We report the case of a patient presenting an intra-myocardial hematoma after recanalisation of a saphenous aorto-right coronary arterial bypass graft implanted 10 years previously after posterior myocardial infarction. The intra-myocardial hematoma occurred immediately after recanalisation of the graft and was complicated by transient complete atrio-ventricular block. An acute increase of coronary capillary perfusion pressure may cause intramyocardial bleeding when capillary permeability is altered by prolonged ischemia or necrosis. In this case the resulting hematoma was limited to the segment of left ventricular wall affected by the previous necrosis and there was no further myocardial damage.