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Have no cardiac reserve, so cannot compensate for strenuous physical activity because of the small LV chamber.

Restrictive Cardiomyopathy

• This is a disorder of ventricular compliance – The heart is normal in shape but too stiff

• Constrictive pericarditis is clinically similar – heart is mechanically prevented from contracting well Causes of Restrictive CM

• Things that infiltrate and stiffen the myocardium:

o Amyloidosis o Sarcoidosis o Metastatic tumor o Some storage diseases

o Endomyocardial fibrosis (a tropical disease of unknown cause)

• Things that thicken and stiffen the myocardium and endocardium:

o Endocardial fibroelastosis (in children - occurs with some types of congenital heart disease and rarely occurs alone)

o Loeffler endomyocarditis (assoc. with eosinophilia or eosinophilic leukemia) o Endomyocardial fibrosis (a tropical disease of unknown cause)

• Idiopathic restrictive CM – myocardium shows patchy or diffuse fibrosis

Note: In RCM the heart is about normal size and the myocardium is firm (“waxy” in amyloidosis).

Test q: What do amyloidosis of the myocardium, sarcoidosis of the myocardium, and endomyocardial fibrosis have in common? All may cause a restrictive pattern of cardiomyopathy. (Other choices: All may cause dilated cardiomyopathy, All may cause hypertrophic cardiomyopathy, All are due to deposits of abnormal protein within the interstitium of the myocardium, Aschoff bodies are typically seen in all of these entities.)

Test q: Restrictive cardiomyopathy w/impaired filling of the left ventricle due to a stiffened myocardium is most likely to result from which of the following? Cardiac amyloidosis. (Other choices: Dilated cardiomyopathy, Ischemic cardiomyopathy, Viral myocarditis, Marfan’s syndrome)

Test q: An 86M has had increasing dyspnea and reduced exercise tolerance for the past 7yr. On phys exam, he is afebrile and has a BP of 135/85. An irregularly irregular HR averaging 76/min is audible on auscultation of the chest. Crackles are heard at the bases of the lungs. A CXR shows mild cardiomegaly and mild pulmonary edema. Echocardiography shows slight right and left ventricular wall motion, reduced LV filling, and an ej fraction estimated to be 25%. An endomyocardial biopsy specimen shows amorphous pink-staining deposits between myocardial fibers but no inflammation and no necrosis. Which of the following is the most likely diagnosis? Cardiac amyloidosis. (Other choices: Rheumatic heart disease, Constrictive pericarditis, Mitral valve prolapse, LV aneurysm)

Test q: In the ER, 45min after a motor vehicle accident, a 30M who initially seemed oriented and alert becomes obtunded and hypotensive. A CXR shows an enlarged cardiac silhouette and ultrasound exam shows a large amt of fluid in the pericardial space. A pericardiocentesis is performed and 400mL of bloody fluid is withdrawn and the patient’s condition improves. The patient’s hypotension can be explained by: Impairment of cardiac filling.

(Other choices: Inflammation of the pericardium, Necrosis of myocardium due to blunt trauma to the chest, Blockage of blood flow through – or increased resistance in – the ascending aortic arch, A cardiac arrhythmia)

Cardiac Transplantation

• ~2500/year worldwide; ~5 in 2009 at Riley

• Acute cellular rejection is a form of lymphocytic myocarditis – controllable with drugs

• Transplant arteriopathy is a long term complication (aka graft vascular disease, graft arteriosclerosis) – years to a decade or more – may cause sudden death

Note: Acute cellular rejection is cell mediated and is controllable by drugs such as cyclosporine. Transplant vasculopathy on the other hand, may be mediated more by humoral means, and as yet is not controllable by drugs.

Test q: A 70M who has a cardiac transplant 4 years ago has a sudden decline in cardiac output and acute cellular rejection is suspected. What findings on an endomyocardial biopsy would confirm this impression? A myocardial lymphocytic infiltrate. (Other choices: Obliteration of the small blood vessels in the myocardium, Presence of Congo red stain-positive eosinophilic material in the myocardium, The presence of neutrophils in the endocardium) REPEATED x2

Congenital Heart Disease (CHD)

• Def: Abnormality of heart or great vessels present at birth (may be discovered as an adult)

• Usually refers to structural abnormalities such as abnormal chamber and vessel relationships, abnormal connections (holes), obstructions, absence or maldevelopment of structures, and other anatomic abnormalities

• Usually does not include congenital tumors, infections, cardiomyopathies

• Ranges from trivial (bicuspid aortic valve, persistent left superior vena cava) to lethal (absent left ventricle)

• If severe, causes retarded development, failure to thrive, increased susceptibility to infectious diseases in childhood, and rarely sudden cardiac death

• Increased risk for endocarditis (generally true for any structural abnormality, congenital or acquired; i.e. prosthetic valve)

• Increased risk during pregnancy for women with CHD

• Hyperviscosity due to polycythemia

• Nearly twice as many children die from CHD in the U.S. as from all forms of childhood cancer combined (Am.

Heart Association, 2005)

Causes of CHD

• Usually unknown - probably multifactorial (may see discordance of CHD in identical twins!)

• Around 5% chromosomal (Trisomies, Turner’s – coarctation of the aorta)

• Some (? 3%) associated with non-chromosomal single gene defects (Noonan’s, DiGeorge, numerous others)

o DiGeorge – absence of thymus/parathyroid glands – see conotruncal malformations (tetralogy of Fallot, interrupted aortic arch, VSD, persistent truncus arteriosus))

• May be seen in many malformation associations (VATER, polysplenia)

o Also, sometimes asplenia

o VATER = vertebral anomolies, anal atresia, tracheoesophageal fistula, esophageal atresia, radial/renal abnormalities, cardiovascular anomalies

• Rare - infections (rubella)

o Rubella – CHD, cataracts, deafness Major CHD Defects Can Be Lumped into 3 Categories

• Cyanotic - blood from the right side of the heart (deoxygenated blood) enters the left side (right to left shunt)

• Noncyanotic - blood from the left side of the heart enters the right side (left to right shunt)

• “Other” (i.e. no shunts, example - obstructions) Right to Left Shunts

• Cause cyanosis from early infancy

• May be complicated by paradoxical emboli

Left to Right Shunts

• No (initial) cyanosis

• Causes pressure (or volume) overload of the pulmonary circulation

• Eventually can reverse shunt direction and become cyanotic

Test q: A 20F w/congenital heart disease develops pulmonary hypertension. The development of pulmonary hypertension is most likely a complication of: A congenital heart defect w/a left-to-right shunt. (Other choices: A bicuspid aortic valve, A congenital heart defect w/a right-to-left shunt, Tricuspid atresia, Transposition of the great vessels)

Test q: The development of irreversible pulmonary hypertension is a serious complication of: A congenital heart defect w/a left-to-right shunt.

(Other choices: A congenital heart defect with a right-to-left shunt, All types of cyanotic congenital heart disease, Tetralogy of Fallot, Pulm hypertension does not occur as a complication of congenital heart disease.)

Test q: Congenital heart defects that result in the shunting of left-sided (oxygenated systemic) blood to the right (pulmonary circulation): May cause permanent injury to the pulmonary vasculature after a period of time. (Other choices: Cause cyanosis from birth, Must be surgically corrected in all cases immediately after birth, Usually involve lesions that start w/a “T”, May be alleviated by surgical placement of shunt conduit between the aorta and the pulmonic trunk to relieve high pulmonic pressures.)

Eisenmenger’s Syndrome

• Is a switch from noncyanotic to cyanotic CHD due to reversal of shunt flow

• Due to right ventricular hypertrophy and pulmonary vascular changes after prolonged pulmonary HTN

• Too late to surgically repair since pulmonary vascular changes are irreversible

• Not the same as Eisenmenger’s complex

Test q: Eisenmenger’s syndrome is best described as congenital heart disease with which of the following? A switch from noncyanotic disease to cyanotic disease. (Other choices: Electrical conduction abnormalities resulting in arrhythmia, An associated patent ductus arteriosis, A switch from cyanotic disease to noncyanotic disease)

CHD with Right to Left Shunt (Cyanotic)

• Tricuspid Atresia: Tricuspid annulus fails to canalize – no patency of tricuspid valve. Goes along w/obligatory ASD – mixing of RL blood.

• TAPVR (TAPVC): Totally anomolous pulmonary venous return – instead of going to LA, goes somewhere to the systemic venous system

• TOGV: Transposition of great vessels – aortic and pulmonic trunk reversed

• Truncus Arteriosus: Single aortic trunk – allows mixing of R & L blood

• Tetralogy of Fallot (if sufficient pulmonary outflow restriction)

• Hypoplastic left heart syndrome (probably should be considered as cyanotic): LV doesn’t develop – have single ventricle heart, R&L sides must mix

• Note: All the cyanotic types start with a T except the last one.

Test q: A newborn infant with congenital heart disease is cyanotic, even with supplementary oxygen. The category of his heart disease is most likely: A shunt defect with right-to-left flow. (Other choices: A shunt defect with left-to-right flow, An obstructive defect such as congenital aortic stenosis, A non-obstructive non-shunt defect such as an aberrant course of a coronary artery, A large VSD.) REPEATED x2

Test q: The differential diagnosis for a cyanotic newborn w/a suspected cardiovascular abnormality would include all of the following except:

Ventricular septal defect. (Other choices: Tricuspid atresia, Transposition of the great vessels, Truncus arteriosus)

CHD with Left to Right Shunt (Noncyanotic)

• ASD (increased pulmonary blood volume more than pressure)

• VSD

• AV septal Defect (AV canal) – seen in Down syndrome

• PDA

• Note: All the noncyanotic types have a D.

Test q: Which of the following congenital cardiac abnormalities is typically noncyanotic? Atrial septal defect. (Other choices: Transposition of the great vessels, Tetralogy of Fallot, Truncus arteriosus)

Test q: The differential diagnosis for a non-cyanotic newborn w/a suspected congenital cardiovascular abnormality would include all of the following except: Tetralogy of Fallot. (Other choices: Atrial septal defect, Patent ductus arteriosus, Ventricular septal defect) REPEATED x2

Test q: Based on the gross photo, the most likely abnormality in this autopsy heart from a newborn is: Patent ductus arteriosus. (Other choices:

Truncus arteriosus, Hypoplastic left heart syndrome, Tetralogy of Fallot.) Could not find this picture online – it is 2007 exam 2, #31.

Atrial Septal Defect (ASD)

• 90% are “secundum” (at foramen ovale) - the rest are rare

• Not the same as patent FO (present in up to 1/3 of normals)

• FO – 5^th valve of the heart. In the fetus, allows passage of blood through the atrial septum into the left side of the heart so the left heart can develop. This rich blood is preferentially pumped up to the head/brain so it can develop. After clipping of umbilical cord, don’t need FO anymore. Lung vascular beds open up, and pressure on the left becomes greater  flap valve closes. Eventually, in most of us it fuses and becomes continuous septum. In 1/3 of people, is patent and can open up if R pressures become higher than L. Can lead to paradoxical emboli.

• Shunts left to right (noncyanotic)

• May be asymptomatic for a long time (30 yo) or a life time

• Increased lung volume of flow more than pressure

• May eventually get volume hypertrophy of right ventricle, <10% develop irreversible pulmonary HTN

o If a patient has a big ASD and a murmur, it’s probably a pulm ejection murmur – due to greatly increased flow in right heart.

• Paradoxical embolism: A type of stroke or other form of arterial thrombosis caused by embolism of a thrombus of venous origin through a lateral opening in the heart, such as a patent foramen ovale. The opening is typically an atrial septal defect.

Note: Not many examples of pure ASD in our collection

Test q: A 58F developed thromboses of the large veins of the legs during a long airline flight. During treatment of the deep venous thrombosis, the patient suffered a cerebral infarct (stroke). A possible cause of this “paradoxical embolization” is: An atrial septal defect. (Other choices: There is an undiagnosed congenital VSD w/a left-to-right shunt, The blood clot traveled from the deep veins of the legs through the lungs to the brain, Coarctation of the aorta.)

Figures: Atrial Septal Defects: Secundum (1), Primum (2), Sinus Venosus (3),

Coronary sinus (4).

Secundum = most common ASD, usually arises from an

enlarged FO or inadequate growth of the septum secundum.

Primum = AV septal defect.

AV septal defect (aka endocardial cushion defect) – involves both atria and both ventricles of the heart, creating scooped out defect in the middle of the heart  have elements of both atrial and ventricular septal defects. Complete atrioventricular septal defect = single chamber heart, single AV valve separating the atrium from the ventricle. Small muscular part of IV septum remains. Associated w/Down syndrome.

Ventricular Septal Defect (VSD)

• Most common cardiac anomaly

• Frequently associated with other cardiac defects - about 30% isolated

• Shunts left to right (noncyanotic) initially

• About 90% involve membranous septum, others in muscular septum (looks like Swiss cheese) or below pulmonic valve

o Membranous septum – the portion just subjacent to the aortic valve annulus (the rest of the septum is muscular). Smaller defects, especially those in the muscular septum, tend to close on their own.

• Small defects - well tolerated, may close spontaneously

• Large defects - usually don’t close, and over time  Eisenmenger’s o Chronic changes occur in the vasculature of the lungs, mainly in

small muscular pulmonary arterioles (due to long-standing HT, they contract to try to compensate). Become hypertrophic, media thickens, and eventually, intimal fibrosis can occur. Arteries in the lung can become elongated and tortuous (irreversible, even if VSD fixed). Can become cyanotic CHD – pulm pressures can get so high that the shunt reverses and goes RL through VSD.

• Large defects - may have pulmonary hypertension and right ventricular hypertrophy even at birth

• Large subaortic defects – may cause prolapse and insufficiency of aortic valve

Test q: On phys exam of a non-cyanotic newborn, a murmur is detected. An echocardiogram showed a large membranous VSD (“large” meaning too large to close on its own). Surgical closure of the defect is planned when the infant is about a year old. This procedure: Is indicated before

hypertensive pulmonary vascular disease becomes irreversible. (Other choices: Should be done immediately after birth, Is elective since the condition may be handled appropriately be medical treatment, Is technically impossible, May be postponed until middle age – most patients w/this condition would not become symptomatic before that time.) REPEATED x2

Tetralogy of Fallot (TOF) Four Cardinal Features 1. RVOT obstruction (subpulmonic or valvular): Aorta

shifted to the right, overrides VSD in subaortic area 2. VSD

In document DESARROLLO.” COMUNICACIÓN EDUCACIÓNPARA “PROCESOSY (página 48-54)