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Archive for the ‘Acute coronary syndrome’ Category

Hospital Choice & Life Expectancy After Myocardial Infarction

Bucholz et al report an analysis of data from the Cooperative Cardiovascular Project (of Medicare beneficiaries hospitalized for myocardial infarction with acute myocardial infarction between 1994 and 1996). The authors classified hospital performance based on quintiles of 30-day mortaility for acute myocardial infarction. Cox proportional hazard models with stratification by case-mix was used to calculate life expectancy (area under survival curve: 17 year follow up). There was a gradient of life expectancy with hospital performance quintile across all case mix. The case mix strata had the expected gradient of life expectancy (healthiest best LE, east healthy worst).

Abstract

BACKGROUND

Thirty-day risk-standardized mortality rates after acute myocardial infarction are
commonly used to evaluate and compare hospital performance. However, it is not
known whether differences among hospitals in the early survival of patients with
acute myocardial infarction are associated with differences in long-term survival.

METHODS

We analyzed data from the Cooperative Cardiovascular Project, a study of Medicare
beneficiaries who were hospitalized for acute myocardial infarction between 1994
and 1996 and who had 17 years of follow-up. We grouped hospitals into five
strata that were based on case-mix severity. Within each case-mix stratum, we
compared life expectancy among patients admitted to high-performing hospitals
with life expectancy among patients admitted to low-performing hospitals. Hospital
performance was defined by quintiles of 30-day risk-standardized mortality
rates. Cox proportional-hazards models were used to calculate life expectancy.

RESULTS

The study sample included 119,735 patients with acute myocardial infarction who
were admitted to 1824 hospitals. Within each case-mix stratum, survival curves of
the patients admitted to hospitals in each risk-standardized mortality rate quintile
separated within the first 30 days and then remained parallel over 17 years of
follow-up. Estimated life expectancy declined as hospital risk-standardized mortality
rate quintile increased. On average, patients treated at high-performing
hospitals lived between 0.74 and 1.14 years longer, depending on hospital case
mix, than patients treated at low-performing hospitals. When 30-day survivors
were examined separately, there was no significant difference in unadjusted or
adjusted life expectancy across hospital risk-standardized mortality rate quintiles.

CONCLUSIONS

In this study, patients admitted to high-performing hospitals after acute myocardial
infarction had longer life expectancies than patients treated in low-performing
hospitals. This survival benefit occurred in the first 30 days and persisted over the
long term.
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GRACE Score in Patients with COAD

Rothnie et al report on the performance of the GRACE score for acute coronary syndromes in patients with concomitant chronic obstructive airways disease (COAD or COPD). The data source was the Myocardial Ischemia National Audit Project (MINAP) registry. The authors found that the GRACE score underestimates the risk of acute coronary syndrome. Alternative models are explored (1.3 x GRACE estimate or MINAP registry derived GRACE). The authors also quantify the reclassification and discuss its implications.

Abstract

Objective

To assess the accuracy of Global Registry of Acute Coronary Events (GRACE) scores in predicting mortality at 6 months for people with chronic obstructive
pulmonary disease (COPD) and to investigate how it might be improved.

Methods

Data were obtained on 481 849 patients with acute coronary syndrome admitted to UK hospitals between January 2003 and June 2013 from the Myocardial Ischaemia National Audit Project (MINAP) database. We compared risk of death between patients with COPD and those without COPD at 6 months,
adjusting for predicted risk of death. We then assessed whether several modifications improved the accuracy of the GRACE score for people with COPD.
Results The risk of death after adjusting for GRACE score predicted that risk of death was higher for patients with COPD than that for other patients (RR 1.29, 95% CI 1.28 to 1.33). Adding smoking into the GRACE score model did not improve accuracy for patients with COPD. Either adding COPD into the model (relative risk (RR) 1.00, 0.94 to 1.02) or multiplying the GRACE score by 1.3
resulted in better performance (RR 0.99, 0.96 to 1.01).

Conclusions

GRACE scores underestimate risk of death for people with COPD. A more accurate prediction of risk of death can be obtained by adding COPD into the GRACE score equation, or by multiplying the GRACE score predicted risk of death by 1.3 for people with COPD. This means that one third of patients with COPD currentlyclassified as low risk should be classified as moderate risk,
and could be considered for more aggressive early treatment after non-ST-segment elevation myocardial infarction or unstable angina.

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Journal Club 21 October 2015

Paper

High-sensitivity cardiac troponin I at presentation in patients with suspected acute coronary syndrome: a cohort study

Presenter

SB

Summary

Summary

Background Suspected acute coronary syndrome is the commonest reason for emergency admission to hospital and is a large burden on health-care resources. Strategies to identify low-risk patients suitable for immediate discharge would have major benefits.

Methods

We did a prospective cohort study of 6304 consecutively enrolled patients with suspected acute coronary syndrome presenting to four secondary and tertiary care hospitals in Scotland. We measured plasma troponin concentrations at presentation using a high-sensitivity cardiac troponin I assay. In derivation and validation cohorts, we evaluated the negative predictive value of a range of troponin concentrations for the primary outcome of index myocardial infarction, or subsequent myocardial infarction or cardiac death at 30 days. This trial is registered with ClinicalTrials.gov (number NCT01852123).

Findings

782 (16%) of 4870 patients in the derivation cohort had index myocardial infarction, with a further 32 (1%) re-presenting with myocardial infarction and 75 (2%) cardiac deaths at 30 days. In patients without myocardial infarction at presentation, troponin concentrations were less than 5 ng/L in 2311 (61%) of 3799 patients, with a negative predictive value of 99·6% (95% CI 99·3–99·8) for the primary outcome. The negative predictive value was consistent across groups stratifi ed by age, sex, risk factors, and previous cardiovascular disease. In two independent
validation cohorts, troponin concentrations were less than 5 ng/L in 594 (56%) of 1061 patients, with an overall negative predictive value of 99·4% (98·8–99·9). At 1 year, these patients had a lower risk of myocardial infarction and cardiac death than did those with a troponin concentration of 5 ng/L or more (0·6% vs 3·3%; adjusted hazard ratio
0·41, 95% CI 0·21–0·80; p<0·0001).

Interpretation

Low plasma troponin concentrations identify two-thirds of patients at very low risk of cardiac events who could be discharged from hospital. Implementation of this approach could substantially reduce hospital admissions and have major benefi ts for both patients and health-care providers.

Supplementary Material

The editorial is available here.

Journal Club 29 April 2015

Paper

Long-Term Use of Ticagrelor in Patients with Prior Myocardial Infarction

Presenter

AL

Summary

BACKGROUND

The potential benefit of dual antiplatelet therapy beyond 1 year after a myocardial infarction has not been established. We investigated the efficacy and safety of ticagrelor, a P2Y12 receptor antagonist with established efficacy after an acute coronary syndrome, in this context.

METHODS

We randomly assigned, in a double-blind 1:1:1 fashion, 21,162 patients who had had a myocardial infarction 1 to 3 years earlier to ticagrelor at a dose of 90 mg twice daily, ticagrelor at a dose of 60 mg twice daily, or placebo. All the patients were to receive low-dose aspirin and were followed for a median of 33 months. The primary efficacy end point was the composite of cardiovascular death, myocardial infarction, or stroke. The primary safety end point was Thrombolysis in Myocardial Infarction (TIMI) major bleeding.

RESULTS

The two ticagrelor doses each reduced, as compared with placebo, the rate of the primary efficacy end point, with Kaplan–Meier rates at 3 years of 7.85% in the group that received 90 mg of ticagrelor twice daily, 7.77% in the group that received 60 mg of ticagrelor twice daily, and 9.04% in the placebo group (hazard ratio for 90 mg of ticagrelor vs. placebo, 0.85; 95% confidence interval [CI], 0.75 to 0.96; P=0.008; hazard ratio for 60 mg of ticagrelor vs. placebo, 0.84; 95% CI, 0.74 to 0.95; P=0.004). Rates of TIMI major bleeding were higher with ticagrelor (2.60% with 90 mg and 2.30% with 60 mg) than with placebo (1.06%) (P<0.001 for each dose vs. placebo); the rates of intracranial hemorrhage or fatal bleeding in the three groups were 0.63%, 0.71%, and 0.60%, respectively.

CONCLUSIONS

In patients with a myocardial infarction more than 1 year previously, treatment with ticagrelor significantly reduced the risk of cardiovascular death, myocardial infarction, or stroke and increased the risk of major bleeding.

Supplementary Material

A useful presentation is available here.

Journal Club 3 September 2014

Paper

Nonsystem Reasons for Delay in Door-to-Balloon Time and Associated In-Hospital Mortality
A Report From the National Cardiovascular Data Registry

Presenter

SH (paper chosen by RS)

Summary

Objectives

The goal of this study was to characterize nonsystem reasons for delay in door-to-balloon time (D2BT) and the
impact on in-hospital mortality.

Background

Studies have evaluated predictors of delay in D2BT, highlighting system-related issues and patient demographic
characteristics. Limited data exist, however, for nonsystem reasons for delay in D2BT.

Methods

We analyzed nonsystem reasons for delay in D2BT among 82,678 ST-segment elevation myocardial infarction
patients who underwent primary percutaneous coronary intervention within 24 h of symptom onset in the Cath-
PCI Registry from January 1, 2009, to June 30, 2011.

Results

Nonsystem delays occurred in 14.7% of patients (n 12,146). Patients with nonsystem delays were more likely to
be older, female, African American, and have greater comorbidities. The in-hospital mortality for patients treated without
delay was 2.5% versus 15.1% for those with delay (p 0.01). Nonsystem delay reasons included delays in providing
consent (4.4%), difficult vascular access (8.4%), difficulty crossing the lesion (18.8%), “other” (31%), and cardiac
arrest/intubation (37.4%). Cardiac arrest/intubation delays had the highest in-hospital mortality (29.9%) despite the
shortest time delay (median D2BT: 84 min; 25th to 75th percentile: 64 to 108 min); delays in providing consent had
a relatively lower in-hospital mortality rate (9.4%) despite the longest time delay (median D2BT: 100 min; 25th to
75th percentile: 80 to 131 min). Mortality for delays due to difficult vascular access, difficulty crossing a lesion, and
other was also higher (8.0%, 5.6%, and 5.9%, respectively) compared with nondelayed patients (p 0.0001). After
adjustment for baseline characteristics, in-hospital mortality remained higher for patients with nonsystem delays.

Conclusions

Nonsystem reasons for delay in D2BT in ST-segment elevation myocardial infarction patients presenting for primary
percutaneous coronary intervention are common and associated with high in-hospital mortality.

Additional Material

This paper was assessed as poor in relation to the inferences related to non-system delays. The editorial by Grines and Schreiber was fully supported. It is available here.

Journal Club 2 October 2013

Paper

Thrombus Aspiration during ST-Segment Elevation Myocardial Infarction

Presenter

YS

Summary

Background

The clinical effect of routine intracoronary thrombus aspiration before primary percutaneous
coronary intervention (PCI) in patients with ST-segment elevation myocardial
infarction (STEMI) is uncertain. We aimed to evaluate whether thrombus
aspiration reduces mortality.

Methods

We conducted a multicenter, prospective, randomized, controlled, open-label clinical
trial, with enrollment of patients from the national comprehensive Swedish
Coronary Angiography and Angioplasty Registry (SCAAR) and end points evaluated
through national registries. A total of 7244 patients with STEMI undergoing PCI were
randomly assigned to manual thrombus aspiration followed by PCI or to PCI only.
The primary end point was all-cause mortality at 30 days.

Results

No patients were lost to follow-up. Death from any cause occurred in 2.8% of the
patients in the thrombus-aspiration group (103 of 3621), as compared with 3.0% in
the PCI-only group (110 of 3623) (hazard ratio, 0.94; 95% confidence interval [CI],
0.72 to 1.22; P = 0.63). The rates of hospitalization for recurrent myocardial infarction
at 30 days were 0.5% and 0.9% in the two groups, respectively (hazard ratio,
0.61; 95% CI, 0.34 to 1.07; P = 0.09), and the rates of stent thrombosis were 0.2%
and 0.5%, respectively (hazard ratio, 0.47; 95% CI, 0.20 to 1.02; P = 0.06). There were
no significant differences between the groups with respect to the rate of stroke or
neurologic complications at the time of discharge (P = 0.87). The results were consistent
across all major prespecified subgroups, including subgroups defined according
to thrombus burden and coronary flow before PCI.

Conclusions

Routine thrombus aspiration before PCI as compared with PCI alone did not reduce
30-day mortality among patients with STEMI.

Journal Club 27 March 2013

Paper

Fibrinolysis or Primary PCI in ST-Segment Elevation Myocardial Infarction

Presenter

LAM

Summary

Background

It is not known whether prehospital fibrinolysis, coupled with timely coronary angiography, provides a clinical outcome similar to that with primary percutaneous
coronary intervention (PCI) early after acute ST-segment elevation myocardial infarction (STEMI).

Methods

Among 1892 patients with STEMI who presented within 3 hours after symptom
onset and who were unable to undergo primary PCI within 1 hour, patients were
randomly assigned to undergo either primary PCI or fibrinolytic therapy with bolus
tenecteplase (amended to half dose in patients ≥75 years of age), clopidogrel, and
enoxaparin before transport to a PCI-capable hospital. Emergency coronary angiography was performed if fibrinolysis failed; otherwise, angiography was performed
6 to 24 hours after randomization. The primary end point was a composite of
death, shock, congestive heart failure, or reinfarction up to 30 days.

Results

The primary end point occurred in 116 of 939 patients (12.4%) in the fibrinolysis
group and in 135 of 943 patients (14.3%) in the primary PCI group (relative risk in the
fibrinolysis group, 0.86; 95% confidence interval, 0.68 to 1.09; P=0.21). Emergency
angiography was required in 36.3% of patients in the fibrinolysis group, whereas the
remainder of patients underwent angiography at a median of 17 hours after randomization. More intracranial hemorrhages occurred in the fibrinolysis group than in the
primary PCI group (1.0% vs. 0.2%, P=0.04; after protocol amendment, 0.5% vs. 0.3%,
P=0.45). The rates of nonintracranial bleeding were similar in the two groups.

Conclusion

Prehospital fibrinolysis with timely coronary angiography resulted in effective reperfusion in patients with early STEMI who could not undergo primary PCI within
1 hour after the first medical contact. However, fibrinolysis was associated with a
slightly increased risk of intracranial bleeding.