How To Read an EKG?

Posted: April 1st, 2011 | Filed under: Heart Health Education Resources | Tags: ECG, ECG recorders, Portable ECG Machine, Portable EKG Machine |

The P Wave P waves are caused by atrial depolarization. In normal sinus rhythm, the SA node acts as the pacemaker. The electrical impulse from the SA node spreads over the right and left atria to cause atrial depolarization. The P wave contour is usually smooth, entirely positive and of uniform size. The P wave duration is normally less than 0.12 sec and the amplitude is normally less than 0.25 mV. A negative P-wave can indicate depolarization arising from the AV node.

Note that the P wave corresponds to electrical impulses not mechanical atria contraction. Atrial contraction begins at about the middle of the P wave and continues during the PR segment. The PR Segment PR segment is the portion on the ECG wave from the end of the P wave to the beginning of the QRS complex, lasting about 0.1 seconds. The PR segment corresponds to the time between the end of atrial depolarization to the onset of ventricular depolarization. The PR segment is an isoelectric segment, that is, no wave or deflection is recorded. During the PR segment, the impulse travels from the AV node through the conducting tissue (bundle branches, and Purkinje fibers) towards the ventricles. Most of the delay in the PR segment occurs in the AV node. Although the PR segment is isoelectric, the atrial are actually contracting, filling the ventricles before ventricular systole.

The QRS Complex In normal sinus rhythm, each P wave is followed by a QRS complex. The QRS complex represents the time it takes for depolarization of the ventricles. The Q wave is not always present. The R wave is the point when half of the ventricular myocardium has been depolarized. The normal QRS duration range is from 0.04 sec to 0.12 sec measured from the initial deflection of the QRS from the isoelectric line to the end of the QRS complex.

Normal ventricular depolarization requires normal function of the right and left bundle branches. A block in either the right or left bundle branch delays depolarization of the ventricles, resulting in a prolonged QRS duration.

The ST Segment The ST segment represents the period from the end of ventricular depolarization to the beginning of ventricular repolarization. The ST segment lies between the end of the QRS complex and the initial deflection of the T-wave and is normally isoelectric. Although the ST segment is isoelectric, the ventricules are actually contracting.

The T Wave The T wave corresponds to the rapid ventricular repolarization. The wave is normally rounded and positive.

Recipes for Heart Attack!!

Posted: April 27th, 2010 | Filed under: Heart Disease Prevention | Tags: Heart Disease, Heart Health, Heart Staple, HeartStaple, Intelligent Health, Portable ECG Machine, Portable EKG Machine, Risk Factor, Risk Factors for Heart Disease |

Happy Earth Day Today with Top Ten Actions!

Posted: April 22nd, 2010 | Filed under: Charity 2.0 | Tags: Earth Day, Happy EArth Day, Portable ECG Machine, Portable EKG Machine, Portable HEart Rate Monitor |

Top 10 actions

Earth Day Canada president Jed Goldberg has identified his top 10 actions to make every day Earth Day.

1. Think before you act. Shopping has become a form of entertainment. While it can be difficult to avoid the seduction of advertising, Goldberg advises to think about what you need, not what you want, before you buy.

2. It’s all about conservation. Goldberg says we need to make the shift from being “consumers” to “prosumers” – producing consumers – to conserve energy and resources. Planting a garden is a great way to start.

3. Go vegetarian one day a week. Meat production has a huge environmental impact. Eating lower on the food chain just one day a week helps to conserve water, reduce greenhouse gas emissions and preserve valuable farmland.

4. Rethink convenience. Goldberg says people do things because they perceive that it’s easier, but easy isn’t always what’s best. Doing things in an environmentally responsible way can ultimately end up being more convenient and much cheaper, too! One example, stop buying bottled water and use tap water instead.

5. Eat and shop locally. Most of our food travels thousands of kilometres to get to our dinner plates. Ditto for our clothing and other consumers goods. Supporting local businesses also helps to build strong local communities.

6. Vote with your dollar. Advertisers and producers are conscious of what consumers want says Goldberg. Take the time to express your opinion to store owners with your wallet and your voice.

7. Use active transportation. Whether it’s walking, cycling or rollerblading, when you use your body to get from A to B instead of a motorized vehicle, you not only get the benefit of improved fitness while reducing your environmental impact, but you get to experience your community.

8. Borrow, don’t buy. Consider renting, borrowing or sharing what you need.

9. Refashion your yard. Instead of trying to achieve the perfect, lawn, why not get rid of the lawn altogether. Plant native shrubs, wildflowers or a vegetable garden. You’ll use fewer resources and free yourself from the lawnmower, too!

10. Use your sphere of influence. Collectively we have a great influence over our politicians, says Goldberg. Engage your family, friends, coworkers and community.

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