Purpose: Revascularizing procedures like percutaneous transluminal coronary angioplasty (PTCA) aim at reducing the incidence and severity of myocardial ischemia. To evaluate this, continuous Holter ST analysis is a possible method.
Design: 41 patients (35 men, 6 women) with stable angina pectoris had continuous twenty-four-hour two-channel Holter registration (V5/aVF-analogous leads) recorded before and after PTCA. Transient myocardial ischemia (TM) was defined as 0.1 mV ST depression or more 80 msec after the J point for one minute or more.
Findings: PTCA was successful for 37 patients (90%). Eleven of these had a total of 53 episodes of TM, 36 (68%) before and 17 (32%) after PTCA (p less than 0.05). Fifteen episodes (28%) were symptomatic, and 38 (72%) were asymptomatic. Six patients had TM after successful PTCA, 5 of whom had one-vessel disease and a clinically uncomplicated course. One patient had multivessel disease, with only one vessel dilated. Follow-up angiograms for 9 of the 11 patients with TM revealed 5 restenoses. There was no significant correlation between TM after PTCA and subsequent restenosis (p greater than 0.05).
Implications: TM is common in patients with stable angina pectoris. The incidence significantly decreases after successful PTCA, but TM is seen also with a clinically uncomplicated course. In multivessel disease this is consistent with incomplete revascularization, whereas in single-vessel disease the most likely cause is intermittent spasm or thrombosis. TM after successful PTCA does not seem to be a predictor of restenosis.