Pathology Circulatie

7/30/2019 Pathology Circulatie

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Intimal thickening: vascular injury stimulates SMC growth and associated matrixsynthesis. Following endothelial injury SMC precursor cells migrate into the intima,proliferate and synthesize ECM. Intimal thickening is essentially the stereotyped responseof the vessel wall to any insult. With time and restoration and/or normalization of theendothelial layer, the intimal SMCs can return to non-proliferative state. However, by that

point , the stereotyped healing response has already resulted in intimal thickening thatmay be permanent.

Arteriosclerosis.Literally means hardening of the arteries. There are three patterns recognized:1 Arteriolosclerosis, affects small arteries and arterioles. Hyaline and hyperplastic, areboth associated with vessel wall thickening and luminal narrowing. Most often associatedwith hypertension and/or DM.2. Monckeberg medial calcific sclerosis, characterized by calcific deposits in musculararteries, typically in persons older than 50.3. Artherosclerosis.

Artherosclerosis.

Characterized by intimal lesions calledatheromas, that protruded into vascularlumina. An ahteromatous plaque consits of araised lesion with a soft, yellow, grumous coreof lipid covered by a firm, fibrous cap. Itweakens the underlying media and canthemselves rupture.

Pathogenesis.1. Endothelial injury; the cornerstone of theresponse-to-injury hypothesis. Endothelial loss dueto any kind of injury results in intimal thickening inthe presence of high-lipid diets, typical atheromasensue.

- Hemodynamic disturbance: plaques tend to occurat ostia of exiting vessels, branch points, and alongthe posterior wall of the abdominal aorta, wherethere are disturbed flow patterns.- Lipids: Are typically transported in the bloodstream bound to specific apoporteins. Commonlipoproteins abnormalities int he general populationinclude (1) increased LDL levels, (2) decreased HDL,and (3) increased levels of abnormal Lp(a). Chronichyperlipidemia can directly impair EC function byincreasing local production of reactive oxygenspecies. Oxygen free radicals accelerate nitric oxidedecay, damping its vasodilater activity and thereby

increasing local shear stress. Lipoproteinsaccumulate within the intima. These lipids are

Risk factors for Atherosclerosis.Major risks Lesser, uncertain , or

non quantitated risksNonmodifiable- Increasing age- Male gender- Family history- Geneticabnormalities

- Obesity- Physical activity- Stress (type Apersonality)- Postmenopausalestrogen deficiency- High carbohydrateintake- Lipoprotein (a)

Potentiallycontrollable- Hyperlipidemia- Hypertension- Cigarette smoking- Diabetes- C-reactive protein


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oxidized through the action of oxygen free radicals locally generated by macrophages orECs. Oxidized LDL is ingested by macrophages through a scavenger receptor, resulting infoam-cell formation. In addition, oxidized LDL stimulated the release of growth factors,cytokines, and chemokines by ECs and macrophages that increase monocyte recruitmentinto lesions.- Inflammation: monocytes transform into macrophages and engulf ox-LDL. This is

theoretically protective, cells remove potentially harmful lipid. Over time, progressiveaccumulation drives lesion progression. Macrophage activation results in cytokineproduction that further increases leukocyte adhesion. T-lymphocytes recruited to theintima interact with macrophages and can generate a chronic immune inflammatorystate. As a consequence activated leukocytes and vascular wall cells release growthfactors that promote SMC proliferation and ECM synthesis.2. Smooth muscle proliferation.Intimal SMC prolfieration and ECM deposition convert a fatty streak into a matureatheroma.


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Aneurysms and dissections.- Aneurysm: localized abnormal dilation of a blood vessel or the heart. When it involves all

three layers of the arterial walls -> true. Atherosclerotic, syphilitic, and congenitalaneurysms are of this type.

* Saccular aneurysms: essentially spherical outpouchings; they vary from 5 to 20cm in diameter

and often contain trombi.* Fusiform aneurysms: involve diffuse, circumferential dilation of a long vascular

segment;vary in diameter (


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- >6cm : 25% per year.Operative mortality for unruptured aneurysms is approximately 5%, emergency surgeryafter rupture carries a mortality rate of more than 50%.

Aortic dissection.A catastrophic event whereby blood splays apart the laminar planes of the media to form

a blood-filled channel within the aortic wall. This channel often ruptures through theadventitia and into various spaces, where it causes either massive hemorrhage or cardiactamponade. Aortic dissection occur principally in two groups: 1. Men aged 40-60 years,with antecedent hypertension and 2. Younger patients with systemic or focalizedabnormalities of connective tissue affecting the aorta.

Hypertension is the major risk. Dissection occurs in thesetting of rather trivial medial degeneration, andconversely marked degenerative changes. A considerablysmall number of dissections is related to inherited oracquired connective tissue disorders causing abnormalvascular ECM. The trigger for the intimal tear and initialintramural aortic haemorrhage is not known in most cases.

Type a lesions: proximal lesions involving either theascending aorta only or both the ascending anddescending aorta.Type b lesions: distal lesions not involving the ascending part and usually beginning distalto subclavian artery.

There is sudden onset of exruciating pain, usually beginning in the anterior chest,radiating to the back between the scapulae.

Vasculitis.Inflammation of vessel walls. Dpeending on the vascular bed affected manifestations canbe protean. Most vasculitides can affect all smal vessels from arterioles to venules.

Characteristics of selected immune-mediated vasculitides.

Vasculitis type Examples DescriptionLarge-Vesselvasculitis(Aorta and largebranches toextremities, headand neck)

Giant-cell (temperal)arteritis.

Takayasu arteritis

- Granulomatous inflammation;frequently involves temperal artery.Diagnosis depends on biopsy andhistologic confirmation. Treatmentwith corticosteroids is generallyeffective.- Granulomatous inflammation, oculardisturbances and marked weakening

of the pulses (pulseless disease).Transmural fibrous thickening of theaorta.

Medium-Vesselvasculitis(Main visceralarteries and theirbranches)

Polyarteritis nodosa

Kawasaki disease

- Necrotizing inflammation typicallyinvolving renal arteries but sparingpulmonary vessels.- Arteritis with mucocutaneous lymphnode syndrome, coronary arteries canbe involves with aneurysm formationand thrombosis

Small-vesselvasculitis( Arterioles,

venules, capillaries)

Wegener granulomatosis

Churg-Strauss syndrome

- Granulomatous inflammationinvolving the respiratory tract andnecrotizing vasculitis affecting small

vessels. Associated c-ANCAs- Eosinophil-rich and granulomatous


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inflammation involving the respiratorytract and necrotizing vasculitisaffecting small vessels. Associatedwith p-ANCAs

Veins and lymphatics.

Varicose veins.Are abnormally dilated, tortuous veins produced by prolonged increase in intraluminalpressure and loss of vessel wall support. When legs are dependent for long periods,venous pressure in these sites can be markedly elevated and can lead to venous stasisand pedal edema. Obesity increases the risk. Varicose dilation leads to stasis, congestion,edema , pain and thrombosis.

Thrombophlebitis and Phlebothrombosis: deep leg veins account for more than 90% ofcases of thrombophlebitis and Phlebothrombosis; the two terms are largelyinterchangeable designations for venous thrombosis and inflammation. Thrombi in thelegs tend to produces few, if any, reliable signs or symptoms. Local manifestations,

including distal edema, cyanosis, superficial vein dilation, heat, tenderness, redness,swelling and pain. Pulmonary embolism is a common and serious clinical complication ofDVT.

Superior and inferior Vena Caval Syndromes: usually causes by neoplasms that compressor invade the superior vena cava. The resulting obstruction produces a characteristicclinical complex including marked dilation of the veins of the head, neck and arms withcyanosis. Inferior vena caval syndrome can be caused by neoplasms that compress orinvade the i.v.c. or by a thrombus from hepatic, renal, or lower extremity veins.

Lymhangitis and lymphedema: Primary disorders of lymphatic vessels are extremelyuncommon. Lymphangitis is the acute inflammaition elicited when bacterial infectionsspread into and through the lymphatics; most common agents are group A betahemolytic streptococci. The affected lymphatics are dilated and filled with an exudate ofneutrophils and monocytes. Clinically recognized by red , painful subcutaneous streaks,with painful enlargement of the draining lymph nodes.- Peau dorange: Lymphedema increases the hydrostatic pressure in the lymphaticsbehind the obstruction and causes increased interstitial fluid. Increased deposition ofinterstitial connective tissue, with tissue expansion, brawny induration appearance of theoverlying skin, and eventually ulcers due to inadequate tissue perfusion.

Tumors.- Benign tumors usually produce obvious vascular channels filled with blood cells , linedby a monolayer of normal Ecs, without atypia.-Malignant tumors are more solidly cellular with cytologic anaplasia, they usually do not

form well-organized vessels.

Benign tumors and tumor-like conditions.

Hemangioma: very common tumors characterized by increased number of normal orabnormal vessels filled with blood. These lesions constitute 7% of all benign tumors ofinfancy in childhood- Capillary hemangioma: most common variant, occur in the skin, subcuteneous tissuesand mucous membranes of the oral cavity.- Cavernous hemangioma: characterized by large, dilated vascular channels. Are less wellcircumscribed and more frequently involve deep structures. May be locally destructiveand show no spontaneous tendency to regress, some may require surgery.- Pyogenic granuloma: rapidly growing penduncular red nodule on the skin, gingival, or

oral mucosa; bleeds easily and is often ulcerated. Proliferating capillaries are oftenaccompanied by extensive edema and an acute and chronic inflammatory infiltrate.These lesions can spontaneously regress or undergo fibrosis; recurrence is rare


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Lymphangioma: the benign lymphatic analogue of hemangiomas.- Simple (capillary) lymphangioma: are composed of small lymphatic channels. They areslightly elevated. Histologically they show networks of endothelium-lined spaces than canbe distinguished from capillary channels only by the absence of blood cells.- Cavernous Lymphangioma (cystic hygroma): typically found in the neck or axilla of

children. Lesions can occasionally be enormous and may fill the axilla or produce grossdeformities about the neck. The tumor margins are not discrete and the lesions are notencapsulated, making resection difficult.

Glomus tumor (glomangioma): biologically benign but often exquisitely painful tumorsarising from SMCs of the glomus body. They are most commonly found in the distalportion of the digits, especially under the fingernails. Excision is curative.

Ch.11 The heart.

1.1 Heart failure.Most heart failure is the consequence of systolic dysfunction, the progressivedeterioration of myocardial contractile function; this is most commonly due to ischemicheart disease or hypertension. Patients with diastolic failure are generally more older andmore likely to be female with hypertension or diabetes. In heart failure, the heart isunable to pump blood at a rate that meets the requirements of the metabolizing tissues,or can only do so only with filling pressures that are higher than normal.- Forward failure: inadequate cardiac output, almost always accompanied by increasedcongestion of venous circulation-> backward failure, because the failing ventricle isunable to eject the venous blood delivered to it. This results in an increased end diastolicventricular volume, leading to increased en diastolic pressures and, finally, elevatedvenous pressures.

Cardiovascular system can adapt:- Activation of neurohumoral systems, 1. Release of norepiniephrine (increases heart

rate), 2. Activation of the renin-angiotensinaldosterone system, 3. Release of atrialnatriuretic peptide (ANP) (polypeptide hormone secreted by the atria and causesvasodilation, naturiuresis, and diuresis.- Frank-starling mechanism: end-diastolic pressure increases, causing individual cardiacmuscle fibres to stretch; increase the volume of cardiac chamber; lengthened fibersinitially contract more forcibly and thereby increasing cardiac output.- Myocardial structural changes, including augmented muscle mass (hypertrophy): adultcardiac myocytes cannot proliferate, adaptation to a chronically increased workloadinvolves hypertrophy. It is characterized by increasing diameter of individual musclefibers (concentric hypertrophy), in which the thickness of the ventricular wall increaseswithout an increase in the size of the chamber. In volume overload states the length ofindividual muscle fibers that increases (eccentric hypertrophy), increase the heart size aswell as wall thickness.

1.2. Left-sided heart failure.Clinical effects result from progressive damming of blood within the pulmonary circulationand the consequences of diminished peripheral blood pressure and flow. Clinical features:

- Dyspnea- With further cardiac impairment -> orthopnea, occurs because of increased venousreturn from the lower extremities- Enlarged heart (cardiomegaly)- A third heart sound (S3)- Tachycardie

1.3. Right-sided heart failure

Usually the consequence of left-sided heart failure; any pressure increase it thepulmonary circulation inevitably produces and increased burden on the right side of the


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heart. Isolated right-sided occurs in patients with intrinsic disease of the lung and/orpulmonary vasculature. It can also occur in patients with pulmonic or tricuspid valvedisease. Clinical features:- Pure right sides heart failure causes very few respiratory symptoms;- There is systemic and portal venous congestion- Hepatic and splenic enlargement

- Peripheral edema- Pleural effusion and ascites

2.1 Congenital heart disease.Most disorders arise from faulty embryogenesis during gestational weeks 3 through 8.Congenitla heart diseases can be subdivided into three major groups:- Malformations causing left-to-right shunts; A shunt is an abnormal communicationbetween chambers or blood vessels. It increases (in this case) pulmonary blood flow andthey are not assocaited with cyanosis. They expose the low pressure pulmonarycirculation to increased pressure and volume, resulting in right, ventricular hypertrophyand right-sided failure.- right-to-left shunts; causes a dusky blueness of skin (cyanosis)- obstruction; a complete obstruction is called atresia.

2.2 Left-to-right shuntsMost common type include atrial and ventricular septal defects, and patent ductusarteriosus. Cyanosis is not an early feature, it can occur later. Eisenmenger syndrome ->

once significant pulmonary hypertension develops, the structural defects of congenitalheart disease are considered irreversible.

Atrial septal defects: The ingrowth of the septum from the dorsal wall of the commonatrial chamber toward the endocardial cushion; a gap (ostium primum) initially separatesthe two. Continued growth and fusion of the septum with the endocardial cushionobliterates the ostium primum. A second opening (ostium secundum) now appears. Asthe ostium secundum enlarges, the septum secundum makes its appearance adjacent tothe septum primum -> foramen ovale, the flaps acts as a one-way valve. Three type arerecognized:- Most common (90%) is the ostium secundum ASD, when the septum secundum does notenlarge sufficiently to cover the ostium secundum;- Ostium primum ASDS (5%);

- Sinus venosus ASDS (5%), are located near the entrance of the superior vena cava.

Ventricular septal defects: septum is normally formed by the fusion of an intraventricular

musclar ridge that grows upward from the apex of the heart with a thinner membranouspartition that grows downward from the endocardial cushion. The basal (membranous)


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region is the last part to develop and is the site of approximately90% of VSDs. Most VSDs close spontaneously in childhood.

Patent ductus arteriosus: During intrauterine life, the ductusperimits blood flow from the pulmonary artery to the aorta,bypassing the unoxygenated lungs. The constriciton of the ductus

occurs in response to increased arterial oxygenation, decreasedpulmonary vascular resistance, and declining local levels ofprostaglandin E2. The ductus is functionally nonpatent with 1-2days after birth -> lig. Arteriosum. Closure is often delayed ininfants with hypoxia. Clinical features:- They are high pressure left-to-right shunts,audible as harsh machinery-like murumrs.- Large bore effects eventually lead to Eisenmengersyndrome with cyanosis and CHF.

2.3. Right-to-left shunts.Distinguished by cyanosis at or near the time ofbirth. This occurs because poorly oxygenated blood

from the right side of the heart is introduceddirectly into the arterial circulation.- Tetralogy of Fallot;- Transposition of the great vessels.Right-left-shunts permit venous emboli to bypass the lungs and directly enter thesystemic circulation -> paradoxical embolism.

Tetralogy of Fallot: 5% of all congenital cardiac malformations.1. VSD2. Obstruction to right ventricular outflow tract (subpulmonic stenosis)3. An aorta that overrides the VSD4. Right ventricular hypertrophy.Even untreated some patients can survive into adult life. Clinical features: right-to-leftshunting -> decreased pulmonary blood flow, and increased aortic volumes. If thepulmonic obstruction is mild, the condition resembles and isolated VSD. Marked stenosiscauses significant right-to-left shunting and consequent cyanosis early in life. The lungsare protected from hemodynamic overload by the pulmonic stenosis, so pulmonaryhypertension does not develop.

Transposition of the great arteries: is a discordant connection of the ventricles to theirvascular outflow. The functional outcome is separation of the systemic and pulmonarycirculations, a condition incompatible with postnatal life unless a shunt exists foradequate mixing of blood. Clinical features: early cyanosis. Infusion of prostaglandin E2can be used to maintain patency of the ductus arteriosus. Even with stable shunting ,most uncorrected TGA patients still die within first months of life. Consequently, affected

individuals usually undergo corrective surgery within week of birth.

2.4. Obstructive lesions.

Aortic coarctation: relatively common structural anomaly and is the most important formof obstructive congenital heart disease. Males are affected twice as much. Two classicforms have been described:- Hypoplasia of the aortic arch proximal to PDA- An adult form in which there is a discrete rigdelike infolding of the aorta, just oppositethe lig. Arteriosum distal to the arch vessels.Clinical features: depend almost entirely on the severity of the narrowing. Preductalcoarctation with PDA: leads to manifestation early in life. The delivery of poorlyoxygenated blood through the ductus arteriosus produces cyanosis localized to the lower

half of the body. Postductal coarctation without PDA: usually asymptomatic and thedisease may go unrecognized until well into adult life. There is upper extremityhypertension, due to poor perfusion of the kidneys, but weak pulses and lower blood


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pressure in the lower extremities.

3.1 Ischemic heart disease (IHD).Four basic clinical syndromes:1. Angina pectoris: Stable, due to vessel spam (variant angina or Prinzmetal angina) orunstable.

2. Acute myocardial infarction (MI).3. Chronic IHD -> progressive cardiac decompensation.4. Sudden cardiac death.

In most cases IHD occurs because of inadequate coronary perfusion relative tomyocardial demand. A lesion obstructing 70-75% or more of a vessel lumen generallycauses symptomatic ischemia (angina) only in the setting of increased demand. A fixed90% of stenosis can lead to inadequate coronary blood flow even at rest.

Role of acute plaque change: in most patients infarction all occur because of abruptplaque change followed by thrombosis. Rupture reflects the inability of a plaque towithstand mechanical stresses. Plaques contain a large athermatous core or those inwhich the overlying fibrous caps are thin are more likely to rupture and are therefore

denoted as vulnerable. Fibrous caps are also continuously remodelling; the balance ofcollagen synthesis and degradation determines its mechanical strength and thus plaquestability. Adrenergic stimulation can elevate physical stresses on the plaque throughsystemic hypertension or local vasospasm. CAVE! 2/3 of ruptured plaques are more prolonged ischemia, a wavefront of cell death moves through the myocardium.


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Infarct usually reaches it full size within 3-6 hours.

Changes in an infarct due to reperfusion: therapeutic goal is restoration of tissueperfusion as quickly as possible. Such reperfusion is achieved by thrombolysis, balloonangioplasty, or coronary arterial bypass graft. There is a distinct entity of reperfusioninjury that can incite greater local damage than might have otherwise occurred without

rapid restoration of blood flow. Reperfusion injury is mediated in part by oxygen freeradicals generated by the increased number of infiltrating leukocytes facilitated byreperfusion. It causes not only hemorrhage but also endothelial swelling that occludescapillaries and may prevent local blood flow (no-reflow). A reperfused infarct usually hashemorrhage because the vasculature injured during the period of ischemia is leaky afterflow is restored.

Complications after acute MI:- Contractile dysfunction: some degree of left ventricular failure, with hypotension,pulmonary vascular congestion, and fluid transudation into the pulmonary interstitialalveolar spaces.- Arrhythmias: include sinu bradycardia, heat block, tachycardia, ventricular prematurecontraction or ventricular tachycardia, and ventricular fibrillation.

- Myocardial rupture.- Pericarditis: develops within 2-3 days of a transmural MI.- Infarct expansion.- Mural thrombus- Ventricular aneurysm: late complication.- Progressive late heat failure.

4.1 Hypertensive heart disease.Cardiac myocytes do not have the capacity to divide. Hyperplasia cannot occur inresponse to exogenous stresses. Instead increased work induces an increased myocytemass and heart size (hypertrophy). Heart weights usually range from 350 to 600 gm.Pressure-overload ventricles (e.g. in hypertension or aortic valve stenosis) developconcentric hypertrophy, with an increased wall thickness. In contrast, volume overload(e.g. aortic valve insufficiency) by hypertrophy associated with ventricular dilation.

4.2. Systemic hypertensive heart disease.Is diagnosed when 1. Left ventricular hypertrophy in the absence of other causalcardiovascular pathology and 2. A history or pathologic evidence of hypertension. Clinicalfeatures: it may by asymptomatic and suspected only by ECG indications of leftventricular hypertrophy. Increased cardiac mass is an independent risk factor for suddencardiac death.

4.3. Pulmonary hypertensive heart disease (cor pulmonale).Consists of right ventricular hypertrophy and dilation due to pulmonary hypertensioncaused by primary disorders of the lung parenchyma or pulmonary vasculature. It may be

acute (massive embolism with obstruction > 50%) or chronic, which occurs secondary toprolonged pressure overload.

5.1 Valvular heart disease.

5.2. Calcific aortic stenosis.Can be thought of as valvular counterparts of age-related arteriosclerosis. Usually theconsequence of calcification from progressive age-associated wear and tear. Inanatomically normal valves, it typically begins to manifests when patients reach their 70sor 80s. Clinical features: in severe calcific aortic stenosis, valve orifices can becompromised by as much as 70 to 80%. The resulting left ventricular outflow obstructionleads to left ventricular pressures as high as 200mmHg. Cardiac output is maintainedonly by virtue of concentric left ventricular hypertrophy. Hypertrophied myocardium

tends to be relatively ischemic -> angina can develop.

5.2. Myxomatous mitral valve.


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One or both mitral leaflets are floppy and prolapse. They balloon back into the leftatrium during systole. Occurs 7 times more often in women. The basis is unknown. Thereis almost certainly some underlying intrinsic defect of connective tissue -> a commonfeature of Marfan. Clinical features: most patients are asymptomatic. A minority ofpatients may complain of palpitations, dyspnea, or atypical chest pain. Auscultationdiscloses midsystolic clicks caused by abrupt tension on the redundant valve leaflets and

chordae tendineae as the valve attempts to close.

5.3. Rheumatic valvular disase (RHD).Rheumatic fever (FR) is an acute, immunologically mediated, inflammatory disease thatoccurs a few weeks after an episode of group A beta-hemolytic streptococcal pharyngitis.RHD is the cardiac manifestation of FR and is associated with inflammation of the valves,myocardium, or pericardium. Chronic valvular deformities are the most importantconsequences of RHD; characterized by diffuse and dense scarring of valves resulting inpermanent dysfunction. Pathogenesis: a hypersensitivity reaction induced by hostantibodies elicited by group A streptococci.

5.4. Infective endocarditis.A serious infection requiring prompt diagnosis and intervention. Characterized by

microbial invasion of heart valves or mural endocardium and results in bulky, friablevegetations composed of necrotic debris, thrombus and organisms. IE can develop onpreviously normal valves, but the presence of cardiac abnormalities predisposes to suchinfections. Fever is the most consistent sign.

5.4. Noninfected vegetations.- Nonbacterial thrombotic endocarditis: characterized by the deposition of variably sizedmasses of fibrin, platelets and other blood components on cardiac valves. Valvular lesionsare sterile and do not contain microorganisms. The condition is usually found onpreviously normal valves. Typically occurs in the setting of hypercoagulable states (e.g.sepsis with disseminated intravascular coagulation). NBTE lesions can become clinicallysignificant by embolizing to the brain, heart or other organs.- Libman-sacks Endocarditis: refers to sterile vegetations that can develop on the valvesof patients with systemic lupus erythematosus.

5.5. Carcinoid heart disease.Cardiac manifestations of a systemic syndrome that includes flushing, diarrhoea,dermatitis, and bronchoconstriction, caused by bioactive compounds released bycarcinoid tumors. The mediators in include serotonin, kalikrein, bradykinin, histamine,prostaglandins, and tachykinins.6.1 Cardiomypathies.Cardiac disease attributable to intrinsic myocardial dysfunction. Such myocardial diseasesare termed cardiomyopathies. American heart association classification divides them intotwo groups: 1. Primary includes those entities in which the heart muscle and 2.Secondary in which heart is involved as a part of a generalized multiorgan disorder. More

clinical and functional three groups:- Dilated cardiomyopathy (most common, 90% of cases)- Hypertrophic cardiomyopathy- Restrictive cardiomyopathy


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6.2. Dilated cardiomyopathy.Characterized by progressive cardiac dilation and contractile (systolic) dysfunction. 25-35% of cases have a familial basis. Other result from a variety of acquired myocardialinsults including toxic exposures, myocarditis etc. When discovered clinically , DCM isfrequently at its end stage. The causes can be divided into 4 broad categories:- Viral; coxsackie.

- Alcohol or other toxic exposure.- Genetic influences.- Peripartium cardiompyopathy occurs late in gestation or several weeks to monthspostpartum.DCM can occur at any age, including in childhood, but it most commonly occurs betweenages 20 to 50 years. Presents with slowly progressing CHF.

Arrhythmogenic right ventricular cardiomyopathy: is a unique entity with a clinicalpresentation involving right-sided heart failure and various rhythm disturbances. Rightventricular wall is severely thinned as result of myocyte replacement by massive fattyinfiltration and lesser amounts fibrosis.

6.3. Hypertrophic cardiomyopathy.

Characterized by myocardial hypertrophy, abnormal diastolic filling and ventricularoutflow obstruction. The heart is thick-walled, heavy and hypercontracting, in strikingcontrast to the flabby, poorly contractile heart in DCM. Pathogenesis: almost all cases arecaused by missense point mutations in one of several genes encoding the sarcomericproteins that form the contractile apparatus of straited muscle. Clinical features:- Massively hypertrophied left ventricle that paradoxically provides a markedly reducedstroke volume.- Impaired diastolic filling and overall smaller chamber size (direct consequence of theabove).

6.4. Restrictive cardiomyopathy.Characterized by a primary decrease in ventricular compliance, resulting in impairedventricular filling during diastole. Contractile (systolic) function of the left ventricle isusually unaffected. It can be idiopathic or associated with systemic diseases that alsohappen to affect the myocardium (e.g. radiation, fibrosis, amyloidosis). Two other formmerit brief mentioning:- Endomyocardial fibrosis;- Loeffler endomyocarditis.

6.5. Myocarditis.There is inflammation of the myocardium with resulting injury. Presence of inflammationalone is not diagnostic of myocarditis; in myocarditis the inflammatory process is thecause of myocardial injury. Pathogenesis: Coxsackieviruses A and B and otherenteroviruses probably account for most of the cases. Clinical features: Clinical spectrumis broad. The disease is asymptomatic and patients recover without sequel, or at the

other end is the precipitous onset of heart failure or arrhythmias, occasionally withsudden death.7.1 Pericardial disease.Include inflammatory conditions and effusions. Isolated pericardial disease is unusual.

7.2. Pericarditis.Primary pericarditis is uncommon; in most cases it is caused by infection. Viruses areusually responsible. In most cases pericarditis is secondary to acute MI, cardiac surgery,irradiation to the mediastinum or processes involving other thoracic structures. It cancause1. Immediate hemodynamic complications if a significant effusion is present;2. Resolve without significant sequelea, or3. Progress to a chronic fibrosing process.

It presents with atypical chest pain, not related to exertion and often worse on reclining,and a prominent friction rub. Acute pericarditis can cause cardiac tamponade.


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7.3. Pericardial effusions.There is about 30 to 50 mL of thin, clear straw-coloured fluid in the pericardial sac(normally). The major types include:- Serous: CHF, hypoalbuminemia;- Serosanguinous: blunt chest trauma, malignancy;- Chylous: mediastinal lymphatic obstruction.

The consequences depend on the ability of the parietal pericardium to stretch.

Pathology Circulatie

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