Bridge to transplantation with the DeBakey VAD axial pump: a single center report

AIMS

To report our experience with a left ventricular assist device axial pump as a bridge to transplantation: the DeBakey Ventricular Assist Device (VAD).

METHODS

From February 1999 to February 2002, nine patients (among which eight males), with a mean age of 47 years, all in NYHA functional class IV, were proposed for a bridge to transplantation with the DeBakey VAD. Five patients had primary dilated cardiomyopathy, four had ischemic cardiomyopathy. All the patients had inotropic support prior to the intervention (dobutamine with a mean dose of 12 mcg/kg per min), six had an intra-aortic counterpulsation, four presented ventricular rhythm disorders. Interventions were performed through sternotomy alone (no need for an abdominal pocket) under extra-corporeal circulation on beating heart (except in one patient suffering from an apical thrombosis for which cardioplegic arrest was performed) as followed: implantation of the apical inflow cannula, tunneling of the percutaneous cable, implantation of the outflow graft under aortic side clamping, starting of the DeBakey VAD during CPB weaning-off.

RESULTS

Mean support duration was 81+/-62 days (16-224 days). Eight reoperations were required (three for bleeding or cardiac tamponade, one for haemoperitoneum, one for aortic bifurcation thrombectomy, one for right ventricular assist device implantation, two for iterative replacements of the DeBakey VAD). A significant hemolysis was observed in two patients. No device infection or dysfunction were observed. Secondary recovery of a pulsed flow was observed either clinically or by Echo-Doppler in six patients. Five patients were transplanted, four died prior to transplantation (three from multi-organ failure on post-operative day 35, 16 and 50, respectively, and the last patient was found disconnected at day 109).

CONCLUSIONS

The DeBakey VAD is at the origin of renewed interest for continuous flow assist devices. Still under evaluation, the advantages of miniaturization and facility of implantation of this new device seem to be promising.

[Fibrinolytic inhibitors and prevention of bleeding in cardiac valve surgery. Comparison of tranexamic acid and high dose aprotinin]

In order to assess the effects of tranexamic acid in comparison to the high dose regimen of aprotinin recommended by Royston and considered to be the reference in postoperative bleeding in cardiac surgery, 35 consecutive patients were randomised to two groups according to the product prescribed. The global postoperative bleeding was comparable in the two groups (p = 0.49). One surgical reoperation for haemostasis was required in the reference group. There was one case of renal failure in the same group due to cardiac failure. No thrombotic complications were observed. Platelet function, as judged by the bleeding time and platelet aggregation to ristocetin, was the same in the two groups. The D-dimers remained low in both groups, reflecting the absence of intravascular coagulation and fibrinolysis. Tranexamic acid was as effective and as safe as high dose aprotinin. These two substances, in addition to their fibrinolytic inhibitory activity, conserved platelet protection by blocking the action of plasmin. These results seem to justify the preventive use of tranexamic acid from the moment of skin incision, especially in reoperation.