A randomised, double-blind, placebo-controlled trial to evaluate the role of intracoronary injection of progenitor cells compared to placebo injection in patients with Dilated Cardiomyopathy who have been pre-treated with G-CSF (Granocyte™) injections for 5 days, and patients treated with a 5 day course of G-CSF (Granocyte™) injection only compared to placebo injection

Inclusion Criteria:

• Symptomatic patients with a confirmed diagnosis of dilated cardiomyopathy (NYHA II-III) attending their local 'Heart Failure clinic' who are on optimal heart failure treatment, under supervision from their physician or heart failure nurse specialist, and have no other treatment options
• Patients who are NYHA II that have been hospitalised with a dilated cardiomyopathy related condition
• Coronary angiography will be performed where necessary to confirm the diagnosis and ensure no other conventional treatment options are indicated
• Prior to recruitment to the study patients at risk of ventricular arrhythmia will have undergone electrophysiological assessment and appropriate clinical management (including implantable defibrillator insertion) where indicated (as per NICE guidelines)

Exclusion Criteria:

• NYHA I
• Referral hospitals most recent documented ejection fraction of >45% (any imaging modality)
• The presence of cardiogenic shock
• The presence of acute left and/or right sided pump failure as judged by the presence of pulmonary oedema and/or new peripheral oedema
• Known severe pre-existent left ventricular dysfunction (with a documented ejection fraction of <10% from referral hospital) prior to randomisation
• Congenital cardiac disease
• Cardiomyopathy secondary to a reversible cause that has not been treated e.g. thyroid disease, alcohol abuse, hypophosphataemia, hypocalcaemia, cocaine abuse, selenium toxicity & chronic uncontrolled tachycardia
• Cardiomyopathy in association with a neuromuscular disorder e.g. Duchenne's progressive muscular dystrophy
• Previous cardiac surgery
• Contra-indication for bone marrow aspiration
• Known active infection
• Known infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), HTLV or syphilis.
• Chronic inflammatory disease requiring ongoing medication
• Serious known concomitant disease with a life expectancy of less than one year
• Follow-up impossible (no fixed abode, etc)
• Patients with an irregular heart rhythm (AF allowed if paced in a regular rhythm)
• Patients with renal impairment (Creatinine >200mmol/L)
• Neoplastic disease without documented remission within the past 5 years
• Weight>140kg
• Subjects of childbearing potential