Inpatient cardiac care for acute coronary syndromes in the Top End of Australia.

BACKGROUND: Disparities in cardiovascular outcomes between Aboriginal and Torres Strait Islander Australians and non-Indigenous Australians persist. This has previously been attributed to a combination of differences in burden of cardiovascular disease risk factors, and inpatient access to guideline-recommended care. AIMS: To assess differences in inpatient access to guideline-recommended acute coronary syndrome (GR-ACS) treatment between Aboriginal and Torres Strait Islander and non-indigenous patients admitted to Royal Darwin Hospital (RDH) with index ACS event. METHODS: This retrospective study included index ACS admissions (n = 288) to RDH between January 2016 and June 2017. Outcomes included rates of coronary angiography, percutaneous coronary intervention (PCI), surgical revascularisation, GR-ACS medications prescribed on discharge and short-term outcomes (30-day mortality and ACS readmissions; 12-month all cardiac-related readmissions). RESULTS: Two hundred and eighty-eight patients, including 109 (37.85%) Aboriginal and Torres Strait Islander patients, were included. Compared with non-indigenous patients, they were younger (median age 48 years vs 60 years; P < 0.01), with a greater burden of comorbidities, including diabetes (39% vs 19%; P < 0.01), smoking (68% vs 35%; P < 0.01) and chronic kidney disease (29% vs 5%; P < 0.01). There were no differences in rates of coronary angiography (98% vs 96%; P = 0.24) or PCI (47% vs 57%; P = 0.12), although there was a trend towards surgical revascularisation in Aboriginal and Torres Strait Islander patients (16% vs 8%; P = 0.047). There were no differences in 30-day mortality (1.8% vs 1.7%; P = 0.72), 12-month ACS readmissions (7% vs 4%; P = 0.20) or 12-month cardiac-related readmissions (7% vs 13%; P = 0.11). CONCLUSIONS: Aboriginal and Torres Strait Islander patients received similar inpatient ACS care and secondary prevention medication at discharge, with similar short-term mortality outcomes as non-indigenous patients. While encouraging, these outcomes may not persist long term. Further outcomes research is required, with differences compelling consideration of other primary and secondary prevention contributors.

Twelve-Month Outcomes of Patients With Myocardial Injury not Due to Type-1 Myocardial Infarction.

BACKGROUND: Diagnosis of acute myocardial infarction (AMI) requires a combination of elevated cardiac troponins, and clinical or echocardiographic evidence of coronary ischaemia. Identification of patients with a high likelihood of coronary plaque rupture (Type 1 myocardial infarction [MI]) is crucial as it is these patients for whom coronary intervention has been well-established to provide benefit and reduce subsequent coronary ischemic events. However, high-sensitivity cardiac troponin (hs-cTn) assays have increasingly identified patients with hs-cTn elevations not due to Type 1 MI where recommendations for ongoing care are currently limited. Understanding the profile and clinical outcomes for these patients may inform the development of an emerging evidence-base. METHODS: Using two previously published studies (hs-cTnT study n=1,937, RAPID-TnT study n=3,270) and the Fourth Universal Definition of MI, index presentations of patients to South Australian emergency departments with suspected AMI, defined by high sensitivity cardiac troponin T (hs-cTnT) greater than the upper reference limit (14 ng/L) and without obvious corresponding ischaemia on electrocardiogram (ECG), were classified as either Type 1 MI (T1MI), Type 2 MI (T2MI), acute myocardial injury (AI), or chronic myocardial injury (CI). Patients with non-elevated hs-cTnT (defined as <14 ng/L) were excluded. Outcomes assessed included death, MI, unstable angina, and non-coronary cardiovascular events within 12 months. RESULTS: In total, 1,192 patients comprising 164 (13.8%) T1MI, 173 (14.5%) T2MI/AI, and 855 (71.7%) CI were included. The rate of death or recurrent acute coronary syndrome was greatest in patients with T1MI, but also occurred with moderate frequency in Type 2 MI/AI and CI (T1MI: 32/164 [19.5%]; T2MI/AI: 24/173 [13.1%]; CI:116/885 [13.6%]; p=0.008). Of all the deaths observed, 74% occurred among those with an initial index diagnostic classification of CI. After adjusting for age, gender and baseline comorbidities, the relative hazard ratios for non-coronary cardiovascular readmissions were similar across all groups: Type 2 MI/AI: 1.30 (95% confidence interval 0.99-1.72, p=0.062); CI: 1.10 (95% confidence interval 0.61-2.00, p=0.75). CONCLUSIONS: Non-T1MI accounted for the majority of patients presenting with elevated hs-cTnT without ischaemia on ECG. Patients with T1MI had the highest rates of death or recurrent AMI; however patients with T2MI/AI and CI experienced a substantial rate of non-coronary cardiovascular re-hospitalisations.

Evaluation of the prescribing practice of guideline-directed medical therapy among ambulatory chronic heart failure patients.

BACKGROUND: Studies have demonstrated that heart failure (HF) patients who receive direct pharmacist input as part of multidisciplinary care have better clinical outcomes. This study evaluated/compared the difference in prescribing practices of guideline-directed medical therapy (GDMT) for chronic HF patients between two multidisciplinary clinics-with and without the direct involvement of a pharmacist. METHODS: A retrospective audit of chronic HF patients, presenting to two multidisciplinary outpatient clinics between March 2005 and January 2017, was performed; a Multidisciplinary Ambulatory Consulting Service (MACS) with an integrated pharmacist model of care and a General Cardiology Heart Failure Service (GCHFS) clinic, without the active involvement of a pharmacist. RESULTS: MACS clinic patients were significantly older (80 vs. 73 years, p < .001), more likely to be female (p < .001), and had significantly higher systolic (123 vs. 112 mmHg, p < .001) and diastolic (67 vs. 60 mmHg, p < .05) blood pressures compared to the GCHF clinic patients. Moreover, the MACS clinic patients showed more polypharmacy and higher prevalence of multiple comorbidities. Both clinics had similar prescribing rates of GDMT and achieved maximal tolerated doses of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) in HFrEF. However, HFpEF patients in the MACS clinic were significantly more likely to be prescribed ACEIs/ARBs (70.5% vs. 56.2%, p = 0.0314) than the GCHFS patients. Patients with both HFrEF and HFpEF (MACS clinic) were significantly less likely to be prescribed ß-blockers and mineralocorticoid receptor antagonists. Use of digoxin in chronic atrial fibrillation (AF) in MACS clinic was significantly higher in HFrEF patients (82.5% vs. 58.5%, p = 0.004), but the number of people anticoagulated in presence of AF (27.1% vs. 48.0%, p = 0.002) and prescribed diuretics (84.0% vs. 94.5%, p = 0.022) were significantly lower in HFpEF patients attending the MACS clinic. Age, heart rate, systolic blood pressure (SBP), anemia, chronic renal failure, and other comorbidities were the main significant predictors of utilization of GDMT in a multivariate binary logistic regression. CONCLUSIONS: Lower prescription rates of some medications in the pharmacist-involved multidisciplinary team were found. Careful consideration of demographic and clinical characteristics, contraindications for use of medications, polypharmacy, and underlying comorbidities is necessary to achieve best practice.

Diagnosis and management of acute coronary syndromes.

Acute coronary syndromes are a significant cause of morbidity and mortality in Australia. Outcomes are likely to be improved by rapid and accurate diagnosis, and early intervention The development of high-sensitivity troponin assays has revealed previously unrecognised types of myocardial injury, for which conventional management guidelines for myocardial infarction may not confer similar benefits. The distinction between myocardial injury and myocardial infarction has therefore become increasingly important Once the diagnosis of acute myocardial infarction has been made, individualised acute reperfusion strategies including percutaneous coronary intervention or fibrinolytic therapy should be considered. Secondary prevention strategies should be implemented before hospital discharge.

Impacts of high sensitivity troponin T reporting on care and outcomes in clinical practice: Interactions between low troponin concentrations and participant sex within two randomized clinical trials.

BACKGROUND: The impacts of high sensitivity cardiac troponin (hs-cTn) reporting on downstream interventions amongst suspected acute coronary syndrome (ACS) in the emergency department (ED), especially amongst those with newly identified hs-cTn elevations and in consideration of well-established sex-related disparities, has not been critically evaluated to date. This investigation explores the impact of hs-cTnT reporting on care and outcomes, particularly by participant sex. METHODS: Two similarly ED-based randomized controlled trials conducted between July 2011 to March 2013 (n = 1988) and August 2015 to April 2019 (n = 3378) were comparatively evaluated. Clinical outcomes were adjudicated to the Fourth Universal Definition of MI. Changes in practice were assessed at 30 days, and death or MI were explored to 12 months. RESULTS: The HS-Troponin study demonstrated no difference in death or MI with unmasking amongst those with hs-cTnT <30 ng/L, whereas the RAPID TnT study demonstrated a significantly higher rate. In RAPID TnT, there was significant increase in death or MI associated with unmasking for females with hs-cTnT <30 ng/L (masked: 11[1.5%], unmasked: 25[3.4%],HR: 2.27,95%C.I.:1.87-2.77,P < 0.001). Less cardiac stress testing with unmasking amongst those <30 ng/L was observed in males in both studies, which was significant in RAPID TnT (masked: 92[12.0%], unmasked: 55[7.0%], P = 0.008). In RAPID TnT, significantly higher rates of angiography in males were observed with unmasking, with no such changes amongst females <30 ng/L (masked: 28[3.7%], unmasked: 51[6.5%],P = 0.01). CONCLUSION: Compared with males, there were no evident impacts on downstream practices for females with unmasking in RAPID TnT, likely representing missed opportunities to reduce late death or MI.

Contrasting the potential benefits of early invasive coronary angiography in acute and chronic myocardial injury patterns.

BACKGROUND: In cases of evolving myocardial injury not definitively attributed to coronary ischaemia precipitated by plaque rupture, referral for invasive coronary angiography (ICA) may be influenced by observed troponin profiles. We sought to explore association between early ICA and elevated high-sensitivity troponin T (hs-cTnT) concentrations with and without dynamic changes, to examine if there may be a hs-cTnT threshold associated with benefit from an initial ICA strategy. METHODS: Using published studies (hs-cTnT study n = 1937, RAPID-TnT study n = 3270) and the Fourth Universal Definition of Myocardial Infarction (MI), index presentations of patients with hs-cTnT concentrations 5-14ng/L were classified as 'non-elevated' (NE). Hs-cTnT greater than upper reference limit (14ng/L) were classified as 'elevated hs-cTnT with dynamic change' (encompassing acute myocardial injury, Type 1 MI, and Type 2 MI), or 'non-dynamic hs-cTnT elevation' (chronic myocardial injury). Patients with hs-cTnT <5ng/L and/or eGFR<15mmol/L/1.73m2 were excluded. ICA was performed within 30 days of admission. Primary outcome was defined as composite endpoint of death, MI, or unstable angina at 12 months. RESULTS: Altogether, 3620 patients comprising 837 (23.1%) with non-dynamic hs-cTnT elevations and 332 (9.2%) with dynamic hs-cTnT elevations were included. Primary outcome was significantly higher with dynamic and non-dynamic hs-cTnT elevations (Dynamic: HR: 4.13 95%CI:2.92-5.82; p<0.001 Non-dynamic: HR: 2.39 95% confidence interval [CI]:1.74-3.28, p<0.001). Hs-cTnT thresholds where benefit from initial ICA strategy appeared to emerge was observed at 110ng/L and 50ng/L in dynamic and non-dynamic elevations, respectively. CONCLUSION: Early ICA appears to portend benefit in hs-cTnT elevations with and without dynamic changes, and at lower hs-cTnT threshold in non-dynamic hs-cTnT elevation. Differences compel further investigation.

Cardiac tamponade and constrictive pericarditis due to Actinomyces meyeri bacterial pericarditis: a case report.

Background: Purulent bacterial pericarditis (PBP) is a highly lethal infection of the pericardial space that arises as a complication of infective illnesses. Purulent bacterial pericarditis remains a diagnostic challenge given its non-specific clinical and investigative features and carries exceedingly high mortality rates due to fulminant sepsis and morbidity including constrictive pericarditis in survivors. We present our management of cardiac tamponade and subsequent constrictive pericarditis due to Actinomyces meyeri PBP. Case summary: A 53-year-old Caucasian male presented with acute New York Heart Association Class IV dyspnoea and chest discomfort, in the context of multiple hospital presentations over the preceding 8 weeks due to presumed recurrent viral pericarditis. On this admission, initial transthoracic echocardiography (TTE) demonstrated a large asymmetric pericardial effusion for which he underwent urgent pericardiocentesis. Serial TTE post-pericardiocentesis, however, demonstrated effusion re-accumulation and effusive-constrictive pericarditis, confirmed on cardiac magnetic resonance imaging. Fluid culture was positive for A. meyeri. He was diagnosed with PBP, but his condition deteriorated despite appropriate intravenous antibiotic therapy, necessitating semi-urgent surgical pericardiectomy. He recovered well and was discharged on Day 10 post-operatively. Discussion: Unlike uncomplicated acute viral or idiopathic pericarditis, PBP portends a very poor prognosis if unrecognized and untreated. Diagnostic challenges persist given its rarity in modern clinical practice; however, PBP should be considered in cases of seemingly recurrent pericarditis. Multi-modal cardiac imaging and careful analysis of pericardial fluid including cultures and lactate dehydrogenase/serum ratios may assist in earlier recognition. In this case, source control and symptom relief were achieved only with combined intravenous antibiotics, surgical evacuation, and pericardiectomy.

Managing asymptomatic severe rheumatic mitral stenosis in pregnancy: a case report.

BACKGROUND: Rheumatic heart disease (RHD) is a disease of disparity most prevalent in developing countries and among immigrant populations. Mitral stenosis (MS) is a common sequalae of RHD and affects females disproportionately more than males. Rheumatic MS remains a significant management challenge as severe MS is usually poorly tolerated in pregnancy due to haemodynamic changes and increased cardiovascular demands of progressing pregnancy. Pregnancy remains contraindicated in current management guidelines based on expert consensus, due to a paucity of evidence-based literature. CASE SUMMARY: A 28-year-old aboriginal woman with known severe MS was found to be pregnant during routine health review, despite contraceptive efforts. Echocardiography demonstrated mean mitral valve (MV) gradient 14 mmHg; stress echocardiography demonstrated increased MV gradient 28-32 mmHg at peak exercise and post-exercise pulmonary artery pressure 56 + 3 mmHg with marked dynamic D-shaped septal flattening. Left ventricular systolic function remained preserved. She remained remarkably asymptomatic and underwent successful elective induction of labour at 34 weeks. Postpartum, she remained euvolaemic despite worsening MV gradients and new atrial fibrillation (AF). She subsequently underwent balloon mitral valvuloplasty with good result. DISCUSSION: Severe rheumatic MS in pregnancy carries significant morbidity and mortality, due to an already fragile predisposition towards heart failure development compounded by altered haemodynamics. Pregnancy avoidance and valvular intervention prior to conception or in the second trimester remain the mainstay of MS management; however, we present an encouraging case of successful near-term pregnancy with minimal complications in a medically managed asymptomatic patient with critical MS, who subsequently underwent valvular intervention post-partum.