Cardiovascular diseases 2 Flashcards
What 5 things characterize the hypertrophy and/or dilation of the heart in left sided heart failure?
1) Increased heart size and mass
2) Increased protein synthesis
3) Abnormal proteins
4) Fibrosis
5) Inadequate vasculature
What 3 things is the cardiac dysfunction in left sided heart failure characterised by?
1) heart failure (systolic/diastolic)
2) Arrhythmias
3) Neurohumoral stimulation
What are the 6 main steps in the pathogenesis of left sided heart failure?
1) Increased cardiac work
2) Increased wall stretch
3) Cell stretch
4) Hypertrophy and/or dilation
5) Cardiac dysfunction
What 3 things can lead to increased cardiac work (leading to left sided heart failure)?
1) Hypertension - pressure overload
2) Valvular disease - pressure and/or volume overload
3) MI - regional dysfunction with volume overload
Left sided heart failure (low output) affects what 3 organs particularly?
1) Kidneys
2) Brain
3) Lungs
What effects does left sided heart failure have on the kidneys? 2
1) Pre-renal azotemia - It is an excess of nitrogen compounds in your blood stream due to a lack of blood flow to each kidney
2) Salt and fluid retention - RAAS activation, natriuretic peptides
What effect does left sided heart failure, thus low output, have on the brain? 3
1) Irritability
2) Decreased attention
3) Stupor (state of near-consciousness) -> coma
What effect does left sided heart failure have on the lungs?
Pulmonary congestion and edema
What are the 6 possible pulmonary symptoms of left sided heart failure?
1) Dyspnea
2) Orthopnea
3) PND (paroxysmal nocturnal dyspnea)
4) Blood tinged sputum
5) Cyanosis
6) Elevated pulmonary WEDGE pressure (pressure measured by wedging a catheter in pulmonary artery)
What are the 2 main causes of right sided heart failure?
1) Left sided heart failure
2) Cor pulmonale - abnormal enlargement of right side of heart due to disease of the lungs or pulmonary blood vessels
In which 5 organs can the signs and symptoms of right sided heart failure be seen?
1) Liver
2) Spleen
3) Kidneys
4) Pleura/pericardium
5) Peripheral tissues
What are the symptoms or signs seen in the liver/spleen in right sided heart failure? 3
1) Passive congestion/ nutmeg liver - liver dysfunction due to venous congestion
2) Congestive splenomegaly
3) Ascites
What 2 signs can be seen in the pleura/pericardium in right sided heart failure?
1) Pleural and pericardial effusions
2) Transudates (extravascular fluid with low protein content)
What are the 3 main autopsy findings in congestive heart failure?
1) Cardiomegaly
2) Chamber dilatation
3) Hypertrophy of myocardial fibres - BOXCAR nuclei
What is valvular heart disease?
Opening problems - stenosis
and Closing problems (incompetency or insufficiency) - regurgitation
70% of all valvular heart disease is attributable to which 2 conditions?
1) Aortic stenosis - calcification of deformed valve
2) Mitral stenosis
What are the 2 main causes of aortic stenosis?
1) ‘Senile’ calcific aortic stenosis
2) Rheumatic heart disease
What is the main cause of mitral stenosis?
Rheumatic heart disease
What is rheumatic heart disease?
Follows a group A strep pharyngitis - get pancarditis (endocarditis + myocarditis + pericarditis)
What are the 5 signs of acute rheumatic heart disease?
1) Inflammation
2) Aschoff bodies
3) Anitschkow cells
4) Pancarditis
5) Vegetations on chordae tendinae at leaflet junction
What are the 3 signs of chronic rheumatic heart disease?
1) Thickened valves
2) Commisural fusion
3) Thick, short chordae tendinae
What changes in the heart does aortic stenosis initially lead to?
1) Left ventricular hypertrophy (but no hypertension)
2) Ischemia
Which 2 conditions does aortic stenosis lead to?
1) Angina
2) CHF
What is the prognosis of aortic stenosis?
50% die in 5 years if angina is present
50% die in 2 years if CHF is present
What is mitral annular calcification, how does this affect the function of the mitral valve?
- Calcification of the mitral skeleton
- Usually no dysfunction
- Regurgitation usually but stenosis is possible
Is mitral annular calfication more common in males or females?
Females
What are the 2 types of regurgitation?
1) Aortic regurgitations
2) Mitral regurgitations
What are the 3 main causes of aortic regurgitations?
1) Rheumatic
2) Infectious
3) Aortic dilatations (syphilis, rheumatoid arthritis, marfan)
What are the 5 main causes of mitral regurgitations?
1) Infectious
2) Fen-Phen (obesity drug)
3) Papillary muscles/ chordae tendinae dysfunction
4) Calcification of mitral ring (annulus)
5) Mitral valve prolapse
What is a mitral valve prolapse?
Myxomatous (pathological weakening of connective tissue) degeneration of mitral valve
Associated with connective tissue disorders
Floppy valve
What imaging technique can be used to see a mitral valve prolapse?
Echocardiogram
Is a mitral valve prolapse more common in males or females?
Females
What 4 possible complications is mitral valve prolapse associated with?
1) Infective endocarditis
2) Mitral insufficiency
3) Arrhythmias
4) Sudden death
Does mitral valve prolapse usually have any symptoms?
No, usually asymptomatic, 97% of sufferers have no untoward effects
What are the 4 possible symptoms of mitral valve prolapse?
1) Mid systolic click
2) Holosystolic murmur if regurgitation is present
3) Occasional chest pain
4) Dyspnea
Congenital heart defects affect what percentage of the births?
1%
Congenital heart defects are due to faulty embryogenesis when?
Weeks 3-8
Which 4 congenital heart defects cause a left to right shunt?
1) Ventricular septal defect
2) Atrial septal defect
3) Patent ductus arteriosus
4) AV septum defect
Name 3 congenital heart defects which cause no shunt?
1) Aortic stenosis
2) Pulmonary stenosis
3) Coarctation of the aorta
Which 5 congenital heart defects cause a right to left shunt?
1) Tetralogy of Fallot
2) Transposition of great arteries
3) Truncus arteriosus (single blood vessel out of R&L ventricles)
4) Total anomalous pulmonary venous connection
5) Tricuspid atresia (complete absence of tricuspid valve - absent right ventricle)
In what percentage of congenital heart defects are there gene abnormalities?
10%
Which region of the genome is particularly important in heart development?
Region of Chr22 - 22q11.2
What are the 2 most common genetic abnormalities in congenital heart disease?
Trisomies - 21, 13, 15, 18, XO
Mutations in genes encoding for transcription factors, TBX5, NKX2.5
Which 2 environmental factors can lead to congenital heart defects?
1) Rubella
2) Tetratogens
What is the function of the foramen ovale in the fetal period and what is it formed from?
Allow passage of blood from right atrium to left atrium as lungs have no function in oxygenating blood in fetal period
- Between the spetum primum and septum secundum - forming the interatrial septum
What are the final stages in the formation of the pulmonary artery and the aorta in utero?
1) Septum divides the bulbus cordis and truncus of the primitive heart into 2 main arterial trunks - the aorta and pulmonary artery
2) It has a spiral path resulting in the normal anatomy of the vessels
What are the signs of Left to right shunts? 2
1) No cyanosis
2) Pulmonary hypertension
What are the 2 signs of right to left shunts? 2
1) Cyanosis
2) Venous emboli become systemic
What is the most feared consequence of left to right shunts?
Irreversible pulmonary hypertension
Are atrial septal defect and patent foramen ovale the same?
No
When do symptoms of atrial septal defect usually become apparent?
Adulthood
What percentage of ASDs are defects of the septum secundum?
90% - tend to be defective fossa ovalis
What percentage of ASDs are defects of the septum primum?
5% - tend to be next to AV valves, mitral valve cleft
What is the 3rd type of atrial septal defect?
Sinus venosus atrial septal defect - accounts for 5%
What is the most common congenital heart defect?
Ventricular septal defect
What percentage of VSDs are isolated, what is it often associated with?
30% - often associated with tetralogy of fallot
What part of the VS is most commonly affected in VSDs?
Membranous septum - 90%
What is distinctive about VSDs of the muscular septum?
Often have multiple holes
What is the difference in effect of small and large VSDs?
Small holes often close spontaneously
Large one progress to pulmonary hypertension (L ->R shunt)
What percentage of patent ductus arteriosus are isolated?
90%
What 4 other congenital heart defects is a patent ductus arteriosus associated with?
1) VSD
2) Coarctation of the aorta
3) Pulmonary stenosis
4) Aortic stenosis
Does a patent ductus arteriosus cause a L->R or R->L shunt?
Left to right but can go right to left as pulmonary hypertension approaches systemic pressure
What is the possible life saving treatment for a patent ductus arteriosus?
Closing the defect early in life
In what situation could treating a patent ductus arteriosus with prostaglandins to keep it open be life saving?
In coarctation of the aorta (pre ductal coarctation)
What heart sound is heard in a patent ductus arteriosus?
Continuous, harsh, machinery like murmur
Atrioventricular septal defects are associated with what?
Defective, inadequate AV valves
What syndrome are complete AVSDs associated with?
Down syndrome
What are the 2 types of AVSD?
1) Partial
2) Complete - all chambers freely communicate
What 4 things is tetralogy of fallot made up of?
1) VSD - large
2) Obstruction to RV outflow (pulmonary stenosis)
3) Aorta overrides the VSD
4) RV Hypertrophy
What does survival in tetralogy of fallot depend on?
Severity of the pulmonary stenosis - this determines the extent of R -> L shunt
What is ‘pink’ tetralogy of fallot?
When pulmonic obstruction is small,
What is transposition of the great vessels?
Abnormal formation of truncal and aortopulmonary septa
What is require for survival in transposition of the great vessels?
A shunt - but it is fatal in the first few months of life if not treated with surgical switching
Other than the obvious abnormality, how is the structure of the heart abnormal in transposition of the great vessels?
Right ventricle is thicker than the left ventricle
What is truncus arteriosus?
Developmental failure of separation of truncus arteriosus into 2 vessels
What other defect is TA associated with?
VSD
What are the 2 signs of TA?
1) Systemic cyanosis
2) Increased pulmonary blood flow
What is tricuspid atresia, what must it be associated with for survival?
Hypoplastic RV - basically only have one ventricle
Must be associated with a shunt for survival - high mortality
What is total anomalous pulmonary venous connection (TAPVC)
Pulmonary veins do not go into LA but go into innominate LV or coronary sinus, hypoplastic left atrium
What does TAPVC need to be associated with for survival?
Patent foramen ovale or VSD
What are the 3 obstructive congenital heart defects?
1) Coarctation of the aorta
2) Pulmonary stenosis/ atresia (pulmonary valve not formed properly)
2) Aortic stenosis/ atresia
Is coarctation of the aorta more common in males or females?
Males
Coarctation of the aorta is associated with what valvular abnormality in 50% of cases?
Bicuspid aortic valve
What are the 2 forms of coarctation of the aorta?
1) Infantile form (proximal to PDA) - serious
2) Adult form (closed ductus arteriosis ie. no PDA)
What are the 3 types of aortic stenosis?
1) Valvular - if severe with a hypoplastic LV = fatal
2) Sub valvular (sub aortic) - aortic wall thick below cusps
3) Supra-vavlular - aortic wall thick above cusps in ascending aorta
