pacemaker cells and the sa node

Usually, the heart muscle cells keep time more slowly than normal pacemaker cells. This allows the pacemaker cells within the SA node to be in control of generating and pacing the heartbeat. But, if a particular group of cells in areas remote from the SA node become extra- or hyper-excitable they can take over as the pacemaker for one or several beats, or for a longer term. You might think of the heart's cells as a schoolyard full of young boys playing soccer.

This allows the pacemaker cells within the SA node to be in control of generating and pacing the heartbeat. But, if a particular group of cells in areas remote from the SA node become extra- or hyper-excitable they can take over as the pacemaker for one or several beats, or for a longer term. You might think of the heart's cells as a schoolyard full of young boys playing soccer. Some are inherently quick and fast and are always on top of the game, while others usually play a little slower.

The sinoatrial node (SA node) is a group of cells positioned on the wall of the right atrium, near the entrance of the superior vena cava. Cells in the SA node will naturally discharge at about 70-80 times per minute. Because the sinoatrial node is responsible for the rest of the heart's electrical activity, it is sometimes called the primary pacemaker, the natural pacemaker.

Nerves don't make the heart beat. Cardiac muscle cells are the pacemakers. There's a primary group in the atria called the sinoatrial (SA) node. this fires the atria. the discharge then travels to the atrioventricular (AV) node which fires the ventricles. What they are probably talking about is either ablating (destroying) the SA node or AV node. Both are different and require different types of pacing.

Yes, the condition can infect the heart's natural pacemaker. The heart's "natural" pacemaker is called the sinoatrial (SA) node or sinus node. It's a small mass of specialized cells in the top of the heart's right atrium (upper chamber). It makes the electrical impulses that cause your heart to beat.

The SA Node, really a grouping of cells in the Atrial Area of the Heart, are responsible for controlling the Heart Rate. If the SA Node fails to function, the AV Node, between the Atria and Ventricles, will discharge and maintain the heart rate, although much slower then the SA Node Rate. A viruses have been known to attack the heart, I have a friend so afflicted.

Usually, the heart muscle cells keep time more slowly than normal pacemaker cells. This allows the pacemaker cells within the SA node to be in control of generating and pacing the heartbeat. But, if a particular group of cells in areas remote from the SA node become extra- or hyper-excitable they can take over as the pacemaker for one or several beats, or for a longer term. You might think of the heart's cells as a schoolyard full of young boys playing soccer.

Hi the SA Node had a 40% blockage built up inside it and this was causing the SA Node to start having some form of spasms/seizures lasting approximatley a couple of minutes, during these spasm/seizures my heart rate would drop to 31bpm because not enough blood was being pumped into my heart during the spasm/seizure and as soon as the spasm/seizure would end my heart rate went back up to normal rate, this was causing me to collapse on each occassion and other symptoms which is why they fitted the

an overzealous SA node, 2). another focus that takes over for some reason and overrides the sa node and/or 3). a reentry circuit. I have 1 and/or 2 but not the third. Does anyone know for sure if the SA node is capable of firing at 60 and then jumping to 120ish for a run of beats? And do you know why this happens? Secondly, does anyone know why a second focus starts to override the SA node? Does anyone have input on SA node dysfunction?

s possible the damage to the nerve is part of the problem or it is possible the scarring from the ablation meant to fix the sa node is causing problems itself. I suspect the doctors are being cautious and maybe hoping it resolves on its own though the fact that the ablation was over a year ago that doesn't seem likely in my opinion. Unfortunately sa node modifications care a high risk of needing a pacemaker.

t discharge, there is another part of the electrical system in the heart, called the AV (Atrio Ventricular) Node, which will discharge and keep the heart beating. But the AV Node fires more slowly than the SA Node, therefore the heart may go too slow. In order to keep the heart rate sufficently fast, Doctors sometimes need to implant a Pacemaker that will discharge only when the SA Node fails to fire.

The SA node causes the atria to contract. As they contract the signal reaches the AV node which then fires the ventricles. The AV node doesn't generate a separate signal. If the atria and ventricles contract at the same time the heart would be very inefficient. This controlling mechanism keeps their contractions in rhythm. An ICD is needed when the ventricles have rhythm disturbances that occur in the ventricles that is leading to vtach which can turn into vfib.

So, in theory, yes an object buried in the av node, could sufficiently damage the cells and destroy the function of the av node.

Here is an excellent web page discussing Bradycardia and possible causes. http://cvi.med.nyu.edu/conditions-we-treat/conditions/bradycardia-bradyarrhythmia There is a nice graphic showing the construction of the heart, the SA Node (the heart's natural pacemaker), the AV Node (discharges in reaction to the SA Node Discharge or can Discharge Spontaneously if the SA Node fails to discharge in time.

These vessels are responsible for feeding the right atrium and most critically the sa node. A block in the sa nodal artery, or an acute block further upstream can be devastating as this sa node is the piece of tissue that functions as the primary pacemaker (electrical ticker if you will) of the heart. This is the first reason of many as to why heart attacks that occur on the right side are so complex and concerning.

DR says that the SA node was damaged during the surgery. My HR is normally 43 and dips into the 30s when sleeping. I know a pacemaker is in my future...this scares me greatly. I have been taking .5mg lorazepam to sleep because I can't seem to wrap my head around this... Please help ...

but has suggested to the cardiologist that the last resort is a pace maker ...AND an SA node ablation.... I cannot find much info on SA node ablation ... PLEASE HELP.. It must not be very common and my mind is saying very risky since there is not much info... Please give me resources.. info..

After doing research, I found that her SA and AV node could have failed. My question is, can temporary pacemaker and drugs treatment can recover SA and AV nodes. Or Permanent Pacemaker is the only option. If the permanent pacemaker is not fitted, what will her health status in near future. Please give your suggestions ASAP because I am undergoing a lot of stress and pain.

A very fast heart rate does not provide enough time for the heart's chamber to adequately fill and as a consequence the system may not get enough blood/oxygen and that includes the heart. Ischemia (lack of blood flow) to the heart cells can/will impair contractions leading to heart failure. Also a heart rate sustained above 100 bpm at rest stresses the heart and can cause heart enlargement and impair contractions resulting in heart failure and it can cause arrhythmia (irregular beats).

s natural pacemaker. The SA node discharges, the atrium contracts, the signal goes to the AV node, causing it to discharge, which causes the ventricles to contract. If the SA node doesn't discharge when it's supposed to, the AV node will eventually discharge on its own, but the rate will be much lower. This would be easy to see on an EKG, so that's likely the cause. Has anyone suggested a Demand Pacemaker to kerp the heart rate above a certain point?

These paths are form of tissue very similar to that of the AV node, and some physicians even consider them as part of the AV node. The slow path is the one usually targeted for ablation. AVNRT is a very common form of SVT, favoring females to males.

Thank you for your expert advice. It sounds as though (#5) intentionally ablating the SA node is not a wise decision as I may still have some problems but in (#7) you say it may be considered. So if I decide to try and have another ablation because I feel the technology is improved can the EP know that he is too close to the node and back off or is it "ooppps I got closer than I thought and burned the SA node....sorry!" kind of deal?

Sick sinus syndrome is usually when they ablate the sinus node and is characterized by the heart rate changing pace between fast and slow if I understand correctly. What I will say is I had avnrt that was corrected.

My cardiologist and an arrythmia specialist are advising me that I need to have a pacemaker implanted b/c of a defective SA node. I am 6', 180 lbs, have never been overweight, don't drink or smoke, like to run, hit a boxing heavybag, and work out with weights. Which pacemakers should I consider?

Here is a video that explains it - http://search.yahoo.com/search;_ylt=Aiw9j_BR1GNT0kxRzgNLa1JG2vAI?p=cardiac+action+potential+animation&fr=my-myy-s&toggle=1&cop=&ei=UTF-8 Na/K pass in and ut of cells to generate a change in the membrane potential...

Then there is the wonderful back-up on the electrical system of the heart. The SA Node, in the Atrium, is the heart’s natural pacemaker. It discharges, the signal travels, and activates the AV Node, from there going into the ventricles. But what if the SA Node fails? Surprisingly, if the AV Node does not receive a signal from the SA Node, it discharges by itself, and causes the heart to beat. Mind you, the heart beats at a much slower pace, referred to as Bradycardia, but it does keep beating.

The top lead has been turned off. I understand the electrical signal begins from the SA Node, and when the rt. and left atria are filled with blood the signal causes the atria to contract which pumps the blood to the ventricles. Then normally the signal travels to the AV Node. Since I don't have an AV Node, how does the signal get to the bundle of His? Why would they have turned off the top lead? My doctor did not tell me he had done this.

Pacemaker cells and the sa node

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