Use of a Percutaneous Left Ventricular Assist Device For High-Risk Cardiac Interventions and Cardiogenic Shock
- Volume 22 - Issue 8 - August, 2010
- Posted on: 8/6/10
- 0 Comments
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The need for transfusion during or after PVAD support has infrequently been reported in the literature. The preclose technique has been demonstrated to be an effective method of managing large- bore arterial cannulae.10 A large series of 20 patients all managed with the preclose technique prior to PVAD insertion demonstrated a low vascular complication rate, but transfusion rates were not reported.11 In one of the two randomized PVAD versus IABP trials, 19 of 21 patients receiving PVAD support required blood transfusion. This was twice as frequent as in the IABP group.2 Such findings are similar to our experience. It does seem logical that using the PVAD during PCI may have higher associated bleeding risks than when the PVAD is used solely for a bridge to transplant. Contemporary PCI involves not only systemic anticoagulation, but various antiplatelet strategies as well.22,23
The high rate of post-procedure transfusion could not be explained by baseline anemia (present in 15 patients) or prolonged access-site bleeding or hematoma. There are likely multiple explanations for frequent transfusion. Blood loss may occur with de-airing of the cannulae prior to PVAD initiation, the interventional procedure itself, or during sequential dilation of arterial and venous puncture sites to accommodate large-bore catheters. Despite returning the blood remaining in the pump housing and tubing to the femoral vein after PVAD, there is a small volume of blood lost in the discarded cannulae, tubing and device. Precautionary transfusion post procedure may also occur and be unnecessary. As bleeding itself is a strong risk factor for poor patient outcomes,24,25 adjustments to minimize blood loss and transfusion are a primary goal as this interventional PVAD program moves forward.
Certain high-risk patients are unable to undergo cardiac surgery due to their critical status and comorbidities. Other patients do not have the cardiovascular reserve to tolerate advanced percutaneous procedures to treat coronary and valvular diseases. The ability to safely initiate and maintain near-total circulatory support in the catheterization laboratory with the PVAD is a giant step forward for interventional cardiology. This series demonstrates that PVAD has a role for that identifiable cohort of patients with extreme procedural risk profiles. This tool can be safely used in a diverse and aged population for CS and during complex interventions, though transfusion and bleeding may be common. It can be expected that percutaneous devices like the TandemHeart will be used to support the next generation of catheter-based revascularization and valve therapies.