In a cardiac double stent having an outer netting over an inner scaffolding, a limiting ridge for defining advancement of the outer netting over the inner scaffolding, and locking clips integrated in the outer netting for engaging the scaffolding at the insertion limit, assures definite placement and avoids shifting or movement from retracting of the delivery device. The delivery device further includes restricting ridges limiting advancement of the inner netting to overlie the inner scaffolding a substantially equal portion on the proximate and distal ends of a guide wire such that balloon catheter expands first at the overlying portion outside the inner scaffolding to sealably contact the lumen wall on each side of the scaffolding to prevent contamination.