New non-invasive vascular monitoring system prompts widespread adoption of vascular profiling.
The arrival of the Omron VP-1000 Vascular Profiler in Australia brings simple, high-tech, ankle-brachial index (ABI) and pulse wave velocity (PWV) monitoring right into the GP surgery to improve diagnosis and treatment of cardiovascular disease.
The VP-1000 uses four pneumatic cuffs to simultaneously measure a patient’s blood pressure in all four limbs, providing waveform analysis and vascular evaluation. Accurate and reliable, the test can be performed in five to 10 minutes at the standard of classic Doppler-based measurements.
The principal behind the technology is that the more pronounced the atherosclerotic vascular disease in a given patient, the lower the ankle-brachial index reading.
Designed for use in both primary and specialist care, the Omron device is so simple and user-friendly that a practice nurse can be quickly trained to carry out the procedure, freeing up a physicians consulting time.
Ankle-brachial index testing is recommended by several international societies and by the Heart Foundation in the Management of Hypertension Guidelines.
Australia’s cardiovascular disease burden accounted for 46,134 deaths in 2005. It is a leading cause of disability affecting 1.4 million people in this country. 2 In the 2004 - 2005 National Health Survey, 19% of people questioned reported one or more long-term diseases of the circulatory system, which equates to 3.7 million Australians having an increased cardiovascular risk.
Elevated blood pressure is the leading cause of death globally causing seven million deaths each year. It is strongly associated with increasing rates of cardiovascular disease, peripheral arterial disease and cerebrovascular disease events and death.
A contributor to coronary heart disease, chronic heart failure, chronic kidney disease and their progression, hypertension is also the major stroke risk factor.
The total burden of cardiovascular disease, including peripheral arterial disease, is expected to increase over the next few decades as the Australian population ages.
As a result, the latest Heart Foundation Hypertension Guidelines recommend an evaluation of all patients with hypertension that includes:
- Physical examination of pulse rate, pressure etc.
- Dip stick testing of urine for blood and protein (microalbuminuria correlates with cardiovascular risk and the presence of end-organ damage).
- Blood analysis for sodium, potassium, cholesterol, triglycerides, etc.
- Echocardiogram to detect left ventricular hypertrophy, etc.
- Ankle-brachial index to detect peripheral vascular disease especially for patients who smoke, have diabetes, vascular bruits and are of older age. A finding of <0.9 is the diagnostic measure of the presence of peripheral vascular disease.
- Carotid Doppler for patients with bruits.
- Plasma aldosterone / renin ratio.
Associate Professor Markus Schlaich, Head of the Neurovascular Hypertension and Kidney Disease Laboratory at Melbourne’s Baker IDI Heart and Diabetes Institute, says the burden of blood pressure-related disease is a neglected priority and one of the most common causes of vascular disease.
"What’s most important to remember is that the link between hypertension and vascular disease in the majority of patients will not be evident through clinical symptoms and we need to undertake measures such as ankle-brachial index to detect these patients earlier and commence preventative therapy," he says.
"The guidelines recommend patients with diabetes, who smoke and have elevated blood pressure are all ABI tested because it is a clear measure of the presence of peripheral and most likely generalised atherosclerotic vascular disease."
In the German epidemiological trial on ankle brachial index (getABI), Professor Curt Diehm of the Affiliated Teaching Hospital in Karlsbad-Langensteinbach, Germany investigated the ankle-brachial index of 6,880 patients and found all cause mortality at the end of five years was 23.9% in 596 patients with symptomatic peripheral arterial disease (HR 1.8;p<0.001), 19.1% in 835 patients with asymptomatic peripheral arterial disease (HR 1.6; p<0.001) and 9.4% in 5,390 patients without peripheral arterial disease.
"We know patients with peripheral arterial disease die 10 years earlier than other patients and the idea behind this study was to investigate how often patients died of heart attack or stroke in a five year period," Professor Diehm says.
"GetABI confirms atherothrombotic disease often occurs in more than one vascular bed and the important role ankle-brachial index plays in determining disease presence.
"It clearly demonstrates that the incidence of coronary artery disease mortality triples in patients with peripheral arterial disease compared to those without it.
"This study indicates a third of the patients with cardiovascular problems that lead to mortality can be saved over a 10-year period."