Arrhythmia basically is any heart rhythm that is not normal that a patient have. Some are deadly, some are not. As any rhythm, this also involves having a heart rate, how fast it is or how slow.
Can it sustain a life?
Cardiac monitors, electrocardiograms (ECG) are diagnostic equipments in assessing not only the heart rhythms but other cardiac problems.
For this post, I will focus mainly with heart rhythms/rate and try to simplify the most important things that we need to know, aka using lay man's terms as I can.
Abnormal rhythms and heart rates
When I was still learning about reading ECGs, we were given the rules on how it is done. Once we've learnt them, it wasn't that hard afterwards. As with anything in most things, having some RULES help to guide us in managing patients, especially in EMERGENCIES.
Heart rhythms
A normal heart rhythm, heart rate about 60 . Disclaimer: image from padresteve.com
With some abnormal rhythms, so long as the patient have a normal blood pressure, they have no symptoms of being compromised, medications are given in the hope that these will normalise the arrhythmias. If they don't work, then another management need to be done.
Heart rates
Normally, what we want for a heart rate is between 60-100 heart beat per minute. Outside these parameters are different medical names that pertains to a particular rate, it also tells the rhythm.
Confusing?
Extreme fast rate or low rate
Either way, these results cannot sustain a life. The heart can probably sustain it's function for a short while, but not for long. By the time the ambulance have brought the patients in the Arrhythmia Centre, the necessity of putting a device is a MUST to save a life. Most of the time.
Internal cardiac defibrillator or ICD
There are certain heart problems that make a person prone to having deadly fast rates that are higher than 150-200 beats, the rhythms would be Ventricular Tachycardia (VT) and Ventricular Fibrillations (VF). Where as with VT, some people can have this rhythm and still feel normal for few hours or longer, till the heart gets tired and they collapsed. VF is the deadliest, a person can die in seconds.
This is Ventricular Tachycardia, heart rate about 200, more or less. Disclaimer: image from floatnurse-mike.blogspot.com
In these rhythms, the heart chambers especially the Left Ventricle (LV) doesn't have enough time to fill with blood to pump out and perfuse major organs, the brain for example. Less perfusion with oxygen and a person gets confused. No perfusion causes a collapsed. Each time. The heart on another hand gets perfused when it's relaxing, not when it is pumping.
The reason that there are a lot of Defibrillators in public places is for easier access. Not just for paramedics but for anyone to access in an emergency. Even if a person have not used it before, it prompts you on what to do and where to put the chest pads. Anyone can save a life.
Kicked by a horse
Whoever started this explanation was brilliant, it does what it says exactly. The ICD kicks the abnormal rhythm out for the heart to start normally. Ideally.
We have had patients who got admitted for multiple shocks from their ICDs. But this is another issue.
Pacemaker or PPM
The heart have its' own pacemaker, the sino-atrial node (SA) in the right atrium. Normally, it stimulates the heart before it beats. To do this, there is a continous electrical conduction from the SA node to the atrio-ventricular (AV) node to the left and right Bundle Branches in the heart's ventricles.
Disclaimer: image from nataliescasebook.com
There is an origin of electrical conduction to an end-point, from the SA node to the AV node, then branching to the Bundle of His, before the heart contracts. Problem occurs when there is a dissociation from the normal activity. As the SA node regulates the heart rate, a dissociation can produce heart blocks, the deadliest is Complete Heart Block. The ventricles on their own can only beat for about 40 beats. Most people can tolerate this rate, the problem here is if other people don't and get compromised. Or the heart rate gets lower further. If not resolved by other means, then a PPM is needed.
A complete heart block, heart rate about 20 or less. Disclaimer: a screenshot image from emdocs.com
When the heart is having long pauses or in standstill, definitely it will need a PPM if it doesn't recover after immediate management like a temporary pacemaker. Anyone ever heard of Asystole?
Stimulate when needed or on-demand
Don't get confused, these are just settings that we used in one's PPM in accordance to what they need. As much as possible, if the heart can still do a bit of own stimulation, the setting will allow it to.
Some recap
There are a lot of causes why arrhythmias do occur. Patients' medical history, investigations, multiple disciplinary team's involvement play an important role in patients' management.
Although it is very easy for us to put these devices, our services warrant electrophysiology studies and managements in it's diagnosis and treatments as such.
Addendum for medics: Always, always treat the patient, not the ECG. Check the pulse!
Anyone, please feel free to ask, correct, emphasize or question anything you may have. Hope this is informative for you. I have included my previous post for more info.
https://steemit.com/health/@immarojas/a-pacemaker-at-11-years-of-age
Disclaimers: all images are not mine.
