• Group of syndromes related to myocardial ischemia

• IHD is the leading cause of death in the US
• Usually due to atherosclerosis of coronary arteries, which decreases blood flow to the myocardium
• Risk factors are similar to those of atherosclerosis; incidence increases with age

• Chest pain that arises with exertion or emotional stress
• Due to atherosclerosis of coronary aa with >70% stenosis; decreased blood flow is not able to meet the metabolic demands of the myocardium during exertion
• Represents reversible injury to myocytes (no necrosis)
• Presents as chest pain (lasting <20minutes) that radiates to the left arm or jaw, diaphoresis, and shortness of breath
• EKG shows ST-segment depression due to subendocardial ischemia
• Relieved by rest or nitroglycerin

• Chest pain that occurs at rest
• Usually due to rupture of an atherosclerotic plaqye with thrombosis and incomplete occlusion of a coronary artery
• Represents reversible injury to myocytes (no necrosis)
• EKG shows ST-segment depression due to subendocardial ischemia
• Relieved by nitroglycerin
• Hgh risk of progression to myocardial Infarction

• Episodic chest pain unrelated to exertion
• Due to coronary artery vasospasm
• Represents reversible injury to myocytes (no necrosis)
• EKG shows ST segment elevation b/c of transmural ischemia
• Relieved by nitroglycerin or calcium channel blockers

• Necrosis of cardiac myocytes
• Usually due to rupture of an atherosclerotic plaque with thrombosis and complete occlusion of a coraonary artery
• Other causes include coronary artery vasospasm (due to Prinzmetal angina or cocaine use), emboli, and vasculitis (ex Kawasaki disease)
• Clinical features include severe, crushing chest pain (lasting >20 minutes) that radiates to the left arm or jaw, diaphoresis, and dyspnea; symptoms are not relieved by nitroglycerin
• Infarction usually invlves the left ventricle (LV); right ventricle (RV) and both atria are generally spared

• leads to infarction of the anterior wall and anterior septum of the LV
• LAD is the most commonly involved artery in MI

• Infarction of the posterior wall
• Posterior septum
• Papillary muscles of the LV
• RCA is the 2nd most commonly involved artery in MI

• Infarction of lateral wall of the LV

• leads to subendocardial necrosis involving <50% of the myocardial thinckness (subendocardial infarction)
• EKG shows ST segment depression
• Continued or severe ischemia leads to transmural necrosis involving most of the myocardial wall (transmural infarction)
• EKG shows ST segment elevation

• Detect elevated cardiac enzymes
• Troponin I is the most sensitive and specific marker (gold standard ) for MI
• Levels rise 2-4 hours after infarction, peak at 24 hours and return to normal by 7-10 days
• CK-MB is useful for detecting reinfarction that occurs days after an intitial MI; Creatine kinase MB (CK-MB) levels rise 4-6 hours after infarction, peak at 24 hours, and return to normal by 72 hours

• Aspirin and/or heparin-limits thrombosis
• Supplemental O2-minimizes ischemia
• Nitrates-vasodilate coronary arteries
• Beta blocker-slows hear rate, decreasing O2 deman and risk for arrhythmia
• ACE inhibitor-decreases LV dilation
• Fibrinolysis or angioplasty-opens blocked vessel-reperfusion of irreversibly-damaged cells results in calcium influx, leading to hypercontraction of myofibril (contraction band necrosis
• Return of oxygen and inflammatory cells may lead to free radical generation, further damaging myocytes (reperfusion injury)

• Unexpected death due to cardiac disease; occcurs w/o symptoms or <1 hour after symptoms aris
• Usually due to fatal ventricular arrhytmia
• Most comon etiology is acute ischemia; 90% of patients have preexisting severe atherosclerosis
• Less common=mitral valve prolasps, cardiomyopathy, and cocaine abuse

• Poor myocardial function b/c of chronic ischemic damage (w/ or w/o infarction); progresses to congestive heart failure (CHF)

• Pump failure; divided into right- and left sided failure

• Causes include ischemia, HTN, dilated cardiomyopathy, myocardial infarction, and restrictive cardiomyopathy
• Clinical features are due to decreased forward perfusion and pulmonary congestion
• Pulmonary congestion-->pulmonary edema
• Results in dyspnea, paroxysmal nocturnal dyspnea (due to increased venous return when lying flat), orthopnea, and crackles
• Small, congested capillaries may burst, leading to intraalveola hemorrhage; marked by hemosiderin-laden macrophages (heart-failure cells)
• Decreased flow to kidneys leads to activation of RAAS
• fluid retention exacerbates CHF
• Mainstay of treatment is ACE inhibitor

• Most commonly due to left-sided heart failure; other important causes are left-right shunt and chronic lung disease (cor pulmonale)
• Clin. features are due to confestion
• Jugular venous distension
• Painful hepatosplenomegaly w/ char. nutmeg liver; may lead to cardiac cirrhosis
• Dependent pitting edema (due to increased hydrostatic pressure)

• Arise during embryogenesis (usually weeks 3-8); seen in 1% of live births
• Most defects are sporadic
• Often result in shunting between left (systemic) and right (pulmonary) circulations/
• Defects w/ left-->right shunting may be relatively asymptomatic at birth, but the shunt can eventually reverse
• Increased flow through the pulmonary circulation results in hypertrophy of pulmonary vessels and pulmonary HTN
• Increased pulmonary resistance eventually results in reversal of shunt, leading to late cyanosis (Eisenmenger syndrome) w/ Right ventricular hypertrophy, polycythemia, and clubbing
• Defects w/ r-->L shunting usually present as cyanosis shortly after birth

• Defect in the septum that divides the right and left ventricles
• Most common congenital hear defect
• Associated w/ fetal alcohol syndrome
• Results in left-->right shung; size of defect determines extent of shunting and age at presentation.  Small defects are often asymptomatic; large defects can lead to Eisenmenger syndrome
• Treatment involves surgical closure; small defects may close spon.

• Defect in the septum that divides right and left atria; most common type is ostium secundum (90% of cases)
• Ostium primum is assoc. w/ Down Syndrome
• Results in left to right shunt and split S2 on auscultation (increased blood in right heart delays closure of pulmonary valve)
• Paradoxical emboli are an important complication

• Failure of ductus arteriosus to close; associated w/ congenital rubella
• Results in left-right right btw the aorta and the pulmonary artery
• During development the ductus arteriosus normally shunts blood from the pulmonary artery to the aorta, bypassing the lungs
• Asymptomatic at birth with holosystolic "machine-like" murmur; may lead to Eisenmenger syndrome, resulting in lower extremity cyanosis
• Treatment involves indomethacin, which decreases PGE, resulting in PDA closure (PGE maintains patency of the ductus arteriosus)

• Char. by 1)stenosis of the right ventricular outflow tract
• 2) Right ventricular hypertrophy
• 3) VSD
• 4) an aorta that overrides the VSD
• RIght-->left shunt leads to early cyanosis; degree of stenosis determines the extent of shunting and cyanosis
• Patients learn to squat in response to a cyanotic spell; increased arterial resistance decreases shunting and allows more blood to reach the lungs
• Boot shaped heart on X-ray

• Char. by pulmonary artery arising from the left ventricle and aorta arising from the right ventricle
• Associated with maternal diabetes
• Presents w/ early cyanosis; pulmonary and systemic circuits do not mix
• Creation of shunt (allowing blood to mix) after birth is required for survival
• PGE can be admin to maintain a PDA until definitive surgical repair is performed
• Results in hypertrophy of the right ventricle and atrophy of the left ventricle

• Char. by a single large vessel arising from both ventricles
• Truncus fails to divide
• Presents with early cyanosis; deoxygenated blood from right ventricle mixes with oxygenated blood from left ventricle before pulmonary and aortic circulations separate

• Tricuspid valve orifice fails to develop; right ventricle is hypoplastic
• Often associated w/ ASD, resulting in a right-->left shunt; presents with early cyanosis

• Narrowing of the aorta, classically divided into infantile and adult forms
• infantile form is associated w/ a PDA; coarttation lies after (distal to) the aortic arch, but before (proximal to ) the PDA.
• Presents as lower extremity cyanosis in infants, often at birth
• associated w/ turner syndrome
• Adult form is not associated w/ a PDA; coarctation lies after (distal to) the aortic arch
• presents as HTN in the upper extremities and hypotension with weak pulses in the lower extremities; classically discovered in adulthood
• collateral circulation develops across the intercostal arteries; engorged arteries cause 'notching' of ribs on x-ray
• Associated w/ bicuspid aortic valve

• The heart has 4 valves (tricuspid, pulmonary, mitral, and aortic) that prevent backflow
• valvular lesions generally result in stenosis (decreased caliber of the valve orifice) or regurgitation (backflow)

• Systemic complication of pharyngitis due to group A beta-hemolytic streptococci; affects children 2-3 weeks after an episode of streptococcal pharyngitis ("strep throat")
• Caused by molecular mimicry; bacterial M protein resembles proteins in human tissue
• Diagnosis is based on Jones criteria
• Evidence of prior group A beta hemolytic streptococcal infection (ex elevated ASO or anti-DNase b titers) with the presence of major and minor criteria
• minor criteria are nonspec. and include fever and eelevated ESR
• Major criteria

1. Migratory polyarthritis-swelling and pain in a large joint (ex wrist, knees, ankles) that resolves w/i days and migrates to involve another large joint
2. pancarditis

• endocarditis-mitral valve is involved more commonly that the aortic valve.  Char. by small vegetations along lines of closeure that lead to regurgitation
• Myocarditis w/ Aschoff bodies that are char. by foci of chronic inflammation, reactive histiocytes w/ slender, wavy nuclei (Anitschkow cells), giant cells, and fibrinoid material; myocarditis is the most common cause of death during the acute phase
• Pericarditis- leads to friction rub and chest pain

1. sub cutaneous nodules
2. Erythema nodules
3. Erythema marginatum-annular, non-pruritic rash w/ erythematous borders, commonly involving trunk and limbs
4. Syndenham chorea (rapid, involunatary muscle movements)

• Acute attack usually resolves but may progress to chronic rheumatic heart disease; repeat exposure to group A Beta hemolytic streptococci results in a relapse of the acute phase and increases risk for chronic disease

• Valve scarring that arises as a consequence of rheumatic fever
• results in stenosis w/ a classic fish-mouth appearance
• almost always involves the mitral valve; leads to thickening of chordae tendineae and cusps
• occaisonally involves the aortic valve; leads to fusion of the commissure
• other valves are less commonly involved
• complications include infectious endocarditis

• Narrowing of the aortic valve orifice
• Usually due to fibrosis and calcification from "Wear and tear"
• presents in late adulthood >60 years
• bicuspid aortic valve increases risk and hastens disesease onset.  A normal aortic valve has 3 cusps; fewer cusps results in increased "wear and tear" on each cusp
• May also arise as a consequence of chronic rheumatic valve disease; coexisting mitral stenosis and fusion of the aortic valve commissures distinguish rheumatic disease from "wear and tear"
• Cardiac compensation leads to a prolonged asymptomatic stage during which a systolic ejection click followed by a crescendo-decreascendo murmur is heard

Complications:

1. concentric left ventricular hypertrophy-may progress to cardiac failure
2. angina and syncope with exercise-limited ability to increase blood glow across teh stenotic valve leads to decreased perfusion of the myocardium and brain.
3. Microangiopathic hemolytic anemia-RBCs are damaged (prod. schistocytes) while crossing the calcified valve.
4. Treatment is valve replacement after onset of complications

• Backflow of blood from the aorta into the left venticle during diastole
• arises due to arotic root dilation (ex symphilitic aneurysma dn aortic dissection) or valve damage (Ex infectious endocarditis); most common cause is isolated root dilation
• Clinical features:

1. early, blowing diastolic murmur
2. hyperdynamic circulation b/c of increased pulse pressure
3. PUlse pressure=difference between systolic and idastolic pressures
4. Diastolic pressure decreases due to regurgitation, while systolic pressure increases due to increased stroke volume
5. presents with a bounding pulse (water-hammer pulse), pulasting nail bed, and head bobbing
6. results in LV dialtion and eccentric hypertrophy (b/c of volume overload)
7. Treatment=vavle replacement once LV dysfunction develops

• ballooning of mitral valve into left atrium during systole
• seen in 2-3% of US adults
• Due to myxoid degen (accum. of ground substance) of the valve, making it floppy
• Etiology is unknown; may be seen in Marfan syndrome or Ehlers-Danlos syndrome
• presents w/ an incidental mid-systolic click followed by a regurgitation murmu; usually asymptomatic
• click and murmur become louder w/ squatting (increased systemic resistance decreased left ventricular emptying)
• complication are rare, but include infectious endocarditis, arrhythmia, and severe mitral regurgitation
• Treatment is valve replacement

• Reflux of blood from the left ventricle into the left atrium during systole
• usually arises as a complication of mitral valve prolapse; other causes include LV dilatation (ex left-sided cardiac failure), infective endocarditis, acute rheumatic heart disease, and papillary muscle rupture afte a MI
• Holosystolic "blowing" murmur; louder w/ squatting (increased systemic resistance decreases left ventricular emptying) and expiration (increased return to left atrium)
• results in volume overload and left-sided heart failure

• Narrowing of the mitral valve orifice
• usually due to chronic rheumatic valve disease
• opening snap followed by diastolic rumble
• volume overload-->dilatation of the left atrium, resulting int

1. Pulmonary congestion with edema and alveolar hemorrhage
2. Pulmonry htn and eventual right-sided heart failure
3. Atrial fibrillation w/ associated risk for mural thrombi

• Inflammation of endocardium that lines the surface of cardiac valves; usually b/c of bacterial infection
• streptococcus viridans is the most common overall cause. (it is a low virulence organism that infects previously damaged valves)
• Ex chronic rheumatic Heart disease and mitral valve prolaps
• Results in small vegetations that do no destroy the valve (subacute endocarditis)
• damaged endocardial suface develops thrombotic vegetations (platelets and fibrin)
• transient bacteremia leads to trapping of bacteria in teh vegetations
• prophylactic antibiotics decrease risk of endocarditis

• most common cause of endocarditis in IV drug busers
• High virulence organism that infects normal valve, most commonly the tricuspid
• Results in Large vegetations that destroy the valve

• Associated with endocarditis in patients with underlying colorectal carcinoma

1. Fever-b/c of bacteremia
2. Murmur-b/c of vegetations on heart valve
3. Janeway lesions-erythemeatous nontender lesions on palms and soles), Osler nodes (tender lesions on fingers or toes), and splinter hemorrhages in nail bed-due to embolization of septic vegetations
4. Anemia of chronic disease-due to chronic inflammation

• Positive blood cultures
• Anemia of Chronic disease (decreased Hb, decreased MCV; increased ferritin, decreased TIBC, decreased serum iron, and decreased % saturation
• Transesophageal echocardiogram=useful for detecting lesions on valves

• Due to sterile vegetations that arise is association w/ a hypercoagulable state or underlying adenocarcinoma.
• Vegetations arise on the mitral valve along lines of closure and result in mitral regurgitation

• Due to sterile vegetations that arise in association w/ SLE.
• Vegetations are present on the surface and undersurface of the mitral valve and result in mitral regurgitation

• group of myocardial diseases that result in cardiac dysfunction

• dilation of all four chambers of the hear; most common form of cardiomyopathy
• Results in systolic dysfunction (ventricles cannot pump), leading to biventricular CHF; complications include mitral and tricuspid valve regurgitation and arrhythmia

Causes

• Most commonly Idiopathic
• Genetic mutation (usually autosomal dominant)
• Myocarditis (usually due to coxsackie A or B)- char. by a lymphocytic infiltrate in the myocardium; results in chest pain; arrhythmia w/ sudden death, or heart failure.  Dilated cardiomyopathy is a late complication
• Alcohol abuse
• drugs (ex. doxorubicin)
• Pregnancy-seen during late pregnancy or soon (weeks to months) after childbirth
• Treatment is heart transplant

• Massive hypertrophy of the left ventricle
• Usually due to genetic mutations in sarcomere proteins; most common form is autosomal domingant

Clinical Features:

• Decreased cardiac output-left ventricular hypertrophy leads to diastolic dysfunction (ventricle cannot fill)
• Sudden death due to ventricular arrhythmias; hypertrophic cardiomyopathy is a common cause of sudden death in young athletes
• Syncope with exercise- subaortic hypertrophy of the ventricular septum results in functional aortic stenosis
• Biopsy shows mmyofiber hypertrophy with disarray

• Decreased compliance of the ventricular endomyocardium that restricts filling during diastole
• Causes include:
• Amyloidosis
• sarcoidosis
• hemochromatosis
• endocardial fibroelastosis (kids)
• Loeffler syndrome (endomyocardial fibrosis with an eosinophilic infiltrate and eosinophilia)
• Presents as CHF; classic finiding is low-voltage EKG with dimiinshed QRS amplitude

• Benign mesenchymal tumor with a gelatinous appearance and abundant ground substance on histology
• most common primary cardiac tumor in adults
• usually forms a pedunculated mass in the left atrium that causes syncope due to obstruction of the mitral valve

• benign hamartoma of cardiac muscle
• most common primary cardiac tumor is kids; associated w/ tuberous sclerosis
• usually arises in the ventricle

• metastatic tumors are more common in the heart than primary tumors
• common metastases to the heart include breast and lung carcinoma, melanoma, and lymphoma
• most commonly involve the pericardium, resulting in a pericardial effusion