Acute coronary syndrome (ACS), the clinical manifestation of coronary artery disease (CAD) during an ischemic event, includes ST-elevation myocardial infarction (STEMI), non-ST-elevation myocardial infarction (non-STEMI), and unstable angina [1, 2]. ACS is recognized as the most common reason for patient presentation to emergency departments (EDs) [3]. The underlying pathophysiology of ACS results from acute coronary artery occlusion, predominantly caused by thrombus formation secondary to plaque rupture or coronary spasm [4]. ACS involves impaired reperfusion, which can lead to serious complications such as lethal cardiac arrhythmias, sudden death, cardiogenic shock, or heart failure [5, 6]. These outcomes highlight the clinical urgency of timely diagnosis and interventions.

Although the age-adjusted incidence of CAD is declining due to improved therapies [7], CAD remains the leading cause of mortality worldwide [8], including Australia [9], Europe [10, 11], and the United States of America [9]. Indeed, one in every ten deaths in Australian hospitals is attributed to ACS [12]. In cardiovascular medicine, the management of ACS has long been a critical challenge.

Given the high risk of in-hospital mortality in ACS presentations, accurately identifying ACS and chest pain patients, stratifying risk, and initiating evidence-based pharmacological and interventional management guidelines is critical [13, 14]. The American Heart Association (AHA), American College of Cardiology (ACC), Society of Cardiovascular Angiography and Interventions (SCAI) [15, 16], European Society of Cardiology (ESC), and National Heart Foundation of Australia and Cardiac Society of Australia and New Zealand [17] recommend well-defined guidelines for treating ACS patients.

The 2021 ACC/AHA/SCAI clinical practice guidelines for coronary artery revascularization recommend that people presenting with ACS and chest pain be managed through a structured clinical assessment pathway, supported by anatomical testing, point-of-care, and laboratory-based assays [17]. The management of ACS requires timely in-hospital emergency reperfusion, typically achieved by primary percutaneous coronary angioplasty (pPCI), which may include a drug-eluting stent (DES) or thrombolytic therapy [17]. For NSTEMI, invasive management is generally recommended, although timing may vary based on risk stratification and clinical presentation. In patients with STEMI, thrombolytic therapy remains an option when PCI is not immediately available [6]. The initial management includes antiplatelets, if not contraindicated, alongside pain management using opioids and sublingual nitroglycerin, and continuous cardiac monitoring. Subsequent treatments are based on a STEMI, NSTEMI, or unstable angina diagnosis. The AHA recommends that angiography and pPCI for STEMI be delivered within 90 minutes of presentation to preserve cardiac function [18]. Thrombolytic therapy is recommended if catheterization laboratory facilities are unavailable or patient transfer cannot be achieved within 120 minutes [18]. AHA guidelines also recommend maintaining door-to-needle time for thrombolytic administration to less than 30 minutes to optimize outcomes [18]. However, adherence to ACS guidelines varies, which may be attributed to patient, organizational, and differences in the availability of, and confidence in, the application of protocols and guidelines [1].

Thus, addressing gaps in current management and referral processes and practices is essential to improving ACS care. Therefore, this systematic review aims to identify the barriers faced by healthcare professionals to the implementation of ACS clinical guidelines in primary and tertiary healthcare settings. This review is distinct from previous systematic reviews, as this review evaluates barriers in the context of the newly released 2025 ACS guidelines, which introduce major changes, including updated antiplatelet therapy regimens, revised timing for invasive strategies, and a preference for radial access during PCI. These updates increase implementation complexity across diverse healthcare settings.

This systematic review was conducted using six electronic databases: EBSCO/Cumulative Index to Nursing and Allied Health literature, Cochrane Library, ProQuest, PubMed/Medline, ScienceDirect, and Web of Science to identify original empirical research published between 15 January 2016 and 15 June 2025. This systematic review methodology is based on the 27-item Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) checklist [19]. The protocol has been registered in PROSPERO (registration number CRD42023409325). Mixed Methods Appraisal Tool (MMAT) version 18 was used to appraise the quality of these studies [20].

To identify articles for inclusion, two reviewers (SS and SG) conducted an anonymized literature search, and an additional reviewer (VM) resolved conflicts. The search strategy incorporated Boolean operators and used Medical Subject Headings (MeSH) and text words in various combinations: (i) Evaluation terms: “barrier*” OR “challenge*” OR “Obstacle*”; (ii) population terms: (“NSTEMI *” OR “STEMI *” OR “Unstable Angina” OR “Acute Coronary Syndrome” AND “patient”); (iii) design terms: (“guideline*” OR “care pathway” OR “protocol”). Exclusion criteria included “review” OR “model” OR “provision of staff education/training interventions” OR “development” OR “risk” OR “prevalence” OR “etiology” OR “criteria” OR “update” (See Appendix A).

The search was limited to “human studies” and those published in English, which introduced language bias. No non-English studies were included due to translation limitations; however, future reviews may consider including these articles to mitigate this language bias. Gray literature was not included in this review; however, a hand search of reference lists identified no additional sources. All potentially relevant articles were imported into the EndNote 21 library for review in accordance with the inclusion and exclusion criteria. The original data search was conducted by authors SG and SS from 22nd of May to 29th of May 2023, and was updated by SS and VM between the 2nd of June and 15th of June 2025.

2.1 Study Selection

A total of 1625 articles were retrieved. A total of 67 duplicates were removed manually and using reference management software (EndNote version 21). Of the 1558 extracted papers, the titles and/or abstracts were screened for inclusion and exclusion using the Joanna Briggs Institute for Unified Management, Assessment and Review of Information (JBI Sumari). A total of 1482 articles were excluded, meaning 76 full-text articles remained for eligibility assessment; an additional 68 papers were excluded for various reasons. The final eight studies were used for the systematic review (Fig. 1, Ref. [19] and Table 1, Ref. [1, 21, 22, 23, 24, 25, 26, 27]).

Fig. 1.

PRISMA study selection process. Barriers to healthcare professionals in the implementation of ACS guidelines [19]. PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analysis; ACS, acute coronary syndrome.

Table 1. MMAT quality appraisal checklist for mixed-methods studies.

Study

S1

S2

1.1

1.2

1.3

1.4

1.5

3.1

3.2

3.3

3.4

3.5

VM

Bahiru et al. [22], 2018

Yes

Yes

Yes

Yes

Yes

Yes

Yes

NA

NA

NA

NA

NA

Yes

Stassen et al. [23], 2020

Yes

Yes

Yes

Yes

Yes

Yes

Yes

NA

NA

NA

NA

NA

Yes

Hertz et al. [24], 2020

Yes

Yes

Yes

Yes

Yes

Yes

Yes

NA

NA

NA

NA

NA

Yes

Crilly et al. [1], 2020

Yes

Yes

Yes

Yes

Yes

Yes

Yes

NA

NA

NA

NA

NA

Yes

Shaheen et al. [26], 2021

Yes

Yes

Yes

Yes

Yes

Yes

Yes

NA

NA

NA

NA

NA

Yes

Wihastuti et al. [27], 2019

Yes

Yes

Yes

Yes

Yes

Yes

Yes

NA

NA

NA

NA

NA

Yes

Varma et al. [21], 2023

Yes

Yes

NA

NA

NA

NA

NA

Yes

Yes

Yes

Yes

Yes

Yes

Bartnes et al. [25], 2022

Yes

Yes

NA

NA

NA

NA

NA

Yes

Yes

Yes

Yes

Yes

Yes

S1 = Are there clear research questions? S2 = Do the collected data allow the research questions to be addressed? Qualitative: 1.1 = Is the qualitative approach appropriate to address the research questions? 1.2 = Are the qualitative data collection methods adequate to address the research question? 1.3 = Are the findings adequately derived from the data? 1.4 = Is the interpretation of the results sufficiently substantiated by data? 1.5 = Does coherence exist between qualitative data sources, collection, analysis, and interpretation? Quantitative non-randomized: 3.1 = Is the sampling strategy relevant to address the research question? 3.2 = Is the sample representative of the population under study? 3.3 = Are the measurements appropriate? 3.4 = Is the risk of non-response bias low? 3.5 = Is the statistical analysis appropriate to answer the research question? VM = conflict resolution undertaken by an additional reviewer (VM). Key: yes = criterion is met; no = criterion is not met; NA = not applicable. MMAT, Mixed Methods Appraisal Tool.

This review critically synthesizes evidence on barriers to implementing ACS treatment guidelines, focusing on patient-, provider/staff-, and system/organizational/-level factors. Thus, by integrating findings from high- and low- to middle-income contexts, this review provides a broader understanding of the structural, economic, and cultural influences on guideline uptake. These insights offer practical implications for tailoring implementation strategies to diverse healthcare settings and inform policy priorities for resource allocation, workforce training, and equity in ACS care delivery.

Implementation of ACS guidelines is challenged by numerous barriers across different settings and contexts; meanwhile, patient characteristics, including age, gender, ethnicity, and geographical location, significantly influence the quality of care delivered [1, 21, 22, 23, 24, 28]. Clinical practice guidelines for patients with ACS recommend that patients receive antithrombotic therapy in the hospital; however, studies have shown that older patients and those with higher body mass index (BMI) are less likely to receive the recommended dose of antithrombotic therapy [30, 31]. Further, older patients and females experience disparities when attending the ED for chest pain and ACS, creating barriers to healthcare professionals adhering to ACS guidelines [31, 32]. Females are more likely to experience pre-hospital ambulance delays [33], less likely to receive an angiogram and revascularization [33, 34, 35], and are less likely to receive an ECG within 10 minutes of arriving at the hospital than men [33, 36].

Indigenous Australians are less likely to receive a coronary angiogram than non-Indigenous Australians, with contributing factors reported as a misdiagnosis of symptoms (16%), substitution with noninvasive procedures (8%), discharge against medical advice (11%), or other unclear reasons (36%) [37]. Geographical location is also another barrier to guideline adherence. People in rural and remote areas of Australia, for example, experience delays due to the distance to the closest health service [38]. A large systematic review indicates that delays in health-seeking behavior among people experiencing symptoms are attributable to limited patient awareness and knowledge [39]. A study of 60 hospitals in China found that the complexity of the condition, lack of recognition of symptoms in people with ACS (including requirements and resources of patients), low government support, movement of staff in ED, management quality, resistance from departments, and overwhelmed staff were barriers to staff knowledge [40]. The engagement of chest pain center staff was associated with knowledge scores; higher scores indicated greater motivation (OR, 1.79; 95% CI, 1.18–2.72), whereas lower knowledge scores indicated implementation barriers (OR, 0.81; 95% CI, 0.67–0.98) [40].

Staffing issues included the need for medical staff training in recognition, triage, and appropriate management of ACS. A study found that patients presenting to the ED had a 5.4-fold higher likelihood of not receiving appropriate triage assessments than those attending an outpatient clinic [7]. Gullick et al. [41] compared objective risk assessment using the Australian Global Registry of Acute Coronary Events (GRACE) Risk Tool with standard care for acute coronary syndromes. The study process and evaluation emphasized the implementation of the GRACE risk tool and highlighted the associated impact of the tool on patient management and outcomes. This may indicate that the tool aided clinicians in more accurately predicting risks and making decisions, potentially leading to improved treatment of cardiac presentations. Accurate in-hospital triaging and risk stratification are crucial to avoiding in-hospital death from acute ischemic events. Therefore, the knowledge of nurses regarding symptom identification, ECG interpretation, atypical presentations, and variations is essential in emergency departments and cardiac specialty areas [22, 42]. The model of care employed by nurse practitioners has been highlighted by Davis and Maness [43] as a critical approach to addressing gaps in healthcare facilities, particularly in rural and remote areas. According to guidelines, all patients with chest pain are recommended to receive an ECG within 10 minutes of presentation to the ED. This review reports that this achievement is limited. A study in Ireland using the Acute Coronary Syndrome Application (AcSAP) on Android tablets by experienced triage nurses found a significantly higher proportion of patients who received an ECG within 10 minutes (p 0.001) [44].

Recognizing obstacles and enablers specific to each hospital is crucial for the effective implementation of clinical strategies [45]. In this review system/organization, factors such as the importance of using the chest pain protocol and guidelines are vital. One study has suggested that the use of chest pain pathways may improve patient outcomes. They found that using chest pain protocols resulted in no deaths after 30 days post-discharge from 224 patients [46]. Patients in this same study had a low risk of adverse effects at 12 months post-discharge [46]. ACS pathways should include algorithms and decision-making models [47, 48]; however, not all health organizations adhere to standardized guidelines [49]. Implementation of ACS guidelines necessitates investigation of the persisting barriers. In non-interventional facilities, treatment must be initiated with medical therapy in accordance with guideline recommendations [46]. Other significant deficiencies include shortages of diagnostic equipment and logistical challenges, such as transport delays and fragmented care networks, that impede timely and effective care. In addition, the environmental factors and resource-related barriers in emergency departments further contribute to delayed ACS care [2, 5, 41, 47, 50]. A large systematic review also demonstrated that a lack of pre-hospital care, interfacility care coordination, and interventional cardiology was associated with poorer patient health outcomes [39].

Some facilities are constrained by therapeutic and diagnostic capabilities, resulting in underdiagnosed and undertreated ACS [23, 24, 50]. Across various studies, this review found a lack of essential resources, such as ECG machines, medications, and adequate training, and that organizational guidelines were a common barrier to care. Stassen et al. [23] found that resource constraints and transport delays are associated with high mortality among ACS patients. The authors also highlight the need for additional expert policymakers to address the data deficit in disease-burden data, as these gaps hinder effective resource distribution and allocation to affected local facilities. Meanwhile, delays in the referral system have always been a challenge for non-interventional facilities. Indeed, Jacobs et al. [51] found that STEMI care implementation was hindered by the absence of triage protocols, reperfusion strategies, interfacility transfer protocols, skilled staff to administer reperfusion therapy, and STEMI plans. These factors can adversely affect care delivery and lead to significant delays in initiating intervention [2, 17]. Healthcare settings must consider the physician-to-nurse staffing ratio, along with bed capacity, when allocating resources to patients undergoing PCI [33].

Overall, these findings highlight the need for targeted implementation strategies that address context-specific barriers. In high-income settings, interventions should focus on workflow optimization, role clarity, and adherence to updated protocols [1, 21, 25, 28]. In low-resource environments, policy priorities include investment in diagnostic infrastructure, workforce training, and financial protection for patients [22, 23, 24, 26, 27]. These insights can inform the design of continuing education and training programs for healthcare professionals that ensure alignment with current ACS guidelines. Digital health tools, such as mobile triage applications and standardized chest pain pathways, could accelerate guideline uptake globally [44, 46]. In addition, these health tools offer scalable solutions for improving ACS diagnosis and management and should be integrated into broader digital ACS care frameworks [49]. Therefore, health system redesign efforts should incorporate these strategies to enhance care coordination, reduce delays, and improve equity in ACS outcomes. Future research should evaluate the effectiveness of these strategies and explore scalable models for improving ACS care equity across health systems [50].

This systematic review revealed barriers that continue to hinder implementation of ACS guidelines in clinical practice, including the 2025 ACC/AHA/ASPC and the National Heart Foundation and Cardiac Society of Australia and New Zealand Guidelines. Effective healthcare system design and policymaking must prioritize skill maintenance, tailored education, and ongoing updates aligned with new evidence and guidelines. Future research should also incorporate service-delivery trials that directly address these barriers. Future research on service delivery would benefit from trials to address the barriers.

ACC, American College of Cardiology; ACS, acute coronary syndrome; AHA, American Heart Association; AKI, acute kidney injury; ARF, acute renal failure; CA, coronary angiogram; CAD, coronary artery diseases; CCL, cardiac catheterization laboratory; CCN, Coronary Care Network; ECG, electrocardiogram; ESC, European Society of Cardiology; MACE, major adverse cardiovascular event; NSTEMI, non-ST-elevation myocardial infarction; PCI, percutaneous coronary intervention; PCI-DES, percutaneous coronary intervention-drug-eluting stent (DES); SD, standard deviation; STEMI, ST-elevation myocardial infarction.

The datasets from this review are available from the corresponding authors upon reasonable request.

SG, SS designed the study. SG, SS, VM performed the review, analyzed data, contributed to the manuscript. XYH and DT contributed to the manuscript. All authors contributed to the conception and editorial changes in the manuscript. All authors read and approved the final manuscript. All authors have participated sufficiently in the work and agreed to be accountable for all aspects of the work.

Not applicable.

Not applicable.

This research received no external funding.

The authors declare no conflict of interest.

Supplementary material associated with this article can be found, in the online version, at https://doi.org/10.31083/RCM46736.