- Clinically significant heart disease defined as a myocardial infarction documented by an ST elevation (STEMI) on electrocardiogram (ECG) within 6 months prior to screening, percutaneous coronary intervention or coronary artery bypass surgery within 6 months prior to screening, unstable angina pectoris, congestive heart failure (NYHA class III/IV or known left ventricular ejection fraction < 25%), ischaemic heart disease, right heart failure, significant right ventricular hypertrophy, or uncontrolled arrhythmia.