Cardiovascular II
Cardiac Conditions
Cardiac Anatomy
• 4 Chambers
• Walls =
myocardium
• Membranes
endocardium =
inner liner
pericardium =
outer sac
Valves prevent backflow
• tricuspid = Right AtrioVentricular valve
• bicuspid/mitral = Left
Atrio-Ventricular valve
• semilunar= pulmonary
@ base of pulmonary a.
to lungs
• Aortic – between left
ventricle & aorta
Cardiac valves
Cardiac cycle
• 1 heart beat: alternate atrial & ventrical
contractions
• Systole: max contraction of ventricles
• Diastole: max relaxation to fill up
• Vena Cava --- Rt Atrium----Rt Ventricle--Pulmonary a----Lungs---Pulmonary v-----Lt Atrium---Lt Ventricle----Aorta----Brain &
Systemic circulation
Conduction System
• SA node: initiates beat
• AV node: receives &
sends impulse
• Bundle of HIS: sends
impulses to ventricles
• Purkinje fibers: terminal
branches in ventricles
• Vagus n. X= inhibitor;
slows HR via
acetylcholine (rest)
• Sympathetic nerves:
accelerate HR via
epinephrine (fight/flight)
Coronary Artery Disease
• S: brief periods of chest pain (CP) due to O2
insufficiency
angina may last a few minutes
triggers: phys activity, stress, heavy meal
• E: coronary thrombosis 2° atherosclerosis
• T: Nitroglycerine: dilates coronary arteries (4)
immediately - sublingual
lifestyle changes
CABG if severe (70% +) and multiple
blockages & EF 35% or less
• R: same as for atherosclerosis
CABG
Coronay Artery Bypass Graft
• Open heart surgery
• Median sternotomy
• Sternal precautions
for 8-12 weeks - see
handout
• Internal Mammary a.
or Saphenous vein
graft
• 2 – 4 bypasses may
be needed
Angioplasty
• For single artery
partial occlusions
• Balloon tip catheter
inserted into coronary
artery
• Balloon expands to
crush plaque build-up
• Stent placement often
to keep it patent
MI
• S: severe, crushing CP,
may radiate to neck, jaw,
left arm; tight chest band;
N & V, diaphoresis; W =
SOB, anx, wk, palp, indig
• E: occlusion of coronary
artery
• T: chew aspirin & 911
thrombolytics & anticoag
tPA = clotbuster
• R: fam Hx, CAD, angina,
HTN, obesity, etc.
<50% Ejection Fraction;
35% EF needs CABG
Dx: CPK & Troponin enzymes, EKG, Hx
Cardiac Arrest
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Sudden cessation of cardiac circulation=0% EF
No significant heart pumping = 0% BP
No significant electrical heart activity
Flat-line EKG = no PQRST wave, no HR
Collapse – apparent death – need CPR STAT
E: V-fib, severe MI with massive cardiac death,
drowning, suffocation, electrocution, drug
overdose; vital organs receive no circulation
• CPR and defibrillator
Congestive Heart Failure
• Usually develops slowly: cardiac output
unable to meet the demands of the body
• S: SOB, enlarged heart, irregular HR,
tachy- or bradycardia, poor endurance,
fatigue
Rt = ankle edema +, distended neck veins,
enlarged spleen: Rt ventricle weak
Lt = pulmonary edema: Lt ventricle weak
• E: Caused by MI, CAD, damaged heart
valves, HTN, conduction system failures
CHF
CHF Medical Treatment
• Diuretics – control fluid retention and BP
• K+ supplementation & low salt diet
• Digitalis – to ↑ pumping force of heart and
cardiac output
• Will need O2 supplementation eventually
• Watch out for digitalis toxicity – lethargy
and generalized weakness over a few
days – caused by K+ depletion
Cor Pulmonale
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Very serious Rt sided failure
Due to chronic lung disease
Insufficient blood getting to lungs
Severe hypoxemia; pulmonary HTN
Hypertrophy of R ventricle due to ↑ work of
heart
• Need bronchodilators, supplemental O2, &
eventually respirator
Cor Pulmonale
Mitral valve
• Stenosis: narrowed or
rigid, ↓ flow through it
• ↑ resistance L atrium 
L ventricle
• Blood backs up into L
atrium & lungs
• Congested veins in neck
& lungs
• Pulmonary edema
• Poor circulation to body:
cyanosis
• Often 2 Rheumatic HD
Aortic Valve
• Stenosis: narrowed valve
from L ventricle to aorta
limits blood leaving
ventricle
• Blood backs up into L
ventricle
• L ventricle hypertrophies
due to overwork
• ↓ systemic circulation to
body
• ↓ blood to brain from aorta
 syncope
• Atherosclerosis contributes
Valve Insufficiency
• Valve opening too large to
prevent backflow
• Leaking and regurgitation
• Mitral V = blood leaks back
into L atrium with every L
ventricle contraction,
causes congestion in
lungs
• Aortic V = backflow from
aorta back into L ventricle
 overfills & dilates
Rheumatic Heart Disease
• Strep infection causes Rheumatic Fever &
autoimmune reaction in children
• Mitral valve inflamed
• Vegetations develop on valve flaps
• MV stenosis and/or insufficiency results in
CHF with pulmonary edema (PE)
• Blood stasis in atrium leads to thrombus &
PE – need coumadin to prevent
Rheumatic HD
Endocarditis
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Strep infection of tooth, skin, UTI, UResp
Vegetations filled with bacteria break off
Emboli travel through circulation
Go to brain, lung, kidney and infect
Congenital heart defects often affected
Need antibiotics whenever dental work is
done
Heart Block = BBB
• Electrical impulses do
not pass from SA
node to AV node &
bundle of His
• Partial block =
bradycardia results,
decreased ventricle
force, and heart
failure
• Complete block =
need pacemaker
Pacemaker
A-fib and A-flutter
• Rapid atrial contractions result in rapid and
poor ventricle contractions = ↑ HR
• Tachycardia & arrhythmia causes ↓ blood
flow to brain @ times  dizziness
• Due to mitral stenosis, MI, idiopathic, meds,
caffeine
• Beta Blockers to ↓ ventricular rate
• Coumadin to prevent clots & stroke
• Cardioversion (shock) may help
Normal EKG
A-fib
Pacemaker
V-fib
• Most serious arrhythmia
• Chaotic electrical impulses cause
ventricles to quiver instead of contract
• No BP, EF of 0%  cardiac arrest
• Fatal within 4 minutes without CPR
• Need defibrillator to re-start sinus rhythm
• 5 PVC’s in a row can trigger V-fib
V-fib
V-fib
Normal rhythm
Pre Ventricular Contraction
5 PVC’s in a row can trigger V-fib
Diagnostic Procedures
• Auscultation – stethoscope for murmurs (valves)
• EKG – arrhythmias, MI, CAD, valve disease
• Echocardiogram – US record of heart in action:
size, EF, shape, motion of heart valves &
chambers
• Cardiac catheterization – via vein into heart
chambers to analyze cardiac output, pressure,
etc.
• Angiogram/arteriogram – x-ray with dye to show
blockages ( may need CABG)