Impact of Implementation of a Region-Wide Low-Density Lipoprotein Cholesterol Management Clinical Pathway for the Secondary Prevention of Acute Myocardial Infarction

Abstract

Background: Aggressive lipid-lowering therapy is important for secondary prevention of acute myocardial infarction (AMI). The recommended target for low-density lipoprotein cholesterol (LDL-C) of <70 mg/dL is often not achieved. To address this gap, we implemented a clinical pathway in all hospitals that perform percutaneous coronary interventions (PCI) with primary care physicians in Nagasaki and aimed to validate the effectiveness of this pathway in an acute setting.

Methods and Results: This retrospective cohort study included medical records extracted from 8 hospitals in Nagasaki, Japan, where PCI was performed for patients with AMI. The index date was defined as the date of hospitalization for AMI between July 1, 2021, and February 28, 2023. The primary outcome was the rate of achieving LDL-C <70 mg/dL at discharge. The median baseline LDL-C level at admission was 121 mg/dL (n=226) in the pre-implementation group and 116 mg/dL (n=163) in the post-implementation group. In the post-implementation group, 131 patients were treated using the clinical pathway. The rate of achieving LDL-C <70 mg/dL at discharge increased significantly from 37.2% before implementation to 54.6% after implementation. Logistic regression analysis revealed a positive correlation between the implementation of the clinical pathway and achieving LDL-C <70 mg/dL.

Conclusions: Implementation of a region-wide clinical pathway for LDL-C management significantly improved the rate of intensive lipid-lowering therapy and the achievement of LDL-C targets.

Acute coronary syndrome (ACS) is caused by plaque rupture and thrombus occlusion in the coronary arteries.¹ Low-density lipoprotein cholesterol (LDL-C) is associated with vulnerable plaques, and lipid-lowering therapy suppresses cardiovascular events and induces plaque regression.^2–5 Given the high risk of recurrent cardiovascular events in patients with a history of ACS, aggressive lipid-lowering therapy is particularly desirable for secondary prevention.^6,7

Therefore, Japanese guidelines recommend the use of high-intensity statins from the acute phase for secondary prevention in patients with ACS with a target LDL-C level of <70 mg/dL.^8,9 If LDL-C levels cannot be lowered to <70 mg/dL, the addition of ezetimibe or proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors is recommended.^8,9 However, in clinical practice, the implementation rate of high-intensity statin therapy at the time of discharge varies widely,¹⁰ and the rate of achievement of LDL-C <70 mg/dL has been reported to be as low as 30%.¹¹ This highlights the problem of not providing adequate lipid-lowering therapy to patients with ACS from the acute phase.

Barriers in the clinical setting, such as inadequate discharge prescription, lack of medical collaboration, and poor patient adherence, contribute to this situation.¹² To improve the rate of achieving LDL-C <70 mg/dL in inpatients with ACS, the effectiveness of a hospital-based protocol focused on lipid-lowering therapy has been reported.¹³ Following the introduction of this protocol, the rate of achieving LDL-C <70 mg/dL improved from 27% to 58% at 12 months.¹³ However, that report is from a single center, and there have been no reports to date of the implementation and operation of a common protocol at multiple institutions in a region, and verification of the protocol’s effectiveness.

In Nagasaki City, a council of all hospitals performing percutaneous coronary intervention (PCI) and general physicians was formed, and an initiative to manage LDL-C using a region-wide clinical pathway (Nagasaki AMI Secondary Prevention Clinical Pathway) was initiated in July 2022. The present study examines the effectiveness of the Nagasaki AMI Secondary Prevention Clinical Pathway in acute care hospitals.

Methods

Study Design

We conducted a retrospective cohort study using medical records extracted from 8 hospitals in Nagasaki City, Japan, where PCI was performed for patients with acute myocardial infarction (AMI). The medical records of patients with AMI were extracted using electronic case reports. Patients admitted with AMI between July 1, 2021, and February 28, 2023, were included in the study. Patients were divided into pre- and post-implementation groups based on implementation of the clinical pathway in July 2022. However, at Nagasaki University Hospital, which had already implemented an in-hospital protocol similar to the clinical pathway before this study, patients were enrolled from July 1, 2017, to June 30, 2019, for a comparison of outcomes before and after protocol implementation. These patients were divided into pre- and post-protocol implementation groups, based on the implementation of the clinical pathway on July 1, 2018. Data were collected upon admission and at discharge.

This study was reviewed and approved by the Ethics Committee of Nagasaki University Hospital and was conducted in accordance with the ethical principles in the Declaration of Helsinki. Obtaining informed consent from patients was not applicable, and an opt-out approach was adopted, whereby public disclosure of the study content to the patients provided them the opportunity to request exclusion from the study.

Nagasaki AMI Secondary Prevention Clinical Pathway

Details of the Nagasaki AMI Secondary Prevention Clinical Pathway are shown in Figure 1. In the hospital phase, 1 of the 3 statins (atorvastatin 20 mg, rosuvastatin 10 mg, or pitavastatin 4 mg) was initiated as intensive statin therapy at the date of admission. One week after admission, LDL-C was measured, and 10 mg ezetimibe was added if the LDL-C level had not reached <70 mg/dL. LDL-C was measured again before discharge; if LDL-C was not <70 mg/dL, this was followed by consideration of atorvastatin or rosuvastatin, which were uptitrated to 40 or 20 mg, respectively, or the initiation of a new medication, a PCSK9 inhibitor, after discharge.

Figure 1.

Nagasaki AMI Secondary Prevention Clinical Pathway. AMI, acute myocardial infarction; FH, familial hypercholesterolemia; LDL-C, low-density lipoprotein cholesterol; PCSK9, proprotein convertase subtilisin/kexin type 9.

Patient Selection

Patients were included in the study based on the following criteria: hospitalized due to AMI between July 1, 2017, and February 28, 2023; diagnosed with AMI based on the universal definition of AMI;¹⁴ and age ≥18 years. Patients with myocardial infarction (MI) due to ischemic imbalance (e.g., coronary artery spasm, coronary embolism, tachycardia/bradycardia, anemia, respiratory failure, or hypotension) and procedure-related MI were not included in this study.

Outcomes

The primary outcome was the rate of achievement of LDL-C <70 mg/dL at discharge. In addition, the rate of achieving LDL-C <70 mg/dL at 4 weeks after discharge, the rate of achieving LDL-C <55 mg/dL at discharge, and changes in lipid-lowering therapy before and after implementation were evaluated. Hypertension was defined as blood pressure >140/90 mmHg in repeated measurements or the current use of antihypertensive medications. Dyslipidemia was defined as documented hyperlipidemia or the use of lipid-lowering medications. Diabetes was defined as HbA1c >6.5% or the use of antihyperglycemic medications.

Sample Size and Statistical Analysis

For the primary endpoint, the rate of achieving target LDL-C (<70 mg/dL) before implementation of the in-hospital clinical pathway was estimated to be 40% based on the report of preliminary research at Nagasaki University Hospital (44%), EXPLORE-J (34%),⁶ and the study of Nakao et al. (27%).¹³ The rate of achieving target LDL-C after implementation of the in-hospital clinical pathway was 85% at discharge in a preliminary study by Nagasaki University Hospital and 58% at 12 months after discharge in the study of Nakao et al.¹³ Based on these values, in the present study we estimated that the rate of achieving target LDL-C at discharge was 70%. Ninety-eight subjects were required to detect a 30% difference in the achievement rate before and after implementation of the in-hospital clinical pathway, with a 2-sided α of 0.05, a power of 80%, and a minimum sample size of 98 participants in both arms. Because the number of emergency PCI cases for AMI in Nagasaki City is approximately 250 per year and all patients extracted from the database were to be included in the analysis, the target number of patients to be analyzed was set at 400, comprising 250 and 150 patients in the pre- and post-implementation groups, respectively. Although the minimum sample size was calculated at a ratio of 1 : 1, the data collection period was different before and after the implementation of the clinical pathway; therefore, the target sample size was expected to be larger before implementation of the clinical pathway.

Clinically relevant risk-adjusted variables were selected based on previous reports and clinical relevance. Then, multivariable logistic regression analysis was performed by selecting variables that were significant at the 15% level in univariate logistic regression analysis.

For the primary endpoint, Fisher’s exact test (2 groups, unpaired) was used to compare the rate of achieving target LDL-C levels before and after implementation of the in-hospital clinical pathway. Continuous variables are expressed as the median with interquartile range (IQR). P<0.05 was considered statistically significant. All statistical analyses were performed using JMP version 17.0.0 (SAS Institute Inc., Cary, NC, USA).

Results

Patient Flow Chart

In all, 298 and 208 patients were enrolled in the pre- and post-implementation groups, respectively (Figure 2). After excluding patients for whom LDL-C at discharge was unavailable due to in-hospital death, transfer to other departments, or other reasons, the analysis included 226 patients in the pre-implementation group and 163 patients in the post-implementation group. Seventy-two patients were excluded in the pre-implementation group (21 in-hospital deaths, 9 transfers, and 42 others/unknown) and 45 were excluded in the post-implementation group (20 in-hospital deaths, 4 transfers, and 21 others/unknown).

Figure 2.

Patient flow chart. A total of 298 patients in the pre-implementation group and 208 patients in the post-implementation group were enrolled in this study. The analysis included 226 patients in the pre-implementation group and 163 in the post-implementation group, excluding those for whom low-density lipoprotein cholesterol (LDL-C) values at discharge were not available. AMI, acute myocardial infarction.

Baseline Patient Characteristics

Patient characteristics are presented in Table 1. The median age of the patients was 71 years (IQR 62–79 years), and 293 (75.3%) were male. Significantly fewer patients in the pre-implementation group required hemodialysis than in the post-implementation group. Other characteristics were not significantly different between the 2 groups.

Table 1.

Baseline Patient Characteristics

	Overall	Pre-implementation group	Post-implementation group	P value
No. patients	389	226	163
Male sex	293 (75.3)	171 (75.7)	122 (74.9)	0.8537
Age (years)	71 [62–79]	71 [62–79]	69 [61–79]	0.3368
≥75 years	133 (34.2)	82 (36.3)	51 (31.3)	0.3055
BMI (kg/m2)	23.1 [21.0–25.3]	23.2 [21.0–25.5]	22.8 [21.0–25.1]	0.4603
Hypertension	303 (77.9)	174 (77)	129 (79.1)	0.6141
Diabetes	161 (41.4)	93 (41.2)	68 (41.7)	0.9107
Dyslipidemia	302 (77.6)	175 (77.4)	127 (77.9)	0.9107
Smoking	220 (59.4)	128 (59.8)	92 (59)	0.8711
Hemodialysis	13 (3.3)	4 (1.8)	9 (5.5)	0.0422
Peripheral artery disease	9 (2.3)	5 (2.2)	4 (2.5)	0.8757
Cerebrovascular disease	37 (9.5)	22 (9.7)	15 (9.2)	0.8599
Ischemic heart disease	39 (10)	23 (10.2)	16 (9.8)	0.9069
Previous history of OMI	29	17	12
Previous history of PCI	37	22	15
Previous history of CABG	1	1	0
STEMI	308 (79.4)	175 (77.4)	133 (82.1)	0.2627
Length of stay (days)	13 [11–18]	13 [11–18]	13 [10–18]	0.623
Lipid profile at admission
LDL-C (mg/dL)	119 [95–147]	121 [97.25–148.75]	116 [93.5–145.5]	0.3476
HDL-C (mg/dL)	49 [41–60]	49 [40–61]	51 [41.5–59.5]	0.4556
Triglyceride (mg/dL)	116 [78–179]	111 [77.5–183.5]	118 [80–169.75]	0.9441
LDL-C categories				0.7194
<100 mg/dL	110 (28.3)	59 (26.1)	51 (31.3)
100–139 mg/dL	151 (38.8)	90 (39.8)	61 (37.4)
140–179 mg/dL	91 (23.4)	57 (25.2)	34 (20.9)
≥180 mg/dL	33 (8.5)	18 (8)	15 (9.2)
Unknown	4 (1.0)	2 (0.9)	2 (1.2)
Lipid-lowering therapy before admission
Statin	104 (27.5)	58 (26.4)	46 (29.1)	0.5548
Intensive statin	5 (1.3)	2 (0.9)	3 (1.9)	0.4062
Ezetimibe	17 (4.5)	10 (4.6)	7 (4.4)	0.9575
Fibrate	5 (1.3)	3 (1.4)	2 (1.3)	0.9346
Eicosapentaenoic acid	7 (1.9)	4 (1.8)	3 (1.9)	0.9543
PCSK9 inhibitor	0 (0)	0 (0)	0 (0)	N/A
Clinical pathway adopted	N/A	N/A	131 (80.4)	N/A

Unless indicated otherwise, data are presented as the median [interquartile range] or number of patients (%). BMI, body mass index; CABG, coronary artery bypass grafting; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; OMI, old myocardial infarction; PCI, percutaneous coronary intervention; PCSK9, proprotein convertase subtilisin/kexin type 9; STEMI, ST-elevation myocardial infarction.

Improvement in LDL-C Following Implementation of the Clinical Pathway

The median baseline LDL-C at admission was 121 and 116 mg/dL in the pre- and post-implementation groups, respectively. The rate of achieving LDL-C <70 mg/dL at discharge in the pre- and post-implementation groups was 37.2% and 54.6%, respectively (P<0.01; Figure 3). The median LDL-C level at discharge was 76 mg/dL (IQR 65–93 mg/dL) in the pre-implementation group and 68 mg/dL (IQR 56–80 mg/dL) in the post-implementation group (P<0.01), and the rate of achieving LDL-C <55 mg/dL at discharge in the pre- and post-implementation groups was 11.1% and 20.3%, respectively (P=0.012).

Figure 3.

Low-density lipoprotein cholesterol (LDL-C) at discharge before and after implementation of the clinical pathway. (A) Rates of achieving LDL-C <70 mg/dL in the pre- and post-implementation groups were 37.2% and 54.6%, respectively. (B) Median LDL-C levels at discharge were 76 mg/dL (interquartile range [IQR] 65–93 mg/dL) and 68 mg/dL (IQR 56–80 mg/dL) in the pre- and post-implementation groups, respectively. (C) Rates of achieving LDL-C <55 mg/dL at discharge in the pre- and post-implementation groups were 11.1% and 20.3%, respectively. In (B), the boxes show the IQR, with the median value indicated by the horizontal line; whiskers show the range.

Adherence to the Clinical Pathway

In the post-implementation group, 131 (80.4%) patients were treated via the clinical pathway. Reasons why the clinical pathway was not used are as follows: active treatment was deemed inappropriate due to old age, low activities of daily living, or cognitive decline in 6 patients; adverse drug events in 1 patient; and unknown reasons in 25 patients.

Lipid-Lowering Therapy Before and After Implementation of the Clinical Pathway

Regarding the breakdown of lipid-lowering therapy, the number of patients receiving intensive statin therapy increased significantly from 34.5% in the pre-implementation group to 79.8% in the post-implementation group (P<0.01). Ezetimibe use also increased significantly from 39.8% before implementation to 50.3% after implementation (P=0.04). The number of patients who received a combination of intensive statins and ezetimibe increased significantly from 22.6% before implementation to 44.2% after implementation (P<0.01; Table 2).

Table 2.

Lipid-Lowering Therapy at Discharge Before and After Implementation of the Clinical Pathway

	Pre-implementation group	Post-implementation group	P value
No. patients	226	163
Statin	206 (91.2)	158 (96.9)	0.0218
Intensive statin therapy	78 (34.5)	130 (79.8)	<0.0001
Ezetimibe	90 (39.8)	82 (50.3)	0.04
Intensive statin therapy + ezetimibe	51 (22.6)	72 (44.2)	<0.0001
Fibrate	4 (1.8)	1 (0.6)	0.3178
Eicosapentaenoic acid	4 (1.8)	1 (0.6)	0.3178
PCSK-9 inhibitor	1 (0.4)	1 (0.6)	0.816

Unless indicated otherwise, data are presented as number of patients (%). PCSK9, proprotein convertase subtilisin/kexin type 9.

Factors Associated With Achieving LDL-C <70 mg/dL at Discharge

Univariate logistic regression analysis demonstrated that implementation of the clinical pathway, a history of cerebrovascular disease, and ST-elevation MI were positively correlated with achieving LDL-C <70 mg/dL (odds ratio [OR] 2.03 [P<0.01], 2.21 [P=0.02], and 1.87 [P<0.01], respectively). In contrast, LDL-C levels on admission and a length of hospital stay ≤12 days were negatively correlated with achieving LDL-C <70 mg/dL (OR 0.99 [P<0.01] and 0.55 [P<0.01], respectively).

Multivariable logistic regression analysis was conducted to explore the factors associated with achieving LDL-C <70 mg/dL. The implementation of clinical pathways was significantly and independently associated with achieving LDL-C <70 mg/dL, even after adjusting for other relevant factors (OR 2.11; 95% confidence interval [CI] 1.36–3.27; P<0.01; Table 3). Other factors, namely ST-elevation MI, LDL-C levels on admission, and length of hospital stay ≤12 days, were also found to be independently associated with achieving LDL-C <70 mg/dL.

Table 3.

Logistic Analysis for Achieving LDL-C <70 mg/dL at Discharge

Variable	Univariate analysis			Multivariate analysis
	OR	95% CI	P value	OR	95% CI	P value
Clinical pathway implementation	2.03	1.35–3.06	<0.01	2.11	1.36–3.27	<0.01
High (≥75 years) age	1.31	0.86–2.00	0.21
Male sex	1.1	0.69–1.75	0.69
Ischemic heart disease	1.92	0.98–3.75	0.06	1.54	0.72–3.29	0.26
Hypertension	1.47	0.90–2.40	0.13	1.29	0.75–2.21	0.35
Diabetes	1.11	0.74–1.66	0.62
Smoking	0.77	0.50–1.16	0.21
Cerebrovascular disease	2.21	1.10–4.44	0.03	1.5	0.70–3.25	0.3
STEMI	1.87	1.11–3.14	0.02	2	1.13–3.53	0.02
LDL-C levels on admission	0.99	0.98–0.99	<0.01	0.99	0.98–0.99	<0.01
Statin use on admission	1.08	0.69–1.71	0.73
Length of stay ≤12 days	0.55	0.37–0.82	<0.01	0.58	0.37–0.90	0.02

CI, confidence interval; LDL-C, low-density lipoprotein cholesterol; OR, odds ratio; STEMI, ST-elevation myocardial infarction.

Factors Associated With Not Achieving LDL-C <70 mg/dL at Discharge in the Post-Implementation Group

The results of the univariate logistic regression analysis revealed that LDL-C levels on admission were positively correlated with not achieving LCL-C <70 mg/dL at discharge. In contrast, a history of ischemic heart disease, cerebrovascular disease, and smoking were negatively correlated with not achieving LDL-C <70 mg/dL. Multivariate logistic regression analysis was conducted to explore the factors associated with the non-achievement of the LDL-C goals in the post-implementation group. LDL-C levels on admission were significantly and independently associated with not achieving LDL-C <70 mg/dL, even after adjusting for other relevant factors (OR 1.012; 95% CI 1.003–1.022; P<0.01; Supplementary Table 1).

Discussion

In this study we examined the effectiveness of our region-wide clinical pathway, the Nagasaki AMI Secondary Prevention Clinical Pathway. The post-implementation group had a higher rate of intensive statin use, as recommended by the guidelines,⁸ and the rate of achieving the LDL-C target of <70 mg/dL was significantly higher than in the pre-implementation group (54.6% vs. 37.2%, respectively; P<0.01).

In implementing the clinical pathway, the recommended medication protocol must be accepted by each physician because it contributes to behavior changes.¹⁵ Before the implementation of the clinical pathway, the rate of intensive statin therapy from the acute phase of AMI was low, despite guideline recommendations. After implementation of the clinical pathway, the rate of intensive statin therapy increased significantly from 34.5% to 79.8%. This may be attributed to the fact that the clinical pathway was well approved and followed, resulting in standardization and elimination of variation among patients, physicians, and hospitals. Although a previous study in Japan used a lipid-lowering protocol in a single center,¹³ this report is the first of a multicenter study in which the number of PCI procedures and the number of physicians differed considerably between centers. The primary endpoint of this study, LDL-C <70 mg/dL at discharge, was achieved in 54.6% of patients, which is comparable to the 58% rate in the protocol-treated group in the previous study.¹³

A previous meta-analysis reported a 22% reduction in cardiovascular event risk with a 1.0-mmoL/L reduction in LDL-C.¹⁶ In the present study, LDL-C levels at discharge were 8 mg/dL lower in the post-implementation group than in the pre-implementation group. This suggests an estimated 4.5% reduction in cardiovascular event risk in this study. A cost-effectiveness analysis is also underway based on the data obtained in this study, the results of which will be reported elsewhere.

Assessing the rate of pathway adoption rate is also important in implementing the clinical pathway.¹⁷ Of the 163 patients in the post-implementation group in this study, 131 (80.4%) were treated using the clinical pathway. No prior studies have examined the pathway adoption rates, suggesting that other studies may not have focused on the implementation of the clinical pathway. In a previous study examining discharge medications, the use of intensive statins varied by center, with only 13 of 74 centers administering these drugs to more than 75% of patients.¹⁰ This suggests that the proportion of patients in our study who received intensive statins following the clinical pathway is sufficiently high, indicating that the pharmacotherapy protocols recommended in the clinical pathway are guideline based and accepted by many physicians participating in the study.

In Europe, guidelines recommend the early initiation of aggressive lipid-lowering therapy, and the LDL-C target for patients with ACS is set at <55 mg/dL, which is lower than in Japan.¹⁸ However, the rate of achieving LDL-C <55 mg/dL has been reported to be as low as 31%.¹⁹ The lack of structured clinical pathways, lack of medical coordination, and insurance restrictions on prescription drugs have been identified as barriers to achieving the targets.²⁰ To overcome these barriers, lipid management protocols for secondary prevention of AMI have been established and have been reported to be effective in many countries.^21,22 Educational programs for cardiologists in acute care hospitals²¹ and management goal sharing between specialists and primary care physicians²³ have been reported as effective methods. The optimal method varies from region to region, and it is desirable to that protocols are optimized for individual regions. The clinical pathway used in the present study was constructed considering the medical background in Japan, and we believe that it may be an appropriate method to overcome the barriers to lipid management in Japan.

However, this clinical pathway could not be adopted in some patients. In the post-implementation group, 32 of 163 patients (19.6%) were not treated using the clinical pathway. The reasons for not using the clinical pathway included adverse drug events in 1 patient and 6 patients being deemed ineligible by the physician, whereas the reasons for the remaining 25 patients are unknown. Compared to the pathway-treated group, the group in which the clinical pathway was not used had lower LDL-C on admission and fewer cases of ST-elevation MI. In the postimplementation group, there was no significant difference between the groups in which the pathway was and was not used, with 73 (55.7%) and 16 (50%) patients, respectively, achieving LDL-C <70 mg/dL at discharge. This may be due to the lower LDL-C levels at admission in the group in which the pathway was not used (Supplementary Table 2).

The incidence of statin intolerance in Japanese patients has been reported to vary, with ACS leading to discontinuation in 2–10% of cases.^24–26 In our study, only 1 patient experienced an adverse event despite intensive statin therapy, a lower number than in previous reports. Patients at high risk of adverse events may have been included in cases deemed ineligible by the physician and those who were not indicated for unknown reasons.

Next, we discuss the significance of implementing the clinical pathway in this region. There are 8 catheterization facilities in Nagasaki, all of which routinely refer post-AMI patients to local primary care physicians for the management of coronary risk factors. Prior to the implementation of the clinical pathway, specific LDL-C targets and methods for intensifying treatment for poorly controlled cases were not defined and were left to the discretion of individual physicians. The clinical pathway aims to establish standardized LDL-C targets and protocols for lipid-lowering therapy throughout the region to prevent recurrent ACS events. As a first step, this study has demonstrated enhanced lipid-lowering therapy in the acute setting and improved the rate of achieving LDL-C <70 mg/dL at discharge.

Study Limitations

This study has several limitations. First, this study collected data in the acute phase and did not assess lipid management in the chronic phase. As a first step in this research, we focused our analysis on how much the control status improved in the acute phase and the factors affecting it when all hospitals performing PCI in the region manage LDL-C levels using the same protocol. As the next step, we would like to collect and analyze data in the chronic phase following care by primary care physicians. Second, although guideline-recommended lipid-lowering therapy in acute care hospitals showed improvement, this study lacks insights into PCSK9 inhibitor use because data collection was confined to the acute phase. The clinical pathway recommends considering the initiation of PCSK9 inhibitor treatment if LDL-C levels remain above 70 mg/dL during the first outpatient visit after discharge. This aspect was considered in the analysis of the data from an extended period. Third, only 8 institutions in Nagasaki City were included in this study. A more comprehensive analysis involving more institutions in a wider area is required.

Our final goal is to standardize the implementation of guideline recommendations across the entire region to prevent subsequent attacks in patients with AMI. To achieve true effectiveness, it is important to obtain protocol approval and ensure adherence to the recommended practices in clinical settings. Further surveys addressing implementation barriers will be conducted among acute care hospitals and primary care physicians.

Conclusions

The implementation of a region-wide clinical pathway for secondary prevention of ACS in Nagasaki City yielded positive outcomes. Specifically, there was an increase in the rate of intensive statin therapy at discharge in patients with AMI, along with an improvement in the rate of achieving LDL-C <70 mg/dL at discharge. Sustaining the attainment of LDL-C targets is crucial for long-term secondary prevention of ACS. The next phase involves assessing the long-term effectiveness of this clinical pathway and its impact on patient prognosis in the near future.

Acknowledgments

The authors thank all the participating hospitals and members of the Nagasaki ACS Secondary Prevention Council for their efforts.

Sources of Funding

This study was funded by Novartis Pharma K.K. The statistical analyses were performed at the Department of Cardiovascular Medicine, Nagasaki University Graduate School of Biomedical Sciences. Novartis Pharma K.K., Tokyo did not have access to the original data. However, final approval and permission to submit the manuscript were obtained from the funder.

Disclosures

K.M. is a member of the Circulation Journal Editorial Team and reports receiving honoraria from Daiichi Sankyo, Novartis Pharma, and Pfizer. D.Y., M.T., and K.I. are employees of Novartis Pharma K.K., Tokyo, Japan. The other authors declare no conflicts of interest.

IRB Information

This study was approved by the Nagasaki University Hospital Ethics Committee (Approval no. 23011608, 2023).

Data Availability

The deidentified participant data will not be shared.

Supplementary Files

Please find supplementary file(s);

https://doi.org/10.1253/circj.CJ-24-0338

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