Early invasive treatment benefits patients with renal dysfunction in unstable coronary artery disease

Prophylactic hemodialysis following coronary angiography and one-year outcomes in non-dialysis patients with chronic kidney disease: A propensity-matched study

BACKGROUND/PURPOSE

Prophylactic hemodialysis after coronary angiography in patients with chronic kidney disease (CKD) prevents contrast nephropathy; however, the one-year outcomes are unclear. This study aimed to investigate the one-year outcomes of prophylactic hemodialysis against standard treatment in patients with CKD who underwent coronary angiography.

METHODS

A cohort study of 359 patients with CKD, coronary artery disease (CAD), and serum creatinine levels of 176.8-530.4 μmol/L, who were referred for elective coronary angiography was conducted. Propensity score matching identified 118 patient pairs for outcome comparisons. The hemodialysis group underwent prophylactic hemodialysis after coronary angiography, whereas the control group received standard treatment. The study's primary outcome was free from dialysis was considered the primary outcome, whereas the secondary outcome was overall survival. Unadjusted estimates of the probability of free from dialysis and overall survival were computed using Kaplan-Meier survival curves and log-rank tests. Cox proportional-hazards regression models were used in determining the risk factors associated with ESRD and mortality.

RESULTS

During a mean 9.3 months follow-up duration, the hemodialysis group had significantly better free from dialysis (85.6% vs. 64.4%; P = 0.002) and overall survival (85.4% vs. 78.5%; P = 0.008) rates than the control group. Cox proportional-hazards regression analyses of the propensity score-matched patients showed that the hemodialysis group had reduced risks for ESRD and mortality (hazard ratios, 0.32 and 0.48, respectively).

CONCLUSION

Prophylactic Hemodialysis following coronary angiography was associated with reduced ESRD and mortality risks in CKD patients with CAD, who did not routinely undergo dialysis.

Routine invasive strategies versus selective invasive strategies for unstable angina and non-ST elevation myocardial infarction in the stent era

BACKGROUND

People with unstable angina and non-ST elevation myocardial infarction (UA/NSTEMI) are managed with a combination of medical therapy, invasive angiography and revascularisation. Specifically, two approaches have evolved: either a 'routine invasive' strategy whereby all patients undergo coronary angiography shortly after admission and, if indicated, coronary revascularisation; or a 'selective invasive' (also referred to as 'conservative') strategy in which medical therapy alone is used initially, with a selection of patients for angiography based upon evidence of persistent myocardial ischaemia. Uncertainty exists as to which strategy provides the best outcomes for these patients. This Cochrane review is an update of a Cochrane review originally published in 2006, to provide a robust comparison of these two strategies in the early management of patients with UA/NSTEMI.

OBJECTIVES

To determine the benefits and harms associated with the following.1. A routine invasive versus a conservative or 'selective invasive' strategy for the management of UA/NSTEMI in the stent era.2. A routine invasive strategy with and without glycoprotein IIb/IIIa receptor antagonists versus a conservative strategy for the management of UA/NSTEMI in the stent era.

SEARCH METHODS

We searched the following databases and additional resources up to 25 August 2015: the Cochrane Central Register of Controlled Trials (CENTRAL) on the Cochrane Library, MEDLINE and EMBASE, with no language restrictions.

SELECTION CRITERIA

We included prospective randomised controlled trials (RCTs) that compared invasive with conservative or 'selective invasive' strategies in participants with acute UA/NSTEMI.

DATA COLLECTION AND ANALYSIS

Two review authors screened the records and extracted data in duplicate. Using intention-to-treat analysis with random-effects models, we calculated summary estimates of the risk ratio (RR) with 95% confidence intervals (CIs) for the primary endpoints of all-cause death, fatal and non-fatal myocardial infarction (MI), combined all-cause death or non-fatal MI, refractory angina and re-hospitalisation. We performed further analysis of included studies based on whether glycoprotein IIb/IIIa receptor antagonists were used routinely. We assessed the heterogeneity of included trials using Pearson χ² (Chi² test) and variance (I² statistic) analysis. Using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, we assessed the quality of the evidence and the GRADE profiler (GRADEPRO) was used to import data from Review Manager 5.3 (Review Manager) to create Summary of findings (SoF) tables.

MAIN RESULTS

Eight RCTs with a total of 8915 participants (4545 invasive strategies, 4370 conservative strategies) were eligible for inclusion. We included three new studies and 1099 additional participants in this review update. In the all-study analysis, evidence did not show appreciable risk reductions in all-cause mortality (RR 0.87, 95% CI 0.64 to 1.18; eight studies, 8915 participants; low quality evidence) and death or non-fatal MI (RR 0.93, 95% CI 0.71 to 1.2; seven studies, 7715 participants; low quality evidence) with invasive strategies compared to conservative (selective invasive) strategies at six to 12 months follow-up. There was appreciable risk reduction in MI (RR 0.79, 95% CI 0.63 to 1.00; eight studies, 8915 participants; moderate quality evidence), refractory angina (RR 0.64, 95% CI 0.52 to 0.79; five studies, 8287 participants; moderate quality evidence) and re-hospitalisation (RR 0.77, 95% CI 0.63 to 0.94; six studies, 6921 participants; moderate quality evidence) with routine invasive strategies compared to conservative (selective invasive) strategies also at six to 12 months follow-up.Evidence also showed increased risks in bleeding (RR 1.73, 95% CI 1.30 to 2.31; six studies, 7584 participants; moderate quality evidence) and procedure-related MI (RR 1.87, 95% CI 1.47 to 2.37; five studies, 6380 participants; moderate quality evidence) with routine invasive strategies compared to conservative (selective invasive) strategies.The low quality evidence were as a result of serious risk of bias and imprecision in the estimate of effect while moderate quality evidence was only due to serious risk of bias.

AUTHORS' CONCLUSIONS

In the all-study analysis, the evidence failed to show appreciable benefit with routine invasive strategies for unstable angina and non-ST elevation MI compared to conservative strategies in all-cause mortality and death or non-fatal MI at six to 12 months. There was evidence of risk reduction in MI, refractory angina and re-hospitalisation with routine invasive strategies compared to conservative (selective invasive) strategies at six to 12 months follow-up. However, routine invasive strategies were associated with a relatively high risk (almost double the risk) of procedure-related MI, and increased risk of bleeding complications. This systematic analysis of published RCTs supports the conclusion that, in patients with UA/NSTEMI, a selectively invasive (conservative) strategy based on clinical risk for recurrent events is the preferred management strategy.

Early-invasive strategies for the management of coronary heart disease in chronic kidney disease: is acute kidney injury a consideration?

PURPOSE OF REVIEW

People with chronic kidney disease (CKD) are less likely to receive early-invasive management of acute coronary syndrome (ACS). The purpose of this article is to review the risks and outcomes of early-invasive versus conservative strategies, and to consider how contrast-induced acute kidney injury (CI-AKI) should factor in treatment decisions for people with CKD.

RECENT FINDINGS

Numerous observational studies have characterized the prognostic importance of CI-AKI. However, recent studies illustrate that compared to the risk of AKI in individuals treated conservatively, the additional risk of kidney injury associated with invasive coronary procedures is relatively modest. Despite the risk of CI-AKI, early-invasive management of ACS has been associated with important long-term benefits.

SUMMARY

These findings illustrate that the additional short-term risk of AKI associated with invasive management should be considered alongside long-term treatment effects on other clinical outcomes and should not act as a deterrent to their use. Strategies to increase the uptake of an invasive management approach, accompanied by the use of CI-AKI prevention strategies, could benefit high-risk individuals with CKD.

Clinical features, use of evidence-based therapies, and cardiovascular outcomes among patients with chronic kidney disease following non-ST-elevation acute coronary syndrome

BACKGROUND

Chronic kidney disease (CKD) is associated with an increased risk of cardiovascular events following acute coronary syndrome (ACS). The underlying pathobiology and optimal treatments for this population continue to be evaluated.

HYPOTHESIS

Patients with CKD will receive fewer evidence-based therapies and experience high rates of adverse cardiovascular events in both the short- and long term.

METHODS

The MERLIN-TIMI 36 (Metabolic Efficiency With Ranolazine for Less Ischemia in Non-ST-Elevation Acute Coronary Syndromes-Thrombolysis in Myocardial Infarction 36) trial randomized non-ST-elevation ACS patients to ranolazine or placebo, with no exclusion for renal dysfunction (except dialysis). We conducted a prespecified analysis among 6543 patients based on the degree of CKD.

RESULTS

Patients with worse renal function were older with more comorbidities (P < 0.0001 for each). They were less likely to receive evidence-based cardiovascular medicines (P < 0.04 for each). Rates of an early invasive management strategy varied based on renal function; however, among patients with the highest TIMI risk scores, the rates of an early invasive management strategy were similar regardless of glomerular filtration rate (GFR) (Pinteraction = 0.005). Lower GFR was associated with increased rates of cardiovascular disease or myocardial infarction in the short and long term, even after adjustment (GFR <30 vs ≥90 mL/min/1.73 m(2) ; hazard ratio [HR]: 3.24 [95% confidence interval {CI}: 1.26-8.38] through 7 days and HR: 2.12 [95% CI: 1.33-3.39] through 1 year). The effect of ranolazine vs placebo on clinical outcomes was similar among those with and without CKD (Pinteraction = not significant).

CONCLUSIONS

Following ACS, patients with renal dysfunction had more cardiovascular risk factors but were less likely to receive evidence-based medical therapies. A strong graded, independent relationship between the degree of CKD and poor clinical outcomes was observed over time. Continued efforts to optimize ACS treatment strategies in patients with CKD are warranted.

Renal outcomes associated with invasive versus conservative management of acute coronary syndrome: propensity matched cohort study

OBJECTIVES

To examine the association of early invasive management of acute coronary syndrome with adverse renal outcomes and survival, and to determine whether the risks or benefits of early invasive management differ in people with pre-existing chronic kidney disease.

DESIGN

Propensity score matched cohort study.

SETTING

Acute care hospitals in Alberta, Canada, 2004-09.

PARTICIPANTS

10,516 adults with non-ST elevation acute coronary syndrome.

INTERVENTIONS

Participants were stratified by baseline estimated glomerular filtration rate and matched 1:1 on their propensity score for early invasive management (coronary catheterisation within two days of hospital admission).

MAIN OUTCOME MEASURES

Risks of acute kidney injury, kidney injury requiring dialysis, progression to end stage renal disease, and all cause mortality were compared between those who received early invasive treatment versus conservative treatment.

RESULTS

Of 10,516 included participants, 4276 (40.7%) received early invasive management. After using propensity score methods to assemble a matched cohort of conservative management participants with characteristics similar to those who received early invasive management (n=6768), early invasive management was associated with an increased risk of acute kidney injury (10.3% v 8.7%, risk ratio 1.18, 95% confidence interval 1.03 to 1.36; P=0.019), but no difference in the risk of acute kidney injury requiring dialysis (0.4% v 0.3%, 1.20, 0.52 to 2.78; P=0.670). Over a median follow-up of 2.5 years, the risk of progression to end stage renal disease did not differ between the groups (0.3 v 0.4 events per 100 person years, hazard ratio 0.91, 95% confidence interval 0.55 to 1.49; P=0.712); however, early invasive management was associated with reduced long term mortality (2.4 v 3.4 events per 100 person years, 0.69, 0.58 to 0.82; P<0.001). These associations were consistent among people with pre-existing reduced estimated glomerular filtration rate and with alternate definitions for early invasive management.

CONCLUSIONS

Compared with conservative management, early invasive management of acute coronary syndrome is associated with a small increase in risk of acute kidney injury but not dialysis or long term progression to end stage renal disease.

Optimal strategy of coronary revascularization in chronic kidney disease patients: a meta-analysis

BACKGROUND

Patients with chronic kidney disease (CKD) have high risks of coronary artery disease (CAD). Coronary revascularization is beneficial for long-term survival, but the optimal strategy remains still controversial.

METHODS

We searched studies that have compared percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) for revascularization of the coronary arteries in CKD patients. Short-term (30 days or in-hospital) mortality, long-term (at least 12 months) all-cause mortality, cardiac mortality and the incidence of late myocardial infarction and recurrence of revascularization were estimated.

RESULTS

28 studies with 38,740 patients were included. All were retrospective studies from 1977 to 2012. Meta-analysis showed that PCI group had lower short-term mortality (OR 0.55, 95% CI 0.41 to 0.73, P<0.01), but had higher long-term all-cause mortality (OR 1.29, 95% CI 1.23 to 1.35, P<0.01). Higher cardiac mortality (OR 1.08, 95% CI 1.01 to 1.15, P<0.05), higher incidence of late myocardial infarction (OR 1.78, 95% CI 1.65 to 1.91, P<0.01) and recurring revascularization rate (OR 2.94, 95%CI 2.15 to 4.01, P<0.01) is found amongst PCI treated patients compared to CABG group.

CONCLUSIONS

CKD patients with CAD received CABG had higher risk of short-term mortality but lower risks of long-term all-cause mortality, cardiac mortality and late myocardial infarction compared to PCI. This could be due to less probable repeated revascularization.

Decline in 20-year mortality after myocardial infarction in patients with chronic kidney disease: evolution from the prethrombolysis to the percutaneous coronary intervention era

Cardiovascular disease is the main cause of death in patients with chronic kidney disease (CKD). Here we measured temporal trends in treatment and mortality after myocardial infarction (MI) depending on kidney function at presentation in 12,087 patients admitted for MI to a coronary care unit from 1985 to 2008. The patients were categorized into those with normal kidney function (estimated glomerular filtration rate over 90 ml/min per 1.73 m(2)), and those with CKD as defined by Kidney Foundation practice guidelines, with 8632 patients (71%) at CKD stages 2-5. Use of evidence-based care increased over time in all CKD stages. Mortality rates fell over the entire time period. When comparing data from 2000-2008 to that from 1985-1990, adjusted 30-day mortality fell both in patients with CKD stages 4-5 (adjusted odds 0.33, 95% confidence interval 0.18-0.60) and in those without kidney impairment (adjusted odds 0.21, 95% confidence interval 0.10-0.42). This mortality decrease was sustained during long-term follow-up. There was no significant interaction between kidney function and decade of admission. Overall, median survival was over 20, 15, 8, and 1.8 years for patients with normal kidney function, stage 2, stage 3, and stage 4-5 CKD, respectively. Thus, during the past 25 years, treatment of patients with a MI improved substantially with a concomitant decline in mortality. Although our findings were similar for all stages of kidney function, the prognosis remains poor for patients with stage 4-5 CKD.

Management of acute coronary syndrome in patients with chronic kidney disease: if we don't risk anything, we risk even more

The utilization of coronary angiography and percutaneous coronary intervention in the routine care for patients with acute coronary syndromes (ACS) has resulted in significant improvement in their prognosis. Consequently, recommendations on the use of these management strategies are reflected in the ACC/AHA guidelines for the management of patients with unstable angina and myocardial infarction. However, among other causes, the 'phobia' of nephrotoxicity of iodinated contrast media (ICM) in chronic kidney disease (CKD) patients and its claimed adverse effect on short-term and long-term survival has led to a worryingly low use of ICM-based diagnostic and therapeutic interventions in patients with CKD. We argue that the fear of iodinated contrast media-induced acute kidney injury (ICI-AKI) is not a valid reason to avoid ICM-based investigations/interventions in CKD patients with ACS; the risks of myocardial infarction and death greatly outweigh the risk of ICI-AKI in most of these patients and hence they should always be considered for myocardial revascularization.

Bridging the gender gap: Insights from a contemporary analysis of sex-related differences in the treatment and outcomes of patients with acute coronary syndromes

BACKGROUND

The question of whether gender-related disparities still exist in the treatment and outcomes of patients presenting with acute coronary syndromes (ACS) remains controversial. Using data from 4 registries spanning a decade, we sought to determine whether sex-related differences have persisted over time and to examine the treating physician's rationale for adopting a conservative management strategy in women compared with men.

METHODS

From 1999 to 2008, 14,196 Canadian patients with non-ST-segment elevation ACS were recruited into the Acute Coronary Syndrome I (ACSI), ACSII, Global Registry of Acute Coronary Events (GRACE/GRACE(2)), and Canadian Registry of Acute Coronary Events (CANRACE) prospective multicenter registries.

RESULTS

Women in the study population were found to be significantly older than men and were more likely to have a history of heart failure, diabetes, or hypertension. Fewer women were treated with thienopyridines, heparin, and glycoprotein IIb/IIIa inhibitors compared with men in GRACE and CANRACE. Female gender was independently associated with a lower in-hospital use of coronary angiography (adjusted odds ratio 0.76, 95% CI 0.69-0.84, P < .001) and higher in-hospital mortality (adjusted odds ratio 1.26, 95% CI 1.02-1.56, P = .036), irrespective of age (P for interaction =.76). Underestimation of patient risk was the most common reason for not pursuing an invasive strategy in both men and women.

CONCLUSIONS

Despite temporal increases in the use of invasive cardiac procedures, women with ACS are still more likely to be treated conservatively, which may be due to underestimation of patient risk. Furthermore, they have worse in-hospital outcomes. Greater awareness of this paradox may assist in bridging the gap between current guidelines and management practices.

Management of non-ST-segment elevation acute myocardial infarction in patients with chronic kidney disease (from the Korea Acute Myocardial Infarction Registry)

The aim of this study was to compare clinical outcomes among early invasive (EI), deferred invasive (DI), and conservative strategies in patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) and chronic kidney disease (CKD). High-risk patients with NSTEMI are believed to fare better with an EI strategy, but the optimal treatment for patients with NSTEMI and CKD is not known. In total 5,185 patients with acute NSTEMI were enrolled from the Korea Acute Myocardial Infarction Registry and followed for 1 year. Patients were divided into EI, DI, and conservative treatment groups and classified into 4 stages using references from the National Kidney Foundation. The invasive EI and DI groups were compared to the conservative groups, and the EI and DI groups were compared according to each renal function stage. At 1-year follow-up, mortality rates in the conservative group were significantly higher than in the invasive groups except for the severe CKD group. The benefit of the EI over the DI strategy, although there were no significant differences between the 2 groups, tended to decrease as renal function decreased. In conclusion, in the management of NSTEMI, an invasive strategy decreased mortality compared to a conservative strategy except for severe CKD. In the timing of an invasive strategy, the EI strategy was observed to be superior to the DI strategy in patients with mild CKD; however, this tendency reversed as renal function decreased. When patients with NSTEMI have severe CKD, a conservative or DI strategy with prescription of cardioprotective medications and prevention of further deterioration in renal function should be considered.

Early invasive versus conservative strategies for unstable angina and non-ST elevation myocardial infarction in the stent era

BACKGROUND

In patients with unstable angina and non-ST elevation myocardial infarction (UA/NSTEMI) two strategies are possible, either a routine invasive strategy where all patients undergo coronary angiography shortly after admission and, if indicated, coronary revascularization; or a conservative strategy where medical therapy alone is used initially, with selection of patients for angiography based on clinical symptoms or investigational evidence of persistent myocardial ischemia.

OBJECTIVES

To determine the benefits of an invasive compared to conservative strategy for treating UA/NSTEMI in the stent era.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 1), MEDLINE and EMBASE were searched (1996 to February 2008) with no language restrictions.

SELECTION CRITERIA

Included studies were prospective trials comparing invasive with conservative strategies in UA/NSTEMI.

DATA COLLECTION AND ANALYSIS

We identified five studies (7818 participants). Using intention-to-treat analysis with random-effects models, summary estimates of relative risk (RR) with 95% confidence interval (CI) were determined for primary end-points of all-cause death, fatal and non-fatal myocardial infarction, all-cause death or non-fatal myocardial infarction, and refractory angina. Further analysis of included studies was undertaken based on whether glycoprotein IIb/IIIa receptor antagonists were used routinely. Heterogeneity was assessed using Chi(2) and variance (I(2) statistic) methods.

MAIN RESULTS

In the all-study analysis, mortality during initial hospitalization showed a trend to hazard with an invasive strategy (RR 1.59, 95% CI 0.96 to 2.64). The invasive strategy did not reduce death on longer-term follow up. Myocardial infarction rates assessed at 6 to 12 months (5 trials) and 3 to 5 years (3 trials) were significantly decreased by an invasive strategy (RR 0.73, 95% CI 0.62 to 0.86; and RR 0.78, 95% CI 0.67 to 0.92 respectively). The incidence of early (< 4 month) and intermediate (6 to 12 month) refractory angina were both significantly decreased by an invasive strategy (RR 0.47, 95% CI 0.32 to 0.68; and RR 0.67, 95% CI 0.55 to 0.83 respectively), as were early and intermediate rehospitalization rates (RR 0.60, 95% CI 0.41to 0.88; and RR 0.67, 95% CI 0.61 to 0.74 respectively). The invasive strategy was associated with a two-fold increase in the RR of peri-procedural myocardial infarction (as variably defined) and a 1.7-fold increase in the RR of (minor) bleeding with no hazard of stroke.

AUTHORS' CONCLUSIONS

Compared to a conservative strategy for UA/NSTEMI, an invasive strategy is associated with reduced rates of refractory angina and rehospitalization in the shorter term and myocardial infarction in the longer term. However, the invasive strategy is associated with a doubled risk of procedure-related heart attack and increased risk of bleeding and procedural biomarker leaks. Available data suggest that an invasive strategy may be particularly useful in those at high risk for recurrent events.

End-Stage Renal Disease and Sudden Cardiac Death

Patients with end-stage renal disease (ESRD) are at a high risk for sudden cardiac death (SCD). SCD is the most common cause of death in this population and, as in the general population, ventricular arrhythmias seem to be the most common cause of SCD. The increased risk of SCD in ESRD is likely due to factors that are unique to the metabolic derangements associated with this state, as well as the increased prevalence of traditional risk factors. Despite this, the evidence base for the assessment and management of SCD in these patients is limited. This article reviews the current data on underlying risk factors for SCD in patients with ESRD, the role of common medical and device-based therapies for the prevention and treatment of SCD, and the applicability of common methods of risk stratification to patients with ESRD.

Review article: Coronary artery stenoses: detection and revascularization in renal disease

Cardiovascular events are markedly elevated in those with all degrees of renal impairment compared to the general population. There are well established guidelines in the general population for the management of coronary artery disease, however, similar guidelines have not been established in the renal population. This review examines the current published work on the detection of coronary artery stenoses in addition to summarizing the outcomes of revascularization in patients with kidney disease. Testing for coronary artery disease in the renal population most commonly occurs in dialysis patients as part of their assessment for renal transplantation. While a positive myocardial stress test for the detection of significant coronary artery stenoses is associated with an increased risk of cardiac events, there is no clear information currently showing that cardiovascular testing itself reduces the rate of adverse cardiac events after transplantation. Revascularization of coronary artery stenoses is associated with higher morbidity and mortality in all groups with kidney disease than in the general population, with the exception of renal transplant recipients where the mortality is likely to be similar to that of the general population. There appears to be a benefit in coronary artery bypass surgery compared to percutaneous intervention in those on dialysis and after renal transplant. Currently, there is little data to support coronary artery intervention prior to transplantation in those with asymptomatic coronary artery disease.

Influence of renal function on the effects of early revascularization in non-ST-elevation myocardial infarction: data from the Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART)

BACKGROUND

It is unknown whether patients with non-ST-elevation myocardial infarction derive a similar benefit from an early invasive therapy at different levels of renal function.

METHODS AND RESULTS

A total of 23 262 consecutive non-ST-elevation myocardial infarction patients <or=80 years old were included in a nationwide coronary care unit register between 2003 and 2006. Glomerular filtration rate (eGFR) was estimated with the Modification of Diet in Renal Disease Study formula. Patients were divided into medically or invasively treated groups if revascularized within 14 days of admission. A propensity score for the likelihood of invasive therapy was calculated. A Cox regression model with adjustment for propensity score and discharge medication was used to assess the association between early revascularization and 1-year mortality across renal function stages. There was a gradient, with significantly fewer patients treated invasively with declining renal function: eGFR >or=90 mL . min(-1) . 1.73 m(-2), 62%; eGFR 60 to 89 mL . min(-1) . 1.73 m(-2), 55%; eGFR 30 to 59 mL . min(-1) . 1.73 m(-2), 36%; eGFR 15 to 29 mL . min(-1) . 1.73 m(-2), 14%; and eGFR <15 mL . min(-1) . 1.73 m(-2)/dialysis, 15% (P<0.001). After adjustment, the overall 1-year mortality was 36% lower (hazard ratio 0.64, 95% confidence interval 0.56 to 0.73, P<0.001) with an invasive strategy. The magnitude of survival difference was similar in normal-to-moderate renal function groups. The lower mortality observed with invasive therapy declined with lower renal function, with no difference in mortality in patients with kidney failure (eGFR <15 mL . min(-1) . 1.73 m(-2)) or in those receiving dialysis (hazard ratio 1.61, 95% confidence interval 0.84 to 3.09, P=0.15).

CONCLUSIONS

Early invasive therapy is associated with greater 1-year survival in patients with non-ST-elevation myocardial infarction and mild-to-moderate renal insufficiency, but the benefit declines with lower renal function, and is less certain in those with renal failure or on dialysis.

Early angiography in patients with chronic kidney disease: a collaborative systematic review

BACKGROUND AND OBJECTIVES

In the general population, an early invasive strategy of routine coronary angiography is superior to a conservative strategy of selective angiography in patients who are admitted with unstable angina or non-ST segment elevation myocardial infarction (MI), but the effectiveness of this strategy in individuals with chronic kidney disease (CKD) is uncertain.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a collaborative meta-analysis with data provided by the main authors of identified trials to estimate the effectiveness of early angiography in patients with CKD. The Cochrane, Medline, and EMBASE databases were searched to identify randomized trials that compared invasive and conservative strategies in patients with unstable angina or non-ST MI. Pooled risks ratios were estimated using data from enrolled patients with estimated GFR <60 ml/min per 1.73 m(2).

RESULTS

Five randomized trials that enrolled 1453 patients with CKD were included. An early invasive strategy was associated with nonsignificant reductions in all-cause mortality, nonfatal MI, and a composite of death or nonfatal MI. The invasive strategy significantly reduced rehospitalization.

CONCLUSIONS

This collaborative study suggests that the benefits of an early invasive strategy are preserved in patients with CKD and that an early invasive approach reduces the risk for rehospitalization and is associated with trends of reduction in the risk for death and nonfatal re-infarction in patients with CKD. Coronary angiography should be considered for patients who have CKD and are admitted with non-ST elevation acute coronary syndromes.

Cystatin C for enhancement of risk stratification in non-ST elevation acute coronary syndrome patients with an increased troponin T

BACKGROUND

We assessed the value of cystatin C for improvement of risk stratification in patients with non-ST elevation acute coronary syndrome (nSTE-ACS) and increased cardiac troponin T (cTnT), and we compared the long-term effects of an early invasive treatment strategy (EIS) with a selective invasive treatment strategy (SIS) with regard to renal function.

METHODS

Patients (n = 1128) randomized to an EIS or an SIS in the ICTUS trial were stratified according to the tertiles of the cystatin C concentration at baseline. The end points were death within 4 years and spontaneous myocardial infarction (MI) within 3 years.

RESULTS

Mortality was 3.4%, 6.2%, and 13.5% in the first, second, and third tertiles, respectively, of cystatin C concentration (log-rank P < 0.001), and the respective rates of spontaneous MI were 5.5%, 7.5%, and 9.8% (log-rank P = 0.03). In a multivariate Cox regression analysis, the cystatin C concentration in the third quartile remained independently predictive of mortality [hazard ratio (HR), 2.04; 95% CI, 1.02-4.10; P = 0.04] and spontaneous MI (HR, 1.95; 95% CI, 1.05-3.63; P = 0.04). The mortality rate in the second tertile was lower with the EIS than with the SIS (3.8% vs 8.7%). In the third tertile, the mortality rates with the EIS and the SIS were, respectively, 15.0% and 12.2% (P for interaction = 0.04). Rates of spontaneous MI were similar for the EIS and the SIS within cystatin C tertiles (P for interaction = 0.22).

CONCLUSIONS

In patients with nSTE-ACS and an increased cTnT concentration, mild to moderate renal dysfunction is associated with a higher risk of death and spontaneous MI. Use of cystatin C as a serum marker of renal function may improve risk stratification.

Temporal management patterns and outcomes of non-ST elevation acute coronary syndromes in patients with kidney dysfunction

AIMS

To examine: (i) the temporal changes in the management pattern; (ii) the reasons for any treatment disparities; (iii) the relationship between invasive treatment and outcome, among acute coronary syndrome (ACS) patients with vs. without kidney dysfunction.

METHODS AND RESULTS

Canadian ACS I, ACS II registries and Global Registry of Acute Coronary Events (GRACE) were prospective, multi-centre, observational studies of patients with ACS. From 1999 to 2007, non-ST elevation (NSTE) ACS patients were recruited in ACS I (n = 3295; 1999-2001), ACS II (n = 1956; 2002-2003), and GRACE (n = 6491; 2004-2007) in Canada. Using the four-variable Modified Diet in Renal Disease equation, we stratified the study population (n = 11,377) into three groups based on their estimated glomerular filtration rate (eGFR), and examined their treatment and outcome. While in-hospital use of coronary angiography and revascularization increased over time in all groups (P < 0.001), patients with kidney dysfunction were less likely to undergo invasive management (P < 0.001). Unadjusted 1 year mortality was lower among patients receiving in-hospital coronary angiography within all eGFR categories (> or =60 mL/min/1.73 m(2): 2.5 vs. 7.6%, P < 0.001; 30-59 mL/min/1.73 m(2): 8.0 vs. 14.6%, P < 0.001; <30 mL/min/1.73 m(2): 27.5 vs. 41.5%, P = 0.043). In-hospital revascularization was independently associated with lower 1-year mortality (adjusted OR = 0.52, 95% CI 0.36-0.77, P = 0.001), irrespective of eGFR (P for heterogeneity = 0.39). Underestimation of patient risk was the most common barrier to an invasive treatment strategy.

CONCLUSION

Despite temporal increases in invasive management of NSTE-ACS, patients with kidney dysfunction are more commonly treated conservatively, with an associated worse outcome. In-hospital revascularization was independently associated with improved survival, irrespective of eGFR. Randomized controlled trials involving patients with kidney dysfunction are needed to confirm whether more aggressive treatment will improve their poor outcome.

Impact of optimal medical therapy and revascularization on outcome of patients with chronic kidney disease and on dialysis who presented with acute coronary syndrome

Coronary artery disease is the main cause of death in patients with chronic kidney disease (CKD). The poor prognosis associated with acute coronary syndrome (ACS) in these patients has been related to therapeutic nihilism. This study included 2,357 patients with ACS who had percutaneous coronary intervention. According to their creatinine clearance and medical history, they were divided into 3 groups: dialysis (n = 73); CKD (n= 293); and control (n= 1,991). Rates of cardiovascular events were recorded during a 1-year follow-up period. Patients in all groups received similar contemporary therapy for ACS, including percutaneous coronary intervention and optimal medial therapy. On admission, patients with CKD and patients on dialysis more often presented with cardiogenic shock (p = 0.05 and 0.02, respectively). A graded increase in the rate of major adverse cardiovascular events at 1 year was observed with decreasing renal function (control 13%, CKD 22.9%, dialysis 45.2%, p <0.001 for all comparisons). In multivariate analysis, patients with CKD and on dialysis were significantly associated with 1-year major adverse cardiac events with adjusted hazard ratios of, respectively, 1.5 (95% confidence interval 1.1 to 2.1; p = 0.009) and 2.7 (95% confidence interval 1.7 to 4.1; p <0.001). In conclusion, despite optimal contemporary medical therapy and revascularization, the prognosis of patients with CKD and, in particular, of patients undergoing dialysis, remains poor.

Growth differentiation factor 15 for risk stratification and selection of an invasive treatment strategy in non ST-elevation acute coronary syndrome

BACKGROUND

An invasive treatment strategy improves outcome in patients with non-ST-elevation acute coronary syndrome at moderate to high risk. We hypothesized that the circulating level of growth differentiation factor 15 (GDF-15) may improve risk stratification.

METHODS AND RESULTS

The Fast Revascularization during InStability in Coronary artery disease II (FRISC-II) trial randomized patients with non-ST-elevation acute coronary syndrome to an invasive or conservative strategy with a follow-up for 2 years. GDF-15 and other biomarkers were determined on admission in 2079 patients. GDF-15 was moderately elevated (between 1200 and 1800 ng/L) in 770 patients (37.0%), and highly elevated (>1800 ng/L) in 493 patients (23.7%). Elevated levels of GDF-15 independently predicted the risk of the composite end point of death or recurrent myocardial infarction in the conservative group (P=0.016) but not in the invasive group. A significant interaction existed between the GDF-15 level on admission and the effect of treatment strategy on the composite end point. The occurrence of the composite end point was reduced by the invasive strategy at GDF-15 levels >1800 ng/L (hazard ratio, 0.49; 95% confidence interval, 0.33 to 0.73; P=0.001), between 1200 and 1800 ng/L (hazard ratio, 0.68; 95% confidence interval, 0.46 to 1.00; P=0.048), but not <1200 ng/L (hazard ratio, 1.06; 95% confidence interval, 0.68 to 1.65; P=0.81). Patients with ST-segment depression or a troponin T level >0.01 microg/L with a GDF-15 level <1200 ng/L did not benefit from the invasive strategy.

CONCLUSIONS

GDF-15 is a potential tool for risk stratification and therapeutic decision making in patients with non-ST-elevation acute coronary syndrome as initially diagnosed by ECG and troponin levels. A prospective randomized trial is needed to validate these findings.