Prognostic value of myocardial perfusion scintigraphy in asymptomatic patients with diabetes mellitus at high cardiovascular risk: 5-year follow-up of the prospective multicenter BARDOT trial.

BACKGROUND: The Basel Asymptomatic High-Risk Diabetics' Outcome Trial (BARDOT) demonstrated that asymptomatic diabetic patients with an abnormal myocardial perfusion scintigraphy (MPS) were at increased risk of major adverse cardiovascular events (MACEs) at 2-year follow-up. It remains unclear whether this finding holds true even for a longer follow-up. METHODS: Four hundred patients with type 2 diabetes, neither history nor symptoms of coronary artery disease (CAD), were evaluated clinically and with MPS. Patients were followed up for 5 years. Major adverse cardiovascular events (MACEs) were defined as all-cause death, myocardial infarction, or late coronary revascularization. RESULTS: At baseline, an abnormal MPS (SSS ≥ 4 or SDS ≥ 2) was found in 87 of 400 patients (22%). MACE within 5 years occurred in 14 patients with abnormal MPS (16.1%) and in 22 with normal scan (1.7%), p = 0.009; 15 deaths were recorded. Patients with completely normal MPS (SSS and SDS = 0) had lower rates of MACEs than patients with abnormal scans (2.5% vs. 7.0%, p = 0.032). Patients with abnormal MPS who had undergone revascularization had a lower mortality rate and a better event-free survival from MI and revascularization than patients with abnormal MPS who had either undergone medical therapy only or could not be revascularized (p = 0.002). CONCLUSIONS: MPS may have prognostic value in asymptomatic diabetic patients at high cardiovascular risk over a follow-up period of 5 years. Patients with completely normal MPS have a low event rate and may not need retesting within 5 years. Patients with an abnormal MPS have higher event rates and may benefit from a combined medical and revascularization approach.

Prognostic Usefulness of Cardiac Stress Test Modalities in Patients With Type 2 Diabetes Mellitus Who Underwent Myocardial Perfusion Scintigraphy (from the Basel Asymptomatic High-Risk Diabetics' Outcome Trial).

Our study aimed to assess predictors of the stress test technique used and to evaluate the impact of exercise level achieved on risk stratification in patients with asymptomatic type 2 diabetes without a previous coronary artery disease. Little is known whether co-morbidities of these patients predict the stress technique and whether physical performance provides risk stratification: 400 patients underwent clinical evaluation and myocardial perfusion scintigraphy (MPS) using physical or pharmacological stress. Physical patients were divided into 2 groups: achieving <6 and ≥6 METs, respectively. The mean follow-up time was 2 years. Major cardiac events (MACEs) included myocardial infarction and/or cardiac death. Independent predictors of pharmacological stress were a body mass index of >30 kg/m2 (hazard ratio 1.076, 95% confidence interval 1.027 to 1.127, p = 0.002) and a peripheral arterial disease (hazard ratio 2.888, 95% confidence interval 1.446 to 5.769, p = 0.003). Pharmacological patients had more MACE than physical patients (3.2% vs 1.0%, p = 0.03). Patients achieving <6 METs had a similar MACE rate as pharmacological patients (3.0% vs 3.2%, p = not significant) and more MACE than patients achieving ≥6 METs (3.0% vs 0.4%, p = 0.01). In patients achieving <6 METs and in pharmacological patients, MPS added an incremental prognostic value to pretest information (p values for global chi-square 0.012 and 0.04, respectively). In high-risk asymptomatic diabetic patients, co-morbidities were predictive of the stress technique used. Pharmacological patients had more MACE, similar to those unable to achieve 6 METs. MPS provided an incremental prognostic value in pharmacological patients and in patients with <6METs. In contrast, patients who were able to achieve ≥6 METs were at low risk and do not need further risk stratification.