Institutional Variation in Mortality After Stroke After Cardiac Surgery: An Opportunity for Improvement

Risk factors and operative risk of large vessel occlusion and stroke during cardiac surgery

OBJECTIVE

Perioperative Large Vessel Occlusions (LVOs) occurring during and following surgery are of immense clinical importance. As such, we aim to present risk factors and test if the Society of Thoracic Surgery (STS) mortality and stroke risk scores can be used to assess operative risk.

METHODS

Using data containing 7 index cardiac operations at a single tertiary referral center from 2010 to 2022, logistic and multivariate regression analysis was performed to identify factors that correlate to higher operative LVO and stroke rate. Odds ratios and confidence intervals were also obtained to test if the STS-Predicted Risk of Mortality (PROM) and -Predicted Risk of Stroke (PROS) scores were positively correlated to operative LVO and stroke rate.

RESULTS

Multivariate modeling showed primary risk factors for an operative LVO were diabetes (OR: 1.727 [95 % CI: 1.060-2.815]), intracranial or extracranial carotid stenosis (OR: 3.661 [95 % CI: 2.126-6.305]), and heart failure as defined by NYHA class (Class 4, OR: 3.951 [95 % CI: 2.092-7.461]; compared to Class 1). As the STS-PROM increased, the relative rate of LVO occurrence increased (very high risk, OR: 6.576 [95 % CI: 2.92-14.812], high risk, OR: 2.667 [1.125-6.322], medium risk, OR: 2.858 [1.594-5.125]; all compared to low risk). STS-PROS quartiles showed a similar relation with LVO risk (quartile 4, OR: 7.768 [95 % CI: 2.740-22.027], quartile 3, OR: 5.249 [1.800-15.306], quartile 2, OR:2.980 [0.960-9.248]; all compared to quartile 1).

CONCLUSIONS

Patients with diabetes, carotid disease and heart failure are at high risk for operative LVO. Both STS-PROM and -PROS can be useful metrics for preoperative measuring of LVO risks.

Postoperative stroke assessment inconsistencies in cardiac surgery: Contributors to higher stroke-related mortality?

OBJECTIVES

In-hospital stroke mortality is surprisingly much worse than for strokes occurring outside of the hospital. Cardiac surgery patients are amongst the highest risk groups for in-hospital stroke and experience high stroke-related mortality. Variability in institutional practices appears to play an important role in the diagnosis, management, and outcome of postoperative stroke. We therefore tested the hypothesis that variability in postoperative stroke management of cardiac surgical patients exists across institutions.

MATERIALS AND METHODS

A 13 item survey was employed to determine postoperative stroke practice patterns for cardiac surgical patients across 45 academic institutions.

RESULTS

Less than half (44%) reported any formal clinical effort to preoperatively identify patients at high risk for postoperative stroke. Epiaortic ultrasonography for the detection of aortic atheroma, a proven preventative measure, was routinely practiced in only 16% of institutions. Forty-four percent (44%) reported not knowing whether a validated stroke assessment tool was utilized for the detection of postoperative stroke, and 20% reported that validated tools were not routinely used. All responders, however, confirmed the availability of stroke intervention teams.

CONCLUSIONS

Adoption of a best practices approach to the management of postoperative stroke is highly variable and may improve outcomes in postoperative stroke after cardiac surgery.

Failure to Rescue: A Quality Metric for Cardiac Surgery and Cardiovascular Critical Care

Failure to rescue, defined as mortality after a surgical complication, is a widely accepted quality metric across many specialties and is becoming an important metric in cardiac surgery. The failure to rescue metric provides a target for improvements in patient outcomes after complications occur. To be used appropriately, the failure to rescue metric must be defined using a prespecified set of life-threatening and rescuable complications. Successful patient rescue requires a systematic approach of complication recognition, timely escalation of care, effective medical management, and mitigation of additional complications. This process requires contributions from cardiac surgeons, intensivists, and other specialists including cardiologists, neurologists, and anaesthesiologists. Factors that affect failure to rescue rates in cardiac surgery and cardiovascular critical care include nurse staffing ratios, intensivist coverage, advanced specialist support, hospital and surgical volume, the presence of trainees, and patient comorbidities. Strategies to improve patient rescue include working to understand the mechanisms of failure to rescue, anticipating postoperative complications, prioritizing microsystem factors, enhancing early escalation of care, and educating and empowering junior clinicians. When used appropriately, the failure to rescue quality metric can help institutions focus on improving processes of care that minimize morbidity and mortality from rescuable complications after cardiac surgery.

Perioperative stroke and survival in coronary artery bypass grafting patients: a SWEDEHEART study

OBJECTIVES

Perioperative stroke is a severe complication of cardiac surgery. We assessed the incidence of stroke over time, the association between stroke and mortality and identified preoperative factors independently associated with perioperative stroke, in a large nationwide cardiac surgery population.

METHODS

All patients who underwent coronary artery bypass grafting in Sweden 2006-2017 were included in a registry-based observational cohort study based on prospectively collected data. Multivariable logistic and Cox regression models were used to assess associations between perioperative stroke and mortality and to identify factors associated with stroke. The median follow-up was 6 years (range 0-12).

RESULTS

There were 441 perioperative strokes in 36 898 patients. The mean incidence was 1.2% and decreased marginally over time [adjusted odds ratio (OR) 0.97 per year (95% confidence interval 0.94-1.00), P = 0.035]. Stroke patients had a higher overall mortality risk during follow-up [adjusted hazard ratio 2.30 (2.00-2.64), P < 0.001], with the highest risk during the first 30 postoperative days [adjusted hazard ratio (7.29 (5.58-9.54), P < 0.001]. The strongest independent preoperative factors associated with stroke were prior cardiac surgery [adjusted OR 2.89 (1.40-5.96)], critical preoperative condition [adjusted OR 2.55 (1.73-3.76)], previous stroke [adjusted OR 1.77 (1.35-2.33)], preoperative angina requiring intravenous nitrates [adjusted OR 1.67 (1.28-2.17)], peripheral vascular disease [OR 1.63 (1.25-2.13)] and advanced age [OR 1.05 (1.03-1.06) per year].

CONCLUSIONS

The incidence of perioperative stroke after coronary artery bypass grafting has remained stable. Patients with perioperative stroke had a markedly higher adjusted risk of death early after surgery. The risk declined over time but remained higher during the entire follow-up period.

Center Variability in Medicare Claims-Based Publicly Reported Transcatheter Aortic Valve Replacement Outcome Measures

Background

Public reporting of transcatheter aortic valve replacement (TAVR) claims–based outcome measures is used to identify high‐ and low‐performing centers. Whether claims‐based TAVR outcomes can reliably be used for center‐level comparisons is unknown. In this study, we sought to evaluate center variability in claims‐based TAVR outcomes used in public reporting.

Methods and Results

The study sample included 119 554 Medicare beneficiaries undergoing TAVR between January 2014 and October 2018 based on procedure codes in 100% Medicare inpatient claims. Multivariable hierarchical logistic regression was used to estimate center‐specific adjusted rates and reliability (R) of 30‐day mortality, discharge not to home/self‐care, 30‐day stroke, and 30‐day readmission. Reliability was defined as the ratio of between‐hospital variation to the sum of the between‐ and within‐hospital variation. The median (interquartile range [IQR]) center‐level adjusted outcome rates were 3.1% (2.9%–3.4%) for 30‐day mortality, 41.4% (31.3%–53.4%) for discharge not to home, 2.5% (2.3%–2.7%) for 30‐day stroke, and 14.9% (14.4%–15.5%) for 30‐day readmission. Median reliability was highest for the discharge not to home measure (R=0.95; IQR, 0.94–0.97), followed by the 30‐day stroke (R=0.92; IQR, 0.87–0.94), 30‐day mortality (R=0.86; IQR, 0.81–0.91), and 30‐day readmission measures (R=0.42; IQR, 0.35–0.51). Across outcomes, there was an inverse relationship between center volume and measure reliability.

Conclusions

Claims‐based TAVR outcome measures for mortality, discharge not to home, and stroke were reliable measures for center‐level comparisons, but readmission measures were unreliable. Stakeholders should consider these findings when evaluating claims‐based measures to compare center‐level TAVR performance.

Institutional mortality rate and cause of death at health facilities in Ghana between 2014 and 2018

BACKGROUND

The epidemiological transition, touted as occurring in Ghana, requires research that tracks the changing patterns of diseases in order to capture the trend and improve healthcare delivery. This study examines national trends in mortality rate and cause of death at health facilities in Ghana between 2014 and 2018.

METHODS

Institutional mortality data and cause of death from 2014-2018 were sourced from the Ghana Health Service's District Health Information Management System. The latter collates healthcare service data routinely from government and non-governmental health institutions in Ghana yearly. The institutional mortality rate was estimated using guidelines from the Ghana Health Service. Percent change in mortality was examined for 2014 and 2018. In addition, cause of death data were available for 2017 and 2018. The World Health Organisation's 11th International Classification for Diseases (ICD-11) was used to group the cause of death.

RESULTS

Institutional mortality decreased by 7% nationally over the study period. However, four out of ten regions (Greater Accra, Volta, Upper East, and Upper West) recorded increases in institutional mortality. The Upper East (17%) and Volta regions (13%) recorded the highest increase. Chronic non-communicable diseases (NCDs) were the leading cause of death in 2017 (25%) and 2018 (20%). This was followed by certain infectious and parasitic diseases (15% for both years) and respiratory infections (10% in 2017 and 13% in 2018). Among the NCDs, hypertension was the leading cause of death with 2,243 and 2,472 cases in 2017 and 2018. Other (non-ischemic) heart diseases and diabetes were the second and third leading NCDs. Septicaemia, tuberculosis and pneumonia were the predominant infectious diseases. Regional variations existed in the cause of death. NCDs showed more urban-region bias while infectious diseases presented more rural-region bias.

CONCLUSIONS

This study examined national trends in mortality rate and cause of death at health facilities in Ghana. Ghana recorded a decrease in institutional mortality throughout the study. NCDs and infections were the leading causes of death, giving a double-burden of diseases. There is a need to enhance efforts towards healthcare and health promotion programmes for NCDs and infectious diseases at facility and community levels as outlined in the 2020 National Health Policy of Ghana.

Intimal aortic atherosclerosis in cardiac surgery: surgical strategies to prevent embolic stroke

 

OBJECTIVES

Although the incidence of perioperative stroke after cardiac surgery gradually decreased over the last decades, there is much variation between centres. This review aimed to create a concise overview of the evidence on possible surgical strategies to prevent embolic stroke in patients with intimal aortic atherosclerosis.

METHODS

The PubMed and EMBASE databases were searched for studies on surgical management of aortic atherosclerosis and the association with perioperative stroke in cardiac surgery, including specific searches on the most common types of surgery. Articles were screened with emphasis on studies comparing multiple strategies and studies reporting on the patients’ severity of aortic atherosclerosis. The main findings were summarized in a figure, with a grade of the corresponding level of evidence.

RESULTS

Regarding embolic stroke risk, aortic atherosclerosis of the tunica intima is most relevant. Although several strategies in general cardiac surgery seem to be beneficial in severe disease, none have conclusively been proven most effective. Off-pump surgery in coronary artery bypass grafting should be preferred with severe atherosclerosis, if the required expertise is present. Although transcatheter aortic valve replacement is used as an alternative to surgery in patients with a porcelain aorta, the risk profile concerning intimal atherosclerosis remains poorly defined.

CONCLUSIONS

A tailored approach that uses the discussed alternative strategies in carefully selected patients is best suited to reduce the risk of perioperative stroke without compromising other outcomes. More research is needed, especially on the perioperative stroke risk in patients with moderate aortic atherosclerosis.

Mechanical Thrombectomy Improves Outcome for Large Vessel Occlusion Stroke after Cardiac Surgery

BACKGROUND

Stroke is a feared complication of cardiac surgery. Modern clot-retrieval techniques provide effective treatment for large vessel occlusion (LVO) strokes. The purpose of this study was to 1) report the incidence of LVO stroke after cardiac surgery at a large academic center, and 2) describe outcomes of postoperative LVO strokes.

METHODS

All patients experiencing stroke within 30 days after undergoing cardiac surgery at a single center in 2014-2018 were reviewed. LVOs were identified through review of imaging and medical records, and their characteristics and clinical courses were examined.

RESULTS

Over the study period, 7,112 cardiac surgeries, including endovascular procedures, were performed. Acute ischemic stroke within 30 days after surgery was noted in 163 patients (2.3%). Among those with a stroke, 51/163 (31.3%) had a CTA or MRA, and 15/163 (9.2%) presented with LVO stroke. For all stroke patients, the median time from surgery to stroke was 2 days (interquartile range, IQR, 0-6 days), and for patients with LVO, the median time from surgery to stroke was 4 days (IQR 0-6 days). The overall rate of postoperative LVO was 0.2% (95% CI 0.1-0.4%), though only 6/15 received thrombectomy. LVO patients receiving thrombectomy were significantly more likely to return to independent living compared to those managed medically (n = 4/6, 66.6% for mechanical thrombectomy vs. n = 0/9, 0% for medical management, P = .01). Of the 9 patients who did not get thrombectomy, 6 may currently be candidates for thrombectomy given new expanded treatment windows.

CONCLUSIONS

The rate of LVO after cardiac surgery is low, though substantially elevated above the general population, and the majority do not receive thrombectomy currently. Patients receiving thrombectomy had improved neurologic outcomes compared to patients managed medically. Optimized postoperative care may increase the rate of LVO recognition, and cardiac surgery patients and their caregivers should be aware of this effective therapy.

Low left ventricular ejection fraction, complication rescue, and long-term survival after coronary artery bypass grafting

OBJECTIVES

To evaluate the association between low left ventricular ejection fraction (LVEF), complication rescue, and long-term survival after isolated coronary artery bypass grafting.

METHODS

National cohort study of patients who underwent isolated coronary artery bypass grafting (2000-2016) using Veterans Affairs Surgical Quality Improvement Program data. Left ventricular ejection fraction was categorized as ≥35% (n = 55,877), 25%-34% (n = 3893), or <25% (n = 1707). Patients were also categorized as having had no complications, 1 complication, or more than 1 complication. The association between LVEF, complication rescue, and risk of death was evaluated with multivariable Cox regression.

RESULTS

Among 61,477 patients, 6586 (10.7%) had a perioperative complication and 2056 (3.3%) had multiple complications. Relative to LVEF ≥35%, decreasing ejection fraction was associated with greater odds of complications (25%-34%, odds ratio, 1.30 [1.18-1.42]; <25%, odds ratio, 1.65 [1.43-1.92]). There was a dose-response relationship between decreasing LVEF and overall risk of death (≥35% [ref]; 25%-35%, hazard ratio, 1.46 [1.37-1.55]; <25%, hazard ratio, 1.68 [1.58-1.79]). Among patients who were rescued from complications, there were decreases in 10-year survival, regardless of LVEF. Among those rescued after multiple complications, LVEF was no longer associated with risk of death.

CONCLUSIONS

While decreasing LVEF is associated with post-coronary artery bypass grafting complications, patients rescued from complications have worse long-term survival, regardless of left ventricular function. Prevention and timely treatment of complications should remain a focus of quality improvement initiatives, and future work is needed to mitigate their long-term detrimental impact on survival.

Failure to rescue in the era of the lung allocation score: The impact of center volume

BACKGROUND

Failure to Rescue (FTR) is a valuable surgical quality improvement metric. The aim of this study is to assess the relationship between center volume and FTR following lung transplantation.

METHODS

Using the database of the United Network for Organ Sharing (UNOS) all adult, primary, isolated lung recipients in the United States between May 2005 and March 2016 were identified. FTR was defined as operative mortality after any of five specific complications. FTR was compared across terciles of transplantation centers stratified based on operative volume.

RESULTS

17,185 lung recipients met study criteria. The composite FTR rate (Death following at least one complication) was 20.7%. Following stratification by volume, FTR rates increased from high to middle tercile centers (19.3% vs. 23.0%). Multivariate logistic regression models suggested an independent relationship between higher center volume and lower FTR rates (p < 0.001).

CONCLUSION

Higher volume lung transplantation centers have lower rates of failure to rescue.

Consequence of Ischemic Stroke after Coronary Surgery with Cardiopulmonary Bypass According to Stroke Subtypes

Introduction

The aim of this study was to determine the outcomes of patients developing ischemic stroke after coronary artery bypass grafting (CABG).

Methods

From March 2012 to January 2017, 5380 consecutive patients undergoing elective coronary surgery were analyzed. Ninety-five patients who developed ischemic strokes after on-pump coronary surgery were included in the study, retrospectively. The cohort was divided into four subgroups [total anterior circulation infarction (TACI), partial anterior circulation infarction (PACI), posterior circulation infarction (POCI), and lacunar infarction (LACI)] according to the Oxfordshire Community Stroke Project (OCSP) classification. The primary endpoints were in-hospital mortality, total mortality, and survival analysis over an average of 30 months of follow-up. The secondary endpoints were the extent of disability and dependency according to modified Rankin Scale (mRS).

Results

The incidence of stroke was 1.76% (n=95). The median age was 62.03±10.06 years and 68 (71.6%) patients were male. The groups were as follows: TACI (n=17, 17.9%), PACI (n=47, 49.5%), POCI (n=20, 21.1%), and LACI (n=11, 11.6%). Twenty-eight (29.5%) patients died in hospital and 34 (35.8%) deaths occurred. The overall mortality rate of the TACI group was significantly higher than that of the LACI group (64.7% vs. 27.3%, P=0.041). The mean mRS score of the TACI group was significantly higher than that of the other groups (P=0.003).

Conclusion

Patients in the TACI group had higher in-hospital and cumulative mortality rates and higher mRS scores. We believe that use of the OCSP classification and the mRS may render it possible to predict the outcomes of stroke after coronary surgery.

Spontaneous Thrombosis of the Aortic Arch after Outpatient Urologic Procedure

A healthy, 42-year-old woman presented to a local community hospital with abdominal pain and left arm pain after laser stone ablation and ureteral stenting performed earlier that day. She was diagnosed with a spontaneous aortic thrombus and embolization of the radial, ulnar and splenic arteries and transferred to a tertiary care facility for cardiothoracic surgery evaluation. This case report discusses her emergency department course, disposition, and one-year outcome.

Cerebral perfusion monitoring in adult patients following cardiac surgery: an observational study

BACKGROUND

Following adult cardiac surgery, often difficult to detect fluctuations in regional cerebral perfusion can contribute to strokes. Optimal cerebral perfusion remains elusive and traditional monitoring strategies do not consistently identify acute changes. Non-invasive cerebral oximetry may detect perfusion variations.

OBJECTIVE

To assess the feasibility of postoperative non-invasive cerebral oximetry monitoring.

METHODS

Non-invasive cerebral oximetry was performed on adult aortic valve surgery patients in a cardiac surgical intensive care unit. Monitoring feasibility was assessed using an investigator-developed, data extraction tool.

RESULTS

Non-invasive cerebral oximetry was completed in 94% of patients. Sixty percent had values that fell below pre-set ischemic threshold. Nurses reported monitoring was feasible, and they perceived identifying deleterious cerebral perfusion trends may improve patient care.

CONCLUSIONS

Prevalence of low cerebral oximetry values underscores the importance of increasing sensitivity of monitoring tools. Further evaluation is required to assess this modality and the role of nurses in optimizing neurocognitive outcomes. Impact statement: Cerebral oximetry monitoring may help identify adult patients at risk of neurological complications after cardiac surgery, and as a consequence initiate definitive therapeutic strategies.

Gender and racial differences in surgical outcomes among adult patients with acute heart failure

BACKGROUND

Approximately three million U.S. adult women have heart failure (HF), increasing their risk of adverse perioperative outcomes. While gender and racial differences are reported in surgical outcomes, less is known about 30-day perioperative outcomes in HF patients.

OBJECTIVES

To characterize and compare gender and racial differences in 30-day perioperative outcomes in adults with new or acute/worsening HF.

METHODS

The 2012-2013 American College of Surgeons National Surgical Quality Improvement Program database of surgical patients (n = 9458) with HF was analyzed. Logistic regression was used to adjust for gender and racial differences in baseline covariates.

RESULTS

No gender difference in mortality (odds ratio = 0.922, 95% confidence interval = 0.0792-1.073, p = 0.294) was noted. Whites were more likely than Blacks to die 30 days after surgery (14% vs 9%, p < 0.001); after adjustment, Blacks were more likely to experience complications and be readmitted compared to Whites.

CONCLUSIONS

There was no gender difference in mortality. White patients with HF were more likely to die after surgery than Black patients.

Intraoperative tranexamic acid is associated with postoperative stroke in patients undergoing cardiac surgery

BACKGROUND

Stroke is a devastating and potentially preventable complication of cardiac surgery. Tranexamic acid (TXA) is a commonly antifibrinolytic agent in cardiac surgeries with cardiopulmonary bypass (CPB), however, there is concern that it might increase incidence of stroke after cardiac surgery. In this retrospective study, we investigated whether TXA usage could increase postoperative stroke in cardiac surgery.

METHODS

A retrospective study was conducted from January 1, 2010, to December 31, 2015, in 2,016 patients undergoing cardiac surgery, 664 patients received intravenous TXA infusion and 1,352 patients did not receive any antifibrinolytic agent. Univariate and propensity-weighted multivariate regression analysis were applied for data analysis.

RESULTS

Intraoperative TXA administration was associated with postoperative stroke (1.7% vs. 0.5%; adjusted OR, 4.11; 95% CI, 1.33 to 12.71; p = 0.014) and coma (adjusted OR, 2.77; 95% CI, 1.06 to 7.26; p = 0.038) in cardiac surgery. As subtype analysis was performed, TXA administration was still associated with postoperative stroke (1.7% vs. 0.3%; adjusted OR, 5.78; 95% CI, 1.34 to 27.89; p = 0.018) in patients undergoing valve surgery or multi-valve surgery only, but was not associated with postoperative stroke (1.7% vs. 1.3%; adjusted OR, 5.21; 95% CI, 0.27 to 101.17; p = 0.276) in patients undergoing CABG surgery only. However, TXA administration was not associated with postoperative mortality (adjusted OR, 1.31; 95% CI, 0.56 to 3.71; p = 0.451), seizure (adjusted OR, 1.13; 95% CI, 0.42 to 3.04; p = 0.816), continuous renal replacement therapy (adjusted OR, 1.36; 95% CI, 0.56 to 3.28; p = 0.495) and resternotomy for postoperative bleeding (adjusted OR, 1.55; 95% CI, 0.55 to 4.30; p = 0.405). No difference was found in postoperative ventilation time (adjusted B, -1.45; SE, 2.33; p = 0.535), length of intensive care unit stay (adjusted B, -0.12; SE, 0.25; p = 0.633) and length of hospital stay (adjusted B, 0.48; SE, 0.58; p = 0.408).

CONCLUSIONS

Based on the 5-year experience of TXA administration in cardiac surgery with CPB, we found that postoperative stroke was associated with intraoperative TXA administration in patients undergoing cardiac surgery, especially in those undergoing valve surgeries only. This study may suggest that TXA should be administrated according to clear indications after evaluating the bleeding risk in patients undergoing cardiac surgery, especially in those with high stroke risk.

Immediate ICU Care for Patients Following Aortic Arch Surgery

Patients undergoing aortic arch surgery are at high risk for stroke, delirium, low cardiac output, respiratory failure, renal failure, and coagulopathy. A significantly higher mortality is seen in patients experiencing any of these complications when compared with those without complications. As surgical, perfusion, and anesthetic techniques improve, the incidence of major complications have decreased. A recent paradigm shift in cardiac surgery has focused on rapid postoperative recovery, and a similar change has affected the care of patients after arch surgery. Nevertheless, a small subset of patients experience significant morbidity and mortality after aortic arch surgery, and rapid identification of any organ dysfunction and appropriate supportive care is critical in these patients. In this article, the current state of postoperative care of the patient after open aortic arch surgery will be reviewed.