Questions tagged [cardiac-physiology]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0 votes
0 answers
39 views

Should we invert other ECG leads if aVR was positive?

I would like to seek your kind guidance in understanding the right way of solving this question. (for the context, so far we only covered normal ECG and axis deviation) The question displays all 12 ...
helplessstudent147's user avatar
1 vote
1 answer
86 views

How to determine QRS voltage from ECG?

Attached below is a question from my textbook "Guyton and Hall Textbook of Medical Physiology Review, 4e" and I am confused because the solutions manual has the answer as B (0.5mV), implying ...
helplessstudent147's user avatar
1 vote
0 answers
14 views

On an ECG, do we take the J point to be the baseline or the TP segment?

I'm studying current of injuries and the diastolic current theory is explained as such: The ECG machine is programmed to keep the T-P segment at baseline with everything else on the strip moved up or ...
Filthyscrub's user avatar
2 votes
2 answers
124 views

Confusion regarding splitting of the s2 heart sound

I recently read that during inspiration the negative pressure in the thoracic cavity leads to increased venous return to the right atrium. This leads to late closure of the pulmonary valve as the ...
Aaisha Aussie's user avatar
1 vote
1 answer
174 views

Why do ventricular action potentials have no local potentials like neuronal action potentials?

I noticed that the depolarization in the ventricular action potential (bottom image) is just a sharp spike, with no local potential that gradually achieves the threshold potential (like the top image, ...
Doe Pull's user avatar
1 vote
1 answer
17 views

How can myocyte contract in "isovolumetric contraction" phase of cardiac cycle without shortening?

What is the difference between a contraction that shortens the muscle and generates force and the isovolumetric contraction that generates force with shortening the muscle??
Mohammed Showekh's user avatar
1 vote
1 answer
41 views

What is considered moderate when referring to (sub)acute hypertension, hyperthermia and tachycardia?

I'm reading about the toxicology of LSD, and the acute and subacute adverse effects (hypertension, hyperthermia, tachycardia) have been described as moderate in this article, modest in this article (...
A. Kvåle's user avatar
  • 135
5 votes
1 answer
91 views

Bradyarrhythmia & Bradycardia- same or different?

Do Bradyarrhythmia & Bradycardia denote same abnormality or are there some finer differences between the two?? In text provided by my college, it appears bradycardia condition comes under the ...
Pearl Dua's user avatar
0 votes
1 answer
935 views

Why squatting leads to decrease in MVP murmur

Mvp = mitral valve prolapse Hcm = hypertrophic cardiomyopathy Now, I understand that during squatting preload and afterload will increase and both of them would lead to increased LV volume, but how ...
Physicsapproval's user avatar
1 vote
0 answers
13 views

Why do changes in Effective Refractory Period in Response to Antiarrhytmics occur and how do they help in treating the arrhythmia?

I am having trouble understanding two related concepts. First, why changes in ERP occur when there is the administration of certain antiarrhythmics (eg: Class IC). A neat explanation that I have ...
abacus143's user avatar
  • 453
1 vote
1 answer
34 views

What is the functional difference between cardio-pulmonary and the baroreceptors in the regulation of Blood pressure?

Guyton mentions two types of receptor- the baroreceptors and the cardiopulmonary receptors- that are involved in the maintenance of the acute changes in blood pressure. I just wanted to know how these ...
abacus143's user avatar
  • 453