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Current time:0:00Total duration:7:03

Video transcript

in this video we're going to talk about cardiac ablation and cardiac ablation is a procedure used to treat arrhythmias so an arrhythmia is a problem with the heart's electrical system that causes the heart to have an either abnormal rate meaning is too fast too slow or an abnormal rhythm and in the case of the abnormally fast heart rate that's called a tachyarrhythmia so in cardiac ablation diseased heart tissue known to cause an arrhythmia is found and then destroyed by destroying this problem area that starts arrhythmias you're hoping to prevent future arrhythmias cardiac ablation treat a variety of arrhythmias such as atrial fibrillation which is a condition where the atrial walls or the top chamber walls spasm it also treats atrial flutter which is another type of fast heart rate that stems from the top chambers ablation is used to treat ventricular tachycardia which is a fast heart rate stemming from the ventricles or the lower chambers and ablation trees tachycardia is caused by accessory pathways now an accessory pathway is a connection between the top chamber the atrium and the bottom chamber the ventricle that shouldn't be there so basically electrical signal escapes instead of going to the AV node stimulate the ventricles a little too early ablations also used to treat a condition called atrial ventricular nodal re-entrant tachycardia this is sometimes called a B and R T so avnrt is a fast heart rate caused by an abnormal loop of electrical activity going around the AV node so typically when people have an arrhythmia they'll go to a heart specialist and the heart specialist usually prescribes medications to treat the arrhythmia sometimes despite taking the medications people will still have the earth Meah so if medications don't work then they might try something called electroshock therapy or cardioversion anin cardioversion the hearts actually shocked with the goals of shot in the heart out of the rhythm and into a normal rhythm or rate sometimes cardioversion doesn't work either the person won't convert into regular rhythm or they'll go back to no rhythm and then go back to the arrhythmia so when somebody tries medication and cardioversion and are still having an arrhythmia well then they might try ablation now an ablation we're going in more destroying heart tissues that sounds pretty invasive however ablations are fairly non-invasive meaning we don't have to go crack open the chest and cut open the heart typically cardiologists can gain access through some sort of blood vessel and they often use a blood vessel at the groin now just as a side note in this diagram this heart is not to scale it's really big I made this heart big in this diagram just so you can see the vessels so again the cardiologists can gain access to the heart through a blood vessel and like I said they might go through the groin and they'll guide a series of tools through the vessels until that vessel reaches the heart they can either use a vein or they can go through an artery once inside the heart they're going to use these tools to locate the problem area and then the tool is used to destroy the problem area they usually burn it sometimes they freeze it but they usually burn it so destroy this area is called ablation and when they destroy this tissue it creates scar so scar doesn't conduct electrical signal therefore by destroying the tissue at and around the problem area you're preventing abnormal electrical signal from leaving this area because again scar doesn't conduct electricity some tachyarrhythmias are caused by focal points which are basically irritated area over fire so an example of this is v-tach or ventricular tachycardia like we talked about up here so this irritated diseased area of tissue over fires and send signal out to the rest of the heart and that causes the tachycardia the cardiologist will come in and they'll destroy this problem area again creating scar preventing signal from leaving the problem area the cardiologists are very careful to stay clear of structures that are critical to conduction such as the SA node and the AV node they stay clear of all these critical structures and only take care of the problem areas that are causing the arrhythmias tachyarrhythmias can also come from we entry circuits so a reentry circuit is an abnormal loop of electrical activity that goes around and around and around and that causes a fast heart rate and in these situations the cardiologist will go in and find an area called the critical isthmus the critical isthmus is a point in which all of the wavelets in this abnormal loop of electrical activity pass since everything passes through this area of tissue by destroying it you're going to terminate the loop and get rid of the tachycardia the critical isthmus is always the most narrow area of tissue that's safe to ablate again the cardiologists are going to stay clear of these important structures that are imperative for electrical conduction they only want to terminate the problem areas so some people who experience Hermia's can sense symptoms when they have them such as a fast heart rate or palpitations and a palpitation is basically the feeling or sensation that your hearts beating against your chest wall some people also feel dizzy it's important for these patients to be able to recognize these symptoms be able to take their pulse and know to call their health care provider in case they're having these symptoms why well because these arrhythmias can be very dangerous circulation gets so poor that the person might pass out or they can lead to other serious health problems such as stroke or even a worse arrhythmia a classic example is v-tach turning into another deadly arrhythmia called ventricular fibrillation and ventricular fibrillation the walls of ventricular spasm and no blood circulates and this will lead to death