Cardio II Flashcards
(21 cards)
Aneurysms
localized dilations due to weaknesses in vessel wall
as radius of dilation increases, wall tension and the chance of rupture increases
Aneurysm causes:
congenital defects, trauma, infections, or atherosclerosis
Berry aneurysm
spherical dilation of a vessel at a bifurcation
Fusiform aneurysm
involves entire circumference of a vessel
Saccular aneurysm
extends over part of the circumference of a vessel
Varicose veins
permanent dilation and tortuosity of veins, most commonly seen in the legs, usually a result of valve insufficiency
Venous thrombosis
thrombus (clot) in a vein
DVT occurs in the lower extremities- can lead to pulmonary embolism
DVT
DVT occurs in the lower extremities- can lead to pulmonary embolism
most common sites are soleus sinuses, posterior tibial veins, and peroneal veins
manifestations: calf pain and tenderness
DVT treatment
prevention- exercise, support stocking, compression devices, prophylactic anti-coagulants (heparin, warfarin)
thrombolytic therapy- streptokinase, urokinase, tissue plasminogen activator
surgical removal of thrombus- filters to prevent emboli
Blood pressure
BP= CO x peripheral resistance
Systolic BP
depends on amount and rate of blood ejected into the aorta and on aortic compliance
aorta becomes less elastic in older individuals and systolic BP increases
Diastolic BP
depends on elasticity of aorta, competency of aortic valve, and peripheral resistance
resistance increases in response to atherosclerosis or vasoconstriction
Pulse pressure (PP)
difference between systolic and diastolic
Mean arterial blood pressure (MAP)
average BP in the systemic circulation and indicator of tissue perfusion
MAP= diastolic + 1/3 pulse pressure
Regulation of BP: neural mechanisms
cardiovascular center in medulla- primarily responsive to baroreceptors in the aorta and carotid arch
Regulation of BP: neural mechanisms (parasympathetic)
parasympathetic outflow via vagus nerve (slowing the heart)
Regulation of BP: neural mechanisms (sympathetic)
sympathetic outflow via spinal sympathetic nerves
–increases rate and force of cardiac contraction and causes peripheral vasoconstriction)
Regulaton of BP: Humoral mechanisms (Renin-Angiotensin system)
renin released in response to low BP or increased sympathetic activity increases angiotensin II (AII)
AII increases aldosterone (salt and water retention) and vasoconstriction
Regulation of BP: humoral mechanisms (Vasopressin)
vasopressin (anti diuretic hormone)
increases BP by increasing water reabsorption in the kidney
Hypertension: major risk factor for..
atherosclerosis
left ventricular hypertrophy
strokes and TIAs
nephropathies
Orthostatic hypotension
abnormal drop in blood pressure on assumption of a standing position
baroreceptors sense decreased pressure and initiate reflex constriction of the vein and arterioles and an increase in HR
