The Link Between Atrial Fibrillation and Heart Health: Prevention and Management
Atrial fibrillation (AF) has a significant impact on the heart’s ability to serve its role as a regular and efficient pump which keeps us alive. Most people with AF will experience symptoms which can be incredibly disconcerting, including palpitations, a rapid, or skipped heart beat, shortness of breath, lightheadedness, or chest pain.
In the following article, you can learn more about how your heart health can impact your risk of AF, and conversely how AF can adversely impact your heart health and overall health, including its effect on dementia, lack of energy, heart attacks and heart failure.
What is Atrial Fibrillation?
Atrial fibrillation is a common heart rhythm disorder that occurs when the heart’s upper chambers (atria) beat highly irregularly and often faster than normal. Instead of the coordinated contractions that facilitate effective blood pumping, the atria fibrillate, which is equivalent to quivering (imagine a bag of worms moving continuously in an uncoordinated manner), and therefore minimizes the efficiency of the atrial contraction. This dramatically increases the risk of blood pooling and increases the risk of blood clots forming in the heart. If the clot from the heart dislodges and travels to the brain through circulation, then it can cause a stroke.
The Connection Between Atrial Fibrillation (AF) and Heart Health
Atrial Fibrillation and heart health are intricately linked. The irregular heartbeat associated with AF can reduce the heart’s pumping efficiency and gradually lead to dilatation of the heart’s chambers, which may eventually lead to valvular regurgitation (particularly functional mitral regurgitation).
This dilation and heart valve abnormality may cause progressive fatigue and shortness of breath in certain individuals, but the timing of onset of symptoms may be highly variable. It appears that some patients can tolerate a long period of AF without any obvious symptoms (i.e. asymptomatic AF), and others, particularly those patients who tend to run much higher heart rates throughout the day (for example <110bpm whilst resting), may succumb more rapidly to progressive highly symptomatic atrial fibrillation with fatigue, palpitations, and shortness of breath being the most dominant symptoms in this group of patients.
So why do some patients have high heart rates in AF and some don’t? In a nutshell, we don’t fully understand this. However, this is highly likely to be due to the autonomic nervous system. This is that bit of the primitive brain which controls all the automatic bodily functions and in particular, modulates a heart rate responsiveness to day-to-day activities.
For example patients with normal heart rhythms, we do expect to see with normal variation with day/night heart rates, with the ability of the heart rate to respond to instantaneous physical activity such as a sprint or a run, or even mental stress, such as preparing for an examination or interview, or indeed having an argument.
This aspect of heart rate control is governed by the sympathetic nervous system, which is part of the autonomic nervous system that governs the fright or flight response. Conversely while sleeping, the vagus nerve, which governs the parasympathetic nervous system or the rest and digest response, becomes dominant and the heart rate is typically much lower.
It may well be that in some patients with AF, there is some degree of autonomic dysregulation in which the autonomic nervous system is skewed towards the fright or flight response for most of the day and as a consequence, the heart rate profile of such patients remain elevated throughout the day. Typically as a cardiologist, I would want that the heart rate to be lower than 100 bpm on average and for the ideal profile, much lower than this and with heart rates not exceeding rates of 160 to 170 bpm for any length of time.
Coming back to the role of atrial fibrillation in modifying heart health, apart from causing the atrial dilatation and valvular regurgitation, atrial fibrillation itself makes the heart much less efficient pump, to the tune of 25%-40% less efficient than the heart functioning in normal rhythm. In some patients, this makes no difference whatsoever particularly in fit and healthy individuals who have a lot of “ cardiac reserve”, where a decline in the efficiency of the heart pump by up to 40%, does not appear to impact day-to-day living or cause any symptoms in patients.
These patients tend to have atrial fibrillation which are undiagnosed sometimes for several years and may be surprised to find the diagnosis during a routine health check or whilst being assessed for any other condition.
The most important consideration however with the diagnosis of atrial fibrillation is whether or not patients are at risk of having a stroke. Please read this for more information on this important aspect of AF management.
How do I diagnose Atrial Fibrillation?
However some patients are highly symptomatic with the dominant symptoms of fatigue, palpitations, shortness of breath, and in these patients, it is important to be aware of the average heart rates (your doctor may wish to arrange for your to have a diagnostic test, a 24-hour Holter monitor, a continuously running electrocardiogram (ECG) worn around your chest) to ascertain your average heart rate. If your heart rate is noted to be elevated throughout the 24-hour period you are likely to be prescribed a drug to lower your heart rate. Some consumer devices are very effective at taking single 30 second snapshot ECGs such as the AliveCor Kardia Mobile device or smart watches such as Apple, Samsung Gear or Withings ScanWatch with ECG recording capabilities – these products can typically show a trace which indicates AF, and may help your doctor achieve a diagnosis.
Note however, that most of these single snapshot devices will likely be inadequate for tracking heart rates over a long period of time (ie. 24 hours). However there are some consumer products which now track heart rate fairly over a continuous period – up to 48h fairly accurately and deliver close to an ECG quality tracings for your doctor to look at (https://uk.fourthfrontier.com).
So how does heart health impact AF?
We have read above how atrial fibrillation can impact aspects of heart health the converse is also true. To maintain freedom from atrial fibrillation, there are aspects in the heart health that should be attended to to minimise to risk of developing atrial fibrillation. The most common risk factors for developing atrial fibrillation include ischaemic heart disease, where the circulation in 1 or more of the arteries supplying the heart muscle tissue, is narrowed, potentially causing poor circulation (or ischaemia). Patients with heart attack have a much higher incidence of developing atrial fibrillation.
The other risk factors to monitor and control are hypertension, and diabetes which are major cardiovascular risk factors for overall heart health and which clearly also significantly increases the risk of developing atrial fibrillation. More than that, these very risk factors puts the patient at a much higher risk of stroke if atrial fibrillation is diagnosed.
Taken a step further, one of the the major risk factors for developing diabetes and hypertension is obesity particularly central obesity where bulk of the fat is centred around the belly/waistline. This visceral fat is particularly bad for metabolic health and as a consequence, puts patients at risk of developing cardiovascular risk factors including the hypertension, diabetes and in addition, high cholesterol levels, all of which can modify cardiovascular risk and promote overall narrowing in the arteries and development of atrial fibrillation.
Obesity also significantly increases the risk of obstructive sleep apnoea, a condition where the airway is obstructed many times overnight causing lack of refreshing sleep and importantly, frequent activations of the autonomic nervous system throughout the night, which is an important risk factor for developing atrial fibrillation. Therefore if you are obese, and if your family members or partner suggests that you snore loudly and sometimes stop breathing at night, it is definitely worth seeing a doctor to get some advice on whether you may have obstructive sleep apnoea.
What are the most effective prevention measures for atrial fibrillation?
1. Maintain a Healthy Lifestyle: A balanced diet rich in fruits, vegetables, whole grains, lean proteins, and healthy fats can contribute to heart health. Avoid excessive salt and sugar intake. Combined with regular exercise, which includes a combination of aerobic, flexibility, and strength training, this helps to maintain the ideal metabolic state and reduces the risk of developing conditions which may be associated with atrial fibrillation (hypertension, diabetes, sleep apnoea)
2. Monitor Blood Pressure: High blood pressure is a major risk factor for AF. Regular check-ups and adherence to prescribed medications can help manage blood pressure effectively. In view have hypertension, the top tips for reducing this include daily exercise, low-salt diet, weight loss, reduction in alcohol consumption, stress regulation strategies such as mindfulness, yoga, and breathing techniques, and if you are on medications, to have this reviewed regularly by your doctor.
4. Limit Alcohol and Caffeine: Excessive alcohol and caffeine consumption can trigger AF episodes. Some patients may have much clearer triggers, for example eating spicy or very salty foods and if this sounds like you, then clearly avoiding your specific triggers will be helpful in minimising episodes of atrial fibrillation
5. Quit Smoking: Smoking damages the heart, lungs and blood vessels, increasing the risk of heart-related conditions, including AF.
Managing Atrial Fibrillation
For a more comprehensive review on management of atrial fibrillation please see the following link (https://drboonlim.co.uk/atrial-fibrillation/)
However top tips of management of atrial fibrillation include:–
1. Medications: Doctors may prescribe medications to control heart rate, rhythm, and blood clot prevention. It’s crucial to take these medications as directed. In particular, if your doctor prescribes blood thinners (such as warfarin or a direct oral anticoagulant such as apixaban, rivaroxaban, edoxaban, or dabigatran), then this is something that you should continue taking without missing a dose, as its crucially important in minimising your stroke risk.
2. Cardioversion: This procedure involves restoring a normal heart rhythm using an electric shock (termed a direct current cardioversion or DCCV) or medications (such as amiodarone or flecainide). Occasionally your doctor may choose to combine both medications and a cardioversion after commencing the medication for 6 weeks to maximise the chances of successful cardioversion .this strategy is often used for short-term AF episodes.
3. Ablation: In this procedure, a cardiac electrophysiologist, a specialist cardiologist operates using keyhole surgical techniques to cauterise or freeze areas in the heart that are responsible for driving and maintaining atrial fibrillation. Its important to see a cardiologist who has experience in management of AF, including being highly adept at using the emerging technologies used to treat atrial fibrillation. See https://drboonlim.co.uk/best-cardiologist-to-treat-atrial-fibrillation/
5. Blood Thinners: People with AFib are at an increased risk of blood clots. Blood-thinning medications can help reduce this risk.
Understanding the link between atrial fibrillation and heart health is essential for preventing and managing this condition. By making healthy lifestyle choices, monitoring blood pressure, managing stress, and following medical advice, individuals can take proactive steps to protect their heart and overall well-being. If you suspect you have AF or are at risk, consult a healthcare professional for proper evaluation and guidance.