Transient ischemic dilatation with adenosine 99mTc-sestamibi stress: prognostic significance in patients with normal myocardial perfusion.

OBJECTIVE To determine the significance of transient ischemic dilatation (TID) in patients with normal perfusion on adenosine stress/rest. METHODS We analyzed 430 consecutive patients with normal perfusion on 2-day adenosine stress/rest 99mTc-sestamibi. A group of 70 patients with Framingham 10-year coronary heart disease risk   mean + 2SD (TID ≥ 1.32), > mean + 1SD (TID ≥ 1.19) and a TID in the group's highest quartile (TID ≥ 1.15). Of the 360 validation group patients, 12 (3.3%), 48 (13.3%) and 70 (19.4%) had TID ≥ 1.32, 1.19 and 1.15, respectively. Age, gender, family history of coronary artery disease (CAD), known CAD, smoking, hypertension, diabetes, dyslipidemia, rest LVEF, post-stress LVEF, ΔLVEF, ≥ 5% or 10% decrease in LVEF did not predict TID ≥ 1.32. However, TID ≥ 1.19 was predicted by rest LVEF and ≥ 5% decrease in LVEF (P = 0.04 and 0.02, respectively) and TID ≥ 1.15 was predicted by ≥ 5% decrease in LVEF (P = 0.02). Cardiac event-free survivals were similar in patients with a TID ≥ and < 1.32 (P = 0.68), ≥ and < 1.19 (P = 0.40) and ≥ and < 1.15 (P = 0.79). CONCLUSIONS Transient ischemic dilatation does not confer adverse prognosis in patients with normal perfusion on adenosine stress/rest 99mTc-sestamibi irrespective of the threshold used for its definition.