A comparison of the national registry of myocardial infarction 2 with the cooperative cardiovascular project

Comparison of demographic profile, risk factors, and in-hospital outcome in young and old patients with acute coronary syndrome: A single-center experience

Background:

Coronary artery disease (CAD) is witnessing a demographic transition with increasing prevalence in younger individuals. Data is scarce comparing various characteristics of acute coronary syndrome (ACS) between young and old patients in an Indian setting. Hence, we evaluated the epidemiological, demographic, risk factor, and outcome profile of young and old ACS patients in Indian setting.

Methods:

This was a prospective observational study, which enrolled 50 consecutive ACS patients each into two groups: younger (≤45 years) and elderly (>45 years), respectively. Comparison of clinical presentation, electrocardiography, echocardiographic findings, conventional, nonconventional risk factors, and in-hospital outcomes including duration of hospital stay and major adverse cardiac events (MACE) were made between the two groups. Multivariate regression analysis of risk factors as determinants of MACE adjusting for other confounding factors was also performed.

Results:

Fifty patients in each group were compared. Mean age in the younger and elderly group was 36 ± 4.69 and 61.58 ± 10.69 years, respectively. Male sex, smoking, family history of CAD, hyperhomocysteinemia, and obesity were observed more in the younger population. While dyslipidemia, low physical activity, diabetes mellitus, and history of previous ACS was more in the older population. Single-vessel disease was more common in younger patients while multivessel involvement was more common in elderly patients. Older patients had longer hospital stays and more in-hospital MACE including deaths. By multivariate analysis, shock was found to be an independent predictor of MACE in both groups.

Conclusion:

Younger ACS patients have a different risk profile and better in-hospital outcomes compared to older patients.

Atherosclerotic risk factors and their association with hospital mortality among patients with first myocardial infarction (from the National Registry of Myocardial Infarction)

Few studies have examined associations between atherosclerotic risk factors and short-term mortality after first myocardial infarction (MI). Histories of 5 traditional atherosclerotic risk factors at presentation (diabetes, hypertension, smoking, dyslipidemia, and family history of premature heart disease) and hospital mortality were examined among 542,008 patients with first MIs in the National Registry of Myocardial Infarction (1994 to 2006). On initial MI presentation, history of hypertension (52.3%) was most common, followed by smoking (31.3%). The least common risk factor was diabetes (22.4%). Crude mortality was highest in patients with MI with diabetes (11.9%) and hypertension (9.8%) and lowest in those with smoking histories (5.4%) and dyslipidemia (4.6%). The inclusion of 5 atherosclerotic risk factors in a stepwise multivariate model contributed little toward predicting hospital mortality over age alone (C-statistic = 0.73 and 0.71, respectively). After extensive multivariate adjustments for clinical and sociodemographic factors, patients with MI with diabetes had higher odds of dying (odds ratio [OR] 1.23, 95% confidence interval [CI] 1.20 to 1.26) than those without diabetes and similarly for hypertension (OR 1.08, 95% CI 1.06 to 1.11). Conversely, family history (OR 0.71, 95% CI 0.69 to 0.73), dyslipidemia (OR 0.62, 95% CI 0.60 to 0.64), and smoking (OR 0.85, 95% CI 0.83 to 0.88) were associated with decreased mortality (C-statistic = 0.82 for the full model). In conclusion, in the setting of acute MI, histories of diabetes and hypertension are associated with higher hospital mortality, but the inclusion of atherosclerotic risk factors in models of hospital mortality does not improve predictive ability beyond other major clinical and sociodemographic characteristics.

Diabetes Mellitus and Trends in Hospital Survival After Myocardial Infarction, 1994 to 2006

Background—

Patients with diabetes mellitus (DM) are at high risk for mortality after myocardial infarction (MI). Despite an overall trend of reduced mortality after MI, the mortality gap between MI patients with and without DM did not decrease over time in previous analyses. We assessed recent trends in hospital mortality for patients with MI according to DM status.

Methods and Results—

We analyzed data from the National Registry of Myocardial Infarction, a contemporary registry of MI patients treated in 1964 hospitals, representing approximately one fourth of all US acute care hospitals. The study comprised 1734431 MI patients enrolled from 1994 to 2006, including 502315 (29%) with DM. Crude hospital mortality decreased in all patients between 1994 and 2006 but remained higher in patients with DM compared with those without DM throughout the study. The absolute difference in mortality between patients with and without DM significantly narrowed over time, from 15.6% versus 11.5% in 1994 to 8.0% versus 6.8% in 2006 ( P <0.001 for DM × time interaction). The adjusted odds ratio for mortality associated with DM declined from 1.24 (95% confidence interval, 1.16–1.32) in 1994 to 1.08 (95% confidence interval, 0.99–1.19) in 2006 ( P <0.001 for trend). The largest improvement in hospital mortality was observed in diabetic women (17.9% in 1994 versus 8.4% in 2006; P <0.001).

Conclusions—

The hospital mortality gap between MI patients with and without DM narrowed significantly from 1994 to 2006, with the greatest improvement observed in women with DM.

Differences in symptom presentation and hospital mortality according to type of acute myocardial infarction

BACKGROUND

Chest pain/discomfort (CP) is the hallmark symptom of acute myocardial infarction (MI), but some patients with MI present without CP. We hypothesized that MI type (ST-segment elevation MI [STEMI] or non-STEMI [NSTEMI]) may be associated with the presence or absence of CP.

METHODS

We investigated the association between CP at presentation and MI type, hospital care, and mortality among 1,143,513 patients with MI in the National Registry of Myocardial Infarction (NRMI) from 1994 to 2006.

RESULTS

Overall, 43.6% of patients with NSTEMI and 27.1% of patients with STEMI presented without CP. For both MI type, patients without CP were older, were more frequently female, had more diabetes or history of heart failure, were more likely to delay hospital arrival, and were less likely to receive evidence-based medical therapies and invasive cardiac procedures. Multivariable analysis indicated that NSTEMI (vs STEMI) was the strongest predictor of atypical symptoms (adjusted odds ratio [95% CI], 1.93 [1.91-1.95]). Within the 4 CP/MI type categories, hospital mortality was highest for no CP/STEMI (27.8%), followed by no CP/NSTEMI (15.3%) and CP/STEMI (9.6%), and was lowest for CP/NSTEMI (5.4%). The adjusted odds ratio of mortality was 1.38 (1.35-1.41) for no CP (vs CP) in the STEMI group and 1.31 (1.28-1.34) in the NSTEMI group.

CONCLUSIONS

Hospitalized patients with NSTEMI were nearly 2-fold more likely to present without CP than patients with STEMI. Patients with MI without CP were less quickly diagnosed and treated and had higher adjusted odds of hospital mortality, regardless of whether they had ST-segment elevation.

Association of age and sex with myocardial infarction symptom presentation and in-hospital mortality

CONTEXT

Women are generally older than men at hospitalization for myocardial infarction (MI) and also present less frequently with chest pain/discomfort. However, few studies have taken age into account when examining sex differences in clinical presentation and mortality.

OBJECTIVE

To examine the relationship between sex and symptom presentation and between sex, symptom presentation, and hospital mortality, before and after accounting for age in patients hospitalized with MI.

DESIGN, SETTING, AND PATIENTS

Observational study from the National Registry of Myocardial Infarction, 1994-2006, of 1,143,513 registry patients (481,581 women and 661,932 men).

MAIN OUTCOME MEASURES

We examined predictors of MI presentation without chest pain and the relationship between age, sex, and hospital mortality.

RESULTS

The proportion of MI patients who presented without chest pain was significantly higher for women than men (42.0% [95% CI, 41.8%-42.1%] vs 30.7% [95% CI, 30.6%-30.8%]; P < .001). There was a significant interaction between age and sex with chest pain at presentation, with a larger sex difference in younger than older patients, which became attenuated with advancing age. Multivariable adjusted age-specific odds ratios (ORs) for lack of chest pain for women (referent, men) were younger than 45 years, 1.30 (95% CI, 1.23-1.36); 45 to 54 years, 1.26 (95% CI, 1.22-1.30); 55 to 64 years, 1.24 (95% CI, 1.21-1.27); 65 to 74 years, 1.13 (95% CI, 1.11-1.15); and 75 years or older, 1.03 (95% CI, 1.02-1.04). Two-way interaction (sex and age) on MI presentation without chest pain was significant (P < .001). The in-hospital mortality rate was 14.6% for women and 10.3% for men. Younger women presenting without chest pain had greater hospital mortality than younger men without chest pain, and these sex differences decreased or even reversed with advancing age, with adjusted OR for age younger than 45 years, 1.18 (95% CI, 1.00-1.39); 45 to 54 years, 1.13 (95% CI, 1.02-1.26); 55 to 64 years, 1.02 (95% CI, 0.96-1.09); 65 to 74 years, 0.91 (95% CI, 0.88-0.95); and 75 years or older, 0.81 (95% CI, 0.79-0.83). The 3-way interaction (sex, age, and chest pain) on mortality was significant (P < .001).

CONCLUSION

In this registry of patients hospitalized with MI, women were more likely than men to present without chest pain and had higher mortality than men within the same age group, but sex differences in clinical presentation without chest pain and in mortality were attenuated with increasing age.

Number of coronary heart disease risk factors and mortality in patients with first myocardial infarction

CONTEXT

Few studies have examined the association between the number of coronary heart disease risk factors and outcomes of acute myocardial infarction in community practice.

OBJECTIVE

To determine the association between the number of coronary heart disease risk factors in patients with first myocardial infarction and hospital mortality.

DESIGN

Observational study from the National Registry of Myocardial Infarction, 1994-2006.

PATIENTS

We examined the presence and absence of 5 major traditional coronary heart disease risk factors (hypertension, smoking, dyslipidemia, diabetes, and family history of coronary heart disease) and hospital mortality among 542,008 patients with first myocardial infarction and without prior cardiovascular disease.

MAIN OUTCOME MEASURE

All-cause in-hospital mortality.

RESULTS

A majority (85.6%) of patients who presented with initial myocardial infarction had at least 1 of the 5 coronary heart disease risk factors, and 14.4% had none of the 5 risk factors. Age varied inversely with the number of coronary heart disease risk factors, from a mean age of 71.5 years with 0 risk factors to 56.7 years with 5 risk factors (P for trend < .001). The total number of in-hospital deaths for all causes was 50,788. Unadjusted in-hospital mortality rates were 14.9%, 10.9%, 7.9%, 5.3%, 4.2%, and 3.6% for patients with 0, 1, 2, 3, 4, and 5 risk factors, respectively. After adjusting for age and other clinical factors, there was an inverse association between the number of coronary heart disease risk factors and hospital mortality adjusted odds ratio (1.54; 95% CI, 1.23-1.94) among individuals with 0 vs 5 risk factors. This association was consistent among several age strata and important patient subgroups.

CONCLUSION

Among patients with incident acute myocardial infarction without prior cardiovascular disease, in-hospital mortality was inversely related to the number of coronary heart disease risk factors.

Benefit of transferring ST-segment-elevation myocardial infarction patients for percutaneous coronary intervention compared with administration of onsite fibrinolytic declines as delays increase

BACKGROUND

Although randomized trials suggest that transfer for primary percutaneous coronary intervention (X-PCI) in ST-segment-elevation myocardial infarction is superior to onsite fibrinolytic therapy (O-FT), the generalizability of these findings to routine clinical practice is unclear because door-to-balloon (XDB) times are rapid in randomized trials but are frequently prolonged in practice. We hypothesized that delays resulting from transfer would reduce the survival advantage of X-PCI compared with O-FT.

METHODS AND RESULTS

ST-segment-elevation myocardial infarction patients enrolled in the National Registry of Myocardial Infarction (NRMI) within 12 hours of pain onset were identified. Propensity matching of patients treated with X-PCI and O-FT was performed, and the effect of PCI-related delay on in-hospital mortality was assessed. PCI-related delay was calculated by subtracting the XDB from the door-to-needle time in each matched pair. Conditional logistic regression adjusted for patient and hospital variables identified the XDB door-to-needle time at which no mortality advantage for X-PCI over O-FT was present. Eighty-one percent of X-PCI patients were matched (n=9506) to O-FT patients (n=9506). In the matched cohort, X-PCI was performed with delays >90 minutes in 68%. Multivariable analysis found no mortality advantage for X-PCI over O-FT when XDB door-to-needle time exceeded ≈120 minutes.

CONCLUSION

PCI-related delays are extensive among patients transferred for X-PCI and are associated with poorer outcomes. No differential excess in mortality was seen with X-PCI compared with O-FT even with long PCI-related delays, but as XDB door-to-needle time times increase, the mortality advantage for X-PCI over O-FT declines.

Association of initial thrombolysis in myocardial infarction flow grade with mortality among patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: a National Registry of Myocardial Infarction-5 (NRMI-5) analysis

BACKGROUND

Initial epicardial coronary flow, as assessed by the Thrombolysis in Myocardial Infarction flow grade (TFG), prior to primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI) has been associated with short- and long-term mortality in randomized clinical trials. This study was designed to determine the relationship between initial TFG and mortality in a large, heterogeneous, real-world population of STEMI patients undergoing pPCI.

METHODS

The relationship between pre-pPCI TFG among patients undergoing pPCI and in-hospital mortality was evaluated among STEMI patients from 2004 to 2006 in the National Registry of Myocardial Infarction.

RESULTS

Of 8,337 STEMI patients, 6,595 (79.1%) had pre-pPCI TFG 0/1, 1,126 (13.5%) had pre-pPCI TFG 2, and 616 (7.4%) had pre-pPCI TFG 3. TFG 0/1 prior to pPCI was associated with 3.4% in-hospital mortality, whereas TFG 2 (2.0%) and TFG 3 (1.8%) were associated with significantly lower mortality (TFG 0/1 vs TFG 2, P = .013; TFG 0/1 vs TFG 3, P = .035). TFG 0/1 prior to pPCI was also associated with a significant increase in the composite of death, recurrent myocardial infarction, heart failure, and shock (16.1%) when compared with patients presenting with TFG 2 (11.5%; P < .001) and TFG 3 (7.6%; P < .001). The difference in this composite was also significant between patients presenting with TFG 2 and TFG 3 (P = .01).

CONCLUSIONS

In a large, heterogeneous group of real-world patients presenting with STEMI, pre-pPCI TFG 0/1 is associated with higher in-hospital mortality and other major adverse cardiovascular events. These results corroborate prior to post hoc analyses from randomized clinical trials and support continued efforts aimed at safely establishing early infarct-related artery patency among patients with STEMI.

Use of intensive lipid-lowering therapy in patients hospitalized with acute coronary syndrome: An analysis of 65,396 hospitalizations from 344 hospita participating in Get With The Guidelines (GWTG)

OBJECTIVES

The study aimed to analyze the use of intensive lipid-lowering therapy (I-LLT) at discharge in a broad population of patients hospitalized with acute coronary syndrome (ACS).

BACKGROUND

Early and intensive statin therapy in ACS has been shown to reduce cardiovascular morbidity and mortality. Utilization and predictors of I-LLT among hospitalized ACS patients are not known.

METHODS

The GWTG database was analyzed for ACS-related hospitalizations from 2005 to 2009. The use of I-LLT (defined as dose of statin or combination therapy likely to produce > 50% reductions in low-density lipoprotein [LDL]) and less intensive lipid-lowering therapy (LI-LLT) at discharge was assessed. Baseline characteristics and temporal trends in LLT were compared in these 2 treatment groups.

RESULTS

Of 65,396 patients receiving LLT, only 25,036 (38.3%) were treated with an I-LLT regimen. Mean total cholesterol, LDL, and triglycerides were significantly higher in the I-LLT group. Even among those with LDL > 130 mg/dL, 50% or less received I-LLT. Predictors of I-LLT at discharge included LLT before admission, hyperlipidemia, prior coronary artery disease, increasing body mass index, and in-hospital percutaneous coronary intervention. Although there was some temporal improvement in the rate of I-LLT from 2005 to 2007, a decline in use of I-LLT was noted in 2008 and 2009. This was attributed to a sharp reduction in use of ezetimibe in combination with statin, without corresponding increases in intensive statin monotherapy.

CONCLUSIONS

In a large cohort of patients admitted with ACS, most of the eligible patients were not discharged on I-LLT. These data suggest the need for better implementation of guideline-recommended intensive statin therapy in patients with ACS.

Use of intensive lipid-lowering therapy in patients hospitalized with acute coronary syndrome: an analysis of 65,396 hospitalizations from 344 hospitals participating in Get With The Guidelines (GWTG)

OBJECTIVES

The study aimed to analyze the use of intensive lipid-lowering therapy (LLT) at discharge in a broad population of patients hospitalized with acute coronary syndrome (ACS).

BACKGROUND

Early and intensive statin therapy in ACS was shown to reduce cardiovascular morbidity and mortality. Utilization and predictors of LLT among hospitalized ACS patients are not known.

METHODS

The GWTG database was analyzed for ACS-related hospitalizations from 2005 to 2009. The use of LLT (defined as dose of statin or combination therapy likely to produce>50% reductions in low-density lipoprotein [LDL]) and less intensive LLT at discharge was assessed. Baseline characteristics and temporal trends in LLT were compared in these 2 treatment groups.

RESULTS

Of 65,396 patients receiving LLT, only 25,036 (38.3%) were treated with an LLT regimen. Mean total cholesterol, LDL, and triglycerides were significantly higher in the LLT group. Even among those with LDL>130 mg/dL, 50% or less received LLT. Predictors of LLT at discharge included LLT before admission, hyperlipidemia, prior coronary artery disease, increasing body mass index, and in-hospital percutaneous coronary intervention. Although there was some temporal improvement in the rate of LLT from 2005 to 2007, a decline in use of LLT was noted in 2008 and 2009. This was attributed to a sharp reduction in use of ezetimibe in combination with statin, without corresponding increases in intensive statin monotherapy.

CONCLUSIONS

In a large cohort of patients admitted with ACS, most of the eligible patients were not discharged on LLT. These data suggest the need for better implementation of guideline-recommended intensive statin therapy in patients with ACS.

[Acute myocardial infarction in young smokers treated by coronary angioplasty. In-hospital prognosis and long-term outcome in a consecutive series of 93 patients]

AIMS OF THE STUDY

The study evaluated in-hospital and long-term outcome of patients less than 50 years old with myocardial infarction within 12 hours after symptom onset treated by coronary angioplasty.

PATIENTS AND METHOD

This is a retrospective study with survival analysis by Kaplan-Meier method in patients included from December 2003 to February 2008.

RESULTS

We included 93 patients aged 42,8+/-5,2 years old with smoking estimated at 27,7+/-12,7 pack-years. Thirty-one patients (33,3%) were dyslipidemic and 36 patients had family history of coronary artery disease. Thirty patients (32,3%) had an anterior myocardial infarction and four patients (4.4%) had Killip greater than 2. Coronary angioplasty was performed within 4.5+/-3.0 hours after symptom onset with TIMI 3 final flow in the culprit vessel in 96.8%. One patient died from cardiogenic shock. With a follow-up of 85 patients during 20.0+/-15.6 months, the survival without death was 98.2% and survival without major cardiac complication was 87.9% at 24 months. Seventy-two patients (85.7%) were taking a betablocker, 81 patients (96.4%) aspirin, 75 patients (89.3%) a statin and 64 patients (76.2%) an angiotensin-converting inhibitor. Only 50 patients (58.8%) were nonsmokers.

CONCLUSION

Thus, young smokers with acute MI treated by coronary angioplasty have a good prognosis during in-hospital stay and long-term outcome. Secondary medical treatment prevention is well followed but there is a low rate of smoking cessation.

Sex differences in mortality after acute myocardial infarction: changes from 1994 to 2006

BACKGROUND

Previous studies have shown that women younger than 55 years have higher hospital mortality rates after acute myocardial infarction (MI) than age-matched men. We examined whether such mortality differences have decreased in recent years.

METHODS

We investigated temporal trends in the hospital case-fatality rates of MI by sex and age from June 1, 1994, through December 31, 2006. The study population included 916,380 patients from the National Registry of Myocardial Infarction with a confirmed diagnosis of MI.

RESULTS

In-hospital mortality decreased markedly between 1994 and 2006 in all patients but more so in women than men. The mortality reduction in 2006 relative to 1994 was largest in women younger than 55 years (52.9%) and lowest in men younger than 55 years (33.3%). In patients younger than 55 years, the absolute decrease in mortality was 3 times larger in women than men (2.7% vs 0.9%). As a result, the excess mortality in younger women (<55 years) compared with men was less pronounced in 2004-2006 (unadjusted odds ratio, 1.32; 95% confidence interval, 1.07-1.67) than it was in 1994-1995 (unadjusted odds ratio, 1.93; 95% confidence interval, 1.67-2.24). The sex difference in mortality decrease was lower in older patients (P = .004 for the interaction among sex, age, and year). Changes in comorbidity and clinical severity features at admission accounted for more than 90% of these mortality trends.

CONCLUSIONS

In recent years, women, particularly younger ones, experienced larger improvements in hospital mortality after MI than men. The narrowing of the mortality gap between younger women and men is largely attributable to temporal changes in risk profiles.

The joint contribution of sex, age and type of myocardial infarction on hospital mortality following acute myocardial infarction

OBJECTIVE

Younger, but not older, women have a higher mortality than men of similar age after a myocardial infarction (MI). We sought to determine whether this relationship is true for both ST elevation MI (STEMI) and non-ST elevation MI (NSTEMI).

DESIGN

Retrospective cohort study.

SETTING

1057 USA hospitals participant in the National Registry of Myocardial Infarction between 2000 and 2006.

PATIENTS

126 172 STEMI and 235 257 NSTEMI patients.

MAIN OUTCOME MEASURE

Hospital death.

RESULTS

For both STEMI and NSTEMI, the younger the patient's age, the greater the excess mortality risk for women compared with men, while older women fared similarly (STEMI) or better (NSTEMI) than men (p<0.0001 for the age-sex interaction). In STEMI, the unadjusted women-to-men RR was 1.68 (95% CI 1.41 to 2.01), 1.78 (1.59 to 1.99), 1.45 (1.34 to 1.57), 1.08 (1.02 to 1.14) and 1.03 (0.98 to 1.07) for age <50 years, age 50-59, age 60-69, age 70-79 and age 80-89, respectively. For NSTEMI, corresponding unadjusted RRs were 1.56 (1.31 to 1.85), 1.42 (1.27 to 1.58), 1.17 (1.09 to 1.25), 0.92 (0.88 to 0.96) and 0.86 (0.83 to 0.89). After adjusting for risk status, the excess risk for younger women compared with men decreased to approximately 15-20%, while a better survival of older NSTEMI women compared with men persisted.

CONCLUSIONS

Sex-related differences in short-term mortality are age-dependent in both STEMI and NSTEMI patients.

Declining in-hospital mortality and increasing heart failure incidence in elderly patients with first myocardial infarction

OBJECTIVES

The purpose of this study was to examine the long-term incidence of heart failure (HF) in elderly patients with myocardial infarction (MI).

BACKGROUND

In-hospital HF is common after MI and is associated with poor short-term prognosis. Limited data exist concerning the long-term incidence or prognosis of HF after MI, particularly in the era of coronary revascularization.

METHODS

A population-based cohort of 7,733 patients > or = 65 years of age hospitalized for a first MI (International Classification of Diseases-9th Revision-Clinical Modification code 410.x) and without a prior history of HF was established between 1994 and 2000 in Alberta, Canada, and followed up for 5 years.

RESULTS

During the index MI hospitalization, 2,831 (37%) MI patients were diagnosed with new HF and 1,024 (13%) died. Among hospital survivors who did not have HF during their index hospitalization (n = 4,291), an additional 3,040 patients (71%) developed HF by 5 years, 64% of which occurred in the first year. In total, 5,871 (76%) elderly patients who survived their first MI developed HF over 5 years. Among those who survived the index hospitalization, the 5-year mortality rate was 39.1% for those with HF during the index MI hospitalization compared with 26.7% among those without HF (p < 0.0001) during the index MI hospitalization. Over the study period, the 5-year mortality rate after MI decreased by 28%, whereas the 5-year rate of HF increased by 25%.

CONCLUSIONS

In this large cohort of elderly patients without a history of HF, HF developed in three-quarters in the 5 years after their first MI; this proportion increased over time as peri-MI mortality rates declined. New-onset HF significantly increases the mortality risk among these patients.

Trends in the use of lipid-lowering medications at discharge in patients with acute myocardial infarction: 1998 to 2006

BACKGROUND

Compelling evidence demonstrates that certain lipid-lowering medications improve outcomes after acute myocardial infarction (AMI), but to what extent national utilization has increased in response to trials and guidelines has not been well studied. The objective of this study is to determine trends in the use of lipid-lowering medications at discharge for AMI.

METHODS

A time trend analysis was conducted on treatment rates with lipid-lowering medications from 1998 to 2006 in 996,364 patients with AMI hospitalized in 1,669 hospitals participating in the National Registry of Myocardial Infarction (NRMI) 3, 4, and 5.

RESULTS

Between 1998 and 2006, use of lipid-lowering medications at discharge increased from 29.3% to 83.8%, (relative risk [RR] 2.86, 95% CI 2.84-2.89, P < .0001). Increased use was observed in men (RR 2.71) and women (RR 3.17); age younger than 65 years (RR 2.32) and 65 years or older (RR 3.46); teaching (RR 2.47) and nonteaching hospitals (RR 2.96); and in all regions of the country. After adjusting for multiple other independent predictors, the temporal increase in use of lipid-lowering medications remained highly significant (RR 2.70, 95% CI 2.68-2.73, P < .0001). A significant upward jump in the rate of lipid-lowering medication use was observed most notably in month 72, corresponding to the publication on the PROVE-IT trial (Pravastatin or Atorvastatin Evaluation and Infection Therapy trial).

CONCLUSIONS

Use of lipid-lowering medications in patients hospitalized with AMI has increased substantially in the United States in the past 8 years. The increase in the lipid-lowering medication use was possibly accelerated by certain randomized clinical trial evidence demonstrating improved outcomes in this high-risk population.

Trends in quality of care for patients with acute myocardial infarction in the National Registry of Myocardial Infarction from 1990 to 2006

BACKGROUND

Trends in the use of guideline-based treatment for acute myocardial infarction (AMI) as well as its association with patient outcomes have not been summarized in a large, longitudinal study. Furthermore, it is unknown whether gender-, race-, and age-based care disparities have narrowed over time.

METHODS AND RESULTS

Using the National Registry of Myocardial Infarction database, we analyzed 2,515,106 patients with AMI admitted to 2,157 US hospitals between July 1990 and December 2006 to examine trends overall and in select subgroups of guideline-based admission, procedural, and discharge therapy use. The contribution of temporal improvements in acute care therapies to declines in in-hospital mortality was examined using logistic regression analysis. From 1990 to 2006, the use of all acute guideline-recommended therapies administered rose significantly for patients with ST-segment elevation myocardial infarction and patients with non-ST-segment myocardial infarction but remained below 90% for most therapies. Cardiac catheterization and percutaneous coronary intervention use increased in patients with ST-segment elevation myocardial infarction and patients with non-ST-segment myocardial infarction, whereas coronary bypass surgery use declined in both groups. Despite overall care improvements, women, blacks, and patients > or =75 years old were significantly less likely to receive revascularization or discharge lipid-lowering therapy relative to their counterparts. Temporal improvements in acute therapies may account for up to 37% of the annual decline in risk for in-hospital AMI mortality.

CONCLUSION

Adherence to American Heart Association/American College of Cardiology practice guidelines has improved care of patients with AMI and is associated with significant reductions in in-hospital mortality rates. However, persistent gaps in overall care as well as care disparities remain and suggest the need for ongoing quality improvement efforts.

Trends in presenting characteristics and hospital mortality among patients with ST elevation and non-ST elevation myocardial infarction in the National Registry of Myocardial Infarction from 1990 to 2006

BACKGROUND

Although ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (AMI) have been the focus of intense clinical investigation, limited information exists on characteristics and hospital mortality of patients not enrolled in clinical trials. Previous large databases have reported declining mortality of patients with STEMI but have not noted substantial mortality change among those with NSTEMI.

METHODS

The National Registry of Myocardial Infarction enrolled 2,515,106 patients at 2,157 US hospitals from 1990 to 2006. Of these, we evaluated 1,950,561 with diagnoses reflecting acute myocardial ischemia on admission.

RESULTS

From 1990 to 2006, the proportion of NSTEMI increased from 14.2% to 59.1% (P < .0001), whereas the proportion of STEMI decreased. Mean age increased (from 64.1 to 66.4 years, P < .0001) as did the proportion of females (from 32.4% to 37.0%, P < .0001). Patients were less likely to report prior angina, prior AMI, or family history of coronary artery disease but more likely to report history of diabetes, hypertension, current smoking, heart failure, prior revascularization, stroke, and hyperlipidemia. From 1994 to 2006, hospital mortality fell among all patients (10.4% to 6.3%), STEMI (11.5% to 8.0%), and NSTEMI (7.1% to 5.2%), (all P < .0001). After adjustment for baseline covariates, hospital mortality fell among all patients by 23.6% (odds ratio [OR] 0.764, 95% CI 0.744-0.785), STEMI by 24.2% (OR 0.758, 0.732-0.784), and NSTEMI by 22.6% (OR 0.774, 0.741-0.809), all P < .001.

CONCLUSIONS

This large, observational database from 1990 to 2006 shows increasing prevalence of NSTEMI and, despite higher risk profile on presentation, falling risk-adjusted hospital mortality in patients with either STEMI or NSTEMI.

The future impact of population growth and aging on coronary heart disease in China: projections from the Coronary Heart Disease Policy Model-China

Background

China will experience an overall growth and aging of its adult population in coming decades. We used a computer model to forecast the future impact of these demographic changes on coronary heart disease (CHD) in China.

Methods

The CHD Policy Model is a validated state-transition, computer simulation of CHD on a national scale. China-specific CHD risk factor, incidence, case-fatality, and prevalence data were incorporated, and a CHD prediction model was generated from a Chinese cohort study and calibrated to age-specific Chinese mortality rates. Disability-adjusted life years (DALYs) due to CHD were calculated using standard methods. The projected population of China aged 35–84 years was entered, and CHD events, deaths, and DALYs were simulated over 2000–2029. CHD risk factors other than age and case-fatality were held at year 2000 levels. Sensitivity analyses tested uncertainty regarding CHD mortality coding, the proportion of total deaths attributable to CHD, and case-fatality.

Results

We predicted 7.8 million excess CHD events (a 69% increase) and 3.4 million excess CHD deaths (a 64% increase) in the decade 2020–2029 compared with 2000–2009. For 2030, we predicted 71% of almost one million annual CHD deaths will occur in persons ≥65 years old, while 67% of the growing annual burden of CHD death and disability will weigh on adults <65 years old. Substituting alternate CHD mortality assumptions led to 17–20% more predicted CHD deaths over 2000–2029, though the pattern of increases in CHD events and deaths over time remained.

Conclusion

We forecast that absolute numbers of CHD events and deaths will increase dramatically in China over 2010–2029, due to a growing and aging population alone. Recent data suggest CHD risk factor levels are increasing, so our projections may underestimate the extent of the potential CHD epidemic in China.

Thrombin receptor and ventricular arrhythmias after acute myocardial infarction

The mechanism mediating the development of ventricular arrhythmia (VA) after acute myocardial infarction (AMI) is still uncertain. Thrombin receptor (TR) activation has been proven to be arrhythmogenic in many other situations, and we hypothesize that it may participate in the genesis of post-AMI VA. Using a left coronary artery ligation rat model of AMI, we found that a local injection of hirudin into the left ventricle (LV) significantly reduced the ratio of VA durations to infarction sizing, whereas injection of thrombin receptor-activating peptide (TRAP) increased the ratios of VA duration to infarction sizing. The effects of TR activation on whole-cell currents were investigated in isolated myocytes. TRAP increased a glibenclamide-sensitive outward current. Pretreatment of rats with glibenclamide (4 mg/kg intraperitoneally) eliminated the effects of a local injection of TRAP on the ratios of VA durations to infarction sizing. TR mRNA and protein expression in the ischemic left ventricle had reached its peak by 20 min postligation in the rat AMI model (P < 0.05). TR-immunoreactive myocytes were observed in infarcted LV but were seldom seen in the right ventricle or in the normal heart. By 60 min, TR transcript levels had returned to control levels. We conclude that increased TR activation and expression in the infarcted LV after AMI may contribute to VA through a mechanism involving glibenclamide-sensitive potassium channels.

Factors associated with longer time from symptom onset to hospital presentation for patients with ST-elevation myocardial infarction

BACKGROUND

Previous studies have demonstrated the effects of single factors, such as age, sex, and race, with longer delays from symptom onset to hospital presentation in patients with ST-elevation myocardial infarction.

METHODS

We studied risk factors individually and in combination to determine the cumulative effect on delay times in 482,327 patients with ST-elevation myocardial infarction enrolled in the National Registry of Myocardial Infarction between January 1, 1995, and December 31, 2004. We analyzed patient subgroups with the following risk factors in combination: younger than 70 years vs 70 years and older, race/ethnicity, men vs women, and nondiabetic vs diabetic.

RESULTS

The geometric mean for delay time was 114 minutes, with a decreasing trend from 123 minutes in 1995 to 113 minutes in 2004 (P < .001). Nearly half of the patients (45.5%) presented more than 2 hours and 8.7% presented more than 12 hours after the onset of symptoms. Compared with the reference group (those < 70 years, men, white, and did not have diabetes mellitus [DM]), subgroups with longer delay times (P < .01 for all) included those younger than 70 years, men, black, and had DM (+43 minutes); those younger than 70 years, women, black, and had DM (+55 minutes); those 70 years and older, men, black, and had DM (+60 minutes); and those 70 years and older, women, black, and had DM (+63 minutes).

CONCLUSIONS

Patient subgroups with a combination of factors (older age, women, Hispanic or black race, and DM) have particularly long delay times that may be 60 minutes longer than subgroups without those characteristics. Improving patient responsiveness in these subgroups represents an important opportunity to improve quality of care and minimize disparities in care.

Delay in presentation and reperfusion therapy in ST-elevation myocardial infarction

BACKGROUND

We studied the relationship between longer delays from symptom onset to hospital presentation and the use of any reperfusion therapy, door-to-balloon time, and door-to-drug time.

METHODS

Cohort study of patients with ST-elevation myocardial infarction enrolled in the National Registry of Myocardial Infarction from January 1, 1995 to December 31, 2004. Delay in hospital presentation was categorized into 1-hour intervals as < or =1 hour, >1-2 hours, >2-3 hours, etc, up to >11-12 hours. The study analyzed 3 groups: 440,398 patients for the association between delay and use of any reperfusion therapy; 67,207 patients for the association between delay and door-to-balloon time; 183,441 patients for the association between delay and door-to-drug time.

RESULTS

In adjusted analyses, patients with longer delays between symptom onset and hospital presentation were less likely to receive any reperfusion therapy, had longer door-to-balloon times, and had longer door-to-needle times (all P <.0001 for linear trend). For patients presenting < or =1 hour, >1-2 hours, >2-3 hours, >9-10 hours, >10-11 hours, and >11-12 hours after symptom onset, the use of any reperfusion therapy were 77%, 77%, 73%, 53%, 50%, and 46%, respectively. Door-to-balloon times were 99, 101, 106, 123, 125, and 123 minutes, respectively, and door-to-drug times were 33, 34, 36, 46, 44, and 47 minutes, respectively.

CONCLUSIONS

Longer delays from symptom onset to hospital presentation were associated with reduced likelihood of receiving primary reperfusion therapy, and even among those treated, late presenters had significantly longer door-to-balloon and door-to-drug times.

Impact of delay in door-to-needle time on mortality in patients with ST-segment elevation myocardial infarction

Fibrinolytic therapy is the most common reperfusion strategy for patients with ST-segment elevation myocardial infarction (STEMI), particularly in smaller centers. Previous studies evaluated the relation between time to treatment and outcomes when few patients were treated within 30 minutes of hospital arrival and many did not receive modern adjunctive medications. To quantify the impact of a delay in door-to-needle time on mortality in a recent and representative cohort of patients with STEMI, a cohort of 62,470 patients with STEMI treated using fibrinolytic therapy at 973 hospitals that participated in the National Registry of Myocardial Infarction from 1999 to 2002 was analyzed. Hierarchical models were used to evaluate the independent effect of door-to-needle time on in-hospital mortality. In-hospital mortality was lower with shorter door-to-needle times (2.9% for < or =30 minutes, 4.1% for 31 to 45 minutes, and 6.2% for >45 minutes; p <0.001 for trend). Compared with those experiencing door-to-needle times < or =30 minutes, adjusted odd ratios (ORs) of dying were 1.17 (95% confidence interval [CI] 1.04 to 1.31) and 1.37 (95% CI 1.23 to 1.52; p for trend <0.001) for patients with door-to-needle times of 31 to 45 and >45 minutes, respectively. This relation was particularly pronounced in those presenting within 1 hour of symptom onset to presentation time (OR 1.25, 95% CI 1.01 to 1.54; OR 1.54, 95% CI 1.27 to 1.87, respectively; p for trend <0.001). In conclusion, timely administration of fibrinolytic therapy continues to significantly impact on mortality in the modern era, particularly in patients presenting early after symptom onset.

Acute reperfusion therapy in ST-elevation myocardial infarction from 1994-2003

BACKGROUND

Appropriate utilization of acute reperfusion therapy is not a national performance measure for ST-elevation myocardial infarction at this time, and the extent of its contemporary use among ideal patients is unknown.

METHODS

From the National Registry of Myocardial Infarction, we identified 238,291 patients enrolled from June 1994 to May 2003 who were ideally suited for acute reperfusion therapy with fibrinolytic therapy or primary percutaneous coronary intervention. We determined rates of not receiving therapy across 3 time periods (June 1994-May 1997, June 1997-May 2000, June 2000-May 2003) and evaluated factors associated with underutilization.

RESULTS

The proportion of ideal patients not receiving acute reperfusion therapy decreased by one half throughout the past decade (time period 1: 20.6%; time period 2: 11.4%; time period 3: 11.6%; P <.001). Utilization remained significantly lower in key subgroups in the most recent time period: those without chest pain (odds ratio [OR] 0.29; 95% confidence interval [CI], 0.27-0.32); those presenting 6 to 12 hours after symptom onset (OR 0.57; 95% CI, 0.52-0.61); those 75 years or older (OR 0.63 compared with patients <55 years old; 95% CI, 0.58-0.68); women (OR 0.88; 95% CI, 0.84-0.93); and non-whites (OR 0.90; 95% CI, 0.83-0.97).

CONCLUSIONS

Utilization of acute reperfusion therapy in ideal patients has improved over the last decade, but more than 10% remain untreated. Measuring and improving its use in this cohort represents an important opportunity to improve care.

Epidemiology of heart failure and left ventricular dysfunction after acute myocardial infarction

The development of heart failure and/or left ventricular systolic dysfunction has long been regarded as an ominous complication, significantly increasing the morbidity and short- and long-term mortality of survivors of acute myocardial infarction. Although the incidence of heart failure after myocardial infarction has fallen over the last few decades, it remains common, complicating up to 45% of infarcts. Moreover, up to 60% of myocardial infarcts will result in left ventricular systolic dysfunction, depending on the exact definition used. Those at greatest risk of developing heart failure are the elderly, females, and those with prior myocardial infarction. Advances in the management of acute myocardial infarction have led to reduced in-hospital mortality (even when complicated by heart failure), but longer-term mortality remains high in these patients.

Hospital Delays in Reperfusion for ST-Elevation Myocardial Infarction

Background— It has been suggested that the survival benefit associated with primary percutaneous coronary intervention (PPCI) in ST-segment elevation myocardial infarction may be attenuated if door-to-balloon (DB) time is delayed by >1 hour beyond door-to-needle (DN) times for fibrinolytic therapy. Whereas DB times are rapid in randomized trials, they are often prolonged in routine practice. We hypothesized that in clinical practice, longer DB-DN times would be associated with higher mortality rates and reduced PPCI survival advantage. We also hypothesized that in addition to PPCI delays, patient risk factors would significantly modulate the relative survival advantage of PPCI over fibrinolysis.

Methods and Results— DB-DN times were calculated by subtracting median DN time from median DB time at a hospital using data from 192 509 patients at 645 National Registry of Myocardial Infarction hospitals. Hierarchical models that adjusted simultaneously for both patient-level risk factors and hospital-level covariates were used to evaluate the relationship between PCI-related delay, patient risk factors, and in-hospital mortality. Longer DB-DN times were associated with increased mortality ( P <0.0001). The DB-DN time at which mortality rates with PPCI were no better than that of fibrinolysis varied considerably depending on patient age, symptom duration, and infarct location.

Conclusions— As DB-DN times increase, the mortality advantage of PPCI over fibrinolysis declines, and this advantage varies considerably depending on patient characteristics. As indicated in the American College of Cardiology/American Heart Association guidelines, both the hospital-based PPCI-related delay (DB-DN time) and patient characteristics should be considered when a reperfusion strategy is selected.

Effectiveness and safety of glycoprotein IIb/IIIa inhibitors and clopidogrel alone and in combination in non-ST-segment elevation myocardial infarction (from the National Registry of Myocardial Infarction-4)

We investigated whether a combination of clopidogrel and glycoprotein (GP) IIb/IIIa inhibitors safely decreases hospital mortality, reinfarction, and major bleeding beyond either therapy alone in patients with non-ST-elevation myocardial infarction (NSTEMI). GP IIb/IIIa inhibitors and clopidogrel, separately, have been shown to decrease adverse outcomes in patients with non-ST-elevation acute coronary syndromes, but the need for combination therapy is uncertain. Multivariate and propensity analyses compared the frequency of death, reinfarction, and major bleeding during hospitalization in 38,691 patients with NSTEMI who were enrolled in the National Registry of Myocardial Infarction 4 from July 2000 to December 2003. Of these, 65% received GP IIb/IIIa inhibitors only, 16.1% clopidogrel only, and 18.8% combination therapy. Among patients who did not undergo percutaneous coronary intervention (PCI), the composite end point of death, reinfarction, and major bleeding was significantly lower with combination therapy than with GP IIb/IIIa inhibitors alone (odds ratio 0.77, 95% confidence interval 0.67 to 0.88). In contrast, this composite end point was significantly higher when combination therapy was employed rather than clopidogrel alone (odds ratio 1.55, 95% confidence interval 1.33 to 1.81). However, among patients who underwent PCI, the composite end point was similar between combination therapy and GP IIb/IIIa inhibitor-only groups (odds ratio 1.01, 95% confidence interval 0.89 to 1.14). Further, there was a strong trend toward a higher composite end point among patients who received combination therapy rather than clopidogrel alone (odds ratio 1.31, 95% confidence interval 0.99 to 1.72). In conclusion, commonly employed strategies using a GP IIb/IIIa inhibitor alone or with the combination of clopidogrel plus GP IIb/IIIa inhibitor in NSTEMI may not be justified in comparison with a simpler strategy of clopidogrel used alone, especially in patients who have not undergone PCI.

Epidemiology of heart failure and left ventricular systolic dysfunction after acute myocardial infarction: prevalence, clinical characteristics, and prognostic importance

The development of heart failure and/or left ventricular systolic dysfunction (LVSD) in the setting of acute myocardial infarction (AMI) results in significant risk far above that of AMI independently. In patients admitted to the hospital for AMI, concomitant heart failure and/or LVSD on hospital admission or development of either or both of these conditions during admission are among the strongest predictors of inhospital death and are associated with significant increases in inhospital, 30-day, and long-term mortality and rehospitalization rates. Given the high risks in this population, aggressive treatment, comprising early initiation and sustained use of evidence-based treatments, is essential for improving prognosis.

Effect of door-to-balloon time on mortality in patients with ST-segment elevation myocardial infarction

OBJECTIVES

We sought to determine the effect of door-to-balloon time on mortality for patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).

BACKGROUND

Studies have found conflicting results regarding this relationship.

METHODS

We conducted a cohort study of 29,222 STEMI patients treated with PCI within 6 h of presentation at 395 hospitals that participated in the National Registry of Myocardial Infarction (NRMI)-3 and -4 from 1999 to 2002. We used hierarchical models to evaluate the effect of door-to-balloon time on in-hospital mortality adjusted for patient characteristics in the entire cohort and in different subgroups of patients based on symptom onset-to-door time and baseline risk status.

RESULTS

Longer door-to-balloon time was associated with increased in-hospital mortality (mortality rate of 3.0%, 4.2%, 5.7%, and 7.4% for door-to-balloon times of < or =90 min, 91 to 120 min, 121 to 150 min, and >150 min, respectively; p for trend <0.01). Adjusted for patient characteristics, patients with door-to-balloon time >90 min had increased mortality (odds ratio 1.42; 95% confidence interval [CI] 1.24 to 1.62) compared with those who had door-to-balloon time < or =90 min. In subgroup analyses, increasing mortality with increasing door-to-balloon time was seen regardless of symptom onset-to-door time (< or =1 h, >1 to 2 h, >2 h) and regardless of the presence or absence of high-risk factors.

CONCLUSIONS

Time to primary PCI is strongly associated with mortality risk and is important regardless of time from symptom onset to presentation and regardless of baseline risk of mortality. Efforts to shorten door-to-balloon time should apply to all patients.

The pre-hospital electrocardiogram and time to reperfusion in patients with acute myocardial infarction, 2000-2002: findings from the National Registry of Myocardial Infarction-4

OBJECTIVES

The aim of this study was to determine the use of pre-hospital electrocardiogram (ECG) in patients with ST-segment elevation myocardial infarction (STEMI) undergoing reperfusion therapy, and evaluate the effect of pre-hospital ECG on door-to-reperfusion times.

BACKGROUND

Although national guidelines recommend the use of pre-hospital ECG, there is limited contemporary information about its current use and effectiveness.

METHODS

Using data from the National Registry of Myocardial Infarction-4, we studied patients with STEMI or left bundle branch block who received acute reperfusion with either fibrinolytic therapy (n = 35,370) or primary percutaneous coronary intervention (PCI) (n = 21,277) within 6 h of admission. We determined the prevalence of pre-hospital ECG use, evaluated the association between pre-hospital ECG and door-to-reperfusion time, and estimated the incremental reduction in time to reperfusion using hierarchical models to adjust for differences in patient and hospital characteristics.

RESULTS

A pre-hospital ECG was performed in 4.5% of the fibrinolytic therapy cohort and in 8.0% of the PCI cohort. After adjusting for patient and hospital characteristics, the use of pre-hospital ECG was associated with a significantly shorter geometric mean door-to-drug time: 24.6 min (95% confidence interval [CI]: 23.7 to 25.5) vs. 34.7 min (95% CI: 34.2 to 35.3; p < 0.0001), and a significantly shorter geometric mean door-to-balloon time (94.0 min [95% CI: 91.8 to 96.3] vs. 110.3 min [95% CI: 108.7 to 112.0]; p < 0.0001).

CONCLUSIONS

The national use of pre-hospital ECG to diagnose and facilitate the treatment of STEMI remains low. When used, however, pre-hospital ECG is associated with a significantly shorter time to reperfusion.

Relation Between Hospital Specialization With Primary Percutaneous Coronary Intervention and Clinical Outcomes in ST-Segment Elevation Myocardial Infarction

Background— Hospitals with primary percutaneous coronary intervention (PPCI) capability may choose to predominately offer PPCI to their patients with ST-segment elevation myocardial infarction (STEMI), or they may selectively offer PPCI or fibrinolytic therapy based on patient and hospital-level factors. Whether a greater level of hospital specialization with PPCI is associated with better quality of care is unknown.

Methods and Results— We analyzed data from the National Registry of Myocardial Infarction-4 to compare in-hospital mortality and times to treatment in STEMI across different levels of hospital specialization with PPCI. We divided 463 hospitals into quartiles of PPCI specialization based on the relative proportion of reperfusion-treated patients who underwent PPCI (≤34.0%, >34.0 to 62.5%, >62.5 to 88.5%, >88.5%). Hierarchical multivariable regression assessed whether PPCI specialization was associated with better outcomes, after adjusting for patient and hospital characteristics, including PPCI volume. We found that greater PPCI specialization was associated with a lower relative risk of in-hospital mortality in patients treated with PPCI (adjusted relative risk comparing the highest and lowest quartiles, 0.64; P =0.006) but not in those treated with fibrinolytic therapy. Compared with patients at hospitals in the lowest quartile of PPCI specialization, adjusted door-to-balloon times in the highest quartile were significantly shorter (99.6 versus 118.3 minutes; P <0.001), and the likelihood of door-to-balloon times exceeding 90 minutes was significantly lower (relative risk, 0.78; P <0.001). Adjusting for PPCI specialization diminished the association between PPCI volume and clinical outcomes.

Conclusions— Greater specialization with PPCI is associated with lower in-hospital mortality and shorter door-to-balloon times in STEMI patients treated with PPCI.

Hospital improvement in time to reperfusion in patients with acute myocardial infarction, 1999 to 2002

OBJECTIVES

The purpose of this study was to analyze recent trends in door-to-reperfusion time and to identify hospital characteristics associated with improved performance.

BACKGROUND

Rapid reperfusion improves survival for patients with acute ST-segment elevation myocardial infarction (STEMI).

METHODS

In this retrospective observational study from the National Registry of Myocardial Infarction (NRMI)-3 and -4, between 1999 and 2002, we analyzed door-to-needle and door-to-balloon times in patients admitted with STEMI and receiving fibrinolytic therapy (n = 68,439 patients in 1,015 hospitals) or percutaneous coronary intervention (n = 33,647 patients in 421 hospitals) within 6 h of hospital arrival.

RESULTS

In 1999, only 46% of the patients in the fibrinolytic therapy cohort were treated within the recommended 30-min door-to-needle time; only 35% of the patients in the percutaneous coronary intervention cohort were treated within the recommended 90-min door-to-balloon time. Improvement in these times to reperfusion over the four-year study period was not statistically significant (door-to-needle: -0.01 min/year, 95% confidence interval [CI] -0.24 to +0.23, p > 0.9; door-to-balloon: -0.57 min/year, 95% CI -1.24 to +0.10, p = 0.09). Only 33% (337 of 1,015) of hospitals improved door-to-needle time by more than one min/year, and 26% (110 of 421) improved door-to-balloon time by more than three min/year. No hospital characteristic was significantly associated with improvement in door-to-needle time. Only high annual percutaneous coronary intervention volume and location in New England were significantly associated with greater improvement in door-to-balloon time.

CONCLUSIONS

Fewer than one-half of patients with STEMI receive reperfusion in the recommended door-to-needle or door-to-balloon time, and mean time to reperfusion has not decreased significantly in recent years. Relatively few hospitals have shown substantial improvement.

Effect of statin use within the first 24 hours of admission for acute myocardial infarction on early morbidity and mortality

We determined the effects of early statin treatment in acute myocardial infarction (AMI) on in-hospital morbidity and mortality. Experimental models of ischemia and reperfusion have shown that statins have early cardioprotective effects. However, the effect of statin use within the first 24 hours of admission on early morbidity and mortality in AMI has not been well studied. Data were collected on 300,823 patients who had AMI in the National Registry of Myocardial Infarction 4. In-hospital events were compared between patients who continued statin therapy received before the index AMI hospitalization (n = 17,118) or newly started statin therapy within the first 24 hours of hospitalization (n = 21,978) and patients who did not receive early statin treatment (n = 126,128) or whose statin therapy was discontinued (n = 9,411). New or continued treatment with a statin in the first 24 hours was associated with a decreased risk of mortality compared with no statin use (4.0% and 5.3% compared with 15.4% no statin). Discontinuation of statin treatment was associated with a slightly increased risk of mortality (16.5%). Early statin use was also associated with a lower incidence of cardiogenic shock, arrhythmias, cardiac arrest, rupture, but not recurrent myocardial infarction. Propensity analysis yielded mortality odds ratios of 0.46 for continued therapy, 0.42 for newly started therapy, and 1.25 for discontinued therapy for matched pairs versus no statin therapy (all p values <0.0001). In conclusion, the use of statin therapy within the first 24 hours of hospitalization for AMI is associated with a significantly lower rate of early complications and in-hospital mortality.

Sex and racial differences in the management of acute myocardial infarction, 1994 through 2002

BACKGROUND

Although increased attention has been paid to sex and racial differences in the management of myocardial infarction, it is unknown whether these differences have narrowed over time.

METHODS

With the use of data from the National Registry of Myocardial Infarction, we examined sex and racial differences in the treatment of patients who were deemed to be "ideal candidates" for particular treatments and in deaths among 598,911 patients hospitalized with myocardial infarction between 1994 and 2002.

RESULTS

In the unadjusted analysis, sex and racial differences were observed for rates of reperfusion therapy (for white men, white women, black men, and black women: 86.5, 83.3, 80.4, and 77.8 percent, respectively; P<0.001), use of aspirin (84.4, 78.7, 83.7, and 78.4 percent, respectively; P<0.001), use of beta-blockers (66.6, 62.9, 67.8, and 64.5 percent; P<0.001), and coronary angiography (69.1, 55.9, 64.0, and 55.0 percent; P<0.001). After multivariable adjustment, racial and sex differences persisted for rates of reperfusion therapy (risk ratio for white women, black men, and black women: 0.97, 0.91, and 0.89, respectively, as compared with white men) and coronary angiography (relative risk, 0.91, 0.82, and 0.76) but were attenuated for the use of aspirin (risk ratio, 0.97, 0.98, and 0.94) and beta-blockers (risk ratio, 0.98, 1.00, and 0.96); all risks were unchanged over time. Adjusted in-hospital mortality was similar among white women (risk ratio, 1.05; 95 percent confidence interval, 1.03 to 1.07) and black men (risk ratio, 0.95; 95 percent confidence interval, 0.89 to 1.00), as compared with white men, but was higher among black women (risk ratio, 1.11; 95 percent confidence interval, 1.06 to 1.16) and was unchanged over time.

CONCLUSIONS

Rates of reperfusion therapy, coronary angiography, and in-hospital death after myocardial infarction, but not the use of aspirin and beta-blockers, vary according to race and sex, with no evidence that the differences have narrowed in recent years.

AIH versus prontuário médico no estudo do risco de óbito hospitalar no infarto agudo do miocárdio no Município do Rio de Janeiro, Brasil

O objetivo deste estudo é avaliar o desempenho do Sistema de Informações Hospitalares (SIH) em relação ao prontuário médico na análise dos fatores associados à variação do risco de óbito hospitalar no infarto agudo do miocárdio. O estudo envolveu uma amostra aleatória, estratificada por hospital, de 391 prontuários médicos sorteados com base nos 1.936 formulários de Autorização de Internação Hospitalar (AIH) registrados com o diagnóstico principal de infarto agudo do miocárdio no Município do Rio de Janeiro, Brasil, em 1997. Para estudo dos fatores associados à variação do risco de óbito hospitalar foram usados modelos logísticos a partir do SIH e do prontuário, com construção de curvas ROC para comparar desempenho relativo entre eles. O diagnóstico foi confirmado em 91,7% dos casos; a letalidade foi 20,6%. O modelo desenvolvido a partir do prontuário apresentou o melhor ajuste por incluir variáveis de gravidade e processo não disponíveis no SIH (concordância = 90,1%). O modelo derivado do SIH teve um menor poder explicativo (concordância = 70,6%), mas a correção de erros de digitação e informação através do prontuário não modificou significativamente seu desempenho. A maior limitação do SIH foi o elevado sub-registro do diagnóstico secundário.

Older Emergency Department Patients With Acute Myocardial Infarction Receive Lower Quality of Care Than Younger Patients

STUDY OBJECTIVE

We assessed the independent relationship between age and the quality of medical care provided to patients presenting to the emergency department (ED) with acute myocardial infarction.

METHODS

We conducted a 2-year retrospective cohort study of 2,216 acute myocardial infarction patients presenting urgently to 5 EDs in Colorado and California from July 1, 2000, through June 30, 2002. Data on patient characteristics, clinical presentation, and ED processes of care were obtained from the ED record and ECG review. Patients were divided into 6 groups based on their age at the time of their ED visit: younger than 50 years, 50 to 59 years, 60 to 69 years, 70 to 79 years, 80 to 89 years, and 90 years or older. Hierarchic multivariable regression was used to assess the independent association between age and the provision of aspirin, beta-blockers, and reperfusion therapy (fibrinolytic agent or percutaneous coronary intervention) in the ED to eligible acute myocardial infarction patients.

RESULTS

Of ideal candidates for treatment in the ED, 1,639 (80.5%) of 2,036 received aspirin, 552 (60.3%) of 916 received beta-blockers, and 358 (77.8%) of 460 received acute reperfusion therapy. After adjustment for demographic, medical history, and clinical factors, older patients were less likely to receive aspirin (odds ratio [OR] 0.85, 95% confidence interval [CI] 0.77 to 0.93), beta-blockers (OR 0.79, 95% CI 0.71 to 0.88), and reperfusion therapy (OR 0.30, 95% CI 0.18 to 0.52).

CONCLUSION

Older patients presenting to the ED with acute myocardial infarction receive lower-quality medical care than younger patients. Further investigation to identify the reasons for this disparity and to intervene to reduce gaps in care quality will likely lead to improved outcomes for older acute myocardial infarction patients.

ST-segment depression on the initial electrocardiogram in acute myocardial infarction-prognostic significance and its effect on short-term mortality: A report from the National Registry of Myocardial Infarction (NRMI-2, 3, 4)

This study analyzed 255,256 patients who had acute myocardial infarction and were enrolled in the National Registry of Myocardial Infarction 2, 3, and 4 (1994 to 2002). The objective was to determine in-hospital mortality rate among patients who had ST-segment depression on the initial electrocardiogram. Patients who had ST-segment depression had an in-hospital mortality rate (15.8%) similar to that of patients who had ST-segment elevation or left bundle branch block (15.5%). After adjusting for observed differences, ST-segment depression was associated with only a slightly lower odds ratio (0.91) of mortality compared with ST-segment elevation or left bundle branch block.

Quality Improvement Efforts and Hospital Performance

BACKGROUND

Hospitals are under increasing pressure to measure and improve quality of care, and substantial resources are being directed at a variety of quality improvement strategies; however, the evidence base supporting these strategies is limited.

OBJECTIVE

We sought to identify quality improvement efforts that were associated with hospitals' beta-blocker prescription rates after acute myocardial infarction (AMI).

RESEARCH DESIGN

This was a cross-sectional study using data from a telephone survey of quality management directors at participating hospitals linked with patient-level data from the National Registry of Myocardial Infarction (NRMI) during the study period, October 1997 to September 1999.

SUBJECTS

A total of 60,363 patients discharged with a confirmed AMI from 234 US hospitals were included.

MEASURES

Hospital performance based on beta-blocker rates characterized as the top 20%, lower 20%, and middle 40% of hospitals; reported quality improvement efforts, including system interventions, physician leadership, administrative support for quality improvement efforts, and data feedback; hospital teaching status, AMI volume, geographic location, and ownership type.

RESULTS

The mean hospital-specific beta-blocker rate was 60.2%; however, the variation in beta-blocker use across hospitals was marked (range, 19.4-89.3%, standard deviation, 12.7% points), and quality improvement efforts used varied greatly. None of the quality improvement efforts distinguished higher from medium performers; the higher and the medium performers together were distinguished from the lower performers in organizational support for quality improvement efforts (fully adjusted odds ratio [OR] 1.89, 95% confidence interval [CI] 1.17-3.06) and physician leadership (fully adjusted OR 9.88, 95% CI 2.64-37.02). Among the specific quality improvement interventions, only standing orders were associated with having higher/medium versus lower performance, and their effect had borderline significance (fully adjusted OR 2.26, 95% CI 0.97-5.30, P = 0.07).

CONCLUSIONS

Our findings highlight the organizational environment, specifically the absence of administrative support or physician leadership for quality improvement, as an important correlate of poor beta-blocker rates after AMI. Future studies are needed to isolate hospital quality improvement efforts that are associated with superior performance.

Times to Treatment in Transfer Patients Undergoing Primary Percutaneous Coronary Intervention in the United States

BACKGROUND

Treatment delays in patients with ST-segment-elevation myocardial infarction (STEMI) transferred for primary percutaneous coronary intervention (PCI) may decrease the advantage of this strategy over on-site fibrinolytic therapy that has been demonstrated in recent clinical trials. Accordingly, we sought to describe patterns of times to treatment in patients undergoing interhospital transfer for primary PCI in the United States.

METHODS AND RESULTS

We analyzed patients with STEMI undergoing interhospital transfer for primary PCI between January 1999 and December 2002 in the National Registry of Myocardial Infarction. The primary outcome was "total" door-to-balloon time measured from time of arrival at the initial hospital to time of balloon inflation at the PCI hospital. Multivariable hierarchical models were used to assess the relationship of total door-to-balloon time with patient and hospital characteristics. Among 4278 patients transferred for primary PCI at 419 hospitals, the median total door-to-balloon time was 180 minutes, with only 4.2% of patients treated within 90 minutes, the benchmark recommended by national quality guidelines. Comorbid conditions, absence of chest pain, delayed presentation after symptom onset, less specific ECG findings, and hospital presentation during off-hours were associated with longer total door-to-balloon times. Patients at teaching hospitals in rural areas also had significantly longer times to treatment.

CONCLUSIONS

Total door-to-balloon times for transfer patients undergoing primary PCI in the United States rarely achieve guideline-recommended benchmarks, and current decision making should take these times into account. For the full benefits of primary PCI to be realized in transfer patients, improved systems are urgently needed to minimize total door-to-balloon times.

Improving care in patients with acute coronary syndromes: the Erlanger quality improvement initiative

Quality improvement (QI) in emergency department (ED) patients with acute coronary syndromes (ACS) is a complex and dynamic phenomenon. ED physicians are faced with the challenge of multitasking a variety of patient complaints. This chaotic environment frequently hampers the ED physician's ability to properly evaluate and treat chest pain patients. Just as an airplane pilot would never take off without performing the comprehensive preflight operational checklist, the ED physician should have a standardized protocol for the evaluation and treatment of chest pain patients. In this report, we describe Erlanger Medical Center's 10-year QI initiative in developing a successful chest pain protocol for the rapid evaluation and treatment of patients with suspected ACS. Our initiative resulted from a collaborative effort among emergency physicians, cardiologists, nuclear radiologists, nursing staff, and administration. The systematic step-wise approach we utilized at our institution consisted of identification of the problem, development of standardized protocols, hospital-based QI initiatives, and continuation of QI efforts through national initiatives. Through this "building of bridges" among physicians, nursing, and administration, we hope that other institutions will modify our protocols to assist them in the development of their own successful QI program for improving the evaluation, treatment, and disposition of patients with suspected ACS.

Relation of age and race with hospital death after acute myocardial infarction

BACKGROUND

Prior studies have suggested that young blacks with acute myocardial infarction (AMI) may have higher hospital mortality rates than whites of similar age. However, the influence of age and race on short-term death has not been explored in detail. We examined the relation of age and race on short-term death in a large AMI population and ascertained the factors that may have contributed to differences in mortality rates.

METHODS

We compared the crude and adjusted hospital mortality rates stratified by age among 40,903 blacks and 501,995 whites with AMI enrolled in the National Registry of Myocardial Infarction-2 in 1482 participating US hospitals from June 1994 through March 1998.

RESULTS

Overall crude mortality was lower among blacks compared with whites (10.9% vs 12.0%, P <.0001). However, blacks had a significantly higher crude mortality rate compared with the whites in the age groups <65 years (<45 years, and 5-year age groups between 45 and 64 years). There was a statistically significant interaction between age and black race on hospital death (P value for interaction <.001). Each 5-year decrement in age from 85 years was associated with 7.2% higher odds of death in blacks compared with whites (95% CI, 5.7% to 7.6%). After adjusting for differences in the baseline, clinical presentation, early treatment, and hospital characteristics, 5-year decrements in age was still associated with increases in the odds for death in blacks compared with whites (5.4%; 95% CI, 3.6% to 7.2%). This interaction between age and black race was present in both sexes but was stronger among men.

CONCLUSIONS

Blacks younger than 65 years had higher hospital mortality rates compared with whites hospitalized for AMI, and decreasing age was associated with progressively higher risk of hospital death for blacks. Differences in the clinical presentation, early treatment, and hospital characteristics could only partly explain this age-race interaction.