Today I will write about the options for treatment.
The cornerstone of atrial fibrillation management is divided into 2 categories: rate control and rhythm control. In other words, if the person is in persistent or permanent atrial fibrillation, are we able to control heart rate in the normal range both with rest, inactivity, and activity, or not. Heart rates tend to be on the high side with atrial fibrillation, so that we usually need to control heart rate with certain drugs that slow the ventricular rate, (the heart beat) into the normal range. Sometimes people may have heart rates that are too fast as well as too slow, so medications are required to slow the "too fast" side, and a pacemaker is required to maintain the heart beat from going too slow. As well, because of the increased risk of blood clot developing in the left atrial appenda ge, anti-coagulation is also a cornerstone of management to prevent a clot from traveling to the brain and causing a stroke.
The other strategy of management is called rhythm control: Are we able to provide the person with medication, or procedural work, to establish and maintain normal heart rhythm?
In order to decide which may be the best option (there are always choices), we need to assess the pattern of atrial fibrillation: how many times does it occur, the frequency, how long is the person in it for, or is it persistent, (or permanent), what is the underlying nature of the heart problem, and how symptomatic or asymptomatic are they? If a person is exquisitely symptomatic, the approach to the problem would be quite different from another person who has no symptoms at all! The first person would certainly require a strategy that could hopefully establish and maintain normal rhythm, and the second person could pursue both that option as well as consider rate control as the o ther option.
Restoration of normal sinus rhythm may improve heart function, exercise tolerance, and quality of life and these considerations must be assessed to determine which direction may be best suited.
An important study was presented in the New England Journal of Medicine in 2002 called the AFFIRM Study which looked at 4,060 patients all over age 65. In all patients, the atrial fibrillation was paroxysmal ( they were in and out of it) and they were divided into 2 randomized groups: Rhythm control with anti-arrhythmic drugs and if necessary, cardioversion, and Rate control, using drugs that slowed the heart rate down. There was a very subtle trend of increased mortality in the rate control group that was NOT statistically significant, and there was NO evidence that the rhythm control strategy protected patients from stroke more than the rate control strategy.
In terms of Risk Management decision making, a Major Decision is determining the risk of stroke and the appropr iate anti-coagulant for low, intermediate, and high risk patients.
15 to 25% of all strokes in the US can be attributed to atrial fibrillation. Risk factors that elevate stroke risk in AF are: male sex, valvular heart disease, cardiomyopathy and weak heart function, congestive heart failure, diabetes, smoking, advanced age, advanced coronary disease.
For each anti-coagulant, the benefit in terms of stroke reduction must be weighed against the risk of serious bleeding. If a person is younger, and healthy, with a healthy heart, their risk of stroke is in the 2 to 4% / year level. The older the person is, and adding up additional co-morbidities such as those mentioned above, increase the stroke risk to 6%, 8%, 10% and upwards to 15% per year. The risk of stroke or bleeding on an anti-coagulant, whether it be warfarin, or one of the new oral anti-coagulants is in the range of 2 to 2-1/2%. Therefore the argument holds that if you are young, well and healthy with recurrent and iso lated atrial fibrillation, perhaps you don't need to take an oral anti-coagulant because there is no risk/gain improvement. Then, an aspirin would be recommended. However, if you are older and you start adding on the various health issues described above, and your risk goes up per year of a stroke to 8-10-12-15%, and your risk of stroke or bleed is 2 to 3%, then I would ask you, what would you choose? It becomes more complicated with other circumstances as well. What if the person is elderly and has dementia? What if they are a significant fall risk? What if they have had a hemorrhagic stroke or a GI bleed or have a hematology problem that makes bleeding issues greater? With these issues, a clinical decision may be made with the patient and family that perhaps the risk of taking the anti-coagulant is greater than the reward.
The cornerstone of medical management for heart rate control involves 3 different types of drugs. The first is digitalis (digoxin, Lanoxin, Digitek). The second is the family of drugs called beta-blockers (propranolol, metoprolol, atenolol, etc.). The third is a group of drugs called calcium channel blockers ( diltiazem, verapamil, etc.) These drugs may also be used in combination, and it should be understood that every person is a unique human being and therapy must be careful individualized. If heart rates remain too fast despite these, or side effects are too great, then a procedure may be done called an AV node ablation with the addition of a pacemaker. This ablation seals off the AV node which is the relay switch transmitting electrical impulses from the atria down through to the ventricles. By ablating it, or sealing it off, the impulses don't go through, so the atrial fibrillation chaos in the upper chambers does not communicate to the ventricles. Therefore a pacemaker is put in place to drive the heart beat in the ventricles at a nice regular controlled rate. This eliminates the need for the above medications, except for the anti-coagulant, which would be continued.
To try and maintain normal sinus rhythm, there is a whole family of completely different drugs (sometimes used in combination with the above mentioned drugs) that are called anti-arrhythmic drugs and their job, once sinus rhythm is re-established, is to maintain the continuation of sinus rhythm. These drugs are more complicated, and they require a whole lot of finesse to use properly. It is pretty much the standard of care today that the only doctors who prescribe these medications are cardiologists and electrophysiologists (heart rhythm specialists). These drugs are pretty much beyond the domain of internal medicine specialists and family practitioners. These drugs only work so well, about a 50 to 70% overall success rate, though when successful on a given person can be 100% effective. These drugs need to be assessed carefully because they can sometimes cause a worsening of arrhythmia that can be dangerous. Therefore, when I am starting a new drug such as this with a patient, I will observe them for 2 or 3 days in the hospital, or I will have them take the first dose in my office and observe them for several hours and do repeated EKG's and then bring them back a few days later for a treadmill stress test.
The other topic of discussion is about atrial fibrillation ablation which has been in existence now for about 15 years. The technology has improved over the years and the experience of the ablation specialists has increased so that today it is a very acceptable option for people, particularly when one or two of the medications have been tried and haven't worked, either because of side effect problems or drug failure. I will not discuss this further on this essay, as it requires it's own essay.
A very interesting study was presented at the annual Heart Rhythm Society convention in 2014, from Adelaide Australia, called the "Aggressive Risk Factor Reduction Study: Implications for AF (ARREST-AF)"
They hypo thesized that the late recurrence of atrial fibrillation after ablation is due to progression of pathology of the underlying atrial environment, and that aggressive risk factor intervention would improve ablation outcomes.
Therefore they asked patients if they would like to participate in a more intensive post- procedure program, or just receive the usual advice about "eat better and exercise more"!
The active treatment group participated in an intense lifestyle modification program in a dedicated clinic with doctors, and nurses, guiding them on diet, exercise, weight management, sleep apnea management, cholesterol and blood pressure treatment, smoking cessation and alcohol reduction: ALL THE USUAL STUFF WE ALL KNOW ABOUT AND DON"T DO!!!!
After the first ablation 61 accepted, and 88 refused and the follow-up was for 2 years.
Here's the difference:
After 1 year, 62% of those who participated were free of atrial fibrillation after a single ablation, and only 26% of the non-participating group were free of atrial fibrillation.
For those who then went on to have an additional ablation, 87% of the participating group were free of atrial fibrillation, whereas 48% of the non-participating group were free of atrial fibrillation. All of this achieved a high degree of statistical significance.
Additionally, those who participated in the risk factor medication arm had statistically significant improvements in blood sugar control, cholesterol levels, blood pressure with reduction in medications, sleep apnea, and an overall global improvement in well-being.
To conclude, I would suggest that atrial fibrillation, like so many health conditions, can be well managed with a variety of treatment options. The task at hand is to assess and work with one person at a time and treat each patient as a unique individual. Personal responsibility also plays a role! Yes you can take this or that medication for slowing the rate, or maintaining normal rhythm, or you can go to the electrophysiology lab and have an ablation, which may or may not work, but the underpinning is to try and live a healthy life with a healthy attitude and do yourself what is right as regards nutrition, good sleep, good activity, less alcohol, stop smoking, and take the right medications to improve your cholesterol numbers and your blood pressure numbers...and by doing all of this, the problems of atrial fibrillation may indeed resolve.
I hope that you found the first part of my atrial fibrillation discussion helpful, as well as this second part. Obviously there is so much more that I could have included, but I did want to deliver an educational and pragmatic overview.