PTCA: periprocedural platelet activation. Part II of the Duesseldorf PTCA platelet study (DPPS)

Percutaneous transluminal coronary angioplasty (PTCA) with its various manipulations could create a dangerous, sudden haemostatic response. This study was performed to investigate PTCA-induced periprocedural changes in platelet activation and its consequences.

Twenty-five consecutive patients admitted for elective PTCA were preclassified as having or not having circulating activated platelets. Blood samples were taken for platelet activation marker analysis before, six times during and 2 h after PTCA. Intravascular platelet activation was analysed by flow cytometry to measure activation-dependent surface markers thrombospondin, P-selectin (CD62) and lysosomal GP53 (CD63).

PTCA was associated with a significant reduction of peripheral platelet count. The initiation of the PTCA procedure led to a significant loss of more than 50% of the degranulated, activated platelets. After PTCA, the number of degranulated, activated platelets uniformly increased.

We conclude that PTCA can induce consumption, particularly of preactivated platelets, and lead to sustained platelet activation after the procedure. This might explain why preactivated patients are at increased risk of suffering periprocedural ischaemic events and why increased thrombogenicity favours acute flow disruption and the progression of coronary stenosis at the lesion site.