You are managing a patient admitted with worsening heart failure symptoms. She has been diagnosed with idiopathic pulmonary arterial hypertension and receives continuous IV epoprostenol.
Which one of the following is true?
IV epoprostenol addresses the altered prostacylin pathway in pulmonary arterial hypertension. It is the only therapy in which mortality benefit has been demonstrated using a randomized controlled trial. It is indicated when patients are in WHO-FC III and are deteriorating or are in WHO-FC IV, and is often used in combination with other therapies. Specialist nursing input is required. The infusion should never be interrupted and pain/ redness around the line entry site suggests infection which requires immediate attention. Spironolactone is an important diuretic for those in overt right heart failure.
You are invited by your consultant to study data recorded from right heart catheterization.
Transpulmonary gradient (TPG) is given by mPAP – mPWP and is normally <12 mmHg. Pulmonary vascular resistance is given by TPG divided by CO. A PWP >15 mmHg indicates left atrial hypertension. A vasodilator challenge is performed with inhaled nitric oxide to identify the small subset of patients with pulmonary arterial hypertension who will benefit from long-term calcium-channel blockade. A portion of those with an initially positive response (dmPAP ≥10 mmHg to ≤40 mmHg with d/normal CO) will become refractory to vasodilator provocation (and therefore calcium-channel blockade) in the future.
Which one of the following factors would worry you about a patient with pulmonary arterial hypertension?
It is key to identify the sickest patients in order to prioritize treatments. The following are recommended features which can be used to prognosticate: clinical evidence of RV failure, rapidly progressive symptoms, six-minute walk distance <380 m, peak oxygen consumption <12 mL/min/kg, high/rising BNP levels, pericardial effusion or TAPSE <1.5 cm, RAP >10 mmHg, cardiac index <2.1 L/min/m2 .
Concerning the treatment of pulmonary hypertension:
Sildenafil, which was originally developed as an anti-anginal before being used for erectile dysfunction, can be harmful in patients with PH secondary to left heart disease. Prostanoids are available in subcutaneous and inhaled preparations. Since only a minority of patients with pulmonary arterial hypertension respond to a vasodilator challenge (not all of whom will maintain this response), relatively few are on calcium-channel blockade. Transplant is considered for eligible patients.
With respect to pulmonary hypertension patients with congenital heart disease:
Pulmonary hypertension is an important complication in congenital heart disease. At the most extreme end of the spectrum is Eisenmenger syndrome, defined by reversal of a left to right shunt due to the development of pulmonary hypertension. Venesection for patients with Eisenmenger syndrome is now avoided. A sinus venosus defect (and aberrant pulmonary venous drainage) should be considered in patients with a dilated right heart and PH but no other explanation. A transoesophageal echocardiogram can visualize the upper inter-atrial septum well. The development of PAH can make pregnancy hazardous, and the oral contraceptive pill can interact with bosentan. Therefore family planning is vital. The six-minute walk test has recognized limitations. Therefore a number of factors are looked at when trying to prognosticate.