Author: Dr Hitesh Patel
Around the globe, in developed countries, 1-2% of the adult population have heart failure, rising to over ten percent in those aged over 70 years. Heart failure occurs not just with reduced left ventricular ejection fraction, but also with preserved ejection fraction.– with figures steadily climbing year-on-year. However, despite the prevalence of modern-day interventions – namely telemonitoring and data collection – hospital admissions for heart failure continue to rise.
Here, Dr Hitesh Patel discusses just some of the new, and not so new developments in heart failure management, and that many ‘device measuring’ initiatives have failed to improve outcomes for heart failure patients.
Currently, those with severe systolic left ventricular dysfunction have a several percent annual risk of mortality and admission to hospital, even with the best treatment, explains Hitesh. “What’s important to remember when you are dealing with heart failure patients, is that people do die, even those with implanted defibrillators,” he says.
There is an array of implaned devices currently under investigation, including those working to improve contraction of the heart, those aiming to slow the heart down, alongside others that are working to increase vagal tone and increase contractibility. However, “we’re yet to see any benefit in terms of reduction of mortality from these amazing devices,” he adds.
The reality is ‘good ideas’ simply remain ‘good ideas’ until proven effective, explains Hitesh – and there are multiple examples of heart failure measures that affirm this truth.
“For example, if you look right back to telemonitoring, the whole idea was to capture data and to try to get some information before the patient deteriorated and ended up in the hospital. Some of the earlier studies involved taking people with heart failure – in those days enrolled participants called a toll-free number every morning and had to answer questions about their symptom status and maybe their weight,” he says. “It was then fed back to the site, and if there were any warning flags – indications the patient was developing congestion and needed more frusemide – a nurse would phone the patient up. It was a lot of work and a lot of effort – but this did not reduce important endpoints”.
What the trials said
Why? The proposed intervention can seem so logical and “seductive”, but what matters are the findings of randomised trials. The results from one large telemonitoring trials, Tele-HF – telemonitoring to Improve Heart Failure Outcomes trial – published in the New England Journal of Medicine in 2010, proved just that.
The multicentre, randomised, controlled trial – which involved recently hospitalised heart failure patients – revealed there were no reduction in the risk of hospitalisation for heart failure, the number of days in the hospital, or the time to readmission. Nor was there any, “Reduction in the risk of readmission or death from any cause with telemonitoring as compared with usual care,” reported the Journal.
One of the study’s authors concluded that the results indicate the importance of further independent evaluation of disease management strategies before the adoption, explains Hitesh.
“Whether it’s bio absorbable vascular scaffold – it doesn’t matter what – you have to prove that what we are doing makes a difference.”
Unfortunately, even more recent trials and analysis have failed to displace telemonitoring truths.
“As you know, a lot of the modern devices can transmit data – people can have implanted defibrillators that are recording data all the time – the patient goes to bed and the device transmits data through the modem that’s plugged into the power socket in the bedroom and the data is sent off,” explains Hitesh. “However, the results of a cardiac implantable electronic devices (CIEDs) trial, presented at the European Cardiac Meeting last year, showed us that they don’t make a difference to heart failure outcomes.”
Is there a case for remotely collected data?
The Remote Management of Heart Failure Using Implantable Electronic Devices trial (REM-HF) involved 1650 patients – randomised to receive either usual care or remote monitoring – each received one of three types of CIEDS for remote monitoring.
These three types were:
• A CRT-P device – cardiac resynchronisation therapy with a pacemaker.
• CRT-D device – cardiac resynchronisation with a defibrillator.
• ICD – an implantable cardioverter-defibrillator.
“The other thing these devices measured was something called impedance. It’s a measure of resistance between the tip of the right ventricular lead and the actual device and it correlates how wet your lungs are,” explains Hitesh. “If the impedance goes up, you are getting pulmonary oedema – maybe. But again, you have to collect all this information and if you don’t have 100 nurses sitting in an office, analysing all this data and phoning patients up, do you make a difference? What this trial demonstrated was no, you don’t make a difference.”
Co-principal trial investigator Martin R. Cowie, MD, from Imperial College London (Royal Brompton Hospital), thus concluded that, “If patients are well-treated already, and have well-controlled symptoms, looking at remotely collected data weekly is no better than usual care.”
So, there must be a better way – but which way? questions Hitesh.
“If you add mortality and admissions, the impact of heart failure on health care services increases yet again,” he says.
“There’s got to be a better way and there are people studying and analysing new devices – they’re implanting devices directly to measure either right ventricular pressure, left atrial pressure and even pulmonary artery pressure.”
Another investigations device provides CCM therapy – cardiac contractility modulation. How it works is the cardiac muscle – during an absolute refractory period – has electrical stimulation applied, known as ‘non-excitatory stimulation’. CCM encourages the movement of calcium ions into the cardiac muscle cells, without disrupting the natural cardiac rhythm – unlike a pacemaker or implantable defibrillator.
“There are some studies that have shown some benefit from some of these implanted devices but it’s not yet in clinical practice,” says Hitesh. “Maybe in the future some great ideas might come into play, or maybe they’ll come to nothing. We just have to wait and see.”