(2) Cardiovascular diseases 2 Flashcards
1
Q
Give 3 primary causes of left sided heart failure
A
- hypertension (pressure overload)
- valvular disease (pressure and/or volume overload)
- myocardial infarction (regional dysfunction with volume overload)
2
Q
Pressure and volume overload are the causes behind left sided heart failure. What are the stages leading to cardiac dysfunction?
A
Increased pressure/volume overload = increased cardiac work = wall stretch = cell stretch = hypertrophy and/or dilation
3
Q
Hypertrophy and/or dilation in left sided heart failure is characterised by what?
A
- increased heart size and mass
- increased protein synthesis
- induction of immediate-early genes
- induction of foetal gene programme
- abnormal proteins
- fibrosis
- inadequate volume
4
Q
Hypertrophy and/or dilation leads to cardiac dysfunction. What is this characterised by?
A
- heart failure (systolic/diastolic)
- arrhythmias
- neurohumoral stimulation
5
Q
What 2 main things does left sided heart failure cause?
A
- low output
- congestion
6
Q
How does low output due to left sided heart failure affect the kidneys?
A
- pre-renal azotemia
- RAAS activation
- salt and fluid retention
- natriuretic peptides
7
Q
Pre-renal azotemia may occur in left sided heart failure. What is it?
A
Abnormally high levels of nitrogen-containing compounds (such as urea, creatinine, various body waste compounds, and other nitrogen-rich compounds) in the blood.
Related to insufficient or dysfunctional filtering of blood by the kidneys
8
Q
What are natriuretic peptides?
A
Peptides which induce natriuresis (the discharge of sodium through urine).
9
Q
How does low output due to left sided heart failure affect the brain?
A
- irritability
- decreased attention
- stupor
- coma
10
Q
What is stupor?
A
A state of near-unconsciousness or insensibility
11
Q
How does congestion due to left heart failure affect the lungs?
A
- pulmonary congestion and oedema
- heart failure cells
12
Q
What are heart failure cells?
A
Siderophages generated in the alveoli of patients with left heart failure
High pulmonary blood pressure causes red cells to pass through the vascular wall and encounter macrophages.
13
Q
What are the symptoms caused by the congestion in left heart failure?
A
- dyspnoea
- orthopnoea
- PND (parxoysmal nocturnal dyspnoea)
- blood tinged sputum
- cyanosis
- elevated pulmonary wedge pressure (PCFP) (nl = 2-15mmHg)
14
Q
Orthopnoea is a symptom of left heart failure. What is it?
A
Shortness of breath which occurs when lying flat, causing the person to have to sleep propped up in bed or sitting in a chair
15
Q
PND is a symptom of left heart failure. What is it? (paroxysmal nocturnal dyspnoea)
A
Attacks of severe shortness of breath and coughing that generally occur at night. It usually awakens the person from sleep, and may be quite frightening
16
Q
What is pulmonary wedge pressure? (elevated in left heart failure)
A
The pressure measured by wedging a pulmonary catheter with an inflated balloon into a small pulmonary arterial branch
Because of the large compliance of the pulmonary circulation, it provides an indirect measure of the left atrial pressure
17
Q
What is the aetiology of right sided heart failure?
A
- left heart failure
- cor pulmonale
18
Q
What is cor pulmonale?
A
Enlargement and failure of the right ventricle of the heart as a response to increased vascular resistance or high blood pressure in the lungs
19
Q
What are the symptoms/signs of right heart failure related to the liver and spleen?
A
- passive congestion (nutmeg liver)
- congestive splenomegaly
- ascites
20
Q
What is nutmeg liver?
A
Congestive hepatopathy
Sign of right heart failure
Liver dysfunction due to venous congestion
21
Q
What is ascites?
A
Accumulation of fluid in the peritoneal cavity, causing abdominal swelling
22
Q
What is congestive splenomegaly?
A
Splenomegaly secondary to portal hypertension, with ascites, anemia, thrombocytopenia, leukopenia, and episodic hemorrhage from the intestinal tract. Called also Banti’s disease.
23
Q
Which parts of the body are affected by right heart failure?
A
- liver
- spleen
- kidneys
- pleura/pericardium
- peripheral tissues
24
Q
How does right heart failure affect the pleura/pericardium?
A
- pleural and pericardial effusions
- transudates
25
What are the general symptoms and signs of right heart failure?
- fatigue
- dependent oedema
- distention of the jugular veins
- liver engorgement
- ascites
- anorexia and complaints of GI distress
- cyanosis
- elevation in peripheral venous pressure
26
What are the general autopsy findings in chronic heart failure?
- cardiomegaly
- chamber dilatation
- hypertrophy of myocardial fibres
- boxcar nuclei
27
What are the 2 main categories of valvular heart disease?
- opening problems (stenosis)
| - closing problems (regurgitation, or incompetence of insufficiency)
28
Which conditions make up 70% of valvular heart disease?
- aortic stenosis
| - mitral stenosis
29
What is aortic stenosis?
Calcification of a deformed aortic valve
30
Why might calcification of the aortic valve occur?
- "senile" calcification (just with old age)
| - may be part of rheumatic heart disease
31
Why might mitral stenosis occur?
Rheumatic heart disease
32
What is rheumatic heart disease?
Occurs in cases of rheumatic fever (a serious complication). Follows a group A strep infection (a few weeks later).
Inflammation causes the heart's valves to become damaged and stiffened
33
How has the epidemiology of rheumatic heart disease changed?
Decrease in developed countries
34
What are the different types of carditis (inflammation of the heart)?
Pancarditis = inflammation of the entire heart
Endocarditis = inflammation of the endocardium
Myocarditis = inflammation of the heart muscle
Pericarditis = inflammation of the pericardium
35
What are the findings in acute rheumatic heart disease?
- inflammation
- Aschoff bodies
- Anitschkow cells
- pancarditis
- vegetations on chordae tendinae at leaflet junction
36
What are Aschoff bodies?
- nodules found in the hearts of individuals with rheumatic fever
- result from inflammation in the heart muscle
37
What are Anitschkow cells?
- often associated with rheumatic heart disease
| - enlarged macrophages found within granulomas (Aschoff bodies)
38
What are the findings in chronic rheumatic disease?
- thickened valves
- commisural fusion
- thick, short chordae tendinae
39
What are the clinical features of aortic stenosis?
- 2x gradient pressure
- left ventricular hypertrophy but no hypertension
- ischaemia
- cardiac decompensation
- angina
- chronic heart failure
40
What is the prognosis in aortic stenosis?
50% die in 5 years if angina present
50% die in 2 years if chronic heart failure present
41
What is mitral annular calcification?
Calcification of the mitral "skeleton"
Degenerative process involving the fibrous annulus of the mitral valve.
42
Is mitral annular calcification symptomatic?
Usually no dysfunction
Generally an incidental finding associated with ageing
But occasionally prominent enough to cause significant left ventricular inflow obstruction and symptomatic mitral stenosis
43
Is mitral annular calcification more common in males or females?
Females
44
Does mitral annular calcification cause stenosis or regurgitation?
Regurgitation usually, but stenosis is possible
45
What are the different causes of aortic regurgitation?
- rheumatic disease
- infectious
- aortic dilatations (syphilis, rheumatoid arthritis, marfan)
46
What are the different causes of mitral regurgitation?
- infectious
- fen-phen
- problems with papillary muscles and/or chordae tendinae
- calcification of the mitral ring (annulus)
47
What is mitral valve prolapse (MVP)?
Myxomatous degeneration of the mitral valve
"floppy valve"
Characterised by displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole
48
What is mitral valve prolapse associated with?
Connective tissue disorders
49
Describe the incidence of mitral valve prolapse
3% incidence. F > M
50
How is metal valve prolapse detected?
Easily seen on echocardiogram
51
Mitral valve prolapse involves myxomatous degeneration. What is this?
Pathological weakening of connective tissue
52
What are the clinical features of mitral valve prolapse?
- usually asymptomatic
- mid-systolic "click"
- holosystolic murmur if regurgitation is present
- occasional chest pain and dyspnoea
- 97% no untoward effects
- 3% infective endocarditis, mitral insufficiency, arrhythmias, sudden death
53
What are congenital heart defects due to?
Fault embryogenesis (weeks 3-8)
May not be evident until adult life (coarctation, ASD)
54
Are congenital heart defects usually mono-morphic or dimorphic?
Usually mono-morphic eg. single lesion eg. ASD, VSD, hypo-RV, hypo-LV)
55
What is the incidence of congenital heart defects?
Overal incidence = 1% of births
56
What makes up the biggest proportion of congenital heart defects?
Ventricular septal defect (42%)
57
After ventricular septal defect, what is the next most common congenital heart defect?
Atrial septal defect (10%)
58
After ventricular septal defect and atrial septal defect, what are some other relatively common congenital heart defects?
- pulmonary stenosis (8%)
- patient ductus arteriosus (7%)
- tetralogy of fallot (5%)
- coractation of the aorta (5%)
59
Give some of the less common congenital heart defects
- atrioventricular septal defect (4%)
- aortic stenosis (4%)
- transposition of great arteries (4%)
- total anomalous pulmonary venous connection (1%)
- triscuspid atresia (1%)
60
Which conditions are involved in a left-to-right shunt?
- ventricular septal defect
- atrial septal defect
- patient ductus arteriosus
- atrioventricular septal defect
61
Which conditions are involved in a right-to-left shunt?
- tetralogy of fallot
- transposition of great arteries
- truncus arteriosus
- total anomalous pulmonary venous connection
- tricuspid atresia
62
Which direction of shunting causes cyanosis ("blue" babes)?
Right to left.
| blood missing out the lungs and so is reaching the rest of the body without being oxygenated
63
What is tricuspid atresia?
Complete absence of the tricuspid valve. Therefore, there is an absence of right atrioventricular connection. This leads to a hypoplastic (undersized) or absent right ventricle
Blocks blood flow from the right atrium to the right ventricle
64
What are the 4 components of tetralogy of fallot?
- ventricular septal defect
- pulmonary stenosis
- overriding aorta
- right ventricular hypertrophy
65
In what proportion of congenital heart defects are there gene abnormalities?
10%
66
Trisomies of which chromosomes may contribute to congenital heart defects
Trisomies 21, 13, 15, 18, XO
67
Give some examples of genes which encode for transcription factors which mutations of may cause congenital heart defects
TBX5 - ASD, VSD
NKX2.5 - ASD
68
Which part of the genome is important in heart development?
Region of chromosome 22 (22q11.2)
Deletion - conotruncus, branchial arch, face
69
Name 2 environment factors that play a part in congenital heart defects
- rubella
| - teratogens
70
Briefly describe the development of the atrial septum
- septum secundum grows down the right hand side of the septum primum
- septum has semilunar shape and its border delineates the foramen oval
- blood may pass from right atrium to left atrium in the foetal period through foramen oval and ostium secundum
71
Briefly describe the development of the aorticopulmonary septum
- septum divides bulbus cordis and truncus into 2 main arterial trunks (aorta and pulmonary artery)
- has a spiral path that results in final topographical relations of both vessels
72
Name 5 different types of septal defects
- atrial septal defect (ASD)
- ventricular septal defect (VSD)
- patent ductus arteriosus (PDA)
- complete atrioventricular canal defect
- large VSD with irreversible pulmonary hypertension
73
What are the clinical features of left-to-right shunts? (Ds in the names)
- NO cyanosis
- pulmonary hypertension
- significant pulmonary hypertension is irreversible
74
What are the clinical features of right-to-left shunts? (Ts in the names)
- cyanosis (blue babies)
| - venous emboli become systemic "paradoxical"
75
What is the most feared consequence of left-to-right shunts?
Irreversible pulmonary hypertension
76
What are the different types of atrial septum defect?
Secundum (90%) = defective fossa ovalis
Primum (5%) = next to AV valves, mitral cleft
Sinus venosus (5%) = next to SVC with anomalous pulmonary veins draining to SVC or RA
77
What are the symptoms of ASD?
Usually asymptomatic until adulthood
78
Are VSD isolated or associated with other things?
- only 30% are isolated
| - often with tetralogy of fallot
79
In VSD, is the membranous or the muscular septum involved?
90% involve the membranous septum
If muscular septum is involved, it can have multiple holes ("swiss-cheese" septum)
80
What are the prognoses of VSD depending on size?
Small ones often close spontaneously
Large ones progress to pulmonary hypertension
81
Are PDA isolated or associated with other things?
- 90% are isolated
| - associated with VSD, coarctation of the aorta, pulmonary and aortic stenosis
82
In PDA, is the shunt left to right or right to left?
Left to right
Can become right to left as pulmonary hypertension increases and reaches systemic pressure
83
What is done in the case of PDA?
Closing the defect in early life may be life saving in isolated PDA
84
What is used to prevent premature closure of the ductus arteriosus in certain newborns?
Prostaglandin E1
85
Why might the ductus arteriosus be needed to be kept patent?
In some congenital heart defects eg. transposition of the great vessels) a PDA may need to remain open, as it is the only way that oxygenated blood can mix with deoxygenated blood. In these cases, prostaglandins are used to keep the DA open until surgical correction of the heart defect is completed
86
What kind of murmur do you get in patent ductus arteriosus?
Continuous harsh, machinery-like murmur
87
What are the clinical features of AVSD?
- associated with defective, inadequate AV valves
- can be partial or complete (all 4 chambers freely communicate)
- more than a 3rd with complete AVSD have Down syndrome
88
Which is the most common condition with right-to-left shunting?
Tetralogy of Fallot
89
In tetralogy of Fallot, there is a large VSD, RVH, obstruction to RV outflow and an overriding aorta. What is an overriding aorta?
The aorta overrides the ventricular septal defect
90
What does survival depend on in tetralogy of Fallot?
Depends on severity of subpulmonic stenosis
91
What is a "pink" tetralogy? (tetralogy of Fallot)
When the pulmonic obstruction (pulmonary stenosis) is small, but the greater the obstruction, the greater the right-to-left shunt
92
What is transposition of the great arteries?
Group of congenital heart defects involving an abnormal spatial arrangement the pulmonary artery and aorta.
Abnormal formation of the truncal and aortopulmonary septa - needs a shunt for survival
93
Transposition of the great arteries requires a shunt for survival. Which shunts occur?
- PDA or PFO (65%) = unstable shunt
| - VSD (35%) = stable shunt
94
What is the difference in thickness of the ventricles in transposition of the great arteries?
RV > LV in thickness
95
How is transposition of the great arteries repaired?
Surgical "switching"
- aorta moved from right ventricle to its normal position over left ventricle.
- pulmonary artery moved from left ventricle to its normal position over the right ventricle
Other defects eg. ASD/VSD/PSA closed
96
If transposition of the great arteries fatal?
Fatal in first few months
Requires surgical "switching"
97
What is truncus arteriosus?
Single blood vessel (truncus arteriosus) comes out of the right and left ventricles, instead of the normal two vessels (pulmonary artery and aorta)
Developmental failure of separation of truncus arteriosus
98
What are the features of truncus arteriosus?
- aorta and pulmonary artery joined
- associated VSD
- produces systemic cyanosis and well as increased pulmonary blood flow
99
What are the clinical features of tricuspid atresia?
- hypoplastic right ventricle (undersized)
- needs a shunt (ASD/VSD/PDA)
- high mortality
100
What are the features of total anomalous pulmonary venous connection (TAPVC)?
- pulmonary veins do not go into the left atrium as normal, but go into left innominate vein or coronary sinus
- needs a PFO or VSD
- hypoplastic left atrium
101
Name 3 types of OBSTRUCTIVE congenital heart disease
- coarctation of the aorta
- pulmonary stenosis/atresia
- aortic stenosis/atresia
102
What are the 2 forms of coarctation of the aorta?
- infantile form (proximal to PDA, serious!)
| - adult form (closed ducts - no PDA)
103
What is also present in 50% of cases of coarctation of the aorta?
Bicuspid aortic valve
104
Is coarctation more common in males or females?
Males
105
What are the clinical features of pulmonic stenosis/atresia?
- if 100% atretic, hypoplastic right ventricle with ASD
| - clinical severity correlated with stenosis severity
106
What are the 3 types of aortic stenosis?
- valvular
- sub-valvular
- supra-valvular
107
What happens in valvular aortic stenosis?
If severe, you have a hypoplastic left ventricle which can be fatal
108
What is sub-valvular/sub-aortic aortic stenosis?
Aortic wall thick below the cusps
109
What is supra-valvular aortic stenosis?
Aortic wall thick above the cusps in ascending aorta
