Path- Hem DyN I Flashcards
What creates the first heart sound (S1)?
The mitral valve closing (beginning of sytole)
What creates (S2) the second heart sound?
The aortic valve slamming shut
What is the Valve between the R Atrium and the R ventricle?
Trucuspid Valve
What is the valve between the R ventricle and Pulmonary Artery (lungs)
Pulmonary valve
What is the approximate pressure in the pulmonary Artery?
25 mmHg about the same as R ventricle
What is preload?
The ventricular wall tension at the end of diastole just before contraction (sytole)
How is preload measured?
By end diastolic pressure, normally determined by end diastolic blood volume
What is the Frank-Starling mechanism?
The physiologic relationship between end-diastolic volume and force of contraction
What is Afterload?
The resistance the ventricle must overcome to pump out its contents.
What are some common causes of decreasesed ventricular compliance?
- Fibrosis
2. Amyloidosis
What is restrictive cardio myopathy?
When ventricular compliance decreses below the ability of the atrium to fill it normally.
What is dyastolic dysfunction?
Impaired cardiac filling
What is sytolic dysfunction?
Impaired cardiac pumping
What are the usually causes of systolic dysfunction?
Impaired contractility or greatly increased afterload.
What does sytolic function normally affect?
- Decreases amount of blood ejected from the ventricle
- Decreases the stroke volume
- decreases the ejection fraction
Does diastolic dysfunction typically affect EJECTION FRACTION?
NO
What are the five major categories of the factors determining the hearts function as a pump?
- Preload
- Afterload
- contractility
- Compliance
- Heart Rhythm
What is heart failure?
The inability of the heart to pump sufficient blood to meet the needs of the body.
What is the most common cause of Chronic heart failure?
Old myocardial infarctions (ischemic cardiomyopathy)
How does uncontrolled severe hypertension cause heart failure?
By causing severe afterload exceeding the ability of the heart to compensate.
What does aortic stenosis cause?
Increases afterload (increased pressure required to force open stenotic valve) resulting in heart failure
Which pathologies generally lower the ejection fraction?
- Aortic Stenosis
- Severe Hypertension
- Coronary artery disease
Which pathologies generally preserve ejection fraction?
- Left ventricular hypertrophy
- Restrictive cardiomyopathy
- Pericardial disease
What is the most common symptom of heart failure?
Dyspnea
What is the pathophysiology of dyspnea?
LA (pulmonary venous) pressure builds up above 20mmHg causing a transudate of fluid to pass from the congested pulmonary veins to the interstitium creating interstitial edema around bronchioles and alveoli and compressing them increasing the resistance to airflow
What are the two most specific symptoms of Heart failure?
Paroxysmal nocturnal dyspnea and orthopnea
What are the two most common symptoms of HF?
Fatigue and dyspnea
What is the cause of pulmonary crackles?
Associated with pulmonary alveolar edema, over 25mmHg in the pulmonary veins causes passage of transudate into the the airspaces
What are crackles?
These are INSPIRATORY sounds attributed to the popping open of small airways occluded by edema between inspiration.
Where are crackles first heard?
At the base of the lungs where vascular hydrostatic pressure is highest but are heard higher and higher as the conditions worsen
What is wheezing due to HF?
Cardiac Asthma (caused by edema around large areways)
What is the cause of the pathological S3 sound in Adults?
A third heart sound early in diastole dull and low pitched attributed to rapid filling
What is the function of BNP?
It is counterregulatory it causes excretion of sodium and water but also causes vasodilation inhibition of renin secretion and antagonism of Angiotensin II
What can be discerned from the level of BNP?
The level of BNP correlates with the severity of heart failure, elevated BNP helps differentiate from lung disease to HF
How does the left ventricle respond to the increased afterload caused by hypertension?
Concentric hypertrophy
What is the most common cause of HF with preserved ejection fraction?
Hypertension
What is the Gallop associated with Hypertension?
S4 gallop
What is decompensative hypertension associated with?
Impaired left ventricular filling, distolic dysfunction
What generates the S4 sound?
The S4 sound is generated by the vigorous left atrial contraction required to inject blood into a stiffened left ventricle .
What is a summation gallop?
Patients with both an S3 and S4 have tachycardia that so shortens diastole that causes the S3 and S4 sounds to overlap
What tool is useful in distinguishing heart failure due to diastolic dysfunction versus systolic heart failure?
Echocardiography
What treatments beneficial for systolic heart failure are not beneficial for diastolic heart failure?
- Beta Blockers
- ACE inh
- ARBs
- Inotropic agents
What is the most common cause of hypovolemic shock?
- Hemmorhage
- Diarrhea
- Vomiting
What are the four profiles of acute heart failure?
- Profile A Warm and Dry
- Profile B Warm and Wet
- Profile C Cold and Wet
- Profile L Cold and Dry
