Cardiology

Prof David Playford
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Why is coronary calcium score so important? Prof Playford, will explain why coronary CT is the single best test to identify the presence of coronary atherosclerosis, which is the actual pathology that causes AMI.

Dr Linda Calabresi
Clinical Articles iconClinical Articles
Dr Linda Calabresi
Clinical Articles iconClinical Articles
Columbia University Irving Medical Center
Clinical Articles iconClinical Articles

Due to it's perceived greater efficacy and the greater body of evidence supporting its use, chlorothalidone is preferred over hydrochlorothiazide for treatment of hypertension. A new study, recently published in JAMA Internal Medicine, may have cast this guideline into doubt.

A/Prof John Amerena
Monographs iconMonographs

SGLT2 inhibitors are rapidly becoming seen as cardiac drugs in their own right, above and beyond their role in diabetes.

Ohio University
Clinical Articles iconClinical Articles

Low-density lipoproteins (LDL), the kind of cholesterol found in fast food, processed meats and desserts, has come to be known as 'bad' cholesterol due to it's association with heart attacks and coronary disease. Despite this, 75% of heart attacks occur in patients whose cholesterol levels don't indicate they're at high risk, leading many to suspect the link isn't as simple as initially thought. Researchers at Ohio University may have just figured out why.

Dr Linda Calabresi
Clinical Articles iconClinical Articles

This week’s valuable resource award is a little different to the usual. Rather than a handy algorithm or useful assessment tool, this is, in fact an article from a recent Australian Prescriber. It’s about all the potential complications and side effects that can potentially occur with amiodarone, that reasonably popular drug that tends to get started in patients with AF and ventricular arrhythmias. In fact, the list of potential side-effects is quite extensive and not all that intuitive, particularly in elderly patients, which is why having this article bookmarked somewhere to be able to access at a moment’s notice is such a good idea.

Dr Stephen Gordon
Monographs iconMonographs

This article summarises, in the light of recent research, the current benefits and disadvantages of prescribing low-dose aspirin.

Dr Linda Calabresi
Clinical Articles iconClinical Articles

To ablate, or not to ablate? That is the question. That’s what international researchers were investigating in two studies just published in The Journal of the American Medical Association. And the answer? As so often happens in medicine, the answer is: it depends. Looking at the two studies, patients with symptomatic atrial fibrillation had a greater improvement in their quality of life at the one year mark if they had undergone catheter ablation than if they had been treated with medical treatment alone. But not to diminish the importance of quality of life as a measure of success, other findings from the latest research are also worth noting. In the larger of the two studies, a randomised controlled controlled trial of over 2200  patients presenting with symptomatic AF, researchers found after four years of follow-up that there was no significant difference in mortality between the group who had received catheter ablation and those who were treated with drug therapy alone. Similarly, the rate of disabling stroke, serious bleeding and cardiac arrest were the same between the two groups. As one would expect there was a higher rate of AF recurrence among the drug therapy group as compared with the catheter ablation group (70% vs 50%), however that 50% recurrence rate among those who’d undergone the ablation procedure is still pretty high and overall among that intervention group 19.4% underwent a repeat procedure. But the study authors who came from 10 different countries did not seem too deflated by the result. While their study failed to show benefit for catheter ablation in any of the primary outcomes such as death or stroke they did find some advantage in terms of secondary outcomes, including quality of life. They also point to a trend toward benefit of the procedure even if that benefit wasn’t large enough to reach clinical significance. The other JAMA study involved just 155 patients who had symptomatic paroxysmal or persistent AF and who were randomised to receive either catheter ablation or drug therapy. The Scandinavian researchers were particularly assessing their symptoms and their quality of life. After four years, the catheter ablation group ‘produced 14% more patients who achieved complete or near complete relief from their AF symptoms.’ What’s more the quality of life improved for patients in both groups. However, the improvement was greater in the ablation group. So, what does it all mean? Firstly, it needs to be pointed out that, in keeping with the guidelines the majority of patients included in these trials were symptomatic – only 10% were asymptomatic. In other words, there have to be symptoms or another very good reason to consider ablation in a patient with AF. Secondly, overall, the ablation group was more successful than the drug therapy group in relieving those symptoms. As an accompanying editorial puts it: “For patients with symptoms, in whom quality of life is impaired by AF, catheter ablation can improve quality of life to a greater extent than drug therapy. However, patients who choose drug therapy will also likely experience significant improvements in quality of life and have no worse risk for the most concerning complications of AF, stroke and death. Thus, there is no mandate for these patients to undergo catheter ablation at this time.” And that’s where we’re at.

Reference:

Packer DL, Mark DB, Robb RA, Monahan KH, Bahnson TD, Poole JE, et al. Effect of Catheter Ablation vs Antiarrhythmic Drug Therapy on Mortality, Stroke, Bleeding, and Cardiac Arrest Among Patients With Atrial Fibrillation: The CABANA Randomized Clinical Trial. JAMA. 2019 Mar 15. DOI: 10.1001/jama.2019.0693 [Epub ahead of print] Mark DB, Anstrom KJ, Sheng S, Piccini JP, Baloch KN, Monahan KH, et al. Effect of Catheter Ablation vs Medical Therapy on Quality of Life Among Patients With Atrial Fibrillation: The CABANA Randomized Clinical Trial. JAMA. 2019 Mar 15. DOI: 10.1001/jama.2019.0692 [Epub ahead of print] Albert CM, Bhatt DL. Catheter Ablation for Atrial Fibrillation: Lessons Learned From CABANA. JAMA. 2019 Mar 15. DOI: 10.1001/jama.2018.17478 [Epub ahead of print] Blomström-Lundqvist C, Gizurarson S, Schwieler J, Jensen SM, Bergfeldt L, Kennebäck G, et al. Effect of Catheter Ablation vs Antiarrhythmic Medication on Quality of Life in Patients With Atrial Fibrillation: The CAPTAF Randomized Clinical Trial. JAMA. 2019 Mar 19; 321(11): 1059-68. DOI: 10.1001/jama.2019.0335
Dr Nelson Chong
Clinical Articles iconClinical Articles

A stressful event, such as the death of a loved one, really can break your heart. In medicine, the condition is known as broken heart syndrome or takotsubo syndrome. It is characterised by a temporary disruption of the heart’s normal pumping function, which puts the sufferer at increased risk of death. It’s believed to be the reason many elderly couples die within a short time of each other. Broken heart syndrome has similar symptoms to a heart attack, including chest pain and difficulty breathing. During an attack, which can be triggered by a bereavement, divorce, surgery or other stressful event, the heart muscle weakens to the extent that it can no longer pump blood effectively. In about one in ten cases, people with broken heart syndrome develop a condition called cardiogenic shock where the heart can’t pump enough blood to meet the body’s needs. This can result in death.

Physical damage

It has long been thought that, unlike a heart attack, damage caused by broken heart syndrome was temporary, lasting days or weeks, but recent research suggest that this is not the case. A study by researchers at the University of Aberdeen provided the first evidence that broken heart syndrome results in permanent physiological changes to the heart. The researchers followed 52 patients with the condition for four months, using ultrasound and cardiac imaging scans to look at how the patients’ hearts were functioning in minute detail. They discovered that the disease permanently affected the heart’s pumping motion. They also found that parts of the heart muscle were replaced by fine scars, which reduced the elasticity of the heart and prevented it from contracting properly. In a recent follow-up study, the same research team reported that people with the broken heart syndrome have persistent impaired heart function and reduced exercise capacity, resembling heart failure, for more than 12 months after being discharged from hospital.

Long-term risk

A new study on the condition, published in Circulation, now shows that the risk of death remains high for many years after the initial attack. In this study, researchers in Switzerland compared 198 patients with broken heart syndrome who developed cardiogenic shock with 1,880 patients who did not. They found that patients who experienced cardiogenic shock were more likely to have had the syndrome triggered by physical stress, such as surgery or an asthma attack, and they were also significantly more likely to have died five years after the initial event. People with major heart disease risk factors, such as diabetes and smoking, were also much more likely to experience cardiogenic shock, as were people with atrial fibrillation (a type of heart arrythmia). A second study from Spain found similar results among 711 people with broken heart syndrome, 11% of whom developed cardiogenic shock. Over the course of a year, cardiogenic shock was the strongest predictor of death in this group of patients. These studies show that cardiogenic shock is not an uncommon risk factor in broken heart syndrome patients, and it is a strong predictor of death. They shed light on a condition that was previously thought to be less serious than it is. The evidence now clearly shows that the condition is not temporary and it highlights an urgent need to establish new and more effective treatments and careful monitoring of people with this condition.
A/Prof David Colquhoun
Monographs iconMonographs

This article discusses the importance of supplementary intake of marine omega-3 polyunsaturated fatty acids: (EPA) and (DHA) for patients post-acute myocardial infarction.

Dr Linda Calabresi
Clinical Articles iconClinical Articles

The physical health of mentally ill patients is a "massive problem and we are doing very badly at it,” psychiatrist Dr Matthew Warden told doctors at a recent Healthed evening seminar in Sydney. In particular, the prevalence of high cardiovascular risk among patients with a history of psychosis, means this population was a "ticking time bomb", said Dr Warden, who is the Director of Acute Inpatient Services for Mental Health at St Vincent’s Hospital in Melbourne. Even without antipsychotic medication, a disproportionate number of people with a history of psychosis are overweight or obese, do very little if any physical exercise and smoke. And it is well-known that the metabolic side-effects associated with antipsychotic medications increases this cardiovascular risk enormously. Consequently, there has been growing pressure on psychiatrists to assess, monitor and manage the physical health of their patients with psychosis, but Dr Warden said, realistically this needs to be also done by GPs as they will usually be managing these patients long-term and "they are better at it.” Baseline metabolic measurements need to be taken at first episode of psychosis, including weight, BMI, BP, lipid levels, fasting blood sugar and smoking status. Weight, in particular needs to be monitored carefully following the commencement of antipsychotic medication, as weight gain is extremely common, especially with olanzapine which, Australia-wide is the most commonly prescribed antipsychotic. In answer to a GP’s question following his talk, Dr Ward said it is extremely difficult to avoid or reverse this medication-induced weight gain with diet and exercise alone. In addition, weight loss pharmacotherapy such as phentermine is contraindicated in people with a history of psychosis. Key to managing the weight gain issue was to choose an antipsychotic with the least long-term side effects from the outset. Olanzapine and clozapine are associated with the greatest weight gain while lurasidone and the partial agonists, aripiprazole and ziprasidone have the least effect on weight. Alternatively, for patients who may have been started on olanzapine or similar, swap to a more weight-neutral medication at the first sign they were gaining weight or developing other metabolic side-effects. It is more likely that a person who as gained weight on olanzapine, will lose that weight if switched to another weight-neutral medication early. The longer that patient stays on olanzapine and the weight gain is sustained, the harder it will be to shift even if the medication is changed, Dr Warden said. In addition to managing weight gain in mentally ill patients, Dr Warden also encouraged GPs to offer smoking cessation advice and help. Even though this population were often considered among the most dependent and heaviest smokers, his own research had found a significant number of patients could successfully quit or at the least cut down given the right advice and assistance. While most smoking cessation pharmacotherapy could be used, Dr Warden suggested that varenicline (Champix) was probably best avoided in these patients. At St Vincent’s Hospital in Melbourne, patients receiving antipsychotic therapy have their metabolic markers assessed at admission and at regular intervals after that, including measuring their serum prolactin. “Hyperprolactinaemia is a significant problem and should be monitored every six months if it is elevated or increasing particularly if there are symptoms then either reduce the dose or change antipsychotic or add in low dose aripiprazole which will lower prolactin levels,” Dr Warden explained.   Dr Matthew Warden spoke on the “Management of Metabolic Dysregulation in Patients on Antipsychotics” at the Healthed, Mental Health in General Practice Evening Seminar held in Sydney in June, 2018.