Heart Valves Flashcards
What is the most common form of valvular heart disease in Western countries?
Degenerative valve disease
Which disease accounts for the majority of valvular pathology in developing countries?
Rheumatic heart disease
What are the most commonly encountered valvular lesions in western countries?
Aortic stenosis and Mitral regurgitation
Why are MR and AS the most prevalent in western countries?
AS -> d/t calcific disease
MR -> d/t primary causes like degenerative disease
2ndary cause = ischemic heart disease
How do valvular lesions change the normal physiology of the heart?
Cause pressure and/or volume overload causes concentric and/or eccentric hypertrophy
Stenosis of which valves will be affected during systole?
Aortic and pulmonic
Stenosis of which valves will be affected during diastole?
Mitral and tricuspid
Valvular obstruction can be classified as either fixed or dynamic. Describe the difference between the two.
Fixed: Constant degree of obstruction to blood flow throughout the cardiac cycle (AS)
Dynamic: Variable degree of obstruction dependent on the phase of the cardiac cycle (hypertrophic obstructive cardiomyopathy)
Stenotic lesions cause increased pressure proximal to the affected valve (T/F)
True
Regurgitant lesions cause pressure overload (T/F)
False
Volume overload
Volume overload leads to what type of physiological changes?
Chamber dilation and eccentric hypertrophy
List the 3 ways the LV can respond to changes in pressure/volume
- Activation of the Frank-Starling mechanism
- Use of the adrenergic neurohormonal systems
- Chamber remodeling
As cardiac function declines the Frank-Starling curve is shifted to the _____ & _______
right & flattened
Further increases in left heart filling pressures lead to minimal increases in CO
Explain how activation of neurohormonal system effects CO
Increased fluid retention -> activating the Frank Starling law which increases both sarcomere length and contractility
Explain the pathophysiology of ventricular remodeling
Concentric LV remodeling enables ventricle to beat harder.
Eccentric hypertrophy enables ventricles to hold more volume.
Explain a New York Heart Association (NYHA) score of 1
Asymptomatic
Explain a New York Heart Association (NYHA) score of 2
Symptoms with ordinary activity but comfortable at rest
Explain a New York Heart Association (NYHA) score of 3
Symptoms with minimal activity but comfortable at rest
Explain a New York Heart Association (NYHA) score of 4
Symptoms at rest
List the physical exam findings associated with LHF
Pulmonary edema
Dyspnea
Pink-frothy sputum
List the physical exam findings associated with RHF
Dependent edema
ascites
JVD
hepatomegaly
What are the 4 unstable clinical risk factors that may require delay of sx?
- Unstable angina
- Dysrhythmias
- Severe valvular disease
- Decompensated HF
If patient needs emergency sx, you must delay for a full work up to determine extent of valvular disease (T/F)
False
Emergency sx takes precedence
Explain the steps for systematic evaluation of primary valvular dysfunction
- Category of valvular dysfunction (stenosis/insufficiency/mixed)
- Status of LV loading (filling problem or no?)
- Acute vs. chronic
- Cardiac rhythm & effects on diastolic filling time
- LV function (HFrEF vs. HFpEF)
- Secondary effects on pulmonary vasculature & RV function (Pulm HTN)
- HR
- Perioperative anti coagulation