Background Primary percutaneous intervention (PPCI) is the treatment of choice for ST elevation myocardial infarction (STEMI) but robust evidence in the very elderly is lacking. We compared PPCI outcomes between different age quartiles (quartile 1<60 years, quartile 2≥60 to<70 years, quartile 3≥70 to<80 years, quartile 4≥80 years). Methods Retrospective observational analysis of our Morriston Tertiary Cardiac Center (Abertawe Bro Morgannwg University Health Board) patients from 2005 to 2010 with STEMI who underwent PPCI. Results Of 434 patients, 57 (13%) were in quartile 4 (≥80 years). In older age quartiles, patients were less likely to receive a drug eluting stent (DES, P=0.001) or glycoprotein IIb/IIIa inhibitor (GPI, P<0.0001). Increase in age was associated with reduced time to survival (β-coefficient:?0.192, t:?3.70, 95%CI:?4.91 to?1.50, P<0.0001) as was the presence of cardiogenic shock (β-coefficient:?0.194, t=3.77, 95%CI: ?5.26 to?1.65, P<0.0001). Use of GPI was associated with increased time to survival (β-coefficient: 0.138, t= 2.82, 95%CI:1.58–8.58, P=0.005) but older age quartiles were less likely to receive GPI (P<0.0001). In-hospital mortality (1.8%quartile 1, 3.6%quar-tile 2, 10.9%quartile 3 and 12.3%quartile 4, P=0.002) and 1-year mortality (5.4%quartile 1, 5.5%quartile 2, 16.8%quartile 3 and 24.6%quartile 4, P<0.0001, respectively) was significantly higher in older age quartiles. Conclusions Increased short term and intermediate term mortality is seen in the very elderly after PPCI. Age and cardiogenic shock were prognostic factors. Intervention should not be based on age alone and awareness regarding prognostic factors can help improve management.