Impact of Baseline Anemia in Patients Undergoing Transcatheter Aortic Valve Replacement: A Prognostic Systematic Review and Meta-Analysis.

Transcatheter aortic valve replacement (TAVR) is currently the treatment of choice for patients aged ≥75 years with severe aortic stenosis. Preoperative anemia is present in a large proportion of patients and may increase the risk of post-procedural complications. The purpose of this prognostic systematic review was to analyze the impact of baseline anemia on short- and mid-term outcomes following TAVR. A computerized search was performed on PubMed and Web of Science databases for studies published between January 2013 and December 2022. Primary outcomes were 30-day need for transfusion, acute renal failure, 30-day and mid-term mortality, and readmission during the first year post-TAVR. Data were analyzed via random effects model using inverse variance method with 95% confidence intervals. Eleven observational studies met our eligibility criteria and included a total of 12,588 patients. The prevalence of baseline anemia ranged between 39% and 72%, with no relevant sex differences. Patients with preprocedural anemia received more blood transfusions [OR: 2.95 (2.13-4.09)]), and exhibited increased rates of acute kidney injury [OR:1.74 (1.45-2.10)], short-term mortality [OR: 1.47 (1.07-2.01], and mid-term [OR: 1.89 (1.58-2.25)] mortality following TAVR compared with those without anemia. Baseline anemia determined an increased risk for blood transfusion, acute kidney injury, and short/mid-term mortality among TAVR recipients.