Author Question: Poor R-wave progression is a phrase used to describe R waves that decrease in size from V1 to V4 . ... (Read 33 times)

danielfitts88 · **on:** Jun 25, 2018

Poor R-wave progression is a phrase used to describe R waves that decrease in size from V1 to V4 . This is often seen in an _____ infarction.

a. anteroseptal
b. anterolateral
c. inferolateral
d. inferoposterior

Question 2

Thin strands of fibrous connective tissue extend from the atrioventricular (AV) valves to the papillary muscles and prevent the AV valves from bulging back into the atria during ventricular systole. These strands are called _____.

a. cardiac cilia
b. Purkinje fibers
c. papillary muscles
d. chordae tendineae

Brenm · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

A
Poor R-wave progression is a phrase used to describe R waves that decrease in size from V1 to V4 . This is often seen in an anteroseptal infarction, but may be a normal variant in young persons, particularly in young women. Other causes of poor R-wave progression include left bundle branch block, left ventricular hypertrophy, and severe chronic obstructive pulmonary disease (particularly emphysema).

Answer to Question 2

D
Chordae tendineae are thin strands of connective tissue. On one end, they are attached to the underside of the AV valves. On the other end, they are attached to small mounds of myocardium called papillary muscles. Papillary muscles project inward from the lower portion of the ventricular walls. When the ventricles contract and relax, so do the papillary muscles. The papillary muscles adjust their tension on the chordae tendineae, preventing them from bulging too far into the atria.