Archive for the ‘Heart Conditions’ Category

Atrial Fibrillation

Monday, March 8th, 2010

Atrial fibrillation is the most common cardiac arrhythmia, or abnormal heart rhythm seen today.

Approximately 2.2 million Americans suffer from this disorder. On average, there are 160,000 new cases of diagnosed each year. Atrial fibrillation is a disorder in which the upper two chambers of the heart no longer beat in a normal, synchronized fashion. Rather, electrical impulses move about both atria in a chaotic, or circus-movement pattern, resulting in activation of the atria at somewhere between 400 and 600 times per minute. The impulses coursing through the atria traverse through a structure called the A-V node to reach the ventricles. The hallmark of atrial fibrillation is an irregular rhythm where the ventricles, or bottom pumping chambers of the heart, beat in a very chaotic fashion.

What are the warning signs and symptoms of atrial fibrillation?
Individuals with atrial fibrillation may have heart rates that are too slow, too fast, or within the normal range. Individuals with atrial fibrillation may experience no symptoms, limited symptoms in the form of palpitations, or catastrophic symptoms such as loss of consciousness due to rates which are either too fast or too slow. A major risk of atrial fibrillation is stroke, with the incidence of stroke approximately five times that of similar-aged individuals who do not have atrial fibrillation. The risk factors which appear to increase the risk of stroke in individuals with atrial fibrillation include age greater than 65 years, presence of diabetes mellitus, presence of hypertensive heart disease, congestive heart failure, mitral stenosis (tight mitral valve), or history of prior stroke or near-stroke (Transient Ischemic Attack). The risk of stroke in individuals with atrial fibrillation may be significantly reduced by use of anticoagulant therapy in the form of Warfarin.

What are the treatment options for atrial fibrillation?
Treating atrial fibrillation varies by individual. Your doctor will take a thorough history and perform a comprehensive physical examination to determine if your atrial fibrillation is due to another problem, such as hypertension, coronary artery disease, valvular heart disease, or thyroid dysfunction. Oftentimes, the atrial fibrillation is resolved with the treatment of these primary problems.

If the atrial fibrillation is not corrected by resolution of the primary problem, the patient is oftentimes anti-coagulated for three to four weeks, and subsequently cardioverted back to normal rhythm. Cardioversion may occur in the form of an anti-arrhythmic medication either orally or intravenously, or by the administration of electric shock therapy through patches placed on the chest. Electrical cardioversion occurs in a hospital setting, with the patient under brief general anesthesia for two to three minutes. Following cardioversion, patients are frequently kept on anticoagulant therapy for a minimum of three to four weeks to prevent a stroke that may occur up to that period of time following cardioversion. At times, atrial fibrillation is allowed to persist, without an attempt at cardioversion. In that case, the main concern, aside from anticoagulation, is to control the rate of the ventricles, and is typically done with either medical therapy or with use of a pacemaker in combination with A-V Nodal Ablation (see below).

Other Treatment Options
At times, medications do not adequately control the ventricular rate in atrial fibrillation. In these cases, a commonly performed procedure today is to place a pacemaker, either single or dual-chamber, followed by catheter ablation of the A-V Node. While this does not abolish the atrial fibrillation itself, or the need for anticoagulant therapy, it does abolish the slow or rapid ventricular response that may occur, and allows the patient to have a regular, normalized heartbeat.

One of the newer procedures for atrial fibrillation involves placing catheters into the left atrium near the pulmonary veins, which are the vascular channels that drain blood returning from the lungs to the heart. Atrial fibrillation today is thought to originate from small islands of tissue within the pulmonary veins, and catheter-ablation at the entrance of the vein into the left atrium may prevent the atrial fibrillation from occurring.

Aortic Dissection

Monday, March 8th, 2010

Aortic dissection is a tear or partial tear in the lining of the largest blood vessel in the body, the aorta.

This tear allows blood (and the pressure of the blood flow) to penetrate the arterial wall. Over time, this continuous flow can cause the aorta to rupture–a condition that most people do not survive. There are two types of aortic dissections, although sometimes both conditions occur:

  • Type A: A dissection to the ascending aorta is classified as a Type A dissection. These dissections can be treated with interventional catheterization or open surgical techniques.
  • Type B: A dissection of the descending aorta is classified as a Type B dissection. These dissections are most often treated medically with routine monitoring and prescribed medications. There is a surgical option, but it carries substantially increased risk of paralysis.

What are the warning signs and symptoms of aortic dissection?
Aortic dissections are commonly found in people with atherosclerosis, high blood pressure, in individuals with a family history of aortic (or thoracic) dissection and are more rarely associated with congenital cardiovascular disorders (Marfan’s syndrome, Ehlers-Danlos syndrome, and congenital valvular disorders).

“Stabbing” pain in the back is a common symptom of an aortic dissection. In some cases, people present with pain in the chest. This pain may be confused with angina (commonly referred to as “chest pain” and a warning sign of a possible heart attack). The main difference between pain resulting from dissection of the aorta, and angina due to lack of blood supply to the heart muscle, is its sudden and intense onset. The pain is characterized as a “ripping” or “tearing” sensation. This sudden pain can be felt in the back, chest, neck, or jaw.

These are important differences to understand. Why? Because a common recommendation to those with angina or “chest pain” (that may result in a heart attack) is to chew an aspirin to thin the blood. This is NOT the case if you are experiencing an aortic dissection. Thinning the blood for a person with aortic dissection may cause more blood to leak out of the aorta. This internal bleeding can lead to death.

In some cases, people do not experience any pain. Instead, you may experience distorted mental capacity (due to lack of blood supply to the brain) or numbness or tingling sensation in the arms or legs (due to lack of blood supply to the spinal cord). If you or someone you know is experiencing any of the above symptoms, call 9-1-1 immediately to get to a hospital. The survival rate increases dramatically the sooner a person is treated for an aortic dissection.

How is an aortic dissection detected?
The key to diagnosing an aortic dissection is to confirm that it is in fact a dissection and not a heart attack, and which type it is (as the treatment options vary significantly).

The gold standard for diagnosing aortic dissection is a computed topography (CT) scan. Other imaging studies may be required to identify the type and location of the dissection. These include:

  • Echocardiogram
  • Magnetic Resonance Imaging (MRI)
  • Peripheral Angiography

What are the treatment options for an aortic dissection?
Three treatment options are offered for an aortic dissection: 1) medical management, 2) interventional catheterization, and 3) cardiovascular surgery. Depending upon the location and severity of the dissection, your physician will decide which option is best for you.

A small percent of cases (5 – 10%) are Type B dissections (dissections of the descending aorta). This condition can be treated with surgical repair, but it carries significant risk. Typically, your doctor will monitor the condition periodically and prescribe medications to control the dissection.

The techniques used to treat dissections are as follows:
Medical Therapy: Blood pressure and cholesterol lowering drugs, and treatment to reverse arteriosclerosis

Endovascular Intervention: This minimally invasive procedure requires small incisions in the groin. Small wire-like, catheter devices called endoluminal stent grafts are threaded to the location of the dissection. These devices have a woven synthetic graft tip, which is deployed at the site of dissection and left in place. This provides a channel for blood to flow freely, repairing arterial leakage, and preventing pressure from rupturing the aorta. This procedure is much less invasive than the traditional open surgery. Please note: This procedure can only be performed on specific patients based on clinical criteria, and no long-term data exists regarding its effectiveness compared to open surgery.

Open Surgical Repair: The traditional treatment technique involves opening the chest and surgically removing the dissected aorta. A synthetic graft is sewn in its place for blood to flow freely to the rest of the arterial system.

Aneurysm

Monday, March 8th, 2010

Aneurysms can occur in any blood vessel in the body, but the most common type arises in the largest artery in the body—the aorta. This condition affects over 200,000 Americans and is referred to as an Abdominal Aortic Aneurysm (AAA).

An aneurysm is a bulging of an artery caused by uncontrolled hypertension or injury or weakness to the artery itself. The pressure from blood flow against the arterial wall causes the aneurysm to slowly grow in size, giving it its bulging characteristic. Typically, atherosclerosis (plaque buildup within the arterial wall) is present.

An AAA is a very serious condition that claims the lives of 15,000 Americans every year. As the aneurysm continues to grow, it has the potential to rupture or leak. If this occurs, more than half of these individuals go into shock and die as a result of massive internal bleeding. The key is to detect an AAA at its earliest stage so it can be properly treated.

What are the warning signs and symptoms of an Aneurysm?
Abdominal Aortic Aneurysms (AAAs) are referred to as “the silent killer”, as the majority of people do not have symptoms. However, AAA can sometimes present with the following:

  • AAA’s are most common in people over the age of 60
  • 70% to 80% of AAA’s are in males; however, as more women are diagnosed with cardiovascular disease, this statistic is changing
  • High blood pressure, smoking, and high cholesterol levels have all been shown to increase the risk of developing an Abdominal Artic Aneurysm.
  • 20% of people with AAA’s have a family history of either cardiovascular disease or aneurysms

If you have one or more of the above risk factors, we recommend that you discuss with your doctor certain tests that can detect an AAA early so it may be properly treated.

Sometimes, people will experience these symptoms that suggest the presence of AAA:

  • Pain in the abdomen, back, or flank (side)
  • An overwhelming feeling of “fullness” after eating even a small amount of food
  • Frequent nausea and vomiting
  • Pulsating in the abdomen—for example, when reading a book that is resting on the abdomen, the book moves up and down

If you experience any of the above symptoms, you should be evaluated by a doctor immediately. Prompt action may prevent a life-threatening situation.

How is an Aneurysm detected?
Abdominal Aortic Aneurysms are sometimes detected during a routine physical examination. Your physician may hear pulsations in your abdomen (also called bruits) with a stethoscope. However, they are usually difficult to detect (especially in persons who are overweight). If your physician suspects that you may have an aneurysm, either due to pulsations in the abdomen or other risk factors such as family history, high blood pressure, high cholesterol, old age, etc., he or she will likely perform any of the following imaging studies to make the diagnosis:

  • Doppler Ultrasound
  • Chest or abdominal X-Ray
  • CT Scan
  • Magnetic Resonance Imaging (MRI)

What are the treatment options for an Aneurysm?
Once an Aneurysm (including AAA) is diagnosed, your physician will determine the appropriate treatment depending upon its size and location. If the Aneurysm is small, your physician will likely monitor its growth with repeated ultrasound imaging. If it is large (greater than 5 centimeters), or is growing rapidly and showing signs that it might rupture, an interventional catheterization or surgery may be required.