International Journal of Cardiology 177 (2014) 494–496
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International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Letter to the Editor
Effects of new regional cooperative rescue model on patients with ST-elevation myocardial infarction Jinchuan Yan ⁎, Zhongqun Wang, Liang jie Xu, Yi Liang Department of Cardiology, Affiliated Hospital of Jiangsu University, Jiangsu 212001, China
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Article history: Received 10 August 2014 Accepted 11 August 2014 Available online 16 August 2014 Keywords: Acute myocardial infarction First medical contact Regional cooperative rescue model
Acute myocardial infarction (AMI) is one of the most serious diseases that affects the life and health of people, but b30% of all of the patients with AMI has been treated effectively and timely in China. Delayed treatment has been considered as a leading cause of death and severe outcomes. Current ESC Guidelines state that emergency percutaneous coronary intervention (PCI) should be performed in 120 min from the first medical contact. Hence, the original standard of door-to-balloon (D-to-B) time of b90 min has been changed to the first medical contact-to-balloon (FMC-to-B) time of b120 min [1,2]. This study aimed to determine whether or not a new regional cooperative emergency model (NRCEM) improves the FMC-to-B and the therapeutic effects on patients with ST-elevation myocardial infarction (STEMI). In this study, 1008 STEMI patients were recruited and treated with emergent PCI in our hospital from January 2008 to September 2013. The patients were divided into two groups in terms of whether or not a NRCEM was used: regional cooperative treatment group (n = 588) and control group (n = 420). The inclusion criteria included: (1) duration of typical chest pain lasted more than 30 min; (2) ST-segment elevation of either of the two adjacent prethoracic leads exceeds 0.1 mV and this elevation evolves dynamically; (3) patients within 24 h of paroxysm from other hospitals were transferred to our hospital and treated with emergent PCI; and (4) coronary angiography showed infarction-related arteries exhibiting total or subtotal occlusion. All of the patients were administered with oral load aspirin (0.3 g), Plavix (0.3 g) before the operation was performed. Emergency cardiac catheterization and PCI procedures were performed using standard
⁎ Corresponding author. Fax: +86 511 85026169. E-mail address:
[email protected] (J. Yan).
http://dx.doi.org/10.1016/j.ijcard.2014.08.074 0167-5273/© 2014 Elsevier Ireland Ltd. All rights reserved.
methods. After PCI was conducted, the patients were routinely treated with anticoagulant heparin and anti-platelet aspirin (0.1 g) and Plavix (75 mg). In the regional cooperative treatment group, patients initially consulted a physician in primary grade hospitals (such as rural/ community/county hospitals) with real-time 12-lead electrocardiogram (ECG) transmission equipment provided from the IVT Corporation. The principle of Holter was applied when the ECG data collection terminal was used, and collected ECG data were wirelessly transmitted to a tablet computer via a Bluetooth 3.0 communication protocol. The latter can display real-time 12-lead ECG. The working principle is similar to 12-lead monitors. The only difference is that the tablet computer could transmit ECG data in real-time by 3G networks to our cardiology center. The experts in our center can view real-time ECG by using any terminal equipment, such as a networking computer, or a 3G cell-phone. Once the diagnosis of STEMI was confirmed and transferred to our center, a cardiac catheterization team was activated immediately to facilitate preoperative preparation; an ambulance directly entered the PCI center. In the control group, patients who first visited rural/community hospitals were selected by ambulances or self-driving cars without electrocardiographic equipment were transported to the emergency center or out-patient department of our hospital, where the diagnosis of STEMI was performed and re-routed to the PCI center. To analyze this delay, we prospectively obtained the following time segments: FMC-to-B time, D-to-B time, transfer time, and informed consent time. To assess the treatment effect, we evaluated cardiac function (2 days, 1 month, and 6 months after PCI) and MACE in the six months after PCI. To analyze the economic benefits, we assessed mean cost and hospitalization days. Statistical analysis was performed with GraphPad software and SPSS11.5 software. P b 0.05 was considered statistically significant. The baseline characteristics of the two groups are listed in Table 1. Experimental group and control groups exhibited no significant differences in sex, age, lesion number, infarction area, and risk factors. The different time intervals in each group are summarized in Table 2. The control group showed a greater delay in informed consent and transfer time whereas the experimental group exhibited shorter total time because of a pre-hospital delay. Moreover, FMC-to-B time and D-to-B time were significantly decreased. We also found that LVEF at 2 days, 1 month and 6 months after PCI was increased, but LVED was deceased in experiment group compared with the corresponding index in the control group (Table 3).
J. Yan et al. / International Journal of Cardiology 177 (2014) 494–496 Table 1 Baseline characteristics of the patients.
Men/women Age (years) Vascular lesions (single/multi branch) Anterior MI Non anterior MI Hypertension Hypercholesterolemia Smoker Diabetes
Experiment group (n = 588)
Control group (n = 420)
383/205 59.8 ± 8.5 207/381 351 (59.7%) 237 (40.3%) 214 (36.4%) 219 (37.3%) 306 (52.2%) 181 (30.9%)
274/146 60.2 ± 8.7 147/273 243 (57.9%) 177 (42.1%) 152 (36.2%) 157 (37.5%) 220 (52.4%) 168 (40%)
MI: myocardial infarction.
Table 2 Times and delays of the patients (min, x ± s). Number FMC-to-B time Experiment 588 group Control group 420 P value a
D-to-B time
97 ± 17 209 ± 32 0.02
Transfer time
24 ± 5 a
103 ± 16 0.001
Informed consent time
60 ± 13 a
101 ± 17 0.001
8±5 a
25 ± 8a 0.002
P b 0.05 compared with the control group.
The patients in the two groups were followed up 6 months after PCI. The MACE of experimental group was 7.3%; mortality was observed in 10 cases (1.7%), recurrent angina was found in 25 cases (4.3%), and recurrent myocardial infarction was detected in 8 cases (1.3%). The MACE of the control group was 17.9%; mortality was observed in 15 cases (3.6%), recurrent angina was detected in 37 cases (8.9%), revascularization was found in 13 cases (3%), and recurrent myocardial infarction was recorded in 10 cases (2.4%). The MACE rate of the experimental group was significantly lower than that in the control group. The mean hospitalization days of the experimental group and the control group were 7.62 and 11.63 days. The median of the experimental group was 7 days, which decreased 3 days compared with that of the control group. We used the Wilcoxon test to analyze the hospitalization of the two groups. Our results showed that the difference was statistically significant (Z = −12.03, P b 0.05). The mean cost of the experimental group was 44,526.0 CNY, whereas that of the control group was 52,863.0 CNY. Moreover, the median of the experimental group was 42,221.0 CNY, which decreased 7433.0 CNY compared with that of the control group. Our results showed that the difference was statistically significant (Z = −4.05, P b 0.05). The first few hours are necessary to limit infarction size and prevent cardiac death in patients with AMI. Thus, the delay from the time when the patient seeks medical care to the time of the opening of culprit vessel is a crucial factor to determine the efficacy of the procedure and the results [3]. Foreign studies have showed that the delay time from symptom onset to the first day of treatment of patients with AMI is approximately 6 h [4–7]; the delay time for patients in China may be longer than 6 h. The D-to-B time in America is approximately 95 min. The study of CREST-MI from Beijing Chaoyang Hospital showed that the D-to-B time in China is about 119 min and exceeds the recommended time stated in guidelines. This drawback could be resolved by building a chest pain center in a large city; with this healthcare facility, D-to-B time
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could be shortened to 90 min. However, construction of healthcare facility in small- and medium-sized cities is difficult; likewise, construction of such facilities is complicated in rural areas. This study aimed to establish a NRCEM for STEMI patients with high efficiency, easy reproducibility, and dissemination to facilitate the implementation of multiple clinical practice guidelines based on modern network information technology. This model involves information technology, management science, and medicine. Using this model, specialists in our hospital can guide the first remote-site medical aid to elevate the success rate of rescues and promote professional technology in rural/community hospitals. On the basis of real-time life-monitoring remote transmission system, we established an integrative system of heart attack risk assessment, early screening, pre-hospital and in-hospital care, and CCU treatment. We also established remote CCU and mobile CCU based on a network with rural/community hospitals; thus, the information of patients with AMI in rural/community hospital can be transmitted to our cardiology center. NRCEM was defined to provide continuous emergency cardiovascular care for anyone, anywhere, and anytime by regional cooperative healthcare. Using this model, we could timely diagnose patients with AMI, monitor in real time, and treat patients even at a long distance. Furthermore, once a patient enters an ambulance, preoperative preparation is activated. Consequently, unnecessary time delays are avoided, thereby decreasing medical costs, and improving treatment efficiency and clinical prognosis. On the basis of this theory, we recruited 1008 patients with AMI. The NRCEM was used for 588 patients and the conventional referral model was used for the other patients. The pre-hospital delay, FMC-B time, D-to-B time, and total time of the experimental group were significantly shortened compared with the corresponding indexes of the control group. Furthermore, LVEF was increased and LVED was deceased in the experimental group. The results also showed that the NRCEM could significantly decrease mean costs, days of hospitalization, and reduce the time of diagnosis and treatment. The incidence rate of MACE in the experimental group was 7.3%, the rate in the control group was 17.9%. These data showed that the regional cooperative rescue model is an effective basis of AMI treatment. Although project-clinical pathways were established for acute coronary artery syndrome-3 in second-class hospitals in our country in July 2011, the application of AMI clinical pathway is not optimistic. At present, many patients with AMI initially visited rural/community hospitals, where diagnosis, treatment guidelines, and rescue process are difficult to implement. Thus, culprit artery is difficult to open and reperfusion is hard to implement immediately. For this reason, regional cooperative rescue model, a new AMI emergency system in China, should be established as an available method to treat AMI in the future.
Conflict of interest There was not any potential conflict of interest for all authors.
Acknowledgments This work was supported by the National Natural Science Foundation of China (81170279, 81370409), the Health Department of Jiangsu
Table 3 Cardiac function of the patients (x ± s). Number
Experimental group Control group P value
588 420
LVEF (%)
LVED (mm)
2 days
1 month
6 months
2 days
1 month
6 months
49.4 ± 7.3 47.7 ± 8.4 0.01
54.2 ± 7.4 48.6 ± 9.2 0.01
54.9 ± 8.6 48.9 ± 9.1 0.01
49.7 ± 6.5 51.7 ± 6.3 0.047
49.2 ± 7.0 51.4 ± 5.3 0.021
48.9 ± 5.7 51.4 ± 6.0 0.005
LVEF: left ventricular ejection fraction; LVED: left ventricular end diastolic.
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