What are the phases of ECG?
A typical ECG tracing of the cardiac cycle (heartbeat) consists of a P wave (atrial depolarization ), a QRS complex (ventricular depolarization), and a T wave (ventricular repolarization). An additional wave, the U wave ( Purkinje repolarization), is often visible, but not always.
What does it mean when EKG says sinus rhythm?
Sinus rhythm is the name given to the normal rhythm of the heart where electrical stimuli are initiated in the SA node, and are then conducted through the AV node and bundle of His, bundle branches and Purkinje fibres. Depolarisation and repolarisation of the atria and ventricles show up as 3 distinct waves on ECG.
What happens in each phase P QRS T?
The sinoatrial node (SA) is the pacemaker of the heart and produces the P wave. The QRS wave is produced by the atrioventricular node (AV). The P wave in an ECG complex indicates atrial depolarization. The QRS is responsible for ventricular depolarization and the T wave is ventricular repolarization.
What is the difference between sinus rhythm and arrhythmia?
Definition and types The sinus node is known as the heart’s natural “pacemaker,” meaning it is responsible for the rhythm of a person’s heartbeats. Normal sinus rhythm is a regular rhythm found in healthy people. Sinus arrhythmia means there is an irregularity in the heart rhythm, originating at the sinus node.
What is considered normal sinus rhythm?
When everything is working smoothly, you have a normal sinus rhythm and your heart beats between 60 and 100 times per minute.
What happens during T wave?
The T wave on the ECG (T-ECG) represents repolarization of the ventricular myocardium. Its morphology and duration are commonly used to diagnose pathology and assess risk of life-threatening ventricular arrhythmias.
How do you read sinus rhythm?
If there is sinus rhythm, and the heart rate is less than 60 beats per minute, then sinus bradycardia is present. If there is sinus rhythm, and the heart rate is greater than 100 bpm, then sinus tachycardia is present. The links below take you to examples of each of these.
What is Phase 1 of the cardiac cycle?
A-V Valves Open; Semilunar Valves Closed This is the first phase of the cardiac cycle. It is initiated by the P wave of the electrocardiogram (ECG), which represents electrical depolarization of the atria. Atrial depolarization initiates contraction of the atrial musculature.
What are the 4 phases of the cardiac cycle?
Phases of the Cardiac Cycle
- Atrial Systole and Diastole. Contraction of the atria follows depolarization, represented by the P wave of the ECG.
- Ventricular Systole.
- Ventricular Diastole.
- Glossary.
Is the relaxation phase?
Systole is the contraction phase of the cardiac cycle, and diastole is the relaxation phase.
What should a sinus rhythm look like?
When a person has a normal sinus rhythm on their EKG, these beats are in a regular, orderly rhythm. Each should look like the previous and will be as evenly spaced with each other. An EKG of a person with A-fib is very different in its appearance when compared with sinus rhythm.
What are the types of sinus rhythm?
Sinus tachycardia, which is a faster heart rate, beating greater than 100 beats per minute. Sinus bradycardia, which is when the heart rate beats slower or less than 60 beats per minute.
What happens during the P wave?
The first wave (p wave) represents atrial depolarisation. When the valves between the atria and ventricles open, 70% of the blood in the atria falls through with the aid of gravity, but mainly due to suction caused by the ventricles as they expand.