Evaluation of the effect of trimetazidine on Tc-99m methoxyisobutyl isonitrile gated scintigraphy in patients with coronary artery ectasia

OBJECTIVE: Coronary artery ectasia (CAE) is the abnormal dilatation of a segment of the coronary artery to a diameter of at least 1.5 times that of normal adjacent segments. Symptoms are variable, and its prognosis and treatment modalities are unclear. The aim of this study is to evaluate the effect of trimetazidine (TMZ) on ischemic left ventricular function by rest-stress Tc-99m methoxyisobutyl isonitrile (Tc-99m MIBI) myocardial scintigraphy in symptomatic patients with CAE.

METHODS: We included patients with ectasia admitted to our Cardiology Department, Turkey, between 2003 and 2004 in this study. All patients underwent coronary angiography and diagnosed with CAE, before and 4 weeks after TMZ administration. Seventeen patients (9 men, 8 women) underwent gated single-proton emission tomographic (SPECT) using Tc-99m MIBI. We performed quantitative global and regional ventricular functional analysis using quantitative gated SPECT software.

RESULTS: The global ejection fraction increased from 59.9%±8.9% to 62.6%±8.3% after therapy (p=0.033). In addition, the end systolic volume and the end diastolic volume decreased after therapy (101.7±23.5 ml to 95.1±22.9 ml, p=0.002; from 41.1±14.3 to 36.4±13.6, p=002). In all segments, we observed significant post-therapy increases in relative tracer uptake. Percentage of MIBI uptake was 71.2±15.3 at baseline stress and 73.2±15 post-TMZ (p=0.001). As global function parameters, the total wall motion normal areas changed significantly (67-74% p=0.01) after therapy, but the total wall thickness did not changed significantly(49-45%, p=0.21).

CONCLUSION: The results of this study demonstrate that TMZ improves myocardial function by rest-stress Tc-99m MIBI gated SPECT during stress-induced ischemia in patients with CAE. Also, the outcomes revealed improvement in functional parameters, and percentage of MIBI uptake post TMZ administration. We can use this procedure to monitor the effect of TMZ in CAE patients.