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Preference: Cardiology and Cardiac Surgery

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Relieving the pressure: new Australian hypertension guideline

The National Heart Foundation guideline has been updated to reflect recent evidence and Australian conditions

Some might think there are too many guidelines on hypertension.1–4 However, given that hypertension is a major risk factor for premature death and disability from cardiovascular disease in Australia and globally,5,6 practitioners need a practical, contemporary and localised guide to best practice. Most countries and their hypertension societies publish their own guidelines. However, these differ for a number of reasons. The data available at the particular time of publication vary. Experts interpret these data differently. To varying extents, guideline development is subject to vested interests, such as governments and other funders wishing to keep down costs, or industry wishing to make treatments available to the widest groups possible.7 The scope of the review can vary from people with uncomplicated hypertension to those with a broad range of complications and comorbidities.

In Australia, we are fortunate that the National Heart Foundation has produced an excellent new guideline (http://heartfoundation.org.au/for-professionals/clinical-information/hypertension) adapted for Australian conditions at a time when knowledge of the field has been moving rapidly.8

One of the first questions concerns who is at risk from hypertension and who warrants active treatment. For some time now, Australian recommendations have followed an absolute risk approach, rather than determining risk on blood pressure alone. The recommended way of assessing this is according to the national guideline on absolute risk developed by the National Vascular Disease Prevention Alliance.9 This predicts risk of a major cardiovascular event or death in the next 5 years based on a modified Framingham equation. Unless blood pressure is very high, it is a better way of identifying someone who will benefit from treatment than blood pressure alone as a single risk factor. It also helps deal with the well known epidemiological paradox that most people who have heart attacks or strokes caused by elevated blood pressure do not meet the conventional definition of hypertension. Systolic blood pressure in the high normal range (130/85–139/89 mmHg) carries risk and this includes a substantial proportion of the population. This applies equally to other risk factors such as blood glucose or lipids. Levels below arbitrary cut-points capture only some of the relevant risk.

However, risk assessed this way is very much influenced by age and is not applicable in young adults (aged under 45 years, or under 35 years in Indigenous Australians) or older adults (aged over 74 years).9

Recent hypertension trials and other guidelines have used several methods of assessing risk, including the presence or absence of target organ damage, clinical indicators such as abdominal girth, tobacco use, low levels of high density lipoprotein.10 What can be concluded is that there are many ways of assessing risk and, if risk is high, people benefit from modification of standard risk factors including blood pressure.

The 2016 guideline offers advice on new areas including out-of-clinic blood pressure measurement using ambulatory or home procedures, white coat hypertension and blood pressure variability. It includes updated evidence on the management of hypertension with comorbidities including chronic kidney disease, diabetes and peripheral arterial disease. There are minor updates to recommendations on first-line and combination pharmacotherapies.

A key area of debate surrounds the revision of treatment targets based on new evidence for a target blood pressure of < 120 mmHg in patients at high risk for cardiovascular events but without diabetes.11 Where supported by evidence, a target of < 140 mmHg is recommended. In other groups where there is supporting evidence, the recommendation is to aim for < 120 mmHg but be cautious about adverse events, especially in older, frail people. The debate is fuelled by the lack of data in particular patient groups but increasingly the clinical trial data are aligning with the epidemiology, with lower blood pressure being associated with better outcomes across the spectrum.12

The holes in the evidence base and shifting ground as new evidence comes forward are not helpful to the individual clinician who wants advice on what to do for a particular patient on a particular day. Further, we know that despite the proliferation of guidelines, most people with hypertension do not achieve the goals of their therapy, irrespective of what country they live in and what guideline is being followed. In future, we need to move the emphasis from large tomes written by expert groups to providing decision support individualised to the patient.

The new guideline also covers emerging evidence on diagnostic and therapeutic aspects of hypertension, including the uncertain role of renal denervation. It will guide management of hypertension in Australia for the immediate future. I commend it to readers of the MJA and thank all those who contributed to its preparation.

Detecting ascites

Most cases can be diagnosed by good clinical assessment at the bedside

The presence of ascites is a common physical finding and the detection of ascites is important for both diagnostic and prognostic reasons. Ascites is defined as the pathological accumulation of fluid in the peritoneal cavity.1 It may be due to a number of causes (Box 1). The most common is portal hypertension as a result of cirrhosis (> 75%) but malignancy (10%), heart failure (3%) and infection (2%) are other possibilities.1

Patients with ascites usually present to clinicians with increasing abdominal distension, weight gain and discomfort. However, ascites may be detected incidentally in patients developing other complications of their cirrhosis, such as variceal haemorrhage and encephalopathy. Moreover, a patient may present when their underlying heart failure or malignancy progresses.

Initial assessment of the patient will involve taking a history to determine the risk of liver disease. This will include questions about alcohol consumption and risk factors for chronic hepatitis, especially hepatitis C. Cardiac symptoms (shortness of breath and orthopnoea) can be assessed and patients should also be asked about symptoms that might indicate an underlying malignancy, such as weight loss and decreased appetite. Patients who do not complain of ankle swelling or abdominal distension are unlikely to have significant ascites.2

The examination of a patient with ascites includes two main components: inspection and palpation.

General inspection of the patient should include looking for signs of chronic liver disease, such as jaundice, spider naevi, palmar erythema, gynaecomastia and loss of body hair. Prominent collateral veins in the abdominal wall may also be present. Bulging flanks (Box 2) may be due to ascites or obesity, but the absence of this sign makes the presence of ascites unlikely.2

Palpation of significant hepatomegaly and splenomegaly may help the diagnostic process, but can be difficult to perform in a patient with a large volume of ascites or tenderness. With the patient lying supine with their head on a single pillow, there will be a tympanic area to percussion in the midline of the abdomen, which will normally be bordered by an area of dullness in either flank (Box 3). To assess this, the clinician should place their hand in the midline, parallel to the direction of the expected change in resonance, and percuss away from themselves until the percussion note changes from tympanic to dull. It is possible to repeat this manoeuvre in each direction. However, to demonstrate shifting dullness, the clinician will need to ask the patient to roll towards them, and on to the patient’s right side, while keeping their hand on the patient at the location of the dull percussion note. After waiting up to a minute for fluid to shift, the clinician can percuss once again from the tympanic area, which will now be in the flank, to the dull area, which will be in the midline. The sensitivity and specificity of this test for ascites is more than 70%.3

With a significant volume of ascites, it may be possible to elicit a fluid thrill or wave. This may require two people. The second person places the ulnar border of their forearm, or both hands, on the midline of the patient’s abdomen to prevent transmission of the thrill through the subcutaneous fat. The clinician then taps the flank firmly and feels for an impulse on the opposite side. This sign lacks sensitivity but is highly specific.3

Box 4, adapted from a review by Williams and Simel,3 summarises the significant symptoms and signs to consider when evaluating a patient with ascites, and their accuracy and precision. The absence of reported ankle swelling and abdominal distension, combined with no bulging flanks, flank or shifting dullness, are most helpful in excluding ascites. A diagnosis can be positively made when a patient has a fluid thrill together with shifting dullness and ankle swelling. Studies suggest high levels of agreement between clinicians, especially those with experience, on the detection of ascites using these techniques.2,4,5 Using ultrasound or computed tomography, the volume of ascites that can be detected is probably as small as 100 mL. However, it is unlikely that volumes of this magnitude will be detectable on clinical assessment. For flank dullness, more than 1 L of ascitic fluid needs to be present.

The gold standard for detecting ascites is aspiration of fluid after visualisation with imaging.3 However, with good clinical assessment, using the presence of a fluid thrill, shifting dullness and peripheral oedema as the positive indicators, the majority of cases can be diagnosed by a clinician at the bedside.

Box 1 –
Frequency of causes of ascites

Frequency

Cause

Very common

Cirrhosis

Common

Right-sided heart failure

Malignancy

Rare

Tuberculosis

Pancreatitis

Nephrotic syndrome

Very rare

Constrictive pericarditis

Budd–Chiari syndrome

Protein-losing enteropathy

Chylous ascites

Serositis (lupus, familial Mediterranean fever)

Box 2 –
Bulging flanks and abdominal distension secondary to ascites

Box 3 –
Tympanic area of the abdomen in the presence of ascites

Diagram courtesy of Rebecca Veysey.

Box 4 –
Significant pooled results for the accuracy of clinical history and physical examination in the detection of ascites*

Symptom or sign

Sensitivity

Specificity

Likelihood ratio†

Positive

Negative

Abdominal distension

87%

77%

4.2

0.2

Ankle swelling

93%

66%

2.8

0.1

Bulging flanks

81%

59%

2.0

0.3

Flank dullness

84%

59%

2.0

0.3

Shifting dullness

77%

72%

2.7

0.3

Fluid thrill

62%

90%

6.0

0.4

* Adapted from Williams and Simel.3 † The likelihood that a symptom or sign would be expected if a patient had ascites: positive likelihood ratio indicates how much more likely the presence of ascites will be if the sign or symptom is present; negative likelihood ratio indicates how unlikely ascites would be if the symptom or sign were absent.

News briefs

Unnecessary EOL treatment widespread

University of New South Wales reviewers, reporting in the International Journal for Quality in Health Care, have found that more than a third of elderly patients hospitalised at the end of their life received “invasive and potentially harmful medical treatments”. The analysis of 38 studies over 2 decades, based on data from 1.2 million patients, bereaved relatives and clinicians in 10 countries including Australia, found that the practice of doctors initiating excessive medical or surgical treatment on elderly patients in the last 6 months of their life continues in hospitals worldwide. Dr Magnolia Cardona-Morrell, who led the research at UNSW’s Simpson Centre for Health Services Research, said rapid advances in medical technology have fuelled unrealistic community expectations of the healing power of hospital doctors and their ability to ensure patients’ survival. “It is not unusual for family members to refuse to accept the fact that their loved one is naturally dying of old age and its associated complications and so they pressure doctors to attempt heroic interventions,” Dr Cardona-Morrell said. “Doctors also struggle with the uncertainty of the duration of the dying trajectory and are torn by the ethical dilemma of delivering what they were trained to do, save lives, versus respecting the patient’s right to die with dignity.” The study revealed 33% of elderly patients with advanced, irreversible chronic conditions were given non-beneficial interventions such as admission to intensive care or chemotherapy in the last two weeks of life while others who had not-for-resuscitation orders were still given CPR. The researchers also found evidence of invasive procedures, unnecessary imaging and blood tests, intensive cardiac monitoring and concurrent treatment of other multiple acute conditions with complex medications that made little or no difference to the outcome, but which could prevent a comfortable death for patients.

Breast cancer treatment impacts independent living

Researchers from the US have found one in five women undergoing breast cancer treatment for a year became “incapable of performing some of the basic tasks required for independent living”. Published in Cancer, the study also found that a simple survey can help identify which women are at risk of such functional decline. Cynthia Owusu from Case Western Reserve University in Cleveland, Ohio, and her colleagues studied a group of 184 women aged 65 years and older who had been recently diagnosed with stage I to III breast cancer. The researchers used the Vulnerable Elders Survey, a 13-item self-administered tool that has been validated in community-dwelling elders to predict functional decline or death within 12 months. Patients completed the survey just prior to breast cancer treatment. Within 12 months, 34 of the 184 patients developed functional decline and seven died. The risk of functional decline or death rose with increasing survey scores. Women without an education beyond high school were disproportionately affected. “Our findings are important because the study validates the Vulnerable Elders Survey as a useful tool for identifying older women with breast cancer who may be at increased risk for functional decline within a year of treatment initiation,” she said. “This instrument offers the opportunity for early identification and will inform the development of interventions to prevent and address functional decline for those particularly at risk, such as women with low socioeconomic status.”

Commonly used drugs that can exacerbate heart failure

The American Heart Association have released their first scientific statement which outlines which commonly used medications and nutritional supplements could worsen or cause heart failure.

It helps medical professionals and patients avoid drug-drug or drug-condition interactions and provides information about natural supplements and remedies that could injure the heart.

Heart failure patients have an average of five or more medical conditions and could be on seven or more medications, all prescribed by different doctors.

“Since many of the drugs heart failure patients are taking are prescribed for conditions such as cancer, neurological conditions or infections, it is crucial but difficult for healthcare providers to reconcile whether a medication is interacting with heart failure drugs or making heart failure worse,” said Robert L. Page II, Chair of the writing committee for the new statement published in the AHA journal Circulation.

Related: MJA – Primary prevention of cardiovascular disease: new guidelines, technologies and therapies

Common over-the-counter NSAIDs and cold and flu preparations are included in the list of drugs that can damage the heart.

As many of these medications have high sodium content, they could exacerbate heart failure.

“For example, many cough, cold, and allergy and sinus preparations may have NSAIDs such as ibuprofen or vasoconstrictors such as phenylephrine or pseudoephedrine. Because both phenylephrine and pseudoephedrine exert their effects on adrenergic receptors, cardiotoxicity such as myocardial ischemia, MI, stroke, and arrhythmias can be seen with high dose and prolonged, excessive use,” the authors wrote.

When it comes to complementary and alternative medicine (CAMs), there is little quality efficacy or safety data to back up their use, Despite this, 38% of American adults use alternative medicines.

Related: Some things you should know about statins and heart disease

The authors say ‘natural’ products such as aconite, ginseng, gossypol, St John’s wort, green tea and licorice could be harmful in patients with heart failure or could interfere with heart failure medications.

Dr Page said patients need to be more vigilant about reading labels.

“Patients have been taught to read food labels for sodium content, but they also need to read labels on over-the-counter medications and natural supplements,” he said.

Healthcare providers should also conduct a comprehensive medication reconciliation at each clinical visit.

“Patients should be specifically asked about drug, dose, and frequency of all their medications, including OTC medications and CAMs,” the authors advised.

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Tissue deposition of protein fibrils causes a group of rare diseases called systemic amyloidoses. This Seminar focuses on changes in their epidemiology, the current approach to diagnosis, and advances in treatment. Systemic light chain (AL) amyloidosis is the most common of these conditions, but wild-type transthyretin cardiac amyloidosis (ATTRwt) is increasingly being diagnosed. Typing of amyloid fibrils, a critical determinant of therapy, has improved with the wide availability of laser capture and mass spectrometry from fixed histological tissue sections.

[Obituary] Robert Charles Strunk

Paediatrician and leading researcher in asthma. He was born in Evanston, IL, USA, on May 29, 1942, and died after a cardiac arrest in Chicago, IL, USA, on April 28, 2016, aged 73 years.

[Articles] Ixmyelocel-T for patients with ischaemic heart failure: a prospective randomised double-blind trial

To the best of our knowledge, ixCELL-DCM is the largest cell therapy study done in patients with heart failure so far. The transendocardial delivery of ixmyelocel-T in patients with heart failure and reduced ejection fraction due to ischaemic dilated cardiomyopathy resulted in a significant reduction in adjudicated clinical cardiac events compared with placebo leading to improved patient outcomes.

[Editorial] Self-medicating in the opioid crisis

On June 7, the US Food and Drug Administration released a drug safety notice about loperamide, an anti-diarrhoea medicine sold over the counter and under prescription. The drug is being used as a cheap and legally-available high, and to reduce the symptoms of opioid withdrawal. A standard dose for the medicine is 8 mg per day in divided doses, but opioid users have been taking massive doses of the drug, as much as 300 mg or more daily for weeks at a time. Taken in such high quantities, overdoses of loperamide can cause severe heart problems like ventricular arrhythmias, cardiac arrest, and death.

Diabetes drug lowers risk of heart attack, stroke

A glucose-lowering drug has been shown to safely lower the overall risk of heart attack, stroke or cardiovascular death among type 2 diabetes patients.

Patients who were at risk for cardiovascular disease were found to have a 13% lower risk of cardiovascular death, non-fatal heart attack or non-fatal stroke when they took the drug Liraglutide compared to those who took placebo.

The randomised, double-blind study assigned patients either liraglutide or placebo and followed them for an average of 3.8 years.

Study results found a 22% lower risk of cardiovascular mortality, 15% risk of all-cause mortality and 22% lower risk of new evidence of advanced diabetic kidney disease.

Related: Call for gastric surgery to treat diabetes

“It is exciting to see such a broad-based benefit for patients who took liraglutide because most prior trials of diabetes medications have not shown such benefits,” lead investigator John B. Buse from the University of North Carolina School of Medicine said.

“Our results should give patients and providers comfort that liraglutide can safely improve outcomes beyond the core treatment of type 2 diabetes.”

The results were presented at the American Diabetes Association’s 76th Scientific Sessions in New Orleans over the weekend and were published in the New England Journal of Medicine.

In another study presented published in NEJM, it was found that empagliflozin was associated with slower progression of kidney disease and lower rates of clinically relevant renal events in patients with type 2 diabetes at high risk for cardiovascular event.

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