Cardiac Path I Flashcards
What changes are found in the myocardium and chambers of an aging heart?
Decreased LV size
Increase epcardial fat
lipofuscin and basophilic degeneration
Fewer myocytes,increased collagenfibers - reduced contractility and compliance
What changes are found in the valves of an aging heart?
Aortic and mitral valve annular calcification - stenosis
Fibrous thickening
Mitral valve degeneration - MVP -> increase LA size
Lambl excrescences - bumps
What changes are found in the vasculature of an aging heart?
Coronary atherosclerosis
Stiffening aorta - loss of elastic tissue
When does CHF occur? How many people are effected?
Occurs when the heart is unable to pump blood at a rate to meet peripheral demand, or can only do so with increased filling pressure
2% of US population
When the body is not getting the oxygen demand, what does the heart initially do to compensate?
Frank-starling mechanism
Myocardial hypertrophy
Activation on neurohumoral systems
When do cardiac myocytes become hypertrophic?
When there is sustained pressure or volume overload
or
Sustained trophic signals - b-adrenergic
What happens to myocytes in the setting of pressure overload?
Myocytes become thicker, LV wall thickness increases
What happens to myocytes in the setting of volume overload?
Myocytes elongate, and ventricular dilation is seen
Why is the hypertrophied heart vulnerable to ischemia-related decompensation?
because the hypertrophy of myocytes isnt accompanied by a matching increase in blood supply
What is the best measurement of hypertophied heart?
weight, not size or length
What is cardiac dysfunction characterized by?
Heart failure (systolic/diastolic)
Arrhythmias
Neurohumoral stimulation
What are the causes of LEFT sided HF?
Myocardial ischemia
HTN
Left-sided valve disease
Primary myocardial disease
What are the symptoms of LEFT sided HF?
Hypertension
Pulmonary congestion/edema/HTN
Atrial fib, stasis, thrombus if LV dysfunction->LA dilation
Reduced renal perfusion - prerenal azotemia
Hypoxic encephalopathy due to reduced CNS perfusion
What is the most common cause of RIGHT sided HF?
left-sided failure
What causes isolated RIGHT sided HF?
From any cause of pulmonary HTN
- lung disease
- Primary pulmonary HTN
- Pulmonary vasoconstriction
In primary RIGHT - sided HF, what will manifest
Pulmonary congestion is minimal Venous system is markedly congested - nutmeg liver/hepatomegaly - Splenomegaly - Effusions - Edema - Renal congestion
What can ischemia of the heart result in
Myocardial infarction
Angina pectoris
Chronic ischemic heart disease, with HF
SCD - arrhythmias
What are more than 90% of IHD secondary to?
atherosclerosis
causing chronic vascular occlusion, acute plaque changes leading to thrombus
What are some causes of IHD?
Atherosclerosis, increased myocardial demand, hypoxia due to anemia, lung disease, etc
What is Agnina pectoris?
Transient, often recurrent chest pain induced by myocardial ischemia insufficient to induce myocardial infarction