Lecture 7 8/27/24

Question 1

What are the characteristics of M-mode echocardiography?

Answer 1

-“time-motion” echo
-single line of ultrasound
-provides unidimensional view of the heart

Question 2

What are the characteristics of 2D echocardiography?

Answer 2

-lines of ultrasound are transmitted in an arc
-image has a triangular shape
-tomographic image is rapidly updating resulting in illusion of “real time”
-discrete frame rate

Question 3

What is the depth on an echo?

Answer 3

the distance from the transducer

Question 4

What are the characteristics of doppler echo?

Answer 4

-frequency shift results when sound waves are reflected from moving objects
-magnitude of the frequency shift is mathematically related to the velocity of the moving object

Question 5

What is a spectral doppler?

Answer 5

-graph of velocity vs time
-flow toward the transducer is shown above the baseline, while flow away is below the baseline

Question 6

What is doppler color flow?

Answer 6

-color pixels are superimposed on echo image
-blue color is flow away, red color is flow towards
-high velocities cannot be displayed

Question 7

How can mitral valve regurgitation be identified using doppler color flow?

Answer 7

by identifying color originating from the mitral valve when the valve appears closed

Question 8

What are the benefits of using M or 2D echocardiography?

Answer 8

-provides delineation of specific cardiac structures
-allows for quantitative assessment of cardiac structure and evaluation of function

Question 9

What are the benefits of using doppler echocardiography?

Answer 9

-localization of murmur origins
-ability to quantify pressure differences across narrowings in circulation

Question 10

What are the limitations of echocardiography?

Answer 10

-provides relatively little information regarding the consequences of cardiac dysfunction
-chest films are still gold standard for diagnosing left-sided CHF

Question 11

What is TFAST?

Answer 11

thoracic focused assessment with sonography for triage

Question 12

What is blood pressure?

Answer 12

force/area, usually measured in mmHg

Question 13

What are the methods for measuring blood pressure?

Answer 13

direct:
-arterial catheter
indirect:
-doppler-cuff method
-oscillometric method
-photoplethysmography

Question 14

How does systemic hypertension relate to heart disease?

Answer 14

systemic hypertension can cause heart disease, but heart disease can NOT cause systemic hypertension

Question 15

What are the systolic BP values of importance when evaluating for systemic hypertension?

Answer 15

• < 160 mmHg: normal
• > 160 mmHg with target organ damage: indicates presence of hypertension
• between 160 and 180 with no target organ damage: recheck; repeated credible high values may indicate hypertension

Question 16

Which organs are the target of damage with systemic hypertension?

Answer 16

-retinas
-kidneys
-heart

Question 17

What are biomarkers?

Answer 17

objectively determined characteristics that may play a role in diagnosis, risk stratification, and evaluation of disease progression/response to therapy

Question 18

What are the functional roles of natriuretic peptides?

Answer 18

-fluid homeostasis/sodium diuresis
-blood pressure regulation/vasodilation

Question 19

What is the stimulus for natriuretic peptide release?

Answer 19

increases in cardiac stretch

Question 20

What is the diagnostic utility of BNP?

Answer 20

-BNP is released by atrial and ventricular cardiomyocytes in response to increases in ventricular filling pressures
-indicates heart failure state

Question 21

What is the physiology of troponin?

Answer 21

complex of sarcomeric regulator proteins consisting of Tn-I, Tn-C, and Tn-T components

Question 22

What are the diagnostic characteristics of troponin?

Answer 22

-cardiac isoform of Tn-I only occurs in cardiac myocytes
-rises in blood troponin reflect cardiac necrosis or myocardial damage
-Tn-I concentration is used in the diagnosis of acute myocardial infarction (humans)