Valvular Disorders & Heart Failure Flashcards
How is cardiac output calculated?
Stoke volume x heart rate
What is cardiac output
The volume of blood the heart pumps in a minute
What units is cardiac output usually given in?
L/min
How is ejection fraction calculated?
(stroke volume/ end diastolic volume) x100
What is ejection fraction?
The volumetric fraction of blood ejected by the ventricle
What units is ejection fraction given in?
%
What are the 2 ways mean arterial pressure calculated?
Cardiac output x systemic vascular resistance + central venous pressure
OR
diastolic pressure + 1/3( systolic pressure- diastolic pressure)
What is mean arterial pressure?
Average arterial pressure through a single cardiac cycle
What are the units of mean arterial pressure?
mm Hg
What should mean arterial pressure be for there to be adequate perfusion?
65 mm Hg or above
Define infective endocarditis
Fever and new heart murmur
What is infective endocarditis?
Infection of the endocardium
What is the endocardium?
The innermost lining of the heart
How many layers are there in the lining of the heart? What are they called?
There are 3, from innermost to outermost they are:
Endocardium
Myocardium
Pericardium
What is the most common cause of infective endocarditis?
Streptococcus
How will patients with infective endocarditis present?
Fever, malaise, breathlessness, chest pain, fatigue, coughing (general signs of cardiac decomposition)
What set of criteria are used to diagnose infective endocarditis?
Duke’s criteria
What part of the heart does infective endocarditis most effect?
The left side and its valves (mitral and aortic) as this is where most blood flows
How are IV drug users a concern in infective endocarditis?
They are at higher risk due to frequent intravenous injections- they may also present irregularly with more right sided problems as when injected, this is the first place bacteria in the blood will flow to
What is dilated cardiomyopathy?
Dilation in the heart walls with impaired contractibility
What are some complications of dilated cardiomyopathy?
Ventricular/atrial arrhythmias, sudden death, heart failure, impaired systolic and diastolic function
What mutated genes are associated with dilated cardiomyopathy?
Mutations in genes encoding cardiac cytoskeletal proteins eg titin, lamin, phospholamban etc
How is cardiac myopathy managed?
ACE inhibitors, beta blockers, diuretics for fluid overload, anticoagluation meds for atrial fibrillation, cardiac devices eg internal defribillator
