Lecture 4 CVD Theme - Ageing Heart Muscle and Heart Failure Flashcards
What measures several components of cardiac function and metabolism?
Cardiac MRI
What is the blood pool volume?
the volume of blood in the left ventricle
What changes to diastole are made when you age?
Delayed early phase but late phase increased as left atrium squeezes to get more blood.
What do people with hypertension have?
Impaired diastolic function as relaxation is delayed.
What is HF rEF?
Heart failure with reduced ejection fraction (how much blood is pumped per cycle).
Systolic dysfunction.
What is HF pEF?
Heart failure with preserved ejection fraction.
Diastolic dysfunction.
How is neurohormonal activation in HF rEF initially beneficial?
Activation of the sympathetic NS and the renin-angiotensin-aldosterone system leads to compensatory increase in neurohormones, maintaining arterial BP.
How do the beneficial effects of neurohormones eventually become chronic?
Over a long period of time their effects become deleterious and contribute to salt and water retention and progressive LV remodelling and dysfunction.
What are the chronic effects of neurohormonal activation?
Increased after load, reduced stroke volume, myocyte necrosis and apoptosis, sodium retention.
What causes HF years after insult?
Reduced CO makes body think it is in a chronic state of shock > chronic neurohormonal stimulation > affects other parts of the heart that were healthy after MI > vicious cycle.
What are some treatments for HF rEF?
Angiotensin converting enzyme inhibitors.
B-blockers.
What do angiotensin converting enzyme inhibitors do?
inhibits conversion of angiotensin I to angiotensin II, lowering BP as veins and arteries relax.
What do B-blockers do?
Inhibits B-adrenergic receptors on myocytes.
Long term inhibition of neurohormonal activation.
What are some difficulties with HF therapies?
Reduced BP
Multiple medications that are hard to manage
Electrolytes and renal function must be closely monitored
Co-ordinated care needed
