NPPB and pulmonary arterial hypertension: Other causes of increased NT-proBNP levels include left ventricular systemic dysfunction (6), acute coronary syndromes (7–9), percutaneous coronary interventions (10), cardiac surgery (11), heart transplantation (12), left ventricular hypertrophy (13), right ventricular dysfunction secondary to pulmonary diseases (pulmonary embolism, pulmonary hypertension, chronic lung disease and respiratory failure) (14, 15), valvular heart disease (especially mitral and aortic) (16, 17), certain cardiac inflammatory (18) or infectious diseases (19), endocrinology diseases (20) and high output states (21).