Credit: UAB Hospital
In a large study, patients who received red blood cell (RBC) transfusions after percutaneous coronary intervention (PCI) had a higher risk of in-hospital heart attack, stroke, and death than their non-transfused peers.
The retrospective study included data on nearly 2 million patients who underwent a PCI at hospitals across the US.
The research revealed considerable variation in transfusion practices for this patient population, although the overall rate of transfusion was low.
This makes sense, as giving RBC transfusions to patients with coronary artery disease is controversial, according to the study authors.
They said there is a growing body of evidence suggesting that transfusion in the setting of acute coronary syndromes (ACS) and in hospitalized patients with a history of coronary artery disease may be associated with an increased risk of heart attack and death.
Furthermore, current guideline statements are cautious about recommending transfusion in hospitalized patients with a history of coronary artery disease and make no recommendation on transfusion in the setting of ACS, citing an absence of definitive evidence.
With this in mind, Matthew W. Sherwood, MD, of Duke Clinical Research Institute in Durham, North Carolina, and his colleagues examined transfusion practice patterns and outcomes in 1,967,218 patients (2,258,711 visits) who underwent PCI from July 2009 to March 2013 at 1431 US hospitals.
The team reported their findings in JAMA.
Overall, 2.1% of patients had a transfusion. However, transfusion practices varied among the hospitals. The unadjusted transfusion rates ranged from 0% to 13%. Overall, 96.3% of hospitals transfused less than 5% of patients, and 3.7% of hospitals transfused 5% of patients or more.
Risk-standardized rates of transfusion by hospital ranged from 0.3% to 9.3%. The risk was adjusted for factors such as age, sex, body mass index, ACS presentation, PCI status, history of congestive heart failure, etc.
Compared to no transfusion, receiving an RBC transfusion was associated with a greater risk of heart attack (4.5% vs 1.8%), stroke (2.0% vs 0.2%), and in-hospital death (12.5% vs 1.2%), irrespective of bleeding complications.
Patients were more likely to receive a transfusion if they were older, female, and had hypertension, diabetes, advanced renal dysfunction, and prior heart attack or heart failure.
The researchers speculated that the variation in transfusion practice patterns observed in this study may be related to several factors, including previously held beliefs about the benefit of transfusion and recently published data indicating the lack of benefit and potential hazard associated with transfusion.
The team said these data highlight the need for randomized trials of transfusion strategies to guide practice in patients undergoing PCI. And until these trials provide more definitive answers, clinicians should try to reduce the risk of bleeding and, therefore, the need for transfusion in patients undergoing PCI.
