Overweight causes left ventricular diastolic asynchrony and diastolic dysfunction: a study based on speckle tracking echocardiography in healthy subjects.
BACKGROUND
Left ventricular (LV) diastolic dysfunction is often observed in healthy subjects and can be a cause of heart failure with preserved ejection fraction (EF). We aimed to investigate the role of LV diastolic asynchrony as a cause of diastolic dysfunction in healthy subjects.


METHODS
In 40 healthy subjects, two-dimensional speckle tracking imaging (2DSTI) was performed to measure the peak early diastolic longitudinal strain rates (Esr) of the apical, mid-ventricular, and basal segments of the septum and posterior wall. A mean value of the Esr of the 6 segments (mEsr) was calculated. The time from aortic valve closure to the Esr was measured for each segment, and the standard deviation (SDTEsr) was calculated. The peak global early diastolic strain rate (gEsr) was measured with a region of interest (ROI) on the whole LV myocardium. LV flow propagation velocity (FPV) was measured using conventional Doppler techniques.


RESULTS
SDTEsr was not correlated with age, but was significantly correlated with body mass index (BMI) (r = 0.41, p < 0.01). Although no significant correlation was observed between mEsr and FPV, gEsr and SDTEsr significantly correlated with FPV (r = 0.41, p < 0.01; r = -0.54, p < 0.001). As a result of the multiple regression analysis, SDTEsr was the single determinant of FPV.


CONCLUSIONS
Diastolic asynchrony, associated with overweight but not with aging, may contribute to diastolic dysfunction in healthy subjects.
Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan.
Masahiro
M
Nakabachi
Faculty of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo, 060-0812, Japan. mikami@hs.hokudai.ac.jp.
Taisei
T
Mikami
Graduate School of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo, 060-0812, Japan.
Kazunori
K
Okada
Faculty of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo, 060-0812, Japan.
Hisao
H
Onozuka
Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan.
Sanae
S
Kaga
Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan.
Mamiko
M
Inoue
Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan.
Shinobu
S
Yokoyama
Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan.
Mutsumi
M
Nishida
Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan.
Chikara
C
Shimizu
Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan.
Kazuhiko
K
Matsuno
Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.
Hiroyuki
H
Iwano
Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.
Satoshi
S
Yamada
Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.
Hiroyuki
H
Tsutsui
Diastolic asynchrony; Left ventricular diastolic function; Overweight; Two-dimensional speckle tracking imaging