Volume-overloaded Patients

For patients who are volume overloaded at presentation, diuresis—even against the background of marginal cardiac output and low blood pressure—may be required [27].

In a subset of patients, support with inotropes or pressors is necessary: animal data suggest a better haemodynamic response with sympathomimetic agents such as dobutamine, noradrenaline, and dopamine rather than vasopressin or phenylephrine; milrinone also has favourable effects on cardiac output but may lead to excessive hypotension [14-17].

Diuretics are indicated for right ventricular volume overload [1]. However, rapid and excessive diuresis may precipitate systemic hypotension and renal insufficiency [1]. Spironolactone, an aldosterone antagonist that is of benefit in patients with left-heart failure, is also used to treat right-heart failure [1]. Although not extensively studied in PAH, digitalis is sometimes used for refractory right ventricular failure [1,12]. In addition, atrial flutter or other atrial dysrthythmias often complicate late-stage right-heart dysfunction, and digoxin may be useful for rate control [1].