Describe fourth heart sound in details, Biology

Assignment Help:

Describe Fourth Heart Sound in details?

S4 is generated during the atrial-filling phase. It is a low frequency event. LVS, is best heard over apex. Mechanism of S4 generation: It occurs when augmented atrial contraction occurs against relatively stiff ventricle to generate pre systolic ventricular distension so that it can contract with greater force.

Physiological S4 call is heart, in athletes who have physiological hypertrophy. It is rarely heard in normal subjects hence should be considered pathological unless proved otherwise.

Pathological S, is generated in any condition, which reduces ventricular compliances in LVH, acute MR, HOCM or ischaemic heart disease. Almost all patients with MI will have phonocardiographic S, unless they have MS (in which atria is unable to transmit its pressure freely to LV) or atrial infarction.

S4 is not heard in constrictive pericarditis or tamponade because the ventricle is unable to expand at the end of diastole and also the atria may be tethered by constrictive process and therefore, not contract well. S, is not heard in patients with atrial fibrillation, as atrial booster pump is lost.

 


Related Discussions:- Describe fourth heart sound in details

Define glycogenolysis, Define Glycogenolysis Glycogenolysis : degrad...

Define Glycogenolysis Glycogenolysis : degradation of glycogen.

What is an evolutionary tree, What is an evolutionary tree? Is there a prec...

What is an evolutionary tree? Is there a precise evolutionary tree known by science that explains the emergence and origin of every type of living being? Evolutionary tree is t

Describe splitting sequence of s2, Describe Splitting sequence of S 2 ? ...

Describe Splitting sequence of S 2 ? Even though the pulmonary valve closes at about 20 mm Hg and aortic valve at 100 mm Hg, the aortic closure occurs first as the impendence

Gastro epiploic artery and inferior epigastric artery, Gastro Epiploic arte...

Gastro Epiploic artery GEA is seldom used now. Patency has been reported as 94 per cent at one year, 88 per cent at five years and 83 per cell1 at ten years. Inferior Epiga

Define briefly about the conjugated proteins, Define briefly about the Conj...

Define briefly about the Conjugated Proteins? Conjugated proteins are made up of simple proteins combined with a non- proteinous substance. The non-proteinous substance is know

State the enzymes and recombinant dna technology, Enzymes and recombinant D...

Enzymes and recombinant DNA technology Recombinant DNA technology, also called as genetic engineering makes use of a variety of enzymes, particularly restriction endonucleases

Which statements concerning enzymes is false, Which of the following statem...

Which of the following statements concerning enzymes is false? a. They function as catalysts b. The active site of an enzyme has a shape that is specific for its c. Many e

Point and non-point sources, Point and Non-Point Sources The discharg...

Point and Non-Point Sources The discharge of effluents in receiving water body at a specific site are referred to a point sources in contrast to the inflow of pollutants in a

Chest examination of new born, Chest Observe for retraction of the...

Chest Observe for retraction of the intercostal muscle which is indicative of severe respiratory distress (a sign of hyaline membrane  disease).  Inspect the brea

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