New test could be life-changing for people at risk of cardiac disease
“About 50% of the people we screen have unidentified heart disease, which is staggering," managing director of Health Screening NZ says. Photo / Getty Images
Predicting the risk of a cardiovascular event generally involves doctors looking at factors such as someone’s cholesterol levels and blood pressure, as well as medical history, age and weight.
Even when all of that is assessed, many people are missed. The risk prediction tool doesn’t put them at the threshold where they are identified as needing preventive treatment and the first symptom of vascular disease may be a heart attack or stroke.
GP William Ferguson believes we need to do better. In his West Auckland practice, he has conducted an informal trial of a piece of equipment he is convinced can make a difference.
A pulse wave analysis (PWA) machine is similar to a traditional blood pressure monitor (an inflatable cuff on the arm) but gives additional information. It analyses the shape of the pulse wave coming from the heart – the greater the reflected wave, the stiffer the blood vessels are and the higher the risk of a problem.
It also monitors central blood pressure, which has been shown to be a better predictor of vascular disease than peripheral blood pressure.
Ferguson tested a PWA machine on three groups of patients. One group was very healthy and considered low-risk, one was known to have arterial disease, and the third was somewhere in the middle.
“We didn’t really know how seriously we should take their cardiovascular risk, which, of course, is the central problem,” says Ferguson.
The test showed that many of the people in that intermediate zone had signs of vascular disease and were unknowingly on track to a heart attack or stroke.
“It made us sit up and take notice, leading us to be much more aggressive with preventive treatment or further investigation,” says Ferguson. “In some cases, we sent patients to a cardiologist or for a calcium score test [a CT scan that gives more information about how blocked the coronary arteries might be]. With others, we fine-tuned medication or got serious with lifestyle interventions.”
Ferguson said what was interesting was getting those patients to return for another PWA test six to eight weeks later and seeing the results of their interventions. “It made me realise the tool is really motivating for patients because they can see what is going on with their arterial health.