- Chronic hemodynamic stress
- - Endothelial cells leak plasma proteins.
- - Smooth muscle cell matrix synthesis.
- - Pink hyaline thickening narrows lumen
- - Hypertension
- - Elderly persons
- - Diabetic microangiopathy
- - Nephrosclerosis
- Under severe hypertension
- Smooth muscle proliferation, basement membrane and fibrin deposition
- “Onion-skin lesions"
- - Concentric, layered thickening with luminal narrowing.
- +/ - vessel wall necrosis (necrotizing arteriolitis).
- Left-sided hypertensive heart disease
- left ventricle hypertrophy, increased LV wall thickness, stiffness, and heart weight, impaired diastolic filling, minor enlarged left atrium.
- Increased myocyte diameter (early), nuclear enlargement (late)
- Right-sided HHD, Cor pulmonale
- Acute - following massive pulmonary embolism, right ventricular dilation.
- Chronic - right ventricular hypertrophy AND dilation
- Response to pressure overload
Disorders Predisposing to Cor Pulmonale
- DISEASES OF THE PULMONARY PARENCHYMA
- DISEASES OF THE PULMONARY VESSELS
- DISORDERS AFFECTING CHEST MOVEMENT
- DISORDERS INDUCING PULMONARY ARTERIAL CONSTRICTION
- Degenerative disease of large and medium sized arteries.
- Atherosclerotic plaques - Intimal lesions protrude into and narrow the vessel lumen.
Risk factors for atherosclerosis
- Increasing Age
- Male gender
- Family history
- Genetic abnormalities
- Cigarette smoking
- C-reactive protein
Atherosclerosis Risk factors' role in endothelial injury
hypercholesterolemia -> premature atherosclerosis; Predominant lipids in plaques, increase local O2 free radicals
Endothelial Injury - Lipids
- Oxidation of LDL occurs in the arterial wall when exposed to nitric oxide, macrophages, and some enzymes such as lipoxygenase.
- Oxidized LDL is :
- •Cytotoxic to endothelial cells causing
- –dysfunction and leukocyte adhesion causing
- –stimulation of endothelial cells and macrophages activation causing
- –release of growth and chemotaxic factors causing
- –smooth muscle proliferation and monocyte recruitment.
- •ingested by macrophages which
- –become foam cells
- –undergo apoptosis releasing free lipids into the intima.
Endothelial Injury - Hemodynamic Disturbances
- Sites of turbulence
- - Ostia
- - Branch points
- - Posterior wall of abdominal aorta
Chronic Endothelial Injury
Begins at sites of intact endothelium
Endothelial Dysfunction when Injured
- produce Chemotactic factors to attract leukocytes.
- produce Cell surface adhesion molecule (VICAM 1) -> Leucocyte adhesion and emigration.
- change shape -> increased permeability -> cell, platelet and lipid migrate into the intimal space.
Pathogenesis of atherosclerosis
- Monocytes migrating into the intima transform into macrophages and engulf lipoproteins including oxidized LDL -> apoptosis -> liberating free lipid
- T lymphocytes elaborate cytokines and growth factors
Smooth muscle cell recruitment and macrophage activation
- Growth factors -> smooth muscle cell (SMC) proliferation -> extracellular matrix (collagen) synthesis -> atherosclerotic plaques stabilized, fibrofatty atheroma
- Activated inflammatory cells -> SMC apoptosis -> increased ECM catabolism -> unstable plaques
Response to injury hypothesis - atherosclerosis pathogenesis
- Endothelial cell injury
- Macrophage migration
- Lipid accumulation
- Smooth muscle proliferation
- Role of infection
Causes of injury
- Hemodynamic turbulence
- Infectious agents
Infections may drive the inflammatory process
- Herpes, cytomegalovirus, and Chlamydia pneumoniae
- detected in atherosclerotic plaques, not normal arteries
- Increased antibody titers to C. pneumoniae in patients
- with severe atherosclerosis.
- Association with periodontal disease.
- Possible mechanisms:
- - Infect sites of early atheroma formation.
- - Drive local immune responses.
- - Add to local prothrombotic state.
- Foamy lipid-filled macrophages infiltrate the vessel wall.
- Multiple minute flat yellow spots coalesce into linear streaks.
- Earliest lesions - Virtually all children > 10 years; Minimally raised, no flow disturbance
- •Yellow to grey plaques.
- •0.3 to 1.5 cm in diameter - coalesce into masses.
- •Patchy, eccentric, asymmetry, a result of local hemodynamics
- •Thrombus over ulcerated plaques is red-brown.
Anatomy of an atheroma
- Necrotic lipid core - Lipid, foam cells, fibrin, thrombus, cholesterol crystal
- Superficial fibrous cap - Smooth muscle cells, lymphocytes, collagen, elastin, proteoglycans. Neovascularization.
- Shoulder - MPGs, T cells, and SMCs.
Consequences of atherosclerotic disease
- Major targets
- •Large elastic arteries -aorta, carotid, and iliac arteries
- •Large and medium-sized muscular arteries coronary and popliteal.
- Major consequences - Myocardial Infarct, cerebral infarct, aortic aneurysms, and peripheral vascular disease - aneurysm and rupture, occlusion by thrombus, critical stenosis.
- Outcome depends on:
- •Size of the vessels.
- •Stability of the plaque.
- •Degree of degeneration of arterial wall.
- More likely to rupture
- Large areas of foam cells and extracellular lipid
- Fibrous caps are thin or contain few smooth muscle cells - Clusters of inflammatory cells.
- continuously remodeled.
- Collagen-synthesis versus degradation affects cap stability.
- Plaque inflammation increases degradation and reduces synthesis of collagen, destabilizing the fibrous cap.
- Healing plays role in the growth of atheromata
Acute plaque changes
- Rupture; fissuring; erosion; ulceration; thrombosis
- Plaque hemorrhage - Further plaque disruption.
- Probably common, repetitive, and often clinically silent.
- Severe concentric lesions- no longer respond to vasodilators.
- Small arteries - occlude vessel lumina, compromise blood flow, and cause ischemic injury.
- Critical stenosis - significantly limits flow, and demand begins exceeding supply. 70% fixed occlusion
- Patients develop chest pain on exertion (stable angina).
- Bowel ischemia; ischemic encephalopathy; intermittent claudication.
- Ruptured plaque can embolize atherosclerotic debris
- - Distal vessel obstruction and acute thrombosis
Atrophy of the media and loss of elastic tissue leads to weakness, dilatation rupture, thrombosis.
Influences extrinsic to plaques
- Adrenergic stimulation can increase BP and vasoconstriction, increasing stress on a plaque.
- - Waking and rising can cause blood pressure spikes and heightened platelet reactivity - Circadian periodicity of MI.
- – Intense emotional stress can contribute to plaque disruption - sudden death increases during disasters.
- - Compromises lumen size.
- - Potentiates plaque disruption by increasing local mechanical forces.
- - Vasoconstriction is stimulated by :
- •Circulating adrenergic agonists
- •Platelet contents released
- •Endothelial cell dysfunction - Impaired secretion of endothelial cell relaxing factors
- •? Inflammatory cells mediators
Ischemic Heart Disease
- Imbalance between the supply and demand for oxygenated blood.
- Aggravated by increased in cardiac energy demand.
- Coronary atherosclerotic lesions >90%.
Ischemic Heart Disease -Clinical syndromes
- Myocardial infarction
- Angina pectoris
- Chronic IHD with heart failure.
- Sudden Cardiac Death.
Pathogenesis of Myocardial infarction
- Chronic Atherosclerosis
- > 70% occlusion -> Symptomatic ischemia precipitated by exercise.
- 90% occlusion -> Inadequate perfusion at rest.
- Progressive ischemia -> protective collateral vessels
- Locations of clinically significant plaques:
- •First several centimeters of the LAD and LCX (left circumflex)
- •Entire RCA.
- •Major secondary epicardial branches.
- Progressive atherosclerotic narrowing -> Acute plaque change, Thrombosis, Vasospasm -> Insufficient coronary perfusion
Acute coronary syndrome
- Stable plaque abruptly converts to unstable atherothrombotic lesion.
- •Rupture, erosion, ulceration, fissuring, hemorrhage.
- •Superimposed thrombus occludes the affected artery.
- •Often associated with plaque inflammation.
Coronary Arterial Occlusion
- Sudden change in an atheromatous plaque.
- Platelets adhere to subendothelial collagen and necrotic plaque.
- - Activate and release granules.
- - Aggregate to form microthrombi.
- - Vasospasm stimulated by released platelets mediators.
- Tissue factors activate coagulation pathway, adding to thrombus.
- Thrombus evolves to complete occlusion within minutes.
- Some occlusions resolve due to fibrinolysis, or relaxation of spasm.
- - 4 hours of onset of MI - 90% thrombosed
- - 12 to 24 hours after onset - 60% thrombosed
MI in Absence of Coronary Atherosclerosis
- Vasospasm with or without coronary atherosclerosis.
- - Platelet aggregation (vasoconstrictor release)
- - Cocaine abuse (granule release -> vasoconstriction)
- Emboli from the left atrium
- - Atrial fibrillation
- - Mural thrombus
- - Vegetations of infective endocarditis
- - Prosthetic material
- Emboli from the right atrium
- - Paradoxical emboli via patent foramen ovale.
- Disorders of small vessels (intramural) -Vasculitis.
- Hematologic abnormalities - Sickle cell; amyloid deposition; apple-green stain.
- Lowered systemic blood pressure (shock).
- Inadequate myocardial “protection” during cardiac surgery.
Sequential Progression of Coronary Artery Lesions
- Normal -> atherosclerosis -> fixed coronary obstruction (FCO, typical angina) -> severe fixed coronary obstruction (SFCO, chronic ischemic heart disease)
- FCO -> platelet aggregate -> plaque disruption (PD)
- PD -> healing -> SFCO
- PD -> thrombus -> mural thrombus variable obstruction (Unstable angina, subendocardial MI, sudden death)
- PD -> thrombus -> occlusive thrombus (transmural MI, sudden death)
- Compromise of myocardial blood supply -> myocardial Ischemia, dysfunction, necrosis.
- The early biochemical consequences:
- - Cessation of aerobic metabolism within seconds leads to:
- •Inadequate production of ATP
- •Accumulation of metabolites - lactic acid
- - Myocardial function is highly oxygen dependent.
- •Loss of contractility within 60 seconds, which can precipitate acute heart failure long before myocardial cell death (irreversible at >30min).
- Within minutes of the onset of ischemia:
- •Myofibrillar relaxation
- •Glycogen depletion
- •Cell and mitochondrial swelling
- •Potentially reversible
- Severe ischemia >20-30min -> irreversible damage
- •Necrosis of cardiac myocytes.
- - Disruption of sarcolemmal membrane.
- - Intracellular macromolecules leak out of cells.
Progression of Myocardial Necrosis - Location, size, and morphology depend on:
- Location, severity, and rate of obstruction.
- Size of perfused vascular bed
- Metabolic/oxygen needs
- Collateral blood vessels
- Coronary arterial spasm
- Other - heart rate, cardiac rhythm, oxygenation.
Progression of myocardial necrosis after coronary artery occlusion
- Irreversible injury occurs first in the subendocardial zone.
- Extended ischemia - progresses to transmural infarct.
- The coronary artery that perfuses the posterior 1/3 of the septum
- •Right coronary - Right dominant
- •Left circumflex artery - Left dominant.
areas of perfusion and resulting zones of damage in hypo-perfusion of each of the main coronary arteries.
- LCX (15-20% MI)
- -> Left ventricle lateral wall
- RCA (30-40% MI)
- -> Right ventricular free wall
- -> Posterior basal LV wall
- LAD (40-50% MI)
- -> Apex
- -> Anterior LV wall
- -> Anterior 2/3 of the septum
- Global hypotension -> circumferential subendocardial MI
- Small intramural vessel occlusions -> microinfarcts
- RCA -> Posterior 1/3 ventricular septum In Right Dominant Circulation (80%)
- LCX -> Posterior 1/3 ventricular septum In left Dominant Circulation (20%)
Microscopic changes after MI
- 4–12 hr
- - Contraction bands
- - Myocytolysis
- - Wavy fibers
- - Also early coagulative necrosis, edema, and hemorrhage.
- 12-24 hr
- - Gross: Reddish blue discoloration, stagnated blood.
- - Micro: Coagulative necrosis (dead cell, architecture intact, nuclei disappear); contraction bands; edema; hemorrhage; eosinophilia; pyknosis; early neutrophilic infiltrate.
- 1-3 days
- - Gross : Mottling with softening yellow-tan infarct center
- - Micro: Coagulative necrosis, loss of nuclei and
- striations; brisk interstitial neutrophilic infiltrate.
- 7-14 days
- - Gross: Maximally yellow-tan; Depressed red-tan-gray infarct borders.
- - Micro: Phagocytosis of dead cells by MPG; Fibrovascular granulation tissue at margins; Early collagen deposition.
- 2 weeks - 2 mos
- - Gross: Gray-white scar, progresses from border
- to center.
- - Micro: Increasing collagen deposition, with decreasing cellularity; collagenous scar.
- Infarct extends beyond original borders.
- Causes of Infarct extension
- •Retrograde propagation of a thrombus.
- •Proximal vasospasm.
- •Impaired contractility causes insufficient flow through stenoses.
Infarct Modification by Reperfusion
- Rescue – Goal: Restore myocardial blood flow as rapidly as possible by reperfusion.
- Within 20 minutes of the onset of ischemia may prevent necrosis.
- Gross: Reperfused infarcts - hemorrhagic due to vascular injury.
- Micro : Contraction bands; Myocytolysis.
Complications Following Acute MI
- Contractile dysfunction - Heart failure -shock
- RV infarction - Acute right-sided heart failure
- Infarct extension
- Infarct expansion – like a balloon
- Weakening of necrotic muscle allows stretching, thinning, and dilation of the infarct region.
- Papillary muscle dysfunction/rupture – Post infarct mitral regurg.
- Progressive late heart failure
- Myocardial rupture
Complications of MI -Myocardial rupture
- Necrotic myocardium – soft and weak - Usually rapidly fatal.
- - 3 to 7 days after MI ; mean 4 to 5 days.
- - Risk factors: > 60, female, hypertension.
- Ventricular free wall - hemopericardium and cardiac tamponade
- - Most common site: antero-lateral wall, midventricular level
- Rupture of the ventricular septum - acute VSD and L-R shunt
- Early: Underlying myocardial inflammation -> fibrinous pericarditis
- Late: Dressler's syndrome - Several weeks or months post-MI - autoimmune.
- Abnormal contractility and endocardial damage
- - Potential thromboembolism.
- True aneurysms bounded by scarred myocardium
- Large transmural infarcts with early expansion.
- Paradoxically bulges during systole.
- Complications - mural thrombus; arrhythmias; heart failure.
Sudden Cardiac Death
- Unexpected cardiac death without symptomatic heart disease or early after symptom onset.
- Ischemic heart disease in most cases.
- Lethal arrhythmia – Usual cause - asystole, V-fibrillation
- •Acute myocardial ischemia -> electromechanical cardiac instability of myocardium distant from the conduction system.
- •Arrythmogenic foci - often adjacent to scars of old MIs.
Heritable conditions associated with SCD
- Anatomic abnormalities
- •Congenital anomalies
- •Hypertrophic cardiomyopathy
- •Mitral valve prolapse
- Primary electrical disorders
- •Heritable arrhythmias - Channelopathies - Mutations in genes of ion channel function.
- •Marked coronary atherosclerosis -80% to 90%
- •Nonatherosclerotic origin -10% to 20%
- •Acute plaque disruption -50%
- •Acute MI - diagnostic changes 25%
- •Myocardial ischemia–induced irritability -> malignant ventricular arrhythmias.
- - Scars of previous infarcts and subendocardial myocyte vacuolization indicate severe chronic ischemia is common.
Valvular Heart Disease
- Presentations - Stenosis, insufficiency or both.
- Clinical consequences vary depending on:
- •Valve involved
- •Degree of impairment
- •Rate of development
- •Rate and quality of compensatory mechanisms
Calcific Aortic Stenosis
- Most common of all valvular abnormalities.
- • Normal valves -70-90 y/o; Bicuspid valves- 50-70 y/o
- Wear and tear degeneration causes dystrophic and passive accumulation of calcium salt hydroxyapatite.
- • Hyperlipidemia, hypertension, inflammation play a role.
- Valve injury in CAS differs from atherosclerosis
Calcific Aortic Stenosis - Morphology
- Heaped-up calcified masses on cusps prevent opening.
- Begins in the valvular fibrosa, near the margins of attachment.
- Ultimately protrudes into the sinuses of Valsalva.
- Commissural fusion is not usually seen.
- Microscopic – Fibrosis; calcification; lipid deposits. Layered valve architecture (fibrosa is on the top/aortic side) is largely preserved.
- Gradual narrowing of the valve orifice - Valve area: Severe aortic stenosis - 0.5-1 cm2 (normal - 4cm2 )
- Concentric LVH due to increasing pressure gradient - Hypertrophied myocardium tends to be ischemic.
CAS - Onset of symptoms heralds decompensation and poor prognosis.
- Without valve replacement:
- • 50% with angina will die within 5 years.
- • 50% with CHF will die within 2 years.
Calcific Stenosis of Congenitally Bicuspid Aortic Valve
- Most frequent congenital cardiovascular malformation -1%
- Late complications: AS or AR; infective endocarditis; aortic dilation and/or dissection; cusp prolapse.
- Structural abnormalities of the aortic wall commonly accompany BAV.
- Mitral valve is generally normal.
Calcific Stenosis of Congenitally Bicuspid Aortic Valve
- The raphe is a major site of calcific deposits.
- Less frequently-cusps of equal size and raphe is absent.
- Acquired Bicuspid deformity (RVD) have a fused commissure.
Calcification of Mitral Annulus (skip)
- Degenerative calcific deposits in the mitral annulus.
- • Most common: women > 60, mitral valve prolapse and elevated left ventricular pressure.
- • Generally does not affect valve function.
- • Uncommonly leads to regurgitation; stenosis; arrhythmias, thromboemboli and infective endocarditis.
- Gross: 2–5 mm irregular, hard nodules behind leaflets.
Mitral Valve Prolapse - Myxomatous Degeneration of the Mitral Valve
- One or both mitral valve leaflets are floppy and prolapse into the left atrium during systole.
- 3% of adults in the United States.
- Commonly an incidental finding on physical examination, particularly young women.
- aka mid systolic click.
- 3% develop one of four serious complications:
- - Infective endocarditis.
- - Mitral insufficiency +/- chordal rupture.
- - Stroke or systemic infarct - embolism of leaflet thrombi.
- - Arrhythmias - both ventricular and atrial.
Mitral Valve Prolapse - Gross findings:
- Interchordal ballooning of the mitral leaflets - Hooding
- Leaflets - enlarged, thickened, redundant, and rubbery.
- Tendinous cords - elongated and thinned
- Annulus may be dilated.
- May involve tricuspid, aortic, or pulmonary valves
- Secondary changes (skip):
- • Fibrous thickening of the valve leaflets.
- • Linear fibrous thickening of the LV endocardial surface.
- • Thickening of the mural endocardium of the LV or LA.
- • Thrombi on the atrial surfaces.
- • Focal calcifications at base of the posterior mitral leaflet.
Myxomatous degeneration of the mitral valve - Microscopic findings:
- • Attenuation of the collagenous fibrosa layer of the valve.
- • Marked thickening of the spongiosa layer.
- • Deposition of mucoid “myxomatous” material
- • Can occur secondary to regurgitation of other etiologies.
Pathogenesis – Mitral valve prolapse
- Cause unknown in most cases.
- Associated with heritable disorders of connective tissue - Marfan Syndrome.
- • Defects in FBN-1 alter cell-matrix interactions and dysregulate TGF-β signaling.
- • Excess TGF-β can cause laxity and myxomatous change.
- • Can be prevented by inhibitors of TGF-β
- Autosomal-dominant forms of MVP have been mapped to other genetic loci.
Rheumatic fever and Rheumatic heart disease
- Rheumatic fever - acute, immunologically mediated, multisystem inflammatory disease that occurs a few weeks post group A streptococcal pharyngitis.
- • RF rarely follows streptococci infections at other sites.
- • Acute rheumatic carditis is common during the active phase of RF and may progress to chronic rheumatic heart disease (RHD), and deforming fibrotic valvular disease - the only cause of mitral stenosis.
Rhumatic Heart Disease - Clinical findings
- Migratory polyarthritis
- Subcutaneous nodule
- Erythema marginatum
- Sydenham chorea
Acute Rheumatic Carditis - Morphology
- Inflammation and Aschoff bodies - any layer of the heart.
- Pericarditis, myocarditis, or endocarditis - PANCARDITIS
- granuloma lesions
- Anitschkow (catepillar) cells (Collections of the histiocyte variants) with wavy ribbon-like chromatin; lymphocytes, plasma cells and MPGs.
Acute Rhumatic Fever - Verrucae
- Small (1-2mm) vegetations overly necrotic foci along lines of closure.
- Fibrinoid necrosis within the cusps or along chordae.
Chronic Rhumatic Heart Disease
- Mitral valve - Virtually always involved.
- • Alone 65% to 70%; With aortic valve 25%.
- • Pulmonary valve - rare
Chronic Rhumatic Heart Disease - Morphology
- Gross Findings:
- - Leaflet thickening; Commissural fusion.
- - Shortening, thickening and fusion of chorde.
- - Mitral leaflets
- • Organization of acute inflammation.
- • Diffuse fibrosis and neovascularization.
- • Obliteration of leaflet architecture.
- Diffuse fibrous thickening and distortion of valve leaflets.
- Fibrous bridging of valvular commissures with calcification.
- Fish mouth or buttonhole stenoses.
- Left atrium progressively dilates.
- May harbor mural thrombi in appendage or on the wall which can then embolize.
- Long-standing pulmonary congestion leads to:
- • Pulmonary hypertensive changes.
- • RV hypertrophy.
Rheumatic Aortic Stenosis
- Cusps thickened and distorted.
- Commissures fused.
- Less than 10% of cases of acquired aortic stenosis.
- Organisms colonize or invade heart valves or endocardium.
- • Vegetations of thrombotic debris and organisms often with destruction of the underlying cardiac tissues.
- • Bacterial infections >> Fungi and other microorganism classes
- • The aorta, aneurysm sacs, other blood vessels, and prosthetic devices can also become infected.
Infective Endocarditis - Pathogenesis
- Predisposing factors: Cardiac and vascular abnormalities
- • Mitral valve prolapse
- • Calcific valvular stenosis
- • Bicuspid AV
- • Artificial valves
- • Congenital defects
- • Rheumatic HD
- Risk can be lowered with antibiotic prophylaxis.
- Source of the organism:
- • Infection elsewhere
- • Dental or surgical procedure
- • Contaminated needle (IVD)
- • Trivial breaks in the epithelial barriers of gut, oral cavity, or skin.
Acute Bacterial Endocarditis
- • Rapildy progressive.
- • Highly destructive.
- • Highly virulent organisms - Staph Aureus (10-20% of cases overall)
- • Typically infects previously normal heart or deformed valves, IV drug abuser
Subacute Bacterial Endocarditis
- • More insidious protracted course.
- • Less destructive to underlying valves.
- • Less virulent organisms – Strep Viridans (50% to 60% of all cases)
- • Infects deformed valves.
Infective Endocarditis – Other causative organisms
- Enterococci and HACEK group (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella)
- Prosthetic valve endocarditis - coagulase-negative staphylococci
- Gram-negative bacilli and fungi.
- Culture-negative endocarditis -10% to 15% of all cases, still infective
Morphology - Infective Endocarditis
- Gross: Friable, bulky destructive vegetations on the heart valves; single or multiple; one or more valves.
- • sub acute vegetations - less valve destruction than acute.
- Microscopic findings:
- - Vegetations - fibrin, inflammatory cells, and organisms. Underlying tissues show granulation tissue, fibrosis, calcification, and chronic
- - Emboli containing bacteria can cause abscesses at sites where the emboli lodge -> Septic infarcts or mycotic aneurysms
Nonbacterial Thrombotic Endocarditis / Marantic endocarditis - Predisposing conditions:
- • Debilitated patients; cancer or sepsis - marantic endocarditis.
- • Systemic hypercoagulable state.
- • Association with mucinous adenocarcinomas - Procoagulant effects
- • Trousseau syndrome of migratory thrombophlebitis - pancreatic
- • Endocardial trauma: Indwelling catheter
- • Track along Swan-Ganz PA catheters
- - Small sterile thrombi on the leaflets of the cardiac valves.
- - 1 mm to 5 mm, single or multiple.
- - Along the line of closure of leaflets or cusps.
- Micro: Fibrin thrombi loosely attached to underlying valve.
- • Not invasive; no inflammation.
- • Local effect usually unimportant.
- • +/- Systemic emboli – Produce infarcts in the brain, heart, or elsewhere.
Endocarditis of SLE - Libman-Sacks Endocarditis
- Gross findings:
- • Mitral and tricuspid valves
- • 1–4 mm, single or multiple, pink, warty, sterile vegetations.
- • Undersurfaces of the AV valves; endocardium; chordae.
- Microcopic findings:
- • Fibrinous vegetations.
- • +/- Valvulitis with fibrinoid necrosis of the valve substance
- • +/- Hematoxylin bodies - degenerated nuclear material due to antinuclear Abs
- • Fibrosis and deformities can resemble CRHD and require surgery.
- RHD - rheumatic, at the cusps
- NBTE - nonbacterial thrombotic, sterile
- IE - infective, destructive
- LSE - SLE, undersurface
Carcinoid Heart Disease
- 50% of pts. with carcinoid syndrome.
- Elaboration of bioactive products by carcinoid tumors - Products are degraded in the liver.
- Tricuspid insufficiency +/- pulmonary valve insufficiency.
- Right sided stenosis.
- Tends to spare left heart because products are also broken down in the lung.
- Left-sided valvular disease – Right to left shunting; lung tumor; Serotonergic drugs.
Carcinoid Heart Disease – Gross findings
- Firm, plaque-like endocardial fibrous thickenings.
- Inside surfaces of the right cardiac chambers.
- Tricuspid and pulmonary valves.
- Occasionally involve IVC & PA.
Carcinoid Heart Disease – Microscopic findings
- • Plaque-like thickenings.
- • Smooth muscle cells and sparse collagen fibers.
- • Acid mucopolysaccharide-rich matrix.