outcomes are affected during times of major turnover of cardiothoracic resident surgical staff and at the beginning versus the end of their training periods.

METHODS

This observational cohort study analyzed data from cardiac operations between April 1996 and March 2006 at a single institution. In-hospital mortality and other outcomes were compared between operations done during months of major change in resident staff rotation (July, August, January, February, n = 5,517) and the rest of the year (n = 10,773). We also compared outcomes at the beginning and end of surgical rotation for cardiothoracic residents. Adjustment was made for EuroSCORE (European System for Cardiac Operative Risk Evaluation), year of operation, and surgeon resident status. Analyses were done within surgery procedure subgroups of isolated coronary artery bypass graft surgery (CABG) and complex operations (CABG combined with other procedures).

RESULTS

Patient populations in the groups were similar. After risk adjustment, there was a significant increase in hospital mortality for the complex cases during months of resident staff change compared with rest of the year (odds ratio 1.3, 95% confidence interval: 1.3, 1.4; p = 0.02). There was, however, no significant difference in mortality for the CABG only cases (odds ratio 1.1, 95% confidence interval: 0.8, 1.4; p = 0.61). Risk-adjusted mortality after operations done by residents was the same at the start and finish of their surgical rotation. During the change months, the surgery time was 2.2 minutes longer on average in CABG operations (95% confidence interval: 0.3, 4.0; p = 0.02), and no different in combined cases.

CONCLUSIONS

Periods of major change in resident surgical staff are associated with increased risk-adjusted in-hospital mortality after complex cardiac operations but not after CABG alone.

Single versus sequential saphenous vein grafting of the circumflex system: a flowmetric study

OBJECTIVE

We sought to evaluate if patients with proximal critical circumflex (CX) lesions did better with single SV-CABG on the best obtuse marginal (OM), or with sequential SV-CABG on two OM branches.

DESIGN

Ninety patients were prospectively randomised to single SV-CABG on the best OM (sSV-CABG-45 patients; Group A) or to sequential SV-CABG on 2 OM (seqSV-CABG 45 patients; Group B). Transit-time flowmetry (TTF), and graft flow reserve were evaluated. Recurrent angina, acute myocardial infarction, readmission for coronary reintervention were defined "treatment failure" during follow-up.

RESULTS

SeqSV-CABG showed better intraoperative maximum (119.1+/-57.5 ml/min vs. sSV-CABG 62.4+/-29.6; p=0.001), mean (56.3+/-31.5 ml/min vs. 30.8+/-12.8; p=0.0001), minimum flow (22.8+/-9.2 ml/min vs. 11.8+/-8.9; p=0.001) and P.I. (0.71+/-0.4 vs.1.46+/-0.9; p=0.006). Graft flow reserve also proved to be higher (95.4+/-29.7 ml/min mean flow vs. sSV-CABG 42.3+/-15.2 ml/min mean flow; p=0.0001; flow reserve 1.72+/-0.99 vs 1.32+/-1.09; p=0.001) as well as freedom from treatment failure (97.5+/-0.5% vs 88.7+/-0.4%; p=0.05).

CONCLUSIONS

SeqSV-CABG showed higher TTF flows, with no incremental risk for perioperative morbidity. Higher flows and graft flow reserve may allow lower treatment failure at mid-term follow-up.

Safety aspects of aprotinin therapy in cardiac surgery patients

Aprotinin is the only agent with Class A Level 1 evidence for reduction in rates of transfusion and return to operating theatre to control bleeding after heart surgery. Principal on the list of safety issues raised over the years are increased risk for: a) thrombosis; and b) renal dysfunction. With multiple administrations, hypersensitivity reactions have emerged as a further safety concern. This review discusses these issues, based on the examination of > 500 published articles. The article also specifically places in context the data presented recently from the observational McSPI database analysis. This report suggested that aprotinin should be withdrawn from human use as serious safety issues have been ignored or missed, an inference not in agreement with the majority of the human safety literature.

Valor predictivo del modelo EuroSCORE en la cirugía cardíaca de nuestro centro

OBJECTIVE

The use of risk prediction models in cardiac surgery makes it possible to compare and evaluate health care quality between different institutions in countries. This study aimed to assess the performance of the European System for Cardiac Operative Risk Evaluation (EuroSCORE) model in estimating the risk of mortality of cardiac surgery patients of our hospital.

PATIENTS AND METHODS

The additive and logistic EuroSCORE models were applied to all patients who underwent cardiac surgery with extracorporeal circulation from the time the cardiac surgery unit was opened in our center in November 2002 until February 2006. All data were obtained prospectively when the patients were admitted to the Intensive Care Unit. Mortality observed was compared with that estimated in the following subgroups: global cardiac surgery, isolated coronary surgery, isolated valvular surgery, combined valvular and coronary surgery and thoracic aorta surgery. Model discrimination was tested by determining the area under the receiver operating characteristic (ROC) curve.

RESULTS

We studied 1,053 patients who had several differences with the EuroScore model population. Overall observed mortality was 2.2% (95% CI 1.2 - 3.1). The EuroSCORE models overestimated mortality (additive predicted 5%, logistic predicted 4.6%). Mortality of coronary bypass graft surgery was 1.2% and both EuroSCORE models overestimated it. Discriminative power of both models was good with an Area under ROC curve for both models of 0.78 and 0.79.

CONCLUSIONS

The use of both EuroSCORE models overestimated overall observed mortality and that of the different surgical subgroups of cardiac surgery performed in our institution.

EuroSCORE Predicts Immediate and Late Outcome After Coronary Artery Bypass Surgery

BACKGROUND

The European system for cardiac operative risk evaluation score (EuroSCORE) has been shown to be of value in identifying patients at high risk for adverse immediate postoperative outcome after adult cardiac surgery. The aim of the present study was to evaluate EuroSCORE in predicting the 12-year outcome of patients who underwent on-pump coronary artery bypass surgery (CABG).

METHODS

We calculated the EuroSCORE in 917 patients who underwent CABG. The median follow-up was 11.7 years.

RESULTS

Both additive and logistic EuroSCORE had an area under the receiver operating characteristic curve of 0.856 for prediction of 30-day postoperative death. Among 912 operative survivors, the 10-year survival rates according to quintiles of additive EuroSCORE were 87.9%, 83.9%, 85.2%, 76.0%, and 51.3% (p < 0.0001). The 10-year survival rates according to quintiles of logistic EuroSCORE were 87.9%, 85.4%, 86.5%, 76.9%, and 58.9% (p < 0.0001).

CONCLUSIONS

EuroSCORE is a relevant predictor of immediate and late outcome after on-pump CABG.

Comparison of 19 pre-operative risk stratification models in open-heart surgery

AIMS

To compare 19 risk score algorithms with regard to their validity to predict 30-day and 1-year mortality after cardiac surgery.

METHODS AND RESULTS

Risk factors for patients undergoing heart surgery between 1996 and 2001 at a single centre were prospectively collected. Receiver operating characteristics (ROC) curves were used to describe the performance and accuracy. Survival at 1 year and cause of death were obtained in all cases. The study included 6222 cardiac surgical procedures. Actual mortality was 2.9% at 30 days and 6.1% at 1 year. Discriminatory power for 30-day and 1-year mortality in cardiac surgery was highest for logistic (0.84 and 0.77) and additive (0.84 and 0.77) European System for Cardiac Operative Risk Evaluation (EuroSCORE) algorithms, followed by Cleveland Clinic (0.82 and 0.76) and Magovern (0.82 and 0.76) scoring systems. None of the other 15 risk algorithms had a significantly better discriminatory power than these four. In coronary artery bypass grafting (CABG)-only surgery, EuroSCORE followed by New York State (NYS) and Cleveland Clinic risk score showed the highest discriminatory power for 30-day and 1-year mortality.

CONCLUSION

EuroSCORE, Cleveland Clinic, and Magovern risk algorithms showed superior performance and accuracy in open-heart surgery, and EuroSCORE, NYS, and Cleveland Clinic in CABG-only surgery. Although the models were originally designed to predict early mortality, the 1-year mortality prediction was also reasonably accurate.

Does Diabetes Affect the Postoperative Outcomes After Total Arterial Off-Pump Coronary Bypass Surgery in Multivessel Disease?

BACKGROUND

Previous studies have reported conflicting results regarding the adverse effects of diabetes on surgical outcomes after coronary artery bypass grafting (CABG). We reviewed our experience to determine the impact of diabetes on early and midterm surgical outcomes of patients with multivessel disease who underwent total arterial revascularization with avoidance of cardiopulmonary bypass.

METHODS

Between January 1998 and December 2003, 517 patients with multivessel disease underwent total arterial off-pump CABG; 214 were diabetic (DM group) and 303 were nondiabetic (NDM group). The DM group was sicker than the NDM group (more left ventricular dysfunction, postinfarction angina, previous myocardial infarction, and chronic renal failure). Mean follow-up period was 34 +/- 17 months. The multivariate risk factors for operative mortality, one-year angiographic patency, and midterm survival were analyzed.

RESULTS

Mean numbers of distal anastomoses were not different between the two groups (DM, 3.1 +/- 0.9; NDM, 3.0 +/- 0.8). Operative mortality was 1.4% (DM, 1.4% vs NDM, 1.3%; p = not significant [ns]). No differences were found in the incidences of postoperative morbidities, including mediastinitis and superficial wound problems, between the two groups. In immediate postoperative angiography, the patency rates were 99.2% in the DM and 98.9% in the NDM group (p = ns). One-year patency rates in angiography were also similar between the two groups (DM, 96.0%; NDM, 95.4%; p = ns). Multivariate analysis indicated that diabetes was not an independent risk factor of steno-occlusion at one-year follow-up angiography. Five-year cumulative survival was 87.7 +/- 4.1% in the DM, and 94.2 +/- 1.4% in NDM (p = ns) group. Five-year freedom from cardiac death was 99.0 +/- 0.7% in the DM, and 97.4 +/- 1.0% in the NDM (p = ns) group. Old age (age > 75 years) and chronic renal failure were independent risk factors for lower midterm survival. Our study failed to demonstrate that diabetes was an independent risk factor for lower midterm survival.

CONCLUSIONS

Diabetes mellitus did not affect the early postoperative and midterm results, including one-year graft patency, in patients with multivessel disease undergoing total arterial and off-pump CABG.

Canonical Correlation Analysis of Risk Factors and Clinical Outcomes in Cardiac Surgery

Assessment of the association between risk factors and outcomes in cardiac surgery is a complex problem. The aim of this study was to explore the relationship between possible risk factors and several clinical outcomes in cardiac surgery by using canonical correlation analysis (CCA). This retrospective study of 2605 consecutive adult patients who underwent cardiac surgery, evaluated 74 potential risk factors and up to 12 outcomes by canonical correlation analysis. For three serious outcomes, sternal wound complications/mediastinitis, cerebral complications, and perioperative myocardial infarctions, CCA was preceded by univariate analyses and backward stepwise multivariate logistic regression analyses. The CCA suggests that the major risk factors for complications in these models are intraoperative and postoperative risk factors. The power of risk prediction models developed with multivariate regression analysis can be enhanced by application of canonical correlation analysis, thereby offering new ways of analyzing and interpreting sets of potential risk factors in relation to sets of clinical outcomes.

Non-dialysis-dependent renal dysfunction and cardiac surgery-an assessment of perioperative risk factors

OBJECTIVE

In most reports, dialysis-dependent patients are known to be at increased risk for perioperative morbidity and mortality after cardiac surgical procedures.(1-7) However, the preoperative factors important for risk stratification of patients who have renal insufficiency but are not dialysis dependent are unclear. We set forth to ascertain preoperative risk factors important for predicting 2 endpoints: (1) dialysis at discharge and (2) hospital death.

DESIGN

A retrospective analysis.

SETTING

A tertiary referral center.

PATIENTS

From a database of patients undergoing cardiopulmonary bypass over a 6-year period, 150 patients were chosen for study based on their preoperative creatinine being greater than 1.5 mg/dl.

INTERVENTIONS

Routine monitoring and care of patients after their cardiac surgical procedures.

MEASUREMENTS AND MAIN RESULTS

Many preoperative, perioperative, and postoperative variables were measured. Multivariable regression was used for data analysis. There were 21 (14%) hospital deaths and 7 (5%) patients who were not on preoperative dialysis who required dialysis at discharge. Preoperative risk factors for hospital death were the patients' New York Heart Association (NYHA) class (p = 0.004) and emergency status (p = 0.005). Preoperative risk factors for dialysis at discharge were female gender (p = 0.02), emergency status of procedure (p = 0.01), and preoperative creatinine (p = 0.03).

CONCLUSIONS

These data allow for a more accurate assessment of risk stratification in this group of patients with renal insufficiency but who are not dependent on dialysis. Given the data presented here and other studies that report good outcomes for patients with renal disease after cardiac surgical procedures,(8-10) earlier operative intervention for coronary disease in this subset of patients might be warranted.

Effect of Diabetes on Outcome and Changes in Quality of Life After Coronary Artery Bypass Grafting

BACKGROUND

An increasing proportion of patients undergoing coronary artery bypass grafting are diabetics who are known to carry a higher mortality and morbidity in association with operation, but data on whether health-related quality of life improves similarly after coronary artery bypass grafting in diabetic and nondiabetic patients are limited. We assessed in detail changes in health-related quality of life (RAND-36 Health Survey) during the first year after coronary artery bypass grafting.

METHODS

Seventy-four of the 508 patients (14.6%) operated on in a single institution had a history of diabetes and were compared to nondiabetics. The RAND-36 Health Survey was used as an indicator of quality of life. Assessments were made preoperatively and repeated 12 months later.

RESULTS

Thirty-day mortality was 2.7% versus 1.6% (p = 0.511) and one-year survival was 94.6% versus 97.0% (p = 0.287) in the diabetics and nondiabetics, respectively. Diabetics improved significantly (p < 0.005) in seven, nondiabetics (p < 0.001) in all eight RAND-36 dimensions. Physical component summary and mental component summary scores on the RAND-36 improved significantly (p < 0.001) in diabetics as well as in nondiabetics. Both groups experienced closely similar freedom from anginal symptoms at one year (86.2% vs 90.5%, p = 0.280).

CONCLUSIONS

Although diabetic patients differ from nondiabetics having slightly inferior quality of life before and one year after coronary artery bypass grafting, they gain similar improvement of quality of life in one year after surgery when compared to nondiabetics.

Validation of four different risk stratification systems in patients undergoing off-pump coronary artery bypass surgery: a UK multicentre analysis of 2223 patients

BACKGROUND

Various risk stratification systems have been developed in coronary artery bypass graft surgery (CABG), based mainly on patients undergoing procedures with cardiopulmonary bypass.

OBJECTIVE

To assess the validity and applicability of the Parsonnet score, the EuroSCORE, the American College of Cardiology/American Heart Association (ACC/AHA) system, and the UK CABG Bayes model in patients undergoing off-pump coronary artery bypass surgery (OPCAB) in the UK.

METHODS

Data on 2223 patients who underwent OPCAB in eight cardiac surgical centres were collected. Predicted mortality risk scores were calculated using the four systems and compared with observed mortality. Calibration was assessed by the Hosmer-Lemeshow (HL) test. Discrimination was assessed using the receiver operating characteristic (ROC) curve area.

RESULTS

30 of 2223 patients (1.3%) died in hospital. For the Parsonnet score the HL test was significant (p < 0.001) and the receiver operating characteristic curve (ROC) area was 0.74. For the EuroSCORE the HL test was also significant (p = 0.008) and the ROC area was 0.75. For the ACC/AHA system the HL test was non-significant (p = 0.7) and the ROC area was 0.75. For the UK CABG Bayes model the HL test was also non-significant (p = 0.3) and the ROC area was 0.81.

CONCLUSIONS

The UK CABG Bayes model is reasonably well calibrated and provides good discrimination when applied to OPCAB patients in the UK. Among the other three systems, the ACC/AHA system is well calibrated but its discrimination power was less than for the UK CABG Bayes model. These data suggest that the UK CABG Bayes model could be an appropriate risk stratification system to use for patients undergoing OPCAB in the UK.

[Cardiac surgery in elderly patients]

OBJECTIVE

The morbimortality of elderly patients, (age 70 years or older), who underwent surgery for valvular and coronary artery disease in the last 17 years was analyzed.

PATIENTS AND METHOD

A total of 1,305 patients (654 valvular, 531 coronary and 120 combined) operated from January 1985 to December 2000 were retrospectively studied. Mean age was 73.7 years. We analyzed the progression of the pathology, comorbidity, and results. A second retrospective analysis was made of patients who underwent surgery in the last three years (436 patients) to determine the relation between preoperative comorbidity and postoperative evolution.

RESULTS

The mean hospital mortality was 16% (18% valvular, 11% coronary artery, and 23% combined). In the last three years this mortality was reduced to 11% (15.17, 6.26, and 16.18%, respectively) despite an increase in comorbidity. Comorbidity and complications increased with age (p < 0.05). Mean hospital stay was 15.5 days and the stay in intensive/semi-intensive care was 5 days. Independent risk factors of postoperative complications were creatinine levels > 2 mg/dl, combined surgery, and prior surgery. Predictors of death were prior surgery, valvular surgery, and combined surgery, with a clear tendency in the case of obesity. The presence of any complication in the postoperative period (renal or respiratory failure, infections, or myocardial infarction) was an independent predictor of mortality. Off-pump coronary surgery reduced mortality. In recent years, the mortality of patients operated without extracorporeal circulation has decreased from 5.71% to 4% for those who underwent extracorporeal circulation.

CONCLUSIONS

Nowadays, cardiac surgery in older patients accounts for more than 30% of our surgical activity. Mortality is being controlled although comorbidity is increasing. The difference with respect to younger people is due to comorbidity (creatinine > 2 mg/dl, combined surgery, and previous surgery) and the higher probability of complications (infections, renal, and respiratory complications), which worsens prognosis. We believe that off-pump coronary surgery helps to improve results.

Early postoperative outcome and medium-term survival in 540 diabetic and 2239 nondiabetic patients undergoing coronary artery bypass grafting

BACKGROUND

An increasing proportion of patients undergoing coronary artery bypass grafting (CABG) are diabetics. Patient characteristics, early postoperative outcome, and midterm survival in diabetic patients after CABG were investigated.

METHODS

A total of 2779 consecutive patients undergoing isolated CABG during 1995 to 1999 were studied, 19.4% of whom had diabetes mellitus. Demographic and peri-procedural data were registered prospectively in a computerized institutional database.

RESULTS

The diabetic group was younger and included a higher proportion of women, and patients with hypertension, triple-vessel disease, and unstable angina. They required a higher number of bypasses, and longer cross-clamp and cardiopulmonary bypass times. Intensive care unit and hospital stays were prolonged and the need for inotropic agents, hemotransfusions, and dialysis was higher in the diabetic group. Renal failure, stroke (4.3% versus 1.7%), mediastinitis, and wound infections were more frequently encountered. Thirty-day mortality was 2.6% versus 1.6% (p = 0.15). Cumulative 5-year survival was 84.4% versus 91.3% (p < 0.001).

CONCLUSIONS

Short-term mortality was acceptable in diabetic patients after CABG but they had increased postoperative morbidity in comparison with nondiabetic patients, particularly with regard to renal function, cerebral complications, and infections. Midterm survival was impaired in diabetic patients mainly because of a less favorable outcome in patients treated with insulin.

Cognitive deficit after aortic valve replacement

BACKGROUND

Impairment of cognitive brain function after coronary artery bypass grafting (CABG) is well known. In contrast the potential neurocognitive damage related to aortic valve replacement (AVR) is uncertain.

METHODS

In this contemporary case-matched control study we followed 30 patients (mean age 70 years) receiving isolated AVR with a biological prosthesis. A cohort of sex-and age-matched patients (n = 30, mean age 70 years) receiving CABG with cardiopulmonary bypass served as controls. Cognitive brain function was measured by means of auditory evoked P300 potentials (peak latencies, ms) before the operation and 7 days and 4 months after the operation. Additionally, two standard psychometric tests (Mini-Mental State Examination and the Trailmaking Test A) were performed.

RESULTS

In preoperative measures there was no difference between patients undergoing AVR and patients undergoing CABG (AVR 378 +/- 37 ms, CABG 374 +/- 32 ms, p = 0.629). One week after surgery P300 peak latencies were prolonged (impaired) in both groups compared with preoperative values (AVR 405 +/- 43 ms, p = 0.001; CABG 398 +/- 44 ms, p = 0.004). At this point of follow-up there was no difference between the groups (p = 0.607). Finally, 4 months after surgery P300 auditory evoked potentials returned to normal in the CABG group (380 +/- 24 ms, p = 0.940) while in contrast in the valve group they continued to become prolonged (worsened) compared with preoperative values (410 +/- 47 ms, p = 0.005). At this time of follow-up P300 peak latencies were prolonged in AVR patients as compared with CABG patients (p = 0.032). The Trailmaking Test A and Mini-Mental State Examination failed to discriminate any difference.

CONCLUSIONS

Four-month impairment of cognitive brain function is more pronounced in patients undergoing biological AVR as compared with age-matched control patients undergoing CABG. Further studies are needed to clarify the potential pathologic mechanisms causing an ongoing cognitive impairment in patients with biological aortic valve prostheses.

Single centre, single domain validation of the EuroSCORE on a consecutive sample of primary and repeat CABG

OBJECTIVES

Intra- and interdepartmental benchmarking require scoring systems with excellent performance on several properties: discrimination (resolution), reliability (calibration) and stability over the complete spectrum of peri-procedural risk. This single centre, single domain study validates the European system for cardiac operative risk evaluation (EuroSCORE) on an independent sample of primary and repeat coronary artery bypass grafting (CABG) patients and will evaluate these different properties.

METHODS

The study population is a consecutive series of 2051 isolated primary and repeat CABG patients, inclusive of patients in cardiogenic shock or resuscitation, operated on in a single institution from January 1997 to July 2000. The age of the patients was 66+/-9 years, 77% were males and 7% were repeat procedures. The EuroSCORE was 5.0+/-3%, with a range from 0 to 22. The studied event was in-hospital death, defined as mortality during hospital stay, which was unlimited in time and included a stay in a secondary hospital without discharge home.

RESULTS

The EuroSCORE predicted 102 deaths versus 81 deaths observed (P=0.14, Fisher exact test). The EuroSCORE described only 20% of the variance of in-hospital mortality. The EuroSCORE created an area under the receiver operating characteristic curve of 0.83+/-0.03. The highest discriminative accuracy was obtained with 8% EuroSCORE risk (only 64% sensitivity and 87% specificity). Further exploration identified an over score in the EuroSCORE range 0-8 (57%, P<0.0001). There was an equal score (-2%, P=1) in the range 9-11, but an under score in the range 12-22 (-133%, P=0.003).

CONCLUSIONS

On the condition that these single centre results could be extended to any European cardiac surgery centre, it can be concluded that the overall acceptable performance of the EuroSCORE is the result of an over score in the lower risk and insufficient correction in the higher risk spectrum. The EuroSCORE is probably refined enough for improved informed consent versus aggregated results but should only be used for inter-institutional benchmarking with great caution, preferably below the 12% risk pivot.

The challenge of departmental quality control in the reengineering towards off-pump coronary artery bypass grafting

OBJECTIVE

Off pump coronary surgery is a major reengineering effort of the surgical systems. There are no perfect tools available to guide every centre in the confrontation with the complete spectrum of risk and the limited number of events. This study analyses the use of a hospital mortality risk-stratifying system in the complete shift towards off-pump CABG.

METHODS

All 535 off-pump CABG patients from January 1997 till September 2000 underwent a comparison of their hospital mortality versus the EuroSCORE predictions. The mean risk predicted by the EuroSCORE was 4.5+/-3% (range 0-14) and the mean age was 65+/-10 years (range 36-89). The series includes 23 repeat procedures, also 77 patients with per oral or insulin-treated diabetes. The number of distal anastomoses was 2.5+/-1 and of arterial grafts 1.3+/-0.6.

RESULTS

The observed hospital mortality was 15 patients, 2.8% (Fisher exact test P=0.19 versus the EuroSCORE). The 1 and 3 month Kaplan-Meier survival, irrespective from hospital discharge, was 97.4+/-0.7 and 97.2+/-0.7%, respectively. A cumulative risk-adjusted mortality plot is constructed. The area under the ROC curve was 0.886. A stepwise sampling of patients according to increasing risk identified the difference between the EuroSCORE-predicted and observed hospital mortality for the complete spectrum of risk. The P value of this difference was 0.06 for the grouping including all patients from 0-5% risk (78% reduction), 0.04 for the grouping 0-8% risk (61% reduction), and 0.05 for the grouping 0-11% risk (52% reduction of risk). The loss of statistical significant difference was due to the inclusion of the patients at extremely high risk.

CONCLUSION

A hospital mortality risk-stratifying system can provide guidance but different and in depth approaches are mandatory to improve the insight, certainly in the presence of a large spectrum of risk.