By Dr. Afroze Ahmad, Las Sendas Cardiology, PC
This is the second article in the four-article series on atrial fibrillation by Dr. Ahmad. The first article of the series appeared in the June edition of Up Close, and introduced the topic of atrial fibrillation. The remaining two articles in the four articles series will address treatment options for atrial fibrillation and the challenges with blood thinners, including Warfarin.
Nature wants the heart to beat in a certain rhythm, but, as discussed in the previous article, with atrial fibrillation, the synchrony or rhythm of the heart is lost.
There are many causes for atrial fibrillation. The risk rises with increasing age. Additionally, males are more prone to develop atrial fibrillation than women. The presence of underlying heart disease also increases the risk.
Most common heart-related causes for atrial fibrillation include long-standing high blood pressure, and coronary artery disease, which actually is the blockages in the coronary arteries. Heart failure and diabetes also are associated.
Certain diseases not related to the heart also may predispose to atrial fibrillation. These include snoring, kidney disease, obesity, and thyroid harmone malfunction. Interestingly, both overactive and/or underactive thyroid harmone may cause atrial fibrillation.
Atrial fibrillation also may occur in families and may be inherited. Alcohol also is a very common cause.
Similarly, atrial fibrillation may be related to medications. Bronchial asthma and chronic obstructive pulmonary disease (COPD) medications like theophylline, if used on a regular basis, may increase the risk. The jury is still out if drugs taken to treat osteoporosis, for example, may increase the propensity for atrial fibrillation.
The diagnosis starts with a detailed history of current symptoms. Alerting symptoms for atrial fibrillation include a history of palpitations, dizziness and/or lightheadedness. Many patients present with ankle swelling or shortness of breath. Chest pain with exertion also may occur. Sometimes, a sensation of the heart jumping out of the chest is the only presenting complaint.
Sleeping habits are addressed to elicit history of snorning. A comprehensive history of palpitations in family members, parents, siblings and cousins may unmask heriditary causes of atrial fibrillation. A meticulous drug history also may give pointers toward the causes. Alcohol intake, both quantity and frequency, also is addressed.
Evidence of COPD, swollen ankles, high blood pressure or an enlarged thyroid gland may point toward the cause of atrial fibrillation. Increased body index and weight measurements also may explain the propensity toward atrial fibrillation.
Malfunction of the thyroid may be seen on the blood test results. Low levels of certain salts in the body, including potassium and magnesium, may reveal the precipitating cause for atrial fibrillation
Atrial fibrillation per se is not a deadly rhythm. However, if sustained for long, it may pose serious problems. The complications fall under two categories, namely heart rate and blood clots.
The heart rate, if fast, leads to palpitations, chest pain and shortness of breath. If a fast heart rate is sustained for long periods, the heart may simply tire out. This may cause heart failure with ankle swelling and shortness of breath.
Similarly, a slow heart rate, with atrial fibrillation, may cause fatigue, lassitude or passing out.
Nature wants the blood to be squeezed out of the heart and pumped into the body with each heartbeat. With atrial fibrillation, the heart no longer squeezes adequately.
With atrial fibrillation, the heart merely fibrillates or quivers. When the heart quivers, the blood is not completely expelled from the heart. When it remains in the heart, it simply stagnates. A blood clot is formed by the stagnated blood in the heart.
The route and direction taken by the blood clot dictates the complication. This blood clot may break off and go to the brain, where it may cause a stroke. The same blood clot also may go to a limb, leading to loss of a limb. A clot to the eye may cause visual impairment, and a clot to the intestinal blood supply may cause severe abdominal pain, requiring surgery.
The rationale to treat atrial fibrillation is to avoid or minimize the risks of the the above mentioned complications.
Still, the most important message to take home is that atrial fibrillation is not a deadly rhythm.