Are You Affected by Atrial Fibrillation (Afib)?

[Dr Alain L Fymat]

Are you Affected by Atrial Fibrillation (Afib)?

Atrial fibrillation (Afib) continues to baffle those affected by it. To be able to answer some of the questions these patients raise, it may be helpful to place them in the proper medical/clinical context by describing our current understanding of Afib, its diagnosis, and treatment.

What is Afib?

Afib is a most common abnormal heart rhythm. It is often associated with palpitations, fainting, chest pain, or congestive heart failure... although at times it may show none of these symptoms. It may occur in episodes lasting from minutes to days or even be permanent. We do not know its cause, but we understand its mechanism. Clinically, Afib may be identified when taking a pulse to be subsequently confirmed with an electrocardiogram (ECG).

What are the associated risks?

There are several risks associated with Afib, particularly an increased risk of stroke (can be up to a factor of five) depending on the presence of additional risk factors, especially high blood pressure. Further, chronic Afib leads to a small increase in the risk of death.

How is it diagnosed?

The ECG will usually show two things: the absence of what are called P-waves and an irregular ventricular rate. (Note that mere blood tests will not evidence Afib; that is not their purpose for they will only determine if the blood components fall within or exceed what are considered to be guideline ranges at that time period.) .

What are the treatment options?

Afib is often treated with medications to either (1) slow the heart rate (so-called "rate control") to a normal range or (2) correct the heart rhythm to a normal sinus rhythm (called "rhythm control"). One can also control the rhythm by converting Afib to a normal heart rhythm by (3) a technique called "electrical cardioversion" or (4) a surgical, catheter-based ablation or else (5) an implanted pacemaker. Obviously, the last three approaches are of last resort. This leaves medication such as baby aspirin, which is preferable to a poison like warfarin.

Depending on the risk of stroke and the formation of blood clots (which may migrate to other locations), anti-clotting medication may be used (such as, Warfarin known by the brand names: Coumadin, Jantoven, Marevan, Uniwarfin). These medications substantially reduce these risks but, unfortunately, may also increase the risk of major bleeding, mainly in older patients.

The following approach is suggested:

1. First ascertain the correct diagnosis and not a related or unrelated heart condition;

2. Depending on the ECG and other tests, ascertain the severity of Afib if that is the case in order to determine how aggressive the treatment should be;

3. Gradually start with baby aspirin perhaps every other day rather than every day and increase the dose depending on the results; and

4. Do not leave Afib (if that is the correct diagnosis) untreated especially with advancing age because of the increased risk of stroke, particularly in the presence of high blood pressure, and even a small increased risk of death.

NOTES:

1. Warfarin is commonly but incorrectly referred to as a blood thinner. Note that using this medication or any blood thinner (including baby aspirin) will only show the relative efficacy of these medications at controlling certain blood components, not their efficacy at controlling Afib.

2. Warfarin was introduced in 1948 as a pesticide against rats and mice and is still used for this purpose, although more potent poisons have been developed. It has been approved as a medication in 1954 and is currently the most widely prescribed oral anticoagulant drug in North America.

3. Despite its effectiveness, Warfarin has several shortcomings including: it interacts with many commonly used medications as do some foods (particularly leafy vegetable foods or "greens" since they typically contain large amounts of vitamin K1; and its activity must be monitored by blood testing to prevent overdosing.

4. Coumadin is indeed the “standard of care” for Afib and most, if not all, doctors will prescribe it lest they expose themselves to medical malpractice, demotion, or both.

Is there a role for vitamin E supplementation?

Vitamin E supplementation has been recommended in cardiovascular disease (CVD). CVD is the general name for diseases affecting the heart and blood vessels whereas coronary heart disease (CHD) is for diseases that affect the heart and coronary blood vessels. Common types of CVDs include thrombosis, angina pectoris, myocardial infraction (MI, commonly referred to as heart attack) and stroke. The main processes involved in both CVD and CHD are atherosclerosis and hypertension.

Atherosclerosis is the build-up of fatty “plaques” on the interior of the arterial lumen. The fatty substance is cholesterol, essentially its low density lipoprotein (LDL) component. LDL can be oxidated to lead to several undesirable effects (increased productions of inflammatory cytokines, tissue factors, macrophages and monocytes). Since vitamin E is a very potent fat-soluble antioxidant, it can inhibit the oxidation of LDL and thereby aid in protecting against atherosclerosis and stabilizing the existing plaques. Under this logic, there could be a valuable role in the treatment of Afib. However, the results of randomized controlled clinical trials have been controversial.

What are the latest clinical trial results?

1. From the Cleveland Clinic: Marc Gillinov, MD, and his colleagues found that adding surgical ablation of Afib during mitral valve surgery durably relieved the arrhythmia for about two-thirds of his patients but also increased the likelihood of requiring a pacemaker.

2. From the Montefiore Medical Center in New York City: Luigi di Biase, MD, PhD, and his colleagues reported that, compared with treatment with Amiodarone*, catheter ablation of persistent Afib in patients with congestive heart failure (CHF) reduced arrhythmia recurrence and also reduced hospitalization rates and mortality. (*Amiodarone is a class III anti-arrhythmic agent used for various types of cardiac disrhythmias, both ventricular and atrial. It was discovered in 1961. Despite relatively common side effects, it is used in arrhythmias that are otherwise difficult to treat with medication.)

3. From the Australia's Royal Adelaide Hospital: In a study involving 355 patients who had Afib with a body mass index of 27 kg/m², Rajeev K. Pathak, MBBS, and his colleagues reported that, like in coronary disease, freedom from Afib starts with lifestyle changes. Thus, people who lost at least 10% of body weight were six times more likely to be free from arrhythmia without anti-arrhythmic medication at 5 years. These results may be partially offset for people whose weight fluctuated by more than 5% during the clinical study. Freedom from Afib regardless of medication use was 85% if the weight is kept off with less that 2% weight fluctuation compared with 59% among those whose weight shifted around in the 2%-5% of body weight range and 44% among those who fluctuated even more.