Performance of Management Strategies With Class I Recommendations Among Patients Hospitalized With ST-Segment Elevation Myocardial Infarction in China

Key Points

Question  What are the variations and trends in quality of care for patients hospitalized with ST-segment elevation myocardial infarction (STEMI) in China?

Findings  In this nationwide registry of 57 560 hospitalizations from 143 hospitals between 2014 and 2019, only 20.0% of patients received all clinical treatments for which they were eligible. There were significant hospital variations in all-or-none score and individual measures, but improvements were noted in the quality of care during the study period.

Meaning  Substantial gaps exist between guideline recommendations and clinical practice for patients with STEMI in China, but quality improvement programs may be associated with significantly increased use of Class I treatment recommendations.

Importance  Despite advances in the treatment of ST-segment elevation myocardial infarction (STEMI), little is known about how this evolving knowledge is applied in current clinical practice in China.

Objective  To evaluate hospital performance and temporal trends in the management of STEMI.

Design, Setting, and Participants  This study used data from the Improving Care for Cardiovascular Disease in China–Acute Coronary Syndrome Project, a nationwide quality improvement registry, in collaboration with the American Heart Association and the Chinese Society of Cardiology. Participants included patients with STEMI admitted to 143 tertiary hospitals across China from November 2014 to July 2019, and data were analyzed from November 2020 to December 2021.

Main Outcomes and Measures  Levels, hospital-level variations, and trends for utilization rates of the 9 management strategies with Class I recommendations in Chinese and US guidelines.

Results  A total of 57 560 hospitalizations with STEMI were included. Overall, 20.0% of patients received all the care according to the 9 guideline-recommended strategies. The performance rate of quality measures was low for reperfusion therapy (61.0%, 35 115/57 560 patients), β-blocker at discharge (68.3%, 37 750/55 285 patients), angiotensin-converting enzyme inhibitor or angiotensin receptor blocker at discharge (55.1%, 2524/4578 patients), and smoking cessation counseling (36.5%, 9586/26 265 patients) among those who were eligible. Of 25 563 patients who underwent primary percutaneous coronary intervention (PCI), 66.8% underwent this procedure within 90 minutes of hospital arrival. Of 1128 patients who underwent fibrinolysis therapy, 253 (22.4%) underwent this treatment within 30 minutes of hospital arrival. Measures with high performance rates included receipt of dual antiplatelet therapy within 24 hours (95.5%, 54 263/56 848 patients) and at discharge (91.8%, 51 452/56 019 patients) and receipt of statin at discharge (93.0%, 52 214/56 141 patients) for those eligible. There was significant variation between hospitals in all-or-none score (ranging from 0 to 61.9%) and performance of individual measures. The quality of care improved during the study period, especially for reperfusion therapy, primary PCI within the first 90 minutes of hospital arrival, and smoking cessation counseling.

Conclusions and Relevance  The quality of care for patients hospitalized with STEMI does not meet guideline-recommended strategies in China, with only 1 in 5 patients receiving all the care according to the 9 guideline-recommended strategies. Large disparities in the quality of care exist across hospitals.

Ischemic heart disease is a major cause of death in China, leading to an estimate of 1.87 million deaths and loss of 34.69 million disability-adjusted life-years in 2019.^1-3 ST-segment elevation myocardial infarction (STEMI) is a severe acute manifestation of ischemic heart disease with substantial morbidity and mortality.

Abundant evidence from randomized clinical trials confirms the efficacy of several strategies for acute treatment and secondary prevention of STEMI, including use of reperfusion therapy, antithrombotic therapy, and lipid-lowering medications, which reduce mortality and the risk of recurrent events when used according to recommendations from clinical practice guidelines.^4,5 These evidence-based management strategies are classified as Class I recommendations in Chinese Society of Cardiology (CSC), American College of Cardiology (ACC)/American Heart Association (AHA), and European Society of Cardiology guidelines for the management of hospitalized patients with STEMI. Implementation of these evidence-based management strategies in eligible patients with STEMI can improve patient outcomes. The ACC/AHA and other organizations developed sets of performance metrics to promote translation of established evidence into clinical practice.^6,7 The ACC/AHA 2017 Clinical Performance and Quality Measures for Patients with Acute Myocardial Infarction provided critically important tools for measuring quality of care and identifying opportunities for improvement.⁷ Although a few studies in China have shown that gaps exist between clinical practice and treatment guidelines in patients with STEMI,^8-10 updated information about performance variations and trends in quality of care for patients hospitalized with STEMI in China is still needed.

The AHA and the CSC launched the Improving Care for Cardiovascular Disease in China (CCC)–Acute Coronary Syndrome (ACS) Project in 2014, focusing on quality improvement efforts for ACS care in China. We systematically evaluated the quality of care of 57 560 patients hospitalized with STEMI in China and examined variations across the 143 participating hospitals. This study also examined temporal trends in quality of care and patient characteristics associated with Class I recommendation management strategies with low utilization rates for patients with STEMI.

The CCC-ACS Project is a nationwide quality improvement registry program focusing on quality improvement of care for patients with ACS. As a collaborative initiative of the AHA and the CSC, the CCC-ACS Project was launched in 2014. The details of the design and methodology of the CCC-ACS Project have been published previously.¹¹ Phases 1 and 2 of the project included 150 tertiary hospitals across China. During phase 3 and phase 4, an additional 82 secondary hospitals and 8 new tertiary hospitals were enrolled from 2017. Each month, the first 20 to 30 and 10 to 20 consecutive patients with ACS were recruited to the study from tertiary and secondary hospitals, respectively. Patients with STEMI were enrolled based on the principal discharge diagnosis by reviewing the inpatient list. Institutional review board approval was granted for this research with a waiver of informed consent by the ethics committee of Beijing Anzhen Hospital, Capital Medical University. This study is registered with ClinicalTrials.gov (NCT02306616).

From November 2014 to July 2019, 57 758 hospitalizations with STEMI from 158 tertiary hospitals were enrolled based on their principal discharge diagnosis. After excluding 198 patients from 15 hospitals reporting fewer than 50 cases during the study period, 57 560 hospitalizations with STEMI from 143 tertiary hospitals were included. In the current study, patients with first and recurrent STEMI with acute event were included. Data were analyzed from November 2020 to December 2021.

Clinical data from medical records were reported via a web-based data collection platform (Oracle Clinical Remote Data Capture, Oracle Corporation) by trained data abstractors at participating hospitals. Data elements collected in this study included patient demographics, medical histories, symptoms on arrival, in-hospital treatments and procedures, discharge medications, and secondary prevention strategies. Eligible patients during each month were entered into the online data reporting system in a consecutive manner before the middle of the following month after discharge. Four approaches were adopted to secure the accuracy and completeness of data, including face-to-face training workshops, standardized online reporting with automatic checks for invalid values, on-site quality control, and monitoring of data completeness.

We evaluated the use of 9 therapies with a Class I recommendation in the 2015 STEMI guidelines issued by the CSC,¹² which coincide with those in ACC/AHA guidelines.⁴ These recommendations are as follows: (1) reperfusion therapy in the acute phase, (2) thrombolysis within the first 30 minutes of hospital arrival among patients undergoing thrombolysis, (3) percutaneous coronary intervention (PCI) within the first 90 minutes of hospital arrival among patients undergoing primary PCI, (4) receipt of dual antiplatelet therapy (DAPT) within 24 hours of hospital arrival, (5) prescription of DAPT at discharge, (6) prescription of β-blocker therapy at discharge after STEMI for patients without documented contraindication, (7) prescription of statins at discharge, (8) prescription of an angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) at discharge after STEMI for patients with left ventricular ejection fraction 40% or less, and (9) smoking cessation counseling during hospitalization. For each treatment, specialized inclusion and exclusion criteria were used, and only appropriate patients with no contraindications were counted as denominators (eTable 1 in Supplement 1). The patients who left against medical advice were not excluded from the denominators. The all-or-none score was defined as proportion of patients who received all of the performance measures for which the patient was eligible, based on these 9 management strategies.¹³ Definitions for other study variables are provided in the eAppendix in Supplement 1.

Several quality improvement tools were developed and applied to help cardiologists improve their adherence to guideline recommendations for patients with ACS in daily clinical practice. These tools included monthly hospital quality reports, annual hospital recognition, regional workshops, and online educational materials, which are described in detail elsewhere.^11,14 Monthly hospital quality reports outlined the proportion of patients receiving management for each of the performance measures, showed a comparison with mean performance at all other centers, and provided an anonymized ranking from the lowest performance to the highest performance among all participating hospitals.

Categorical variables are presented as frequency and percentage, while continuous variables are presented as mean (SD) or median (IQR). The significance of differences in categorical variables was tested by the χ² test. The unpaired t test or the Mann-Whitney U test was used to test for statistically significant differences between the mean or median where appropriate. Trends over the years in all-or-none score and the performance rate of individual measures were assessed using the Cochran-Mantel-Haenszel test.

For variables with missing values, IVEware version 0.2 (Survey Research Center, University of Michigan) was used to impute the missing values with the sequential regression multiple imputation method. Missing rates of each variable and management of missing data are shown in eTable 2 in Supplement 1. Variables without any missing data were not listed. Statistical analyses were based on individual hospitalizations and performed using SAS version 9.2 (SAS Institute). A 2-sided P value less than .05 was considered statistically significant.

A total of 57 560 hospitalizations with STEMI from 143 participating hospitals across China were included in this study. Table 1 presents the clinical characteristics of patients with STEMI overall and stratified by sex. The mean (SD) age of patients was 61.8 (12.6) years, and 45 145 (78.4%) were men. The median (IQR) hospital stay was 9 days (7-13) among all patients. There was substantial variation in median for length of stay across hospitals, ranging from 5 to 17.5 days (eFigure 1 in the Supplement). The median (IQR) time from symptom onset to hospital admission was 5.9 hours (2.8-17.0). For biomarkers of myocardial necrosis, 45 242 of 57 560 patients (78.6%) had severely increased concentrations of troponin T, troponin I, and creatine kinase MB (CK-MB). Patients with STEMI had a high prevalence of concomitant disease, with 16 238 (28.2%) having diabetes, 26 575 (46.2%) being smokers, 35 423 (61.5%) having hypertension, and 49 543 (86.1%) having an elevated low-density lipoprotein cholesterol (LDL-C) concentration. In addition, 3083 (5.4%) patients with STEMI exhibited recurrence, 14 930 (25.9%) had chronic heart failure, and 8344 (14.5%) had chronic kidney disease.

Among patients with STEMI in the CCC-ACS Project, the overall all-or-none score for the 9 management strategies (Class I recommendations) recommended by CSC and AHA/ACC guidelines was 20.0% (Figure 1). There was significant hospital variation in all-or-none score (median, 17.1%; IQR, 9.8%-23.8%; range, 0-61.9%). At only 4 hospitals did more than half of patients receive care according to all 9 strategies. All-or-none scores for patients with STEMI across subgroups are presented in eTable 3 in Supplement 1. Patients with a high quality of care were more likely to be men, be younger, have a high level of medical insurance reimbursement, and be experiencing their first STEMI event.

In addition to evaluating all-or-none score for the 9 management strategies, this study analyzed the quality of care and hospital-level variations in performance of each of the 9 measures (Figure 2 and eFigure 2 in Supplement 1).

Reperfusion therapy was performed in 35 115 of 57 560 patients (61.0%) with STEMI. The treatment rates of reperfusion varied greatly among hospitals, with a median rate of 60.3% (IQR, 47.8%-74.0%; range, 16.5%-98.2%). Among 35 115 patients who underwent reperfusion therapy, 30 936 (88.1%) underwent primary PCI alone, 3168 (9.0%) received fibrinolytic therapy alone, and 1011 (2.9%) were treated with a combination of fibrinolytic therapy and PCI. Patients undergoing primary PCI were more likely to be male, be younger, and have a high level of medical insurance reimbursement according to the logistic regression analysis (Table 2). Among 25 563 patients who underwent primary PCI and for whom time information was available, 17 067 (66.8%) underwent primary PCI within 90 minutes of hospital arrival. The median rate of primary PCI within 90 minutes of hospital arrival among hospitals was 63.5% (IQR, 50.0%-74.7%; range, 0-95.7%). Among 1128 patients who underwent fibrinolysis therapy and for whom time information was available, 253 (22.4%) underwent this treatment within 30 minutes of hospital arrival. The median rate for this indicator among hospitals was 12.9% (IQR, 0-33.3%; range, 0-100%).

Adherence to clinical guidelines was low for ACEIs/ARBs at discharge (55.1%, 2524/4578 patients), β-blockers at discharge (68.3%, 37 750/55 285 patients), and smoking cessation counseling (36.5%, 9586/26 265 patients) in patients with indications. There was significant hospital variation in the use of ACEI/ARB at discharge (IQR, 36.6%-65.8%; range, 0-100%), β-blockers at discharge (IQR, 54.4%-78.4%; range, 12.5%-97.1%), and smoking cessation counseling (IQR, 6.9%-57.4%; range, 0-100%). Patients who were prescribed β-blockers at discharge according to indication were more likely to be younger; have a high level of medical insurance reimbursement; have diabetes, hypertension, history of myocardial infarction, and elevated LDL-C concentration; and be less likely to present with cardiac shock at admission (eTable 4 in Supplement 1). Patients who were prescribed ACEI/ARB at discharge according to indication were more likely to be male, be younger, and have diabetes and hypertension and were less likely to have chronic kidney disease and present with cardiac shock at admission (eTable 5 in Supplement 1).

Measures with high performance rates included DAPT (aspirin combined with P2Y12 inhibitors) at arrival (54 263/56 848 patients; 95.5%; IQR, 93.4%-98.6%; range, 67.8%-100%), DAPT at discharge (51 452/56 019; 91.8%; IQR, 88.3%-96.8%; range, 35.0%-100%), and statins at discharge (52 214/56 141; 93.0%; IQR, 89.4%-97.1%; range, 37.2%-100%). Among 16 471 patients with detailed information on statin dosage at discharge, 90.9% were prescribed moderate doses, 8.2% high doses, and 0.9% low doses.

There was a significant improvement in care for patients hospitalized with STEMI from 2014 and 2015 (data were combined for 2 these years) to 2019, especially for those undergoing reperfusion therapy, PCI within the first 90 minutes of hospital arrival, thrombolysis within the first 30 minutes of hospital arrival, and smoking cessation counseling before hospital discharge (Figure 3). For measures with high performance rates (>90%) in the first year, including statins at discharge, DAPT at arrival, and DAPT at discharge, smaller absolute improvements or even no improvements were observed in the performance rates. The proportion of eligible patients receiving all of the 9 CSC and AHA/ACC guideline-recommended therapies improved from 16.1% to 28.9% during the study period (P for trends < .001). Temporal trends for hospital-level all-or-none score and individual measures across hospitals are shown in eTable 6 in the Supplement. Density plots of hospital-level all-or-none scores in the combined 2014/2015 and 2019 indicated that the improvement in all-or-none score across hospitals during the study period was more likely due to a rightward shift of the entire distribution (eFigure 3 in the Supplement).

In this large nationwide registry of hospitalized patients with STEMI in China, only 20.0% of patients received care according to all 9 of the guideline-recommended strategies, with substantial variability across hospitals. Only 1 in 5 patients admitted to hospital for STEMI in China received all clinical treatments for which they were eligible, suggesting there are substantial opportunities to further improve the quality of care and potentially improve the clinical outcomes for these patients. The study also suggested that substantial improvement occurred in hospital-based acute care and secondary prevention for STEMI across hospitals.

The marked underuse of guideline-recommended management strategies calls for further quality improvement in China. Identifying the underlying reasons for underuse of these evidence-based management strategies is essential to improve the quality of, and reduce disparities in, STEMI treatment. Specially targeted quality improvement efforts will help narrow the disparities in quality of care and outcomes in patients with STEMI.

The performance rates of reperfusion therapy, thrombolysis within the first 30 minutes of arrival, primary PCI within the first 90 minutes of arrival, β-blocker therapy at discharge, ACEI/ARB therapy at discharge, and smoking cessation counseling were relatively low with marked hospital variation. In our study, approximately 60% of patients hospitalized with STEMI underwent reperfusion therapy, which is much lower compared with that reported in the United States and Europe.^15,16 Underuse of these treatments may be related to uncertainty about identifying patients with indications, variations in the capacity of clinical services, balancing the benefits and risks of therapy, and high out-of-pocket costs.¹⁷ Collectively, these findings suggest an important opportunity to improve the overall care and reduce the inequality across hospitals for patients with STEMI in China.

Moreover, we noticed that substantial variability existed in delivery of evidence-based measures for patients with STEMI across hospitals in China. The disparity in quality of care across hospitals was reflected in both all-or-none score and individual management strategies, especially primary PCI, β-blocker therapy at discharge, and ACEI/ARB therapy at discharge. The proportion of eligible patients receiving these evidence-based treatments was associated with patient characteristics, such as age, type of medical insurance, comorbidities, and severe clinical conditions at admission. Geographic (eastern, central, and western) variations and hospital-level (province-level, prefecture-level, and county-level) differences were also observed in the Patient-Centered Evaluative Assessment of Cardiac Events–Retrospective Acute MI Project and China Acute Myocardial Infarction Registry.^18,19 A recent study from Acute Coronary Treatment and Intervention Outcomes Network Registry–Get With The Guidelines (ACTION Registry-GWTG) revealed that the choice of admission hospital can affect patients’ adherence to cardiac secondary prevention treatment.²⁰ Use of secondary prevention treatments varied significantly across hospitals in the United States and was inversely associated with long-term cardiovascular outcomes.²⁰ Taken together, delivery of uniformly high-quality management for patients with STEMI will improve patient outcomes.

In the current study, a substantial and sustained improvement was observed in all-or-none score, as well in the performance of several acute management and secondary prevention measures for patients with STEMI over the last 5 years. This study showed that the CCC-ACS quality improvement project can improve care for patients with STEMI across the country. Effective reperfusion therapy can reduce myocardial necrosis and significantly improve the prognosis of patients with STEMI. An increase in the reperfusion therapy rate of 10% at participating hospitals is expected to substantially reduce the number of deaths among patients hospitalized with STEMI. Moreover, even a modest improvement in the use of other guideline-recommended therapies will translate into thousands of care opportunities, considering the large number of patients with STEMI hospitalized in CCC-ACS hospitals each year.

Performance improvement varied across these measures, with reperfusion therapy, PCI within the first 90 minutes of hospital arrival, thrombolysis within the first 30 minutes of hospital arrival, and smoking cessation counseling showing the highest absolute percentage change. Smaller absolute improvements (≤1%) were observed in performance measures with a high performance (>90%) in the first year.

We noticed that patients took a much longer average time to reach the hospital (median 5.9 hours) compared with US and European counties (range, 2.3-2.8 hours).^15,21 Most patients reached hospital by public or private transport instead of by ambulance. The reasons patients reached the hospital late may include a lack of awareness of STEMI symptoms, economic reasons, bad traffic in urban areas, and scarcity of efficient transportation in rural areas. Moreover, the median hospital stay (9 days) was much longer compared with that in developed counties (range, 4-7 days).^21-23 The prolonged hospital stay in China may be explained by the fact that a proportion of patients with STEMI received elective PCI that was performed more than 3 days after admission.

The results of this study should be interpreted in consideration of several limitations. First, participation in the study was voluntary, which may have introduced potential selection bias. Thus, the current results may not be representative of hospitals that did not join the project. However, hospitals in the CCC-ACS Project were recruited by geographic and economic regions and represented the diversity of STEMI care in hospitals across China. Second, as clinical information was abstracted from inpatient records, the quality of documentation had a potential influence on the current study.

There are substantial gaps between guideline recommendations and clinical practice for patients hospitalized with STEMI in China, even among tertiary hospitals. Only 1 in 5 patients received all the care according to the 9 guideline-recommended strategies. Quality improvement programs significantly increased the use of Class I treatment recommendations during the study period.

Accepted for Publication: December 21, 2021.

Published Online: March 16, 2022. doi:10.1001/jamacardio.2022.0117

Corresponding Authors: Yaling Han, MD, Cardiovascular Research Institute and Department of Cardiology, General Hospital of Northern Theater Command, 83 Wenhua Rd, Shenyang 110016, Liaoning, China (hanyaling@263.net); Sidney C. Smith Jr, MD, Division of Cardiology, Department of Medicine, University of North Carolina, 130 Dental Cir, Burnett-Womack Building, CB 7075, Chapel Hill, NC 27599-7075 (scs@med.unc.edu).

Author Contributions: Drs Han and Smith had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Hao, Zhao, Jing Liu, Huo, Fonarow, Ge, Ma, Smith.

Acquisition, analysis, or interpretation of data: Hao, Zhao, Jing Liu, Jun Liu, Yang, Fonarow, Morgan, Han, Smith.

Drafting of the manuscript: Hao.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Hao.

Obtained funding: Morgan.

Administrative, technical, or material support: Hao, Zhao, Jing Liu, Jun Liu, Yang, Huo, Ma, Han.

Supervision: Zhao, Jing Liu, Ge, Smith.

Conflict of Interest Disclosures: Dr Hao reported grants from American Heart Association during the conduct of the study. Dr Zhao reported grants from American Heart Association during the conduct of the study. Dr Jing Liu reported grants from American Heart Association during the conduct of the study. Dr Jun Liu reported grants from American Heart Association during the conduct of the study. Dr Fonarow reported personal fees from Abbott, Amgen, AstraZeneca, Bayer, Cytokinetics, Janssen, Medtronic, Merck, and Novartis outside the submitted work and reported being associate section editor, JAMA Cardiology. Ms Morgan reported grants from Pfizer and AstraZeneca during the conduct of the study. Dr Ma reported personal fees from Bristol Myers Squibb, Pfizer, Johnson & Johnson, Bayer, and Boehringer-Ingelheim for giving lectures outside the submitted work. No other disclosures were reported.

Funding/Support: The CCC-ACS Project is a collaborative project of the American Heart Association and the Chinese Society of Cardiology. The AHA received funding from Pfizer through an independent grant for learning and change and AstraZeneca as a quality improvement initiative.

Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

The CCC-ACS Investigators: The CCC-ACS investigators and participating centers are listed in Supplement 2.

Additional Contributions: We acknowledge all participating hospitals for their data contribution to the CCC-ACS Project. We thank Emily Woodhouse, PhD, from Liwen Bianji (Edanz) (www.liwenbianji.cn/ac), for editing the English text of a draft of this article. She received compensation for her contribution.