The Second Randomized Intervention Treatment of Angina - RITA II

Description:

Not available.

Hypothesis:

To compare two initial strategies for patients with coronary artery disease: initial coronary angioplasty vs. conservative medical therapy.

Study Design

Study Design:

Patients Screened: Not given
Patients Enrolled: 1018

Patient Populations:

Native coronary artery lesions; single or multivessel coronary disease; > 70% diameter stenosis.

Exclusions:

Patients in whom myocardial revascularization was mandatory; patients with previous myocardial revascularization, left main coronary artery disease, significant valvular disease, or concomitant life threatening noncardiac disease were excluded.

Primary Endpoints:

Composite of death and non-fatal MI at 5 years.

Drug/Procedures Used:

Randomization to conservative medical therapy or balloon angioplasty (PTCA). Patients assigned to PTCA underwent the procedure within 3 months of randomization.

Principal Findings:

Of the 504 patients randomized to initial PTCA strategy, 471 (93%) underwent the intended procedure within a median time of 5 weeks from randomization. PTCA was successful in 93% of the 642 attempted coronary lesions. Seven patients (1.5%) randomized to PTCA underwent emergency CABG. During follow-up 2.2% of the PTCA vs 1.4% of the conservative therapy group died (p=0.32). Cardiac mortality was 0.99% vs 0.60%, respectively. Nonfatal myocardial infarction occurred in 4.2% of the PTCA group vs only 1.9% in the medical group. The difference was due to 7 randomized procedure related myocardial infarctions in the PTCA group. Death or definite myocardial infarction occurred in 6.3% of the PTCA group vs 3.3% of the medical group (relative risk 1.92;95% CI 1.08-3.41; p=0.02). The absolute treatment difference was 3.0%(95% CI 0.4%-5.7%). During follow-up 7.9% of the PTCA group and 5.8% of the medical group underwent CABG. Additional nonrandomized PTCA was performed in 12.3% of the PTCA group vs 19.6% of the medical group. In this group, the risk of requiring CABG or PTCA within 1 year of randomization was 15.4%. Improvement in reported angina was greater in the PTCA group, with a 16.5% excess of grade 2+ angina in the medical group after 3 months of therapy (p<0.001). However, after 2 years of follow-up, the medical group had only 7.6% excess of grade 2+ angina (p=0.02). Bruce treadmill exercise test was performed by about 90% of the patients at each follow-up. After 3 months the PTCA group exercised longer than the medical group (mean difference 35 seconds; 95% CI 20-51 seconds; p<0.001). However, the difference was attenuated at 1 year to 25 sec (95% CI 7-42 sec;p=non-significant). The beneficial effects of PTCA over medical therapy were more pronounced in patients with more severe angina at baseline.

Interpretation:

In patients with stable coronary artery disease suitable for either medical therapy or PTCA, initial strategy of PTCA was associated with greater symptomatic improvement, especially in patients with more severe baseline symptoms. However, the differences between the PTCA and medical therapy tended to decrease over time and the initial PTCA strategy was associated with a significant excess of mortality and nonfatal myocardial infarction.

References:

1. Lancet 1997;350:461-8.

Clinical Topics: Cardiac Surgery, Invasive Cardiovascular Angiography and Intervention, Atherosclerotic Disease (CAD/PAD), Aortic Surgery, Interventions and Coronary Artery Disease

Keywords: Risk, Coronary Artery Disease, Myocardial Infarction, Follow-Up Studies, Coronary Artery Bypass, Angioplasty, Balloon, Coronary, Exercise Test


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