Surgeons National Cardiac Surgery Database Research Articles

Association of perioperative transfusion of fresh frozen plasma and outcomes after cardiac surgery.

Fresh frozen plasma (FFP) transfusion is used to manage coagulopathy and bleeding in cardiac surgery patients despite uncertainty about its safety and effectiveness. We performed a propensity score matched analysis of the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database including patients from 39 centres from 2005 to 2018. We investigated the association of perioperative FFP transfusion with mortality and other clinical outcomes. Of 119,138 eligible patients, we successfully matched 13,131 FFP recipients with 13,131 controls. FFP transfusion was associated with 30-day mortality (odds ratio (OR), 1.41; 99% CI, 1.17-1.71; p < .0001), but not with long-term mortality (hazard ratio (HR), 0.92; 99% CI, 0.85-1.00; p = .007, Holm-Bonferroni α = 0.0004). FFP was also associated with return to theatre for bleeding (OR, 1.97; 99% CI, 1.66-2.34; p < .0001), prolonged intubation (OR, 1.15; 99% CI, 1.05-1.26; p < .0001) and increased chest tube drainage (Mean difference (MD) in mL, 131; 99% CI, 120-141; p < .0001). It was also associated with reduced postoperative creatinine levels (MD in g/L, -6.33; 99% CI, -10.28 to -2.38; p < .0001). In a multicentre, propensity score matched analysis, perioperative FFP transfusion was associated with increased 30-day mortality and had variable associations with secondary clinical outcomes.

Platelet versus fresh frozen plasma transfusion for coagulopathy in cardiac surgery patients.

Platelets (PLTS) and fresh frozen plasma (FFP) are often transfused in cardiac surgery patients for perioperative bleeding. Their relative effectiveness is unknown. We conducted an entropy-weighted retrospective cohort study using the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database. All adults undergoing cardiac surgery between 2005-2021 across 58 sites were included. The primary outcome was operative mortality. Of 174,796 eligible patients, 15,360 (8.79%) received PLTS in the absence of FFP and 6,189 (3.54%) patients received FFP in the absence of PLTS. The median cumulative dose was 1 unit of pooled platelets (IQR 1 to 3) and 2 units of FFP (IQR 0 to 4) respectively. After entropy weighting to achieve balanced cohorts, FFP was associated with increased perioperative (Risk Ratio [RR], 1.63; 95% Confidence Interval [CI], 1.40 to 1.91; P<0.001) and 1-year (RR, 1.50; 95% CI, 1.32 to 1.71; P<0.001) mortality. FFP was associated with increased rates of 4-hour chest drain tube output (Adjusted mean difference in ml, 28.37; 95% CI, 19.35 to 37.38; P<0.001), AKI (RR, 1.13; 95% CI, 1.01 to 1.27; P = 0.033) and readmission to ICU (RR, 1.24; 95% CI, 1.09 to 1.42; P = 0.001). In perioperative bleeding in cardiac surgery patient, platelets are associated with a relative mortality benefit over FFP. This information can be used by clinicians in their choice of procoagulant therapy in this setting.

Association of Perioperative Cryoprecipitate Transfusion and Mortality After Cardiac Surgery

BackgroundCryoprecipitate is often transfused in patients undergoing cardiac surgery. However, its safety and effectiveness remain uncertain. MethodsThis study was a propensity score–matched analysis of data from the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database. The study included adults undergoing cardiac surgery between 2005 and 2018 across 38 sites. The association between perioperative cryoprecipitate transfusion and clinical outcomes was estimated, with a primary outcome of operative mortality. ResultsOf 119,132 eligible patients, 11,239 (9.43%) patients received cryoprecipitate. The median cumulative dose was 8 U (interquartile range, 5-10 U). After propensity score matching, we matched 9055 cryoprecipitate recipients to 9055 control subjects. Postoperative cryoprecipitate transfusion was associated with reduced operative mortality (odds ratio [OR], 0.82; 99% CI, 0.69-0.97; P = .002) and long-term mortality (hazard ratio, 0.92; 99% CI, 0.87-0.97; P = .0042). It was also associated with a reduction in acute kidney injury (OR, 0.85; 99% CI, 0.73-0.98; P = .0037) and all-cause infection (OR, 0.77; 99% CI, 0.67-0.88; P < .0001). These findings were observed despite increased rates of return to the operating room (OR, 1.36; 99% CI, 1.22-1.51; P < .0001) and cumulative 4-hour postoperative chest tube output (adjusted mean difference in mL, 97.69; 99% CI, 81.65;113.74; P < .0001). ConclusionsIn a large, multicenter cohort study and after propensity score matching, perioperative transfusion of cryoprecipitate was associated with reduced operative and long-term mortality.

Preoperative identification of cardiac surgery patients at risk of receiving a platelet transfusion: The Australian Cardiac Surgery Platelet Transfusion (ACSePT) risk prediction tool.

Using the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database, significant predictors for PLT transfusion were identified by multivariate logistic regression. Using a development data set containing 2005 to 2016 data, the Australian Cardiac Surgery Platelet Transfusion (ACSePT) risk prediction tool was developed by assigning weights to each significant predictor that corresponded to a probability of PLT transfusion. The predicted probability for each score was compared to actual PLT transfusion occurrence in a validation (2017) data set. The development data set contained 38 independent variables and 91 521 observations. The validation data set contained 12 529 observations. The optimal model contained 23 variables significant at P < .001 and an area under the receiver operating characteristic (ROC) curve of 0.69 (95% confidence interval [CI], 0.68-0.69). ACSePT contained nine variables and had an area under the ROC curve of 0.66 (95% CI, 0.65-0.66) and overall predicted probability of PLT transfusion of 19.8% for the validation data set compared to an observed risk of 20.3%. The ACSePT risk prediction tool is the first scoring system to predict a cardiac surgery patient's risk of receiving a PLT transfusion. It can be used to identify patients at higher risk of receiving PLT transfusions for inclusion in clinical trials and by PLT inventory managers to predict PLT demand.

Urgent versus elective coronary artery bypass grafting in acute coronary artery syndrome

BackgroundIn this retrospective study, we aimed to evaluate the clinical outcomes, risk factors of mortality and prognosis after urgent coronary artery bypass grafting (CABG) in acute coronary syndrome (ACS) patients. MethodsOur study included 100 patients who underwent CABG for ACS (50 urgent and 50 elective). All patients were followed for 30 days after surgery, both clinically and echocardiographically. Data were analyzed using the SPSS software in accordance to the Society of Thoracic Surgeons (STS) National Cardiac Surgery Database guidelines. ResultsPatients in the urgent CABG group were of younger age (p = .03) and had a higher frequency of smoking (p = .04) and dyslipidemia (p = .004); otherwise, all baseline characteristics were comparable between the two groups. The cardiopulmonary bypass (CPB) (p = .003) and aortic cross-clamp times (p = .02) were significantly longer in the urgent CABG group compared to the elective CABG group. Although both groups had a relatively similar survival rate (p = .056), urgent CABG patients were more liable to postoperative myocardial infarction (p = .02), as well as prolonged ventilation time (p = .002) and hospital stay (p < .001). Our analysis showed that preoperative low ejection fraction (EF) (p = .03), use of inotropes (p = .002) and prolonged CPB time (p = .04) were independent risk factors for mortality after urgent CABG. ConclusionsUrgent CABG increased the risk of myocardial infarction and prolonged hospital stay in comparison to elective CABG. Moreover, preoperative low EF and prolonged CPB time were associated with a significant increase in the risk of mortality after urgent CABG.

“What’s the Risk?” Assessing and Mitigating Risk in Cardiothoracic Surgery

“What’s the Risk?” Assessing and Mitigating Risk in Cardiothoracic Surgery

Preoperative atrial fibrillation is an independent predictor of worse early and late outcomes after isolated coronary artery bypass graft surgery

ObjectivesTo evaluate the impact of preoperative atrial fibrillation (pre-op AF) on early and late mortality after isolated coronary artery bypass graft (CABG) surgery. MethodsData obtained prospectively between June 2001 and December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program were retrospectively analyzed. Patients who underwent concomitant atrial arrhythmia surgery/ablation were excluded. Demographic and operative data were compared between patients with and without pre-op AF. The independent association of pre-op AF on early mortality, perioperative complications, and late mortality was determined. ResultsIsolated CABG surgery was performed in 21,534 patients; 1312 (6.1%) presented with pre-op AF. Pre-op AF patients were older (mean age, 71 years vs. 65 years, p<0.001) and had more comorbidities reflected in a higher additive EuroSCORE (8.4±3.5 vs. 6.5±3.2, p=0.001). Even after accounting for confounding factors, however, pre-op AF was associated with a 63% increase in 30-day mortality [4.2% vs. 1.4%; hazard ratio (HR), 1.63; 95% confidence interval (CI), 1.17–2.29; p=0.004] and 39% increase in late mortality (5-year survival, 78% vs. 90%; HR, 1.39; 95% CI, 1.20–1.61; p<0.001). ConclusionPre-op AF is an independent predictor of poor early and late outcomes. Pre-op AF should be considered, therefore, in the development or update of risk stratification models for CABG surgery.

A propensity-score matched analysis on the impact of postoperative atrial fibrillation on the early and late outcomes after concomitant aortic valve replacement and coronary artery bypass graft surgery

Postoperative atrial fibrillation (POAF) is a known complication of cardiac surgery. There is a paucity of data on the effects of POAF on short-term and long-term outcomes after concomitant aortic valve replacement and coronary artery bypass grafting (AVR-CABG ). We retrospectively reviewed data on patients without preexisting arrhythmia who underwent isolated first-time AVR-CABG between June 2001 and December 2009 using the Australasian Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program. Preoperative characteristics, early postoperative outcomes and late survival were compared between patients who developed POAF and those who did not. Propensity score matching was performed to account for the differences between the two groups. Isolated AVR-CABG surgery was performed in 2028 patients without preexisting arrhythmias at 18 Australian institutions, of whom 894 (44.1%) developed POAF. POAF patients were generally older (mean age, 75 vs. 73 years, P < 0.001). From the initial study population, 715 propensity-matched patient-pairs were derived; the overall matching rate was 80.0%. In the matched groups, 30-day mortality was similar in both groups (3.5 vs. 2.1%, P = 0.16). Patients with POAF, however, were more likely to develop perioperative complications, including new renal failure, prolonged ventilation (>24 h), multisystem failure and readmission within 30 days of surgery (all P < 0.05). Patients with POAF also had a significantly greater length of hospital stay (P < 0.001). Seven-year survival was not significantly different between the two groups (72 vs. 75%, P = 0.11). POAF was not associated with an increased risk of early or late mortality. It is, however, associated with poorer perioperative outcomes. It is important to evaluate potential treatment strategies for POAF.

Impact of Smoking Status on Outcomes after Concomitant Aortic Valve Replacement and Coronary Artery Bypass Graft Surgery

There is a paucity of data on the impact of smoking status on outcomes after concomitant aortic valve replacement and coronary artery bypass graft (AVR-CABG) surgery. Data obtained prospectively between June 2001 and December 2009 by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program were retrospectively analyzed. Demographic and operative data were compared between patients who were nonsmokers, previous smokers, and current smokers using chi-square test and t-test. The independent impact of smoking status on 14 short-term complications and long-term mortality was determined using binary logistic and Cox regression, respectively. Concomitant AVR-CABG surgery was performed in 2,563 patients; smoking status was recorded in 2,558 (99.8%) patients. Of these, 1,052 (41.1%) patients had no previous smoking history, 1,345 (52.6%) patients were previous smokers, and 161 (6.3%) patients were current smokers. The 30-day mortality rate was 3.5% in nonsmokers, 4.1% in previous smokers, and 3.1% in current smokers (p = nonsignificant). The incidence of perioperative complications was similar in the three groups. The mean follow-up period for this study was 36 months (range, 0-105 months). After adjusting for differences in patient variables, the incidence of late mortality was higher in previous smokers (hazard ratio [HR], 1.44; 95% confidence interval [CI], 1.14-1.81; p = 0.002) compared with nonsmokers. A trend toward increased late mortality in current smokers was noted (HR, 1.34; 95% CI, 0.86-2.08; p = 0.201). Smoking is not associated with adverse outcomes after concomitant AVR-CABG surgery. Smoking status should not, therefore, preclude these patients from undergoing this procedure. Given the adverse effect of smoking on overall cardiovascular morbidity and mortality and late postoperative mortality, patients should be encouraged to quit smoking.

Preoperative atrial fibrillation is an independent risk factor for mid-term mortality after concomitant aortic valve replacement and coronary artery bypass graft surgery

Preoperative atrial fibrillation (PAF) has been associated with poorer early and mid-term outcomes after isolated valvular or coronary artery bypass graft surgery. Few studies, however, have evaluated the impact of PAF on early and mid-term outcomes after concomitant aortic valve replacement and coronary aortic bypass graft (AVR-CABG) surgery. Data obtained prospectively between June 2001 and December 2009 by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program was retrospectively analysed. Patients who underwent concomitant atrial arrhythmia surgery/ablation were excluded. Demographic and operative data were compared between patients undergoing concomitant AVR-CABG who presented with PAF and those who did not using chi-square and t-tests. The independent impact of PAF on 12 short-term complications and mid-term mortality was determined using binary logistic and Cox regression, respectively. Concomitant AVR-CABG surgery was performed in 2563 patients; 322 (12.6%) presented with PAF. PAF patients were generally older (mean age 76 vs 74 years; P < 0.001) and presented more often with comorbidities including congestive heart failure, chronic pulmonary disease and cerebrovascular disease (all P < 0.05). PAF was associated with 30-day mortality on univariate analysis (P = 0.019) but not multivariate analysis (P = 0.53). The incidence of early complications was not significantly higher in the PAF group. PAF was independently associated with reduced mid-term survival (HR, 1.58; 95% CI, 1.14-2.19; P = 0.006). PAF is associated with reduced mid-term survival after concomitant AVR-CABG surgery. Patients with PAF undergoing AVR-CABG should be considered for a concomitant surgical ablation procedure.

Postoperative Atrial Fibrillation After Isolated Aortic Valve Replacement: A Cause for Concern?

Several studies have shown that postoperative atrial fibrillation (POAF) is associated with poorer short-term and long-term outcomes after general cardiac operations. There is, however, a paucity of data on the impact of POAF on outcomes after isolated aortic valve replacement (AVR). Data for all patients undergoing isolated first-time AVR between June 2001 and December 2009 was obtained from the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) National Cardiac Surgery Database Program and a retrospective analysis was conducted. Preoperative characteristics, early postoperative outcome, and late survival were compared between patients in whom POAF developed and those in whom it did not. Propensity score matching was performed to correct for differences between the 2 groups. Excluding patients with preoperative arrhythmia, isolated first-time AVR was performed in 2,065 patients. POAF developed in 725 (35.1%) of them. Patients with POAF were significantly older (mean age, 72 versus 65 years; p < 0.001) and presented more often with comorbidities, including hypertension, respiratory disease, and hypercholesterolemia (all p < 0.05). From the initial study population, 592 propensity-matched patient pairs were derived; the overall matching rate was 81.7%. In the matched groups, 30-day mortality was not significantly different between the POAF and non-POAF groups (1.5% versus 1%; p = 0.48). Patients with POAF were, however, at an independently increased risk of perioperative complications, including new renal failure, gastrointestinal complications, and 30-day readmission (p < 0.05). Seven-year mortality was not significantly different between POAF and non-POAF groups (78% versus 83%; p = 0.63). POAF is a risk factor for short-term morbidity but is not associated with a higher rate of early or late mortality after isolated AVR.

Does Preoperative Atrial Fibrillation Portend a Poorer Prognosis in Patients Undergoing Isolated Aortic Valve Replacement? A Multicentre Australian Study

BackgroundPreoperative atrial fibrillation (preop-AF) has been associated with poorer early and late outcomes after cardiac surgery. Few studies, however, have evaluated the impact of preop-AF on early and late outcomes after isolated aortic valve replacement (AVR). MethodsData obtained prospectively between June 2001 and December 2009 by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program was retrospectively analyzed. Patients who underwent concomitant atrial arrhythmia surgery/ablation were excluded. Demographic and operative data were compared between patients undergoing isolated AVR who presented with preop-AF and those in sinus rhythm. The independent effect of preop-AF on 12 short-term complications and long-term survival was determined using binary logistic and cox regression, respectively. ResultsIsolated AVR surgery was performed in 2789 patients; 380 (13.6%) presented with preop-AF. Preop-AF patients were generally older (mean age, 73 vs 68 years; P < 0.001) and presented more often with comorbidities including congestive heart failure, diabetes, and cerebrovascular disease (all P < 0.05). There was a trend toward increased 30-day mortality in patients with preop-AF on multivariate analysis (P = 0.051). The incidence of early complications was similar in both groups on multivariate analysis (P > 0.05). Preop-AF was independently associated with reduced long-term survival (hazard ratio, 1.36; 95% confidence interval, 1.01-1.83; P = 0.041). ConclusionsPreop-AF is associated with an increased risk of late mortality after isolated AVR. As such, concomitant atrial ablation with AVR should be prospectively studied.

Usefulness of Postoperative Atrial Fibrillation as an Independent Predictor for Worse Early and Late Outcomes After Isolated Coronary Artery Bypass Grafting (Multicenter Australian Study of 19,497 Patients)

Several studies have shown that postoperative atrial fibrillation (POAF) is associated with poorer short- and long-term outcomes after isolated coronary artery bypass grafting surgery. Nevertheless, there is considerable debate as to whether this reflects an independent association of POAF with poorer outcomes or confounding by other factors. We sought to investigate this issue. Data obtained from June 2001 through December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program were retrospectively analyzed. Demographic and operative data were compared between patients who developed POAF and those who did not using chi-square and t tests. The independent impact of POAF on 14 short-term complications and long-term mortality was determined using binary logistic and Cox regression, respectively. Excluding patients with preoperative arrhythmia, isolated coronary artery bypass grafting surgery was performed in 19,497 patients. Of these, 5,547 (28.5%) developed POAF. Patients with POAF were generally older (mean age 69 vs 65 years, p <0.001) and presented more often with co-morbidities including congestive heart failure (p <0.001), hypertension (p <0.001), cerebrovascular disease (p <0.001), and renal failure (p = 0.046). Patients with POAF demonstrated a greater 30-day mortality on univariate analysis but not on multivariate analysis (p = 0.376). Patients with POAF were, however, at an independently increased risk of perioperative complications including permanent stroke (p <0.001), new renal failure (p <0.001), infective complications (p <0.001), gastrointestinal complications (p <0.001), and return to the theater (p <0.001). POAF was also independently associated with shorter long-term survival (p = 0.002). In conclusion, POAF is a risk factor for short-term morbidity and decreased long-term survival. Rigorous evaluation of various therapies that prevent or decrease the impact of POAF is imperative. Moreover, patients who develop POAF should undergo strict surveillance and be routinely screened for complications after discharge.

Early and late outcomes after isolated aortic valve replacement in octogenarians: an Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database Study

The advent of percutaneous aortic valve implantation has increased interest in the outcomes of conventional aortic valve replacement in elderly patients. The current study critically evaluates the short-term and long-term outcomes of elderly (≥80 years) Australian patients undergoing isolated aortic valve replacement. Data obtained prospectively between June 2001 and December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program were retrospectively analysed. Isolated aortic valve replacement was performed in 2791 patients; of these, 531 (19%) were at least 80 years old (group 1). The patient characteristics, morbidity and short-term mortality of these patients were compared with those of patients who were <80 years old (group 2). The long-term outcomes in elderly patients were compared with the age-adjusted Australian population. Group 1 patients were more likely to be female (58.6% vs 38.0%, p<0.001) and presented more often with co-morbidities including hypertension, cerebrovascular disease and peripheral vascular disease (all p<0.05). The 30-day mortality rate was not independently higher in group 1 patients (4.0% vs 2.0%, p=0.144). Group 1 patients had an independently increased risk of complications including new renal failure (11.7% vs 4.2%, p<0.001), prolonged (≥24 h) ventilation (12.4% vs 7.2%, p=0.003), gastrointestinal complications (3.0% vs 1.3%, p=0.012) and had a longer mean length of intensive care unit stay (64 h vs 47 h, p<0.001). The 5-year survival post-aortic valve replacement was 72%, which is comparable to that of the age-matched Australian population. Conventional aortic valve replacement in elderly patients achieves excellent outcomes with long-term survival comparable to that of an age-adjusted Australian population. In an era of percutaneous aortic valve implantation, it should still be regarded as the gold standard in the management of aortic stenosis.

Provider‐Hospital “Fit” and Patient Outcomes: Evidence from Massachusetts Cardiac Surgeons, 2002–2004

To examine whether the "fit" of a surgeon with hospital resources impacts cardiac surgery outcomes, separately from hospital or surgeon effects. Retrospective secondary data from the Massachusetts Department of Public Health's Data Analysis Center, on all 12,983 adult isolated coronary artery bypass surgical admissions in state-regulated hospitals from 2002 through 2004. Clinically audited chart data was collected using Society of Thoracic Surgeons National Cardiac Surgery Database tools and cross-referenced with administrative discharge data in the Division of Health Care Finance and Policy. Mortality was followed up through 2007 via the state vital statistics registry. Analysis was at the patient level for those receiving isolated coronary artery bypass surgery (CABG). Sixteen outcomes included 30-day mortality, major morbidity, indicators of perioperative, and predischarge processes of care. Hierarchical crossed mixed models were used to estimate fixed covariate and random effects at hospital, surgeon, and hospital × surgeon level. Hospital volume was associated with significantly reduced intraoperative durations and significantly increased probability of aspirin, β-blocker, and lipid-lowering discharge medication use. The proportion of outcome variability due to unobserved hospital × surgeon interaction effects was small but meaningful for intraoperative practices, discharge destination, and medication use. For readmissions and mortality within 30 days or 1 year, unobserved patient and hospital factors drove almost all variability in outcomes. Among Massachusetts patients receiving isolated CABG, consistent evidence was found that the hospital × surgeon combination independently impacted patient outcomes, beyond hospital or surgeon effects. Such distinct local interactions between a surgeon and hospital resources may play an important part in moderating quality improvement efforts, although residual patient-level factors generally contributed the most to outcome variability.

Trends in Emergency Coronary Artery Bypass Grafting After Percutaneous Coronary Intervention, 1994–2003

In the last decade, percutaneous coronary intervention (PCI) has undergone profound changes in techniques used to achieve revascularization and in patient selection. We examine trends in emergency surgical revascularization after PCI. Using The Society of Thoracic Surgeons National Cardiac Surgery Database, we examined patients undergoing coronary artery bypass grafting within 6 hours of PCI from 1994 to 2003. Stratifying into groups of patients who had and had not suffered myocardial infarction within 24 hours of PCI followed by coronary artery bypass grafting (CABG), we tracked trends in characteristics, predicted risk, and clinical outcomes. The proportion of isolated CABG procedures done emergently after PCI decreased over 1994 to 1999 from 3,357 of 115,679 (2.9%) to 1,227 of 155,831 (0.8%), remaining stable through 2003. Those suffering myocardial infarction within 24 hours made up a constant proportion of isolated CABG as emergency after PCI (3,352 of 1,042,864; 0.3%) since 1997. Over the decade, the preoperative risk profile worsened, including more elderly patients and more with cerebrovascular disease and congestive heart failure. Operative mortality among these patients has risen with time (from 8.0% to 9.3%; p < 0.0001 for trend), particularly in the setting of acute myocardial infarction (from 14.1% to 16.6%; p < 0.0001 for trend). Similarly, postoperative complications have increased over time, most notably seen in the need for reoperation (10.62% to 24.56%), prolonged postoperative ventilation (25.65% to 54.58%), and renal failure (10.22% to 18.55%). In 2005, there remains a low but real need for emergent CABG after PCI, in which operative outcomes are less than ideal, especially in the postinfarction patient, representing an area for cross-specialty collaboration.

Prediction of operative mortality after valve replacement surgery

OBJECTIVESWe sought to develop national benchmarks for valve replacement surgery by developing statistical risk models of operative mortality.BACKGROUNDNational risk models for coronary artery bypass graft surgery (CABG) have gained widespread acceptance, but there are no similar models for valve replacement surgery.METHODSThe Society of Thoracic Surgeons National Cardiac Surgery Database was used to identify risk factors associated with valve surgery from 1994 through 1997. The population was drawn from 49,073 patients undergoing isolated aortic valve replacement (AVR) or mitral valve replacement (MVR) and from 43,463 patients undergoing CABG combined with AVR or MVR. Two multivariable risk models were developed: one for isolated AVR or MVR and one for CABG plus AVR or CABG plus MVR.RESULTSOperative mortality rates for AVR, MVR, combined CABG/AVR and combined CABG/MVR were 4.00%, 6.04%, 6.80% and 13.29%, respectively. The strongest independent risk factors were emergency/salvage procedures, recent infarction, reoperations and renal failure. The c-indexes were 0.77 and 0.74 for the isolated valve replacement and combined CABG/valve replacement models, respectively. These models retained their predictive accuracy when applied to a prospective patient population undergoing operation from 1998 to 1999. The Hosmer-Lemeshow goodness-of-fit statistic was 10.6 (p = 0.225) for the isolated valve replacement model and 12.2 (p = 0.141) for the CABG/valve replacement model.CONCLUSIONSStatistical models have been developed to accurately predict operative mortality after valve replacement surgery. These models can be used to enhance quality by providing a national benchmark for valve replacement surgery.

Mortality after aortic valve replacement: results from a nationally representative database

Background. Nationally representative estimates of in-hospital mortality after aortic valve replacement are needed to evaluate whether results from The Society of Thoracic Surgeons National Cardiac Surgery Database are applicable to other institutions in the United States performing these procedures. Methods. Data from the 1994 Nationwide Inpatient Sample were used to estimate the patient characteristics and in-hospital mortality rates associated with aortic valve replacements performed in nonfederal hospitals in the United States. Procedural and hospital characteristics were examined for possible associations with in-hospital mortality. Results. An estimated 46,397 aortic valve replacements were performed. In-hospital mortality occurred in 4.3% of first-time isolated aortic valve replacements and 6.4% overall. The highest quartile of procedure-specific hospital volume, compared with the lowest quartile, was associated with lower in-hospital mortality (adjusted odds ratio, 0.58; 95% confidence interval, 0.42 to 0.81). Conclusions. The in-hospital mortality rates observed in this study are very similar to those reported from The Society of Thoracic Surgeons database. These data provide substantial evidence that results from The Society of Thoracic Surgeons database are representative of those achieved at other institutions. However, procedure-specific hospital volume must be considered in applying these results to individual institutions.

Is low ejection fraction safe for off-pump coronary bypass operation?

Background. Does the manipulation of the heart during off-pump coronary artery bypass (OPCAB) procedure further compromise the hemodynamic stability of a patient with depressed left ventricular function compared with the conventional coronary artery bypass (CCAB) approach? Does this manipulation induce a more dramatic hypoperfused state that may contribute to an increase in the incidence of related complications or mortality? This retrospective review of data attempted to answer the above concern. Methods. Between January 1, 1998, and June 30, 1999, 177 patients with ejection fractions of 30% or less underwent full sternotomy coronary artery bypass grafting at our institution. Of these patients, 45 underwent OPCAB procedures and 132 patients underwent CCAB. Pre-, intra-, and postoperative variables as identified by The Society of Thoracic Surgeons National Cardiac Surgery Database were compared using univariate and logistical regression analysis. Results. Despite recognized hemodynamic derangement during cardiac displacement, these groups of OPCAB patients appeared to tolerate the procedure well. Univariate analysis of cardiac enzyme leak and blood loss was statistically significant in the OPCAB patients. Utilizing regression analysis, cardiopulmonary bypass was the only predictor for all postoperative complications. Conclusions. Multivessel coronary artery bypass utilizing the OPCAB approach in patients with depressed left ventricular function of equal to or less than 30% is appropriate and applicable. Analysis of CCAB and OPCAB variables was nonsignificant except for operative and postoperative blood loss and peak cardiac enzyme leak. Attention to intraoperative detail and hemodynamic management could be credited for the success with OPCAB.

Safety and efficacy of off-pump coronary artery bypass grafting

Background. We evaluated the application of the off-pump coronary artery bypass (OPCAB) procedure relative to safety and efficiency as measured by operative mortality postoperative complications and longitudinal outcome.Methods. Three hundred and fifty OPCAB patients were compared to 3,171 on-pump or conventional coronary artery bypass (CCAB) patients between January 1, 1997 and December 31, 1998. The groups were divided into three preoperative predicted risk categories: low-risk (0 to 2.59%), medium-risk (2.6 to 9.9%), and high-risk (≥10%). Society of Thoracic Surgeons National Cardiac Surgery Database definitions and predicted risk group models were utilized to compare all preoperative, intraoperative, and postoperative variables using univariate analysis.Results. Overall comparison of the immediate outcome of CCAB and OPCAB shows little statistical significance in the variables analyzed. The operative mortality was 3.4% in both groups. When the immediate outcome was compared between groups (CCAB vs OPCAB), as well as individual risk groups (low, medium, and high), similar patterns of operative variables and postoperative complications were observed. The operative mortality in the low-risk group was 1.1% for CCAB and 1.4% for OPCAB; 7% for CCAB and 6% for OPCAB in the medium-risk group; and in the high-risk group 28.5% for CCAB compared to 7.7% for OPCAB group (p = 0.008). Short-term follow-up shows a trend of increased recurring angina and reinterventional procedures in the OPCAB patients.Conclusions. Safety for OPCAB is assessed through retrospective data review. Longitudinal follow-up for survival, reintervention, and quality of postoperative document efficacy and patency rates, compared to on-pump procedures, is mandatory. This study documented the immediate safety of the OPCAB procedure. Preliminary findings at 1-year follow-up is an important finding in this study, but it is not conclusive at this time. Long-term longitudinal follow-up is required to assess the future effectiveness of OPCAB.