Cardiovascular Flashcards
(23 cards)
Where is tear in aortic dissection?
Tunica intima of the wall of the aorta
What is the normal resting membrane potential of the heart’s ventricular and atrial fibres?
Approximately -90mV in the ventricular fibres and -80mV in the atrial fibres
Down’s syndrome is associated with what congenital heart anomaly?
Ventricular septal defect
What are features of aortic regurgitation?
- Early diastolic murmur
- Collapsing pulse - The carotid pulse rises rapidly due to the vigorous ejection of blood from an overloaded left ventricle. It then falls rapidly due to the backflow of blood into the left ventricle.
- Wide pulse pressure
What effect does increased stroke volume have on pulse pressure?
Increases pulse pressure
What is arrhythmogenic right ventricular cardiomyopathy characterised by?
Right ventricular myocardium replaced by fatty and fibrofatty tissue
An undersized blood pressure cuff may lead to an _____ of blood pressure
overestimation
What is torsades de pointes a form of?
Polymorphic ventricular tachycardia
What medication is used first-line for reducing stroke risk in AF?
DOACs such as edoxaban
From where do the internal thoracic arteries arise from?
The subclavian arteries
What is the mechanism of action of nitrate drugs?
Nitrates can cause a decrease in intracellular calcium, due to release of nitric oxide. This nitric oxide activates guanylate cyclase to convert GDP to cGMP. Decreased intracellular calcium within smooth muscles causes relaxation of vascular smooth muscle.
What are ECG findings of Wolff-Parkinson-White syndrome?
- Delta wave - slurred upstroke of QRS complex
- Short PR interval
What is a range of normal stroke volumes?
55-100ml
What is S4 caused by?
The atria contracting forcefully in an effort to overcome an abnormally stiff ventricle
What are potential treatment options for postural hypotension?
- Midodrine
- Fludrocortisone
What process (not specific to vasculature) is mediated by a2 adrenoceptors?
Platelet aggregation
What is a normal ejection fraction range?
50-55%
At which point of the cardiac cycle does the highest volume of blood flow through the coronary arteries and why?
Ventricular diastole - During diastole, the backflow of blood from the aorta to the left ventricle causes the aortic valve to close. The cusps of the aortic valve hence move away from the openings of the coronary arteries and therefore allow blood into the coronary arteries, so blood flow is highest during ventricular diastole.
Which phase of the cardiac cycle does the beating of the carotid/radial pulse correspond with?
Ventricular systole
In aortic pressure tracings, an incisura or dicrotic notch is seen at the end of systole.
What is the cause of this dicrotic notch?
The closure of the aortic valve
What is the effect of BNP on preload and afterload?
Decreases both
How does BNP decrease afterload?
By decreasing SVR
How does BNP decrease preload?
By increasing diuresis which leads to a reduction in blood venous volume and hence reduces preload
