John Birkhead

Evaluation Of Risk Scores For Risk Stratification Of Acute Coronary Syndromes In The Myocardial Infarction National Audit Project (MINAP) Database

To compare the discriminative performance of the PURSUIT, GUSTO-1, GRACE, SRI and EMMACE risk models, assess their performance among risk supergroups and evaluate the EMMACE risk model over the wider spectrum of acute coronary syndrome (ACS). Design: Observational study of a national registry. Setting: All acute hospitals in England and Wales. Patients: 100 686 cases of ACS between 2003 and 2005. Main outcome measures: Model performance (C-index) in predicting the likelihood of death over the time period for which they were designed. The C-index, or area under the receiver-operating curve, range 0–1, is a measure of the discriminative performance of a model. Results: The C-indexes were: PURSUIT C-index 0.79 (95% confidence interval 0.78 to 0.80); GUSTO-1 0.80 (0.79 to 0.81); GRACE in-hospital 0.80 (0.80 to 0.81); GRACE 6-month 0.80 (0.79 to 0.80); SRI 0.79 (0.78 to 0.80); and EMMACE 0.78 (0.77 to 0.78). EMMACE maintained its ability to discriminate 30-day mortality throughout different ACS diagnoses. Recalibration of the model offered no notable improvement in performance over the original risk equation. For all models the discriminative performance was reduced in patients with diabetes, chronic renal failure or angina. Conclusion: The five ACS risk models maintained their discriminative performance in a large unselected English and Welsh ACS population, but performed less well in higher-risk supergroups. Simpler risk models had comparable performance to more complex risk models. The EMMACE risk score performed well across the wider spectrum of ACS diagnoses.

Improving care for patients with acute coronary syndromes: initial results from the National Audit of Myocardial Infarction Project (MINAP)

Objective: To describe the improvements in care that have followed the introduction of an electronic data entry and analysis system providing contemporary feedback on the management of acute coronary syndromes in 230 hospitals in England and Wales. Design: Observational study Methods: A secure electronic system was used to transfer encrypted data on patients with acute coronary syndromes from collaborating hospitals to central servers for analysis. Immediate online data entry to the central servers by hospitals allowed contemporary analyses of performance and immediate comparison with the national aggregate performance. Results: The records of 156 902 patients receiving a final diagnosis of acute coronary syndrome during three years between October 2000 and September 2003 were analysed. Of 69 113 patients with ST segment elevation infarction, 75.4% received thrombolytic treatment. Between the first and last years of the study the median interval from hospital arrival to treatment fell for eligible patients from 38 (interquartile range 22–58) to 20 (interquartile range 14–28) minutes. By mid 2003 77.6% were receiving thrombolytic treatment within 30 minutes of arrival. The proportion treated within two hours of onset of symptoms increased from 32.5% to 40.3% (a difference of 7.8 percentage points, p < 0.0001). The use of secondary prevention medication for acute coronary syndromes increased over this period: angiotensin converting enzyme inhibitors, 62.4% to 72.4%; β blockers, 76.3% to 82.6%; statins, 69.6% to 83.8%; and aspirin, 89.3% to 90.2%. Conclusion: The provision of contemporary online performance analyses has underpinned substantial improvement in the care of patients with acute coronary syndromes.

Impact of specialty of admitting physician and type of hospital on care and outcome for myocardial infarction in England and Wales during 2004-5: observational study

Abstract Objective To examine process of care and outcome for patients admitted with acute myocardial infarction to hospitals in England and Wales in relation to type of consultant care and type of hospital. Design Observational study of 88 782 patients admitted with myocardial infarction during 2004-5, using records from the national audit of myocardial infarction project (MINAP) database. Outcome measures Use of reperfusion treatment and secondary prevention drugs, use of angiography, and 90 day mortality of patients admitted under the care of cardiologists and non-cardiologists in hospitals with and without facilities for coronary intervention. Findings 36% of patients were admitted under the care of a cardiologist and 20% to a hospital with coronary interventional facilities. Patients admitted under cardiologists had fewer comorbidities than other patients and were more likely to have reperfusion treatment (12 266/14 433 (85%) v 13 682/17 064 (80%)) and appropriate secondary prevention drugs. Overall, 27 431/79 374 (35%) of patients had angiography. Relatively more patients admitted to interventional hospitals (8167/14 661; 56%) than to other hospitals had angiography (19 264/64 713; 30%). The adjusted risk of death by 90 days for patients treated in interventional compared with non-interventional hospitals was 0.93 (95% confidence interval 0.82 to 1.06). The adjusted risk of death at 90 days for patients admitted under cardiologists compared with non-cardiologists was 0.86 (0.81 to 0.91). Conclusions Patients cared for by cardiologists had less comorbidity than other patients. They were more likely to receive proved treatments and angiography, and they had a lower adjusted 90 day mortality. Large differences existed in the use of angiography between interventional and non-interventional hospitals. These findings show wide variations in the management and outcome of patients with myocardial infarction in England and Wales.

Early impact of insulin treatment on mortality for hyperglycaemic patients without known diabetes who present with an acute coronary syndrome.

Objective: To determine the effect of insulin for the management of hyperglycaemia in non-diabetic patients presenting with acute coronary syndrome. Methods: An observational study from the MINAP (National Audit of Myocardial Infarction Project) database during 2003–5 in 201 hospitals in England and Wales. Patients were those with a final diagnosis of troponin-positive acute coronary syndrome who were not previously known to have diabetes mellitus and whose blood glucose on admission was ⩾11 mmol/l. The main outcome measure was death at 7 and 30 days. Results: Of 38 864 patients who were not previously known to be diabetic, 3835 (9.9%) had an admission glucose ⩾11 mmol/l. Of patients having a clear treatment strategy, 36% received diabetic treatment (31% with insulin). Mortality at 7 and 30 days was 11.6% and 15.8%, respectively, for those receiving insulin, and 16.5% and 22.1%, respectively, for those who did not. Compared with those who received insulin, after adjustment for age, gender, co-morbidities and admission blood glucose concentration, patients who were not treated with insulin had a relative increased risk of death of 56% at 7 days and 51% at 30 days (HR 1.56, 95% CI 1.22 to 2.0, p<0.001 at 7 days; HR 1.51, 95% CI 1.22 to 1.86, p<0.001 at 30 days). Conclusion: In non-diabetic patients with acute coronary syndrome and hyperglycaemia, treatment with insulin was associated with a reduction in the relative risk of death, evident within 7 days of admission, which persists at 30 days.

Euro Heart Survey 2009 Snapshot: Regional variations in presentation and management of patients with AMI in 47 countries

Aims: Detailed data on patients admitted for acute myocardial infarction (AMI) on a European-wide basis are lacking. The Euro Heart Survey 2009 Snapshot was designed to assess characteristics, management, and hospital outcomes of AMI patients throughout European Society of Cardiology (ESC) member countries in a contemporary ‘real-world’ setting, using a methodology designed to improve the representativeness of the survey. Methods: Member countries of the ESC were invited to participate in a 1-week survey of all patients admitted for documented AMI in December 2009. Data on baseline characteristics, type of AMI, management, and complications were recorded using a dedicated electronic form. In addition, we used data collected during the same time period in national registries in Sweden, England, and Wales. Data were centralized at the European Heart House. Results: Overall, 4236 patients (mean age 66±13 years; 31% women) were included in the study in 47 countries. Sixty per cent of patients had ST-segment elevation myocardial infarction, with 50% having primary percutaneous coronary intervention and 21% fibrinolysis. Aspirin and thienopyridines were used in >90%. Unfractionated and low-molecular-weight heparins were the most commonly used anticoagulants. Statins, beta-blockers, and angiotensin-converting enzyme inhibitors were used in >80% of the patients. In-hospital mortality was 6.2%. Regional differences were observed, both in terms of population characteristics, management, and outcomes. Conclusions: In-hospital mortality of patients admitted for AMI in Europe is low. Although regional variations exist in their presentation and management, differences are limited and have only moderate impact on early outcomes.

Predictors of in-hospital mortality for patients admitted with ST-elevation myocardial infarction: a real-world study using the Myocardial Infarction National Audit Project (MINAP) database

Objective: Although early thrombolysis reduces the risk of death in STEMI patients, mortality remains high. We evaluated factors predicting inpatient mortality for patients with STEMI in a “real-world” population. Design: Analysis of the Myocardial Infarction National Audit Project (MINAP) database using multivariate logistic regression and area under the receiver operating curve analysis. Setting: All acute hospitals in England and Wales. Patients: 34 722 patients with STEMI from 1 January 2003 to 31 March 2005. Results: Inpatient mortality was 10.6%. The highest odds ratios for inpatient survival were aspirin therapy given acutely and out-of-hospital thrombolysis, independently associated with a mortality risk reduction of over half. A 10-year increase in age doubled inpatient mortality risk, whereas cerebrovascular disease increased it by 1.7. The risk model comprised 14 predictors of mortality, C index  =  0.82 (95% CI 0.82 to 0.83, p<0.001). A simple model comprising age, systolic blood pressure (SBP) and heart rate (HR) offered a C index of 0.80 (0.79 to 0.80, p<0.001). Conclusion: The strongest predictors of in-hospital survival for STEMI were aspirin therapy given acutely and out-of-hospital thrombolysis, Previous STEMI models have focused on age, SBP and HR We have confirmed the importance of these predictors in the discrimination of death after STEMI, but also demonstrated that other potentially modifiable variables impact upon the prediction of short-term mortality.

Determinants and outcomes of coronary angiography after non-ST-segment elevation myocardial infarction. A cohort study of the Myocardial Ischaemia National Audit Project (MINAP)

Objective: To investigate determinants of, and outcomes from, coronary angiography and intervention in patients with non-ST-segment elevation myocardial infarction (NSTEMI). Design: Observational study. Setting: 44 British hospitals with interventional facilities. Patients: 13 489 admissions with NSTEMI; July 2005 to December 2006. Main outcome measures: Rate of angiography during index admission; death and readmission to hospital within 180 days. Results: Significantly lower rates of angiography were seen for women, the elderly, the most deprived and those having cardiac, and most non-cardiac, comorbidities. Performance of angiography, compared with no angiography, was not associated with lower rate of readmission (multiple adjusted hazard ratio (HR) = 0.96, 95% CI 0.74 to 1.24) unless accompanied by coronary intervention (HR = 0.73, 95% CI 0.56 to 0.95). Angiography was associated with reduction in 180-day mortality for survivors of hospitalisation (HR = 0.59, 95% CI 0.49 to 0.72); with greater reduction when followed by an intervention (HR = 0.34, 95% CI 0.28 to 0.42). This mortality benefit after intervention was seen both in women (HR = 0.42, 95% CI 0.29 to 0.60) and men (HR = 0.31, 95% CI 0.24 to 0.41), and across age groups: <65 years (HR = 0.25, 95% CI 0.14 to 0.44), 65–79 years (HR = 0.29, 95% CI 0.22 to 0.39) and ⩾80 years (HR = 0.52, 95% CI 0.37 to 0.74). Mortality benefit was not significantly attenuated by the presence of comorbidities. Conclusion: Performance of angiography and coronary intervention after NSTEMI was associated with mortality benefit that persisted in the presence of both cardiac and non-cardiac comorbidities. Mortality benefit was seen across age groups and was similar for both sexes.

The impact of pre-hospital thrombolytic treatment on re-infarction rates: analysis of the Myocardial Infarction National Audit Project (MINAP).

Objective: To examine the frequency and determinants of re-infarction after thrombolytic treatment of ST-elevation myocardial infarction (STEMI). Design: Observational study of national registry. Setting: Emergency ambulance services and admitting hospitals in England and Wales. Patients: 35 356 patients with STEMI given thrombolytic treatment in 2005–6. Main outcome measures: Re-infarction during hospital admission. Results: For 22 391 patients (63.3%) the presence or absence of re-infarction was recorded, and 1460 (6.5%) had re-infarction. Re-infarction rates with in-hospital treatment were similar for reteplase (6.5%) and tenecteplase (6.4%). When the interval from pre-hospital treatment to hospital arrival was greater than 30 minutes re-infarction rates were 12.5% for reteplase, and 11.4% for tenecteplase. Overall, re-infarction rates were higher after pre-hospital treatment with tenecteplase than reteplase (9.6% vs 6.6%, p = 0.005). After multivariate analysis independent predictors of re-infarction for tenecteplase were pre-hospital treatment, OR 1.44 (95% CI 1.21 to 1.71, p<0.001) and weight in the highest quartile compared to the lowest, OR 1.66 (95% CI 1.19 to 2.31, p = 0.003). For reteplase neither factor predicted re-infarction. Bleeding was less common with pre-hospital treatment—overall 1.8% against 3.1%; intracerebral bleeding 0.4% against 0.7%. Conclusion: Pre-hospital treatment with tenecteplase was associated with higher re-infarction rates. Longer intervals from pre-hospital treatment to arrival in hospital were associated with high re-infarction rates for both tenecteplase and reteplase. Differences in the use of adjunctive anti-thrombotic therapy in the two treatment environments may underlie the differences in re-infarction rates and bleeding complications observed between pre-hospital and in-hospital thrombolytic treatment.

The Pre-Hospital Fibrinolysis Experience in Europe and North America and Implications for Wider Dissemination

OBJECTIVES The primary objective of this report was to describe the infrastructures and processes of selected European and North American pre-hospital fibrinolysis (PHL) programs. A secondary objective is to report the outcome data of the PHL programs surveyed. BACKGROUND Despite its benefit in reducing mortality in patients with ST-segment elevation myocardial infarction, PHL remained underused in North America. Examination of existing programs may provide insights to help address barriers to the implementation of PHL. METHODS The leading investigators of PHL research projects/national registries were invited to respond to a survey on the organization and outcomes of their affiliated PHL programs. RESULTS PHL was successfully deployed in a wide range of geographic territories (Europe: France, Sweden, Vienna, England, and Wales; North America: Houston, Edmonton, and Nova Scotia) and was delivered by healthcare professionals of varying expertise. In-hospital major adverse outcomes were rare with mortality of 3% to 6%, reinfarction of 2% to 5%, and stroke of <2%. CONCLUSIONS Combining formal protocols for PHL for some patients with direct transportation of others to a percutaneous coronary intervention hospital for primary percutaneous coronary intervention would allow for tailored reperfusion therapy for patients with ST-segment elevation myocardial infarction. Insights from a variety of international settings may promote widespread use of PHL and increase timely coronary reperfusion worldwide.

Resuscitated cardiac arrest and prognosis following myocardial infarction

Objectives To determine whether resuscitated cardiac arrest (CA) complicating ST elevation myocardial infarction (STEMI) impacts outcome, particularly in patients surviving to discharge. Background Resuscitated CA complicating STEMI is associated with increased inpatient mortality. The impact on later prognosis is unclear. Methods We analysed data from the UK Myocardial Ischaemia National Audit Project for STEMI patients admitted during January 2008–March 2010. We used survival analyses to assess the independent impact of resuscitated CA during the index episode on inhospital, 30 days, 1 year and medium term all-cause mortality. Results Of 48 749 STEMI patients, 5308 (10.9%) were recorded as having a CA. Of these, 1557 (29.3%) died on the day of CA. In survivors, after covariate adjustment, resuscitated CA was associated with increased risk of death during the index admission (HR 4.05 (3.69 to 4.45) p<0.001). In patients surviving to discharge, a history of resuscitated CA was associated with increased risk of death to 30 days (HR 1.53 (1.18 to 2.00), p<0.001). However, beyond 30 days, resuscitated CA was not associated with increased mortality risk (1-year HR 0.95 (0.79 to 1.14, p=0.596); 3.5 years HR 0.90 (0.78 to 1.04), p=0.144). The influence of resuscitated CA on inhospital or 30-day mortality was similar whether CA occurred before or after hospital admission. Where the resuscitated CA rhythm was asystole, inhospital mortality was higher compared with ventricular arrhythmia (p<0.001) or pulseless electrical activity (p=0.011). Late resuscitated CA (occurring after the day of index STEMI) was associated with higher 30-day postdischarge mortality compared with early resuscitated CA (p=0.023). Conclusions STEMI complicated by resuscitated CA merits careful monitoring in the early period postevent. In contemporary practice, there is no impact of resuscitated CA on longer-term prognosis.