Predicting Sudden Cardiac Arrest (SCA)

Increase in the number of sudden cardiac arrest (SCA) cases is of major concern now. Studies show that nearly thousand people die per day due to heart failure. One of the many reasons for the SCA is arrhythmia. Arrhythmia is a condition which shows irregular or abnormal heart beat. This could be because of the atrial fibrillation (abnormal contraction in atria) or ventricular fibrillation (abnormal contraction in ventricles).

Implantable ICD (implanted cardiac defibrillators) are used to treat arrhythmia. ICDs are implanted under the skin which monitors the heartbeat. It functions like pacemaker and also delivers short, high energy shocks to bring back the normal rhythm in case of irregularities. The latest research done by the University at Buffalo suggested the PET (Positron Emission Tomography) imaging can identify the patients who are at high risk of SCA. 

Researchers of University of Buffalo presented their clinical trial using PET imaging at Heart Rhythm Society’s 33rd annual scientific sessions. This imaging technique was used to analyse amount of damage done to the nerve of myocardium. In these cases, the sympathetic nerve is damaged or died due to lack of proper supply of blood. This is called denervated myocardium. The amount of damage done is analysed by imaging the hearts ability to take up the neurotransmitter released from heart neurons called norepinephrine by using Cyclotron-generated radiopharmaceutical 11C-hydroxyephedrine. 

John M Canty Jr., MD, professor in the UB School of medicine and biochemical sciences identified that those with 38 per cent of denervated myocardium are at the higher risk of cardiac arrest and are more suitable for the implantation of ICDs. This new method of predicting patients with sudden cardiac arrest risk for implantation of ICDs is most likely benefit many individuals.