Objectives: To investigate feasibility and safety of primary PCI in diabetic patients.
Background: Diabetic patients with acute myocardial infarction (AMI) have been shown to be at high risk for adverse clinical outcomes. Limited data is available on long term prognosis of diabetics treated with primary PCI.
Methods: Retrospective analysis of consecutive 67 diabetic patients and 211 non diabetic patients treated with primary PCI from 1/1995 to 12/1999, follow up for 38 +/- 12 months.
Results: The baseline characteristics were comparable in both groups. The mean age was 62 years in diabetic patients and 59 years in non diabetic patients. Hypertension (50% vs. 36%, p = 0.05), contraindications to thrombolytic treatment (13.4% vs. 5.7%, p = 0.037), cardiogenic shock (16.4% vs. 7.1%, p = 0.023), multivessel disease (34% vs. 23%, p = 0.07) and longer time delay to treatment (240 vs. 180 min., p = 0.05) were more often present in diabetic group. 47% of diabetic and 42% of nondiabetic patients received stents. The TIMI 2 or 3 flow rates were reached in 91% of diabetic patients and in 90% of nondiabetic patients, but TIMI 2 flow was found more often in diabetics (9% vs. 2.4%, p = 0.016). Higher rate of bleeding complications leading to significant change in the blood count (7.5% vs. 1.4%, p = 0.01) and higher 30 day mortality (11.9% vs. 5.2%, p = 0.05) was observed in diabetic group. However when the shock patients were excluded from the analysis, the 30 day mortality was different insignificantly in both groups (4.5% vs. 2.4%, p = 0.36). During follow up of 259 acute phase survivors 24 patients died. There was a trend to higher total long term mortality (22.3% vs. 13.2%, p = 0.07) and higher rate of nonfatal reinfarction (13.4% vs. 6.2%, p = 0.05) in diabetic group.
Conclusions: Primary PCI is safe and effective treatment of diabetic patients presenting with AMI. The higher rate of slow flow in infarct related artery after PCI observed in diabetics can be one of reasons for higher 30 day mortality in this group. Mean ischemic time in diabetics is behind the 4 hour border, where the possible benefit from reperfusion decreases. The main reason for higher mortality in our diabetic group was the higher rate of cardiogenic shock. Higher risk of bleeding complications at puncture site in diabetic patients can be explained by the lower quality of vessel wall.