Krichenko angiographic classification of patent ductus arteriosus (illustration)

This diagram depicts the variations in PDA configuration based on the Krichenko angiographic classification:

• type A: conical ductus with prominent aortic ampulla and constriction near the pulmonary artery end
• type B: window-like (wide and very short) ductus
• type C: tubular ductus without constrictions
• type D: complex ductus with multiple constrictions
• type E: elongated ductus with constriction remote from the anterior edge of the trachea (when viewed on lateral angiography)