Article Text

Original research
Quality of healthcare and admission rates for acute cardiac events during COVID-19 pandemic: a retrospective cohort study on ST-segment-elevation myocardial infarction in China
  1. Junxiong Ma1,2,
  2. Shuduo Zhou1,2,
  3. Na Li1,2,
  4. Xuejie Dong1,2,
  5. Mailikezhati Maimaitiming1,2,
  6. Dahai Yue3,
  7. Yinzi Jin1,2,
  8. Zhi-Jie Zheng1,2,4
  1. 1Department of Global Health, School of Public Health, Peking University, Beijing, China
  2. 2Institute for Global Health and Development, Peking University, Beijing, China
  3. 3Department of Health Policy and Management, University of Maryland at College Park, College Park, Maryland, USA
  4. 4Bill & Melinda Gates Foundation China Office, Beijing, China
  1. Correspondence to Dr Yinzi Jin; yzjin{at}bjmu.edu.cn

Abstract

Objective To evaluate changes in admission rates for and quality of healthcare of ST-segment-elevation myocardial infarction (STEMI) during the period of the COVID-19 outbreak and postoutbreak.

Methods We conducted a retrospective study among patients with STEMI in the outbreak time and the postoutbreak time.

Design To examine the changes in the admission rates and in quality of healthcare, by comparison between periods of the postoutbreak and the outbreak, and between the postoutbreak and the corresponding periods.

Setting Data for this analysis were included from patients discharge diagnosed with STEMI from all the hospitals of Suzhou in each month of the year until the end of July 2020.

Participants 1965 STEMI admissions.

Primary and secondary outcome measures The primary outcome was the number of moecondary outcomnthly STEMI admissions, and the secondary outcomes were the quality metrics of STEMI healthcare.

Results There were a 53% and 38% fall in daily admissions at the phase of outbreak and postoutbreak, compared with the 2019 corresponding. There remained a gap in actual number of postoutbreak admissions at 306 and the predicted number at 497, an estimated 26 deaths due to STEMI would have been caused by not seeking healthcare. Postoutbreak period of 2020 compared with corresponding period of 2019, the percentage of cases transferred by ambulance decreased from 9.3% to 4.2% (p=0.013), the door-to-balloon median time increased from 17.5 to 34.0 min (p=0.001) and the rate of percutaneous coronary intervention (PCI) therapy declined from 71.3% to 60.1% (p=0.002).

Conclusions The impact of public health restrictions may lead to unexpected out-of-hospital deaths and compromised quality of healthcare for acute cardiac events. Delay or absence in patients should be continuously considered avoiding the secondary disaster of the pandemic. System delay should be modifiable for reversing the worst clinical outcomes from the COVID-19 outbreak, by coordination measures with focus on the balance between timely PCI procedure and minimising contamination of cardiac catheterisation rooms.

  • COVID-19
  • Myocardial infarction
  • Quality in health care

Data availability statement

Data may be obtained from a third party and are not publicly available. Data for this study were obtained from the China Chest Pain Center Database (http://data.chinacpc.org/), a nationwide clinical registry for collecting data of all consecutive patients diagnosed with STEMI enrolled by hospitals. The data management committee, one of the committees of the management board was responsible for evaluating and monitoring the Date.

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STRENGTHS AND LIMITATIONS OF THIS STUDY

  • This study is the first study to examine the changes in the admission rates and in quality of healthcare between the postoutbreak and the corresponding periods in China, with the fading of the COVID-19 outbreak.

  • Our confidence in the findings is further increased by Holt-Winters Exponential smoothing analysis, stable sensitivity analyses.

  • This study was limited to Suzhou, which limits the generalisability of the results.

  • It is a dynamic retrospective study, there would be concerns related to confounding, bias and temporal trends in quality of healthcare that might limit the validity of the findings.

Introduction

The COVID-19 pandemic is challenging healthcare delivery systems in unprecedented ways, and the effects will last for decades to come.1 Most countries have implemented stringent infection-control measures, including but not limited to social distancing measure, emergency infection protocols instituted in hospitals to contain COVID-19, and adjustment of clinical services. The response to outbreak can compromise quality of healthcare for non-coronavirus diseases, especially for ST-segment-elevation myocardial infarction (STEMI), the deadliest and most time-sensitive acute cardiac event.2–4 A number of studies have reported substantial declines in the number of patients presenting with STEMI and the rate of percutaneous coronary intervention (PCI), the typically recommended treatment, during the outbreak.5–9 However, little is known regarding the impact of the postoutbreak on admission rate and healthcare quality for STEMI.

China has recovered from the initial outbreak and is experiencing the defence of the coronavirus bounce back. There are two major public health concerns with respect to STEMI healthcare in the postoutbreak time: (1) delays in presentation and (2) delays in treatment.10–12 First, less is clear on whether there has been a rebound in STEMI presentation. Several studies have reported a surge in STEMI admission rate correlating with the fading of the first wave of the COVID-19 outbreak.13 Changes in lifestyle pattern (eg, physical inactivity and weight gain) during lockdown, has been suggested as a potential factor for exacerbating the population cardiovascular risk profile and creating a greater number of vulnerable coronary patients.14 15 Even yet in the period of postoutbreak, the emphasis on social distancing might have inappropriately convinced patients to avoid in-person healthcare. The lack of knowledge on personal protection measures compounded by fear of contracting an infection may make patients much less likely to seek help. Thus, an increasing number of patients presenting with STEMI at high coronary risk do not seek healthcare in a timely manner, which will lead to more unexpected out-of-hospital deaths and cause the secondary disaster of the outbreak.

Second, little is known regarding how the postoutbreak influenced the delivery of STEMI healthcare in terms of clinical services and processes based on the recommended guidelines. STEMI cases require rapid coordination of care beginning at the time once patients enter the healthcare delivery system. However, the emergency infection protocols (eg, coronavirus screening on hospital arrival) still persistent, which could result in a considerable delay in timely treatment, and may impact optimal treatment delivery for patients presenting with STEMI.16 17 It is a great challenge for healthcare delivery system to make a balance between identifying patients for PCI procedure, regardless of their coronavirus status, and maintaining the safety of healthcare workers who may be exposed to the virus as well as minimising contamination of cardiac catheterisation rooms. Thus, it is warranted to evaluate how is the healthcare delivery system’s resilience to recover from the coronavirus outbreak, for operational integrity with respect to STEMI cases.

To fill this gap, this study aims to investigate the admissions for and quality of healthcare of STEMI in the postoutbreak time. The objectives of this study are twofold as follows: (1) to examine the changes in the admission rates, by comparing the numbers in the outbreak and postoutbreak with the predicted numbers based on the admissions in 2017–2019; (2) to investigate the changes in quality of healthcare, by comparison between periods of the postoutbreak and the outbreak, and between the postoutbreak and the corresponding periods in 2017–2019.

Materials and methods

Data statement

Data for this study were obtained from the China Chest Pain Center Database (http://data.chinacpc.org/), a nationwide clinical registry for collecting data of all consecutive patients diagnosed with STEMI enrolled by hospitals. The data management committee, one of the committees of the management board was responsible for evaluating and monitoring the data.18 All the accredited Chest Pain Centers in Suzhou were instructed to submit consecutive eligible patients to the Database. The data elements include patient demographics, prehospital treatment, presenting features, in-hospital medication and reperfusion practice, clinical outcomes and discharge. This national audit is supervised by the National Health Commission. Hospitals are instructed to submit consecutive eligible patients to the database in real time. Improvement in adherence to data reporting is facilitated through monthly and quarterly hospital-specific performance feedback reports. We extracted the data from all the hospitals with capacity of PCI therapy in the city of Suzhou (Represents China’s second-tier cities, mainly urban areas), which has been one of the pilot cities to implement the highest restrictions of lockdown. Suzhou has also taken the lead to announce the unlock and resumption of routine work and industry production.

Study design

We conducted a retrospective study of patients presenting with STEMI between January 2017 and July 2020. The outbreak time was defined as the period between 23 January 2020 and 27 March 2020, corresponding to the promulgation of the highest restrictions of movement and a public health drive to combat rising cases in Suzhou. The postoutbreak time was defined as the period between 28 March 2020 and 31 July 2020 corresponding to the announcement of resumption of daily work and industry production by Suzhou government. The corresponding periods are defined as the same time quantum in 2017, 2018 and 2019. Data for this analysis were included from patients discharge diagnosed with STEMI from all the hospitals of Suzhou in each month of the year 2017–2019 until the end of July 2020.

Measures

The primary outcome was the number of monthly STEMI admissions, and the secondary outcomes were the quality metrics of STEMI healthcare in terms of prehospital process, in-hospital process and clinical outcome. The quality metrics were selected, based on the class I recommendations from the most updated American College of Cardiology/American Heart Associatio clinical practice guidelines (online supplemental table 1).19

The prehospital process indicators included percentage of onset-to-first medical contact (FMC) time ≤60 min, percentage of ambulance ECG to door time ≤15 min, percentage of cases arriving at hospital by ambulance, percentage of ambulance ECG. The in-hospital process indicators included percentage of β-blocker usage, percentage of door-to-balloon time ≤60 min, percentage of FMC-to-device time ≤90 min, percentage of onset-to-device time ≤120 min, door-to-balloon time, FMC-to-device time, onset-to-device time and PCI rate. The clinical outcome indicator was in-hospital mortality.

Demographic and clinical characteristics for this study included age, sex, presenting chest pain status, vital signs (respiratory rate, pulse frequency, heart rate, blood pressure) and Killip class.

Statistical analysis

A descriptive analysis presented the daily admission rates and median monthly onset-to-PCI time of STEMI patients over the periods of the postoutbreak time to the corresponding period in 2017–2019. To provide a more intuitive interpretation of unexpected out-of-hospital deaths, we predicted the number of admissions that should be in the postoutbreak time based on the numbers over the corresponding periods in 2017–2019 by the method of Holt-Winters exponential smoothing after time series analysis, and computed the gap between the actual number and predicted number of admissions.

Holt-Winters Exponential smoothing is a common forecasting algorithm which weighted average of past observations with exponentially decaying weights to capture the trend in a time-series dataset.20 The component form of the addition model is:

Embedded Image

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Where k is the integral part of (h−1)/m, which ensures that the estimates of the seasonal index used for the prediction are from the last year of the sample. Level equations of the ‘t’, means the weighted average of seasonal adjustment of observations (Embedded Image) and non-seasonally adjusted observations (Embedded Image). The trend equation is the same as Holt linear method. The weighted mean seasonality equation represents the current seasonality index, (Embedded Image), A weighted average of the seasonal index from the same season last year (m time periods ago).

The smoothing parameters were automatically generated prior modelling with Holt-Winters method. The α (level), β (slope) and γ (st) of trend should lie between 0 and 1, with values closer to 0 implying that the estimates at the current/future time points are based on recent observations.21 The predicated death number due to the lack of seeking healthcare was calculated by the forecast formula: (predicated numbers − actual numbers) × 8% (average death rate in China).22 23

To examine changes in quality metrics of STEMI healthcare, we compared the list of indicators in terms of prehospital process, in-hospital process and clinical outcome, by a subsample of respective periods, including the outbreak period and the corresponding periods in 2019 and 2018, the postoutbreak period and the corresponding periods in 2019 and 2018. To test the robustness of our findings, we conducted two step of sensitivity analyses. First, we found the estimated trend of the time series was drawn by the function to determine the seasonality of the model (online supplemental figure 1). Then, repeated Holt-Winters exponential smoothing was employed after time series analysis by monthly data to verify the stability of data and consistency of results (online supplemental figure 2). Changes in quality metrics were assessed using univariate analyses, including the Kruskal-Wallis test, χ2 test, t-test and one-way analysis of variance. Fisher’s exact test was used to compute 95% CI for each quality metric. P values <0.05 were considered statistically significant. All statistical analyses were conducted in R software (R Foundation for Statistical Computing, Vienna, Austria and V.3.6.3).

Patient and public involvement

Patients and the public were not directly involved in the study.

Results

Patient characteristics

The study comprised 1965 admissions for STEMI, of which 121 and 306 were in the outbreak and the postoutbreak time, respectively. Of those 306 patients in the postoutbreak time, 17.6% were women, with a mean age of 60.7 (SD 14.6) years. During the outbreak, 26.4% of patients were women and the mean age was 65.2 (SD 12.3), significantly higher (p=0.008, p=0.005) than those in the postoutbreak time, respectively (table 1).

Table 1

Characteristic of STEMI patients during the outbreak and the postoutbreak, compared with corresponding periods in 2018 and 2019

Daily admissions for STEMI

Figure 1 demonstrates daily admissions for STEMI over the periods of outbreak and postoutbreak to the corresponding time in 2018 and 2019. The percentage reduction in admissions were 57% and 55% between the outbreak and the corresponding periods in 2018 and 2019, respectively, with the 2018 and 2019 baseline number of 280 and 267 admissions falling to 121. This decline was partly reversed in the postoutbreak time, such that there were 306 admissions, representing a 42% and 34% reduction from 2018 and 2019 baseline.

Figure 1

Daily admissions to hospitals among patients diagnosed with STEMI in Suzhou of China. STEMI, ST-segment-elevation myocardial infarction.

Figure 2 shows predicated number of daily admissions for STEMI during the outbreak and the postoutbreak. After Holt-Winters exponential smoothing, the smoothing parameters are α=0.27, β=3 × 10−4, γ=0.23. Prediction based on level (α), trend (β) and seasonal (γ) parameters, all of them are relatively between 0–1 and closer to 0, which reflects that the model is relatively stable and the predictions are more reliable. The predicted numbers of admissions for STEMI that might be in the outbreak and the postoutbreak time was 259 and 497. There were a 53% and 38% decline in admissions, with the actual numbers of 121 and 306. Predicated numbers of monthly admissions for STEMI are shown in online supplemental table 2. Based on the forecast formula, the predicted death number due to STEMI caused by the lack of seeking healthcare was 26.

Figure 2

Predicated monthly admissions for STEMI in Suzhou of China. STEMI, ST-Segment-elevation myocardial infarction.

Quality metrics of STEMI healthcare

Figure 3 presents the median monthly treatment delay for STEMI healthcare, by patient delay, transfer delay and in-hospital delay. The median (q1, q3) monthly time from onset to PCI were 179 (86, 622), 169 (89, 350), 159 (76, 622) and 152 (80, 296) min between April and July 2020, significantly higher than those in the corresponding months of 2019 at 156 (88, 328), 144 (65, 287), 150 (80, 316) and 139 (60, 456) min, although those were lower than the number of 210 (78, 511), 230 (113, 662) and 293 (118, 521) min, between January and March 2020.

Figure 3

Monthly mean delay time for healthcare of STEMI, by patient delay, transfer delay and in-hospital delay in Suzhou of China. STEMI, ST-segment-elevation myocardial infarction.

Table 2 shows the changes in quality metrics of healthcare, by comparison between periods of the postoutbreak and the outbreak, and between the postoutbreak and the corresponding periods in 2018–2019. The percentage of STEMI cases transferred by ambulance was both 4.2% in the outbreak and postoutbreak time, respectively, lower than those in the corresponding period of 2019 (16.9%, p=0.005; 9.3%, p=0.013). During the postoutbreak to the corresponding period of 2019, the door-to-balloon and the FMC-to-device median (q1, q3) time increased from 17.5 (10.0, 46.0) and 52.0 (12.0, 886.0) min to 34.0 (15.0, 46.0) and 63.0 (15.0, 94.0) min, respectively (p<0.001, p=0.004), and rate of PCI therapy declined from 71.3% to 60.1% (p=0.002), accompanied by the in-hospital mortality increasing from 2.8% to 4.1%, although it was insignificant. Changes in all the quality metrics of STEMI healthcare between the outbreak and postoutbreak time showed insignificant, with the percentage of cases transferred by ambulance, the percentage of onset-to-FMC time ≤60 min, the percentage of onset-to-device time ≤120 min, and the PCI rate decreasing, and the door-to-balloon time increasing.

Table 2

Quality metrics of STEMI healthcare during the outbreak and the postoutbreak, compared with corresponding periods in 2018 and 2019

Discussion

Principal findings

This is, to our knowledge, the first study to investigate the changes in admissions for and quality of healthcare among acute cardiac events in the postoutbreak time, with the fading of the COVID-19 outbreak. In this study, the Holt-Winters exponential smoothing analysis was used to effectively predict the number of admissions in 2019–2020 and estimate the gap by adding seasonal parameters. Although we observed the reversed increase in STEMI admissions, there remained a gap in the number of the postoutbreak time and predicted numbers based on the admissions in 2018–2019. We explored to predict that 26 deaths due to STEMI would have been caused by not seeking healthcare, while no one died from COVID-19 in the postoutbreak time in the city of Suzhou. According to the incidence of STEMI about 55/100 000 in China, it can be predicated that there will be nearly 300 000 STEMI not seeking healthcare, which could lead to over 20 000 death during the postoutbreak of study.23 Quality of STEMI healthcare remained suboptimal in the postoutbreak time, comparing with those in the corresponding periods in 2018–2019, especially for the percentage of cases transferred by emergency medical service (EMS), and the in-hospital process indicators. Although the in-hospital mortality declined during the outbreak to the postoutbreak, the change was not significant. These findings suggest that the impact of public health restrictions in the postoutbreak time is still significant, and may lead to unexpected out-of-hospital deaths and compromised quality of healthcare for acute cardiac events.

Our findings on the impact of the COVID-19 outbreak are consistent with prior studies that have already reported on decline in admission rate and prolonged time to PCI therapy during the outbreak.9 Previous studies using the self-controlled case series method provided evidence that the outbreak may increase the risk of STEMI during the acute phase of infection.24 However, the reduced number of admissions during the outbreak is likely to have resulted in increases in out-of-hospital deaths and long-term complications.6 Our current study focuses on the postoutbreak time, with the advantage that data are prospectively collected and data validation is facilitated through monthly and quarterly data audit and feedback. A nationwide study in UK reported a 23% decrease in admissions for STEMI from 2019 to the end of March 2020, and admission rates for STEMI had partly recovered but remained about 16% below baseline levels by the end of May 2020.6 While a few studies indicated that there might be a post-COVID-19 rebound for STEMI admissions.13 Our current study adds the evidence from the low-income and middle-income countries, showing a 53% and 38% decline in STEMI admissions, respectively, comparing the outbreak and the corresponding period of 2019, and the postoutbreak and the corresponding period of 2019. Moreover, we find that the per cent of cases transferred by ambulance declined significantly from 9.3% to 4.2% in the postoutbreak time in comparison with the corresponding period of 2019. Causes for less presentation for healthcare are likely multifactorial and most researches emphasise that patients may be reluctant to present to hospitals because of the fear of contracting the coronavirus infection.6 25 Thus, the risk for patients failing to attend hospitals with STEMI would be lasted even after the wave of the COVID-19 outbreak, leading to unnecessary deaths and disability. This is particularly true for low-income and middle-income countries, where patients’ knowledge on STEMI and awareness of protection are relatively limited with the information of prevention of COVID-19 explosion. Educational outreach to community including STEMI awareness and COVID-19 knowledge is warranted. In China, hospitals are encouraged to establish a medical consortium of STEMI healthcare. Hospitals are partnered with community healthcare centres to form an information-sharing and resource-management model. Community healthcare workers conduct management of STEMI healthcare among community residents, which are part of the essential public health services in China. Thus, community-based education supervised by hospitals within a medical consortium should be established within routine services delivery, to inform the public that hospitals remain fully operational and have stringent infection-control protocols in place even in the postoutbreak time.

Obviously, national lockdowns and altered healthcare priorities in response to COVID-19 outbreak are affecting the diagnosis and treatment of STEMI. According to Consensus on Diagnosis and Treatment Processes of STEMI in the Context of Prevention and Control of COVID-19, patients excluded from COVID-19 should be transferred immediately to the cardiac catheterisation room for PCI therapy.26 For very few patients with suspected COVID-19, emergency intravenous thrombolysis is the first choice for cases with no contraindication to thrombolysis, which will not impact the proportion of PCI rate and affect the quality of medical care; If COVID-19 is excluded after intravenous thrombolysis, patients could be transferred to the cardiac care units. In the post-COVID-19 era, it is still recommended to follow the consensus. In fact, most hospitals do not have professional protected cardiac catheterisation rooms and cardiac care units for respiratory infectious diseases.27 Given the conflict between time required for coronavirus nucleic acid detection and early PCI for STEMI, thrombolysis is conducted in priority in the emergency room, and sample for the coronavirus nucleic acid detection is sent after the start of thrombolysis. Since the results of nucleic acid detection should be waited for several hours that must lead to delays in treatment, cardiologists can make the treatment decision after full consideration of the benefit to risk ratio; if the possibility of having COVID-19 based on the respiratory symptoms and epidemiological exposure history is clinically small, PCI can be conducted immediately in an isolation ward.28 In our study, all the patients enrolled were negative for COVID-19. We have analysed all the intervals of the treatment delay, including patient delay and system delay (including prehospital delay and in-hospital delay). Notably, the extension in patient delay showed no significant during the postoutbreak and the corresponding periods of 2018–2019. We observed a significant prolongation of the door-to-balloon time and the FMC-to-device time, mainly due to the requirement of testing negativity for coronavirus infection. Meanwhile, a 12-point percentage of decline in rate of PCI therapy was observed over the period of the postoutbreak and the corresponding periods in 2019. Thus, even in the post-COVID-19 era, delays in the in-hospital treatment may be prolonged because the emergency infection protocols could result in a hinder for timely PCI therapy.

Our findings also show that the in-hospital mortality increased from 2.1% to 6.0% between the outbreak and the corresponding period of 2019, and the in-hospital mortality declined from the outbreak to the postoutbreak time, but the change was not significant. There are several potential reasons for the persistent clinical outcome during the COVID-19 outbreak and the post-COVID-19 era. First is the characteristics of patients hospitalised with STEMI. Although clinical characteristics, vital signs and Killip class were fairly consistent across periods, patients in the postoutbreak time were about 5 years younger and had a 13-point lower percentage of female, comparing those in the outbreak time. Although the explication of reasons for these changes is beyond the scope of our study, a number of prior studies pointed out the fact that elderly and female patients with STEMI have higher in-hospital mortality or worse clinical outcomes than the young and the male.29 30 Nevertheless, data of our study provide additional information that neither the risk profile of patients hospitalised with STEMI has significantly changed in the postoutbreak time and nor have the clinical outcomes. Second is the treatment approaches for patients hospitalised with STEMI. The rates of PCI therapy persisted about 60% during the outbreak and the postoutbreak, lower than those in the corresponding periods of 2018–2019 at about 70%. The result is in line with a series of studies reporting a reduction in the PCI therapy as a result of the COVID-19 pandemic.1 31 32 These results were coupled with delays in the PCI therapy, pointing to the persistently high in-hospital mortality during the outbreak and the postoutbreak. Clinical outcome in patients with STEMI in the postoutbreak time might be influenced by the delay to treatment and less use of PCI therapy. Therefore, it is imperative to improve the healthcare delivery system’s ability to maintain healthcare coordination for timely PCI with respect to STEMI cases. Prior studies have shown that a dedicated coordinator from a medical consortium of STEMI healthcare could play a critical role in maintaining coordination of healthcare, in charge of coordination of community healthcare centres, hospitals and EMS agencies, and collaboration of multidisciplinary teams including the cardiology department, emergency department, infections department, pneumology department and the medical laboratory department.16 33

COVID-19 has influenced the treatment of STEMI patients from the organisational and management structure, such as reduced public willing, stricter community control, complicated medical referral process, occupation of ambulance infectious disease services and crowding of hospital medical resources. It is urgent for the medical Alliance to provide relevant treatment referral strategies to promote the implementation of local government. Advocacy is also needed to raise public awareness and further improve treatment.

Limitations

This study has several limitations. First, in a dynamic retrospective study, there would be concerns related to confounding, bias and temporal trends in quality of healthcare that might limit the validity of the findings. However, we compared the changes in the quality metrics of healthcare by comparison between the corresponding periods in 2020 and 2019, as well as those in 2019 and 2018. Our findings showed that most of the indicators got better or remained stable over the periods of 2018 and 2019, while got worse during 2019 and 2020. These results indicated that our study may merely underestimate the impact of the COVID-19 outbreak and the post COVID-19 era on quality of healthcare. Second, with one city selected in the sampling frame, the national representativeness of the study sample cannot be ascertained. However, the city of Suzhou is one of the first cities having responded to the national call for public health measures for combating the pandemic, and lead to develop chest pain centres accredited by National Health Commission to guide standardised prehospital and in-hospital STEMI healthcare in a regional level in China. Third, for PCI procedure, team coworking problem and a number of extra shifts in catheterisation lab, which may affect treatment time and quality of care were not considered in this study, due to the data availability. Future researches need to focus on the coordination of care and task shifts for STEMI patients in responses to the pandemic from the perspectives of quality of care. We believe that the selected sample is generally representative of the health and economic development in the most developed urban China.

Conclusions

It is key to note that the impact of public health restrictions in the post-COVID-19 era is significant, and may lead to unexpected out-of-hospital deaths and negatively influence quality of healthcare among patients with STEMI. Delay or absence in presentation in STEMI patients should be continuously considered avoiding the secondary disaster of the pandemic. System delay should be modifiable for reversing the worst clinical outcomes from the COVID-19 outbreak, by coordination measures with focus onh the balance between timely PCI procedure and minimising contamination of cardiac catheterisation rooms.

Data availability statement

Data may be obtained from a third party and are not publicly available. Data for this study were obtained from the China Chest Pain Center Database (http://data.chinacpc.org/), a nationwide clinical registry for collecting data of all consecutive patients diagnosed with STEMI enrolled by hospitals. The data management committee, one of the committees of the management board was responsible for evaluating and monitoring the Date.

Ethics statements

Patient consent for publication

Ethics approval

Ethics approvals of the study have been obtained from the Peking University Health Science Center Institutional Review Board (IRB00001052-21020). Participants gave informed consent to participate in the study before taking part.

References

Supplementary materials

  • Supplementary Data

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Footnotes

  • Contributors JM had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis; Design of the study: YJ and Z-JZ; Collection, analysis and interpretation of the data: YJ and JM; Preparation, review, or approval of the manuscript: YJ, Z-JZ, JM, MSLN, SZ, XD, MM and DY. We thank the Suzhou Emergency Center for providing the data and sharing comments for the study’s findings. YJ is responsible for the overall content as guarantor.

  • Funding This paper was supported by the National Natural Science Foundation of China (No. 71904004), and the 2020 China Medical Board (CMB) Open Competition Program (No. #20-376).

  • Disclaimer The study sponsor has no role in study design, data analysis and interpretation of data, the writing of manuscript, or the decision to submit the paper for publication.

  • Competing interests None declared.

  • Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.