ICU · Respiratory / ventilation

Pulmonary Hypertension & Cor Pulmonale

Also known as Pulmonary hypertension · PH · Cor pulmonale · Right ventricular failure · Acute cor pulmonale · Pulmonary arterial hypertension · PAH · WHO groups · CTEPH · Vasopressin for RV failure

Pulmonary hypertension (a mean pulmonary artery pressure above 20 mmHg) is classified into five WHO groups: pulmonary arterial hypertension (group 1), left heart disease (2), lung disease and hypoxia (3), chronic thromboembolic (4), and multifactorial (5). Cor pulmonale is the right-ventricular hypertrophy, dilation, and failure from the pulmonary hypertension, classically from lung disease (group 3). The thin-walled right ventricle tolerates volume but not pressure: a rising pulmonary vascular resistance causes it to dilate and fail, the septum bows into the left ventricle (the D-shaped septum), the left-sided output falls, and tricuspid regurgitation worsens. The ICU management optimises the preload (diurese, do not overfill), reduces the afterload (inhaled nitric oxide, prostacyclin, PDE5 inhibitors), supports the contractility (milrinone, dobutamine), and maintains the systemic blood pressure to preserve the RV coronary perfusion — vasopressin is preferred, as it raises the systemic vascular resistance without raising the pulmonary.