By Dr Maneesh Rai
Mangaluru, Nov 21: Sudden Cardiac Arrest (SCA) is the most unfortunate complication of a heart attack where in a normally beating heart comes to a complete stand still in seconds to a few minutes. Thankfully it is a very rare complication of a heart attack and occurs in less than 5% of all heart attacks. It is also important to realise that SCA can occur even in the absence of a heart attack.
The survival chances in the case of an unfortunate SCA is less than 10% even in most of the developed world. Restarting the ‘stopped’ heart within a minute will result in > 90% chance of survival. The chance of survival reduces 10% with every minute of delay, with very little chance of survival if the heart restarts after 10 minutes.
How to recognise a cardiac arrest and what should be done immediately?
Whenever a person suddenly collapses to the ground AND shows no signs of LIFE, it is a likely cardiac arrest. The key here is to recognise absence of signs of life i.e no response to verbal commands, not even a slight movement to pinch or pain and no signs of breathing. Anyone witnessing a SCA should quickly recognise the absence of signs of life in a suspected cardiac arrest victim (ideally in less than 30 secs) and immediately initiate CPR or Cardio-Pulmonary resuscitation. CPR, also called external cardiac massage, substitutes the work of the heart until a defibrillation can be delivered by an AED or a para medic to restart the heart. Timely CPR by a bystander is the only hope for a SCA victim. We as a community must be trained in CPR. It is a life-saving skill which anyone can learn including children. Early recognition, CPR and timely defibrillation is the key to increasing survival in SCA. The key thing to understand is that in a SCA the person who is likely to save the life is the bystander and not the doctor. How we as a community respond to SCA will determine the survival chances. Hence CPR training for all should be the norm.
How to prevent a SCA
While the overall risk of developing a SCA is very low in the general population, certain subsets of people may be at a higher risk. These include- persons with weak hearts or reduced pumping either because of a prior heart attack or otherwise, persons who have been diagnosed with life threatening Ventricular arrhythmias (a condition where the heart rate goes alarmingly fast in speeds upwards of 200 beats/min), survivors of cardiac arrest and persons with a strong family history of sudden cardiac arrest. It is important to understand that many of these non-heart attack causes of SCA are genetic with the potential to affect other members in the family in the future. Hence screening of family members of SCA victims is extremely vital. Such Individuals should be screened by an expert to evaluate the risk of a future SCA. If the risk if found to be high, many a times a defibrillator is implanted in the body. A defibrillator is a pacemaker like device which once implanted will monitor the heart beat for the next 7-9 years which is the typical life of a defibrillator battery. In the event of any dangerously rapid rhythm the defibrillator will recognise, deliver a shock and save life.
Dr Maneesh Rai is a cardiac electrophysiologist at KMC Hospital Dr B R Ambedkar Circle Mangaluru.