ORLANDO, Fla.—The American College of Cardiology Foundation/American Heart Association (ACCF/AHA) has published recommendations online in the Journal of the American College of Cardiology and Circulation to help guide and inform practitioners on pulmonary hypertension. The report was released in conjunction with the 58th annual ACC scientific sessions this week in Orlando, Fla.
Highlights from the 2009 Expert Consensus Document on Pulmonary Hypertension: A Report of the ACCF Task Force on Clinical Expert Consensus Documents include:
- Pulmonary arterial hypertension (PAH) is a syndrome resulting from restricted flow through the pulmonary arterial circulation, resulting in increased pulmonary vascular resistance (PVR) and ultimately in right heart failure. Multiple pathogenic pathways are responsible for modifying smooth muscle and endothelial cells and adventitia, along with the imbalance in the vasoconstrictor/vasodilator milieu.
- Idiopathic PAH (IPAH) is the most common type of PAH and is more common in women. Familial PAH often results from a mutation in the bone morphogenic protein receptor-2 and is inherited as an autosomal dominant disease with incomplete penetrance and genetic anticipation. PAH is also associated with congenital heart disease (CHD), connective tissue diseases, drugs and toxins, human immunodeficiency virus, portal hypertension, hemoglobinopathies and myeloproliferative disorders.
- The one-year mortality in PAH is about 15 percent on modern therapy. Predictors of a poor prognosis include advanced functional class, poor exercise capacity, high right atrial pressure, significant right ventricular (RV) dysfunction, RV failure, low cardiac index, elevated brain natriuretic peptide and the scleroderma spectrum of diseases.
- Patients at sufficient risk for the development of PAH that warrant periodic screening include those with a family history of IPAH, scleroderma spectrum of diseases and portal hypertension who are undergoing evaluation for liver transplantation. The most appropriate study to obtain in patients suspected of having PAH is an echocardiogram.
- The diagnosis of PAH requires confirmation with a complete right heart catheterization. Acute vasodilator testing should be performed in experienced centers on IPAH patients to screen eligibility for long-term calcium channel blocker (CCB) therapy. Exceptions include those with overt right heart failure or hemodynamic instability.
- Treatment measures include diet, exercise, vaccinations and avoidance of pregnancy. Warfarin anticoagulation is recommended in all patients with IPAH. Diuretics are used for symptomatic management of RV volume overload. Oxygen is recommended to maintain oxygen saturation less than 90 percent. Acute responders to vasodilator testing treated with CCB should be followed closely for both the safety and the efficacy of this therapy.
- Continuous intravenous epoprostenol improves exercise capacity, hemodynamics and survival in IPAH and is the preferred treatment option for the most critically ill patients. Treprostinil, a prostanoid, may be delivered via either continuous intravenous or subcutaneous infusion.
- The endothelin receptor antagonists are oral therapies that improve exercise capacity in PAH. Liver function tests must be monitored indefinitely on a monthly basis. Phosphodiesterase-5 inhibitors also improve exercise capacity and hemodynamics in PAH. Patients with poor prognostic indexes should be initiated on parenteral therapy.
- PAH patients must be closely followed by experienced physicians and nurse clinicians. In general, office visits should be more frequent for patients with advanced symptoms, right heart failure and advanced hemodynamics and those on parenteral or combination therapy. Most experts obtain an assessment of functional class and exercise capacity.
- Disorders that elevate left heart filling pressures, including systolic dysfunction, diastolic dysfunction, and valvular heart disease, can result in elevated pulmonary artery pressures. In rare instances, PAH-specific therapy may be considered if the underlying cause has been optimally treated, the PCW is normal or minimally elevated, and the transpulmonary gradient and PVR are significantly elevated.