Bleeding events are one of the most significant potential side effects of transcatheter aortic valve replacement (TAVR). Can new and improved definitions for TAVR-related bleeding help cardiologists and other members of the heart team provide better care?
A team of specialists hoped to find out, sharing its findings in JACC: Cardiovascular Interventions.[1]
“Because of its lower invasiveness, TAVR has been associated with a 50% reduction in major bleeding events compared with conventional surgery,” wrote first author Marisa Avvedimento, MD, a cardiologist with the Quebec Heart & Lung Institute in Canada, and colleagues. “Over time, technical refinements, increased operator experience, and the gradual shift of TAVR candidates toward lower surgical risk have led to a reduction in periprocedural bleeding rates. However, bleeding still remains one of the most important procedural drawbacks, which significantly increases the morbidity and mortality risks.”
Back in 2021, researchers explained, the Valve Academic Research Consortium (VARC)—an international group of cardiologists, imaging specialists, device manufacturers and regulators—released new definitions and endpoints related to various aspects of aortic valve research.[2] VARC’s goal was to ensure researchers all over the world are on the same page when discussing treatments such as TAVR and surgical aortic valve replacement. One of the group’s biggest changes was new VARC-3 bleeding definitions, which were updated to be much more descriptive and capture more incidents.
Hoping to evaluate the effectiveness of these new definitions, Avvedimento et al. used them to categorize a real-world TAVR population of patients who underwent the procedure at their own facility. The researchers evaluated data from more than 2,300 patients treated from 2007 to 2022. Nearly 32% experienced an early or late bleeding event following TAVR.
Bleeding events were categorized based on VARC-3 criteria:
- Type 1 events require medical assistance, but not surgical or percutaneous intervention.
- Type 2 events are similar to type 1 events, but require a more significant blood transfusion or a hemoglobin decrease of 3-5 g/dL.
- Type 3 events are much more significant. These events are linked to hypovolemic shock, severe hypotension, the use of vasopressors or a hemoglobin decrease of ≥5 g/dL. Bleeding that requires surgery or another intervention is viewed as a type 3 event.
- Type 4 events, meanwhile, result in the patient’s death.
Using these criteria, the authors found that 22.2% of recorded bleeding events were type 1, 52.4% were type 2, 19.6% were type 3 and 5.8% were type 4.
The primary vascular access site was the most common source of early bleeding events, and gastrointestinal locations were the most common source of late bleeding events. Early bleeding events were more common among women. Thoracotomy access, the use of a larger sheath and dual antiplatelet therapy prior to the procedure all increased a patient’s risk of an early bleeding event, and the use of radial artery for secondary access helped lower that risk.
Type 2 and type 3 bleeding events were both associated with a heightened risk of death after 30 days and after one year.
“Although minor bleeding showed no impact on mortality, major and life-threatening bleeding significantly affected short- and long-term survival,” the authors wrote. “The complex interplay between bleeding occurrence and clinical outcomes reaches beyond heightened mortality. Indeed, bleeding occurrence was associated with longer hospitalization, which is in line with previous evidence.”
Another key takeaway from the group’s analysis was that VARC-3 bleeding definitions capture more events than the old VARC-2 definitions. However, it remains unclear if this has resulted in an “overestimation” of bleeding events or if it truly helps specialists gain a better understanding of when patients face a significant risk of mortality.
“Further large-scale studies are needed to elucidate the prognostic performance of the newly adopted VARC-3 bleeding endpoint and to better define the impact of nonovert procedural blood loss,” the authors wrote.
Click here to read the full study in JACC: Clinical Interventions, an American College of Cardiology journal.
Michael has more than 16 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.