Renal insufficiency and altered postoperative risk in carotid endarterectomy

Outcomes of carotid revascularization stratified by procedure in patients with an estimated glomerular filtration rate of <30 and dialysis patients

OBJECTIVE

Renal failure is a predictor of adverse outcomes in carotid revascularization. There has been debate regarding the benefit of revascularization in patients with severe chronic kidney disease or on dialysis.

METHODS

Patients in the Vascular Quality Initiative undergoing transcarotid artery revascularization (TCAR), transfemoral carotid artery stenting (tfCAS), or CEA between 2016 and 2023 with an estimated glomerular filtration rate (eGFR) of <30 mL/min/1.73 m2 or on dialysis were included. Patients were divided into cohorts based on procedure. Additional analyses were performed for patients on dialysis only and by symptomatology. Primary outcomes were perioperative stroke/death/myocardial infarction (MI) (SDM). Secondary outcomes included perioperative death, stroke, MI, cranial nerve injury, and stroke/death. Inverse probability of treatment weighting was performed based on treatment assignment to TCAR, tfCAS, and CEA patients and adjusted for demographics, comorbidities, and preoperative symptoms. The χ2 test and multivariable logistic regression analysis were used to evaluate the association of procedure with perioperative outcomes in the weighted cohort. Five-year survival was evaluated using Kaplan-Meier and weighted Cox regression.

RESULTS

In the weighted cohort, 13,851 patients with an eGFR of <30 (2506 on dialysis) underwent TCAR (3639; 704 on dialysis), tfCAS (1975; 393 on dialysis), or CEA (8237; 1409 on dialysis) during the study period. Compared with TCAR, CEA had higher odds of SDM (2.8% vs 3.6%; adjusted odds ratio [aOR], 1.27; 95% confidence interval [CI], 1.00-1.61; P = .049), and MI (0.7% vs 1.5%; aOR, 2.00; 95% CI, 1.31-3.05; P = .001). Compared with TCAR, rates of SDM (2.8% vs 5.8%), stroke (1.2% vs 2.6%), and death (0.9% vs 2.4%) were all higher for tfCAS. In asymptomatic patients CEA patients had higher odds of MI (0.7% vs 1.3%; aOR, 1.85; 95% CI, 1.15-2.97; P = .011) and cranial nerve injury (0.3% vs 1.9%; aOR, 7.23; 95% CI, 3.28-15.9; P < .001). Like in the primary analysis, asymptomatic tfCAS patients demonstrated higher odds of death and stroke/death. Symptomatic CEA patients demonstrated no difference in stroke, death, or stroke/death. Although tfCAS patients demonstrated higher odds of death, stroke, MI, stroke/death, and SDM. In both groups, the 5-year survival was similar for TCAR and CEA (eGFR <30, 75.1% vs 74.2%; aHR, 1.06; P = .3) and lower for tfCAS (eGFR <30, 75.1% vs 70.4%; aHR, 1.44; P < .001).

CONCLUSIONS

CEA and TCAR had similar odds of stroke and death and are both a reasonable choice in this population; however, TCAR may be better in patients with an increased risk of MI. Additionally, tfCAS patients were more likely to have worse outcomes after weighting for symptom status. Finally, although patients with a reduced eGFR have worse outcomes than their healthy peers, this analysis shows that the majority of patients survive long enough to benefit from the potential stroke risk reduction provided by all revascularization procedures.

The Minnesota attributable risk of kidney donation (MARKD) study: a retrospective cohort study of long-term (> 50 year) outcomes after kidney donation compared to well-matched healthy controls

BACKGROUND

There is uncertainty about the long-term risks of living kidney donation. Well-designed studies with controls well-matched on risk factors for kidney disease are needed to understand the attributable risks of kidney donation.

METHODS

The goal of the Minnesota Attributable Risk of Kidney Donation (MARKD) study is to compare the long-term (> 50 years) outcomes of living donors (LDs) to contemporary and geographically similar controls that are well-matched on health status. University of Minnesota (n = 4022; 1st transplant: 1963) and Mayo Clinic LDs (n = 3035; 1st transplant: 1963) will be matched to Rochester Epidemiology Project (REP) controls (approximately 4 controls to 1 donor) on the basis of age, sex, and race/ethnicity. The REP controls are a well-defined population, with detailed medical record data linked between all providers in Olmsted and surrounding counties, that come from the same geographic region and era (early 1960s to present) as the donors. Controls will be carefully selected to have health status acceptable for donation on the index date (date their matched donor donated). Further refinement of the control group will include confirmed kidney health (e.g., normal serum creatinine and/or no proteinuria) and matching (on index date) of body mass index, smoking history, family history of chronic kidney disease, and blood pressure. Outcomes will be ascertained from national registries (National Death Index and United States Renal Data System) and a new survey administered to both donors and controls; the data will be supplemented by prior surveys and medical record review of donors and REP controls. The outcomes to be compared are all-cause mortality, end-stage kidney disease, cardiovascular disease and mortality, estimated glomerular filtration rate (eGFR) trajectory and chronic kidney disease, pregnancy risks, and development of diseases that frequently lead to chronic kidney disease (e.g. hypertension, diabetes, and obesity). We will additionally evaluate whether the risk of donation differs based on baseline characteristics.

DISCUSSION

Our study will provide a comprehensive assessment of long-term living donor risk to inform candidate living donors, and to inform the follow-up and care of current living donors.

Carotid Artery Stenting for Asymptomatic Carotid Stenosis: What We Need to Know for Treatment Decision

A clinical decision on the treatment of asymptomatic carotid stenosis is challenging, unlike symptomatic carotid stenosis. Carotid artery stenting (CAS) has been recommended as an alternative to carotid endarterectomy (CEA) based on the finding that the efficacy and safety of CAS were comparable to CEA in randomized trials. However, in some countries, CAS is often performed more frequently than CEA for asymptomatic carotid stenosis. Moreover, it has been recently reported that CAS is not superior to the best medical treatment in asymptomatic carotid stenosis. Due to these recent changes, the role of CAS in asymptomatic carotid stenosis should be revisited. When determining the treatment for asymptomatic carotid stenosis, one should consider several clinical factors including stenosis degree, patient life expectancy, stroke risk by medical treatment, availability of a vascular surgeon, high risk for CEA or CAS, and insurance coverage. This review aimed to present and pragmatically organize the information that is necessary for a clinical decision on CAS in asymptomatic carotid stenosis. In conclusion, although the traditional benefit of CAS is being revisited recently, it seems too early to conclude that CAS is no longer beneficial under intense and systemic medical treatment. Instead, a treatment strategy with CAS should evolve to select eligible or medically high-risk patients more precisely.

Long-term Clinical Outcomes of Elective Carotid Artery Stenting in Patients Undergoing Maintenance Hemodialysis

Objective Carotid artery stenting (CAS) in patients undergoing maintenance hemodialysis is characterized by high complication rates. These patients are excluded from clinical trials of CAS. The purpose of our retrospective study was to investigate the long-term clinical outcomes of CAS in patients undergoing maintenance hemodialysis. Methods CAS was performed under local anesthesia. The technical success rate, periprocedural complications, 30-day major vascular event rate (stroke, myocardial infarction, and/or death), 3-month morbidity and mortality rates, and 5-year survival probability were investigated. Patients Nineteen patients undergoing maintenance hemodialysis were identified. Results The mean age of the patients was 69 years. Periprocedural complications occurred in two patients (confusion following CAS in one and transient hemiparesis in the other). Complete neurological recovery was achieved in both patients. No major cardiovascular events occurred within 30 days after CAS. Asymptomatic intracranial hemorrhage only occurred in one patient, and seven patients died during the follow-up period at a mean of 3.5 years after the procedure (range, 6 months to 8 years). No permanent neurologic deficit remained in the patient with intracranial hemorrhage. The causes of death were cardiovascular disease (n = 4), cancer (n = 2), and pneumonia (n = 1). No patients died of stroke. The 5-year survival probability in patients undergoing maintenance hemodialysis was 57%. Conclusion CAS in maintenance hemodialysis patients may be feasible and effective for the prevention of stroke with proper case selection, appropriate technique and strict perioperative management. The most common causes of death during the follow-up of maintenance hemodialysis patients were diseases other than stroke.

Perioperative and long-term impact of chronic kidney disease on carotid artery interventions

OBJECTIVE

Chronic kidney disease (CKD) increases morbidity and mortality after vascular procedures and adversely affects late survival of patients. The presence of CKD also confers increased risk of stroke in patients with asymptomatic carotid stenosis. Patients undergoing carotid intervention in the Vascular Study Group of New England database were stratified by CKD status referable to periprocedural and late outcomes.

METHODS

All carotid artery stenting and carotid endarterectomies (CEAs) performed from 2003 to 2013 were stratified by CKD severity as mild (estimated glomerular filtration rate [eGFR] >60 mL/min/1.73 m²), moderate (eGFR 30-59), and severe (eGFR <30). The impact of CKD on outcomes of carotid procedures was evaluated using univariate and multivariate methods.

RESULTS

Of 12,568 patients identified, 11,746 (93%) underwent CEA and 822 (7%) underwent carotid artery stenting. Procedures were performed for symptomatic disease in 40%. CKD severity was mild in 58%, moderate in 35%, and severe in 7%. The 30-day stroke rate was very low across all CKD groups (1.76% mild vs 1.84% moderate and 1.34% severe; P = .009). The 30-day mortality increased with worsening renal function (0.4% mild vs 0.9% moderate and 0.9% severe; P = .01). Independent predictors of 30-day stroke or death included American Society of Anesthesiologists (ASA) class 4 or 5 (odds ratio, 2.3; 95% confidence interval [CI], 1.5-3.4; P = .0001). Multivariable Cox hazards regression showed that severe CKD (hazard ratio [HR], 1.8; 95% CI, 1.3-2.6), ASA class 4 or 5 (HR, 1.7; 95% CI, 1.3-2.2), preoperative cortical symptoms (HR, 1.5; 95% CI, 1.2-1.8), history of diabetes (HR, 1.4; 95% CI, 1.1-1.7), and age (HR, 1.03/y; 95% CI, 1.02-1.04) independently (all P < .01) predicted neurologic events or death at median follow-up of 12.7 months (interquartile range, 10.3-15.2 months). CKD did not increase the risk of neurologic events at 1-year follow-up. Predictors (P < .05) of late death included moderate CKD (HR, 1.3; 95% CI, 1.01-1.7), severe CKD (HR, 2.2; 95% CI, 1.6-2.9), ASA class 4 or 5 (HR, 1.6; 95% CI, 1.2-2.0), history of diabetes (HR, 1.4; 95% CI, 1.2-1.7), chronic obstructive pulmonary disease (HR, 1.4; 95% CI, 1.1-1.8), and cortical symptoms (HR, 1.3; 95% CI, 1.05-1.6). The 1-, 5-, and 10-year survival rates decreased with worsening renal function (log-rank test, P < .001), but patients with severe CKD maintained a 71% survival at 5 years.

CONCLUSIONS

CKD severity increases risk of perioperative mortality as well as late mortality. Patients with CKD benefit from stroke-free survival especially after CEA. Unlike patients with peripheral arterial occlusive disease, for whom severe CKD reduces median survival to ∼2.5 years, patients with CKD and carotid disease exhibit much longer survival. This suggests that carotid interventions have utility in carefully selected patients with moderate and severe CKD, particularly in symptomatic disease.

A contemporary evaluation of carotid endarterectomy outcomes in patients with chronic kidney disease in the United States

Objectives Chronic kidney disease (CKD) has been identified as a significant risk factor for poor post-surgical outcomes. This study was designed to provide a contemporary analysis of carotid endarterectomy (CEA) outcomes in patients with CKD, end-stage renal disease (ESRD), and normal renal function (NF). Methods The Nationwide Inpatient Sample data 2006-2012 was queried to select patients aging 40 years old and above who underwent CEA during two days after admission and had a diagnosis of ESRD on long-term hemodialysis, patients with non-dialysis-dependent CKD, or NF. Patients with acute renal failure were excluded. We subsequently compared procedure outcomes and hospital resource utilization in these patients. Results Totally 573,723 CEA procedures were estimated: 4801 (ESRD)' 32,988 (CKD)' and 535,934 (NF). Mean age was 71.0 years, 57.7% were males, and 73.7% were white. Overall hospital mortality was 0.20%: 0.69% (ESRD), 0.35% (CKD), and 0.19% (NF), p < 0.0005 between groups. The overall stroke rate was 1.6%: 1.8% (ESRD), 2.0% (CKD), and 1.6% (NF). Comparing NF to CKD there was a significant difference: p < 0.0001. For CKD patients, compared to NF patients, there was an increased risk in cardiac complications (odds ratio = 1.2; 95% CI 1.15-1.32), respiratory complications (odds ratio = 1.2; 95% CI 1.15-1.32), and stroke (odds ratio = 1.1; 95% CI 1.04-1.23). For ESRD patients compared to NF patients there was an increased risk in respiratory complications (odds ratio = 1.3; 95% CI 1.08-1.47) and sepsis (odds ratio = 4.4; 95% CI 3.23-5.94). Mean length of stay and cost were: 2.8 d and $13,903 (ESRD), 2.2 d and $12,057 (CKD), and 1.8 d and $10,130 (NF), all p < 0.0001. Conclusions Patients with ESRD undergoing CEA had an increased risk of respiratory and septic complications, but not a higher risk of stroke compared to patients with normal renal function. The greatest risks of postoperative stroke, respiratory, and cardiac complications were found in patients with CKD. A diagnosis of ESRD and CKD were both found to significantly increase hospital mortality, length of stay and cost. Where clinicians typically consider ESRD patients the highest risk for CEA, further consideration should be given to patients with CKD not yet on dialysis as they had the higher risk of cardiac complications and stroke compared to the others evaluated.

Impact of chronic renal insufficiency on the early and late clinical outcomes of carotid artery stenting using serum creatinine vs glomerular filtration rate

BACKGROUND

This study analyzed the impact of chronic renal insufficiency (CRI) on early and late clinical outcomes of carotid artery stenting (CAS) using serum creatinine and glomerular filtration rate (GFR).

STUDY DESIGN

There were 313 CAS patients classified into 3 groups: normal (serum creatinine <1.5 mg/dL or GFR ≥ 60 mL/min/1.73 m(2)); moderate CRI, and severe CRI (serum creatinine ≥ 3 or GFR < 30 mL/min/1.73 m(2)). Major adverse events ([MAE] stroke, death, and myocardial infarction) were compared for all groups.

RESULTS

Using serum creatinine, perioperative stroke rates for normal, moderate, and severe CRI were: 5%, 0%, and 25%, respectively, (p = 0.05) vs 4.6%, 3.7%, and 11.1%, respectively, (p = 0.44) using GFR. The perioperative MAE rates for symptomatic patients were 9.3% and 0% (p = 0.355) and 2% and 5.9% (p = 0.223) for asymptomatic patients for normal and moderate/severe CRI, respectively, using serum creatinine vs 8.1% and 7.8%, respectively, for symptomatic patients and 2.5% and 3%, respectively, for asymptomatic patients using GFR. At a mean follow-up of 21 months, late MAE rates in normal vs moderate/severe CRI patients were 8.2% and 14%, respectively, (p = 0.247) using serum creatinine vs 6.6% and 13.3%, respectively, (p = 0.05) using GFR. Late MAE rates for symptomatic patients in normal vs moderate/severe CRI were: 8.7% vs 27%, respectively, (p = 0.061) using serum creatinine and 5.7% vs 18.8%, respectively, (p = 0.026) using GFR. Late death rate was 0.55% in normal vs 7.6% (p = 0.002) for moderate/severe CRI. Freedom from MAE at 3 years in symptomatic patients was 81% in normal and 46% in moderate/severe CRI (p = 0.0198). A multivariate Cox regression analysis showed that a GFR of < 60 mL/min/1.73 m(2) had an odds ratio of 1.6 (p = 0.222) of having a MAE after CAS.

CONCLUSIONS

The GFR was more sensitive in detecting late MAE after CAS. Carotid artery stenting in moderate CRI patients can be done with a satisfactory perioperative outcome; however, late death was significant.

In-hospital versus postdischarge adverse events following carotid endarterectomy

OBJECTIVE

Most studies based on state and nationwide registries evaluating perioperative outcome after carotid endarterectomy (CEA) rely on hospital discharge data only. Therefore, the true 30-day complication risk after carotid revascularization may be underestimated.

METHODS

We used the National Surgical Quality Improvement Program database 2005-2010 to assess the in-hospital and postdischarge rate of any stroke, death, cardiac event (new Q-wave myocardial infarction or cardiac arrest), and combined stroke/death and combined adverse outcome (S/D/CE) at 30 days following CEA. Multivariable analyses were used to identify predictors for in-hospital and postdischarge events separately, and in particular, those that predict postdischarge events distinctly.

RESULTS

A total of 35,916 patients who underwent CEA during 2005-2010 were identified in the National Surgical Quality Improvement Program database; 59% were male, median age was 72 years, and 44% had a previous neurologic event. Thirty-day stroke rate was 1.6% (n = 591), death rate was 0.8% (n = 272), cardiac event rate was 1.0% (n = 350), stroke or death rate was 2.2% (n = 794), and combined S/D/CE rate was 2.9% (n = 1043); 33% of strokes, 53% of deaths, 32% of cardiac events, 40% of combined stroke/death, and 38% of combined S/D/CE took place after hospital discharge. Patients with a prior stroke or transient ischemic attack had similar proportions of postdischarge events compared with patients without prior symptoms. Independent predictors for postdischarge events, but not for in-hospital events were female sex (stroke [odds ratio (OR), 1.6; 95% confidence interval (CI), 1.2-2.1] and stroke/death [OR, 1.4; 95% CI, 1.1-1.7]), renal failure (stroke [OR, 3.0; 95% CI, 1.4-6.2]) and chronic obstructive pulmonary disease (death [OR, 2.5; 95% CI, 1.6-3.7], stroke/death [OR, 1.8; 95% CI, 1.4-2.4], and S/D/CE [OR 1.8, 95% CI 1.4-2.3]).

CONCLUSIONS

With 38% of perioperative adverse events after CEA happening posthospitalization, regardless of symptoms status, we need to be alert to the ongoing risks after discharge particularly in women, patients with renal failure, or chronic obstructive pulmonary disease. This emphasizes the need for reporting and comparing 30-day adverse event rates when evaluating outcomes for CEA, or comparing carotid stenting to CEA.

Risk prediction for adverse events after carotid artery stenting in higher surgical risk patients

BACKGROUND AND PURPOSE

The goal of carotid artery stenting is to decrease the risk of stroke or other adverse events from carotid artery disease. Choosing a treatment strategy requires patient-specific information regarding periprocedural risk of adverse neurologic events. The aim of this study was to predict individual patient risk after carotid artery stenting in patients at higher risk for carotid endarterectomy.

METHODS

Subjects enrolled in the Stenting and Angioplasty with Protection in Patients at High-Risk for Endarterectomy (SAPPHIRE) worldwide study underwent carotid artery stenting with distal protection. Only patients with at least 1 anatomic or comorbid factor associated with elevated surgical risk were included. Preprocedural factors were used to develop a model and integer-based risk score predicting stroke or death within 30 days. The model was calibrated and internally validated using bootstrap resampling.

RESULTS

Ten thousand one hundred eighty-six patients were included in the analysis. The overall rate of stroke or death was 3.6% at 30 days after carotid artery stenting. Independent predictors of adverse outcomes were increased age (P=0.006), history of stroke (P<0.001), history of transient ischemic attack presentation (P=0.001), recent (<4 weeks) myocardial infarction (P=0.006), dialysis treatment (P=0.007), need for cardiac surgery in addition to carotid revascularization (P=0.005), a right-sided carotid stenosis (P=0.006), a longer carotid plaque (P=0.012), the presence of a Type II or III aortic arch (P=0.035), and a tortuous carotid arterial system (P=0.004). The optimism-adjusted C-statistic was 0.691.

CONCLUSIONS

Commonly collected clinical and anatomic variables can identify patients at high and low risk for stroke or death after carotid artery stenting.

Carotid artery stent placement

In the past 3 years, there have been significant developments in the field of carotid revascularization, including: 1) the results of a large primary stroke prevention trial; 2) the emergence of novel platforms for emboli protection; 3) improved characterization of the high-risk carotid artery stent (CAS) patient; 4) completion of several very large post-market surveillance (PMS) trials of CAS in high-surgical-risk patients; and 5) the completion of 4 large randomized controlled trials comparing CAS with carotid endarterectomy in average-risk patients. The purpose of this review is to update the current status of revascularization therapies to reduce stroke in patients with extracranial carotid artery disease with a focus on the most recent developments regarding the role of CAS.

Patients Requiring Dialysis are not at Risk of Greater Complication after Carotid Endarterectomy

Stroke is a leading cause of disability and the third leading cause of death. Landmark studies have demonstrated that carotid endarterectomy (CEA) reduced the risk of stroke among selected patients with carotid stenosis. Renal insufficiency is a known risk factor for stroke and appears to be an independent risk factor for poor outcome after CEA. Studies have reported high morbidity and mortality after CEA in patients on dialysis. However, our experience has been that patients undergoing dialysis have no greater risk for a poor outcome. This study was a retrospective review of our CEA patients to ascertain our morbidity and mortality results in dialysis patients versus patients not on dialysis. An institutional retrospective chart review of CEAs from January 1999 to December 2007 was conducted. Patients on dialysis at the time of CEA were identified. Their charts were reviewed for complications 30 days after surgery. This was compared with our total experience with CEAs from January 1999 to December 2007. Of the 28 patients undergoing CEA while dialysis dependent, none had complications in the 30-day postoperative period. This compares favorably with the cohort of all CEAs by the same surgeons. In that group, 13 complications were identified (13 of 1,141). Patients undergoing dialysis are at no greater risk for complications when undergoing carotid endarterectomy than the general population.

The CAPTURE registry: results of carotid stenting with embolic protection in the post approval setting

BACKGROUND

Pivotal study data examining carotid stenting with embolic protection as a less invasive alternative to endarterectomy for high surgical risk patients have been acquired under controlled conditions with highly selected physicians and hospitals. This report examines outcomes of carotid stenting post-approval after diffusion of this technology to a broader cross-section of physicians and hospitals.

METHODS

The Carotid Acculink/Accunet Post-Approval Trial to Uncover Unanticipated or Rare Events (CAPTURE) is a prospective, multi-center registry to assess two important aspects of the post-IDE experience: the safety of carotid stenting by physicians with varying levels of experience as a measure of the adequacy of physician training, and the identification of rare/unexpected device-related complications. The primary endpoint was a composite of death, any stroke, or myocardial infarction within 30 days post-procedure.

RESULTS

3,500 patients were enrolled by 353 physicians at 144 sites. The 30-day primary endpoint event rate was 6.3% (95% CI: 5.5-7.1%) and did not differ among the three operator experience levels (5.3%, 6.0%, and 7.4%; P = 0.31) from most to least experienced, respectively. There were no differences in outcomes among physician specialties when adjusted for case mix. There were no unanticipated device related adverse events.

CONCLUSIONS

The results of the CAPTURE study compare favorably to those achieved in the predicate pivotal investigations, and suggest that the post-approval transfer of this new therapy to the community practice setting via carotid stent training programs is effective in preparing physicians with varying experience levels and specialty training backgrounds.

Adults Undergoing Cardiac Surgery at a Children’s Hospital: An Analysis of Perioperative Morbidity

BACKGROUND

Limited data exist regarding the perioperative morbidity profile of adults who have cardiac operations at pediatric facilities.

METHODS

A retrospective review (January 2000 to December 2004) of patients (aged 18 years or older) who underwent cardiac surgery at our pediatric institution was performed.

RESULTS

There were 149 cardiac operations performed in 135 patients. There were 2 early deaths. There were 70 preoperative noncardiac morbidities in 49 patients (36%) and 140 preoperative cardiac morbidities in 78 patients (58%). Preoperative arrhythmia (n = 76) and moderate or greater ventricular systolic dysfunction (n = 24) were most common. There were 51 postoperative adverse noncardiac events in 32 patients (24%). Renal insufficiency (> 0.5 mg/dL baseline change; n = 8) was most common. There were 53 postoperative adverse cardiac events in 44 patients (33%). Ventricular tachycardia (n = 13) was most common. Risk factors for postoperative adverse noncardiac events included preoperative histories of New York Heart Association (NYHA) class III or greater (p < 0.001), seizure (p = 0.04), and psychiatric disorder (p = 0.002). Risk factors for postoperative adverse cardiac events included older patient age (p = 0.001), preoperative functional single ventricle (p = 0.006), NHYA class III or greater (p = 0.003), atrial fibrillation/flutter (p < 0.001), and ventricular tachycardia or fibrillation (p = 0.04).

CONCLUSIONS

Postoperative adverse events occur frequently when adults undergo cardiac operations at children's hospitals. Older patient age, preoperative arrhythmias, and preoperative NHYA class are predictors of postoperative adverse cardiac events.

Chronic Renal Insufficiency and Risk of Early Mortality in Patients Undergoing Carotid Endarterectomy

We compared early outcome after carotid endarterectomy (CEA) in patients (n = 857 with 1,011 CEA interventions) with and without chronic renal insufficiency (CRI). Two groups were compared: a group with normal renal function (n = 909) and a group with CRI (creatinine >/=1.5 mg/dL and clearance of </=30 mL/min, as well as dialysis and transplant patients, n = 102). Mean age was significantly higher in CRI patients (71.22 vs. 68.33 years, p = 0.001). The incidence of smokers was 53.9% in the non-CRI group vs. 39.2% in CRI patients (p = 0.005). Hypertension (88.2% vs. 75.1, p = 0.003) and cardiac disease (58.8% vs. 47.4%, p = 0.029) were more common in the CRI group. The perioperative mortality rate was significantly higher in CRI patients (3.9% vs. 1.0%, p = 0.013). Multivariate logistic regression analysis showed a significant association between CRI and 30-day death rate (odds ratio = 3.76, p = 0.032). In this series, CRI patients presented an increased mortality. The mortality risk may be related to the increased rates of preoperative hypertension and coronary disease and perioperative myocardial infarction. A more reserved attitude seems indicated in planning CEA for patients with renal dysfunction in combination with a history of coronary artery disease.

The Risk of Carotid Endarterectomy in Patients with Chronic Renal Insufficiency

OBJECTIVE

Carotid endarterectomy (CEA) has been associated with less favorable outcome in patients with chronic renal insufficiency (CRI). The authors compared results of CEA in the presence and absence of CRI at their institution over a 5-year period.

DESIGN/SETTING/PARTICIPANTS

This article is a retrospective review of 1351 patients who underwent CEA between 1998 and 2004. Chronic renal insufficiency was present in 143 patients. Renal insufficiency was graded as mild (creatinine 1.6-2.9 mg/dL) or severe (creatinine > or = 3.0 mg/dL or on hemodialysis). The composite endpoint was stroke or death within 30 days postoperatively. The results were compared with 150 consecutive patients having CEA in the absence of renal insufficiency between 2002 and 2003.

RESULTS

For the 143 patients with CRI, the composite endpoint was 9.0%, whereas the composite endpoint for the 150 control patients without CRI was 2.6% (p = 0.032). For patients with severe CRI (creatinine > or = 3.0 or on hemodialysis), the composite endpoint was 19.0% (p = 0.08). For those with mild CRI (creatinine 1.6-2.9), the composite endpoint was 7.3% (p = 0.06).

CONCLUSIONS

Chronic renal insufficiency is associated with increased incidence of stroke, myocardial infarction, and death after CEA. For patients with advanced CRI, carotid artery stenting (CAS) or aggressive medical management may be alternative treatment options.

Patient selection for carotid stenting versus endarterectomy: A systematic review

Carotid artery stenting has emerged as an alternative to carotid endarterectomy for the treatment of severe extracranial carotid stenosis in patients with anatomic or clinical factors that increase their risk of complications with surgery, yet there remains a substantial amount of variability and uncertainty in clinical practice in the referral of patients for stenting vs endarterectomy. By undertaking a thorough review of the literature, we sought to better define which subsets of patients with "high-risk" features would be likely to preferentially benefit from carotid stenting or carotid endarterectomy. Although only a single randomized trial comparing the outcomes of carotid stenting with distal protection and endarterectomy has been completed, a wealth of observational data was reviewed. Relative to endarterectomy, the results of carotid stenting seem favorable in the setting of several anatomic conditions that render surgery technically difficult, such as restenosis after prior endarterectomy, prior radical neck surgery, and previous radiation therapy involving the neck. The results of stenting are also favorable among patients with severe concomitant cardiac disease. Carotid endarterectomy, alternatively, seems to represent the procedure of choice among patients 80 years of age or older in the absence of other high-risk features. Overall, existing data support the concept that carotid stenting and endarterectomy represent complementary rather than competing modes of therapy. Pending the availability of randomized trial data to help guide procedural selection, which is likely many years away, an objective understanding of existing data is valuable to help select the optimal mode of revascularization therapy for patients with severe carotid artery disease who are at heightened surgical risk.

Protected carotid stenting in high-surgical-risk patients: The ARCHeR results

BACKGROUND

Carotid endarterectomy is the standard of care for most patients with severe extracranial carotid bifurcation disease. However, its safety and efficacy in patients with significant surgical risk are unclear. The ARCHeR (ACCULINK for Revascularization of Carotids in High-Risk patients) trial was performed to determine whether carotid artery stenting with embolic protection is a safe and effective alternative to endarterectomy in high-surgical-risk patients.

METHODS

The ARCHeR trial is a series of three sequential, multicenter, nonrandomized, prospective studies. Forty-eight sites enrolled 581 high-surgical-risk patients between May 2000 and September 2003. Patients with severe carotid artery stenosis (angiographically defined, symptomatic > or =50%, or asymptomatic > or =80%) had an ACCULINK nitinol stent implanted. The ACCUNET filter embolic protection system was added to the procedure in the final 2 studies (422 patients). The primary efficacy end point was a composite of periprocedural (< or =30 days) death, stroke, and myocardial infarction, plus ipsilateral stroke between days 31 and 365.

RESULTS

The 30-day rate of death/stroke/myocardial infarction was 8.3% (95% confidence interval [CI], 6.2%-10.8%), and that of stroke/death was 6.9% (95% CI, 5.0%-9.3%). Most (23/32) strokes were minor, of which more than half (12/23) returned to baseline National Institutes of Health Stroke Scale scores within 30 days. The 30-day major/fatal stroke rate was 1.5% (95% CI, 0.7%-2.9%). No hemorrhagic strokes were observed in the study. Ipsilateral cerebrovascular accident occurred in 1.3% between 30 days and 1 year, thus giving a primary composite end point of 30-day death/stroke/myocardial infarction plus ipsilateral stroke at 1 year of 9.6% (95% CI, 7.2%-12.0%), which is below the 14.4% historical control comparator. Target lesion revascularization at 12 months and 2 years was 2.2% and 2.9%, respectively.

CONCLUSIONS

The ARCHeR results demonstrate that extracranial carotid artery stenting with embolic filter protection is not inferior to historical results of endarterectomy and suggest that carotid artery stenting is a safe, durable, and effective alternative in high-surgical-risk patients.

Uremic bleeding: pathophysiology and clinical risk factors

Renal insufficiency appears clinically to be associated with a bleeding tendency. This has been documented in clinical settings including as a complication of medical interventions such as surgery and also in spontaneous bleeding events at gastrointestinal and intracranial sites. The pathophysiology that underlies this tendency appears to involve platelet dysfunction and an imbalance of mediators of normal endothelial function. It is also may be complicated by the co-morbidities in this population, such as vascular disease, hypertension and anemia, and the medical interventions required to treat such co-morbidities. This article reviews the evidence, the pathophysiology and the risk factors for increased bleeding in patients with chronic renal insufficiency.

Carotid endarterectomy in patients with chronic renal insufficiency: A recent series of 184 cases

BACKGROUND

The published results of carotid endarterectomy (CEA) in chronic renal insufficiency (CRI) patients are contradictory, mostly because of the relatively small number of patients in these studies. To better assess the neurologic complications and mortality, we reviewed a recent and substantially larger series of CRI patients who underwent CEAs.

METHODS

From March 2000 to March 2003, 675 consecutive primary CEAs were performed in 609 patients (346 men, 57%) under general anesthesia. Asymptomatic carotid artery stenosis accounted for 71% of cases. CRI (serum creatinine level > or = 1.5 mg/dL) was detected in 166 patients (27%) who underwent 184 CEAs. The remaining 443 patients (73%) had 491 CEAs.

RESULTS

Patients with CRI were different in age (76 +/- 8 years vs 72 +/- 9 years, P < .001), male gender (73% vs 51%, P < .001), coronary artery disease (50% vs 28%, P < .001), and diabetes mellitus incidence (38% vs 27%, P < .02). No significant difference in stroke rates was observed between the CRI patients and the control group (1.2% vs 0.5%). The mortality rate for CRI patients was 3%, whereas it was 0% for the control group ( P < .002). The 143 CRI patients with serum creatinine levels from 1.5 to 2.9 mg/dL had a 0.7% mortality rate, whereas it was 17% for 23 patients with serum creatinine levels of 3 mg/dL or more ( P < .001). The stroke rate for the former group was 0.7% and 4.3% for the latter group (NS). Asymptomatic (16) and symptomatic (7) patients with serum creatinine levels of 3 mg/dL or more had mortality rates of 13% and 28%, respectively, with P = .6.

CONCLUSION

The high mortality rate observed in patients with serum creatinine levels of 3 mg/dL or more after CEA calls for a nonoperative approach in the management of asymptomatic patients.

Effect of chronic kidney disease on outcomes after carotid artery stenting

We performed a single-center retrospective analysis evaluating the effect of chronic kidney disease among patients who underwent carotid artery stenting. The presence of chronic kidney disease is associated with higher periprocedural and 6-month death, stroke, or myocardial infarction after carotid artery stenting.

Recurrent Stenosis and Contralateral Occlusion: High-risk Situations in Carotid Endarterectomy?

Carotid angioplasty and stenting (CAS) has been proposed as a treatment option for carotid occlusive disease in high-risk patients including those with recurrent stenosis (RS) and contralateral occlusion (CO). This study reviews the results of carotid endarterectomy (CEA) in patients with RS and CO. We conducted a retrospective review from our vascular registry of 1670 patients who underwent CEAs ( n = 1950) from January 1990 through December 2001. Procedures included RS 86 (4.4%), CO 112 (5.7%), and control 1752 (89.9%). There were 37 strokes in the entire group (1.9%). Among the high-risk group with RS and CO, there were 6 strokes, (RS n = 2, CO n = 4) 3%. There were 31 strokes in the control group 1.8% ( p = NS). Postoperative TIAs were observed more frequently in patients with CO ( n = 2) or RS ( n = 2), 1.8% and 2.3%, respectively ( p < 0.05). Neck hematomas, intracerebral hemorrhages, and myocardial infarctions did not differ between groups. Three deaths occurred within 30 days (0.15%); one was a patient with CO. Renal failure and symptomatic disease were each associated with a higher risk of perioperative stroke; among patients with renal failure there were 6 strokes (4.6%) p < 0.05, in symptomatic patients there were 26 strokes (2.7%) p < 0.05. Multivariate logistic regression analysis confirmed that preoperative renal disease and surgery for symptomatic disease were both significant predictors of perioperative stroke ( p < 0.05; odds ratio 2.177 and 2.943 respectively) while neither RS nor CO was from these results we concluded that the presence of RS and CO do not increase the risk of perioperative stroke in CEA.

The case against routine preoperative laboratory testing

In this article, we have shown that almost all "routine" laboratory tests before surgery have limited clinical value. Clinicians should order only a small number of routine tests based on age as noted in Table 13. Selective use of other preoperative tests should be based on history and physical examination findings that identify subgroups of patients who are more likely to have abnormal results. In general, clinicians should order tests only if the outcome of an abnormal test will influence management. When an abnormal test results from such testing, it is critical that physicians document their thinking about the result. Most routine preoperative tests are neither expensive nor risky. For this reason, clinicians can have a low threshold for ordering these tests in patients for whom the frequency of abnormalities is increased compared with a healthy population. We believe that physicians should not be criticized for selective test ordering before surgery. Physicians and institutions recommending routine preoperative testing for all patients provide no clinical value to their patients at considerable cost.

Gender and carotid endarterectomy: does it matter?

OBJECTIVE

Multiple large series have retrospectively identified female gender as a risk factor for perioperative stroke and death after carotid endarterectomy (CEA).

METHODS

Data for all patients who underwent CEA at a single institution from January 1990 to December 1998 were entered into a computerized vascular registry and form the basis of this report.

RESULTS

A total of 1298 CEA procedures were performed, of which 520 (40%) were in women and 778 (60%) in men. The mean age was 69.8 +/- 8.7 years for men and 71.2 +/- 8.5 years for women (P <.001). Cardiac risk factors significantly varied among the two groups, with women more likely to have diabetes (42% vs 36%) and hypertension (77% vs 66%), whereas tobacco history was higher among men (85% vs 71%) (P <.05 for all). Female patients were more likely to be asymptomatic at presentation (men, 44% vs women, 51%; P =.022). Postoperative myocardial infarction occurred in eight patients (0.6%) with no differences between men (0.4%) and women (1.0%) (P = not significant). For all adverse postoperative cardiac events (myocardial infarction, congestive heart failure, or arrhythmia), the incidence was 1.9% (25 patients), again with no differences between men (1.5%) and women (2. 5%) (P = not significant). There were 25 postoperative neurologic events (19 strokes, six transient ischemic attacks) among the entire cohort (1.9%), of which 16 were in men (2.1%) and nine in women (1. 6%; P = not significant). The overall postoperative stroke rate was 1.5% (13 [1.7%] of 778 men; 6 [1.2%;] of 520 women; P = not significant). Total operative mortality was 0.3% (3 [0.4%] of 778 men; 1 [0.2%] of 778 women; P = not significant). Late recurrent stenosis requiring operation developed in 14 patients (1.1%) during follow-up (6 [0.8%] of 778 men; 8 [1.5%] of 520 women; P =.19).

CONCLUSIONS

Although there is significant variability in cardiac risk factors and presentation, female gender is not a risk factor for stroke, death, or cardiac morbidity after CEA. Women are not at higher risk for reoperation for recurrent stenosis.