Monday, December 1, 2008

Monday, December 1, 2008
Cardiovascular infection and Valvular Heart Disease.

Respiratory and GI are most common to be infected. Cardiac infections are uncommon, but are deadly.
Pericarditis: Where the layer surrounding the heart gets infected
Myocarditis: Where the actual muscle gets infected. The nastiest of the three. Weakens the cardiac muscle, can be permenant. Often affecting young people.
Endocarditis: Most common of three,
Causes: 1. viral infections. Enteroviruses are the group of viruses. Don’t cause typical cold.
2. Bacterial infection: strep pneumococcus. Same as pneumonia.
Tuberculosis. Seen in HIV pts.
3. Most common cause of pericarditis is not infection, but uremia: renal failure and people with an elevated BUN.

Symptoms of Pericarditis:
-Chest pain: worsened when lye down and eased when sitting up.
-Hallmark: 100% specificity: pericardial rub. Instead of lub dub, it sounds like two fine pieces of sandpaper rubbing together. Pulse volume will drop, tachycardia, and fever (60%). If they have lots of bleeding, decreased volume of heart tones.
-Mostly mild. 70% of people with it don’t go to Dr.
-ST segment elevation in almost every lead. Caused by more than just heart attacks.
-Chest X ray: heart develops a nice rounded water bottle shape.

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Causes of Myocarditis:
-Lime Disease,
-HIV
-Rheumatic Cardiac disease.

Symptoms of Myocarditis:
-Fatigue: Cardiac output begins to drop very slowly, over months. Ask about exercise: can’t walk as many stairs.
-Chest pain: very vague awareness of heart.
-Fever: least common symptom. Unexplained by anything else.

Diagnose Myocarditis
-Cardiogram. First degree AV block means below 2 seconds to be normal. Time it takes to go from atrium to ventrical is much longer. From P to the QRS wave.
-Echocardiogram: gives a functional reading of cardiac output. Ejection fraction: the average amount of blood ejected by the heart. 2/3 of blood should be pumped out. Good to see if ejection fraction is reduced to to 50% or so, slowing 1/5.
-Biopsy: snip out a piece of heart.

Myocarditis
-the most common cause of transplants in young people.
-Ejection fraction is reduced, even to 10%. Lost most muscular function.
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Risks for Endocarditis:
-most common cardiac infection
-Drug Use
-Abnormal valvular structure: congenital and rheumatic. Anyone with prosthetic valve.
-Even brushing your teeth can cause it. Bacturemia: body is capable of handling a certain amount of bacterial organisms in the blood. Colonization: process of germs being able to adhere to a surface in the endocardial site. Basically undetectable. Vegetation is the next step: where the macroscopic eventuality of the microscopic problem.
-Any previous history of Endocarditis. 9% mortalitiy. CNS embolization is 30% mortality.
Causes of endocarditic:
-Bacterial Staph Aureus. Later becomes MRSA.
-Bacterial Strep
-Enterococcus: comes from GI and urinary tract.
-No viruses cause endocarditic that we know of. It is extremely rare for fungus to be the cause.
Valves affected by endocarditis:
-Mitral: most common in endocarditic: Highest pressure associated with it.
-Tricuspic valve: 60% in some places. Due to IV drug use. First valve germs go through.
-Aortic valve: 20%
-Pulmonic: least common. Less than 5 %
Symptoms of endocarditic
-Fatigue
-Fever: very common: 95%. Fever and fatigue is very common to endocarditic. Sustained. Clnical sign we look for. Absence of any fever would make endocarditic be unlikely.
-Cough: begins developing early . Pulmonary infection
-Weight loss: universal symptom of people with endocarditic.
-Arthritis
-Chest pain: not as common. Not severe. Just an awareness of the heart.
-Dyspnea: almost always.
Clinical signs of endocarditic.
- Heart murmers: new or changing.
-Splenomegally. Spleen ir responsible for cleaning blood.
-Skin lesions: Petechia lesions, little blood dots. Splinter hemorrhages in fingernails. Spots on the surface of retina: Roth spots.
-Enlarged lymph nodes.
-Heart failure.
-Labs: high WBC, decreased RBC, Hematuria. Unexplained proteinuria. Positive blood culture.
-Echocardiogram: look for vegetations and valvular destruction.
Complications of endocarditic:
-Congestive heart failure. 30% of the time.
-CNS embolization: th e most common complication of endocarditic in young people.
-Aneurisms. Dialitation of an arterial segment from weakening of the wall. Happens because infectino eats into arterial wall.
-Valve abscess.
-Renal embolisms failure.




Vena cava, out pulmonary artery and out into lungs.
Stenosis.
Gets noisy: creates all sorts of noises: murmers.
Stenosis: primary chamber hypertrophy.


__VC, RA, t, RV, p, PA, lungs, PV, LA, m, LV, a, A __ to body.
Systolic murmers: characterized by ventricular contraction.
Diastolic murmers: happen by atrial contraction.

If the plutonic valve is steno tic, the valve would have a steno tic murmer.
This valve is partially blocedl. Systole.

If they had tricuspid stenosis, it would be diastolic because the atrial contracts and that’s what makes the noise.

Aortic stenosis is diastolic.


Location:
Pulmonic mermer noise: to the left of the upper sternum. Tricuspic beneath lower sternum. Mitral on the left side of the body. Keep in mind the sequence of blood flow through the heart. Tehne start listening.


Timing of mumer/location/quality of sound.

Pathophysiology of pulmonic stenosis. Where is the murmer. What is the patho physiology? If thy had a really thic pulmonic valve it would be a systolic mermer and it would be located on the L side of the sternum. Left paristernal murmur. The chamber clsoest to that valve which is doing the pumping. Left ventrical if dealing with steno tic pumonic valve would have hypertrophy. Sometimes also right atrial enlargement. Atrium has to fill up the ventral and if it struggling with high pressure situation. Frequently on examination, this is what you pick up.

Aortic stenosis: one of the most common abnormality in adults. Congenital abnormality. If you look at valve from the top, it should have 3 leaflets. Congenitally many people are born with only 2 leaflets and they don’t open up all the way in the first place. A calcify valvular abnormality. Obstruction to ventricular emptying. The murmer is AS and it is located in the right upper paristernal area and beneath the sternum. Then study timing and if it coincides with pulse it is systolic. If it doesn’t coicnicde with pulse then its diastolic. Aortic stenoosis is a diastolic mermer in that location. Left ventricular hypertrophy. LVH. Left atrium can also be invoved because the ventrical is so muscular and taking up so much space. As long as mitral valve doesn’t have backflow, the lungs should be fine. Aortic stenosis is very symptomatic. Early on, they get dizzy. Decreasing cardiac output. Angina can mean very advanced disease. Syncope: probably needs surgery.
Mitral stenosis: not too common. Most common cuase is rheumatic fevrer as a child. Mitral valve becomes really thick and obstructed.
TEST: What is the timing of a mitral stenosis murmer: Diastolic. Atrium pumps blood through diastolic valve. It is located in the person’s Left intercostal space at the apex of the heart.
Pathophysiology: Left atrium is primarily responsible for pumping blood through mitral valve. Thse people get huge muscular left atriums which get ery enlarged. Other parts on this diagrm woud be affected is lungs. Early sign of mitral stenosis is pulmonary edema. A cough that won’t quit because lungs are congested.
Hemopothes: 45 y/o woman who has a cough for months and coughs up blood. Mitral stenosis. Valve gets obstructed. Left atrium hypertrophy and pulmonary symptoms.

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One of most common valvular abnormalities is mitral regurgitation or mitral insufficiency. Happens to alllot of people who are bon with abnormal mitral avles. Common patterns. Patho physiology of mitral regurgitation.






EXAM:
Aortic insufficiency and Aotric regurgitation. Aortic valve won’t close all the way.
Where is murmer and when?
Aortic valve is involved and open. The nature is that once blood gets pumped out of aorta it is going to flow back into the LV because the valve doesn’t close all the way. This happens in diastole. (in systole it is puming things out). So this is a diastolic murmur and it is located in the aortic area. So if you had this person in front of your, you would notice that the pulse would follow the radial pulse. Structural changes: Left ventrical is definitely going to have to enlarge. Left ventrical you are pumping all blood into aorta. This person. Tremendous cardiac outputs. Aorta would become dilated too because it has to accept a large amount of blood. Creates non laminar blood flow with turbulent angles. These people get a very dilated aorta. LA gets dilated beause when that ventrical is emptied and tiis relaxing its getting blood from both ends. So LA must get large to keep the LV filled.

Tricuspid insufficiency: Tricuspid valvular endocarditic. Right atrium is going to be enlarged because allot of blood is being pumped back into it. Neck veins.

Vena Cava, to Right Atrium (diastolic) to tricuspid valve, to Right ventrical (systolic) to pumonic valve to Pulmonary artery. Lungs. Pulmonic Valve to left atrium (diastolic) to Mitral valve to Left ventrical (systolic) to atrium out to the body.
Normal blood flow:
1. One way
2. Unimpeded
3. Silent