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Objective: The objective of this paper is to present the results from Spiral Pump clinical trial after design modifications performed at its previous project. This pump applies axial end centrifugal hydraulic effects for blood pumping during cardiopulmonary bypass for patients under cardiac surgery., Methods: This study was performed in 52 patients (51% males), between 20 to 80 (67±14.4) years old weighing 53 to 102 (71.7±12.6) kg, mostly under myocardial revascularization surgery (34.6%) and valvular surgery (32.8%). Besides the routine evaluation of the data observed in these cases, we monitored pump rotational speed, blood flow, cardiopulmonary bypass duration, urine free hemoglobin for blood cell trauma analysis (+ to 4+), lactate desidrogenase (UI/L), fibrinogen level (mg/dL) and platelet count (nº/mm3)., Results: Besides maintaining appropriate blood pressure and metabolic parameters it was also observed that the Free Hemoglobin levels remained normal, with a slight increase after 90 minutes of cardiopulmonary bypass. The Lactate Dehydrogenase showed an increase, with medians varying between 550-770 IU/L, whereas the decrease in Fibrinogen showed medians of 130-100 mg/dl. The number of platelets showed a slight decrease with the medians ranging from 240,000 to 200,000/mm3. No difficulty was observed during perfusion terminations, nor were there any immediate deaths, and all patients except one, were discharged in good condition., Conclusion: The Spiral Pump, as blood propeller during cardiopulmonary bypass, demonstrated to be reliable and safe, comprising in a good option as original and national product for this kind of application.

Objective: The objective is to present the results of the application this device in experimental animals unloading only the left ventricle., Methods: Between June 2002 and October 2009, were implanted in 27 calfs with age between 2½ to 4 months and 80 to 100 kg of weight, with general anaesthesia and controled ventilation, by mean of left thoracotomy a cannula in the apex of VE and a lateral anastomose of a GTFE vascular graft tube in the descending portion of the thoracic aorta, both connected to the device implanted below the diaphragm in the subcutaneous (24) and intrathoracic (three). The cardiopulmonary bypass (BP) was used in five calves, and directly introduce the outflow cannula in 22., Results: During the implant two and in the first hours of the post operative period (PO) three deaths were observed, one related to the device. The survival between the first and the six PO day was found in 17 calves and between day 8 and day 31 (PO) in five all caused by clinical/surgical problems, and related to the device. The hemodynamic impact by the systemic pressure analysis showed 20 to 40 mmHg increase and the laboratory parameters showed lower levels of traumatic impact to the blood and a good biocompatibility., Conclusions: This kind of research is arduous and complex where at each experiment many problems are indentified in the implantability and in the device, which are sistematic correct, to became device/procedure safe and effective.

Introduction: This paper addresses an original project that encompasses the conception, development and clinical application of a helical bypass pump called the Spiral Pump, that uses the association of centrifugal and axial propulsion forces based de the Archimedes principle. This project has obtained a Brazilian Patent and an International Preliminary Report, defining it as an invention., Methods: The aim of this work was to evaluate the hemodynamic capacity and the impact of its application on blood cells by means of experimental in vitro tests, including hydrodynamic efficiency, effect on hemolysis and flow visualization. Moreover, in vivo experimental tests were carried out on lambs that were submitted to cardiopulmonary bypass for six hours and in 43 patients submitted to heart bypass surgery using the Spiral Pump., Results: When the rotor-plastic casing gap was 1.5mm, the flow generated was nearly 9 L/min, the pressure was greater than 400 mmHg at 1500 rpm, and the normalized hemolytic indexes were not greater than 0.0375 g/100L in high-flow and pressure conditions. Additionally, by the flow visualization techniques, stagnation was not seen inside the pump nor was turbulence identified at the entrance or exit of the pump, or at the ends of the spindles. In the in vivo tests using cardiopulmonary bypasses for 6 hours in lambs, the pump maintained adequate pressure rates and the free hemoglobin levels ranged between 16.36 mg% and 44.90 mg%. Evaluating the results of the 43 patients who used this pump in heart bypass operations we observed that the free hemoglobin ranged from 9.34 mg% before to 44.16 mg% after surgery, the serum fibrinogen was from 236.65 mg% to 547.26mg%, platelet blood count from 152,465 to 98,139 and the lactic dehydrogenase from 238.12mg% to 547.26mg%. The Activated Coagulation Time was close to 800 seconds during the bypass., Conclusion: The Spiral Pump was very effective in generating adequate flow and pressure and caused no excessive harm to the blood cells.