Impaired coronary blood flow in patients with metabolic syndrome: documented by Thrombolysis in Myocardial Infarction (TIMI) frame count method

Background

Endothelium plays an important role in regulating coronary vascular tone. In addition, several of cardiovascular risk factors that are associated metabolic syndrome have been reported to be associated with endothelial dysfunction. In the present study we aimed to evaluate the coronary blood flow in patients with metabolic syndrome by means of the Thrombolysis in Myocardial Infarction (TIMI) frame count.

Method

Forty-two patients with metabolic syndrome (group I) and 42 control subjects without metabolic syndrome (group II) were included in the study. All subjects had angiographically proven normal coronary arteries. Diagnosis of metabolic syndrome was based on the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) guidelines published in 2001. Coronary flow rates of all subjects were documented by TIMI frame count method.

Results

TIMI frame counts for each of the major epicardial coronary arteries were found to be significantly higher in patients with metabolic syndrome compared with control subjects (corrected TIMI frame count for left anterior descending coronary artery: 35 ± 7 vs 25 ± 7, respectively; left circumflex coronary artery: 32 ± 9 vs 25 ± 7, respectively; right coronary artery: 31 ± 9 vs 24 ± 5, respectively; P < .001 for all). Statistically significant independent relationships were found between TIMI frame count and body mass index (R² = 0.480, P = .009), waist circumference (R² = 0.551, P = .001), and triglyceride level (R² = 0.434, P = .036).

Conclusion

We have shown for the first time that patients with metabolic syndrome and angiographically normal coronary arteries have higher TIMI frame counts for all 3 coronary vessels, indicating impaired coronary blood flow, compared to control subjects without metabolic syndrome.