The 1996 coronary artery bypass risk model: the Society of Thoracic Surgeons Adult Cardiac National Database

Early and Long-Term Outcomes of Transcatheter Aortic Valve Replacement for Selected Nonagenarians in Japan

BACKGROUND

Transcatheter aortic valve implantation (TAVI) is increasingly being performed in very elderly patients, although its efficacy and validity remain unclear. This study evaluated real-world TAVI outcomes in Japanese nonagenarians with severe aortic stenosis.Methods and Results:This single-center study retrospectively assessed the early and long-term clinical outcomes of TAVI in nonagenarians (n=35) and in patients aged <90 years (group Y; n=171). There were no in-hospital deaths in either group. The device success rate and early safety were comparable between the 2 groups. The 5-year rates of freedom from cardiac events and deaths were equivalent in both groups. The cumulative survival rate at 5 years was non-significantly lower in nonagenarians (32.6% in nonagenarians vs. 57.5% in patients aged <90 years, P=0.49). There were no differences in the 5-year survival between nonagenarians after TAVI and the sex- and age-matched populations (P=0.18). The Cox regression model revealed that lower hemoglobin levels were associated with all-cause mortality (P=0.02), and age ≥90 years was not associated with all-cause mortality.

CONCLUSIONS

The early and long-term clinical outcomes of TAVI for selected Japanese nonagenarians were comparable to those in patients aged <90 years. Nonagenarians who underwent TAVI achieved an acceptable prognosis compared to the sex- and age-matched population; thus, TAVI appears to be effective for treating aortic stenosis in Japanese nonagenarians.

Very low-dose recombinant Factor VIIa administration for cardiac surgical bleeding reduces red blood cell transfusions and renal risk: a matched cohort study

Outcomes following administration of very-low-dose recombinant activated factor VIIa (vld-rFVIIa) for cardiac surgical bleeding remain debatable. We sought to determine the association of vld-rFVIIa and adverse surgical outcomes. Retrospective, cohort matching of patients undergoing cardiac surgery who received vld-rFVIIa (median 13.02 μg/kg) for perioperative bleeding were matched to cardiac surgical patients who had bleeding and received standard of care for bleeding without Factor VIIa administration. Of the 362 matched patients (182 in each group), patients who received rFVIIa required significantly less red blood cell transfusions [median 3 units (range 0--60, IQR = 4 units) versus 4 units (range 2-34, IQR = 4 units); P = 0.0004], decreased length of hospital stay (median 8 versus 9 days; P = 0.0158) and decreased renal risk (P < 0.0001). Incidence of renal failure, postoperative infection, postoperative thrombosis, prolonged ventilation, total ICU hours and 30-day mortality were not different between the two groups. Vld-rFVIIa for cardiac surgical bleeding was associated with decreased red blood cell transfusion, renal risk and length of hospital stay without increased thromboembolism or mortality when compared to patients who had cardiac surgical bleeding and received standard of care without Factor VIIa.

Impact of aortic valve disease on outcomes of aortic root replacement

BACKGROUND AND AIM OF THE STUDY

Aortic stenosis (AS) has been associated with higher mortality in patients undergoing aortic root replacement (ARR). In this analysis, we compare the outcomes among patients with moderate to severe AS or aortic insufficiency (AI) undergoing ARR in a tertiary aortic center.

METHODS

A total of 889 patients underwent ARR from 1997 to 2020, of whom 798 had AI and 91 had AS. We excluded valve-sparing procedures. The primary endpoint consisted of major adverse events (MAEs), including operative mortality, myocardial infarction, tracheostomy, new dialysis, and cerebrovascular accidents. All patients had either a mechanical or biologic composite valve-graft implanted using button and exclusion techniques. Propensity score matching (PSM) was used to compare outcomes. Long-term survival was estimated using the Kaplan-Meier method.

RESULTS

Patients with AI had a higher incidence of connective tissue disorder (8.0% vs. 0.0%; p = .01) and were more likely to be classified as having an urgent or emergent procedure (22.4% vs. 8.8%; p = .004). PSM achieved a good balance between the groups. There was no difference in MAE rates, postoperatively (AI vs. AS, 1.6% vs. 1.6%; p = .85). Long-term survival was similar at 5 years in the matched cohorts (AI vs. AS, 75.9% vs. 95.5%; p = .36).

CONCLUSION

In patients undergoing ARR, the presence of moderate to severe AI or AS does not impact operative outcomes. ARR can be carried out with excellent outcomes and low operative mortality when performed in specialized centers.

Physical Performance and Risk of Postoperative Delirium in Older Adults Undergoing Aortic Valve Replacement

Background

Delirium is a major risk factor for poor recovery after surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR). It is unclear whether preoperative physical performance tests improve delirium prediction.

Objective

To examine whether physical performance tests can predict delirium after SAVR and TAVR, and adapt an existing delirium prediction rule for cardiac surgery, which includes Mini-Mental State Examination (MMSE), depression, prior stroke, and albumin level.

Design

Prospective cohort, 2014-2017.

Setting

Single academic center.

Subjects

A total of 187 patients undergoing SAVR (n=77) or TAVR (n=110).

Methods

The Short Physical Performance Battery (SPPB) score was calculated based on gait speed, balance, and chair stands (range: 0-12 points, lower scores indicate poor performance). Delirium was assessed using the Confusion Assessment Method. We fitted logistic regression to predict delirium using SPPB components and risk factors of delirium.

Results

Delirium occurred in 35.8% (50.7% in SAVR and 25.5% in TAVR). The risk of delirium increased for lower SPPB scores: 10-12 (28.2%), 7-9 (34.5%), 4-6 (37.5%) and 0-3 (44.1%) (p-for-trend=0.001). A model that included gait speed <0.46 meter/second (OR, 2.7; 95% CI, 1.2-6.4), chair stands time ≥11.2 seconds (OR, 3.5; 95% CI, 1.0-12.4), MMSE <24 points (OR, 2.9; 95% CI, 1.3-6.4), isolated SAVR (OR, 5.4; 95% CI, 2.1-13.8), and SAVR and coronary artery bypass grafting (OR, 15.8; 95% CI, 5.5-45.7) predicted delirium better than the existing prediction rule (C statistics: 0.71 vs 0.61; p=0.035).

Conclusion

Assessing physical performance, in addition to cognitive function, can help identify high-risk patients for delirium after SAVR and TAVR.

Risk Stratification for Transcatheter Aortic Valve Replacement

Risk assessment models developed from administrative and clinical databases are used for clinical decision making. Since these models are derived from a database, they have an inherent limitation of being as good as the data they are derived from. Many of these models under or overestimate certain clinical outcomes particularly mortality in certain group of patients. Undeniably, there is significant variability in all these models on account of patient population studied, the statistical analysis used to develop the model and the period during which these models were developed. This review aims to shed light on development and application of risk assessment models for cardiac surgery with special emphasis on risk stratification in severe aortic stenosis to select patients for transcatheter aortic valve replacement.

Minimally Invasive Sutureless Aortic Valve Replacement is Associated With Improved Outcomes in Patients With Left Ventricular Dysfunction

Objective

Patients with severe aortic stenosis and reduced left ventricular ejection fraction (LVEF) have a poor prognosis compared with patients with preserved LVEF. To evaluate the impact of sutureless Perceval (LivaNova, Italy) aortic bioprosthesis on LVEF and clinical outcomes in patients with baseline left ventricular (LV) dysfunction who underwent isolated aortic valve replacement (AVR).

Methods

Between March 2011 and August 2017, 803 patients underwent AVR with Perceval bioprosthesis implantation. Fifty-two isolated AVR had preoperative LVEF ≤45%. Mean age of these patients was 77 ± 6 years, 24 patients were female (46%), and mean EuroSCORE II was 9.4% ± 4.8%. Perceval bioprosthesis was implanted in 9 REDO operations. In 43 patients (83%), AVR was performed in minimally invasive surgery with an upper ministernotomy ( n = 13) or right anterior minithoracotomy ( n = 30).

Results

One patient died in hospital. Cardiopulmonary bypass and aortic cross-clamp times were 85.5 ± 26 minutes and 55.5 ± 19 minutes, respectively. At mean follow-up of 33 ± 20 months (range: 1 to 75 months), survival was 90%, freedom from reoperation was 100%, and mean transvalvular pressure gradient was 11 ± 5 mmHg. LVEF improved from 37% ± 7% preoperatively to 43% ± 8% at discharge ( P < 0.01) and further increased to 47% ± 9% at follow-up ( P = 0.06), LV mass decreased from 149.8 ± 16.9 g/m2 preoperatively to 115.3 ± 11.6 g/m2 at follow-up ( P < 0.001), and moderate paravalvular leakage occurred in 1 patient without hemolysis not requiring any treatment.

Conclusions

AVR with sutureless aortic bioprosthesis implantation in patients with preoperative LV dysfunction demonstrated a significant immediate and early improvement in LVEF.

Modifying risks to improve outcome in cardiac surgery: An anesthesiologist's perspective

Challenging times are here for cardiac surgical and anesthesia team. The interventional cardiologist seem to have closed the flow of ‘good cases’ coming up for any of the surgery,; successful percutaneous interventions seem to be offering reasonable results in these patients, who therefore do not knock on the doors of the surgeons any more. It is a common experience among the cardiac anesthesiologists and surgeons that the type of the cases that come by now are high risk. That may be presence of comorbidities, ongoing medical therapies, unstable angina, uncontrolled heart failure and rhythm disturbances; and in patients with ischemic heart disease, the target coronaries are far from ideal. Several activities such as institution of preoperative supportive circulatory, ventilatory, and systemic disease control maneuvers seem to have helped improving the outcome of these ‘high risk ‘ patients. This review attempts to look at various interventions and the resulting improvement in outcomes. Several changes have happened in the realm of cardiac surgery and several more are en route. At times, for want of evidence, maximal optimization may not take place and the patient may encounter unfavorable outcomes.. This review is an attempt to bring the focus of the members of the cardiac surgical team on the value of preoperative optimization of risks to improve the outcome. The cardiac surgical patients may broadly be divided into adults undergoing coronary artery bypass graft surgery, valve surgery and pediatric patients undergoing repair/palliation of congenital heart ailments. Optimization of risks appear to be different in each genre of patients. This review also brings less often discussed issues such as anemia, nutritional issues and endocrine problems. The review is an attempt to data on ameliorating modifiable risk factors and altering non modifiable ones.

Creation and Validation of an Automated Algorithm to Determine Postoperative Ventilator Requirements After Cardiac Surgery

BACKGROUND

In medical practice today, clinical data registries have become a powerful tool for measuring and driving quality improvement, especially among multicenter projects. Registries face the known problem of trying to create dependable and clear metrics from electronic medical records data, which are typically scattered and often based on unreliable data sources. The Society for Thoracic Surgery (STS) is one such example, and it supports manually collected data by trained clinical staff in an effort to obtain the highest-fidelity data possible. As a possible alternative, our team designed an algorithm to test the feasibility of producing computer-derived data for the case of postoperative mechanical ventilation hours. In this article, we study and compare the accuracy of algorithm-derived mechanical ventilation data with manual data extraction.

METHODS

We created a novel algorithm that is able to calculate mechanical ventilation duration for any postoperative patient using raw data from our EPIC electronic medical record. Utilizing nursing documentation of airway devices, documentation of lines, drains, and airways, and respiratory therapist ventilator settings, the algorithm produced results that were then validated against the STS registry. This enabled us to compare our algorithm results with data collected by human chart review. Any discrepancies were then resolved with manual calculation by a research team member.

RESULTS

The STS registry contained a total of 439 University of California Los Angeles cardiac cases from April 1, 2013, to March 31, 2014. After excluding 201 patients for not remaining intubated, tracheostomy use, or for having 2 surgeries on the same day, 238 cases met inclusion criteria. Comparing the postoperative ventilation durations between the 2 data sources resulted in 158 (66%) ventilation durations agreeing within 1 hour, indicating a probable correct value for both sources. Among the discrepant cases, the algorithm yielded results that were exclusively correct in 75 (93.8%) cases, whereas the STS results were exclusively correct once (1.3%). The remaining 4 cases had inconclusive results after manual review because of a prolonged documentation gap between mechanical and spontaneous ventilation. In these cases, STS and algorithm results were different from one another but were both within the transition timespan. This yields an overall accuracy of 99.6% (95% confidence interval, 98.7%-100%) for the algorithm when compared with 68.5% (95% confidence interval, 62.6%-74.4%) for the STS data (P < .001).

CONCLUSIONS

There is a significant appeal to having a computer algorithm capable of calculating metrics such as total ventilator times, especially because it is labor intensive and prone to human error. By incorporating 3 different sources into our algorithm and by using preprogrammed clinical judgment to overcome common errors with data entry, our results proved to be more comprehensive and more accurate, and they required a fraction of the computation time compared with manual review.

Risk Evaluation and Midterm Outcome of Cardiac Surgery in Patients on Dialysis

The medical charts of 54 patients on maintenance dialysis who underwent cardiovascular surgery (37 elective and 17 urgent/emergency) from 1994 to 2004 were retrospectively analyzed. Thirty patients had coronary artery bypass grafting (17 elective and 13 urgent/emergency), 18 had valve replacement (16 elective and 2 urgent/emergency), and 6 underwent aortic surgery (4 elective and 2 urgent/emergency). The overall early mortality rate was 11.1%, comprising 2 patients (5.4%) who had elective operations and 4 (23.5%) who had urgent or emergency operations ( p = 0.049). The overall 5-year survival rate was 48.4%. The 5-year survival rate was 67.2% for elective surgery and 10.5% for urgent/emergency surgery ( p = 0.0001). The midterm clinical results after elective cardiovascular surgery were acceptable, whereas the results after urgent/emergency surgery were poor. For elective surgery, sufficient and detailed preoperative examinations might have contributed to the better operative outcome. Early diagnosis and consultation to avoid urgent/emergency operations in dialysis patients is recommended.

The Society of Thoracic Surgeons Adult Cardiac Surgery Database: The Driving Force for Improvement in Cardiac Surgery

Initiated in 1989, the Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (ACSD) includes more than 1085 participating centers, representing 90%-95% of current US-based adult cardiac surgery hospitals. Since its inception, the primary goal of the STS ACSD has been to use clinical data to track and improve cardiac surgical outcomes. Patients' preoperative risk characteristics, procedure-related processes of care, and clinical outcomes data have been captured and analyzed, with timely risk-adjusted feedback reports to participating providers. In 2006, STS initiated an external audit process to evaluate STS ACSD completeness and accuracy. Given the extremely high inter-rater reliability and completeness rates of STS ACSD, it is widely regarded as the "gold standard" for benchmarking cardiac surgery risk-adjusted outcomes. Over time, STS ACSD has expanded its quality horizons beyond the traditional focus on isolated, risk-adjusted short-term outcomes such as perioperative morbidity and mortality. New quality indicators have evolved including composite measures of key processes of care and outcomes (risk-adjusted morbidity and risk-adjusted mortality), longer-term outcomes, and readmissions. Resource use and patient-reported outcomes would be added in the future. These additional metrics provide a more comprehensive perspective on quality as well as additional end points. Widespread acceptance and use of STS ACSD has led to a cultural transformation within cardiac surgery by providing nationally benchmarked data for internal quality assessment, aiding data-driven quality improvement activities, serving as the basis for a voluntary public reporting program, advancing cardiac surgery care through STS ACSD-based research, and facilitating data-driven informed consent dialogues and alternative treatment-related discussions.

Risk Factors for Urinary Tract Infections in Cardiac Surgical Patients

BACKGROUND

Risk factors for catheter-associated urinary tract infections (CAUTIs) in patients undergoing non-cardiac surgical procedures have been well documented. However, the variables associated with CAUTIs in the cardiac surgical population have not been clearly defined. Therefore, the purpose of this study was to investigate risk factors associated with CAUTIs in patients undergoing cardiac procedures.

METHODS

All patients undergoing cardiac surgery at a single institution from 2006 through 2012 (4,883 patients) were reviewed. Patients with U.S. Centers for Disease Control (CDC) criteria for CAUTI were identified from the hospital's Quality Assessment database. Pre-operative, operative, and post-operative patient factors were evaluated. Univariate and multivariable analyses were used to identify significant correlations between perioperative characteristics and CAUTIs.

RESULTS

There were 55 (1.1%) documented CAUTIs in the study population. On univariate analysis, older age, female gender, diabetes mellitus, cardiogenic shock, urgent or emergent operation, packed red blood cell (PRBC) units transfused, and intensive care unit length of stay (ICU LOS) were all significantly associated with CAUTI [p<0.05]. On multivariable logistic regression, older age, female gender, diabetes mellitus, and ICU LOS remained significantly associated with CAUTI. Additionally, there was a significant association between CAUTI and 30-d mortality on univariate analysis. However, when controlling for common predictors of operative mortality on multivariable analysis, CAUTI was no longer associated with mortality.

CONCLUSIONS

There are several identifiable risk factors for CAUTI in patients undergoing cardiac procedures. CAUTI is not independently associated with increased mortality, but it does serve as a marker of sicker patients more likely to die from other comorbidities or complications. Therefore, awareness of the high-risk nature of these patients should lead to increased diligence and may help to improve peri-operative outcomes. Recognizing patients at high risk for CAUTI may lead to improved measures to decrease CAUTI rates within this population.

Left ventricular remodelling in aortic stenosis

Aortic stenosis (AS) is a progressive condition associated with high mortality if not treated. The hemodynamic effects of AS have serious implications for the left ventricle. In this review, we describe the responses of the left ventricle to AS by highlighting the process of adaptive remodelling, which begins as a beneficial compensatory mechanism but ultimately transitions to a maladaptive process with potentially irreversible consequences. We discuss the impact of left ventricular (LV) remodelling on diastolic and systolic function and on the development of symptoms. In addition, we review the adverse consequences of maladaptive LV remodelling on clinical outcomes before and after aortic valve replacement. The relative irreversibility of maladaptive remodelling and the clear relationship between its progression and clinical outcomes suggest a need to incorporate measures of LV performance beyond simply systolic function when deciding on the timing of valve replacement.

Myocardium at risk is associated with adverse clinical events in women but not in men, after coronary artery bypass grafting

BACKGROUND

Women undergoing coronary artery bypass grafting (CABG) are at increased risk for morbidity and mortality. Factors responsible for this observation include smaller coronary size and delayed presentation. To date, no studies have examined the effect of the degree of myocardium at risk (MAR) on the relationship between female sex and adverse postoperative events.

METHODS

Consecutive patients undergoing first-time isolated CABG at a single institution from 2002-2007 were identified. MAR was calculated using the weighted Duke Index and was categorized as low, moderate, or high. Multivariable logistic regression models were created to compare the impact of MAR on adverse clinical events.

RESULTS

We identified 3741 patients, 3325 (89%) of whom had complete angiographic data. Women (n = 755) were older (P = 0.0001) and presented more often with hypertension (P = 0.0001), diabetes (P = 0.0001), heart failure (P = 0.0001), and an urgent/emergent situation (P = 0.002). After surgery, women experienced greater rates of adverse events (15.2% vs 9.3%; P = 0.0001). In a fully adjusted logistic regression model, the nested interaction of sex in MAR showed that women had a significantly greater risk of major adverse cardiovascular events (MACE) when MAR was high (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.3-2.6; P = 0.0004). Greater severity of MAR emerged as an independent predictor of adverse events among women (high: OR, 2.9; 95% CI, 1.2-7.3; moderate: OR, 2.2; 95% CI, 0.8-5.7; low: OR, 1.0), but not among men.

CONCLUSIONS

MAR was independently associated with higher rates of adverse events among women but not in men undergoing CABG. This finding may help explain differences in outcomes seen between women and men after revascularization.

Outcomes of transcatheter and surgical aortic valve replacement in high-risk patients with aortic stenosis and left ventricular dysfunction: results from the Placement of Aortic Transcatheter Valves (PARTNER) trial (cohort A)

BACKGROUND

The Placement of Aortic Transcatheter Valves (PARTNER) trial demonstrated similar survival after transcatheter and surgical aortic valve replacement (TAVR and SAVR, respectively) in high-risk patients with symptomatic, severe aortic stenosis. The aim of this study was to evaluate the effect of left ventricular (LV) dysfunction on clinical outcomes after TAVR and SAVR and the impact of aortic valve replacement technique on LV function.

METHODS AND RESULTS

The PARTNER trial randomized high-risk patients with severe aortic stenosis to TAVR or SAVR. Patients were stratified by the presence of LV ejection fraction (LVEF) <50%. All-cause mortality was similar for TAVR and SAVR at 30-days and 1 year regardless of baseline LV function and valve replacement technique. In patients with LV dysfunction, mean LVEF increased from 35.7±8.5% to 48.6±11.3% (P<0.0001) 1 year after TAVR and from 38.0±8.0% to 50.1±10.8% after SAVR (P<0.0001). Higher baseline LVEF (odds ratio, 0.90 [95% confidence interval, 0.86, 0.95]; P<0.0001) and previous permanent pacemaker (odds ratio, 0.34 [95% confidence interval, 0.15, 0.81]) were independently associated with reduced likelihood of ≥10% absolute LVEF improvement by 30 days; higher mean aortic valve gradient was associated with increased odds of LVEF improvement (odds ratio, 1.04 per 1 mm Hg [95% confidence interval, 1.01, 1.08]). Failure to improve LVEF by 30 days was associated with adverse 1-year outcomes after TAVR but not SAVR.

CONCLUSIONS

In high-risk patients with severe aortic stenosis and LV dysfunction, mortality rates and LV functional recovery were comparable between valve replacement techniques. TAVR is a feasible alternative for patients with symptomatic severe aortic stenosis and LV dysfunction who are at high risk for SAVR.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00530894.

Risk-adjusted models for adverse obstetric outcomes and variation in risk-adjusted outcomes across hospitals

OBJECTIVE

Regulatory bodies and insurers evaluate hospital quality using obstetrical outcomes, however meaningful comparisons should take preexisting patient characteristics into account. Furthermore, if risk-adjusted outcomes are consistent within a hospital, fewer measures and resources would be needed to assess obstetrical quality. Our objective was to establish risk-adjusted models for 5 obstetric outcomes and assess hospital performance across these outcomes.

STUDY DESIGN

We studied a cohort of 115,502 women and their neonates born in 25 hospitals in the United States from March 2008 through February 2011. Hospitals were ranked according to their unadjusted and risk-adjusted frequency of venous thromboembolism, postpartum hemorrhage, peripartum infection, severe perineal laceration, and a composite neonatal adverse outcome. Correlations between hospital risk-adjusted outcome frequencies were assessed.

RESULTS

Venous thromboembolism occurred too infrequently (0.03%; 95% confidence interval [CI], 0.02-0.04%) for meaningful assessment. Other outcomes occurred frequently enough for assessment (postpartum hemorrhage, 2.29%; 95% CI, 2.20-2.38, peripartum infection, 5.06%; 95% CI, 4.93-5.19, severe perineal laceration at spontaneous vaginal delivery, 2.16%; 95% CI, 2.06-2.27, neonatal composite, 2.73%; 95% CI, 2.63-2.84). Although there was high concordance between unadjusted and adjusted hospital rankings, several individual hospitals had an adjusted rank that was substantially different (as much as 12 rank tiers) than their unadjusted rank. None of the correlations between hospital-adjusted outcome frequencies was significant. For example, the hospital with the lowest adjusted frequency of peripartum infection had the highest adjusted frequency of severe perineal laceration.

CONCLUSION

Evaluations based on a single risk-adjusted outcome cannot be generalized to overall hospital obstetric performance.

Nitroglycerin and sodium nitroprusside: potential contributors to postoperative bleeding?

Postoperative bleeding is common in patients undergoing cardiac surgery with cardiopulmonary bypass. Most cases of severe postoperative bleeding not due to incomplete surgical hemostasis are related to acquired transient platelet dysfunction mediated by platelet activation during contact with the synthetic surfaces of the cardiopulmonary bypass equipment. Antihypertensive agents nitroglycerin and sodium nitroprusside have been shown to have platelet inhibitory properties, yet the clinical consequence in terms of postoperative bleeding has been little studied. Knowing that cardiopulmonary bypass causes platelet dysfunction, it is prudent for physicians to be aware of the additional platelet inhibition caused by these commonly used antihypertensive agents.

Completeness of revascularization and survival among octogenarians with triple-vessel disease

BACKGROUND

We sought to determine the impact of the completeness of surgical revascularization among octogenarians with triple-vessel disease.

METHODS

Between 1992 and 2008, 476 consecutive patients aged 80 years or more who underwent primary isolated coronary artery bypass grafting (CABG) procedures were identified. Early and late survival were compared among patients who underwent complete revascularization (CR, n=391) and incomplete revascularization (IR, n=85). IR was present when 1 or more of the 3 main coronary arteries with 50% or greater stenosis that were identified preoperatively as a surgical target by the operating surgeon were not grafted. The mean follow-up was 5.4±3.0 years (maximum 15.3 years).

RESULTS

Baseline risk was similar between the 2 groups of patients. IR was more frequent in off-pump compared with on-pump CABG (34.9% versus 16.2%, respectively; p=0.002). The most common reason for IR was small or severely diseased arteries (87%). The incidence of postoperative myocardial infarction (MI) was similar in both groups (CR, 18.4% versus IR, 17.3%; p=0.81). In-hospital mortality was 7.2% among patients with CR and 4.7% among patients with IR (p=0.60). Three, 5-, and 8-year freedom from all-cause mortality among patients who underwent CR were 89.2%, 74.1%, and 54.3%, respectively, and were not significantly different from those patients who underwent IR (86.6%, 74.5%, and 49.4%, respectively) (p=0.40).

CONCLUSIONS

In octogenarians with triple-vessel disease, a strategy of incomplete revascularization during CABG does not negatively impact early or long-term survival.

Nitric oxide and the CABG patient

The post surgery success of coronary artery bypass grafting (CABG) is counteracted by thrombosis and de-endothelialization, intimal hyperplasia and, over the long term, atherosclerosis. There are many reasons to assume that in CABG patients vascular bioavailability of NO generated by the endothelium plays an important role for graft function. This holds true for factors such as graft type, harvesting and storage, the type of surgery, non-pharmacologic prevention of risk factors, for example, regular physical activity (if feasible), and drug therapy. Although the precise role of graft endothelial NO bioavailability for graft patency and clinical endpoints is still uncertain, current data rather speak in favor of NO indicating that the potential of vasoprotective activities of NO in the CABG patient deserves further investigation.

Cardiovascular surgery risk prediction from the patient's perspective

OBJECTIVE

Previous studies have developed cardiovascular surgery outcome prediction models using only patient risk factors, but surgery outcomes from the patient's perspective seem to differ between hospitals. We have developed outcome prediction models that incorporate preoperative patient risks, as well as hospital processes and structure.

METHODS

Data were collected from the Japan Cardiovascular Database for patients scheduled for cardiovascular surgery between January 2005 and December 2007. We analyzed 33,821 procedures in 102 hospitals. Logistic regression was used to generate risk models, which were then validated through split-sample validation.

RESULTS

Odds ratios, 95% confidence intervals, and P values for structures and processes in the mortality prediction model were as follows: "hospital annual adult cardiac surgery volume (continuous; every 1 procedure increase per year)" (odds ratio, 0.998; confidence interval, 0.997-0.999; P < .001); "recommended staffing and equipment" (odds ratio, 0.75; confidence interval, 0.64-0.87; P < .001); "daily conferences with cardiologists" (odds ratio, 0.79; confidence interval, 0.60-1.02; P = .073); "intensivists involved in postsurgical management" (odds ratio, 0.89; confidence interval, 0.77-1.02; P = .90); "public hospitals" (odds ratio, 0.80; confidence interval, 0.70-0.93; P = .003); "surgeons lacking miscellaneous duties" (odds ratio, 0.80; confidence interval, 0.70-0.93; P = .003); and "surgeons who work no more than 32 hours per week" (odds ratio, 0.55; confidence interval, 0.32-0.95; P = .032). The mortality prediction model had a C-index of 0.85 and a Hosmer-Lemeshow P value of .79.

CONCLUSIONS

Our models yielded good discrimination and calibration, so they may prove useful for hospital selection based on individual patient risks and circumstances. Improved surgeon work environments were also shown to be important for both surgeons and patients.

Is an intraaortic balloon pump a contraindication to robotic totally endoscopic coronary artery bypass?

BACKGROUND

The success of robotic totally endoscopic coronary artery bypass (TECAB) in recent years has led to the expansion of the procedure to patients with more severe disease. Outcomes with these patients have not yet been well characterized, and no reports on TECAB performed in patients with a preoperatively placed intraaortic balloon pump (IABP) are available. We present our initial experience with this patient population.

PATIENTS AND METHODS

We evaluated 5 patients with unstable angina or impaired left ventricular function requiring a preoperatively placed IABP who underwent TECAB using the daVinci telemanipulation system. Procedures were performed either on the beating heart using an endostabilizer (n = 2) or on the arrested heart using remote access perfusion and aortic balloon endoocclusion (n = 3). The median patient age was 67 years (range, 41-73 years), with a median preoperative ejection fraction of 43% (range, 26%-58%) and median EuroSCORE of 5 (range, 3-8).

RESULTS

There were no major intraoperative technical issues. The median length of stay in the hospital and intensive care unit was 8 days (range, 5-13 days) and 66 hours (range, 41-142 hours), respectively. There were no intraoperative or 30-day mortalities.

CONCLUSIONS

This early experience suggests that TECAB is feasible in patients with a preoperatively placed IABP. Both the beating heart and arrested heart versions can be used in this patient population, further broadening the spectrum of applicability of this procedure.

Using Society of Thoracic Surgeons risk models for risk-adjusting cardiac surgery results

The Society of Thoracic Surgeons National Adult Cardiac Surgery Database (STS NCD) has become the national benchmark for cardiac surgery reporting. Several important aspects of its risk-adjustment reporting are discussed, with special emphasis on using the reported individual STS risk scores for analysis and evaluation: (1) Different risk models are used in different STS NCD versions. (2) STS calibrates risk scores annually to make the annual predicted rates equal the observed rates. (3) The risk scores given by the STS, whether in the approved STS data collection software programs, published risk models, or online calculator, are not calibrated. (4) The end-user is required to calibrate the STS risk scores before using them. (5) After calibration, the STS predicted risk for any given patient is usually smaller, sometimes less than half of the uncalibrated value. (6) STS uses an observed/expected ratio method to calibrate the risk scores; for technical reasons, it is preferable to use an odds ratio method.

A short history of the Society of Thoracic Surgeons national cardiac database: perceptions of a practicing surgeon

The Society of Thoracic Surgeons database was developed as an initiative to standardize nationwide outcomes in adult cardiac surgery, and it has currently expanded into general thoracic and congenital cardiac surgery databases. For more than 19 years since its inception, the Society of Thoracic Surgeons database has grown as a powerful source of risk-adjusted outcomes, large scale scientific contributions, and invaluable information for healthcare policy making. This review article provides a snapshot of the genesis, history, growth, and scientific contributions of the Society of Thoracic Surgeons database to stimulate the participation of thoracic surgery programs and maximize its future use for investigational purposes.

Timing of nonemergent coronary artery bypass grafting and mortality after non-ST elevation acute coronary syndrome

BACKGROUND

The purpose of this study was to determine the association between time to coronary artery bypass grafting (CABG) and mortality among patients admitted with non-ST elevation acute coronary syndrome (NSTEACS). Patients are increasingly being referred for CABG soon after NSTEACS, although few data exist to guide the optimal timing of bypass surgery.

METHODS

We identified a cohort of all patients who underwent nonemergent CABG within 60 days of hospitalization for NSTEACS in the province of Alberta, Canada, from 2000 to 2004. Time from admission to CABG was categorized as early (2-7 days), intermediate (8-14 days), or late (15-60 days-reference group). The primary outcome was mortality occurring within 30 days of surgery.

RESULTS

Of the total cohort of 1,454 patients, 213 (14.6%) underwent early, 637 (43.8%) underwent intermediate, and 707 (48.6%) underwent late CABG surgery. In the final adjusted model time to CABG was not statistically significant as an independent predictor of short-term mortality. Compared to late CABG, there was a nonsignificant increased risk of mortality for those undergoing early (hazard ratio 2.36, 95% CI 0.72-7.76) and intermediate (hazard ratio 1.68, 95% CI 0.76-3.72) CABG surgery.

CONCLUSIONS

Time from admission to CABG was not associated with an increased risk of short-term mortality. However, there was a trend toward increased mortality with early CABG, and this study does not exclude the presence of a modest risk association between timing of CABG and short-term mortality.

The European System for Cardiac Operative Risk Evaluation (EuroSCORE) is not appropriate for withholding surgery in high-risk patients with aortic stenosis: a retrospective cohort study

BACKGROUND

The European System for Cardiac Operative Risk Evaluation (EuroSCORE) is a widely used risk assessment tool in patients with severe aortic stenosis to determine operability and to select patients for alternative therapies such as transcatheter aortic valve implantation. The objective of this study was to determine the accuracy of the EuroSCORE in predicting mortality following aortic valve replacement (AVR).

METHODS

The logistic EuroSCORE was determined for all consecutive patients that underwent conventional AVR between 1995 and 2005 at our institution. Provincial Vital Statistics were used to determine all-cause mortality. The accuracy of the prognostic risk prediction provided by logistic EuroSCORE was assessed by comparing observed and expected operative mortality.

RESULTS

During the study period, a total of 1,421 patients underwent AVR including 237 patients (16.7%) that had a logistic EuroSCORE > 20. Among these patients, the mean predicted operative mortality was 38.7% (SD = 18.1). The actual mortality of these patients was significantly lower than that predicted by EuroSCORE (11.4% vs. 38.7%, observed/expected ratio 0.29, 95% CI 0.15-0.52, P < 0.05). The EuroSCORE overestimated mortality within all strata of predicted risk. Although medium-term mortality is significantly higher among patients with EuroSCORE > 20 (log rank P = 0.0001), approximately 60% are alive at five years.

CONCLUSION

Actual operative mortality in patients undergoing AVR is significantly lower than that predicted by the logistic EuroSCORE. Additionally, medium-term survival following AVR is acceptable in high-risk patients with EuroSCORE > 20. More accurate risk prediction models are needed for risk-stratifying patients with severe aortic stenosis.

Prediction of survival after coronary revascularization: modeling short-term, mid-term, and long-term survival

BACKGROUND

Many clinical prediction rules for short-term mortality after coronary revascularization have been developed, validated, and introduced into routine clinical practice. Few rules exist for predicting long-term survival in the modern era of coronary revascularization. We report on the development and validation of models for predicting long-term survival after coronary artery bypass graft surgery and percutaneous coronary intervention on the basis of recent experience.

METHODS

We linked 1987 through 2001 coronary artery bypass graft surgery and 1992 through 2001 percutaneous coronary intervention data from our northern New England registries on 35,000 patients with complete data on risk factors to the National Death Index, ascertaining 7,000 deaths. We partitioned time after revascularization into three periods on the basis of exploratory analysis using generalizations of Cox's semiparametric model to nonproportional hazards and nonlinear log-hazards. These periods were 0 to 3 months, 4 to 18 months, and 19 months and later. For each period, Cox's regression model was used to regress survival on risk factors yielding three models, which were then combined to make long-term predictions.

RESULTS

These models were incorporated into easy-to-use software that yields predicted survival for up to 8 years after revascularization. The Harrell concordance statistic ranged from 72% to 83% for these models.

CONCLUSIONS

We developed and internally validated models that accurately predict long-term survival after coronary artery bypass graft surgery and percutaneous coronary intervention as currently performed. These models using routine clinical data, can be solved with available software, and could be used to enhance informed, patient-centered clinical decision making on the choice of revascularization procedure.

Factors affecting postoperative morbidity and mortality in isolated coronary artery bypass graft surgery

PURPOSE

This study was conducted to investigate predictors of mortality before and after isolated coronary artery bypass grafting (CABG).

METHODS

Single-institutional data on risk factors and mortality were collected for 8890 patients who underwent isolated CABG by the same group of surgeons. The relationship between risk factors and outcome was assessed using univariate and multivariate analyses in two risk models: a preoperative model (model 1) and then a pre-, intra-, and postoperative model (model 2).

RESULTS

The mean age of the patients (25.4% women and 74.6% men) was 58.5 +/- 9.7 years. Fifty-five (0.6%) patients died after surgery. Hypercholesterolemia was the most common comorbidity factor (61.1%), followed by hypertension, a smoking habit, recent myocardial infarction (MI) <21 days, and diabetes. Postoperative tamponade, graft occlusion, and MI (0.01%) were the least common complications. The patients spent 39.7 +/- 33.9 h in the intensive care unit (ICU) postoperatively. Patients were followed up for a minimum of 30 days. The multivariate analysis of our preoperative risk model revealed that the best predictors of operative mortality were a history of diabetes, hypertension, previous CABG, the presence of angina, arrhythmia, Canadian Cardiovascular Society Classification (CCS) of grade III or IV, ejection fraction (EF) < or =30%, three-vessel disease, and left main disease.

CONCLUSION

After surgery, and with the inclusion of all the pre-, intra-, and postoperative variables into model two, the following were revealed to be prognostic factors for in-hospital mortality: a history of diabetes, hypertension, the presence of angina, CCS grades III or IV, EF -30%, absence of internal mammary artery (IMA) use, prolonged cardiopulmonary bypass (CPB) time, and prolonged ICU stay.

Even moderate chronic renal failure is associated with impaired acute and long-term outcome after coronary angioplasty

End-stage renal failure requiring maintenance haemodialysis is known to be a strong independent predictor of mortality and complications after coronary interventions. In contrast, data about the outcome of patients with moderate chronic renal failure is very limited and was therefore evaluated in this study in patients with coronary angioplasty (PTCA). This was a retrospective case-control study of 66 patients with moderate chronic renal failure who underwent PTCA, and who were matched to 66 PTCA patients with normal renal function and followed up by telephone interviews. In hospital, patients with renal failure suffered significantly more often from local complications (12.1 vs 0%, P = 0.004) and acute deterioration of renal function after PTCA (7.6 vs 0%, P = 0.023) than their matched controls. Angiographic success after PTCA was not significantly different (85 vs 83%, n.s.) as was the case with in-hospital mortality (6.1 vs 3.0%, n.s.). During follow up (100% complete), 18 patients (27.3%) with renal failure had died compared with seven controls (10.6%; OR 3.2, P = 0.015). Even if deaths from non-cardiac causes in three patients with renal failure were excluded, death after PTCA occurred significantly more often in the renal failure group (P = 0.015, log rang test). Multivariate analyses with stepwise logistic regression identified impaired left ventricular function (OR 2.24, 95%CI 1.33-3.77), elevated serum creatinine (OR 2.02, 95%CI 1.24-3.31) and smaller height (OR 0.91, 95%CI 0.86-0.98) to be independently associated with death. In conclusion, in this matched-pair study, patients with chronic renal failure suffered from more in-hospital complications and from markedly increased long-term mortality after PTCA.