In support of Heart Rhythm Week, an annual campaign designed to raise global awareness and understanding of arrhythmias, we invited world-renowned cardiologist Dr Kevin Campbell to answer your questions on the subject as part of an ‘Ask the Expert’ session. We would like to take this opportunity to thank our readers for their questions, and for their ongoing support of this fantastic cause. For more information on Heart Rhythm Week, and how you can get involved in raising awareness in your own community, please follow the link here.
The populations within developed countries are getting older and the treatment of other diseases, such as cancers, has improved considerably – should we expect mortality due to cardiac arrhythmias to increase steadily over the coming years?
Advances in the area of Cardiovascular Medicine and the treatment of heart rhythm disorders continue to progress every single year. We are always developing better and more effective ways to treat heart rhythm disorders and prevent sudden cardiac death. Moreover, public awareness of sudden death and its risk factors are also increasing. In order to limit mortality due to cardiac arrhythmias we must work diligently to improve training of the public in CPR and the use of automated external defibrillators (AEDs). Many studies have shown that by increasing the number of lay people who are able to assist in bystander CPR/AED use, we actually reduce the mortality associated with cardiac arrest. When AEDs are utilised in the field, survival goes from <5% to nearly 70%. It is essential with the aging population that we do a better job of training others, and promote bystander CPR/AED use in order to limit any increase in mortality
I have Type 2 diabetes, how do I reduce the risk of developing a rhythm disorder?
Type 2 diabetes is a risk factor for coronary artery disease (CAD). CAD can put you at risk of heart rhythm disorders—both benign and life threatening. When you have CAD you are at risk of having a heart attack. Heart attacks cause parts of the heart muscle to die and form scar tissue. This area of scar is a potential substrate for life-threatening arrhythmias such as ventricular tachycardia—associated with sudden cardiac death.
In addition, type 2 diabetes is associated with obesity. Obesity puts patients at risk of developing obstructive sleep apnoea (OSA). OSA occurs when your oxygen levels fall at night due to airway obstruction and snoring. This change in oxygen levels can have a detrimental effect on the heart—the ongoing airway obstruction can result in increased pressures in the heart chambers. This may result in the development of a heart rhythm disorder known as atrial fibrillation (AF). AF is the most common heart rhythm disorder in the world. It is associated with symptoms such as shortness of breath and fatigue but can also be complicated by stroke.
How important is the issue of metabolic syndrome when discussing the prevention of cardiac arrhythmias, as well as cardiovascular disease in general?
Metabolic syndrome can put you at risk of developing heart disease. In general, metabolic syndrome is a cluster of findings which include obesity, hypertension, hypertriglyceridaemia, glucose intolerance and insulin resistance. Recent studies have indicated that this syndrome is associated with an increased risk of developing atrial arrhythmias. In animal studies, metabolic syndrome has been shown to alter the structure of the sino atrial node – the pacemaker of the heart—and results in the generation of arrhythmias. In the US, over 1/3 of Americans have metabolic syndrome and many do not even know that they are at risk.
I have idiopathic polymorphic ventricular tachycardia (VT). I also have postural tachycardia syndrome (POTS). What role, if any, do you think that autonomic dysfunction plays in arrhythmia?
VT is not usually associated with POTS or autonomic dysfunction. More commonly POTS is associated with resting sinus tachycardia and episodes of postural hypotension and syncope. There is some association between autonomic dysfunction and arrhythmias. Most commonly in POTS there is a reactive sinus tachycardia that occurs with orthostasis.
My Daughter has the same mutation as me: Arrhythmogenic right ventricular dysplasia; not evident yet, but it wasn’t in me prior to sudden cardiac arrest – is it worth getting a home AED?
It is clear that AEDs save lives. If you are at risk of sudden cardiac death or have reason to believe that your family is as well, I think that the purchase of an AED is an important investment. While they remain expensive, many companies offer the sale of “refurbished” AEDs to private citizens—as long as the device is certified and remains under warranty this may be a great way to get an AED in the home at an affordable price.