Improved quality and cost-effectiveness of coronary artery bypass grafting in the United States from 1988 to 2005

Surgical aortic valve replacement in octogenarians: Single-center perioperative outcomes and five-year survival

INTRODUCTION AND OBJECTIVES

Aortic stenosis is the most common valvular heart disease. The number of octogenarians proposed for intervention is growing due to increased lifespan. In this manuscript we aim to evaluate perioperative outcome and long-term survival after surgical aortic valve replacement (SAVR) in octogenarians, comparing patients with low surgical risk (EuroscoreII <4%) with intermediate-high risk (EuroscoreII ≥4%).

METHODS

A retrospective observational single-center cohort study with 195 patients aged ≥80 years old, who underwent SAVR between 2017 and 2021, was conducted. Patients were divided into two groups according to EuroscoreII: (1) Low risk (EuroscoreII <4%) with intermediate-high risk (EuroscoreII ≥4%). Continuous variables are presented in median (IQR), analyzed using Wilcoxon rank sum test; categorical variables in percentages, analyzed using chi-squared test; and survival was analyzed by Kaplan-Meier, open cohort, and the log-rank test was performed.

RESULTS

The overall median age was 82 (IQR 81-83), with 4.6% of the patients ≥85 years old. 23.6% of the patients presented EuroscoreII ≥4%. No complications were observed in 26.2%, with a significantly higher rate in intermediate-high risk patients. Postoperative need for hemodynamic support was the most frequent complication, followed by postoperative acute kidney injury and the use of blood products. Overall median ICU stay was three days (2-4) and hospital length of stay (LOS) six days (5-8). Patients with intermediate-high risk and those with complications had longer ICU LOS. At 12 months, overall survival was 96.4%, at three years 94.1% and 5 years 75.4%. Patients with low surgical risk had higher survival proportions up to 5 years.

CONCLUSION

SAVR in patients ≥80 years is associated with low in-hospital mortality, although a significant proportion of patients develop complications. Long-term follow-up up to five years after surgery is acceptable in octogenarians with low surgical risk.

Population Pharmacokinetics of Prophylactic Cefazolin in Cardiac Surgery with Standard and Minimally Invasive Extracorporeal Circulation

The objectives of this study were to develop a population pharmacokinetic model of prophylactically administered cefazolin in patients undergoing cardiac surgery with and without the use of the cardiopulmonary bypass of both existing types-standard (ECC) and minimallyu invasive extracorporeal circulation (MiECC)-and to propose cefazoline dosing optimization based on this model. A total of 65 adult patients undergoing cardiac surgery were recruited to this clinical trial. A prophylactic cefazolin dose of 2 g was intravenously administered before surgery. Blood samples were collected using a rich sampling design and cefazolin serum concentrations were measured using the HPLC/UV method. The pharmacokinetic population model was calculated using a nonlinear mixed-effects modeling approach, and the Monte Carlo simulation was used to evaluate the PK/PD target attainment. The population cefazolin central volume of distribution (Vd) of 4.91 L increased by 0.51 L with each 1 m2 of BSA, peripheral Vd of 22.07 L was reduced by 0.77 L or 0.79 L when using ECC or MiECC support, respectively, while clearance started at 0.045 L/h and increased by 0.49 L/h with each 1 mL/min/1.73 m2 of eGFR. ECC/MiECC was shown to be covariate of cefazolin Vd, but without relevance to clinical practice, while eGFR was most influential for the PK/PD target attainment. The standard dose of 2 g was sufficient for PK/PD target attainment throughout surgery in patients with normal renal status or with renal impairment. In patients with augmented renal clearance, an additive cefazolin dose should be administered 215, 245, 288 and 318 min after the first dose at MIC of 4, 3, 2 and 1.5 mg/L, respectively.

Preparing for Bundled Payments: Impact of Complications Post-Coronary Artery Bypass Grafting on Costs

BACKGROUND

Bundled payments for coronary artery bypass grafting (CABG) provide a single reimbursement for care provided from admission through 90 days post-discharge. We aim to explore the impact of complications on total institutional costs, as well as the drivers of high costs for index hospitalization.

METHODS

We linked clinical and internal cost data for patients undergoing CABG from 2014 to 2017 at a single institution. We compared unadjusted average variable direct costs, reporting excess cost from an uncomplicated baseline. We stratified by The Society of Thoracic Surgeons preoperative risk and quality outcome measures as well as value-based outcomes (readmission, post-acute care utilization). We performed multivariable linear regression to evaluate drivers of high costs, adjusting for preoperative and intraoperative characteristics and postoperative complications.

RESULTS

We reviewed 1789 patients undergoing CABG with an average of 2.7 vessels (SD 0.89). A significant proportion of patients were diabetic (51.2%) and obese (mean body mass index 30.6, SD 6.1). Factors associated with increased adjusted costs were preoperative renal failure (P = .001), diabetes (P = .001) and body mass index (P = .05), and postoperative stroke (P < .001), prolonged ventilation (P < .001), rebleeding requiring reoperation (P < .001) and renal failure (P < .001) with varying magnitude. Preoperative ejection fraction and insurance status were not associated with increased adjusted costs.

CONCLUSIONS

Preoperative characteristics had less of an impact on costs post-CABG than postoperative complications. Postoperative complications vary in their impact on internal costs, with reoperation, stroke, and renal failure having the greatest impact. In preparation for bundled payments, hospitals should focus on understanding and preventing drivers of high cost.

Predictive factors associated with mortality and discharge in intensive care units: a retrospective cohort study

Background and aim

Accurate prediction of prognosis of patients admitted to intensive care units (ICUs) is very important for the clinical management of the patients. The present study aims to identify independent factors affecting death and discharge in ICUs using competing risk modeling.

Methods

This retrospective cohort study was conducted on enrolling 880 patients admitted to emergency ICU in Namazi hospital, Shiraz University of Medical Sciences, Shiraz, Iran during 2013-2015. The data was collected from patients' medical records using a researcher-made checklist by a trained nurse. Competing risk regression models were fitted for the factors affecting the occurrence of death and discharge in ICU. Data analysis was conducted using STATA 13 and R 3.3.3 software.

Results

Among these patients, 682 (77.5%) were discharged and 157 (17.8%) died in the ICU. The patients' mean ± SD age was 48.90±19.52 yr. Among the study patients, 45.57% were female and 54.43% were male. In the competing risk model, age (Sub-distribution Hazard Ratio (SHR)) =1.02, 95% CI: 1.007-1.032), maximum heart rate (SHR=1.009, 95% CI: 1.001-1.019), minimum sodium level (SHR=1.035, 95% CI: 1.007-1.064), PH (SHR=7.982, 95% CI: 1.259-50.61), and bilirubin (SHR=1.046, 95% CI: 1.015-1.078) increased the risk of death, while maximum sodium level (SHR=0.946, 95% CI: 0.908-0.986) and maximum HCT (SHR=0.938, 95% CI: 0.882-0.998) reduced the risk of death.

Conclusion

In conclusion, the results of this study revealed several variables that were effective in ICU length of stay (LOS). The variables that independently influenced time-to-discharge were age, maximum systolic blood pressure, minimum HCT, maximum WBC, and urine output, maximum HCT and Glasgow coma score. The results also showed that age, maximum heart rate, maximum sodium level, PH, urine output, and bilirubin, minimum sodium level and maximum HCT were the predictors of death. Furthermore, our findings indicated that the competing risk model was more appropriate than the Cox model in evaluating the predictive factors associated with the occurrence of death and discharge in patients hospitalized in ICUs. Hence, this model could play an important role in managers' and clinicians' decision-making and improvement of the standard of care in ICUs.

Development of the Cardiac Surgery Patient Expectations Questionnaire (C-SPEQ)

PURPOSE

Some variability in recovery and outcomes after cardiac surgery may be influenced by psychosocial aspects not routinely captured. Preliminary evidence suggests patient expectations impact health status, but there is no specific measure of expectations for cardiac surgery. The purpose of this study was to adapt an expectations scale to cardiac surgery and assess the psychometric properties of the scale.

METHODS

Before surgery, 93 patients awaiting non-emergent cardiac surgery completed questionnaires, including the adapted Cardiac Surgery Patient Expectations Questionnaire (C-SPEQ). At 1 year after surgery, 68 patients completed questionnaires.

RESULTS

Mean C-SPEQ score was 39.4 ± 9.02, and scores were normally distributed (Cronbach's alpha = 0.86). Higher score indicated negative expectations. Higher presurgery C-SPEQ score was correlated with greater depression (r = 0.32, p = 0.01) and perceived stress (r = 0.36, p = 0.003), but not state anxiety (r = 0.18, p = 0.14), at one-year post-surgery. Higher C-SPEQ was associated with longer recovery time (B = 0.14, p = 0.006) and lower physical HRQL after surgery (B = -0.31, p = 0.005). Higher C-SPEQ was not related to greater odds for perioperative complications (OR 1.01, p = 0.68) or readmissions <30 days (OR 1.05, p = 0.31). C-SPEQ score was not related to survival.

CONCLUSIONS

Adaptation of an expectations questionnaire to cardiac surgery patients was successful with acceptable reliability and validity. Negative expectations had a detrimental impact on recovery and HRQL following cardiac surgery but were not related to clinical outcomes. Although focus is mainly on improving clinical outcomes, there are opportunities to improve non-clinical aspects of the patient experience. Presurgical education might better prepare patients, reduce negative expectations, and improve psychosocial outcomes after cardiac surgery.

Use of minimal invasive extracorporeal circulation in cardiac surgery: principles, definitions and potential benefits. A position paper from the Minimal invasive Extra-Corporeal Technologies international Society (MiECTiS)

Minimal invasive extracorporeal circulation (MiECC) systems have initiated important efforts within science and technology to further improve the biocompatibility of cardiopulmonary bypass components to minimize the adverse effects and improve end-organ protection. The Minimal invasive Extra-Corporeal Technologies international Society was founded to create an international forum for the exchange of ideas on clinical application and research of minimal invasive extracorporeal circulation technology. The present work is a consensus document developed to standardize the terminology and the definition of minimal invasive extracorporeal circulation technology as well as to provide recommendations for the clinical practice. The goal of this manuscript is to promote the use of MiECC systems into clinical practice as a multidisciplinary strategy involving cardiac surgeons, anaesthesiologists and perfusionists.

Cardiac surgery in 260 octogenarians: a case series

Background

The elderly undergo cardiac surgery more and more frequently, often present multiple comorbidities, assume chronic therapies, and present a unique physiology. Aim of our study was to analyze the experience of a referral cardiac surgery center with all types of cardiac surgery interventions performed in patients ≥80 years old over a six years’ period.

Methods

A retrospective observational study performed in a university hospital. 260 patients were included in the study (3.5% of the patients undergoing cardiac surgery in the study period).

Results

Mean age was 82 ± 1.8 years. Eighty-five percent of patients underwent elective surgery, 15% unplanned surgery and 4.2% redo surgery. Intervention for aortic valve pathology and coronary artery bypass grafting were performed in 51% and 46% of the patients, respectively. Interventions involving the mitral valve were the 26% of the total, those on the tricuspid valve were 13% and those on the ascending aortic arch the 9.6%. Postoperative low output syndrome was identified in 44 patients (17%). Mortality was 3.9% and most of the patients (91%) were discharged from hospital in good clinical conditions. Hospital mortality was lower in planned vs unplanned surgery: 3.8% vs 14% respectively. Chronic obstructive pulmonary disease (OR 9.106, CI 2.275 – 36.450) was the unique independent predictor of mortality.

Conclusions

Clinicians should be aware that cardiac surgery can be safely performed at all ages, that risk stratification is mandatory and that hemodynamic treatment to avoid complications is expected.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2253-15-15) contains supplementary material, which is available to authorized users.

Customized Prediction of Short Length of Stay Following Elective Cardiac Surgery in Elderly Patients Using a Genetic Algorithm

Objective

To develop a customized short LOS (<6 days) prediction model for geriatric patients receiving cardiac surgery, using local data and a computational feature selection algorithm.

Design

Utilization of a machine learning algorithm in a prospectively collected STS database consisting of patients who received cardiac surgery between January 2002 and June 2011.

Setting

Urban tertiary-care center.

Participants

Geriatric patients aged 70 years or older at the time of cardiac surgery.

Interventions

None.

Measurements and Main Results

Predefined morbidity and mortality events were collected from the STS database. 23 clinically relevant predictors were investigated for short LOS prediction with a genetic algorithm (GenAlg) in 1426 patients. Due to the absence of an STS model for their particular surgery type, STS risk scores were unavailable for 771 patients. STS prediction achieved an AUC of 0.629 while the GenAlg achieved AUCs of 0.573 (in those with STS scores) and 0.691 (in those without STS scores). Among the patients with STS scores, the GenAlg features significantly associated with shorter LOS were absence of congestive heart failure (CHF) (OR = 0.59, p = 0.04), aortic valve procedure (OR = 1.54, p = 0.04), and shorter cross clamp time (OR = 0.99, p = 0.004). In those without STS prediction, short LOS was significantly correlated with younger age (OR = 0.93, p < 0.001), absence of CHF (OR = 0.53, p = 0.007), no preoperative use of beta blockers (OR = 0.66, p = 0.03), and shorter cross clamp time (OR = 0.99, p < 0.001).

Conclusion

While the GenAlg-based models did not outperform STS prediction for patients with STS risk scores, our local-data-driven approach reliably predicted short LOS for cardiac surgery types that do not allow STS risk calculation. We advocate that each institution with sufficient observational data should build their own cardiac surgery risk models.

Bilateral internal mammary artery grafting enhances survival in diabetic patients: a 30-year follow-up of propensity score-matched cohorts

BACKGROUND

The prevalence of diabetes mellitus is increasing at an unprecedented rate, affecting nearly 8% of the population. Previous studies have demonstrated a potential benefit for surgical over interventional revascularization in this group of patients. Similarly, studies have shown the superiority of bilateral internal mammary artery (BIMA) grafting over single internal mammary artery (SIMA) grafting in select populations. However, concerns about sternal wound infection have discouraged the use of BIMA grafting in diabetics. Therefore, we studied the long-term results of BIMA versus SIMA grafting in a large population of diabetic patients in whom BIMA grafting was broadly applied.

METHODS AND RESULTS

Between February 1972 and May 1994, 1107 consecutive diabetic patients underwent coronary artery bypass grafting with either SIMA (n=646) or BIMA (n=461) grafting. Optimal matching with the propensity score was used to create matched SIMA (n=414) and BIMA (n=414) cohorts. Cross-sectional follow-up (6 weeks to 30.1 years; mean, 8.9 years) determined long-term survival. There was no difference in operative mortality, sternal wound infection, or total complications between matched SIMA and BIMA groups (operative mortality, 10 of 414 [2.4%] versus 13 of 414 [3.1%]; P=0.279; sternal wound infection, 7 of 414 [1.7%] versus 13 of 414 [3.1%]; P=0.179); total complications, 71 of 414 [17.1%] versus 71 of 414 [17.1%]; P=1.000). Late survival was significantly enhanced with the use of BIMA grafting (median survival: SIMA, 9.8 years versus BIMA, 13.1 years; P=0.001). Use of BIMA was found to be associated with late survival on Cox regression (P=0.003).

CONCLUSION

Compared with SIMA grafting, BIMA grafting in propensity score-matched patients provides diabetics with enhanced survival without any increase in perioperative morbidity or mortality.

Challenges in intraoperative monitoring

Predicting major adverse events following surgery remains a significant problem. Currently, the perioperative period is too often considered a black box, with risk assessment and prediction largely based on static pre-surgical parameters. Here, we review the problem of intraoperative hypotension and outline some of the opportunities for improved monitoring during surgery.

Impact of completeness of revascularization on long-term cardiovascular outcomes in patients with type 2 diabetes mellitus: results from the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D)

BACKGROUND

Patients with diabetes have more extensive coronary disease than those without diabetes, resulting in more challenging percutaneous coronary intervention or surgical (coronary artery bypass graft) revascularization and more residual jeopardized myocardium. The Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial provided an opportunity to examine the long-term clinical impact of completeness of revascularization in patients with diabetes.

METHODS AND RESULTS

This is a post hoc, nonrandomized analysis of the completeness of revascularization in 751 patients who were randomly assigned to early revascularization, of whom 264 underwent coronary artery bypass graft surgery and 487 underwent percutaneous coronary intervention. The completeness of revascularization was determined by the residual postprocedure myocardial jeopardy index (RMJI). RMJI is a ratio of the number of myocardial territories supplied by a significantly diseased epicardial coronary artery or branch that was not successfully revascularized, divided by the total number of myocardial territories. Mean follow-up for mortality was 5.3 years. Complete revascularization (RMJI=0) was achieved in 37.9% of patients, mildly incomplete revascularization (RMJI >0≤33) in 46.6%, and moderately to severely incomplete revascularization (RMJI >33) in 15.4%. Adjusted event-free survival was higher in patients with more complete revascularization (hazard ratio, 1.14; P=0.0018).

CONCLUSIONS

Patients with type 2 diabetes mellitus and less complete revascularization had more long-term cardiovascular events.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00006305.

A multinational study of the influence of health-related quality of life on in-hospital outcome after coronary artery bypass graft surgery

BACKGROUND

The effect of health-related quality of life on in-hospital outcomes after coronary artery bypass grafting surgery has not been investigated in international multicenter studies. We hypothesized that poor preoperative health status is associated with mortality and length of hospital stay.

METHODS

In the Multicenter Study of Perioperative Ischemia Epidemiology II, preoperative Short-Form 12, Mental Component Summary (MCS), and Physical Component Summary (PCS) scores were obtained prospectively from 4,811 patients (3,834 men, 977 women) undergoing coronary artery bypass grafting surgery at 72 centers in 17 countries. Primary outcome measures were in-hospital mortality and prolonged (>14 days) length of hospital stay.

RESULTS

One hundred fifty-one patients (3.1%) died. After adjustment for regional differences, a 10-point reduction in MCS score was associated with higher mortality risk (odds ratio [OR] 1.17, 95% CI 1.004-1.37, P = .04) and prolonged hospital stay (OR 1.11, 95% CI 1.01-1.21, P = .03). The preoperative PCS score was not associated with mortality risk but significantly predicted prolonged length of hospital stay (OR 1.20, 95% CI 1.09-1.33, P < .001). There was no significant interaction between gender and either the MCS or the PCS score.

DISCUSSION

The preoperative PCS predicted prolonged postoperative hospital stay, whereas the preoperative MCS score was an independent predictor of both prolonged length of hospital stay and mortality. Preoperative assessment of health-related quality of life factors with the Short-Form 12 might be a useful tool for risk stratification and planning for hospital discharge and rehabilitation.

Heparinized cardiopulmonary bypass circuits and low systemic anticoagulation: an analysis of nearly 6000 patients undergoing coronary artery bypass grafting

OBJECTIVE

Heparin coating of cardiopulmonary bypass circuits reduces the inflammatory response and increases the thromboresistance during extracorporeal circulation. These properties enables a lower systemic heparin dose, which has been shown to reduce the need for blood transfusions. Experience with this technique accumulated over 11 years has been analyzed.

METHODS

All patients underwent on-pump coronary artery bypass grafting with heparin-coated circuits. Apart from some patients receiving a high intraoperative dose of aprotinin, the systemic heparin dose was reduced, with a lower level of an activated clotting time of 250 seconds during extracorporeal circulation. The overall strategy aimed at a fast-track regimen, with early extubation, minimal use of blood transfusions, and rapid postoperative recovery.

RESULTS

Altogether, 5954 patients were included; 1131 (19.0%) were female (median age, 70 years), and 4823 were male (median age, 65 years). The median additive EuroSCORE was 3 (range, 0-14; mean 3.5 ± 2.5). No significant signs of clotting were seen in any part of the extracorporeal circuit. Bank blood products were given to 427 (7.2%) patients. Median extubation time was 1.7 hours. The stroke rate was 1.0%, transient neurologic deficits occurred in 0.7%, and perioperative myocardial infarction occurred in 1.2%. On the fifth day, 88.1% of the patients were physically rehabilitated and ready for discharge. Thirty-day mortality was 0.9% (54 patients).

CONCLUSIONS

The experience with this patient cohort including mostly low- to medium-risk patients with a relatively short cardiopulmonary bypass time indicates that coronary artery bypass grafting performed with heparin-coated circuits and reduced level of systemic heparinization is safe and results in a very satisfactory clinical course. No signs of clotting or other technical incidents were recorded.