Investigation of the Ringer Perfusion Balloon Catheter (Ringer PTCA)

Inclusion Criteria: * Male and Female subjects \>18 years old. * Patients undergoing clinically indicated non-emergent PCI as a stand-alone procedure or in combination with diagnostic angiography during the same procedure. * Study target lesion characteristics: a) native de-novo coronary stenosis of at least 70% visually estimated stenosis, or at least 50% visually estimated stenosis and shown to be physiologically significant by flow-mediated criteria (FFR \<0.80, IFR \<0.91); b) estimated reference vessel diameter 2.0-4.5mm; c) lesion length \<25mm; d) calcification not greater than mild. * Per investigator assessment, the patient may benefit from inflation distal perfusion during balloon inflation. Examples include, but are not limited to: (i) LV systolic dysfunction with LVEF\<50% by any modality; (ii) a territory subtended by the target vessel downstream from the target lesion that is estimated to be in excess of 25% of viable LV mass; (iii) prior hemodynamic or electrical instablility during intervention on the target lesion; (iv) the potential to avoid placement of a coronary stent if a stent-like result can be achieved through prolonged balloon inflation. * Female subjects of childbearing potential must have a negative pregnancy test per standard of care for PCI and be practicing contraception. * Informed consent provided. Exclusion Criteria: * Hemodynamic or arrhythmic instability within 48 hours or a myocardial infarction within 72 hours of PCI. * More than 2 lesions planned during index PCI. * Procedural complication developing prior to PCI of study target. * Ejection fraction (EF) \<25%. * Creatinine clearance (Cr-Cl) \<25 mg/dL. * Baseline flow at study target \<TIMI-2.