Background: It is unclear if patients with intermediate coronary artery lesions (40-70% of diameter reduction) benefit from percutaneous coronary intervention (PCI) as compared with pharmacological treatment.
Aim: To investigate whether PCI of intermediate coronary artery lesions may improve the outcome in this group of patients.
Methods: We performed a retrospective analysis of data of 232 symptomatic patients with intermediate coronary lesions. Hundred sixty five patients received only pharmacological treatment (group A) while 67 were treated with PCI with or without stent implantation (group B). Primary study endpoints were defined as follows: death (cardiac and non-cardiac), myocardial infarction, unstable angina, recurrent angina and coronary reintervention. Demographic and clinical variables were evaluated to identify predictors of the composite endpoint (exacerbation of angina, hospitalisation because of severe angina, restenosis in the intermediate coronary lesion, acute coronary syndrome and cardiac death).
Results: In group A, patients were treated with typical pharmacotherapy including beta-blockers, Ca-blockers, ACE-inhibitors, and antiplatelet drugs. In group B, 68 PCI procedures were performed in 67 patients and optimal pharmacotherapy was administered. The average age of patients in both groups was 58.0 ± 9.1 years and the majority were males (76%). Preinterventional coronary angiography showed that the intermediate lesions were most frequently localised in the left anterior descending (LAD) coronary artery; the next most frequent localisation was the right coronary artery (RCA). During the 12-month follow-up in 9 (13%) patients from the group B repeated PCI due to restenosis was performed, while in group A intervention was necessary in 7 (4%) of patients due to aggravation of symptoms (p = 0.01). The cumulative probability of restenosis after PCI in intermediate coronary lesions was 14%. Recurrent angina was more frequent in group B as compared to group A (34 vs. 19%; p = 0.005). None of the patients in any group died during 12 months of follow-up. In patients with intermediate coronary lesions, the independent predictors of the composite study endpoint were: history of previous percutaneous coronary angioplasty, type 2 diabetes, persistent ST-segment elevation in 12-lead ECG, heart rhythm disturbances, presence of the intermediate lesion in the LAD, and left ventricular dysfunction.
Conclusions: Patients with intermediate coronary artery stenoses could safely undergo pharmacological treatment and PCI may be postponed until aggravation of symptoms occurs. In the presence of predictors of the composite study endpoint, the use of intracoronary diagnostic methods may be considered to obtain more reliable and precise measurements of coronary stenosis severity.