Cardiovascular Pathology Flashcards
What are the different types of cardiac myocytes?
Atrioventricular conduction system and general cardiac myocytes
Is blood flow through myocardium from aortic root diastolic or systolic?
Diastolic
What is the normal systolic ejection fraction?
60-65%
What is cardiac failure?
Failure to transport blood out of the heart
What is cardiogenic shock?
Severe cardiac failure
What is the Frank Starling mechanism?
The stroke volume of the left ventricle will increase as the left ventricular volume increases due to the myocyte stretch causing a more forceful systolic contraction
What are the pericardial sac limitations?
The pericardium is relatively inelastic and non-compliant, the pericardium limits the total volume of the contained cardiac chambers and pericardial fluid
Which pericardial layer mediates the pericardial sac limitations the most?
The visceral pericardium
What happens when the stretch capabilities of the sarcomeres are exceeded?
Cardiac contraction force diminishes and which leads to hypertrophy
What can trigger the hypertrophic response?
Angiotensin II, ET-1 (endothelin 1), IGF-1, TGF-beta
What does the activation of Angiotensin II/ET-1/IGF-1/IGF-beta do in terms of hypertrophy?
They activate mitogen activated protein kinase
What does mitogen activated protein kinase do ?
Mediate intracellular signaling involved in regulating protein and cell functioning related to membrane, intra- and intercellular processes and transformation, proliferation/growth, differentiation, survival, and death
What does left sided cardiac failure result in?
Pulmonary congestion, overload of right side
What does right sided cardiac failure cause?
Venous hypertension and peripheral congestion
What does diastolic cardiac failure result in?
A stiffer heart
When does the foetal heart develop?
Week 5
What happens in foetal heart development?
In week 5, from the endocardial cushions, the intraventricular and intra atrial septa develop. The muscular intraventricular septum grows upwards from the apex of the heart producing 4 chambers allowing for valve development
What is a congenital heart disease?
A disease from birth that results in the misplacement of structures or arrest of progression of normal structure development
Give 4 examples of congenital heart disease
VSD (ventricular septal defect), ASD (atrial septal defect), PDA (patent ductus arteriosus), Fallots, PS (pulmonary valve stenosis), coarctation, AS (aortic valve stenosis), TGA (Transposition of the great arteries), truncus arteriosus, trucuspid atresia
What type of inheritance is shown by these congenital heart defects?
Multifactorial inheritance
What genes are associated with congenital heart defects?
Single genes Trisomy 21 Turners syndrome XO Di-george syndrome Homeobox genes - large group of similar genes that direct the formation of many body structures during early embryonic development
What infections are associated with congenital heart defects?
Rubella
What drugs are associated with congenital heart defects?
Thalidomide - leprosy Alcohol Phenytoin - epilepsy Amphetamines Lithium - depression, bi polar Oestogenic steroid
What conditions are associated with congenital heart defects?
Diabetes
