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Prostacyclin (prostaglandin I) is commonly considered the most effective treatment for PAH. Epoprostenol (synthetic prostacyclin) is given via continuous infusion that requires a semi-permanent central venous catheter. This delivery system can cause sepsis and thrombosis. Prostacyclin is unstable, and therefore has to be kept on ice during administration. Since it has a half-life of 3 to 5 minutes, the infusion has to be continuous, and interruption can be fatal. Other prostanoids have therefore been developed. Treprostinil can be given intravenously or subcutaneously, but the subcutaneous form can be very painful. An increased risk of sepsis with intravenous Remodulin has been reported by the CDC. Iloprost is also used in Europe intravenously and has a longer half life. Iloprost was the only inhaled form of prostacyclin approved for use in the US and Europe, until the inhaled form of treprostinil was approved by the FDA in July 2009.
The dual (ET and ET) endothelin receptor antagonist bosentan was approved in 2001. Sitaxentan (Thelin) was approved for use in Canada, Australia, and the European Union, but not in the United States. In 2010, Pfizer withdrew Thelin worldwide because of fatal liver complications. A similar drug, ambrisentan is marketed as Letairis in the U.S. by Gilead Sciences.
In general, the treatment of PPH is derived from the treatment of pulmonary hypertension. The best treatment available is the combination of medical therapy and liver transplantation.
The ideal treatment for PPH management is that which can achieve pulmonary vasodilatation and smooth muscle relaxation without exacerbating systemic hypotension. Most of the therapies for PPH have been adapted from the primary pulmonary hypertension literature. Calcium channel blockers, b-blockers and nitrates have all been used – but the most potent and widely used aids are prostaglandin (and prostacyclin) analogs, phosphodiesterase inhibitors, nitric oxide and, most recently, endothelin receptor antagonists and agents capable of reversing the remodeling of pulmonary vasculature.
Inhaled nitric oxide vasodilates, decreasing pulmonary arterial pressure (PAP) and pulmonary vascular resistance (PVR) without affecting systemic artery pressure because it is rapidly inactivated by hemoglobin, and improves oxygenation by redistributing pulmonary blood flow to ventilated areas of lung. Inhaled nitric oxide has been used successfully to bridge patients through liver transplantation and the immediate perioperative period, but there are two significant drawbacks: it requires intubation and cannot be used for long periods of time due to methemoglobinemia.
Prostaglandin PGE1 (Alprostadil) binds G-protein linked cell surface receptors that activate adenylate cyclase to relax vascular smooth muscle. Prostacyclin – PGI2, an arachadonic acid derived lipid mediator (Epoprostenol, Flolan, Treprostenil) – is a vasodilator and, at the same time, the most potent inhibitor of platelet aggregation. More importantly, PGI2 (and not nitrous oxide) is also associated with an improvement in splanchnic perfusion and oxygenation. Epoprostenol and ilioprost (a more stable, longer acting variation) can and does successfully bridge for patients to transplant. Epoprostenol therapy can lower PAP by 29-46% and PVR by 21-71%., Ilioprost shows no evidence of generating tolerance, increases cardiac output and improves gas exchange while lowering PAP and PVR. A subset of patients does not respond to any therapy, likely having fixed vascular anatomic changes.
Phosphodiesterase inhibitors (PDE-i) have been employed with excellent results. It has been shown to reduce mean PAP by as much as 50%, though it prolongs bleeding time by inhibiting collagen-induced platelet aggregation. Another drug, Milrinone, a Type 3 PDE-i increases vascular smooth muscle adenosine-3,5-cyclic monophosphate concentrations to cause selective pulmonary vasodilation. Also, by causing the buildup of cAMP in the myocardium, Milrinone increases contractile force, heart rate and the extent of relaxation.
The newest generation in PPH pharmacy shows great promise. Bosentan is a nonspecific endothelin-receptor antagonist capable of neutralizing the most identifiable cirrhosis associated vasoconstrictor, safely and efficaciously improving oxygenation and PVR, especially in conjunction with sildenafil. Finally, where the high pressures and pulmonary tree irritations of PPH cause a medial thickening of the vessels (smooth muscle migration and hyperplasia), one can remove the cause –control the pressure, transplant the liver – yet those morphological changes persist, sometimes necessitating lung transplantation. Imatinib, designed to treat chronic myeloid leukemia, has been shown to reverse the pulmonary remodeling associated with PPH.
Standard medical treatment consists of anticoagulants (blood thinners), diuretics, and oxygen. Lifelong anticoagulation is recommended, even after PEA. Routine inferior vena cava filter placement is not recommended.
In patients with non-operable CTEPH or persistent/recurrent PH after PEA, there is evidence for benefit from pulmonary vasodilator drug treatment. The microvascular disease component in CTEPH has provided the rationale for off-label use of drugs approved for PAH. Currently, only riociguat (a stimulator of soluble guanylate cyclase) is approved for treatment of adults with inoperable CTEPH or persistent or recurrent CTEPH after surgical treatment. Other drug trials are ongoing in patients with inoperable CTEPH, with macitentan recently proving efficacy and safety in MERIT
Decision making for patients with CTEPH can be complex and needs to be managed by CTEPH teams in expert centres. CTEPH teams comprise cardiologists and pulmonologists with specialist PH training, radiologists, experienced PEA surgeons with a significant caseload of CTEPH patients per year and physicians with percutaneous interventional expertise. Currently, there are three recognised targeted treatment options available: pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA) and pulmonary vasodilator drug treatment for inoperable patients.
Specialist imaging using either magnetic resonance or invasive PA is necessary to determine risks and benefits of interventional treatment with PEA or BPA.
In those with underlying heart disease, effective control of congestive symptoms prevents pulmonary edema.
Dexamethasone is in widespread use for the prevention of high altitude pulmonary edema. Sildenafil is used as a preventive treatment for altitude-induced pulmonary edema and pulmonary hypertension, the mechanism of action is via phosphodiesterase inhibition which raises cGMP, resulting in pulmonary arterial vasodilation and inhibition of smooth muscle cell proliferation. While this effect has only recently been discovered, sildenafil is already becoming an accepted treatment for this condition, in particular in situations where the standard treatment of rapid descent has been delayed for some reason.
Acute cardiogenic pulmonary edema often responds rapidly to medical treatment. Positioning upright may relieve symptoms. Loop diuretics such as furosemide or bumetanide are administered, often together with morphine or diamorphine to reduce respiratory distress. Both diuretics and morphine may have vasodilator effects, but specific vasodilators may be used (particularly intravenous glyceryl trinitrate or ISDN) provided the blood pressure is adequate.
Continuous positive airway pressure and bilevel positive airway pressure (BIPAP/NIPPV) has been demonstrated to reduce the need of mechanical ventilation in people with severe cardiogenic pulmonary edema, and may reduce mortality.
It is possible for cardiogenic pulmonary edema to occur together with cardiogenic shock, in which the cardiac output is insufficient to sustain an adequate blood pressure. This can be treated with inotropic agents or by intra-aortic balloon pump, but this is regarded as temporary treatment while the underlying cause is addressed.
Treatment aims to increase the amount of oxygen in the blood and reverse any causes of hypoxia.
- oxygen therapy
- mechanical ventilation
- Nitrous Oxide (NO·) Inhalation
- Prostaglandins (intravenous)
The therapies available to manage PPHN include the high frequency ventilation, surfactant instillation, inhaled nitric oxide, and extracorporeal membrane oxygenation. These expensive and/or invasive modalities are unavailable in the developing countries where the frequency and mortality of PPHN is likely to be much higher due to higher incidence of asphyxia and sepsis. In developing countries, the medical facilities are usually supplied with outdated equipment that was initially donated. "For people in developing countries, basic medical supplies are luxuries that are simply not available or not affordable. Doctors and nurses must constantly make do - washing and reusing "disposable" gloves and syringes, or substituting inappropriate materials such as fishing line or sewing thread for suture- or patients must go without needed care. In many countries patients must bring their own supplies, even acquire their own medicines, before treatment can be given." The limitations made it necessary to search for cheaper therapies, assuring quick effectiveness and stabilization of the patient going through a very high-risk situation. The treatments are chosen on the basis of low cost, low-tech, wide availability, and safety in the hands of non-professionals. Therefore, oral sildenafil citrate, has been the alternative way of therapy. The cost comparison shows that sildenafil is lower in cost than iNO and more readily available. There is improvement in oxygenation when oral sildenifal is administered according to the studies found in the Official Journal of the American Academy of Pediatric. The positive research results for varies studies indicates that oral sildenifal is a feasible source to improve oxygenation and survival in critical ill infants with PPHN secondary to parenchymal lung disease in centers without access to high-frequency ventilation, iNO, or ECMO.
Treatments for primary pulmonary hypertension such as prostacyclins and endothelin receptor antagonists can be fatal in people with PVOD due to the development of severe pulmonary edema, and worsening symptoms after initiation of these medications may be a clue to the diagnosis of pulmonary veno occlusive disease.
The definitive therapy is lung transplantation, though transplant rejection is always a possibility, in this measures must be taken in terms of appropriate treatment and medication.
Following diagnosis, mean survival of patients with PPH is 15 months. The survival of those with cirrhosis is sharply curtailed by PPH but can be significantly extended by both medical therapy and liver transplantation, provided the patient remains eligible.
Eligibility for transplantation is generally related to mean pulmonary artery pressure (PAP). Given the fear that those PPH patients with high PAP will suffer right heart failure following the stress of post-transplant reperfusion or in the immediate perioperative period, patients are typically risk-stratified based on mean PAP. Indeed, the operation-related mortality rate is greater than 50% when pre-operative mean PAP values lie between 35 and 50 mm Hg; if mean PAP exceeds 40-45, transplantation is associated with a perioperative mortality of 70-80% (in those cases without preoperative medical therapy). Patients, then, are considered to have a high risk of perioperative death once their mean PAP exceeds 35 mm_Hg.
Survival is best inferred from published institutional experiences. At one institution, without treatment, 1-year survival was 46% and 5-year survival was 14%. With medical therapy, 1-year survival was 88% and 5-year survival was 55%. Survival at 5 years with medical therapy followed by liver transplantation was 67%. At another institution, of the 67 patients with PPH from 1652 total cirrhotics evaluated for transplant, half (34) were placed on the waiting list. Of these, 16 (48%) were transplanted at a time when 25% of all patients who underwent full evaluation received new livers, meaning the diagnosis of PPH made a patient twice as likely to be transplanted, once on the waiting list. Of those listed for transplant with PPH, 11 (33%) were eventually removed because of PPH, and 5 (15%) died on the waitlist. Of the 16 transplanted patients with PPH, 11 (69%) survived for more than a year after transplant, at a time when overall one-year survival in that center was 86.4%. The three year post-transplant survival for patients with PPH was 62.5% when it was 81.02% overall at this institution.
The standard and most important treatment is to descend to a lower altitude as quickly as possible, preferably by at least 1000 metres. Oxygen should also be given if possible. Symptoms tend to quickly improve with descent, but more severe symptoms may continue for several days. The standard drug treatments for which there is strong clinical evidence are dexamethasone and nifedipine. Phosphodiesterase inhibitors such as sildenafil and tadalafil are also effective but may worsen the headache of mountain sickness.
This has a good prognosis if it is reversible. Causes include polycythemia and hyperfibrinogenemia.
It is sometimes treated with surgery, which involves rerouting blood from the right atrium into the left atrium with a patch or use of the Warden procedure. However, interest is increasing in catheter-based interventional approaches, as well as medical therapy for less severe cases.
Individuals can benefit from a variety of physical therapy interventions. Persons with neurological/neuromuscular abnormalities may have breathing difficulties due to weak or paralyzed intercostal, abdominal and/or other muscles needed for ventilation. Some physical therapy interventions for this population include active assisted cough techniques, volume augmentation such as breath stacking, education about body position and ventilation patterns and movement strategies to facilitate breathing.
Along with the measure above, systemic immediate release opioids are beneficial in emergently reducing the symptom of shortness of breath due to both cancer and non cancer causes; long-acting/sustained-release opioids are also used to prevent/continue treatment of dyspnea in palliative setting. Pulmonary rehabilitation may alleviate symptoms in some people, such as those with COPD, but will not cure the underlying disease. There is a lack of evidence to recommend midazolam, nebulised opioids, the use of gas mixtures, or cognitive-behavioral therapy.
Many people with this condition have no symptoms. Treatment is aimed at the health problems causing the lung problem and the complications caused by the disorder.
Fast-acting drugs for RA include aspirin and corticosteroids, which alleviate pain and reduce inflammation. Slow-acting drugs termed disease modifying antirheumatic drugs (DMARDs), include gold, methotrexate and hydroxychloroquine (Plaquenil), which promote disease remission and prevent progressive joint destruction. In patients with less severe RA, pain relievers, anti-inflammatory drugs and physical rest are sufficient to improve quality of life. In patients with joint deformity, surgery is the only alternative for recovering articular function.
Prognosis is related to the underlying disorder and the type and severity of lung disease. In severe cases, lung transplantation can be considered. This is more common in cases of bronchiolitis obliterans, pulmonary fibrosis, or pulmonary hypertension. Most complications are not fatal, but does reduce life expectancy to an estimated 5 to 10 years.
In terms of treatment for renovascular hypertension surgical revascularization versus medical therapy for atherosclerosis, it is not clear if one option is better than the other according to a 2014 Cochrane review; balloon angioplasty did show a small improvement in blood pressure .
Surgery can include percutaneous surgical revascularization, and also nephrectomy or autotransplantation, and the individual may be given beta-adrenergic blockers. Early therapeutic intervention is important if ischemic nephropathy is to be prevented. Inpatient care is necessary for the management of hypertensive urgencies, quick intervention is required to prevent further damage to the kidneys.
The first advance in the treatment of pulmonary alveolar proteinosis came in November 1960, when Dr. Jose Ramirez-Rivera at the Veterans' Administration Hospital in Baltimore applied repeated "segmental flooding" as a means of physically removing the accumulated alveolar material.
The standard treatment for PAP is whole-lung lavage, in which the lung is filled with sterile fluid with subsequent removal of the fluid along with the abnormal surfactant material. This is generally effective at improving PAP symptoms, often for a prolonged period of time. Since the mouse discovery noted above, the use of GM-CSF injections has also been attempted, with variable success. Lung transplantation can be performed in refractory cases.
If the inciting defect in the heart is identified "before" it causes significant pulmonary hypertension, it can normally be repaired through surgery, preventing the disease. After pulmonary hypertension is sufficient to reverse the blood flow through the defect, however, the maladaptation is considered irreversible, and a heart–lung transplant or a lung transplant with repair of the heart is the only curative option.
Transplantation is the final therapeutic option and only for patients with poor prognosis and quality of life. Timing and appropriateness of transplantation remain difficult decisions. 5-year and 10-year survival ranges between 70% and 80%, 50% and 70%, 30% and 50%, respectively. Since the average life expectancy of patients after lung transplantation is as low as 30% at 5 years, patients with "reasonable functional status" related to Eisenmenger syndrome have "improved survival with conservative medical care" compared with transplantation.
Various medicines and therapies for pulmonary hypertension are under investigation for treatment of the symptoms.
In treating pulmonary insufficiency, it should be determined if pulmonary hypertension is causing the problem to therefore begin the most appropriate therapy as soon as possible (primary pulmonary hypertension or secondary pulmonary hypertension due to thromboembolism). Furthermore, pulmonary insufficiency is generally treated by addressing the underlying condition, in certain cases, the pulmonary valve may be surgically replaced.
As previously stated, management of HFpEF is primarily dependent on the treatment of symptoms and exacerbating conditions. Currently treatment with ACE inhibitors, calcium channel blockers, beta blockers, and angiotensin receptor blockers are employed but do not have a proven benefit in HFpEF patients. Additionally, use of Diuretics or other therapies that can alter loading conditions or blood pressure should be used with caution. It is not recommended that patients be treated with phosphodiesterase-5-inhibitors or digoxin.
Antimineralocorticoid is currently recommended for patients with HFpEF who show elevated brain natriuretic peptide levels. Spironolactone is the first member of this drug class and the most frequently employed. Care should be taken to monitor serum potassium levels as well as kidney function, specifically glomerular filtration rate during treatment.
Beta blockers play a rather obscure role in HFpEF treatment but appear to play a beneficial role in patient management. There is currently a deficit of clinical evidence to support a particular benefit for HFpEF patients, with most evidence resulting from HFpEF patients' inclusion in broader heart failure trials. However, some evidence suggests that vasodilating beta blockers, such as nebivolol, can provide a benefit for patients with heart failure regardless of ejection fraction. Additionally, because of the chronotropic perturbation and diminished LV filling seen in HFpEF the bradycardic effect of beta blockers may enable improved filling, reduced myocardial oxygen demand and lowered blood pressure. However, this effect also can contribute to diminished response to exercise demands and can result in an excessive reduction in heart rate.
ACE inhibitors do not appear to improve morbidity or mortality associated with HFpEF alone. However, they are important in the management of hypertension, a significant player in the pathophysiology of HFpEF.
Angiotensin II receptor blocker treatment shows an improvement in diastolic dysfunction and hypertension that is comparable to other anti-hypertensive medication.
First-line therapy for people with heart failure due to reduced systolic function should include angiotensin-converting enzyme (ACE) inhibitors (ACE-I) or angiotensin receptor blockers (ARBs) if the person develops a long term cough as a side effect of the ACE-I. Use of medicines from this class is associated with improved survival and quality of life in people with heart failure.
Beta-adrenergic blocking agents (beta blockers) also form part of the first line of treatment, adding to the improvement in symptoms and mortality provided by ACE-I/ARB. The mortality benefits of beta blockers in people with systolic dysfunction who also have atrial fibrillation (AF) is more limited than in those who do not have AF. If the ejection fraction is not diminished (HFpEF), the benefits of beta blockers are more modest; a decrease in mortality has been observed but reduction in hospital admission for uncontrolled symptoms has not been observed.
In people who are intolerant of ACE-I and ARBs or who have significant kidney dysfunction, the use of combined hydralazine and a long-acting nitrate, such as isosorbide dinitrate, is an effective alternate strategy. This regimen has been shown to reduce mortality in people with moderate heart failure. It is especially beneficial in African-Americans (AA). In AAs who are symptomatic, hydralazine and isosorbide dinitrate (H+I) can be added to ACE-I or ARBs.
In people with markedly reduced ejection fraction, the use of an aldosterone antagonist, in addition to beta blockers and ACE-I, can improve symptoms and reduce mortality.
Second-line medications for CHF do not confer a mortality benefit. Digoxin is one such medication. Its narrow therapeutic window, a high degree of toxicity, and the failure of multiple trials to show a mortality benefit have reduced its role in clinical practice. It is now used in only a small number of people with refractory symptoms, who are in atrial fibrillation and/or who have chronic low blood pressure.
Diuretics have been a mainstay of treatment for treatment of fluid accumulation, and include diuretics classes such as loop diuretics, thiazide-like diuretic, and potassium-sparing diuretic. Although widely used, evidence on their efficacy and safety is limited, with the exception of mineralocorticoid antagonists such as spironolactone. Mineralocorticoid antagonists in those under 75 years old appear to decrease the risk of death. A recent Cochrane review found that in small studies, the use of diuretics appeared to have improved mortality in individuals with heart failure. However, the extent to which these results can be extrapolated to a general population is unclear due to the small number of participants in the cited studies.
Anemia is an independent factor in mortality in people with chronic heart failure. The treatment of anemia significantly improves quality of life for those with heart failure, often with a reduction in severity of the NYHA classification, and also improves mortality rates. The latest European guidelines (2012) recommend screening for iron-deficient anemia and treating with parenteral iron if anemia is found.
The decision to anticoagulate people with HF, typically with left ventricular ejection fractions <35% is debated, but generally, people with coexisting atrial fibrillation, a prior embolic event, or conditions which increase the risk of an embolic event such as amyloidosis, left ventricular noncompaction, familial dilated cardiomyopathy, or a thromboembolic event in a first-degree relative.
Several classes of antihypertensive agents are recommended, with the choice depending on the cause of the hypertensive crisis, the severity of the elevation in blood pressure, and the usual blood pressure of the person before the hypertensive crisis. In most cases, the administration of intravenous sodium nitroprusside injection which has an almost immediate antihypertensive effect, is suitable (but in many cases not readily available). Besides, nitroprusside runs a risk of cyanide poisoning. Other intravenous agents like nitroglycerine, nicardipine, labetalol, fenoldopam or phentolamine can also be used, but all have a delayed onset of action (by several minutes) compared to sodium nitroprusside.
In addition, non-pharmacological treatment could be considered in cases of resistant malignant hypertension due to end stage kidney failure, such as surgical nephrectomy, laparoscopic nephrectomy, and renal artery embolization in cases of anesthesia risk.
It is also important that the blood pressure is lowered smoothly, not too abruptly. The initial goal in hypertensive emergencies is to reduce the pressure by no more than 25% (within minutes to 1 or 2 hours), and then toward a level of 160/100 mm Hg within a total of 2–6 hours. Excessive reduction in blood pressure can precipitate coronary, cerebral, or renal ischemia and, possibly, infarction.
The diagnosis of a hypertensive emergency is not based solely on an absolute level of blood pressure, but also on the typical blood pressure level of the patient before the hypertensive crisis occurs. Individuals with a history of chronic hypertension may not tolerate a "normal" blood pressure.
Despite increasing incidence of HFpEF effective inroads to therapeutics have been largely unsuccessful. Currently, recommendations for treatment are directed at symptom relief and co-morbid conditions. Frequently this involves administration of diuretics to relieve complications associated with volume overload, such as leg swelling and high blood pressure.
Commonly encountered conditions that must be treated for and have independent recommendations for standard of care include atrial fibrillation, coronary artery disease, hypertension, and hyperlipidemia. There are particular factors unique to HFpEF that must be accounted for with therapy. Unfortunately, currently available randomized clinical trials addressing the therapeutic adventure for these conditions in HFpEF present conflicting or limited evidence.
Specific aspects of therapeutics should be avoided in HFpEF to prevent the deterioration of the condition. Considerations that are generalizable to heart failure include avoidance of a fast heart rate, elevations in blood pressure, development of ischemia, and atrial fibrillation. More specific to HFpEF include avoidance of preload reduction. As patients display normal ejection fraction but reduced cardiac output they are especially sensitive to changes in preloading and may rapidly display signs of output failure. This means administration of diuretics and vasodilators must be monitored carefully.
HFrEF and HFpEF represent distinct entities in terms of development and effective therapeutic management. Specifically cardiac resynchronization, administration of beta blockers and angiotensin converting enzyme inhibitors are applied to good effect in HFrEF but are largely ineffective at reducing morbidity and mortality in HFpEF. Many of these therapies are effective in reducing the extent of cardiac dilation and increasing ejection fraction in HFrEF patients. It is unsurprising they fail to effect improvement in HFpEF patients, given their un-dilated phenotype and relative normal ejection fraction. Understanding and targeting mechanisms unique to HFpEF are thus essential to the development of therapeutics.
Randomized studies on HFpEF patients have shown that exercise improves left ventricular diastolic function, the heart's ability to relax, and is associated with improved aerobic exercise capacity. The benefit patients seem to derive from exercise does not seem to be a direct cardiac effect but rather is due to changes in peripheral vasculature and skeletal muscle, which show abnormalities in HFpEF patients.
Patients should be regularly assessed to determine progression of the condition, response to interventions, and need for alteration of therapy. Ability to perform daily tasks, hemodynamic status, kidney function, electrolyte balance, and serum natriuretic peptide levels are important parameters. Behavioral management is important in these patients and it is recommended that individuals with HFpEF avoid alcohol, smoking, and high sodium intake.
In TAPVC without obstruction, surgical redirection can be performed within the first month of life. The operation is performed under general anesthesia. The four pulmonary veins are reconnected to the left atrium, and any associated heart defects such as atrial septal defect, ventricular septal defect, patent foramen ovale, and/or patent ductus arteriosus are surgically closed. With obstruction, surgery should be undertaken emergently. PGE1 should be given because a patent ductus arteriosus allows oxygenated blood to go from the circulation of the right heart to the systemic circulation.