The burden of acute myocardial infarction after a regional cardiovascular center project in Korea

Real-World Long-Term Clinical Outcomes of Ultrathin Strut Biodegradable Polymer Drug-Eluting Stents in Korean ST-Segment-Elevation Myocardial Infarction (STEMI) Patients with or without Acute Heart Failure Undergoing Primary Percutaneous Coronary Intervention

Biodegradable polymers (BDPs) and ultrathin struts were recently introduced to drug-eluting stents (DES) to further improve outcomes. In this study, we analyzed and compared the effect of the ultrathin strut BDP-DES (UBDP-DES) with the conventional durable polymer-DES (DP-DES) in patients with ST-segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PPCI). A total of 356 STEMI patients (n = 160 in the UBDP-DES group and n = 196 in the DP-DES group) were enrolled. The primary endpoint was target lesion failure (TLF), including cardiac death, target vessel myocardial infarction, and ischemic-driven, target lesion revascularization (ID-TLR). The mean age was 60.3 ± 12.7 years (male 81.7%), and the median follow-up duration was 63.8 months. TLF was numerically more frequent in the UBDP-DES group (8.1% vs. 4.1%; HR 2.14; 95% CI 0.89-5.18; p = 0.091). Propensity score matching (PSM) was performed to balance discrepancies in the baseline characteristics due to patients in the UBDP-DES group initially having more unstable vital signs. However, after PSM (n = 116 in each group), there was no significant difference in TLF (5.3% vs. 5.3%; HR 1.04, 95% CI 0.34-3.22; p = 0.947) or other secondary endpoints including ID-TLR. In the subgroup analysis, subjects with initial acute heart failure (AHF), defined as Killip class ≥ 3, were associated with 13.6% chance of 30-day mortality (9-fold of those without AHF), although chances of repeat revascularization were low (3.0%). Among patients with AHF, the UBDP-DES group was associated with a numerically higher chance of TLF compared with the DP-DES group. There was no difference in TLF between groups in patients without AHF. This study showed that UBDP-DES has long-term clinical outcomes similar to those of conventional DP-DES in real-world Korean STEMI patients receiving PPCI, especially in those without initial AHF.

Current Status of Cardiac Rehabilitation in the Regional Cardiocerebrovascular Centers in Korea

Regional Cardiocerebrovascular Centers (RCCs)—a Korean government initiative—seek to reduce medical gaps across regions, and their cardiac rehabilitation (CR) programs are expected to model post-acute care for the Korean CR program. Accordingly, this study aimed to evaluate the current status of CR programs in the RCCs. We distributed surveys on the CR condition, activity, and barriers to 12 RCCs in different provinces. The results revealed significant gaps in the annual number of acute myocardial infarction admissions, and CR candidates, capacity, and density across the 12 RCCs. The CR capacity (50–500) and density (0.42–7.36) indicated particularly large gaps. Twelve RCCs had the necessary facilities, equipment and personnel for CR assessments and management, with high CR referral (97%) and patient education (78%) rates. However, the inpatient CR exercise training (56%) participation rate was inadequate, with much lower enrollment (47%) and adherence (17%) rates to the outpatient CR program and large differences across centers. Therefore, this study’s results will provide the evidence required to establish special national health strategies to overcome the CR barriers of patient, doctor/hospital, and policy factors for activating Korean CR programs.

mHealth Interventions for Lifestyle and Risk Factor Modification in Coronary Heart Disease: Randomized Controlled Trial

Background

Self-management of lifestyle and cardiovascular disease risk factors is challenging in older patients with coronary heart disease (CHD). SMS text messaging could be a potential support tool for self-management and the most affordable and accessible method through a mobile phone. High-quality evidence had been lacking, and previous studies evaluated the effects of SMS text messaging on the subjective measures of short-term outcomes. Recently, a large-sized randomized controlled trial in Australia reported promising findings on the objective measures upon 6-month follow-up. However, an examination of the effectiveness of such interventions in an Asian population with unique demographic characteristics would be worthwhile.

Objective

This study examined the effectiveness of a 1-way SMS text messaging program to modify the lifestyle and cardiovascular disease risk factors of patients who underwent the first percutaneous coronary intervention (PCI).

Methods

A parallel, single-blinded, 1:1 random allocation clinical trial was conducted with 879 patients treated through PCI. They were recruited during hospital admission from April 2017 to May 2020 at 2 university hospitals in the Republic of Korea. In addition to standard care, the intervention group received access to a supporting website and 4 SMS text messages per week for 6 months regarding a healthy diet, physical activity, smoking cessation, and cardiovascular health. Random allocation upon study enrollment and SMS text messaging after hospital discharge were performed automatically using a computer program. The coprimary outcomes were low-density-lipoprotein cholesterol (LDL-C), systolic blood pressure (SBP), and BMI. The secondary outcomes were change in lifestyle and adherence to the recommended health behaviors.

Results

Of the eligible population, 440 and 439 patients who underwent PCI were assigned to the intervention and control groups, respectively. The 1-way SMS text messaging program significantly enhanced physical activity (P=.02), healthy diet (P<.01), and medication adherence (P<.04) among patients with CHD. Hence, more people were likely to control their cardiovascular disease risk factors per the recommendations. The intervention group was more likely to control all 5 risk factors by 62% (relative risk 1.62, 95% CI 1.05-2.50) per the recommendations. On the other hand, physiological measures of the primary outcomes, including LDL-C levels, SBP, and BMI, were not significant. Most participants found the SMS text messaging program useful and helpful in motivating lifestyle changes.

Conclusions

Lifestyle-focused SMS text messages were effective in the self-management of a healthy diet, exercise, and medication adherence, but their influence on the physiological measures was not significant. One-way SMS text messages can be used as an affordable adjuvant method for lifestyle modification to help prevent the recurrence of cardiovascular disease.

Trial Registration

Clinical Research Information Service (CRiS) KCT0005087; https://cris.nih.go.kr/cris/search/detailSearch.do/19282

Did inter-hospital transfer reduce mortality in patients with acute myocardial infarction in the real world? A nationwide patient cohort study

INTRODUCTION

Inter-hospital transfer (IHT) and primary percutaneous coronary intervention (PCI) are preferred over onsite thrombolysis when provided expeditiously. On the other hand, its benefit has not been evaluated in a real-world situation. This study examined the effects of IHT on the short- and long-term mortality in patients with acute myocardial infarction (AMI) and compared the reperfusion treatments and resources between the referring and receiving hospitals.

METHODS

Patients newly diagnosed with AMI and admitted to hospital were selected from the national health insurance database from 2004 to 2018. The 30-day and one-year mortality in the transferred and non-transferred patients were estimated and compared using stabilized inverse probability of treatment weighting to account for confounding bias.

RESULTS

Of the 258,291 participants, 10,158 were transferred to one or more hospitals. IHT was more likely to occur to older or more comorbid people, patients in rural areas, and those whose insurance was medical aid. The 30-day and one-year mortality of the non-IHT group was 9.7% and 15.8%, respectively, whereas the figure was 11.4% and 20.5% in the IHT group. After balancing the baseline characteristics, the transferred patients were 1.12 (95% CI: 1.06-1.20) and 1.25 (95% CI: 1.20-1.31) times more likely to die during the subsequent 30 days and one year, respectively, than those treated solely at the presenting hospital. In ST-segment elevation myocardial infarction (STEMI), the hazard ratios of the 30-day and 1-year mortality were 1.14 (95% CI: 0.97-1.35) and 1.31 (95% CI: 1.15-1.49) in the transferred patients after balancing cardiogenic shock and cardiac arrest. On-site thrombolysis was rarely performed in the referring hospitals.

CONCLUSION

Patients transferred for the treatment of AMI experienced higher short- and long-term mortality. Therefore, onsite thrombolysis and the estimated time delay to PCI should be considered in regional hospitals to reduce mortality with the organization of STEMI treatment networks.

Machine learning enhances the performance of short and long-term mortality prediction model in non-ST-segment elevation myocardial infarction

Machine learning (ML) has been suggested to improve the performance of prediction models. Nevertheless, research on predicting the risk in patients with acute myocardial infarction (AMI) has been limited and showed inconsistency in the performance of ML models versus traditional models (TMs). This study developed ML-based models (logistic regression with regularization, random forest, support vector machine, and extreme gradient boosting) and compared their performance in predicting the short- and long-term mortality of patients with AMI with those of TMs with comparable predictors. The endpoints were the in-hospital mortality of 14,183 participants and the three- and 12-month mortality in patients who survived at discharge. The performance of the ML models in predicting the mortality of patients with an ST-segment elevation myocardial infarction (STEMI) was comparable to the TMs. In contrast, the areas under the curves (AUC) of the ML models for non-STEMI (NSTEMI) in predicting the in-hospital, 3-month, and 12-month mortality were 0.889, 0.849, and 0.860, respectively, which were superior to the TMs, which had corresponding AUCs of 0.873, 0.795, and 0.808. Overall, the performance of the predictive model could be improved, particularly for long-term mortality in NSTEMI, from the ML algorithm rather than using more clinical predictors.

Implementation of National Health Policy for the Prevention and Control of Cardiovascular Disease in South Korea: Regional-Local Cardio-Cerebrovascular Center and Nationwide Registry

Cardiovascular disease (CVD) remains the leading cause of morbidity, mortality, and health care costs in South Korea. The prevalence of preventable and treatable risk factors for CVD such as obesity, hypercholesterolemia, and smoking has continued to increase, despite improvements management of hypertension. Active leadership, participation, and support of professional organizations and medical institutions in national cardiovascular registries and regional treatment network have proven to be effective models to reduce the global burden of CVD in the Europe and North America. Regional treatment network systems for ST-segment elevation myocardial infarction have established to coordinate percutaneous coronary intervention (PCI) treatment centers, non-PCI treatment centers, and emergency centers especially across the Europe. The Act on the Prevention and Management of Cardio-cerebrovascular Disease was enacted in South Korea in 2017 to establish the legal frameworks and a comprehensive plan for the prevention and management CVD and risk factors. To fully achieve the goal of a National Health Plan for Cardiovascular Disease, it is necessary to embark on a nationwide registry project and to promote the regional acute treatment accessibility which can therefore play a key role in achieving the objectives of the 2017 Act. In this regard, the Korean Society of Cardiology advocates a national project for health promotion and cardiovascular prevention to improve cardiovascular outcomes, which includes the expansion and establishment of regional cardio-cerebrovascular centers (CCVCs) and new local CCVCs.

Association between health insurance status and transfer of patients with return of spontaneous circulation after out-of-hospital cardiac arrest

AIM

To explore the factors related to the probability of inter-hospital transfer to a heart attack centre in patients with return of spontaneous circulation after out-of-hospital cardiac arrest (OHCA) in the Republic of Korea.

METHODS

This cross-sectional observational study used data from a Korean national emergency medical service OHCA database for cases between 2015 and 2017. Adult OHCA patients with a presumed cardiac origin who initially presented at a non-heart-attack centre were included in the analysis. The main exposure variable was health insurance type (national health insurance versus medical aid), which was used as a proxy measure of individual socioeconomic status. The primary outcome was emergency department disposition (transfer to a heart attack centre versus no transfer). A multivariate logistic analysis using propensity score matching was conducted. We also analysed the associations between patient transfer and neurologic recovery as well as survival to discharge.

RESULTS

Of 7804 eligible OHCA patients, 1804 23.0%) were transferred to a heart attack centre. Patients on medical aid were less likely to be transferred (adjusted odds ratio [OR], 0.75; 95% confidence interval [CI], 0.59-0.95 in a matched cohort) compared with patients with national health insurance. Transfer to a heart attack centre was significantly associated with a lower risk of death (adjusted OR, 0.38; 95% CI, 0.33-0.45) and better neurologic recovery (adjusted OR, 0.46; 95% CI, 0.38-0.56).

CONCLUSION

Socioeconomic status appears likely to influence the probability of transfer to a heart attack centre after resuscitation.

Estimating the Economic Burden of Acute Myocardial Infarction in the US: 12 Year National Data

BACKGROUND

Acute myocardial infarction (AMI) carries a substantial mortality and morbidity burden. The purpose of this study is to provide annual mean cost per patient and national level estimates of direct and indirect costs (lost productivity from morbidity and premature mortality) associated with AMI.

METHODS

Nationally representative data spanning 12 years (2003-2014) with a sample of 324,869 patients with AMI from the Medical Expenditure Panel Survey (MEPS) were analyzed. A novel 2-part model was used to examine the excess direct cost associated with AMI, controlling for covariates. To estimate lost productivity from morbidity, an adjusted Generalized Linear Model was used for the differential in wage earnings between participants with and without AMI. Lost productivity from premature mortality was estimated based on published data.

RESULTS

The total annual cost of AMI in 2016 dollars was estimated to be $84.9 billion, including $29.8 billion in excess direct medical expenditures, $14.6 billion in lost productivity from morbidity and $40.5 billion in lost productivity from premature mortality between 2003 and 2014. In the adjusted regression, the overall excess direct medical expenditure of AMI was $7,076 (95% confidence interval [CI] $6,028-$8,125) higher than those without AMI. After adjustment, annual wages for patients with AMI were $10,166 (95% CI -$12,985 to -$7,347) lower and annual missed work days were 5.9 days (95% CI 3.57-8.27) higher than those without AMI.

CONCLUSIONS

The study finds that the economic burden of AMI is substantial, for which effective prevention could result in significant health and productivity cost savings.

Are PCI Service Volumes Associated with 30-Day Mortality? A Population-Based Study from Taiwan

The volume-outcome relationship has been discussed for over 30 years; however, the findings are inconsistent. This might be due to the heterogeneity of service volume definitions and categorization methods. This study takes percutaneous coronary intervention (PCI) as an example to examine whether the service volume was associated with PCI 30-day mortality, given different service volume definitions and categorization methods. A population-based, cross-sectional multilevel study was conducted. Two definitions of physician and hospital volume were used: (1) the cumulative PCI volume in a previous year before each PCI; (2) the cumulative PCI volume within the study period. The volume was further treated in three ways: (1) a categorical variable based on the American Heart Association’s recommendation; (2) a semi-data-driven categorical variable based on k-means clustering algorithm; and (3) a data-driven categorical variable based on the Generalized Additive Model. The results showed that, after adjusting the patient-, physician-, and hospital-level covariates, physician volume was associated inversely with PCI 30-day mortality, but hospital volume was not, no matter which definitions and categorization methods of service volume were applied. Physician volume is negatively associated with PCI 30-day mortality, but the results might vary because of definition and categorization method.

The influence of emergency department crowding on the efficiency of care for acute stroke patients

Objective

To investigate the impact of emergency department (ED) crowding (number of ED patients) and number of ED staff on the efficiency of the ED care process for acute stroke patients.

Design

Retrospective cohort study conducted from 1 May 2008 to 31 December 2013.

Setting

Largest primary stroke center (3000-bed tertiary academic hospital) in southern Taiwan.

Participants

Patients aged 18-80 years presenting to the ED with acute stroke symptoms ≤3 h from symptom onset (n = 1142).

Main Outcome Measures

Door-to-assessment time (DTA), door-to-computed tomography completion time (DTCT) and door-to-needle time (DTN).

Results

Of the 785 patients with ischemic stroke, 90 (11.46%) received thrombolysis. In the multivariate regression analysis, the number of ED patients and the number of attending physicians were significantly associated with delayed DTA and DTCT but not DTN. Initial assessment by a resident was also associated with delayed DTA and DTCT. The number of nurses was associated with delayed DTCT and DTN.

Conclusions

Although ED crowding was not associated with delayed DTN, it predicted delayed DTA and DTCT in thrombolysis-eligible stroke patients. The number of attending physicians affected initial assessment and DTCTs, whereas the number of nurses impacted thrombolytic administration times.

Metafrontier frameworks for studying hospital productivity growth and quality changes

Objective

The objective of this study was to evaluate productivity growth and quality changes among different levels of accredited hospitals.

Design

This study used an attribute-incorporating Malmquist productivity index (MPI) under the metafrontier framework. This is the first attempt to compare productivity changes among hospitals operating under different production frontiers.

Participants

The data consisted of 20 academic medical centers (AMCs), 61 metropolitan hospitals (MPs) and 112 local community hospitals (LCs) in Taiwan during the period 2007-2010.

Main outcome measures

This study measured productivity growth and further identified technological gaps and catch-ups in different groups of hospitals with respect to the metafrontier. At the same time, comparisons of changes in quality among different levels of hospitals were also examined.

Results

We found that the sample hospitals of AMCs and MPs experienced productivity improvements mainly due to technological progress, but their efficiency and technology gap ratio (TGR) deteriorated. As for LCs, progress in technology along with improvements in their efficiency and TGR led to the highest productivity upgrade among the three groups of hospitals. We also found that the sample hospitals among the three groups showed improvements in quality. Moreover, hospitals in the local community group exhibited greater quality progress than the AMCs and MPs over the sample period.

Conclusion

This paper presents a number of useful decompositions of the metafrontier MPI, which can provide useful insights into changes that are due to efficiency, quality improvements and/or technological changes in the healthcare sector.