Contemporary themes in acute coronary syndrome management: from acute illness to secondary prevention

Potential utility of B-Type natriuretic peptides in secondary prevention following percutaneous coronary intervention in remote communities of Western Australia

Introduction: A third of all acute coronary events that present in the Australian population occur in patients with established coronary heart disease. This study assessed the prognostic value of combined B-type natriuretic peptides (BNP) measurement and quantitative myocardial perfusion scan (MPS) data for cardiac events (CE).Material and methods: This retrospective cohort study involved 133 patients from rural Western Australia. The cut-off for normality was 6.0 for qualitative summed difference scores (SDS) of MPS and 400 pg/mL for BNP.Results: Patients with no CE had a mean SDS and BNP (1.52 with a 95% CI of 0.34 to 2.69), (175.9 with a 95% CI of 112.7-239.1) that was lower than patients with CE (6.54 with 95% CI 4.18-9.89) (P = 0.0003), (669.1 with 95% CI 543.9-794.3) (P < 0.0001). The sensitivity and specificity of combined testing for predicting CE respectively were 79.6% and 86.3% for SDS, 84.6% and 94.1% for BNP, and 100% and 92.7% for SDS and BNP combined.Discussion and conclusion: Elevated BNP is marginally superior to MPS in predicting CEs in patients who have previously undergone percutaneous coronary intervention (PCI); however, MPS can identify the region of myocardium most at risk. Routine BNP monitoring in this subgroup may serve as secondary prevention by identifying subclinical disease.

Cardiovascular outcomes of cancer patients in rural Australia

Background

Cancer and heart disease are the two most common health conditions in the world, associated with high morbidity and mortality, with even worse outcomes in regional areas. Cardiovascular disease is the leading cause of death in cancer survivors. We aimed to evaluate the cardiovascular outcomes of patients receiving cancer treatment (CT) in a regional hospital.

Methods

This was an observational retrospective cohort study in a single rural hospital over a ten-year period (17th February 2010 to 19th March 2019). Outcomes of all patients receiving CT during this period were compared to those who were admitted to the hospital without a cancer diagnosis.

Results

268 patients received CT during the study period. High rates of cardiovascular risk factors: hypertension (52.2%), smoking (54.9%), and dyslipidaemia (38.4%) were observed in the CT group. Patients who had CT were more likely to be readmitted with ACS (5.9% vs. 2.8% p = 0.005) and AF (8.2% vs. 4.5% p = 0.006) when compared to the general admission cohort. There was a statistically significant difference observed for all cause cardiac readmission, with a higher rate observed in the CT group (17.1% vs. 13.2% p = 0.042). Patients undergoing CT had a higher rate of mortality (49.5% vs. 10.2%, p ≤ 0.001) and shorter time (days) from first admission to death (401.06 vs. 994.91, p ≤ 0.001) when compared to the general admission cohort, acknowledging this reduction in survival may be driven at least in part by the cancer itself.

Conclusion

There is an increased incidence of adverse cardiovascular outcomes, including higher readmission rate, higher mortality rate and shorter survival in people undergoing cancer treatment in rural environments. Rural cancer patients demonstrated a high burden of cardiovascular risk factors.

Impact of Delay in Surgery on Outcome in Patients Undergoing Cardiac Revascularisation Surgery

BACKGROUND

Diagnosis of critical coronary artery disease, including after acute coronary syndrome presentation (ACS), represents an important indication for early coronary artery bypass graft (CABG) surgery. The study aims to investigate the influence of time from diagnosis to CABG on outcomes and document barriers to early revascularisation.

METHODS

All patients 18 years and older with an acute presentation due to ACS or critical coronary artery disease who were considered to require urgent inpatient cardiac surgery between January 2016-February 2019 were included in the study. The primary endpoints were 30-day all-cause mortality or readmission, 1-year all-cause mortality, all-cause readmission. The secondary endpoint was the rate of complications while waiting for surgery. The time duration between diagnostic coronary angiography and surgery was considered as the time interval.

RESULTS

Of 266 eligible patients, 251 underwent surgical revascularisation with 15 (6%) not undergoing surgery due to preoperative complications (n=12) or due to perceived prohibitively high surgical risk (n=3). The majority (85%) were male (mean age 67 years), 37% of patients had diabetes and 71% had hypertension. Non-ST elevation myocardial infarction was documented in 51% of the patients. The median time between diagnosis and inpatient CABG was 7 days (IQR 5-11). Thirty-five per cent (35%) of patients experienced complications while awaiting surgery. Of the 266 patients, 140 patients (53% - cohort 1) underwent surgery within 7 days. The cohort 1 rate of complications was lower than in cohort 2 (surgery after 7 days) (24 vs 47%, p<0.001). Moreover, 1-year mortality was less in cohort 1 (2 vs 8%, p=0.029).

CONCLUSION

In patients requiring urgent inpatient CABG, delay for more than 7 days is associated with a higher rate of in-hospital complications and worse 30 day and 12-month outcomes.

Missed Acute Myocardial Infarction (MAMI) in a rural and regional setting

Background

Delay in treatment and/or failure to provide reperfusion in ST-segment elevation myocardial infarction (STEMI) impacts on morbidity and mortality. This occurs more often outside metropolitan areas yet the reasons for this are unclear. This study aimed to describe factors associated with missed diagnosis of acute myocardial infarction (MAMI) in a rural and regional setting.

Methods

Using a retrospective cohort design, patients who presented with STEMI and failed to receive reperfusion therapy within four hours were identified as MAMI. Univariate analyses were undertaken to identify differences in clinical characteristics between the treated STEMI group and the MAMI group. Mortality, 30-day readmission rates and length of hospital stay are reported.

Results

Of 100 patients identified as MAMI (70 male, 30 female), 24 died in hospital. Demographics and time from symptom onset were similar in the treated STEMI and MAMI groups. Of the MAMI patients who died, rural hospitals recorded the highest inpatient mortality (69.6% p = 0.008). MAMI patients compared to treated STEMI patients had higher 30 day readmission (31.6% vs 3.3%, p = 0.001) and longer length of stay (5.5 vs 4.3 days p = 0.029). Inaccurate identification of STEMI on electrocardiogram (72%) and diagnostic uncertainty (65%) were associated with MAMI. The Glasgow algorithm to identify STEMI was utilised on 57% of occasions, with 93% accuracy.

Conclusion

Mortality following MAMI is high particularly in smaller rural hospitals. MAMI results in increased length of stay and readmission rate. Electrocardiogram interpretation and diagnostic accuracy require improvement to determine if this improves patient outcomes.

Continuity of care after percutaneous coronary intervention: The patient's perspective across secondary and primary care settings

Background:

Although patients may experience a quick recovery followed by rapid discharge after percutaneous coronary interventions (PCIs), continuity of care from hospital to home can be particularly challenging. Despite this fact, little is known about the experiences of care across the interface between secondary and primary healthcare systems in patients undergoing PCI.

Aim:

To explore how patients undergoing PCI experience continuity of care between secondary and primary care settings after early discharge.

Methods:

The study used an inductive exploratory design by performing in-depth interviews of 22 patients at 6–8 weeks after PCI. Nine were women and 13 were men; 13 were older than 67 years of age. Eight lived remotely from the PCI centre. Patients were purposively recruited from the Norwegian Registry for Invasive Cardiology. Interviews were analysed by qualitative content analysis.

Findings:

Patients undergoing PCI were satisfied with the technical treatment. However, patients experienced an unplanned patient journey across care boundaries. They were not receiving adequate instruction and information on how to integrate health information. Patients also needed help to facilitate connections to community-based resources and to schedule clear follow-up appointments.

Conclusions and implications:

As high-technology treatment dramatically expands, healthcare organisations need to be concerned about all dimensions of continuity. Patients are witnessing their own processes of healthcare delivery and therefore their voices should be taken into greater account when discussing continuity of care. Nurse-led initiatives to improve continuity of care involve a range of interventions at different levels of the healthcare system.

Survival after an acute coronary syndrome: 18-month outcomes from the Australian and New Zealand SNAPSHOT ACS study

OBJECTIVES

To assess the impact of the availability of a catheterisation laboratory and evidence-based care on the 18-month mortality rate in patients with suspected acute coronary syndromes (ACS).

DESIGN, SETTING AND PARTICIPANTS

Management and outcomes are described for patients enrolled in the 2012 Australian and New Zealand SNAPSHOT ACS audit. Patients were stratified according to their presentation to hospitals with or without cardiac catheterisation facilities. Data linkage ascertained patient vital status 18 months after admission. Descriptive and Cox proportional hazards analyses determined predictors of outcomes, and were used to estimate the numbers of deaths that could be averted by improved application of evidence-based care.

MAIN OUTCOME MEASURES

Mortality for ACS patients from admission to 18 months after admission.

RESULTS

Definite ACS patients presenting to catheterisation-capable (CC) hospitals (n = 1326) were more likely to undergo coronary angiography than those presenting to non-CC hospitals (n = 1031) (61.5% v 50.8%; P = 0.0001), receive timely reperfusion (for ST elevation myocardial infarction (STEMI) patients: 45.2% v 19.2%; P < 0.001), and be referred for cardiac rehabilitation (57% v 53%; P = 0.05). All-cause mortality over 18 months was highest for STEMI (16.2%) and non-STEMI (16.3%) patients, and lowest for those presenting with unstable angina (6.8%) and non-cardiac chest pain (4.8%; P < 0.0001 for trend). After adjustment for patient propensity to present to a CC hospital and patient risk, presentation to a CC hospital was associated with 21% (95% CI, 2%-37%) lower mortality than presentation to a non-CC hospital. This mortality difference was attenuated after adjusting for delivery of evidence-based care.

CONCLUSION

In Australia and New Zealand, the availability of a catheterisation laboratory appears to have a significant impact on long-term mortality in ACS patients, which is still substantial. This mortality may be reduced by improvements in evidence-based care in both CC and non-CC hospitals.

The transition from hospital to primary care for patients with acute coronary syndrome: insights from registry data

Despite guidelines advocating routine engagement with proven secondary prevention strategies, current uptake and access remain suboptimal. Australian registries of acute coronary syndrome have predominantly focused on inpatient care and have highlighted under-referral to cardiac rehabilitation, gaps in medication prescription and limited commencement of lifestyle change before discharge from hospital. Opportunities to improve equity, access and uptake of secondary prevention include better transition between acute and primary care, systematic delivery of prevention in primary care, workforce strengthening and embracing new technologies. Adopting a structured framework for delivery of secondary prevention in primary care will enhance continuity of care and improve coordination of services after acute coronary syndrome.

Eight challenges faced by general practitioners caring for patients after an acute coronary syndrome

The general practitioner is essential in the management of the patient who has recently been discharged from hospital following an acute coronary syndrome (ACS), particularly as duration of hospital stay is shorter than in previous decades. GPs caring for patients after an ACS face numerous challenges. Often, the first of these is insufficient or delayed documentation from the discharging hospital, although electronic discharge summaries are alleviating this problem. Post-ACS patients often have comorbidities, and GPs play a key role in managing these. Patients taking dual antiplatelet therapy who need surgery, and post-ACS patients with atrial fibrillation, require particular care from GPs. Patients will often approach their GP for advice on the safety of other drugs, such as smoking cessation medication, and phosphodiesterase type 5 inhibitors for erectile dysfunction. For patients complaining of persistent lethargy after an ACS, GPs must consider several differential diagnoses, including depression, hypotension, hypovolaemia, and side effects of β-blockers. GPs play an important ongoing role in ensuring that target cholesterol levels are reached with statin therapy; this includes ensuring long-term adherence. They may also need to advise patients who want to stop statin therapy, usually due to perceived side effects. Many of these challenges can be met with improved and respectful communication between the hospital, the treating cardiologist and the GP. The patient needs to be closely involved in the decision-making process, particularly when balancing the risks of bleeding versus thrombosis.

Optimising acute care and secondary prevention for patients with acute coronary syndrome

Ascertaining a patient's risk of ischaemic complications after admission with an acute coronary syndrome is an important determinant of management. The treating clinician must determine whether and how urgently to send the patient for coronary angiography and whether to select more intensive antithrombotic therapies in the acute phase, and facilitate secondary prevention strategies. Risk stratification is infrequently applied and, as a consequence, undertreatment of higher-risk patients is common. Ensuring routine application of risk stratification across hospitals may improve treatment of patients who have the most to gain from evidence-based therapies. This requires embedding standard practices into complex clinical environments, and includes the routine implementation of treatment algorithms in a permissive environment with clinical champions and support from the hospital administration. The implementation of routine systems of care defining prehospital, interhospital and individual hospital practice is challenging, but essential to minimise deficits in care.

Role of cardiovascular magnetic resonance in assessment of acute coronary syndrome

Cardiovascular disease (CVD) is the leading cause of death in the western world and is becoming more important in the developing world. Recently, advances in monitoring, revascularisation and pharmacotherapy have resulted in a reduction in mortality. However, although mortality rates have declined, the burden of disease remains large resulting in high direct and indirect healthcare costs related to CVDs. In Australia, acute coronary syndrome (ACS) accounts for more than 300000 years of life lost due to premature death and a total cost exceeding eight billion dollars annually. It is also the main contributor towards the discrepancy in life expectancy between indigenous and non-indigenous Australians. The high prevalence of CVD along with its associated cost urgently requires a reliable but non-invasive and cost-effective imaging modality. The imaging modality of choice should be able to accelerate the diagnosis of ACS, aid in the risk stratification of de novo coronary artery disease and avail incremental information of prognostic value such as viability which cardiovascular magnetic resonance (CMR) allows. Despite its manifold benefits, there are limitations to its wider use in routine clinical assessment and more studies are required into assessing its cost-effectiveness. It is hoped that with greater development in the technology and imaging protocols, CMR could be made less cumbersome, its imaging protocols less lengthy, the technology more inexpensive and easily applied in routine clinical practice.