To Pace or Not to Pace: When do Pacemakers become Necessary?
A pacemaker is a medical device that generates electrical impulses to the heart to cause the heart muscle chambers to contract and deliver oxygenated blood to the body. Pacemakers are used when the heart is unable to pump effectively either due to an electrical conduction issue or structural issue.
In order to better understand the function of a pacemaker, lets take a look first at heart rhythms to get a better picture as to why pacemakers become necessary.
The heart’s pumping action is regulated by an electrical conduction system that coordinates the contraction of various chambers of the heart. This conduction system is like a synchronized dance that requires precise movement of each chamber at just the right time in order to function properly. Our heart beats about 100,000 times a day – that is about 60-80 beats per minute, in order to pump blood to our organs. A normal heart rate is considered to be between 60-100 beats per minute.
However, because our heart is always beating, there are times when it can begin to function abnormally, and in these cases proper evaluation and treatment is warranted to correct the problem.
There are several causes of abnormal heart beating and they are categorized as fast heart beats (tachycardia – heart rate faster than 100 bpm) or slow heart beats (bradycardia – heart rate slower than 60 bpm).
Types of Tachycardia include:
· Atrial Fibrillation – chaotic heart signal causing an uncoordinated heart rate
· Atrial Flutter – similar to Atrial Fibrillation but more organized
· Supraventricular tachycardia – broad term that includes arrhythmias that start above the lower heart chambers. This type of heartbeat causes a pounding heartbeat that begins and ends abruptly
· Ventricular Fibrillation – chaotic electrical signals causing the lower heart chambers to quiver instead of contracting. This can lead to death if the normal heart rhythm is not restored within a few minutes
· Ventricular Tachycardia – rapid regular heart rate that does not allow the ventricles to fill properly with blood so the heart is unable to pump enough blood to the body
Types of Bradycardia include:
· Sinus Bradycardia – the sinus node that is responsible for setting the pace of the heart does not work properly and fires at a rate of less than 60 beats per minute
· Conduction Block – A block in the heart’s electrical pathways can cause the signals that trigger the heartbeat to slow down or stop
Irregular heartbeats can occur for multiple reasons including:
· Heart attack or scarring from previous heart attack
· Block arteries
· High blood pressure
When there are conduction abnormalities it is important to identify where in the heart they are coming from so that proper treatment can be initiated.
Pacemakers are one form of intervention that is used when patients suffer from heart rhythms that are not sustainable to provide adequate blood flow to the body.
There are several common indications for pacemaker use:
1. Typically, bradycardic heart rhythms require the use of a pacemaker when a patient becomes symptomatic due to the slow heartbeat. Symptoms can include anything from lightheadedness and shortness of breath to fainting.
2. Heart blocks – when the electrical signal from the top of the heart does not conduct properly to the bottom chambers of the heart, thereby creating an irregular heartbeat that can cause palpitations, dizziness, shortness of breath, and fainting.
3. Post heart attack – heart muscle can die after a heart attack, causing a disruption in the electrical conduction in the heart. A pacemaker may be indicated in these instances to artificially help the heart muscles contract.
It is important that a cardiologist evaluate each patient thoroughly when there is suspicion of arrhythmias or slow heartbeats to make sure that the patient receives the care that they need to prevent further damage to the heart or possible death.
Pacemakers can be life saving devices and each situation should be evaluated individually to determine whether to pace or not to pace.
If you have a case involving the improper diagnosis and treatment of a cardiac arrhythmia, contact Weiser Nurse Consulting. We can review the records and identify possible breaches in standard of care.