2. Arrythmias, Heart Failure, Hypertension and Valvular Disease Flashcards
- What 2 things determine cardiac output?
2. Name three things that also influence cardiac output
- stroke volume and heart rate
2. venous return, peripheral vascular tone and neurohumoral factors
- What is preload?
2. What is preload determined by? (2)
- end diastolic volume (represents stretch within heart)
2. duration of diastole; venous return
- What is afterload?
2. What is cardiac reserve?
- force resisting myocardial contraction at the start of systole. related to systolic blood pressure
- the ability of the heart to increase performance above resting levels
- What is the mechanism of heart failure with reduced ejection fraction?
- What happens to diastolic volume and pressure in this heart failure?
- What is this type of heart failure common following?
- ventricle contracts poorly and empties inadequately
- both increase
- MI and dilated cardiomyopathy
- What is the mechanism of heart failure with preserved ejection fraction?
- Why is ejection fraction preserved?
- What does this type of heart failure result from?
- ventricles are stiffened, with decreased compliance and impaired relaxation. This causes impaired ventricular filling and thus inadequate stroke volume
- contraction is normal, but the amount of blood in the heart at the end of diastole is reduced so therefore cardiac output is reduced
- increased ventricular stiffness or valvular disease
- how does the myocardium respond to heart failure?
- How does ventricular dilation worsen heart failure?
- How is cardiac reserve lost in heart failure?
- reduction in ejection fraction > increased volume of blood left in the heart following systole > stretch > further reduction in ventricular function
- increased ventricular radius > increased myocardial wall tension > increased work of heart to overcome tension
- heart works harder to meet normal metabolic demands therefore the amount cardiac output increases in times of increased oxygen demand is reduced.
- How does the sympathetic nervous system respond to heart failure?
- What are the consequences of this?
- increased sympathetic output due to reduced systemic BP > Increased HR & myocardial contracility and vasoconstriction
- increased cardiac work, increased preload, increased afterload
- How does the RAAS system respond to heart failure?
2. What are the consequences of this?
- reduced renal perfusion > decreased GFR > activation of RAAS
- vasoconstriction, sodium and water retention, sympathetic stimulation
What is alcoholic cardiomyopathy?
condition where chronic use of alcohol leads to heart failure. Type of dilated cardiomyopathy
Name 4 symptoms of heart failure
- exertional dyspnoea
- orthopnoea
- paroxysmal nocturnal dyspnoea
- fatigue
Name 7 signs of heart failure
- tachycardia
- elevated JVP
- cardiomegaly
- bibasal crackles
- peripheral oedema
- third heart sound
- anasarcia
- How is pulmonary oedema acutely managed?
- In a patient with pulmonary oedema, what is given if they are in cardiogenic shock?
- How is pulmonary oedema managed in the long term
- oxygen, IV furosemode, opiates
- dobutamine
- oral diuretics, ACE inhibitors, beta blockers
Name investigations that are performed for ?Heart failure
- serum electrolytes
- renal function tests
- NT-pro-BNP
- CXR
- Electrocardiogram
What is the triple therapy for the management of chronic heart failure?
ACE inhibitor/ARB
Beta Blocker
Aldosterone antagonist
- What is CRT-P?
2. What is CRT-D?
- internal pacemaker
2. pacemaker + defibrilator
Name the 2 things that determine blood pressure
cardiac output (dependent on heart rate, myocardial contractility and diastolic blood volume) peripheral resistance
- What blood pressure is classified as hypertension?
2. What blood pressure is classified as severe hypertension?
- > 140/90
2. >180/120
- Name 2 types of patients in which isolated systolic hypertension can be seen?
- In what condition cam isolated diastolic hypertension be seen?
- elderly; hyperthyroidism
2. aortic regurgitation
- What is a hypertensive urgency?
- What is a hypertensive emergency?
- What is malignant hypertension?
- severe hypertension, but with no evidence of end organ damage
- severe hypertension, with evidence of end organ damage
- severe hypertension and retinal haemorrhage and/or papilloedema
What 2 criteria describe resistant hypertension?
- blood pressure that remains above target despite 3 different antihypertensive medications, one of which is a diuretic
- blood pressure that is at target with 4 different antihypertensive medications, one of which is a diuretic
- What occurs in the early phase of essential hypertension?
2. What occurs in the chronic phase of essential hypertension?
- increased blood volume and cardiac output drives hypertension
- thickened wall of resistance vessels increases vascular resistance; blood volume and cardiac output normal
Name 5 causes of secondary hypertension
- renal artery stenosis - poor renal perfusion > activation of RAAS
- chronic renal disease - increase in BP to restore GFR
- primary hyperaldosteronism - overproduction of aldosterone > sodium and water retention
- phaeochromocytoma - adrenal medulla tumours secrete catecholamines > alpha mediated vasoconstriction and beta mediated cardiac stimulation
- Coarctation of the aorta - results in renal hypoperfusion
Name 4 instances where you should be suspicious of secondary hypertension
- renal dysfunction
- young
- severe treatment resistnace
- hypokalaemia (indicates mineralocorticoid excess)
describe the ECG trace of normal sinus rhythm (P waves)
- upright p waves in leads I and III
- inverted p waves in aVR and V1