Treatment of Drug-eluting Stent (DES) In-Stent Restenosis With SeQuent® Please Paclitaxel Eluting Percutaneous Transluminal Coronary Angioplasty (PTCA) Catheter

Inclusion Criteria: Patient Related * Patients with stable angina pectoris (CCS class 1-3) or with unstable angina pectoris (Braunwald class 1-2, A-C) or documented ischemia or with documented silent ischemia * Patients eligible for coronary revascularization by means of PCI * Patients suitable for coronary revascularization of any sort (balloon angioplasty, device-assisted balloon-angioplasty, or coronary artery bypass grafting) * Patients must be ≥ 18 years of age * Women of childbearing potential may not be pregnant nor have the desire to becoming pregnant during the first year following the study procedure. Hence, patients will be advised to use an adequate birth control method up to and including 6 months follow-up * Patients who are mentally and linguistically able to understand the aim of the study and to show sufficient compliance in following the study protocol * Patients must agree to undergo the 6 months angiographic follow-up * Patients must agree to undergo the 1 and 3 year clinical follow-up * Patient is able to verbally acknowledge an understanding of the associated risks, benefits, and treatment alternatives to therapeutic options of this trial, e.g., balloon angioplasty by means of the paclitaxel-eluting PTCA-balloon catheter or other suitable devices. The patients, by providing their informed consent, agree to these risks and benefits as stated in the patient informed consent document. Inclusion Criteria: Lesion Related * In-stent restenosis or Mehran type III stenoses reaching ≤ 2 mm into the adjacent native vessel of a drug eluting stent (DES), in a native coronary artery (reference vessel between ≥ 2.5 and ≤ 3.5 mm, lesion length ≤ 22 mm as angiographically documented) * Diameter stenosis pre procedure must be either ≥ 70 % or ≥ 50 % if ischemia corresponding to the target lesion is documented either by exercise stress ECG, stress echocardiography, scintigraphy, MRT, or suspected based on angina pectoris. * DES in-stent restenosis independent of the the number of metal layers (e.g. restenosed DES following BMS and/or DES implantation(s)) Exclusion Criteria: Patient Related * Patients with acute (\< 24 h) or recent (48 hours) myocardial infarction * Patients with unstable angina pectoris (Braunwald class 3) * Patients with severe congestive heart failure * Patients with severe heart failure NYHA IV * Patients demonstrating clinical signs of cardiogenic shock at the time of the procedure (systolic blood pressure of less than 80 mmHg requiring inotropic support, IABP and/or fluid challenge) * Patients with severe valvular heart disease * Women who are pregnant or lactating patients with life expectancy of less than five years or factors making clinical follow-up difficult * Patients with another coronary stent previously implanted into the target vessel * Patients with bleeding diathesis in whom anticoagulation or anti-platelet medication is contraindicated * Patients who had a cerebral stroke \< 6 months prior to the procedure * Patient participates in other clinical trials involving any investigational device or drug * Untreated hyperthyroidism * Patient has presence or history of severe renal failure (GFR \< 30ml/min) and is therefore not eligible for angiography. Patient's serum creatinine levels must be documented. * Post transplantation of any organ or immune suppressive medication * Other disease to jeopardize follow-up (e.g. malignoma) * Addiction to any drug or to alcohol * Patients with any type of surgery during the week preceding the interventional procedure * Conditions which prevent the intake of the double anti-platelet therapy for three months Exclusion Criteria: Lesion Related * Evidence of extensive thrombosis within target vessel before the intervention * Side branch \> 2 mm in diameter originating from the stent * Bifurcate lesion * Left main coronary artery stenosis * Multilesion percutaneous coronary intervention within the same artery (a main artery e.g., LCX and its side branch e.g. OMS are considered as different arteries) * Percutaneous coronary intervention of venous graft * Coronary artery occlusions of any type (e.g. acute or chronic) * In-segment stenosis of the native vessel within the 5 mm adjacent to the stent * Lesion within 1 mm of vessel origin Exclusion Criteria: Related to Concomitant Medication * Patient is intolerant to aspirin and/or the ADP-antagonists clopidogrel or has a history of neutropenia, thrombocytopenia induced by ADP-antagonists, or severe hepatic dysfunction prohibiting the use of clopidogrel * Patient has leucopoenia (leukocyte count \< 109/liter for more than 3 days) * Patient has neutropenia (ANC \< 1000 neutrophils/mm3 for more than 3 days) * Patient has a history of peptic ulcer or gastric/intestinal bleeding during the past 6 months * Patient has a history of thrombocytopenia (\< 100,000 platelets/mm3)