650 Section III / Subspecialty Surgery

What are the ways to increase CO?

When does most of the coronary blood flow take place?

Remember “MR. PAIR”:

1.Mechanical assistance (IABP, VAD)

2.Rate—Increase heart rate

3.Preload—Increase preload

4.Afterload—Decrease afterload

5.Inotropes—Increase contractility

6.Rhythm—Normal sinus

During diastole (66%)

Name the three major	1.	Left Anterior Descending (LAD)
coronary arteries.	2.	Circumflex
	3.	Right coronary
What are the three main	1.	Calcium (inotropic)
“cardiac electrolytes”?	2.	Potassium (dysrhythmias)
	3.	Magnesium (dysrhythmias)

ACQUIRED HEART DISEASE

CORONARY ARTERY DISEASE (CAD)

What is it?	Atherosclerotic occlusive lesions of the
	coronary arteries; segmental nature
	makes CABG possible
What is the incidence?	CAD is the #1 killer in the Western
	world; 50% of cases are triple vessel
	diseases involving the LAD, circumflex,
	and right coronary arteries
What are the symptoms?	If ischemia occurs (low flow, vasospasm,
	thrombus formation, plaque rupture, or a
	combination), patient may experience
	chest pain, crushing, substernal shortness
	of breath, nausea/upper abdominal pain,
	sudden death, or may be asymptomatic
	with fatigue
Who classically gets “silent”	Patients with diabetes (autonomic
MIs?	dysfunction)

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What are the risk factors?	HTN
	Smoking
	High cholesterol/lipids ( 240)
	Obesity
	Diabetes mellitus
	Family history
Which diagnostic tests	Exercise stress testing ( thallium)
should be performed?	Echocardiography
	Localize dyskinetic wall segments
	Valvular dysfunction
	Estimate ejection fraction
	Cardiac catheterization with coronary
	angiography and left ventriculography
	(the definitive test)
What is the treatment?	Medical therapy ( -blockers, aspirin,
	nitrates, HTN medications), angioplasty
	(PTCA), stents, surgical therapy: CABG
CABG
What is it?	Coronary Artery Bypass Grafting
	Vein
	grafts

	2
	0
	'
	f
	r
	h
What are the indications?	Left main disease
	2-vessel disease (especially diabetics)
	Unstable or disabling angina unresponsive
	to medical therapy/PTCA
	Postinfarct angina
	Coronary artery rupture, dissection,
	thrombosis after PTCA

652 Section III / Subspecialty Surgery
CABG vs. PTCA stents?	CABG Survival improvement for
	diabetics and 2-vessel disease,
	c short-term morbidity
	PTCA T short-term morbidity, T cost,
	T hospital stay, c reintervention,
	c postprocedure angina
What procedures are most	Coronary arteries grafted (usually 3–6):
often used in the treatment?	internal mammary pedicle graft and
	saphenous vein free graft are most often
	used (IMA 95% 10-year patency vs. 50%
	with saphenous)
What other vessels are	Radial artery, inferior epigastric vein
occasionally used for
grafting?
What are the possible	Hemorrhage
complications?	Tamponade
	MI, dysrhythmias
	Infection
	Graft thrombosis
	Sternal dehiscence
	Postpericardiotomy syndrome, stroke

What is the operative mortality?

What medications should almost every patient be given after CABG?

1% to 3% for elective CABG (vs. 5%–10% for acute MI)

Aspirin, -blocker

Can a CABG be performed off cardiopulmonary bypass?

Yes, today they are performed with or without bypass

POSTPERICARDIOTOMY SYNDROME

What is it?	Pericarditis after pericardiotomy
	(unknown etiology), occurs weeks to
	3 months postoperatively
What are the signs/	Fever
symptoms?	Chest pain, atrial fibrillation
	Malaise
	Pericardial friction rub
	Pericardial effusion/pleural effusion

What is the treatment?

What is pericarditis after an MI called?

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NSAIDs, / steroids

Dressler’s syndrome

CARDIOPULMONARY BYPASS (CPB)

What is it?	Pump and oxygenation apparatus remove
	blood from SVC and IVC and return it to
	the aorta, bypassing the heart and lungs
	and allowing cardiac arrest for open-heart
	procedures, heart transplant, lung
	transplant, or heart-lung transplant
	as well as procedures on the proximal
	great vessels

Is anticoagulation necessary?

How is anticoagulation reversed?

What are the ways to manipulate cardiac output after CPB?

What mechanical problems can decrease CO after CPB?

What is “tamponade physiology”?

Yes, just before and during the procedure, with heparin

Protamine

Rate, rhythm, afterload, preload, inotropes, mechanical (IABP and VAD)

Cardiac tamponade, pneumothorax

T Cardiac output, c heart rate, hypotension, c CVP c wedge pressure

654 Section III / Subspecialty Surgery
What are the possible	Trauma to formed blood elements
complications?	(especially thrombocytopenia and
	platelet dysfunction)
	Pancreatitis (low flow)
	Heparin rebound
	CVA
	Failure to wean from bypass
	Technical complications (operative
	technique)
	MI

What are the options for treating postop CABG mediastinal bleeding?

What is “heparin rebound”?

Protamine, c PEEP, FFP, platelets, aminocaproic acid

Increased anticoagulation after CPB from increased heparin levels, as increase in peripheral blood flow after CPB returns heparin residual that was in the peripheral tissues

What is the method of lowering SVR after CPB?

What are the options if a patient cannot be weaned from CPB?

What percentage of patients goes into AFib after CPB?

What is the workup of a postoperative patient with AFib?

What is a MIDCAB?

Warm the patient; administer sodium nitroprusside (SNP) and dobutamine

Inotropes (e.g., epinephrine)

VAD, IABP

Up to 33%

Rule out PTX (ABG, CT scan), acidosis (ABG), electrolyte abnormality (LABS), and ischemia (EKG), CXR

Minimally Invasive Direct Coronary Artery Bypass—LIMA to LAD bypass without CPB and through a small thoracotomy

What is TMR?	TransMyocardial laser Revascularization:
	laser through groin catheter makes small
	holes (intramyocardial sinusoids) in
	cardiac muscle to allow blood to nourish
	the muscle

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What is OPCAB?	Off Pump Coronary Artery Bypass—
	median sternotomy but no bypass pump
AORTIC STENOSIS (AS)
What is it?	Destruction and calcification of valve
	leaflets, resulting in obstruction of left
	ventricular outflow
What are the causes?	Calcification of bicuspid aortic valve
	Rheumatic fever
	Acquired calcific AS (7th to 8th decades)

What are the symptoms?

What is the memory aid for the aortic stenosis complications?

What are the signs?

Angina (5 years life expectancy if left untreated)

Syncope (3 years life expectancy if left untreated)

CHF (2 years life expectancy if left untreated)

Often asymptomatic until late

Aortic Stenosis Complications Angina

Syncope CHF—5,3,2

Murmur: crescendo-decrescendo systolic second right intercostal space with radiation to the carotids

Left ventricular heave or lift from left ventricular hypertrophy

What tests should be	CXR, ECG, echocardiography
performed?	Cardiac catheterization—needed to plan
	operation
What is the surgical	Valve replacement with tissue or
treatment?	mechanical prosthesis
What are the indications for	If patient is symptomatic or valve cross-
surgical repair?	sectional area is 0.75 cm2 (normal 2.5
	to 3.5 cm2) and/or gradient 50 mm Hg
What are the pros/cons of	Mechanical valve is more durable, but
mechanical valve?	requires lifetime anticoagulation

656 Section III / Subspecialty Surgery
What is the treatment option	Balloon aortic “valvuloplasty”
in poor surgical candidates?	(percutaneous)
Why is a loud murmur often	Implies a high gradient, which indicates
a good sign?	preserved LV function
Why might an AS murmur	It may imply a decreasing gradient from
diminish over time?	a decline in LV function
AORTIC INSUFFICIENCY (AI)
What is it?	Incompetency of the aortic valve
	(regurgitant flow)
What are the causes?	Bacterial endocarditis (Staphylococcus
	aureus, Streptococcus viridans)
	Rheumatic fever (rare)
	Annular ectasia from collagen vascular
	disease (especially Marfan’s syndrome)
What are the predisposing	Bicuspid aortic valve, connective tissue
conditions?	disease
What are the symptoms?	Palpitations from dysrhythmias and
	dilated left ventricle
	Dyspnea/orthopnea from left ventricular
	failure
	Excess fatigue
	Angina from T diastolic BP and coronary
	flow (Note: Most coronary blood flow
	occurs during diastole and aorta
	rebound)
	Musset sign (bobble-head)
What are the signs?	c diastolic BP
	Murmur: blowing, decrescendo diastolic
	at left sternal border
	Austin-Flint murmur: reverberation of
	regurgitant flow
	Increased pulse pressure: “pistol shots,”
	“water-hammer” pulse palpated
	over peripheral arteries
	Quincke sign (capillary pulsations of
	uvula)

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Which diagnostic tests	1.	CXR: increasing heart size can be
should be performed?		used to follow progression
	2.	Echocardiogram
	3.	Catheterization (definitive)
	4.	TEE
What is the treatment?	Aortic valve replacement
What are the indications for	Symptomatic patients (CHF, PND, etc.),
surgical treatment?	left ventricle dilatation, decreasing LV
	function, decreasing EF, acute AI onset
What is the prognosis?	Surgery gives symptomatic improvement
	and may improve longevity; low operative
	risk
MITRAL STENOSIS (MS)
What is it?	Calcific degeneration and narrowing of
	the mitral valve resulting from rheumatic
	fever in most cases
What are the symptoms?	1.	Dyspnea from increased left atrial
		pressure, causing pulmonary edema
		(i.e., CHF)
	2.	Hemoptysis (rarely life-threatening)
	3.	Hoarseness from dilated left atrium
		impinging on the recurrent laryngeal
		nerve
	4.	Palpations (AFib)
What are the signs?	Murmur: crescendo diastolic rumble at apex
	Irregular pulse from AFib caused by
		dilated left atrium
	Stroke caused by systemic emboli from
		left atrium (AFib and obstructed valve
		allow blood to pool in the left atrium
		and can lead to thrombus formation)
Which diagnostic tests	Echocardiogram
should be performed?	Catheterization
What are the indications for	1.	Symptoms (severe)
intervention?	2.	Pulmonary HTN and mitral valve area
		1 cm2/m2
	3.	Recurrent thromboembolism

658 Section III / Subspecialty Surgery
What are the treatment	1.	Open commissurotomy (open heart
options?		operation)
	2.	Balloon valvuloplasty: percutaneous
	3.	Valve replacement
What is the medical	Diuretics
treatment for mild
symptomatic patients?
What is the prognosis?	80% of patients are well at 10 years
	with successful operation
MITRAL REGURGITATION (MR)
What is it?	Incompetence of the mitral valve
What are the causes?	Severe mitral valve prolapse (some
		prolapse is found in 5% of the
		population, with women men)
	Rheumatic fever
	Post-MI from papillary muscle
		dysfunction/rupture
	Ruptured chordae
What are the most common	Rheumatic fever (#1 worldwide), ruptured
causes?	chordae/papillary muscle dysfunction
What are the symptoms?	Often insidious and late: dyspnea,
	palpitations, fatigue
What are the signs?	Murmur: holosystolic, apical radiating to
	the axilla
What are the indications for	1.	Symptoms
treatment?	2.	LV 45 mm end-systolic dimension
		(left ventricular dilation)
What is the treatment?	1.	Valve replacement
	2.	Annuloplasty: suture a prosthetic ring
		to the dilated valve annulus

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ARTIFICIAL VALVE PLACEMENT

What is it?

What are the types of artificial valves?

What are the pros and cons: Tissue?

Replacement of damaged valves with tissue or mechanical prosthesis

Tissue and mechanical

NO anticoagulation but shorter duration (20%–40% need replacement in 10 years); good for elderly

Mechanical?

Contraindications for tissue valve?

Contraindications for mechanical valve?

What is the operative mortality?

What must patients with an artificial valve receive before dental procedures?

Last longer ( 15 years) but require ANTICOAGULATION

Dialysis (calcify), youth

Pregnancy (or going to be pregnant due to anticoagulation), bleeding risk (alcoholic, PUD)

From 1% to 5% in most series

Antibiotics

Define the Ross procedure.	Aortic valve replacement with a pulmonary
	autograft (i.e., patient’s own valve!)
INFECTIOUS ENDOCARDITIS
What is it?	Microbial infection of heart valves
What are the predisposing	Preexisting valvular lesion, procedures
conditions?	that lead to bacteremia, IV drug use
What are the common	S. viridans: associated with abnormal
causative agents?	valves
	S. aureus: associated with IV drug use
	S. epidermidis: associated with prosthetic
	valves