A series of articles in The Lancet explored recent developments in the biology, treatment, and diagnosis of arrhythmias (abnormal heart rhythms), ahead of the AHA’s (American Heart Association’s) annual meeting in Los Angeles from November 3rd to 7th, 2012.

In arrhythmias, the patient’s heart beat is too fast, too slow or irregular. Over one million people in the United Kingdom are thought to be affected by some kind of arrhythmia. It is also one of the top ten reasons why patients are hospitalized.

Arrhythmias are associated with poor blood supply to the body, which can eventually lead to damage in the heart, brain and other organs.

Dr Andrew Grace, from Papworth Hospital and Cambridge University, England, said:

“The current landscape in arrhythmia management would be unrecognisable to practitioners twenty years ago. We’ve made massive strides, but there are still gaps, (for example), drug treatment remains an issue; the drugs are variably effective, with many side-effects. In relation to atrial fibrillation, my personal view is that much of that is due to metabolic factors, and with increasing obesity in the population, that’s going to be something of a problem.”

The Series also includes a profile on Dr. Grace.

Dr Dan Roden and Dr Grace explain that over the last few years, the development of empirical technologies for treating cardiac arrhythmias has “exceeded the pace at which detailed knowledge of the underlying biology has accumulated.”

Consequently, many clinical arrhythmias can be cured with new techniques, such as catheter ablation, but drug treatment and predicting the likelihood of sudden death is still lagging behind.

Their paper explains how the present state of the biology behind arrhythmias is. It also highlights the possibilities for improved and more accurate diagnoses, the prediction of risk, and targeted treatment decisions that a deeper understanding might offer.

The second Series provides an overview of catheter ablation, the main treatment for the most common types of arrhythmia.

Catheter ablation involves inserting catheters (thin, flexible tubes) into the heart using a key-hole approach through the veins. The damaged part of the heart that is causing the arrhythmia is targeted.

The authors wrote that “For many atrial arrhythmias the mechanism has been clearly defined and catheter ablation results in excellent long term outcomes.” Lead author, Professor Jonathan Kalman said that further research is required into what causes atrial fibrillation, especially on its underlying mechanisms.

The second Series provides a comprehensive overview of catheter ablation of atrial arrhythmias, and outlines which directions future research in this field might take.

In the third Series, senior authors, Dr Roy John and Professor William Stevenson explain why it is important to recognize the different kinds of ventricular arrhythmias, and their links to sudden cardiac death in people with heart disease. ICDs (Implantable cardiac defibrillator devices) significantly reduce the risk of sudden death for people with arrhythmias.

Although medications and catheter ablation might not prevent sudden death, they do lessen the arrhythmias that cause symptoms.

Dr John Camm, from St George’s University of London, England, suggests that future research should concentrate on new drugs and targeted ablation.

An Editorial that accompanied the Series concluded:

“With the expected rapid advances in understanding, and further translation of molecular evidence to the clinic, better treatment of cardiac arrhythmias and higher rates of prevention of sudden cardiac death are likely in the not too distant future.”

Written by Sarah Glynn