Centrifugal pump or pneumatic ventricle for short-term mechanical circulatory support?

Two comparable groups of four Holstein calves were implanted with different left ventricle assist devices: the Centrimed centrifugal pump (CP) (Sarns Inc.) or the UTAH 85 VAD pneumatic ventricle (University of Utah). Operative procedure, inflow and outflow cannulae, monitoring, heparinization, were identical in both groups. No transfusion was ever required. The study was terminated after three days and autopsy was performed on the calves. Left ventricular unloading provided by both devices was complete (LVEDP less than 1 mmHg) and identical. LV bypassed flow rate was higher in CP (0.045 L/min/kg) than in UTAH 85 VAD (0.035 L/min/kg) but with no statistical difference. Blood trauma was comparable in the two groups. Daily blood samples did not show any significant changes from baseline values in creatinine, hematocrit, fibrinogen. Platelet loss from initial level was 30%; serum lactate dehydrogenase rose 150% with no significant difference in the two groups; plasma free hemoglobin never reached significant values. At autopsy, thrombotic deposits on cannuale and renal infarction rate were similar. CP housing had to be changed every day, whereas no technical failure was ever observed with the UTAH 85 VAD. Clinical response and blood damage of the two pumps used as LVAD were the same. Considering the CP has to be replaced every 24 h, the cost of three CP's would be comparable to one Utah UVAD-85 if polyurethane tricusp semi-lunar valves are used in the latter. Until the UTAH-85 VAD becomes commercially available, simple valveless low-cost CP are very attractive for short-term mechanical support.

[Home thrombolysis for myocardial infarction. A multicenter study of the feasibility and evaluation of short-term prognosis]. / Thrombolyse à domicile pour l'infarctus du myocarde. Etude multicentrique de faisabilité et évaluation du pronostic à court terme.

It has been proven since 1986 that in myocardial infarction the sooner thrombolysis is performed the better. Forty-four patients were selected to enter a double-blind randomized trial in which they received either an acylated plasminogen streptokinase activator complex or a placebo. The injections were given intravenously at home within the first 3 hours (within the first 2 hours in 26 of them), by doctors from Mobile care units. This home treatment in the acute phase made it possible to gain 75 minutes on average, and up to 90 minutes when it was performed by an anaesthetist trained in emergency management. No serious complication, such as haemorrhagic or allergic reaction, occurred, and arrhythmia was no more frequent in the treated group than in the placebo group. Home thrombolysis did not delay admission to a cardiology Intensive Care unit (66 min. versus 64 min). Mean coronary patency was 75 per cent, and up to 82 per cent, in patients treated within 2 hours of the first symptoms. There was no significant difference between areas of reperfused or not reperfused patients in relation to time (P less than 0.08). Diagnosis sensitivity was 100 per cent. Thus, home thrombolysis is feasible and safe when performed by trained emergency medical teams and when criteria for inclusion and exclusion are fulfilled.