Incidence and prognostic importance of silent ischaemia after PTCA: a prospective study.

To evaluate the influence of PTCA on symptomatic and asymptomatic ischaemic episodes in 94 patients, 24-h ambulatory, electrocardiographic Holter recordings were obtained before and after successful PTCA. Sixty-four per cent of patients had one-vessel disease, 28% two-vessel disease and 8% had three-vessel disease. Ischaemic episodes were present in 36% of patients before PTCA, of which 71% were silent; after PTCA, 23% of patients had ischaemic episodes, of which 98% were silent; thus silent ischaemic episodes were improved by PTCA to a lesser degree than symptomatic ischaemic episodes. Successful PTCA lead to a significant reduction in total number and duration of ischaemic episodes but not to a complete abolition. Patients with silent ischaemic episodes after PTCA had also a higher incidence of silent ischaemic episodes before PTCA. Functional and haemodynamic improvement was comparable in patients with and without silent ischaemic episodes. No specific cause for the persistent or newly appearing silent ischaemic episodes after PTCA could be identified; they are not indicative of an inadequate dilatation and cannot be considered as a risk factor for early restenosis. A possible explanation could be a traumatically induced, increased vascular tone in susceptible patients. [ABSTRACT FROM PUBLISHER]