Regional myocardial motion in patients with mild cognitive impairment: a pilot study

Background: Cardiovascular disease (CVD) is a risk factor for cognitive impairment in the elderly. Manifestations of subclinical CVDs can be found in patients with cognitive impairment. The aim of the present study was to test the hypothesis that patients with mild cognitive impairment (MCI) have different magnetic resonance imaging (MRI)-derived regional myocardial motion indices compared with healthy controls. Methods: Eleven MCI patients (age, 65.5 years +/- 5.9; range, 55-81 years old) and 11 sex-/age-matched healthy volunteers were enrolled. All of the participants underwent a head MRI and cardiac MRI. Global cortical atrophy (GCA) was graded on the head MRI. The left ventricular ejection fraction (LVEF) and regional strain, strain rate, displacement and velocity were measured on cine images. The GCA scores, global cardiac function and regional myocardial motion indices were compared between MCI patients and healthy controls using the t-test. Results: MCI patients had a higher GCA score than healthy controls (p = 0.048). However, there was no significant difference in LVEF between MCI patients and controls. Compared to healthy controls, MCI patients had a lower peak radial strain (29.1% +/- 24.1% vs. 46.4% +/- 43.4%, p < 0.001), lower peak diastolic radial strain rate (3.2 +/- 2.4 s(-1) vs. 6.0 +/- 3.0 s(-1), p < 0.001), lower peak diastolic circumferential strain rate (2.5 +/- 2.1 s(-1) vs. 3.2 +/- 2.1 s(-1), p = 0.002), lower peak systolic radial displacement (4.2 +/- 2.2 mm vs. 5.2 +/- 3.3 mm, p = 0.002), lower peak diastolic radial velocity (31 +/- 18 mm/s vs. 45 +/- 33 mm/s, p < 0.001), and lower peak diastolic circumferential velocity (178 +/- 124 degree/s vs. 217 +/- 131 degree/s, p = 0.005). Conclusion: MRI-derived regional myocardial strain, strain rate and velocity were found to be different between MCI patients and healthy controls. Regional myocardial motion indices have the potential to become novel quantitative imaging biomarkers for representing the risk of neurodegenerative disorders, such as Alzheimer's disease (AD).