The heart is a muscular pump made up of four chambers . The two upper chambers are called atria. The two lower chambers are called ventricles. The first upward pulse of the EKG signal, the P wave, is formed when the atria contracts to pump blood into the ventricles. In Atrial Fibrilation there will be many “fibrillation” beats instead of one P wave. The next large upward spike segment, the QRS Complex, is formed when the ventricles are contracting to pump out blood. Main Features to Consider are its width (too narrow means Supraventricular tachycardia (SVT) arising from improper electrical activity of the heart., too broad - could mean hyperkalaemia or sodium-channel blockade), height (voltage) and specific shape. The ST segment, measures the end of the contraction of the ventricles to the beginning of the rest period before the ventricles begin to contract for the next beat..The T wave, measures the resting.
The accuracy of the ECG depends on the condition being tested. A heart problem may not always show up on the ECG. Many medicines can change the results of this test.
An EKG is done to:
- Check the heart's electrical activity and examine other possible abnormalities - e.g. in the walls of the heart chambers
- Find the cause of unexplained chest pain or pressure.
- Find the cause of shortness of breath, dizziness, fainting, and palpitations (rapid or irregular heartbeats), high blood pressure, and other conditions
AfibAlert heart monitor specifically designed for Atrial Fibrillation
ECG check that attaches to the back of a smartphone,
The HeartCheck Handheld™ EKG device that can be used in arrhythmia screening/monitoring and stroke
Kardia - a clinically-proven personal EKG solution that captures medical-grade single-lead EKGs via a high-end tablet, smartphone or Apple Watch.
Choicemmed offers several products ranging from personal (MD100E) handheld monitors to ambulatory Holter ECG recorders. ReadMyHeart, Dimitek DiCare-m1CC, and PC-80B color are examples of other stand-alone handheld monitors that don't require mobile phones to operate.
Many more diagnostic hand-held devices or wearables are in development including a disposable HealthPatch® MD that claims to detect Single-Lead ECG, Heart Rate, RR Interval, Heart Rate Variability, Respiratory Rate, Skin Temperature, Body Posture, Fall Detection and activity including steps.