Cardiac Output

Symptoms You Should Know About Cardiac Arrhythmias

Pacemakers have been around for decades, yet there is still a lot of misunderstanding about how they work, what they do, and who needs them. Millions of people around the world wear pacemakers, yet it is something that is rarely talked about.

People get pacemakers to correct a problem with the heart known as a cardiac arrhythmia. In layman's terms, it means the heart's natural rhythm is getting out-of-whack.

While just about everyone probably experiences occasional but very short bouts of out-of-rhythm cardiac activity, some people have stubborn arrhythmias that cause symptoms, impair their ability to lead a normal life, and are largely unpredictable. These people need pacemakers. Symptoms that may mean you need a pacemaker include fatigue, dizziness, lightheadedness, even fainting, as well as inability to exercise without getting overly out of breath.

These are pretty vague symptoms and a person could easily have all of those conditions and not need a pacemaker. But let's talk about what's really going on.

The healthy heart beats in a specific rhythm that coordinates the heart's upper chambers (atria) and lower chambers (ventricles) in such a way that the heart beat is quite efficient at moving a very large quantity of blood throughout the body. This blood is called cardiac output. If cardiac output drops to zero, the person dies in a matter of minutes.

But in many cases, the electrical system of the heart (not the pumping ability) starts to falter. This is an electrical problem of the heartnot the heart's inability to pump out blood efficiently. Yet many people do not even realize the heart as an electrical system.

Electrical impulses produced by the heart guide the heart's rhythm. If the heart stops producing electricity in a regular manner or the electricity no longer travels properly through the heart muscle, the result can be an arrhythmia.

There are two main types of arrhythmia that can lead to a person's getting a pacemaker. The first is called "sinus node dysfunction," which sounds very complicated. It really means that the heart no longer produces electrical energy at the right rate.

The heart has the amazing ability to produce electricity. This is accomplished by a small area of tissue called the sinoatrial node (nicknamed "sinus node" or just "sinus") in the upper right hand side of the heart. If the sinus node gets sluggish or produces electricity erratically or produces electricity fine at low rates but can't keep up when you exercise and need a faster heart rate ... that is sinus node dysfunction.

About half of all people with pacemakers have this condition. The resulting arrhythmia for a person with sinus node dysfunction is a heart rate that is too slow to support normal activity. The medical term for this is "sinus bradycardia." Because you don't get enough cardiac output to do normal things, you can find yourself getting winded, tired, dizzy, or even passing out doing things you used to do.

The second kind of arrhythmia that can lead to a pacemaker sounds a lot simpler, but the name is a bit of a misnomer. It's called "heart block." Heart block isn't really a blockage at all. Instead, it means that the electrical impulses produced by the heart no longer travel efficiently through the heart muscle. The electrical energy gets delayed or even blocked in some areas.

In the healthy heart, the electrical energy that causes the heart to beat starts in the sinoatrial node (top, right side of the heart). It then travels out over the atria and then downward. As it makes its ways to the ventricles, it passes through a junction called the "atrioventricular node" or AV node.

Once the electrical energy goes through the AV node, it travels to the ventricle and causes the ventricles to contract and pump blood. Heart block occurs when there is a problem at the AV node. Sometimes the electrical energy gets delayed in such a way that the atria and ventricles are no longer working together.

In extreme forms of heart block, the energy from the top half of the heart cannot make its way down to the bottom half at all (this is called "complete heart block"). Because the atria and ventricles do not work in harmony, cardiac output is impaired. This can result in the very same list of symptoms: lightheadedness, dizziness, shortness of breath, feeling tired all of the time, and even fainting.

About half of all people who need pacemakers have some form of heart block (it can be mild to severe).

Arrhythmias can get fairly complicated. For example, one person might have both types of these arrhythmias that require a pacemaker, that is, one person can have sinus node dysfunction and heart block at the same time. Even individuals who might only have one arrhythmia right now can develop another kind of arrhythmia in the future.

Pacemakers accomplish this by "filling in the missing beats."

Pacemakers are small electrical devices implanted in the chest. They deliver electrical energy to the heart at precisely the right moment to keep it beating in a way that is as "normal" as possible. In many patients, pacemakers restore normal heart rhythm. In some patients, the arrhythmia may be too severe for a normal heart rhythm to be restored, but the pacemaker can at least come close.

Pacemakers "know" when to deliver electrical energy to the heart because they monitor every beat of the heart and respond according to how the physician programs them. This is a useful feature since many pacemaker patients do not require constant pacing. In fact, for many people, arrhythmias are not permanent at all, but come and go, sometimes for brief periods. The pacemaker monitors the heart's activity and jumps in with stimulating (pacing) energy when an arrhythmia occurs.

There is, at the moment, no cure for arrhythmias in the sense that an erratic heart rhythm cannot be restored with an operation or a pill. True, operations, pills, and other remedies can help manage symptoms or even correct part of the problem.

Pacemakers are actually very safe ways of dealing with specific arrhythmias. Although they're implanted in the body, they do not deliver drugs or other chemicals into the body. They use electricity, which is the very substance the body would generate itself, if it could.

Doctors have a lot of flexibility in terms of how the pacemaker is programmed, so they are suitable for a wide range of people, from athletes to newborns to bedridden seniors.

And pacemakers have a memory so that they can report back to the doctor what's been going on in the patient's heart. Not all arrhythmias can be treated with a pacemaker. But for rhythm disorders like heart block or sinus bradycardias, pacemakers are a safe, effective, and well proven technology that can make a big difference in the lives of those that need them.

About the Author

Need to know more about pacemakers? Get the information you need from http://www.pacemaker411.com . Pacemakers have helped a lot of people, but there aren't many places you can get the straight, everyday-language story of how they work.

Top 40 Songs For Exercise

Many people who workout on a regular basis have discovered that they have certain choice music that helps them to perform their exercise regimen. Music can be good for relaxation, but by choosing songs with the proper tempo and beat characteristics, it also makes your heart beat faster and makes your body more willing to undergo the physical stress of exercise. In many respects, exercise is similar to dance. No one wants to dance without music, do they? The same principle applies when you work out. You can locate the work out music of your choice on internet radio.

 

If you are a music lover, music is connected to every aspect of your life. You may have favorite music that you associate with many of life's tasks, such as cooking,driving, and numerous others. If you love exercising and working out, then it just follows that you have a song or two for that as well.

 

Three great, "Top 40" songs for your workouts are "Come Fly Away" by Benny Benassi and Channing, "Turnin Me On" by Keri Hilson and Lil Wayne, and "Homecoming" by Hey Monday. These are all fairly new releases with a common thread, and upbeat tempo that invigorates the listener. Which is main reason that a lot of people who workout are selecting this music to accompany them during their exercise routine. These music helps to energize them and give them the extra boost they need. In addition, this music has some other health benefits.

 

The biggest advantage of mixing music with your workout is that up tempo music helps to stimulate cardiovascular activity. If the music stimulates your, it will help you through the workout and increase your cardiac output. It will improve your blood circulation, make your routine more effective, and help you burn more calories. You can get access to the music for free on internet radio.

 

For excellent results the tempo of the music should be in the range of 110 to 130 beats per minute. Your workout playlist should also be designed to accommodate a full workout, starting slowly and allowing your body to adjust and adapt to the activity before increasing in intensity. After the initial warm up time, the beat of the music should become more tempo to encourage more vigorous exercise. After the workout is complete, the music should slow down again for a cool-down period to allow the body to relax.

 

Music has numerous purposes in our daily lives. We often listen to music to relax. If a person wants to be energized and to be encouraged to keep on moving, music can be used as a cardiovascular stimulant. It helps when the gym that you are a member of always has good music playing in the background. If the background music does not appeal to you then, by all means use your iPod. Your mood will be set by the music. The addition of music to and otherwise mundane exercise regiment will make it a more enjoyable experience. It might even become fun.

Explain why the cardiac output of an athlete increases before an important race?

r u refering to adrenaline?

[Original Article] Cardiovascular-Emotional Dampening: The Relationship Between Blood Pressure and Recognition of Emotion (psychosomaticmedicine)

Objective

Persons with elevated blood pressure (BP) show dampened emotional responses to
affect-laden stimuli. We sought to further examine cardiovascular-emotional
dampening by examination of the relationship between resting hemodynamic
measures and recognition of emotion in an African American community-based
sample.

Methods

Participants were 106 African American men and women (55 women; mean age =
52.8 years), mainly low in socioeconomic status, and part of the Healthy Aging
in Nationally Diverse Longitudinal Samples pilot study. Participants evaluated
emotional expressions in faces and sentences using the Perception of Affect
Test (PAT). Resting BP, total peripheral resistance (TPR), cardiac output, and
heart rate were obtained continuously using a Portapres BP monitor.

Results

Total PAT scores were inversely related to systolic (_r_ = -0.30) and
diastolic (_r_ = -0.24) BPs, TPR (_r_ = -0.36), and age (_r_ = -0.31; _p_
values < .01) and were positively related to cardiac output (_r_ = 0.27) and
education (_r_ = 0.38; _p_ values < .01), as well as with mental state (_r_ =
0.25) and body mass index (_r_ = -0.20; _p_ values < .05). Accuracy of emotion
recognition on the PAT tasks remained inversely related to TPR and BP after
adjustment for demographic variables, medication, mental ...

psychosomaticmedicine

The Physiology of Cardiac Output