HEART TO HEART

CARDIAC NEUROSIS

2011-11-05T14:59:00.000+05:30

Da Costa Syndrome or Cardiac neurosis is a condition in which cardiovascular symptoms are caused by physical or emotional stress but may also be caused by conditions such as mitral valve prolapse and autonomic hyperactivity. The syndrome is often seen in soldiers during times of stress or in young adults who suffer emotional stress.

Cardiac neurosis is an anxiety reaction characterized by quick fatigue, shortness of breath, rapid heartbeat, dizziness, and other cardiac symptoms, but not caused by disease of the heart. Some people complain of pain over the heart, or the heart area, who do not have the slightest sign of any real disturbance of the heart.

Doctors call this a cardiac neurosis, and credit it to abnormal anxiety about the heart. Such pains are not related to effort or work of the heart. They are usually accentuated by fatigue and emotional stresses. There various drug treatments available for this condition. But Systematic desensitization, a type of behavioural therapy, may be more effective than drugs, especially if it includes encouragement, instruction, and suggestion.

Systemic Desensitisation: In this procedure, events which cause anxiety are recalled in imagination, and then a relaxation technique is used to dissipate the anxiety. With sufficient repetition through practice, the imagined event loses its anxiety-provoking power. At the end of training, when you actually face the real event, you will find that it too, just like the imagined event, has lost its power to make you anxious.
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BLOOD PRESSURE ON STANDING

2011-11-05T14:54:00.000+05:30

Understanding How The Nervous System Regulates Blood Pressure :

Our blood pressure is regulated from minute to minute by nerves. At specific locations in the walls of the large arteries, special sensors "measure" blood pressure by responding to the amount of stretch in the walls of the arteries. An important location of these sensors is the carotid sinus, which is in the arteries that run up the neck to supply the head with blood.

When you suddenly sit or stand up after lying down. Gravity pulls the blood downward, lowering the blood pressure in the carotid sinus in your neck. If the carotid sinus reflex didn't act promptly, sending out nerve impulses (over sympathetic nerves) to increase heart output and constrict the arterioles, you would faint from the decreased flow of blood to your head.

Located along portions of the carotid artery and the aorta are several hundred pressure detectors called baroreceptors. These specialized cells operate like ‘stretch’ detectors that respond to alterations in blood pressure in the arteries and send neural signals to the brainstem to inform the brain which component of the autonomic nervous system should fire. Inadequate blood pressure should result in a signal to increase either heart rate or vasoconstriction via the sympathetic nervous system.

# Your blood pressure changes when you change position.

# When your heart contracts, it pushes blood into the arteries causing an increase in blood pressure (systolic pressure). When your heart relaxes and refills with blood, the pressure in the arteries decreases (diastolic pressure).

# Standing causes 500 to 700 ml of blood to pool in the legs, so there is less blood for the heart to pump. This results in a decrease in blood pressure.

# Special cells called baroreceptors (located close to the neck arteries) sense this decrease in blood pressure. They counteract by triggering the heart to beat faster and pump more blood in order to stabilize the blood pressure.
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CAUSES OF STROKE

2011-11-05T14:51:00.000+05:30

A stroke occurs when there's a problem with the amount of blood in your brain. The cause of the main type of stroke — ischemic stroke — is too little blood in the brain. The cause of the other type of stroke — hemorrhagic stroke — is too much blood within the skull.

1) Ischemic stroke:

About 80 percent of strokes are ischemic strokes. They occur when the arteries to your brain are narrowed or blocked, causing severely reduced blood flow (ischemia).

a) Thrombotic stroke. This type of stroke occurs when a blood clot (thrombus) forms in one of the arteries that supply blood to your brain. A clot usually forms in areas damaged by atherosclerosis.

b) Embolic stroke.
An embolic stroke occurs when a blood clot or other particle forms in a blood vessel away from your brain — commonly in your heart — and is swept through your bloodstream to lodge in narrower brain arteries. This type of blood clot is called an embolus. It's often caused by irregular beating in the heart's two upper chambers (atrial fibrillation). This abnormal heart rhythm can lead to poor blood flow and the formation of a blood clot.

2) Hemorrhagic stroke

"Hemorrhage" is the medical word for bleeding. Hemorrhagic stroke occurs when a blood vessel in your brain leaks or ruptures.

a) Intracerebral hemorrhage: In this type of stroke, a blood vessel in the brain bursts and spills into the surrounding brain tissue, damaging cells.

b) Subarachnoid hemorrhage. In this type of stroke, bleeding starts in a large artery on or near the surface of the brain and spills into the space between the surfaces of your brain and your skull.
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B P AFTER EXERCISE

2011-11-05T14:49:00.001+05:30

Normally, blood pressure increases from resting level with exercise. Based on criteria used for exercise treadmill tests, any decrease in blood pressure during exercise might be a sign of heart disease. The same is true, to a lesser extent, if there is a failure of the blood pressure to increase with exercise.

Once exercise has stopped, blood pressure should return to resting levels and may even drop to slightly below pre-exercise levels for a while based on a number of factors, like any medications one might be taking, overall fitness level, and the type and duration of exercise.

The whole question of what your fall in blood pressure really means depends on its timing. If it occurs during exercise or soon after stopping, talk to your doctor about having some sort of stress test (an exercise treadmill test or a stress echocardiogram), because, even though you feel well, this could be a warning sign of early heart disease. It may not be, but the exercise testing will help sort this out.

If you have any risk factors for heart disease (smoking, high blood pressure, diabetes, high blood cholesterol levels, or close relatives with heart disease before age 45), then a treadmill test might be an even better idea.
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ANTI-OXIDANTS

2011-11-05T13:59:00.000+05:30

Antioxidants are substances that may protect your cells against the effects of free radicals. Free radicals are molecules produced when your body breaks down food, or by environmental exposures like tobacco smoke and radiation. Free radicals can damage cells, and may play a role in heart disease, cancer and other diseases.

Antioxidant substances include

* Beta-carotene
* Lutein
* Lycopene
* Selenium
* Vitamin A
* Vitamin C
* Vitamin E

Antioxidants are found in many foods. These include fruits and vegetables, nuts, grains, and some meats, poultry and fish.

NOTE:

Oxidation of low-density lipoprotein (LDL or "bad") cholesterol is important in the development of fatty buildups in the arteries. This process, called atherosclerosis, can lead to heart attacks and strokes. Until recently, it was thought that LDL cholesterol lipoprotein oxidation and its biological effects could be prevented by using antioxidant supplements. However, more recent clinical trials have failed to demonstrate a beneficial effect of antioxidant supplements.

DETECTING HEART DEFECTS BEFORE BIRTH

2011-11-05T13:51:00.000+05:30

A heart defect can be detected in your baby using an ultrasound study or echocardiography, which is the name used for a specialized cardiac ultrasound. Diagnosis of a serious heart defect before your baby is born enables doctors to further examine the defect, closely monitor your child's overall health, carefully plan for your baby's delivery and ensure a smooth transition to the necessary specialized care after birth. In some cases, your baby may be a candidate for in utero treatment.

The common practice is for heart defects to be detected between 16 and 22 weeks. This is the usual age at which most pregnant women undergo a screening obstetric ultrasound. Some serious heart defects can be detected as early as 14 weeks.

Fetal ultrasounds are performed in most pregnant women to monitor fetal growth and to detect abnormalities. Serious congenital heart defects can be found during routine fetal ultrasounds. If your baby has potential risk factors, like a family history of heart disease, the Fetal Cardiology Program at Children's offers ultrasound by experienced cardiologists who will carefully examine your baby's heart.
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BLOOD PRESSURE AFTER EXERCISE

2011-09-08T13:13:00.000+05:30

Normally, blood pressure increases from resting level with exercise. Based on
criteria used for exercise treadmill tests, any decrease in blood pressure during
exercise might be a sign of heart disease. The same is true, to a lesser extent, if
there is a failure of the blood pressure to increase with exercise. Once exercise
has stopped, blood pressure should return to resting levels and may even drop to
slightly below pre-exercise levels for a while based on a number of factors, like
any medications one might be taking, overall fitness level, and the type and
duration of exercise.

The whole question of what your fall in blood pressure really means depends on its
timing. If it occurs during exercise or soon after stopping, talk to your doctor
about having some sort of stress test (an exercise treadmill test or a stress
echocardiogram), because, even though you feel well, this could be a warning sign
of early heart disease. It may not be, but the exercise testing will help sort this
out.If you have any risk factors for heart disease (smoking, high blood pressure,
diabetes, high blood cholesterol levels, or close relatives with heart disease before age 45),then a treadmill test might be an even better idea.

BLOOD LOSS RECOVERY

2011-09-08T13:04:00.001+05:30

On average a normal, healthy individual who donates or looses a unit of blood (about 450 ml or ¾ pint) will fully recuperate from the blood loss in four to six weeks.

The four to six-week period I indicated is the time necessary to replace ALL these factors, though our bodies actually replace some of the individual components faster than others.

For example, the fluid (mostly water) lost in a blood donation, is replaced in only a few hours, provided the person drinks a moderate amount of water or healthy, non-alcoholic liquids to replenish the loss.

The other components of the blood, such as platelets and red cells begin to replenish immediately but take a bit longer to complete; usually within a few days or weeks depending on how much blood is lost.

Generally speaking, after losing a unit of blood, the body replaces the fluid and white cells within 24 hours, and platelets and plasma proteins within 48-72 hours. The red blood cells are completely replaced in 4-6 weeks.

How fast the entire blood loss is replenished obviously depends on the amount of blood lost, the size of the individual (for every 12-15 pounds of body weight, a human being has about one pint of blood) and the health of the individual from whom the blood is removed.

ANGIOPLASTY Vs BYPASS

2010-11-11T11:57:00.000+05:30

A person who has been taking medication for angina but is still experiencing frequent or severe chest pain may need either angioplasty to widen the narrowed artery, or coronary artery bypass surgery to create a different blood vessel for supplying the heart with blood.

Over the long run, the two procedures are equally successful in getting rid of chest pain and in preventing a heart attack or death. Angioplasty is an easier procedure to go through, however.

Some of its advantages are:

* Recovery is much shorter and less painful, requiring a one- or two-day hospital stay, compared to a stay for a week or more for bypass surgery.

* Angioplasty can be performed under local anesthesia (where the patient is sedated but awake), as opposed to general anesthesia (where the patient is asleep), which is needed for bypass surgery.

* The chest does not need to be opened, an advantage that substantially reduces pain, recovery time, and scarring.

* There is no need to use a heart-lung machine; this type of machine makes bypass surgery easier to do but increases the possibility of stroke.

Who Does Angioplasty Benefit?

# Angina pain that cannot be controlled by medication

# Severe narrowing of one or more arteries that poses a significant threat to a large area of heart muscle

# Severe narrowing of the left anterior descending artery (which supplies blood to a large part of the heart), but only if the heart muscle has not been significantly weakened by previous damage.

CARDIAC ARREST

2010-11-05T11:21:00.000+05:30

What is cardiac arrest?

Cardiac arrest is the sudden, abrupt loss of heart function. The victim may or may not have diagnosed heart disease. It's also called sudden cardiac arrest or unexpected cardiac arrest. Sudden death (also called sudden cardiac death) occurs within minutes after symptoms appear.

What causes cardiac arrest?

The most common underlying reason for patients to die suddenly from cardiac arrest is coronary heart disease. Most cardiac arrests that lead to sudden death occur when the electrical impulses in the diseased heart become rapid (ventricular tachycardia) or chaotic (ventricular fibrillation) or both. This irregular heart rhythm (arrhythmia) causes the heart to suddenly stop beating. Some cardiac arrests are due to extreme slowing of the heart. This is called bradycardia.

Other factors besides heart disease and heart attack can cause cardiac arrest. They include respiratory arrest, electrocution, drowning, choking and trauma. Cardiac arrest can also occur without any known cause.

Can cardiac arrest be reversed?

Brain death and permanent death start to occur in just 4 to 6 minutes after someone experiences cardiac arrest. Cardiac arrest can be reversed if it's treated within a few minutes with an electric shock to the heart to restore a normal heartbeat. This process is called defibrillation. A victim's chances of survival are reduced by 7 to 10 percent with every minute that passes without CPR and defibrillation. Few attempts at resuscitation succeed after 10 minutes.

How many people survive cardiac arrest?

No statistics are available for the exact number of cardiac arrests that occur each year. It's estimated that more than 95 percent of cardiac arrest victims die before reaching the hospital. In cities where defibrillation is provided within 5 to 7 minutes, the survival rate from sudden cardiac arrest is as high as 30–45 percent.

What can be done to increase the survival rate?

Early CPR and rapid defibrillation combined with early advanced care can result in high long-term survival rates for witnessed cardiac arrest. For instance, in June 1999, automated external defibrillators (AEDs) were mounted 1 minute apart in plain view at Chicago's O'Hare and Midway airports. In the first 10 months, 14 cardiac arrests occurred, with 12 of the 14 victims in ventricular fibrillation. Nine of the 14 victims (64 percent) were revived with an AED and had no brain damage.

If bystander CPR was initiated more consistently, if AEDs were more widely available, and if every community could achieve a 20 percent cardiac arrest survival rate, an estimated 40,000 more lives could be saved each year. Death from sudden cardiac arrest is not inevitable. If more people react quickly by calling 9-1-1 and performing CPR, more lives can be saved.

Sudden Cardiac Arrest
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ARRHYTHMIAS OF HEART - PART 2

2010-11-04T13:42:00.000+05:30

Is an arrhythmia serious?

In most people, arrhythmias are minor and are not dangerous. A small number of people, however, have arrhythmias that are dangerous and require treatment. Arrhythmias are also more serious if you have other heart problems. In general, arrhythmias that start in the lower chambers of the heart (called the ventricles) are more serious than those that start in the upper chambers (called the atria). Your doctor will talk with you about the type of arrhythmia you have and whether you need treatment.

Your doctor will ask if you have any of the symptoms listed in the box above. Your doctor may also do some tests. One of these tests is an electrocardiogram, also called ECG or EKG. During this test, your doctor will have you lie down so your heart can be monitored.

How do I know if I have an arrhythmia?

Your doctor may also ask you to walk on a treadmill while he or she monitors your heart, or may want to monitor your heart while you do your daily activities. One way to do this is to wear a machine, called a Holter monitor, that continuously records your heart's rhythms for 24 hours. If your doctor wants to monitor your heart for more than 24 hours, he or she might recommend an event-recorder, a machine that records samples of your heart's rhythms and can be worn for a couple of days or longer. Other tests, called electrophysiologic studies, may also give your doctor information about your heart.

What are some of the types of arrhythmias?

* Atrial fibrillation: The heart beats too fast and irregularly. This type of arrhythmia requires treatment and can increase your risk of stroke.
* Paroxysmal atrial tachycardia: The heart has episodes when it beats fast, but regularly. This type of arrhythmia may be unpleasant but is usually not dangerous.
* Ectopic beats: The heart has an extra beat. Treatment usually is not needed unless you have several extra beats in a row and/or other problems with your heart (such as heart disease or congenital heart failure).
* Ventricular tachycardia and ventricular fibrillation: The heart beats too fast and may not pump enough blood. These types of arrhythmias are very dangerous and need immediate treatment.

What's the treatment?

Treatment depends on the type of arrhythmia you have. Some mild arrhythmias require no treatment. Other arrhythmias can be treated with medicines. If another health problem is causing the arrhythmia, treatment is aimed at taking care of that problem. In more serious cases, other treatments are available:

* An artificial pacemaker is an electronic device placed under the skin on the chest. It helps the heart maintain a regular beat, especially when the heart beats too slowly.
* Cardiac defibrillation (very brief electric shock) can be used to stop an abnormal rhythm and restore a normal one.
* Surgery can correct certain types of arrhythmias. For example, arrhythmias caused by coronary artery disease may be controlled by bypass surgery. When an arrhythmia is caused by a certain area of the heart, sometimes that part of the heart can be destroyed or removed.

ARRHYTHMIAS OF HEART - PART 1

2010-11-04T13:26:00.000+05:30

Heart rhythm disorders (arrhythmias) are problems that affect the electrical system, or "wiring," of the heart muscle. Heart arrhythmias are very common and millions of people will experience an abnormal heart rhythm some time during their lives. Most are not serious.

Many irregular heart rhythms are harmless and go away on their own. Often they are caused by factors not related to the heart. Some heart rhythm disorders, however, are serious and may put people at risk for sudden cardiac death.

An electrophysiologist is like a detective. Fainting is like a hit-and-run crime, because the person has not fainted in front of you.So you have to put certain pieces of information together to try and solve it, because there’s a very good possibility that fainting will happen again.

Click here: Heart's Electrical Conduction

What is an arrhythmia?

An arrhythmia is a change in the rhythm of your heartbeat. When the heart beats too fast, it's called tachycardia. When it beats too slow, it's called bradycardia. An arrhythmia can also mean that your heart beats irregularly (skips a beat or has an extra beat). At some time or another, most people have felt their heart race or skip a beat. These occasional changes can be brought on by strong emotions or exercise. They usually are not a cause for alarm. Arrhythmias that occur more often or cause symptoms may be more serious and need to be discussed with your doctor.

What are the symptoms of arrhythmia?

Call your doctor if you have any of these symptoms, especially if you have heart disease or have had a heart attack.

* Palpitations or rapid thumping in your chest
* Feeling tired or light-headed
* Passing out
* Shortness of breath
* Chest pain

The heart has 4 compartments, or chambers. The walls of the heart squeeze together (contract) to push blood through the chambers. The contractions are controlled by an electrical signal that begins in the heart's natural "pacemaker" (called the sinoatrial node). The rate of the contractions is influenced by nerve impulses and hormones in the blood. A problem in any of these can cause an arrhythmia.

Minor arrhythmias may be caused by excessive alcohol use, smoking, caffeine, stress or exercise. The most common cause of arrhythmias is heart disease, particularly coronary artery disease, abnormal heart valve function and heart failure. However, arrhythmias can occur for no known reason.

ECTOPIC HEART BEATS

2010-11-04T13:15:00.000+05:30

# Ectopic heartbeat is an irregularity of the heart rate and heart rhythm involving extra or skipped heartbeats. Ectopic heartbeats are really just extra beats that make the heart 'bump' irregularly from time to time

# Ectopic heartbeats are small variations in an otherwise normal heartbeat that causes an irregular pulse. They may occur without an obvious cause and are usually harmless.

# Sometimes they are associated with chemical (electrolyte) problems in the blood, which need treatment. They can also happen with ischemia caused by a decrease in blood supply to the heart.

The difficulty with ectopic beats is that they tend to be more frequent and more noticeable when you're stressed or worried.

It is possible to find yourself in a bit of a vicious cycle with the ectopic beats adding to your anxiety and causing more palpitations.

Any additional unpleasant stress, such as period problems, is likely to add to your symptoms for the same reason.

# Ectopic beats were found in normal people who did not even feel that they had them. Even though there are causes of ectopic beats and they are various and they include:

1. Drinking too much caffeinated beverages.
2. Drinking alcohol.
3. Smoking cigarettes.
4. Exhaustion.
5. Not getting enough sleep.
6. Abnormal electrolytes in the blood.
7. Having a hyperactive thyroid gland.

# The ectopic beats, if they are few and far between, may be ignored. If you are anxious and ECG does not show anything, testing with Holter Monitor will find the answer.

# In adults, ectopic beats are common. Their causes should be investigated even if it turns out that no treatment is needed.

HEART ENLARGEMENT

2010-11-01T16:31:00.000+05:30

Heart enlargement can be pathological (related to significant heart disease) or physiological (related to exercise or other physical activity). Any sustained condition or activity that makes the heart work harder can enlarge it, including:

* Hypertension is the medical term for high blood pressure (the force of blood against artery walls).Heart failure

* Coronary artery disease
* Valve disease
* High blood pressure (hypertension)
* Obesity
* Coronary artery spasm
* Cardiac ischemia
* Thyroid disease
* Severe anemia
* Excess iron or protein build-up in the body
* Excessive alcohol use
* Obstructive sleep apnea
# A different sort of enlarged heart is known as hypertrophic cardiomyopathy. This form of cardiomyopathy occurs when the heart’s muscles thicken abnormally. This thickening usually happens in the left ventricle since it is the main pumping muscle.

# Additionally, a small number of patients have an enlarged heart with no known cause (idiopathic).

# Another condition, sometimes referred to as “athlete’s heart,” can occur in high-level athletes who engage in regular, sustained and often intense exercise. In most cases, this is not a medically significant or dangerous condition for them.

Treatment and prevention

Treatment for an enlarged heart may include medications, such as ACE inhibitors, to lighten the heart’s pumping load and keep it from further enlargement. Treatment should also be directed at the cause of the enlarged heart (e.g., high blood pressure, valvular heart disease). Medications such as diuretics may be prescribed for those with heart failure.

Prevention of the underlying diseases that could cause the heart to enlarge, and early diagnosis once it has developed, is crucial. This includes:

* Eating a balanced, low-fat diet
* Maintaining healthy cholesterol levels
* Keeping blood pressure under control
* Engaging in a regular exercise program
* Visiting the physician regularly

Proper management, such as controlling high blood pressure, treating valve disease and discontinuing alcohol consumption may reverse an enlarged heart.

HEART MUSCLE

2010-11-01T16:24:00.000+05:30

A type of muscle found only in the walls of the heart; it is under control of the autonomic nervous system.

Cardiac muscle is like skeletal muscle in that it is striated and multinucleate, and like smooth muscle in that the nuclei are centrally located and many cells are required to span the length of the muscle. It differs from both skeletal muscle and smooth muscle in that its cells branch and are joined to one another via intercalated disks. Intercalated disks allow communication between the cells such that there is a sequential contraction of the cells from the bottom of the ventricle to the top. This makes possible the maximal ejection of blood from the ventricle during contraction and occurs without nervous innervation to each cell or group of cells.

Cardiac muscle also differs from the other two muscle types in that contraction can occur even without an initial nervous input. The cells that produce the stimulation for contraction without nervous input are called the pacemaker cells.

How cardiac muscle contracts?

Action potentials initiate the contraction of our hearts. The contraction of cardiac muscle is triggered in a different fashion then contraction of the skeletal muscle, which is caused by the electrical impulses from motor nerve terminals located at individual muscle fibers. These motor nerve terminals are networked and coordinated by the central nervous system.

Contrary to the skeletal muscle cells, the heart cells have no motor nerve terminals attached to them. If each of the millions of cardiac muscle cells were to have a separate nerve, the heart would be a huge organ. The cells of the heart remedy this lack of motor nerve terminals by using their own type of stimulus. They communicate with each other directly by passing electrical impulse to their neighbors through special channels called gap-junctions. This enables the heart to be stimulated at only one location, with the electrical impulse passing on to the rest of the heart muscle, causing it to contract.

What exactly happens to the muscle cells when they are stimulated?

Inside each cardiomyocyte are hundreds of myofibrils which are thin, elongated structures. Each myofibril, in turn, consists of thin filaments and thick filaments. Each of the thin filaments is composed of a protein called actin. Each of the thick filaments is composed of a protein called myosin. Each myosin filament is composed of about 200 myosin molecules. Each myosin molecule contains what is called a myosin head. Inside each cardiomyocyte there are compartments filled with calcium. The action potential causes these compartments to release the calcium into the cell. This calcium allows myosin heads to bind to actin filaments and pull them by a process called a power stroke. That is how action potential causes the individual muscle cells to contract.

HEART MURMURS

2010-11-01T15:23:00.000+05:30

What Is a Heart Murmur?

A heart murmur is a whooshing sound between the beats that a doctor hears through a stethoscope. The whoosh is just an extra noise that the blood makes as it flows through the heart.

Murmurs have grades. Grade 1 is the softest-sounding murmur, and Grade 6 is the loudest. A murmur graded 4, 5, or 6 is so loud you can actually feel a rumbling from it under the skin if you put your hand on the person's chest.

Most heart murmurs don't mean anything is wrong. Doctors may call these "innocent," "functional," or "normal" murmurs. They are caused by blood rushing through the valves in a normal heart and are nothing to worry about.

Even though most murmurs do not mean anything is wrong, sometimes a heart problem can cause a murmur. The heart may have a hole in it, a heart valve may leak, or a valve may not open all the way.