UW pulm physio 2 Flashcards
Hereditary PAH is most often due to an …………………..
Inactivating mutation in BMPR2
Patients with BMPR2 mutation have presdisposition for (2) ……………….
dysfunctional epithelium and smooth muscle cell proliferation
What is thought activate disease process in pulmonary hypertension?
An insult as infection or drugs
Insults, that activate pulmonary hypertension leads to decreased ………… (2) an increased …………….. (2)
decr. vasodilative, antiproliferative mediators eg NO, prostacyclin;
incr. vasoconstrictive, proliferative mediators eg endothelin
Insults, that activate pulmonary hypertension leads to decreased ………… (2) an increased …………….. (2)
decr. vasodilative, antiproliferative mediators eg NO, prostacyclin;
incr. vasoconstrictive, proliferative mediators eg endothelin
What is end result that cause pulmonary hypertension?
Vasoconstriction with vascular smooth muscle proliferation, intimal thickening and fibrosis + incr. pulm. vasc. resist and progresive pulmonary hypertension
What complication results due to PAH and causes right axis deviation on ECG?
PH –> right ventricular hyperthrophy as compensation –> right axis deviation on ECG.
How can be detected pulmonary artery hypertension? (physical examination)
Loud pulmonic component of S2
How can be detected pulmonary artery hypertension? (physical examination)
Loud pulmonic component of S2
2 steps of hereditary PAH development?
Abnormal BMPR2 predisposes to excessive smooth muscle and endotheliai proliferation. Insult such infection of drugs then activate the disease process
What form s in the last stage of PAH pathogenesis in arteries?
Capillary tufts (pexiform lesions)
What form s in the last stage of PAH pathogenesis in arteries?
Capillary tufts (pexiform lesions)
What triggers remodeling in systemic sclerosis in arteries?
Increased proliferation of T cells with secretion of variety cytokines (eg TGF-beta) –> stimulate fibroblasts –> increased collagen and extracellular matrix proteins.
Also, endothelial dysfunction due to inc. endothelin and TXA2 versus NO and prostacyclin
What other changes apart PAH can cause systemic sclerosis in lungs?
Interstitial fibrosis –> PAH due to hypoxia-induced vasoconstriction
What disease in chest cavicty also manifest in systemic sclerosis and induce RHF?
Pericardial fibrosis –> impaired diastolic dysfunction of RV
What causes loud pulmonic component in PAH?
forceful pulmonic valve closure in the setting of high pulmonary arterial pressure
What can create accenuated impulse palpated at the left sternal border in PAH?
RV enlargement due to inc. load (ie concentric RV hypertrophy)
What can create accenuated impulse palpated at the left sternal border in PAH?
RV enlargement due to inc. load (ie concentric RV hypertrophy)
How is described accenuated impulse felt on left sternal border in PAH?
Left parasternal lift due to right ventricular heave
PAH relatively more often afftects what population?
young women
What causes fatigue and exertional dyspnea in PAH?
Decreased CO
Where happens congestion due to HF in lungs?
Pulmonary venous congestion
Where happens congestion due to HF in lungs?
Pulmonary venous congestion
Smooth muscle cell proliferation in pulmonary arteries leads to ………… (1)
medial hypertrophy
Collagen depositions in pulmonary arteries leads to ………… (2)
Intimal thickening and fibrosis
The remodeling in pulmonary arteries is less extensive in PH due to LH or due to primary PAH?
in LV induced PAH.
primary is due to genetic mutations
Congenital heart disease that causes …………..shunting (eg, ventricular septal defect, atrial septal defect) can lead to …… via an increase in pulmonary arterial blood flow
left-to-right;
pulmonary hypertension
Why occurs hypoxic vasoconstriction in pulmonary hypertension?
Hypoxic vasoconstriction is a physiologic mechanism unique to lung tissue that helps minimize ventilation-perfusion mismatch and increase overall gas exchange efficiency.
An area of ventilation defect without perfusion defect is suggestive of conditions that lead to …………………..
acute alveolar filling (pneumonia, pulmonary edema)
Pulmonary arterial compliance in pulmonary hypertension?
decreases due to vascular remodeeling and stiffening of the walls
The main mechanism of pulmonary hypertension in chronic hypoxic diseases?
hypoxia induced vasoconstriction
Massive PE can lead to sudden occlusion of …..% of the pulmonary arterial circulation
> 50proc
If CT is contraindicated for PE diagnostics, what method we would use?
V/Q scan
Low tidal volume ………… dead-space ventilation
increases
Increases in physiologic dead space occur in many lung diseases, including (3)
PE, emphysema, ARDS
lower tidal volumes increase the proportion of ………………..
each breath composed of dead space
minute ventilation formula?
tidal volume x RR
Why patients with weakened respiratory muscles tend to breath at low tidal volumes?
To minimize the work of breathing
Patients with weakened respiratory muscles tend to breath at low tidal volume. What is a compensatory response?
hypoventilation triggers increase in respiratory drive –> incr. RR to maintain ventilation
What is rapid shallow breathing index (RSBI)?
Ratio of respiratory rate/tidal volume
How is called the ratio of respiratory rate/tidal volume?
Rapid shallow breathing index (RSBI)
What indicates low RSBI? (3)
relatively high tidal volume, relatively efficient breathing and lower likelihood of recurrent respiratory failure once ventilatory support is discontinued.
What indicates low RSBI? (3)
relatively high tidal volume, relatively efficient breathing and lower likelihood of recurrent respiratory failure once ventilatory support is discontinued.
Increases in both respiratory rate and tidal volume result in increased ……………..
minute ventilation
A decrease in respiratory rate and an increase in tidal volume would ……………
keep minute ventilation
Decr. RR and inc. tidal volume. Dead space ventilation each breath?
decrease
Because at low tidal volumes a higher proportion of each breath is composed ……………, it leads to………………
Of dead space;
leads to an increase in wasted ventilation (inefficient breathing)
Because at low tidal volumes a higher proportion of each breath is composed ……………, it leads to………………
Of dead space;
leads to an increase in wasted ventilation (inefficient breathing)
How astma changes compliance of the lungs?
doesnt change
What method is used if patient cannot tolerate CT angiography in PE with IV contrast?
V/Q scan - compares regional ventilation and perfussion.
V/Q scan in PE. 1 stage - what is used?
Radiolabeled aerosol - inhaled and delivered throughout the tracheobronchial tree.
V/Q scan in PE. 2 stage - what is used?
IV tracer is distributed throughout the pulmonary vasculature.
V/Q scan in spontaneous pneumotorax?
normal perfusion but impaired ventilation due to compressed lung
what is normal thick of the RV wall?
3-4mm
Long-standing pulmonary hypertension eventually leads to ……………………………right ventricle (cor pulmonale)
hypertrophy and/or dilation of the right ventricle
What is the most common cause of death in PAH?
RHF with circulatory collapse and respiratory failure
What is the difference between dilated cardiomyopathy and cor pulmonale due to PAH?
dilated cardiomyopathy - all 4 chambers are dilated
RV hypertrophy due due PAH - thick RV wall
Gross changes in WPW?
none, because it is electrophysical abnormality.
Endothelin pathway and result?
Proendothelin –> endothelin-1 –> activates endothelin receptor on smooth mucle –> vasoconstriction+proliferation
NO pathway and result?
L-arginine –> forms NO and L-citruline –> NO converts GTP to cGMP –> vasodilation and decreased proliferation
Prostacyclin pathway and result?
Arachidonic acid –> prostacyclin –> cAMP –> vasodilation and decr. proliferation
What part of vessel proliferates in PAH?
Intima
What targets PAH therapy?
Targets the mediator imbalance created by endothelial dysfunction (inc. vasoconstrictive mediators and decr. vasodilative mediators)
What is endothelin receptor antagonist?
Bosentan
What is prostacyclin analogue?
Epoprostenol
NO oxide enhancing agent?
Sildenafil
What is the same effect of all medications used for PAH therapy?
All help to reduce tissue proliferation regardless their mechanism of action
