The use of a potassium ferrate hemostatic patch in addition to TR Band for transradial-access (TRA) catheterization allows for faster deflation of the TR Band without an excess of hematomas or radial artery occlusion (RAO) in comparison with the TR Band alone, according to late-breaking trial results released Wednesday at the Society for Coronary Angiography and Interventions (SCAI) 2021 Virtual Scientific Sessions.
Arnold Seto, MD, MPA, of the Long Beach Veterans Affairs Medical Center, California, presented the results of STAT2, an investigator-initiated, unsponsored research trial. Biolife Inc., the manufacturer of StatSeal, had no involvement in the design or conduct of this trial.
TRA is the preferred approach for cardiac catheterization, Seto said, because of reduced bleeding and complications, higher patient comfort, and improved throughput and increased chance of same-day discharge from the catheterization laboratory.
The TR Band (Terumo), an air-bladder bracelet, is most frequently used to achieve hemostasis. However, there is no standardized protocol for TR Band deflation.
Early TR Band deflation may reduce observation time and radial artery occlusion (RAO) following TRA. For example, one study shows that 2-hour inflation reduces RAO in comparison with 6-hour inflation (RAO in 12% of the 6-hour group vs. 5.5% of the 2-hour group, p=0.025).
But reducing compression times too much might increase bleeding. For example, in another study, patients undergoing 20-minute compression had a higher rate of hematomas as compared to those with 1-hour compression (6.7% vs. 2.5%, p=0.015), and the shorter-compression group had an increased need for recompression (36% vs. 16%, p=0.01).
The StatSeal is a topical hemostatic patch that is used as an adjunct to compression. It has a hydrophilic polymer, which dehydrates and concentrates blood solids, and potassium ferrate, which stops bleeding while blood solids and proteins stack underneath the seal. This process works independently of the body’s coagulation cascade.
The StatSeal is filled with blood and then applied around the TR Band. The TR Band is inflated to occlusive pressure for 20 minutes, then partially deflated for another 40 minutes until being fully deflated. The patch is left on overnight, and the patient removes it the following day.
The STAT pilot study showed a significantly reduced time to full TR Band deflation (TR Band alone 160 minutes vs. TR Band plus StatSeal 43 minutes, p<0.001). Seto acknowledged that the TR Band-alone group was not allowed to have the TR Band deflated before 120 minutes, which while the standard of care at the time, was a bias in the study design in favor of the StatSeal intervention.
The study also showed a trend toward more hematomas in the StatSeal group.
STAT2 had 443 patients randomized to TR Band with StatSeal (223) or TR Band alone (220). There was no minimum dose of unfractionated heparin dose, and the deflated TR Band was left in place for 30 minutes to remind the patient not to move. Finally, unlike the STAT trial, deflation had to be started at 60 minutes for all patients, those receiving StatSeal and those with TR Band alone.
The primary endpoint was time to TR Band deflation without rebleeding. Secondary outcomes included RAO, hematoma or other bleeding requiring intervention beyond TR Band reinflation.
The two groups were well-matched except that the StatSeal group had a higher percentage of male patients (81.9% StatSeal vs. 69.5% control, p=0.03). Most patients underwent diagnostic catheterization, although 27% did undergo percutaneous coronary intervention (PCI).
TR Band deflation time was significantly lower in the StatSeal group (65.9±14.1 minutes) than in the TR Band-alone group (112.8±56.3 minutes; p<0.001). Also, there was no rebleeding requiring TR Band reinflation in the StatSeal group, but 67.3% of patients in the TR Band-alone group experienced this bleeding (average 2.3±1.3 reinflations required).
In the PCI subgroup, the same pattern emerged. PCI patients in the StatSeal group had a significantly lower TR Band deflation time (68.1±15.3 minutes vs. 138.2±62.0 minutes, p<0.001).
Hematomas were higher in the TR Band-alone group, as was bleeding requiring intervention. RAO was relatively low in both groups (StatSeal 0.4% vs. TR Band-alone 0.9%) despite 41% of patients having <5,000 units of unfractionated heparin, which Seto said was one of the trial’s major findings.
And complications were numerically lower in the StatSeal group (4.5% vs. 8.6%, p-0.08), but they were significantly lower among PCI patients in the StatSeal group (10.0% vs. 24.2%, p=0.04).
The trials’ limitations include being powered for procedural, but not clinical, outcomes; an inability to blind investigators and subjects; and no difference in discharge due to pre-existing facility protocols.
Seto said the study demonstrates that the use of the StatSeal safely facilitates early deflation (60 minutes) of the TR Band after TRA without an excess of hematomas or RAO. Early TR Band deflation without the StatSeal, on the other hand, was associated with increased rebleeding requiring TR Band reinflation and longer compression time. RAO occurred rarely with early deflation regardless of heparin dose.
Seto noted that the trial shows the potential for the StatSeal to help with early discharge after catheterization, especially PCI; reduce nursing burden, time and costs; and reduce unfractionated heparin doses for diagnostic procedures.