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What Causes Chronic Atrial Fibrillation?
Question: Hello,
I have two very random questions about pacemakers for one of your cardiologists.
Is there ever a time when a person could be a candidate for a pacemaker, but not a candidate for the implantable cardoverter-defibrillator kind of pacemaker? And, Does having chronic/on-going atrial fibrillation ever lead to the needing of a pacemaker?
I don't have any kind of heart problem. I'm just the kind of person who likes to understand how things work. And so far in my research regarding the heart and pacemakers, I haven't been able to find the answers to either of these two simple questions.
Thank you,
XXXX
I have two very random questions about pacemakers for one of your cardiologists.
Is there ever a time when a person could be a candidate for a pacemaker, but not a candidate for the implantable cardoverter-defibrillator kind of pacemaker? And, Does having chronic/on-going atrial fibrillation ever lead to the needing of a pacemaker?
I don't have any kind of heart problem. I'm just the kind of person who likes to understand how things work. And so far in my research regarding the heart and pacemakers, I haven't been able to find the answers to either of these two simple questions.
Thank you,
XXXX
Brief Answer:
There exist some important indication for your questions.
Detailed Answer:
Hello XXXX!
Thank you for asking on HCM!
Regarding your question I would explain to you as follows:
(1) The answer to your first question (Is there ever a time when a person could be a candidate for a pacemaker, but not a candidate for the implantable cardoverter-defibrillator kind of pacemaker?) is YES! There are medical indications for pacemaker implantation, separated form ICD need. For example the large chapter of atrio-ventricular conductance disturbances (second degree AV block, third degree AV block, high degree AV block, sino-atrial exit blocks, and also sick sinus syndrome which includes a variety of ECG patterns: from persistent bradycardia to supra-ventricular tachyarrhythmia and AB blocks). In these situations in general there is no need for ICD implantation concomitantly to pacemaker.
(2) Having a chronic atrial fibrillation doesn't imply necessarily a future need for pacemaker implantation. In general the major problem with atrial fibrillation is prevention a the uncontrolled ventricular response (so tachyarrhythmia).
In a very small proportion of Afib patients, does occur bradyarrhythmia (that is a very low ventricular response). In that case, when the patient is clinically symptomatic (episodes or presyncope and syncope), then an indication of pacemaker implantation is appropriate.
Hope to have fulfilled your expectations about the two selected questions.
If you have additional uncertainties, please feel free to ask me.
Greetings! Dr. Iliri
There exist some important indication for your questions.
Detailed Answer:
Hello XXXX!
Thank you for asking on HCM!
Regarding your question I would explain to you as follows:
(1) The answer to your first question (Is there ever a time when a person could be a candidate for a pacemaker, but not a candidate for the implantable cardoverter-defibrillator kind of pacemaker?) is YES! There are medical indications for pacemaker implantation, separated form ICD need. For example the large chapter of atrio-ventricular conductance disturbances (second degree AV block, third degree AV block, high degree AV block, sino-atrial exit blocks, and also sick sinus syndrome which includes a variety of ECG patterns: from persistent bradycardia to supra-ventricular tachyarrhythmia and AB blocks). In these situations in general there is no need for ICD implantation concomitantly to pacemaker.
(2) Having a chronic atrial fibrillation doesn't imply necessarily a future need for pacemaker implantation. In general the major problem with atrial fibrillation is prevention a the uncontrolled ventricular response (so tachyarrhythmia).
In a very small proportion of Afib patients, does occur bradyarrhythmia (that is a very low ventricular response). In that case, when the patient is clinically symptomatic (episodes or presyncope and syncope), then an indication of pacemaker implantation is appropriate.
Hope to have fulfilled your expectations about the two selected questions.
If you have additional uncertainties, please feel free to ask me.
Greetings! Dr. Iliri
Above answer was peer-reviewed by :
Dr. Pradeep Vitta
Dr. Ilir Sharka,
Thank you for your very helpful reply to my questions.
Given that your answer to my question (1) was so complete and comprehensive, I am now curious about the reciprocal question. But first, I have to ask you to clarify something I'm unclear about. You used the phrase "concomitantly to a pacemaker" in your answer. However, it has been my understanding that an ICD did the job of cardioverting, defibrillating, AS WELL AS pacemaking, meaning that someone would only need one implanted device and not two. Is this not the case?
So here is question (3). You told me when someone would NOT NEED an ICD. When WOULD someone NEED an implantable cardiovascular-defibrillator (ICD) as opposed to just a pacemaker alone?
And regarding my question (2), I understand the detailed response have given me; Thank you. But I need you to clarify something for me. I have always assumed that an implantable cardiovascular-defibrillator would be able to "defibrillate" a heart that was experiencing an atrial "fibrillation", and restore it to a normal rhythm. Is this just a semantic misunderstanding on my part? Is this not the kind of defibrillating an ICD does?
You have already exceeded my expectations with your answers to my two initial questions. And now I look forward to your answer to my one follow-up question, and your response to my request for clarification about my previous understanding on one issue, and my previous assumption on another issue.
Thank you,
XXXX
Thank you for your very helpful reply to my questions.
Given that your answer to my question (1) was so complete and comprehensive, I am now curious about the reciprocal question. But first, I have to ask you to clarify something I'm unclear about. You used the phrase "concomitantly to a pacemaker" in your answer. However, it has been my understanding that an ICD did the job of cardioverting, defibrillating, AS WELL AS pacemaking, meaning that someone would only need one implanted device and not two. Is this not the case?
So here is question (3). You told me when someone would NOT NEED an ICD. When WOULD someone NEED an implantable cardiovascular-defibrillator (ICD) as opposed to just a pacemaker alone?
And regarding my question (2), I understand the detailed response have given me; Thank you. But I need you to clarify something for me. I have always assumed that an implantable cardiovascular-defibrillator would be able to "defibrillate" a heart that was experiencing an atrial "fibrillation", and restore it to a normal rhythm. Is this just a semantic misunderstanding on my part? Is this not the kind of defibrillating an ICD does?
You have already exceeded my expectations with your answers to my two initial questions. And now I look forward to your answer to my one follow-up question, and your response to my request for clarification about my previous understanding on one issue, and my previous assumption on another issue.
Thank you,
XXXX
Brief Answer:
I would give the following explanations for you.
Detailed Answer:
Hello again XXXX!
(1) About the first question you are quite right. If the patient has indications for ICD implantation besides cardiac pacing, the device is the same, so we use one hardware device. But my phrase "concomitantly to a pacemaker" means another set up addition (that is addition of some circuits, software functioning and specialized intra-cardiac lead). So I was talking for therapeutic options (delivering of required missing functions), not about hardware conformation. That's my explanation.
(2) You are quite right, even for the second point. We generally use ICD implantation as a therapeutic option for life-threatening ventricular arrhythmia. Atrial fibrillation is not included in clinical indications of ICD implantation.
We don't use ICD for that purpose (atrial fibrillation conversion).
(3) Regarding your third question, I would explain that ICD implantation is required as I answered above for treatment of life-threatening ventricular arrhythmia. There exists a broad spectrum of ICD indications (ischemic and non-ischemic cardiac patients on high probability of experiencing life-threatening arrhythmia, such as VT, VF, torsades de pointes): like post myocardial infarction patients with low cardiac EF, non-ischemic dilated cardiomyopathy and low EF, patients with structurally heart disease who have experienced arrhythmic sudden cardiac death (SCD); hypertrophic cardiomyopathy and risk factors for SCD; arrhythmogenic syncope, some congenital rhythm disturbances (long QT syndromes, Brugada syndromes, etc), etc.
So there is a broad group of patients requiring ICD. If you are interested in enriching your knowledge on this issue, you may consult the official websites of ACC and ESC and the respective clinical guidelines.
Hope to have been helpful to you.
Best Regards! Dr. Iliri
I would give the following explanations for you.
Detailed Answer:
Hello again XXXX!
(1) About the first question you are quite right. If the patient has indications for ICD implantation besides cardiac pacing, the device is the same, so we use one hardware device. But my phrase "concomitantly to a pacemaker" means another set up addition (that is addition of some circuits, software functioning and specialized intra-cardiac lead). So I was talking for therapeutic options (delivering of required missing functions), not about hardware conformation. That's my explanation.
(2) You are quite right, even for the second point. We generally use ICD implantation as a therapeutic option for life-threatening ventricular arrhythmia. Atrial fibrillation is not included in clinical indications of ICD implantation.
We don't use ICD for that purpose (atrial fibrillation conversion).
(3) Regarding your third question, I would explain that ICD implantation is required as I answered above for treatment of life-threatening ventricular arrhythmia. There exists a broad spectrum of ICD indications (ischemic and non-ischemic cardiac patients on high probability of experiencing life-threatening arrhythmia, such as VT, VF, torsades de pointes): like post myocardial infarction patients with low cardiac EF, non-ischemic dilated cardiomyopathy and low EF, patients with structurally heart disease who have experienced arrhythmic sudden cardiac death (SCD); hypertrophic cardiomyopathy and risk factors for SCD; arrhythmogenic syncope, some congenital rhythm disturbances (long QT syndromes, Brugada syndromes, etc), etc.
So there is a broad group of patients requiring ICD. If you are interested in enriching your knowledge on this issue, you may consult the official websites of ACC and ESC and the respective clinical guidelines.
Hope to have been helpful to you.
Best Regards! Dr. Iliri
Note: For further queries related to coronary artery disease and prevention, click here.
Above answer was peer-reviewed by :
Dr. Pradeep Vitta
Answered by
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