Increased in vitro platelet aggregation in hypertriglyceridemias.

Platelet aggregation induced by ADP and collagen was monitored in 25 patients with increased serum levels of triglycerides (7 HLPs type IIb, 14 type IV, 4 type V patients) and compared with a group of 10 normolipidaemic control persons. Platelet aggregation was studied simultaneously in platelet rich plasma (PRP) by both turbidometric and impedance technique and also in whole blood (WB) by the impedance method. Whereas platelet aggregation testing by turbidometry was limited by the optical density of the plasma samples in hypertriglyceridemia, the aggregation process could easily be registered in PRP and WB using the impedance method. Threshold aggregatory concentrations with both agonists were significantly lower for all three groups of HLP.