The electrocardiogram is a test performed to make sure all electrical activity of the heart is normal and working properly. “By positioning leads (electrical sensing devices) on the body in standardized locations, information about many heart conditions can be learned by looking for characteristic patterns on the EKG.” KULICK, MD, FACC, FSCAI (2016) The activity is shown as spikes and dips called waves on the tracing paper, that comes out of the ECG machine. These waves create different waveforms to be analyzed for diagnoses. A waveform is movement recorded that is away from the baseline, either positive or negative.
The P- QRS- T sequence is the measurement of one heartbeat. “One cardiac cycle is equivalent to one complete heartbeat.” Jones. (06/2014) p. 8. When broken down there are three separate sequences the P-wave, QRS, and the T-wave. These three sequences represent depolarization, depolarization and then repolarization which produces contractions in the heart. The QRS complex is represented by the second depolarization activity picked up by leads. This wave form is created by the depolarization of the ventricles. The QRS complex can be represented by any one, two, or three combinations of the three waves and still recognized as the QRS waveform.
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The shape of the QRS complex consists of the Q wave, which is the negative deflection before the R wave, then the R wave, that is the first positive deflection after the Q wave, and the S wave, which is the first negative deflection after the R wave. “The normal duration of a QRS complex is about 0.10 second when the speed and direction of depolarization are normal and the voltage (amplitude) generated during ventricular depolarization are normal.” Jones (06/2014) p. 137. Amplitude of the QRS complex varies but the normal range is 5mm to 15mm
1.2 & 1.3 Explain The Cardiac Cycle And Describe How The Heart Rate Is Modified According To The Needs Of The Body
Which of the following is NOT part of ECG Changes that is associated with MI?
When evaluating systolic and diastolic function it is extremely important to obtain images of wall motion, wall thickness, chamber size and ventricular end diastolic pressure.
Abnormalities that are being examined includes some arrhythmias, such as premature ventricular contraction or atrial fibrillation.
Other than atrial fibrillation and atrial flutter, this is the most common supraventricular tachycardia seen in practice.11 A large minority of adults (up to 40% in some cohorts) are born with 2 pathways that can conduct electricity in the AV node, rather than 1. Under the right conditions, AV node reentrant tachycardia (AVNRT) can be initiated by a premature atrial or ventricular beat. If the 2 pathways are able to sustain a stable circuit, the atrium and the ventricle are depolarized almost simultaneously. As a result, on the ECG, the P wave is not seen, is buried in the QRS complex, or is seen at the terminal portion of the QRS, typically as a pseudo-s (negative) wave in the inferior leads or a pseudo-r0 in lead V1. Because this tachyarrhythmia depends on the AV node, both vagal maneuvers and adenosine are potential acute treatment options. In the outpatient setting, if the patient is in a sustained supraventricular tachycardia, attempting vagal maneuvers
The study of cardio physiology was broken up into five distinct parts all centering on the cardiovascular system. The first lab was utilization of the electrocardiogram (ECG). This studied the electrical activities of the heart by placing electrodes on different parts of the skin. This results in a graph on calibrated paper of these activities. These graphs are useful in the diagnosis of heart disease and heart abnormalities. Alongside natural heart abnormalities are those induced by chemical substances. The electrocardiogram is useful in showing how these chemicals adjust the electrical impulses that it induces.
The ventricular ectopic pacemaker produced the rhythms as 30-40 beats/minutes much slower than the generally produced by SA node which is 60-100
blood from the ventricle chambers during systole. Reduction in the contraction is caused by the increase
When the heart contracts a shockwave is produced pumps blood forcefully out of the ventricles into the aorta the shock wave travels along the fibres of the arteries and is commonly called the arterial or peripheral pulse. The pulse weather regular, irregular, thready or strong, gives a good overall picture of the clients health status. Several characteristics should be assessed when measuring the radial pulse rate, rhythm, amplitude, contour and elasticity of the various characteristics. amplitude can be quantified as follows 1 thready or weak 2 normal 3bounding If abnormalities are noted during assessment of the radial pulse further assessment should be performed for more information on assessing pulses and abnormal pulse findings
Due to the fact that we thrive in a prevalent world of technological advances significantly more convenient machines have been granted. Furthermore, the diagnostic tests that can be done to evaluate heart function are:
Patient Overview: Mrs M is a 78 year old female who lives at home with her husband. She has never smoked and has reduced her alcohol consumption due to her health conditions. Mrs M eats a well-balanced diet with small meals throughout the day and exercises by walking 3 times a week for 30 minutes. She manages her own medications and uses weekly pill boxes and timers creating a strict routine to remind her when to take her medications. Mrs M doesn’t have any difficulties with her medications such as being able to read and understand labels or problems opening boxes.
The heart has a relatively long refractory period due to the plateau phase. The plateau phase occurs from the maintenance of a high calcium conductance and a delay in the subsequent increase in potassium conductance after a cardiac action potential. The heart membrane remains in a refractory or contracted state until the heart has fully returned to a relaxed state; therefore, tetanus or wave summation does not occur in cardiac muscles (Randall, 2002). When the frog’s heart was stimulated with single stimuli, an extrasystole and an increase in frequency was observed during the relaxation phase, but the amplitude remained constant. These results were analogous to the multiple stimuli treatment, which we expected. Because both single and multiple
AIM: - the aim of this experiment is to find out what the effects of exercise are on the heart rate. And to record these results in various formats. VARIABLES: - * Type of exercise * Duration of exercise * Intensity of exercise * Stage of respiration
The ECG has had a huge impact on society in many ways. Among the most beneficial is that the data collected can be extrapolated to predict heart disease in an individual and thus lead the individual to alter their lifestyle, whether by taking medication or changing diet and exercise routine (3). This is increasingly relevant with the rising number of healthy, young athletes dying from sudden cardiac arrest after showing no previous symptoms (5). With the data collected by the electrocardiogram, this can be predicted and thus save lives. One harmful effect of the ECG is that the data is not always reliable; sometimes the data will find false-positive evidence of heart disease or a heart attack when there is none, and in other cases, the device isn’t consistently able to predict heart disease in people without a high risk of having heart problems (1). Overall, however the ECG is a device that ultimately will benefit people and reduce the number of lives taken by heart
Decreased cardiac output r/t altered heart rate as evidenced by ECG results, irregular HR, and HR of 165 beats per minute.