Comparison of long-term mortality across the spectrum of acute coronary syndromes

Clinical risk stratification in the emergency department predicts long-term cardiovascular outcomes in a population-based cohort presenting with acute chest pain: primary results of the Olmsted county chest pain study

The long-term cardiovascular outcomes of a population-based cohort presenting to the emergency department (ED) with chest pain and classified with a clinical risk stratification algorithm are not well documented. The Olmsted County Chest Pain Study is a community-based study that included all consecutive patients presenting with chest pain consistent with unstable angina presenting to all EDs in Olmsted County, Minnesota. Patients were classified according to the Agency for Health Care Policy and Research (AHCPR) criteria. Patients with ST elevation myocardial infarction and chest pain of noncardiac origin were excluded. Main outcome measures were major adverse cardiovascular and cerebrovascular events (MACCE) at 30 days and at a median follow-up of 7.3 years, and mortality through a median of 16.6 years.The 2271 patients were classified as follows: 436 (19.2%) as high risk, 1557 (68.6%) as intermediate risk, and 278 (12.2%) as low risk. Thirty-day MACCE occurred in 11.5% in the high-risk group, 6.2% in the intermediate-risk group, and 2.5% in the low-risk group (p < 0.001). At 7.3 years, significantly more MACCE were recorded in the intermediate-risk (hazard ratio [HR], 1.91; 95% confidence intervals [CI], 1.33-2.75) and high-risk groups (HR, 2.45; 95% CI, 1.67-3.58). Intermediate- and high-risk patients demonstrated a 1.38-fold (95% CI, 0.95-2.01; p = 0.09) and a 1.68-fold (95% CI, 1.13-2.50; p = 0.011) higher mortality, respectively, compared to low-risk patients at 16.6 years. At 7.3 and at 16.6 years of follow-up, biomarkers were not incrementally predictive of cardiovascular risk.In conclusion, a widely applicable rapid clinical algorithm using AHCPR criteria can reliably predict long-term mortality and cardiovascular outcomes. This algorithm, when applied in the ED, affords an excellent opportunity to identify patients who might benefit from a more aggressive cardiovascular risk factor management strategy.

Long-term mortality of patients undergoing cardiac catheterization for ST-elevation and non-ST-elevation myocardial infarction

BACKGROUND

There are limited contemporary data comparing long-term outcomes after cardiac catheterization for ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI).

METHODS AND RESULTS

We studied patients undergoing cardiac catheterization for STEMI (n=2413) and NSTEMI (n=1974) between 1999 and 2005 with at least 1 significant coronary lesion > or =75%. We compared adjusted mortality rates over restricted time intervals and the differential impact of early revascularization on mortality stratified by ST-elevation status. Between 1999 and 2007, 1274 patients died, with a median follow-up of 4 years. A piece-wise analysis showed a higher adjusted mortality risk for STEMI during the first 2 months (adjusted hazard ratio, 1.85; 95% confidence interval, 1.45 to 2.38) and a lower adjusted mortality risk for STEMI after 2 months (adjusted hazard ratio, 0.68; 95% confidence interval, 0.59 to 0.83). Compared with late or no revascularization, early revascularization was associated with a lower adjusted risk of mortality for both STEMI (adjusted hazard ratio, 0.73; 95% confidence interval, 0.58 to 0.90) and NSTEMI (adjusted hazard ratio, 0.76; 95% confidence interval, 0.65 to 0.89) (P for interaction=0.22).

CONCLUSIONS

Among a contemporary cohort of acute MI patients with significant coronary disease during cardiac catheterization, STEMI was associated with a higher risk of short-term mortality, but NSTEMI was associated with a higher risk of long-term mortality. Early revascularization was associated with a similar improvement in long-term outcomes for both STEMI and NSTEMI. These data suggest that in clinical investigations of early revascularization among patients with NSTEMI, extended follow-up may be necessary to demonstrate treatment benefit.

Cost effectiveness of fondaparinux in non-ST-elevation acute coronary syndrome

BACKGROUND

Fondaparinux has been shown to reduce the risk of major bleeding and 30-day mortality compared with enoxaparin, in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS). However, its cost effectiveness is not well known.

OBJECTIVE

To evaluate the effectiveness and economic attractiveness of fondaparinux relative to enoxaparin in patients with NSTE-ACS treated with triple antiplatelet therapy and early (non-urgent) invasive strategy.

METHODS

The decision model compares two alternative strategies: subcutaneous (SC) enoxaparin (1 mg/kg 12 hourly) versus SC fondaparinux (2.5 mg/day) in NSTE-ACS patients pre-treated with triple antiplatelet therapy and early revascularization. Cost-effectiveness and cost-utility analyses were performed from a healthcare perspective, based on a Markov model with a time horizon of the patient lifespan. Univariate sensitivity analysis and probabilistic (Monte Carlo) microsimulation analysis were performed.

RESULTS

In the base-case analysis (65 years, Thrombolysis In Myocardial Infarction [TIMI] score 4), the use of fondaparinux was associated with a significant reduction in major bleeding, a slight reduction in adverse cardiac events, and minor improvements in survival and QALYs, together with a small reduction in costs. The dominance of fondaparinux over enoxaparin remained unchanged in the univariate sensitivity analyses. According to Monte Carlo simulation, fondaparinux was cost saving in 99.9% of cases.

CONCLUSION

Compared with enoxaparin, the use of fondaparinux in patients with NSTE-ACS managed with an early invasive strategy appears to be cost effective, even in patients with a low risk of bleeding.

Cardiovascular magnetic resonance of scar and ischemia burden early after acute ST elevation and non-ST elevation myocardial infarction

BACKGROUND

The acute coronary syndrome diagnosis includes different classifications of myocardial infarction, which have been shown to differ in their pathology, as well as their early and late prognosis. These differences may relate to the underlying extent of infarction and/or residual myocardial ischemia. The study aim was to compare scar and ischemia mass between acute non-ST elevation myocardial infarction (NSTEMI), ST-elevation MI with Q-wave formation (Q-STEMI) and ST-elevation MI without Q-wave formation (Non-Q STEMI) in-vivo, using cardiovascular magnetic resonance (CMR).

METHODS AND RESULTS

This was a prospective cohort study of twenty five consecutive patients with NSTEMI, 25 patients with thrombolysed Q-STEMI and 25 patients with thrombolysed Non-Q STEMI. Myocardial function (cine imaging), ischemia (adenosine stress first pass myocardial perfusion) and scar (late gadolinium enhancement) were assessed by CMR 2-6 days after presentation and before any invasive revascularisation procedure. All subjects gave written informed consent and ethical committee approval was obtained. Scar mass was highest in Q-STEMI, followed by Non-Q STEMI and NSTEMI (24.1%, 15.2% and 3.8% of LV mass, respectively; p < 0.0001). Ischemia mass showed the reverse trend and was lowest in Q-STEMI, followed by Non-Q STEMI and NSTEMI (6.9%, 14.7% and 19.9% of LV mass, respectively; p = 0.012). The combined mass of scar and ischemia was similar between the three groups (p = 0.17). The ratio of scar to ischemia was 3.5, 1.0 and 0.2 for Q-STEMI, Non-Q STEMI and NSTEMI, respectively.

CONCLUSION

Prior to revascularisation, the ratio of scar to ischemia differs between NSTEMI, Non-Q STEMI and Q-STEMI, whilst the combined scar and ischemia mass is similar between these three types of MI. These results provide in-vivo confirmation of the diverse pathophysiology of different types of acute myocardial infarction and may explain their divergent early and late prognosis.

Using triple antiplatelet therapy in patients with non-ST elevation acute coronary syndrome managed invasively: a cost-effectiveness analysis

OBJECTIVES

To assess the incremental cost-effectiveness ratio (ICER) of glycoprotein IIb/IIIa (GPIIb/IIIa) inhibitors in patients with non-ST elevation acute coronary syndrome (NSTE-ACS) pretreated with aspirin and clopidogrel undergoing an early invasive treatment strategy.

METHODS

Cost-effectiveness analysis and cost-utility analysis were performed from a health-care system perspective, based on a Markov model with a time horizon of the patient life span. The risk of death and ischemic events was assessed using the Thrombolysis in Myocardial Infarction (TIMI) risk score. We compared three strategies: 1) routine upstream use of a GPIIb/IIIa inhibitor to all patients before angiography, 2) deferred selective use of abciximab in the catheterization laboratory just before angioplasty, and 3) double antiplatelet therapy without GPIIb/IIIa inhibitors. Both univariate sensitivity analysis and second-order probabilistic microsimulation were performed.

RESULTS

In the base case (65 years old, TIMI score 3), strategy A was the most effective, with an ICER of 15,150 euros per quality-adjusted life-year gained. Strategy B was dominated by a combination of strategies A and C. The ICER was very sensitive to the age and baseline risk of the patient. According to the widely accepted cost-effectiveness thresholds, strategy A would be cost-effective only in patients with an intermediate to high TIMI score, especially within the younger age groups. The probability that strategy A was cost-effective under the base case was 91.2%.

CONCLUSIONS

The use of GPIIb/IIIa inhibitors upstream in high-risk NSTE-ACS patients (TIMI score > or = 3) pretreated with aspirin and clopidogrel is cost-effective, particularly in the younger age groups.

2007 Guideline update for unstable angina/non-ST-segment elevation myocardial infarction: focus on antiplatelet and anticoagulant therapies

OBJECTIVE

To summarize key changes in the 2007 American College of Cardiology/American Heart Association (ACC/AHA) guideline recommendations for pharmacologic therapy as they relate to antiplatelets and anticoagulants, and to evaluate the evidence from several landmark trials that was used to support the guideline updates for these agents.

DATA SOURCES

Literature was accessed through MEDLINE (1950-January 2008) using the search terms acute coronary syndromes, unstable angina (UA), non-ST-segment elevation myocardial infarction (NSTEMI), antiplatelet, and anticoagulant. All papers were cross-referenced to identify additional studies.

STUDY SELECTION AND DATA EXTRACTION

ACC/AHA guidelines, relevant original research articles, and review articles were evaluated. Studies with more than 1000 patients were the focus of the review.

DATA SYNTHESIS

UA and NSTEMI are the most common presentations of acute coronary syndrome. The recently updated ACC/AHA guidelines for management of this condition were based on significant advances in pharmacotherapy including expanded use of drug-eluting stents, pretreatment with clopidogrel, and newer anticoagulants such as bivalirudin and fondaparinux. Landmark trials have been published that describe advances in the use of antiplatelets and anticoagulants. According to the guidelines, unfractionated heparin (UFH) and enoxaparin are preferred options for both invasive and conservative management. Enoxaparin was noninferior to UFH for invasive management in the SYNERGY trial, although it was associated with a higher incidence of bleeding. Other alternatives for an invasive strategy per the guidelines include bivalirudin and fondaparinux. Bivalirudin (alone or with glycoprotein [GP] IIb/IIIa inhibitor) was compared with heparin plus GP IIb/IIIa inhibitor in the ACUITY trial of patients undergoing early invasive management. The bivalirudin groups were noninferior to standard of care, although bivalirudin alone was associated with less bleeding. Fondaparinux was found to be noninferior to enoxaparin and was associated with fewer bleeding events in the OASIS-5 study of patients who were not treated with an early invasive approach. Accordingly, the guidelines 1list fondaparinux as an alternative for a conservative strategy or in patients at increased risk of bleeding.

CONCLUSIONS

Clinicians should be familiar with the updated 2007 ACC/AHA guidelines and the clinical trial evidence that serves as the basis for these recommendations. It is paramount for institutions to outline a preferred and consistent treatment approach. These decisions should involve a review of established efficacy, bleeding risk, need for anticoagulant reversal, costs, and clinician familiarity with different treatment regimens.

Protective mechanisms of resveratrol against ischemia-reperfusion-induced damage in hearts obtained from Zucker obese rats: the role of GLUT-4 and endothelin

The resveratrol-induced cardiac protection was studied in Zucker obese rats. Rats were divided into five groups: group 1, lean control; group 2, obese control (OC); group 3, obese rats treated orally with 5 mg kg(-1) day(-1) of resveratrol (OR) for 2 wk; group 4, obese rats received 10% glucose solution ad libitum for 3 wk (OG); and group 5, obese rats received 10% glucose for 3 wk and resveratrol (OGR) during the 2nd and 3rd wk. Body weight, serum glucose, and insulin were measured, and then hearts were isolated and subjected to 30 min of ischemia followed by 120 min of reperfusion. Heart rate, coronary flow, aortic flow, developed pressure, the incidence of reperfusion-induced ventricular fibrillation, and infarct size were measured. Resveratrol reduced body weight and serum glucose in the OR compared with the OC values (414 +/- 10 g and 7.08 +/- 0.41 mmol/l, respectively, to 378 +/- 12 g and 6.11 +/- 0.44 mmol/l), but insulin levels were unchanged. The same results were obtained for the OG vs. OGR group. Resveratrol improved postischemic cardiac function in the presence or absence of glucose intake compared with the resveratrol-free group. The incidence of ventricular fibrillation and infarct size was reduced by 83 and 20% in the OR group, and 67 and 16% in the OGR group, compared with the OC and OG groups, respectively. Resveratrol increased GLUT-4 expression and reduced endothelin expression and cardiac apoptosis in ischemic-reperfused hearts in the presence or absence of glucose intake. Thus the protective effect of resveratrol could be related to its direct effects on the heart.

Long-term survival after out-of-hospital cardiac arrest

OBJECTIVE

The purpose of this study was to assess the long-term survival after OHCA.

METHODS

All OHCA-calls where the Copenhagen Mobile Emergency Care Unit (MECU) was involved from 1994 to1998 are included in this study. Data were collected prospectively. Data on long-term survival was obtained from the Danish Causes of Death Registry and the Danish Civil Registration System. We conducted a search to find out whether patients were still alive on 31 January 2005.

RESULTS

Resuscitation was indicated and attempted in 1095 cases and 95 patients (8.7%) survived to discharge. Of these 75% had an initial rhythm of VF, 13% had asystole, 10% had PEA and 2% were unknown. Survival was 87% after one year and survival after 10 years was 46% with a significantly lower survival for patients over 60 years.

CONCLUSION

Long-term survival after out-of-hospital cardiac arrest in a physician-staffed emergency system was comparable to survival after myocardial infarction with 46% being alive after ten years.

Impact of diagnosis and sex on long-term prognosis in acute coronary syndromes

BACKGROUND

There is limited information on long-term outcome in patients surviving the acute phase of an acute coronary syndrome (ACS). As yet, the effects of the type of syndrome and sex on mortality and morbidity in the long run have not been well described.

METHODS

We studied 1618 patients <80 years old with ACS and alive 30 days after hospitalization in a coronary care unit. The patients were followed for 5 years. They were divided into 4 groups according to the type of ACS (ST-segment elevation myocardial infarction [STEMI], non-STEMI, unstable angina pectoris high risk, and unstable angina pectoris low risk).

RESULTS

There was no significant sex difference in unadjusted 5-year mortality (P = .20). After adjustment for age, the hazard ratio with the corresponding 95% CI for a higher late 5-year mortality in women in relation to men was 0.89 (0.70-1.13, P = .34). Women were hospitalized for heart failure significantly more frequently during follow-up, a significance that disappeared after adjustment for age. Non-STEMI was associated with a significantly higher long-term mortality than STEMI, before but not after adjustment for covariates (hazard ratio [95% CI] 1.02 [0.75-1.37], P = .92). Of these, age, ST depression on admission, and early revascularization with percutaneous coronary intervention appeared to be of particular importance. Non-STEMI had a significantly higher rate of acute/subacute revascularization during follow-up, even after adjustment for age.

CONCLUSIONS

Before, but not after, adjustment for covariates, a diagnosis of non-STEMI was associated with a poorer prognosis than other types of ACS. Small sex differences in long-term outcome in survivors of ACS were found.

Risk assessment after acute coronary syndrome

Lots of potential but will it end up being yet another risk score?