What is r - wave amplitude, Biology

Assignment Help:

Q. What is R - Wave Amplitude?

The R-wave amplitude in the lateral precordial leads usually decreases more in normal than in abnormal subjects and correlates with left ventricular function. Patients with CAD (severe) are likely to have an increase in the R-wave amplitude with exercise. As exercise progresses and the heart rate increases, R-wave amplitude increases normally until the heart rate is approximately 120 or 130 beats per minute, and then the amplitude begins to decrease. This suggests that for the R-wave to have significance, an increase in amplitude should be at a heart rate greater than 120 bpm. The sensitivity of an R-wave increase is rather poor but the specificity can be good if the patient reaches high heart rates. Stress test responses are difficult to analyze in patients with LBBB. Lee and colleagues reported that R-wave changes in 23 patients with LBBB had a 93 per cent sensitivity, 88 per cent specificity and 93 per cent predictability. A reduction in amplitude helps to predict normal coronary arteries and good left ventricular function in LBBB. Berman and associates used the sum of the R-waves in aVL, aVF and V3 and V4, plus S and V1 and V2 and were able to identify CAD in 93 per cent of 230 patients subsequently studied with coronary angiography. An R-wave increase is reported with vasospastic angina and early in the course of a myocardial infarction, where it is predictive of the severity and the likelihood of severe arrhythmias.


Related Discussions:- What is r - wave amplitude

Define the dietary recommendations for epilepsy, Define the Dietary Recomme...

Define the Dietary Recommendations for epilepsy? A 3: 1 ketogenic diet is recommended. The time taken for reversing the usual ratio of 1:3 to 3: 1 is about 4 days. How will we

Aortic allograft -biological valves, Aortic Allograft (Homograft) :  ...

Aortic Allograft (Homograft) :  In the earlier years fresh antibiotic preserved aortic allografts were tried. As the shelf life is limited, availability of all sizes at all t

Which molecule should be most radioactive, Yeast is cultured in the presenc...

Yeast is cultured in the presence of radioactive phosphate and the following biological molecules are purified. Which molecule should be most radioactive? A. An oligosaccharide B.

Which functional group cross-linked in protein, Which functional group (sid...

Which functional group (side-chain) can be "cross-linked" in protein? a. sulfhydryl b. amino c. Phosphate d. Hydroxyl e. Carboxyl

Descriibe mechanical ventilation and cardiac performance, Descriibe Mechani...

Descriibe Mechanical Ventilation and Cardiac Performance During spontaneous breathing, the intrathoracic and intrapulmonary pressures are negative, while with mechanical venti

What is the aim of specialised assessment, What is the aim of specialised a...

What is the aim of specialised assessment The aim of specialised assessment is often to identify a syndrome and specify its probable basis in abnormal brain function. The basi

Role of glucocorticoids in controlling gene expression, Define Role of Gluc...

Define Role of Glucocorticoids in controlling gene expression? Glucocorticoids are another class of hormones involved in the regulation of lipogenic enzymes, but their role in

What is fermentation, What is Fermentation ? Fermentation is a process ...

What is Fermentation ? Fermentation is a process used by anaerobic organisms and certain cells of aerobic organisms, such as muscle cells deprived of oxygen, to obtain addition

Classification of environmental disasters, The Environmental Disasters Are ...

The Environmental Disasters Are Classified Into Two Major Categories: 1.      Natural Disasters like Earthquakes, Tsunami, Landslides, Cyclones, Floods, and Droughts Etc. 2.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd