“Sodium plays a key role in your body. It helps maintain normal blood pressure, supports the work of your nerves and muscles, and regulates your body’s fluid balance.”

MAYO CLINIC

Hyponatremia is a condition that occurs when the level of sodium in your blood is abnormally low. Sodium is an electrolyte, and it helps regulate the amount of water that’s in and around your cells.

In hyponatremia, one or more factors — ranging from an underlying medical condition to drinking too much water during endurance sports causes the sodium in your body to become diluted. When this happens, your body’s water levels rise, and your cells begin to swell. This swelling can cause many health problems, from mild to life-threatening.

Hyponatremia treatment is aimed at resolving the underlying condition. Depending on the cause of hyponatremia, you may simply need to cut back on how much you drink. In other cases of hyponatremia, you may need intravenous fluids and medications.

Sodium we know what systems it effects from yesterday’s article on sodium in general of how it works in the human body.  If you don’t know and didn’t get a chance to read it yesterday stop this article going to yesterday’s to read over the general information of how sodium works and effects the human body.  This will help you understand the signs and symptoms easier.

Hyponatremia signs and symptoms may include:

• Nausea and vomiting
• Headache
• Confusion
• Loss of energy and fatigue
• Restlessness and irritability
• Muscle weakness, spasms or cramps
• Seizures
• All the way to a ComaA normal sodium level is between 135 and 145 milliequivalents per liter (mEq/L) of sodium. Hyponatremia occurs when the sodium in your blood falls below 135 mEq/L.
• Many possible conditions and lifestyle factors can lead to hyponatremia, including:
• Sodium plays a key role in your body. It helps maintain normal blood pressure, supports the work of your nerves and muscles, and regulates your body’s fluid balance playing a particular role in acid and base balances inside our blood stream working with in particular potassium.

• Certain medications. Some medications, such as some water pills (diuretics), antidepressants and pain medications, can cause you to urinate or perspire more than normal.  Medications that increase your risk of hyponatremia include thiazide diuretics as well as some antidepressants and pain medications. In addition to the recreational drug Ecstasy has been linked to fatal cases of hyponatremia.
• Heart, kidney and liver problems. Congestive heart failure and certain diseases affecting the kidneys or liver can cause fluids to accumulate in your body, which dilutes the sodium in your body, lowering the overall level.
• Syndrome of inappropriate anti-diuretic hormone (SIADH). In this condition, high levels of the anti-diuretic hormone (ADH) are produced, causing your body to retain water instead of excreting it normally in your urine.
• Chronic, severe vomiting or diarrhea. This causes your body to lose fluids and electrolytes, such as sodium.
• Drinking too much water. Because you lose sodium through sweat, drinking too much water during endurance activities, such as marathons and triathlons, can dilute the sodium content of your blood. Drinking too much water at other times can also cause low sodium.
• Dehydration. Taking in too little fluid can also be a problem. If you get dehydrated, your body loses fluids and electrolytes.
• Hormonal changes. Adrenal gland insufficiency (Addison’s disease) affects your adrenal glands’ ability to produce hormones that help maintain your body’s balance of sodium, potassium and water. Low levels of thyroid hormone also can cause a low blood-sodium level.
• The recreational drug Ecstasy. This amphetamine increases the risk of severe and even fatal cases of hyponatremia. In acute hyponatremia, sodium levels drop rapidly — resulting in potentially dangerous effects, such as rapid brain swelling, which can result in coma and death.Seek emergency care for anyone who develops severe signs and symptoms of hyponatremia, such as nausea and vomiting, confusion, seizures, or lost consciousness.
• Call your doctor if you know you are at risk of hyponatremia and are experiencing nausea, headache, cramping or weakness. Depending on the extent and duration of these signs and symptoms, your doctor may recommend seeking immediate medical care.
• Premenopausal women appear to be at the greatest risk of hyponatremia-related brain damage. This may be related to the effect of women’s sex hormones on the body’s ability to balance sodium levels.
• In chronic hyponatremia, sodium levels drop gradually over 48 hours or longer — and symptoms and complications are typically more moderate.
• Also for older adults they may have more contributing factors for hyponatremia, including age-related changes, taking certain medications and a greater likelihood of developing a chronic disease that alters the body’s sodium balance.

“If you suspect that someone has had a brain injury, the first step is to talk with the person, share your observations, and encourage the person to get help. The next step is for the person to share a medical, family and military history with the physician.”

Harvey E. Jacobs, Ph.D. and Flora Hammond, M.D

If you could split the brain right down the middle into two symmetrical, or equal parts, you would have a right and left hemisphere. Although equal in size, these two sides are not the same, and do not carry out the same functions.

Robert W. Sperry (awarded the Nobel Prize in 1981. While studying the effects of epilepsy)

“The brain stem controls the flow of messages between the brain and the rest of the body.”

MedicineNet.com (http://www.medicinenet.com/script/main/art.asp?articlekey=2517)

“The brain is a soft mass of supportive tissues and nerves connected to the spinal cord. Some of the nerves in the brain go right to the eyes, ears and other parts of the head. Other nerves connect the brain with other parts of the body through the spinal cord to control personality, senses and body functions from breathing to walking.”

Neurology and Neuro Surgery of John Hopkins Medicine http://www.hopkinsmedicine.org/neurology_neurosurgery/centers_clinics/brain_tumor/about-brain-tumors/how-the-brain-works.html

“Catheter ablation for SVT utilizing radiofrequency ablation (electrocautery injury) was developed in the 1980’s and has since revolutionized the treatment of SVT.”

UNC Healthcare (Center for vascular and heart care)

TREATMENT APPROACHES

The long, flat line between impulses indicates an abnormally slow heartbeat.

In some cases, arrhythmias may not require treatment. Other arrhythmias can be controlled by treating the underlying cause. Arrhythmias that cause symptoms may require one or more of the following treatments to reduce the number or duration of arrhythmic events.

Medications. Common medications for suppressing arrhythmias include:

• Beta-blockers;
• Calcium channel blockers;
• Digitalis; and
• Antiarrhythmic agents.

Digitalis should not be used for certain arrhythmias, such as WPW syndrome. People with atrial fibrillation are typically prescribed an anticoagulant to minimize their risk of clotting and stroke.

Cardioversion. This procedure restores a normal heartbeat by transmitting a brief electric shock through the chest to the heart. Usually an outpatient procedure that is performed in a hospital while the patient is under heavy sedation or anesthesia, it is commonly used to treat:

• Atrial fibrillation;
• Atrial flutter; and
• Ventricular arrhythmias.

Radiofrequency Catheter ablation. A catheter with an electrode tip is positioned on the affected area. The catheter delivers energy to destroy tissue that is interfering with the normal transmission of electrical impulses through the heart. It is most commonly used for:

• SVT – Supra Ventricular Tachycardia (Pulse over 100);
• Atrial fibrillation-particularly newly diagnosed;
• Atrial flutter; and
• Certain types of ventricular arrhythmias.

Catheter ablation for SVT utilizing radiofrequency ablation (electrocautery injury) was developed in the 1980’s and has since revolutionized the treatment of SVT. With catheter ablation, a procedure is performed entirely through intravenous catheters inserted into the veins in the leg and sometime the shoulder. It is a minimally invasive procedure. That is, no open heart surgery is needed. Generally, procedures can be performed on an outpatient basis. Overall cure rates with catheter ablation is >90% and can be as high as 96-98% depending on the specific type of SVT.

During a catheter ablation procedure, catheters (long wire electrodes) are advanced through the veins in the leg up to the heart.

Various measurements of the electrical system are performed. If a person is in normal rhythm at the time of the procedure, an attempt is made then to reproduce the SVT by pacing the heart through the catheters. Occasionally an intravenous medicine called isoproterenol is required to “rev up” the heart in order to reproduce the SVT. Once the SVT is reproduced, the specific type of SVT can be diagnosed using the catheters in the heart.

Once the SVT is diagnosed, to cure the SVT, an ablation catheter is advanced to the heart. An ablation catheter is capable of delivering small radiofrequency lesions (electrocautery burns) on the order of 4-5 mm in diameter. These radiofrequency lesions have no long-term adverse consequences. Depending on the type of SVT, these radiofrequency lesions are delivered in various locations of the heart.

Occasionally, more complex diagnostic and ablation techniques are required for catheter ablation of SVT. This may be the case particularly in patients with other heart problems or a history of heart surgery. In such situations, sophisticated 3-dimensional mapping techniques using a balloon catheter may be used to identify the location necessary to successful ablate the SVT

Pacemaker. A small electronic device that is surgically implanted under the skin near the collarbone. A pacemaker regulates a slow or erratic heartbeat by sending rhythmic electrical charges to the right atrium and right ventricle. Pacemakers are frequently used to treat Sick Sinus Syndrome.

Maze procedure. A physician makes multiple incisions through the atrium. The resulting scar tissue conducts impulses through the heart’s electrical system in a way that allows normal conduction but does not sustain atrial fibrillation. Since it is a form of cardiac surgery, it is reserved for those patients who have undergone a failed catheter ablation or as an add-on for those having a surgical procedure for another condition.

Cardiac arrhythmia, also known as cardiac dysrhythmia or irregular heartbeat, is a group of conditions in which the heartbeat is irregular, too fast, or too slow.

Susheel K. Kodali, MD is the co-director of the Heart Valve Center at NewYork-Presbyterian/ Columbia University Medical Center.

Ablation is used to treat abnormal heart rhythms, or arrhythmias. The type of arrhythmia and the presence of other heart disease will determine whether ablation can be performed surgically or non-surgically.

Ablation therapy using radio frequency waves on the heart is used to cure a variety of cardiac arrhythmiae such as supraventricular tachycardia, Wolff–Parkinson–White syndrome (WPW), ventricular tachycardia, and more recently as management of atrial fibrillation (especially when its newly diagnosed when medical management can’t change it back to normal sinus rhythm, which is the normal cardiac rhythm seen on a telemetry monitor or of an EKG taken on a patient).

An arrhythmia is a change in the heart’s normal rate or rhythm, normally between 60 and 100 beats per minute. Arrhythmias are classified by their location in the heart and by their speed or rhythm. An atrial arrhythmia is an abnormality that occurs in one of the two upper chambers of the heart, the left or right atrium. Arrhythmias are associated with aging and typically happen more frequently during middle age. At least 10 to 15 percent of people older than 70 years experience arrhythmias.  We have what we call our human pacemaker of the heart that naturally sends conduction for the heart to pump, which is called the sinus node.  This is in the upper left corner of the right chamber of the heart.  That is where the name sinus rhythm derives from (the sinus node) which is the best rhythm a human can be in as long as the pulse rate stays above 60 and stays under 100. Now if that sinus node for some reason breaks down and no longer works; so than the pace site starts somewhere in the right atrium below the sinus node (the heart is compensating for whatever is the reason the sinus node is not working).  So now the rhythms are called atrial rhythms because of where the new natural pacemaker site is in the heart.  This is where ablation comes into play if the type of atrial rhythm they have is detrimental to the patient; including if that patient is a candidate for this procedure.  Between our heart chambers on the top (called atriums) and below (called the ventricles) is a AV (meaning atrioventricular valve).  Rhythms above the ventricles are also grouped as supraventricular rhythms.  Which is what ablation is used for.

Types of rhythms a patient would be considered for ablation as a possible treatment:

Atrial fibrillation. The electrical signal that circles uncoordinated through the muscles of the atria (the upper chambers of the heart), causing them to quiver (sometimes more than 400 times per minute) without contracting. The ventricles (the lower chambers of the heart) do not receive regular impulses and contract out of rhythm, and the heartbeat becomes uncontrolled and irregular. It is the most common atrial arrhythmia, and 85 percent of people who experience it are older than 65 years.

Atrial fibrillation can cause a blood clot to form, which can enter the bloodstream and trigger a stroke. Underlying heart disease or hypertension increases the risk of stroke from atrial fibrillation as does age even without heart disease or hypertension.

Premature atrial contraction (PAC or premature atrial impulses). A common and benign arrhythmia, a PAC is a heartbeat that originates away from the sinus node, which sends electrical signals through the upper chamber. It typically occurs after the sinus node has initiated one heartbeat and before the next regular sinus discharge. A PAC can cause a feeling of a skipped heartbeat. Use of caffeine, tobacco, and/or alcohol, or stress can bring on PACs or increase their frequency.

Supraventricular tachycardia (SVT). Characterized by a rapid heart rate that ranges between 100 and 240 beats per minute, SVT usually begins and ends suddenly. SVT occurs when an electrical impulse ‘re-enters’ the atrial muscles. A disorder that a person may have at birth, SVT is commonly caused by a variation in the electrical system of the heart. SVT often begins in childhood or adolescence and can be triggered by exercise, alcohol, or caffeine. SVT is rarely dangerous, but can cause a drop in blood pressure, causing lightheadedness or near-fainting episodes, and, rarely, fainting episodes.

Atrial flutter. Differentiated from atrial fibrillation by its coordinated, regular pattern, atrial flutter is a coordinated rapid beating of the atria. Most who experience atrial flutter are 60 years and older and have some heart disorder, such as heart valve problems or a thickening of the heart muscle. Atrial flutter is classified into two types, according to the pathways responsible for it. Type I normally causes the heart rate to increase to and remain at 150 beats per minute. Rarely, the rate may reach 300 beats per minute; sometimes it decreases to 75 beats per minute. Type II increases the atrial rate faster, so the ventricular rate may be 160 to 170 beats per minute. As with atrial fibrillation, atrial flutter increases the risk of stroke.

Sick sinus syndrome (SSS). Common among older people, SSS is an improper firing of electrical impulses caused by disease or scarring in the sinus or Sinoatrial node (SA node). SSS normally causes the heart rate to slow, but sometimes it alternates between abnormally slow and fast. A progressive condition, with episodes increasing in frequency and duration, SSS can be caused by:

• Degeneration of the heart’s electrical system; or
• Diseases of the atrial muscle.

Sinus tachycardia. The sinus node emits abnormally fast electrical signals, which increases the heart rate to between 100 beats per minute to 140 beats per minute at rest, and 200 beats per minute during exercise. A normal response to exercise or stress, it can also be caused by:

• Adrenaline;
• Consumption of caffeine, nicotine, or alcohol; and
• Heart conditions.

Sinus bradycardia. Associated with impaired impulse generation in the SA node, it causes the heart rate to decrease to fewer than 60 beats per minute. Commonly caused by SSS, drugs like beta-blockers and calcium-channel blockers can also cause sinus bradycardia. Occasionally sinus bradycardia can be caused by impaired conduction of impulses to the atrial muscles.

Wolff-Parkinson-White syndrome (WPW). WPW syndrome occurs when electrical signals fail to pause in the atrioventricular node because an extra pathway allows the impulse to “bypass” the normal pathway; and the syndrome is sometimes called bypass tract. WPW syndrome causes heart rates approaching 240 beats per minute.

Occasionally, impulses can go down one extra pathway and up another, creating a “loop” or “short circuit,” (called SVT because of WPW). Patients with WPW syndrome may develop atrial fibrillation and are at increased risk for developing a dangerous ventricular arrhythmia when this occurs.

CAUSES AND RISK FACTORS

Problems with the heart’s electrical system or with the muscles’ response to the signal can cause arrhythmias. Physicians have categorized arrhythmias to their type:

• Disorders of impulse generation – A signal that generates part of the heart’s electrical system other than the SA node.
• Disorders of impulse conduction – “block” the heart’s electrical impulse and prevent it from traveling its normal pathway.
• Heart attack – causes scarring of the heart, which can interrupt electrical impulses.

People without heart disease can develop an arrhythmia for unknown causes, but risk factors can include:

• Emotional stress;
• Consumption of alcohol, caffeine, diet pills, and tobacco; and
• Some prescription medications (certain heart drugs and certain cold, cough, allergy medications and anti-depressants).

WHAT ARE THE SYMPTOMS?

The onset and duration of arrhythmia symptoms vary according to its type, frequency, duration, and whether structural heart disease is present.

Common symptoms that people experience may include:

• Palpitations (the sensation of skipped heartbeats);
• Lightheadedness;
• Shortness of breath;
• Fatigue;
• Chest pain;
• Fainting; and
• Urge to urinate.

Certain arrhythmias may cause fainting, and, occasionally stroke, while others (‘silent’ arrhythmias) cause no symptoms.

DIAGNOSIS

Arrhythmias can be difficult to diagnose because they can be unpredictable and brief. A physician will typically take a person’s medical history, and perform a physical examination, during which the physician may detect an arrhythmia using a stethoscope. Arrhythmias that occur infrequently, last for short periods of time, or do not cause noticeable symptoms may require more detailed tests, such as:

• Electrocardiogram (ECG);
• A Holter monitor (an ambulatory ECG); and/or
• A loop ECG.

Part 2 on Ablation tomorrow.