LONDON – What was the top development in all of cardiology during the past year, the advance that holds the most far-reaching implications for clinical practice?
At the annual congress of the European Society of Cardiology, six experts each made a case for the biggest game changer in their discipline – risk prevention, electrophysiology, imaging, heart failure, percutaneous coronary intervention, and acute cardiac care. And when the audience of perhaps 400-strong had cast their votes, the winner was … the novel angiotensin receptor neprilysin inhibitor (ARNI) known as LCZ696 or valsartan/sacubitril. In the landmark PARADIGM-HF trial, the drug reduced the risk of cardiovascular death by 20% and heart failure hospitalization by 21% over and above what’s achieved with enalapril plus the other current guideline-recommended heart failure medications. “I’m a device person, but I’ve decided a device is not the most important recent innovation in heart failure,” Dr. Cecilia Linde said in her winning argument.
Dr. Cecilia Linde
“This ARNI is the first new drug in years with a very clear impact on morbidity and mortality. This is why I believe PARADIGM-HF is the most important study result of the last year in heart failure. It will directly impact treatment and will change the ESC guidelines for heart failure therapy. The PARADIGM-HF results suggest that the ARNI should be given as first-line therapy instead of an ACE inhibitor or angiotensin receptor blocker,” said Dr. Linde, professor and head of cardiology at the Karolinska Institute, Stockholm.
In the double-blind, randomized 8,399-patient PARADIGM-HF trial (N Engl J Med. 2014 Sep 11;371[11]:993-1004), the number needed to treat with LCZ696 instead of enalapril for 27 months in order to avoid one cardiovascular death or heart failure hospitalization was 21. The number needed to treat to avoid one cardiovascular death was 32.
Electrophysiology
The big news here is the concept of the autonomic nervous system as the master controller of atrial fibrillation, governing both the firing of arrhythmic triggers and the change in the arrhythmogenic substrate over time, according to Dr. Sabine Ernst of the National Heart and Lung Institute at Imperial College, London.
Dr. Sabine Ernst
“There is a new recognition of how the sympathetic and parasympathetic nervous systems interact to initiate and maintain arrhythmias. This will change the electrophysiology world forever,” she predicted.
Indeed, the future of antiarrhythmic therapy lies in neuromodulation of the autonomic nervous system, and it’s a lot closer than most cardiologists realize, according to the electrophysiologist.
She pointed to a recent study in which investigators at the University of Oklahoma Heart Rhythm Institute randomized 40 patients with paroxysmal atrial fibrillation to noninvasive low-level electrical stimulation of the vagus nerve or to sham treatment. The stimulation at 20 Hz suppressed atrial fibrillation and reduced levels of inflammatory cytokines (J Am Coll Cardiol. 2015 Mar 10;65[9]:867-75).
Vagus nerve stimulation was accomplished using a pair of clips attached to the external ear in order to access the tragus nerve. At just 20 Hz, participants felt no discomfort.
“This is just the very first step. It’s probably not the right frequency or intensity yet. But maybe – and I just want you to start to dream about this – just maybe this could be easily implanted in something we put in our ears. How nice it would be if we could add it to a hearing aid for a patient with atrial fibrillation; we would not need to bother with rate control anymore. Or to prevent atrial fibrillation, [we could put] a low-level vagus stimulator in the headphones for a smartphone,” Dr. Ernst said.
The noninvasiveness of this novel approach is what she finds most appealing.
“I want to stop putting catheters in other people’s hearts. I want to use a method I can ideally apply in the outpatient setting. I think we’ve got to move away from just destroying myocardium in patients with arrhythmias,” she said.
Cardiovascular prevention
Dr. Joep Perk nominated as the most important development of the past year in this field a new set of refined ECG screening criteria for asymptomatic hypertrophic cardiomyopathy (HCM) in athletes. Previous criteria – both the 2010 ESC criteria and the recently published Seattle criteria developed by an international collaborative group (Br J Sports Med. 2013 Feb;47[3]:122-4) – have unacceptably high false-positive rates, which lead to further testing, particularly in black athletes.
“In my personal experience, these young athletes start to think there is something wrong with their heart. They’ll be worried and might be erroneously disqualified. So even though we mean well, it does a lot of psychological harm,” said Dr. Perk, head of the department of internal medicine at Oskarshamn (Sweden) Hospital.