Publications by authors named "Andrew I Macisaac"
Background: Air emboli are a life-threatening diagnosis, which may form through a range of mechanisms. In this case, we describe the case of extensive multi-territory air emboli in a patient with a history of intravenous drug abuse.
Case Summary: This case describes a 41-year-old male who presented with confusion following fall with long lie.
Article Synopsis
- Pericardial Decompression Syndrome (PDS) is a rare but serious complication that can occur after draining excess fluid from around the heart, leading to sudden drops in blood pressure and heart function.
- The case study highlights two patients who developed acute right ventricular failure right after procedures to relieve pressure on the heart, emphasizing this as a critical aspect of PDS.
- Current understanding of PDS is limited, but it's thought to be linked to heart mechanics, with complications that can lead to high rates of severe outcomes, underscoring the need for awareness and further research.
Objective: To assess whether hypertension is an independent risk factor for mortality among patients hospitalised with COVID-19, and to evaluate the impact of ACE inhibitor and angiotensin receptor blocker (ARB) use on mortality in patients with a background of hypertension.
Method: This observational cohort study included all index hospitalisations with laboratory-proven COVID-19 aged ≥18 years across 21 Australian hospitals. Patients with suspected, but not laboratory-proven COVID-19, were excluded.
Article Synopsis
- Patients with Type 2 Diabetes Mellitus (T2DM) have a higher burden of coronary artery disease (CAD) than those without diabetes, but this risk seemed to decrease over time from 2013 to 2019.
- A comparison of medication use showed that a higher percentage of patients with T2DM were on statins, RAS inhibitors, and anti-platelet drugs compared to non-diabetic patients.
- After accounting for medication usage, the difference in CAD severity between patients with and without T2DM disappeared, suggesting that preventative therapies may help mitigate the risk associated with diabetes.
Objectives: Describe the incidence of cardiac complications in patients admitted to hospital with COVID-19 in Australia.
Design: Observational cohort study.
Setting: Twenty-one (21) Australian hospitals.
Article Synopsis
- The study examines how telehealth usage in Australia surged during the COVID-19 pandemic, focusing on distinctions between telephone (TP) and video consultations (VC) among cardiology outpatients.
- It found that older patients and specific demographics favored TP, while VC patients tended to have earlier appointments and follow-up visits.
- Importantly, overall patient outcomes such as mortality and emergency department visits were similar across both telehealth modalities, indicating both can effectively maintain care access during the pandemic.
Introduction: The coronavirus 2019 disease (COVID-19) pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pre-existing cardiovascular disease (CVD) increases the morbidity and mortality of COVID-19, and COVID-19 itself causes serious cardiac sequelae. Strategies to minimise the risk of viral transmission to health care workers and uninfected cardiac patients while prioritising high quality cardiac care are urgently needed.
View Article and Find Full Text PDFBackground: Exercise capacity is frequently reduced in people with diabetes mellitus (DM) and may be due to subclinical cardiac dysfunction. Speckle-tracking echocardiography is now widely available; however, the clinical utility and significance of left ventricular (LV) strain and twist parameters remain uncertain. We hypothesized that LV strain and twist would be reduced in DM subjects during exercise.
View Article and Find Full Text PDFExercise capacity is frequently reduced in people with diabetes mellitus (DM), and the contribution of pulmonary microvascular dysfunction remains undefined. We hypothesized that pulmonary microvascular disease, measured by a novel exercise echocardiography technique termed pulmonary transit of agitated contrast (PTAC), would be greater in subjects with DM and that the use of pulmonary vasodilator agent sildenafil would improve exercise performance by reducing right ventricular afterload. Forty subjects with DM and 20 matched controls performed cardiopulmonary exercise testing and semisupine exercise echocardiography 1 h after placebo or sildenafil ingestion in a double-blind randomized crossover design.
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- TAVI is a treatment for severe aortic stenosis (AS), and this study evaluates differences between self-expandable valves (SEV) and balloon-expandable valves (BEV) in terms of procedural success and 30-day outcomes.
- A total of 151 patients were analyzed, finding similar procedural success rates but significantly higher complications like paravalvular aortic regurgitation, pacemaker insertion, and strokes in the SEV group compared to the BEV group.
- The study concludes that while mortality rates at 30 days are similar, SEV patients experience more complications than those with BEV after TAVI.
Article Synopsis
- * The Heart Team approach involves both doctors and surgeons in making treatment decisions, considering factors like frailty from geriatric assessments to determine the best course of action, whether it be TAVI, surgical options, or conservative management.
- * TAVI has become a standard procedure in Australia since 2018, with advancements leading to fewer complications and shorter recovery times, and it's anticipated that more elderly patients will require this life-saving treatment in the future
Article Synopsis
- - The study focuses on pregnancy-associated spontaneous coronary artery dissection (P-SCAD), reviewing demographics, management, and outcomes over time.
- - A total of 138 P-SCAD cases from 273 screened publications were analyzed, revealing significant improvements in management and outcomes, particularly from 2006-2016.
- - Maternal mortality dropped from 85% to 4%, and foetal mortality from 50% to 0% over the decades, linked to advancements like earlier angiography and conservative treatment strategies.
Article Synopsis
- The study compared microvascular function in patients with STEMI receiving thrombolysis and those with NSTEMI undergoing PCI, involving 17 STEMI and 20 NSTEMI patients.
- Results showed that the baseline microcirculatory function was significantly worse in the STEMI group, but both groups improved post-PCI.
- Notably, post-PCI IMR was linked to left ventricular function, indicating its potential as a predictor of recovery in STEMI patients.
Article Synopsis
- The study investigates the reasons for decreased exercise capacity in individuals with diabetes mellitus (DM), focusing on the roles of cardiac function and associated factors like co-morbidities and inactivity.
- Conducted with 60 participants, the case-control study compares type 1 and type 2 DM patients against healthy controls through exercise testing and echocardiography to assess heart function during physical activity.
- Results show that while type 2 DM participants had poorer exercise capacity and were less active than controls, these differences weren't linked to heart dysfunction, suggesting other factors may contribute more significantly to reduced exercise capacity in diabetes.
Article Synopsis
- The study examined the risks of percutaneous coronary intervention (PCI) in different weight categories: non-obese, obese, and morbidly obese patients, finding no significant differences in major adverse cardiovascular or cerebrovascular events among the groups.
- Obese patients were generally younger, more often female and diabetic, and had better renal function than non-obese patients. However, they required higher amounts of contrast and experienced increased radiation exposure during PCI.
- The findings suggest that while PCI is safe for obese and morbidly obese patients in terms of clinical outcomes, the related radiation exposure is higher and warrants the need for strategies to reduce it.
Article Synopsis
- The study aimed to evaluate if pulmonary microvascular disease can be detected in diabetic patients and how it affects their exercise capacity using a new echocardiographic technique called PTAC (pulmonary transit of agitated contrast bubbles).
- Sixty participants (40 with diabetes and 20 controls) underwent exercise tests and echocardiography to measure bubbles traveling through their lungs, with findings revealing more low PTAC in diabetics, especially those with microvascular complications.
- Results indicated that low PTAC was linked to decreased exercise capacity (24% lower VOpeak), reduced right ventricular function, and higher pulmonary artery pressures in diabetic patients, suggesting PTAC is a significant marker for pulmonary vascular health in this population.
Background: This paper presents a protocol for a randomised controlled trial of the Cardiac-Diabetes Transcare program which is a transitional care, multi-modal self-management program for patients with acute coronary syndrome comorbid with type 2 diabetes. Prior research has indicated people hospitalised with dual cardiac and diabetes diagnoses are at an elevated risk of hospital readmissions, morbidity and mortality. The primary aim of this study is to evaluate the effectiveness (and cost-effectiveness) of a Cardiac-Diabetes Transcare intervention program on 6-month readmission rate in comparison to usual care.
View Article and Find Full Text PDFBackground: Methamphetamine use is escalating in Australia and New Zealand, with increasing emergency department attendance and mortality. Cardiac complications play a large role in methamphetamine-related mortality, and it would be informative to assess the frequency of abnormal electrocardiograms (ECGs) amongst methamphetamine users.
Objective: To determine the frequency and severity of ECG abnormalities amongst methamphetamine users compared to a control group.
Background: Variation in the provision of coronary angiography is associated with health care inefficiency and inequity. We explored geographic, socio-economic, health service and disease indicators associated with variation in angiography rates across Australia.
Methods: Australian census and National Health Survey data were used to determine socio-economic, health workforce and service indicators.
Background: The index of microcirculatory resistance (IMR), an invasive measure of microvascular function, has been shown to correlate with clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI). The aim of this study is to evaluate the predictive value of IMR on left ventricular recovery in patients undergoing a pharmacoinvasive strategy for STEMI.
Methods: The index of microcirculatory resistance was assessed following percutaneous coronary intervention (PCI) in 31 patients with STEMI who were initially managed with thrombolysis.