Term
| what is the definition for pulmonary HTN? (*know this*) |
|
Definition
| an abnormal hemodynamic state in which the *pulmonary artery pressure and the *pulmonary vascular resistance are elevated, resulting in R ventricular failure and early death. or PA mean pressure >25 mm Hg @ rest and >30 mm Hg w/exertion |
|
|
Term
| how common is true idiopathic PAH (pulmonary arterial HTN)? who does it affect most commonly? |
|
Definition
| pretty rare (2-3 per million), and it usually affects young women |
|
|
Term
| how common is pulmonary HTN among pts with connective tissue disease? |
|
Definition
| more common: more than half of pts w/scleroderma, 21% of pts w/ RA and up to 14% of pts w/SLE |
|
|
Term
| what are other disorders where pts may be affected by pulmonary HTN? |
|
Definition
| pulmonary veno-occlusive disease, portal HTN, sickle-cell disease (up to 40%), pulmonary embolism, and COPD (50% of pts w/severe COPD) |
|
|
Term
| how does pulmonary HTN develop? |
|
Definition
| 1) inflammation of the vessels in pulmonary circulation narrows their caliber - which puts a backstrain on the R ventricle. 2) blockage in the pulmonary veins backs up to the R side of the heart 3) outflow tract blockage such as mitral stenosis. |
|
|
Term
| how does pulmonary HTN cause tricuspid regurgitation? |
|
Definition
| the R side of the heart dilates and the valves can no longer approximate |
|
|
Term
| what are the 6 Dana Point classifications for pulmonary HTN? |
|
Definition
|
|
Term
| what typifies group 1 and 1' of the dana point classification? |
|
Definition
| primary problem is in the vasculature itself, 1: idiopathic PAH, inherited, drug/toxin induced, connective tissue disease, HIV, portal HTN, congenital heart disease, schistosomiasis, chronic hemolytic anemia, persistent pulm HTN of the newborn, and 1':pulmonary veno-occlusive disease and pulm capillary hemangiomatosis |
|
|
Term
| what typifies group 2 of the dana point classification? |
|
Definition
| pulmonary HTN due to *L heart disease*: systolic dysfunction, diastolic dysfunction and valvular disease |
|
|
Term
| what typifies group 3 of the dana point classification? |
|
Definition
| pulmonary HTN due to *lung disease/hypoxemia*: COPD, interstitial lung disease, mixed restrictive/obstructive patterns, sleep-disordered breathing, alveolar hypoventilation disorders, chronic exposure to high altitute, and developmental abnormalities |
|
|
Term
| what typifies group 4 of the dana point classification? |
|
Definition
| pts w/chronic thromboembolic pulmonary HTN |
|
|
Term
| what typifies group 5 of the dana point classification? |
|
Definition
| misc: hematologic disorders (myeloproliferative, splenectomy), systemic disorders (sarcoidosis, langerhans cell histiocytosis), metabolic disorders (glycogen storage disease, gaucher, thyroid disorders), and others (tumoral obstruction, fibrosing mediastinitis, chronic renal failure on dialysis) |
|
|
Term
| what is the pathophysiology of pulmonary HTN? |
|
Definition
| imbalance between vasoconstrictors/vasodilators, smooth muscle/endothelial cell proliferation, and in situ thrombosis |
|
|
Term
| what vasoconstrictors is there an increase in? |
|
Definition
| endothelin-1 (important - drugs target this in tx), thromboxane A2, serotonin |
|
|
Term
| what vasodilators is there an increase in? |
|
Definition
| prostacyclin (target of rx therapy), NO (target of rx therapy), vasoactive peptide |
|
|
Term
| how is smooth muscle/endothelial cell proliferation promoted? |
|
Definition
| *increased VEGF, endothelin-1, serotonin and *decreased prostacyclin, NO, vasoactive peptide promote SMC/endothelial cell proliferation as well as mutations in bone morphogenic protein receptor 2 (BMPR2), which is a gene involved in proliferation+apoptosis |
|
|
Term
| what promotes in situ thrombosis? |
|
Definition
| *increased thromboxane A2, serotonin, and plasminogen activator inhibitor-1 and *decreased prostacyclin, NO, vasoactive peptide, and tissue plasminogen activator |
|
|
Term
| what are the *most important* mediators of pulm HTN? |
|
Definition
| prostacyclin (vasodilator, antiproliferative, antiplatelet), endothelin 1 (vasoconstrictor, proproliferative mediator), and NO (vasodilator, platelet inhibitor, inhibits smooth muscle proliferation) |
|
|
Term
| what is the hallmark lesion of pulm HTN? what causes it? how does it appear? |
|
Definition
| the plexiform lesion, which develops at branch points as a result of shear stress leading to transmural destruction which is repaired by granulation tissue = resulting in the plexiform lesion. it appears as an elastic tissue stain, showing loss of one or both layers (onion peeling) |
|
|
Term
| what characterizes the clinical presentation of pts w/pulm HTN? |
|
Definition
| dyspnea (95%), exertional *syncope (hypoxia/decreased CO), exertional chest pain (R ventricular ischemia), hemoptysis (due to microvascular aneurysms rupturing under high pressure), signs/symptoms of R-sided CHF (peripheral edema/RUQ fullness/abdominal distention) |
|
|
Term
| what findings on a physical exam would indicate possible pulm HTN? |
|
Definition
| *prominent p2, R-sided s4, *pulm artery "tap+flow" murmur, graham steel murmur of PR (diastolic), tricuspid regurg murmur, R ventricular heave, and digital clubbing. if R ventricular failure is present: increased JVP, hepatomegaly, peripheral edema, and ascites |
|
|
Term
| what diagnostic studies would you order for a pt suspected of pulm HTN? |
|
Definition
| CXR, EKG, echocardiogram, pulm function tests/ABG, CT chest, V/Q scan, sleep oximetry/nocturnal polysomnogram, cardiac catheterization, ANA/HIV/LFTs/TFTs/CBC, and 6 min walk test |
|
|
Term
| what is seen on a CXR in a pt w/pulm HTN? |
|
Definition
| dilatation/pruning of pulmonary arteries (prominent hila) and enlargement of the R atrium and ventricle |
|
|
Term
| what is seen on an EKG that is indicative of pulm HTN? |
|
Definition
| R axis deviation, RBBB, R atrial enlargement, and RVH - meaning: L axis deviation, large R wave in V1, notching of the QRS complex, prominent P wave |
|
|
Term
| what is seen on an echocardiogram that is indicative of pulm HTN? |
|
Definition
| increased R ventricular systolic pressure, flattening of the septum, tricuspid regurg, pulmonic regurg |
|
|
Term
| what is the purpose of PFTa/ABGs in working up a possible pulm HTN pt? |
|
Definition
| determining if there is severe obstruction/restriction, if there is severe diffusion abnormality, or if there is hypoxemia/hypercapnea/acidosis |
|
|
Term
| what would you see on a CT scan in a pt suspected of pulm HTN? |
|
Definition
| an enlarged pulmonary trunk and peripheral pruning of the pulmonary peripheral vasculature. pulm emboli are also available |
|
|
Term
| when might you order a V/Q scan for a suspected pulm HTN pt? |
|
Definition
| if you think the pt has chronic thromboembolic disease or an unresolved pulmonary embolus as a cause |
|
|
Term
| what is the definitive study in assessment of chronic thromboembolic disease? |
|
Definition
| a pulmonary arteriogram - will help confirm results of V/Q scan |
|
|
Term
| what does a nocturnal polysomnogram look for? |
|
Definition
| abnormalities in oxygen desaturation/apneas during sleep that may be contributing to pulmonary HTN |
|
|
Term
| what does cardiac (swan gantz) catheterization tell you about possible pulm HTN pts? |
|
Definition
| whether there are increased pulmonary artery pressures if there is increased pulmonary vascular resistance, and what the pulm capillary wedge pressure is (this can help you determine if pulm venous backup is the cause of the HTN, if less than 15 mm HG, it isn't pulm venous backup). the swan gantz catheter is also helpful in assessing drug therapy success in lowering pulm artery pressure |
|
|
Term
| what is the 6 min walk test? what is its purpose? |
|
Definition
| a pt is asked to walk for 6 min on a flat surface at their own pace, and the number of meters is recorded. this measures their ability to perform the activities of daily living, evaluates functional status, monitors therapy, and assesses prognosis in pts w/cardiopulmonary disease |
|
|
Term
| what needs to be done after a pulm HTN dx is made? |
|
Definition
| clinically classify the pulm HTN (dana point), further work-ups in addition to dx are often needed and once the work-up is complete - place the pt into one of six clinical classification categories |
|
|
Term
| what are the principles for pulm HTN tx? |
|
Definition
| 1)prevent and reverse the vasoactive substance imbalance as well as vascular remodeling 2) prevent RV failure by: decreasing wall stress (decrease PVR, PAP, RV diameter) and ensuring adequate systemic diastolic BP 3) treat and manage reversible and underlying causes of pulm HTN |
|
|
Term
| how are group 1+1' of the dana point classification system treated? |
|
Definition
| group 1 and 1' are treated with: prostanoids, endothelin receptor anatagonists, phosphodiesterase-5 inhibitors, and Ca++ channel blockers |
|
|
Term
| how is group 2 of the dana point classification system treated? |
|
Definition
| primary therapy: treat underlying heart condition |
|
|
Term
| how is group 2 of the dana point classification system treated? |
|
Definition
| treat the underlying cause of hypoxemia and utilize supplemental O2 |
|
|
Term
| how is group 4 of the dana point classification system treated? |
|
Definition
| anticoagulation and surgical thromboendarterectomy |
|
|
Term
| how is group 5 of the dana point classification system treated? |
|
Definition
| due to multifactorial nature, primary therapy is directed at underlying causes |
|
|
Term
| how does O2 help with pts in group 1+1' of the dana point classification system? |
|
Definition
| oxygen reduces vasoconstriction |
|
|
Term
| how do diuretics help with pts in group 1+1' of the dana point classification system? what caution needs to be taken with this method? |
|
Definition
| diuretics will decrease RV wall stress and relieve RHF symptoms. diuresis must be administered gently as the dilated RV is preload dependent |
|
|
Term
| how does digoxin help with pts in group 1+1' of the dana point classification system? |
|
Definition
| atrial fibrillation control and counteracting the negative ionotropic effects of Ca++ channel blockers |
|
|
Term
| how do dubutamine/inhaled NO help with pts in group 1+1' of the dana point classification system? |
|
Definition
| these can help with decompensated pulm HTN |
|
|
Term
| when does anticoagulation therapy help with pts in group 1+1' of the dana point classification system? |
|
Definition
| this is indicated in the setting of VTE and decreases the risk of VTE w/R heart failure (questionable benefit in the prevention of microthrombi/decreased mortality) |
|
|
Term
| how do Ca++ channel blockers help with pts in group 1+1' of the dana point classification system? |
|
Definition
| Ca++ channel blockers (nifedipine/diltiazem) should only be used if pts have a positive acute vasoreactivity test and only 1/2 will be long term responders - but pts will have decreased mortality. ADRs: hypotension, lower limb edema |
|
|
Term
| what is the acute vasoreactivity test? |
|
Definition
| the pt inhales NO/adenosine/prostacyclin to ID if they are more likely to have a long-term response to oral CCBs. a positive test is defined as decreased pulm arterial pressure of a >10 mm Hg to <40 w/an increase or stable cardiac output. generally ~10% are acute responders, and if pts have no response they are still candidates for other vasodilators |
|
|
Term
| if a pt has a negative acute vasoreactivity test, and is thus ineligble for CCBs, what are other vasodilators that can be used? |
|
Definition
| prostacyclin, prostacyclin analogs, endothelin-1 antagonists, and PDE-5 inhibitors |
|
|
Term
| how does IV prostacyclin (epoprostenol) help with pts in group 1+1' of the dana point classification system? ADRs? |
|
Definition
| IV prostacyclin increases vasodilation, decreases platelet aggregation/SMC proliferation and benefits w/increase w/time (possibly due to vascular remodeling). IV prostacyclin also leads to improved 6 min walk test, decreased PVR (50%), decreased pulm arterial pressure, and a decrease in mortality. ADRs: HA, flushing, jaw/leg pain, abdominal cramps, nausea, diarrhea, infection, central venous catheter dysfunction (pts have to walk around with an IV pump) |
|
|
Term
| how do prostacyclin analogs (iloprost, treprostinil, beraprost) help with pts in group 1+1' of the dana point classification system? how do these drugs differ? |
|
Definition
| prostacyclin analogs have the same MOA as IV, but are inhaled or SC. *iloprost (inhaled) will decrease symptoms, improve the 6 min walk test, decrease PVR (25%), decrease PAP (5 mm Hg), tend to decrease clinical events, and require 6-12 inhalations daily. *treprostinil (SC) will will decrease symptoms, improve the 6 min walk test, decrease PVR (10%), decrease PAP (3 mm Hg), tend to decrease clinical events, and is given via SC microcatheter (infusion site rxns are common). *beraprost is PO and has no sustained change in 6 min walk test/PAP/PVR/clinical events |
|
|
Term
| how do endothelin-1 antagonists (bosentan+ambrisentan) help with pts in group 1+1' of the dana point classification system? ADRs? |
|
Definition
| *bosentan decreases SMC remodeling, increases vasodilation, decreases fibrosis, decreases symptoms, improves the 6 min walk test, decreasess PVR (25%), decrease PAP (2 mm Hg), and decreases clinical events. *ambrisentan (selective type A endothelin-1 receptor) is administered PO and is shown to improve exercise tolerance, hemodynamics, and quality of life. ADRs: *increased LFTs (*hepatoxicity*), headache, anemia, and edema |
|
|
Term
| how do PDE-5 inhibitors help with pts in group 1+1' of the dana point classification system? ADRs? |
|
Definition
| PDE-5 (phosophodiesterase-5) inhibitors such as sildenafil (viagra) increase cGMP (leading to increased NO -> vasodilation), decrease SMC proliferation, decrease symptoms, improve the 6 min walk test, decrease PVR (28%), decrease PAP (5 mm Hg), no change in clinical events, and improved arterial oxygenation (only w/sildenafil). ADRs: headache, vision changes, and sinus congestion |
|
|
Term
| what are possibilities if pts are refractory to pulm HTN rx tx? |
|
Definition
| balloon arterial septostomy (create a R->L shunt causing increased CO, decreased SaO2, & net increase in tissue O2 delivery) or lung transplant (uni-/bi-, used in IPAH, and heart/lung may be needed) |
|
|
Term
| what are the NYHA functional classes for pulm HTN? |
|
Definition
| class 1 (asymptomatic), class 2 (symptomatic w/ordinary physical activity), class 3 (symptomatic w/less than ordinary effort), class 4 (symptomatic at rest) |
|
|
Term
| who of the NYHA functional classes gets tx? |
|
Definition
| class 1: nobody - just monitoring, class 2+3: check vasoreactivity, administer drugs if appropriate, class 4: IV prostanoids |
|
|
Term
| what is the prognosis for pts in group 1+1' of the dana point classification system? |
|
Definition
| ~66% 2 yr survival, ~48% 5 yr survival. increased brain natriuretic peptide: increased mortality |
|
|
