Term
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Definition
| When the heart is unable to pump blood at a rate sufficient to meet the metabolic demands of the tissues or can do so only at an elevated filling pressure |
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Term
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Definition
During the end stage of many forms of chronic heart disease. MOST OFTEN develops insidiously due to the cumulative effects of chronic work overload or ischemic heart disease
Acute hemodynamic stresses, such as fluid overload, acute valvular dysfunction, or a large MI can cause CHF to appear suddenly |
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Term
| What are the physiologic mechanisms that maintain arterial pressure and perfusion of vital organs? |
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Definition
1. Frank-Starling mechanism: increased filling volumes dilate the heart and thereby increase functional cross-bridge formation within the sarcomeres and enhance contractility
2. Myocardial adaptations: hypertrophy with or without cardiac chamber dilation
3. Activation of neurohumoral systems: norepinephrine, renin-angiotensin-aldosterone, atrial natriuretic peptide |
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Term
| What is systolic dysfunction? |
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Definition
Myocardial contractile function, may be attributable to ischemic injury, pressure or volume overload due to valvular disease or hypertension or dilated cardiomyopathy
Systolic failure: defined by insufficient cardiac output (pump failure) |
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Term
| What does heart failure most frequently result from? |
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Definition
| MYOCARDIAL CONTRACTILE FUNCTION (systolic dysfunction) |
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Term
| Pressure Overload Hypertrophy |
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Definition
In response to increases in pressure
ex. hypertension or aortic stenosis
causes a concentric increase in wall thickness
new sarcomeres are predominantly assembled in parallel to the long axes of cells expanding the cross-sectional area of myocytes
-static exercise, more likely to be associated with deleterious changes |
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Term
| Volume overload hypertrophy |
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Definition
-characterized by ventricular dilation
-new sarcomeres assembled in response to volume overload are largely positioned in SERIES with existing sarcomeres
-heart weight rather than wall thickness is the best measure because wall thickness may be increased, normal, or less than normal
- may be accompanied by increases in capillary density and decreases in resting HR and BP which are all beneficial effects |
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Term
| Tissue and Cell changes in cardiac hypertrophy |
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Definition
-Increase in myocyte size is not accompanied by a proportional increase in capillary number
-supply of oxygen and nutrients to the hypertrophied heart is more tenuous than a normal heart
-oxygen consumption is elevated due to increased workload
-hypertrophy often accompanied by deposition of fibrous tissue |
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Term
| Why is a hypertrophied heart vulnerable to decompensation? |
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Definition
| -associated with heightened metabolic demands due to increases in wall tension, heart rate, ad contractility all of which increase cardiac oxygen consumption |
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Term
| What is Left-Sided heart failure most often caused by? |
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Definition
1. ischemic heart disease
2. hypertension
3. aortic and mitral valvular diseases
4. myocardial diseases
Morphologic and clinical effects result from congestion of the pulmonary circulation, stasis of blood in the left-sided chambers, and hypoperfusion of tissues leading to organ dysfunction |
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Term
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Definition
| Characteristic lines noted on chest roentgenogram produced by the perivascular and interstitial edema particularly in the interlobular septa |
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Term
| What are the pulmonary changes that occur in LSHF |
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Definition
1. Kerley B lines from perivascular and interstitial edema
2. progressive edematous widening of alveolar septa
3. accumulation of edema fluid in the alveolar spaces
4. Heart failure cells |
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Term
| What are Heart Failure Cells |
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Definition
hemosiderin-laden macrophages
-telltale sign of previous episodes of pulmonary edema
-some red cells extravasate into the edema fluid in alveolar spaces
-they are then phagocytosed and digested by macrophages which store Fe recovered from hemoglobin in the form of hemosiderin |
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Term
| Paroxysmal Nocturnal Dyspnea |
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Definition
| form of dyspnea (breathlessness) so severe it induces a feeling of suffocation |
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Term
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Definition
"stiffening of the heart"
CO relatively preserved at rest, but the LV is abnormally stiff or otherwise restricted in its ability to relax during diastole
-most common in patients over 65 y/o
-more common in women
-Hypertension is the most common underlying etiology |
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Term
| Most common cause of RSHF? |
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Definition
LSHF
-anuy increase in pressure in the pulmonary circulation incidental to LSHF inevitably burdens the RS of the heart |
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Term
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Definition
Pure RSHF
-infrequent, usually occurs in patients with any one of a variety of disorders affecting the lungs
-common feature is pulmonary hypertension which results in hypertrophy and dilation of the right side of the heart |
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Term
| What is cor pulmonale most commonly associated with? |
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Definition
parenchymal diseases of the lung
-can also arise secondary to disorders that affect the pulmonary vasculature such as pulmonary hypertension, recurrent pulmonary thromboembolism
-OR from thins that produce hypoxia such as chronic sleep apnea, altitude sickness |
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Term
| How do the major morphologic and clinical effects of RSHF differ from LSHF? |
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Definition
| In RSHF pulmonary congestion in minimal whereas engorgement of the systemic and portal venous systems may be pronounced |
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Term
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Definition
| Congestion of the hepatic and portal vessels occurs in RSHF and is most prominent around central veins within hepatic lobules. These ventral veins show red-brown centrilobular discoloration and paler, sometimes fatty peripheral regions producing the characteristic appearance referred to as nutmeg liver |
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Term
| When does centrilobular necrosis occur? |
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Definition
| When both LSHF and RSHF are present, severe central hypoxia produces centrilobular necrosis |
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Term
| What is a hallmark of RSHF? |
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Definition
edema of the peripheral and dependent portions of the body, especially ankle and pretibial edema
-Anascara or generalized massive edema |
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Term
| When do most congenital heart disorders arise? |
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Definition
Present from birth
-most arise from faulty embryogenesis during gestational weeks 3 through 8, when major cardiovascular structures form and begin to function |
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Term
| Congenital cardiovascular defects |
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Definition
most prevalent malformations and are the most common type of heart disease among children
-incidence is higher in premature infants and stillborns |
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Term
| How are many of the genetic defects that affect heart development classified? |
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Definition
Autosomal dominant mutations
-cause partial loss of function in one or another required factor which are often transcription factors |
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Term
| What are the main known causes of congenital heart disease? |
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Definition
sporadic genetic abnormalities
-single gene mutaitons
-small ch deletions
-additions or deletions of whole ch |
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Term
| What is the most common genetic cause of congenital heart disease? |
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Definition
trisomy 21
-40% patients have one or more heart defects, most often affecting structures derived from the endocardial cushions |
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Term
| What are the 3 major categories for varied structural anomalies in congenital heart disease? |
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Definition
1. Left to right shunts
2. Right to left shunts
3. obstruction
A shunt is an abnormal communication between chambers or blood vessels |
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Term
| What are the most important causes of right to left shunts? |
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Definition
tetralogy of Fallot
transposition of the great arteries
persistent truncus arteriosus
tricuspid atresia
total anomalous pulmonary venous connection |
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Term
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Definition
emboli arising in peripheral veins that can bypass the lungs and directly enter the systemic circulation
-possible with right to left shunts |
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Term
| What does severe long-standing cyanosis cause? |
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Definition
clubbing of the tips of the fingers and toes (called hypertrophic osteoarthropathy) and polycythemia (proportion of blood volume occupied by RBCs increases)
-Hypoxia and cyanosis occur in right to left shunt because blood is not going to the lungs to get oxygenated and this gets mixed with oxygenated blood that does go to the lungs |
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Term
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Definition
late cyanotic congenital heart disease
-occurs in left to right shunts because at first, they are not associated with cyanosis, but eventually pulmonary vascular resistance approaches systemic levels thereby producing a new right to left shunt that introduces unoxygenated blood into the systemic circulation |
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Term
| When are the structural defects of congenital heart disease considered irreparable? |
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Definition
| once irreversible pulmonary hypertension develops |
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Term
| What are the most commonly encountered left to right shunts? |
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Definition
| ASDs, VSDs, patent ductus arteriosus, and atrioventricular septal defects |
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Term
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Definition
| Abnormal fixed opening in the atrial septum caused by incomplete tissue formation that allows communication of blood between the left and right atria |
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Term
| What is the most common type of ASD? |
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Definition
Secundum ASDs (90%) result from a deficient or fenestrated oval fossa near the center of the atrial septum
-usually not associated with other anomalies |
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Term
| What are the 3 types of ASDs? |
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Definition
1. Secundum (most common)
2. Primum - occur adjacent to the AV valves
3. Sinus Venosus- located near the entrance of the SVC, may be associated with anomalous pulmonary venous return to the RA |
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Term
| What is the most common form of congenital cardiac anomaly? |
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Definition
incomplete closure of the ventricular septum
VSD
allows free communication of blood btw left and right ventricles
-most are associated with other congenital cardiac anomalies
-classified according to size and location
90% involve the membranous interventricular septum |
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Term
| Which congenital heart anomaly produces a characteristic continuous "machinery-like" harsh murmur? |
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Definition
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Term
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Definition
Two most common forms
1. partial: consisting of primum ASD and a cleft anterior mitral leaflet causing mitral insufficiency
2. complete: consisting of a large combined AV septal defect and a large common AV valve - a hole in the center of the heart
-more than 1/3 of all pts with complete have down syndrome |
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Term
| What is the most common R to L shunt? |
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Definition
Tetralogy of Fallot
PROV
Pulmonary valve stenosis
RV hypertrophy
Overriding aorta
VSD |
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Term
| Transposition of the Great Arteries |
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Definition
Aorta arises from RV and pulmonary artery arise from LV
-separation of the systemic an pulmonary circulations
-incompatible with life unless a shunt exists for adequate mixing of blood |
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Term
| Persistent Truncus Arteriosus |
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Definition
Single Great Artery that receives blood from both ventricles
-failure of embryological separation of the truncus arteriosus into the aorta and pulmonary artery
-produces systemic cyanosis as well as increased pulmonary blood flow with danger of irreversible pulmonary hypertension |
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Term
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Definition
complete occlusion of the tricuspid valve orifice
-cyanosis present from birth |
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Term
Total anomalous pulmonary venous connection
TAPVC |
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Definition
pulmonary veins fail to directly join the LA
-volume and pressure hypertrophy and dilation of the right side of the heart and dilation of the pulmonary trunk |
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Term
| What are examples of obstructive congenital anomalies? |
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Definition
Coarctation of the aorta
Pulmonary stenosis and atresia
Aortic stenosis and atresia |
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Term
| What are the 2 classic forms of coarctation of the aorta? |
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Definition
Note: males affected twice as often as females although females with Turner syndrome have it more frequently
1. Infantile: tubular hypoplasia of the aortic arch PROXIMAL to a patent ductus arteriosus that is often symptomatic in early childhood
2. Adult: discrete ridgelike infolding of the aorta just opposite the closed ductus arteriosus distal to the arch vessels |
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Term
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Definition
-cusps may be hypoplastic, dysplastic, or abnormal in number
-hypoplastic left heart syndrome: PDA, obstruction of LV leading to hypoplasia of LV and ascending aorta sometiems accompanied by dense, porcelain-like left ventricular endocardial fibroelastosis
-fatal if PDA closes in frist week of life unless palliative procedure is done |
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Term
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Definition
caused by thickened ring or collar of dense endocardial fibrous tissue below the level of the cusps
-usually associated with a prominent systolic murmur and sometimes a thrill |
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Term
| Supravalvular aortic stenosis |
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Definition
inherited form of aortic dysplasia in which the ascending aortic wall is greatly thickened causing luminal constriction
-hypercalcemia, cognitive abnormalities, and hallmark facial anomalies (Williams-Beuren syndrome)
-mutations in elastin gene |
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Term
| Supravalvular aortic stenosis |
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Definition
inherited form of aortic dysplasia in which the ascending aortic wall is greatly thickened causing luminal constriction
-hypercalcemia, cognitive abnormalities, and hallmark facial anomalies (Williams-Beuren syndrome)
-mutations in elastin gene |
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