Changes in Left Ventricular Function Assessed by 3D Echocardiography During Severe Central Hypovolemia in Healthy Humans
Kazukuni Hirabuki
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorNoritaka Hata
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorMarina Fukuie
The National Institute of Advanced Industrial Science and Technology, Mitaka City, Tokyo, Japan
Search for more papers by this authorRina Suzuki
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorTomoya Suda
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorTakahiro Uechi
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorAi Hirasawa
Department of Health and Welfare, Faculty of Health Sciences, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorJun Sugawara
The National Institute of Advanced Industrial Science and Technology, Mitaka City, Tokyo, Japan
Search for more papers by this authorTakeaki Matsuda
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorCorresponding Author
Shigeki Shibata
Department of Physical Therapy, Faculty of Health Science, Kyorin University, Mitaka City, Tokyo, Japan
Correspondence: Shigeki Shibata ([email protected])
Search for more papers by this authorKazukuni Hirabuki
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorNoritaka Hata
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorMarina Fukuie
The National Institute of Advanced Industrial Science and Technology, Mitaka City, Tokyo, Japan
Search for more papers by this authorRina Suzuki
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorTomoya Suda
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorTakahiro Uechi
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorAi Hirasawa
Department of Health and Welfare, Faculty of Health Sciences, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorJun Sugawara
The National Institute of Advanced Industrial Science and Technology, Mitaka City, Tokyo, Japan
Search for more papers by this authorTakeaki Matsuda
Department of General Medicine, Faculty of Medicine, Kyorin University, Mitaka City, Tokyo, Japan
Search for more papers by this authorCorresponding Author
Shigeki Shibata
Department of Physical Therapy, Faculty of Health Science, Kyorin University, Mitaka City, Tokyo, Japan
Correspondence: Shigeki Shibata ([email protected])
Search for more papers by this authorFunding: This study was supported in part by the Japan Society for the Promotion of Science (17K19949; Jun Sugawara, 19K19984; Kazukuni Hirabuki).
ABSTRACT
Purpose
Central hypovolemia is considered to lead to a compensatory increase in cardiac contractility. From a physiological perspective, left ventricular (LV) twisting motion, which plays an important role in maintaining cardiac output, should be enhanced during central hypovolemia, but previous studies have shown inconsistent findings. Using 3D echocardiography, we tested the hypothesis that the LV twisting and untwisting motion would be enhanced during severe central hypovolemia.
Methods
Thirteen healthy men (25 ± 5 years old) underwent the maximal lower body negative pressure (LBNP) protocol; graded increase in LBNP loads up to presyncope. We evaluated the basic hemodynamics and LV function with 3D and Doppler echocardiography at each stage of LBNP. Indices were compared among baseline, half maximal LBNP (LBNP1/2max), and one stage before the presyncope (LBNPpre-max) to consider individual differences in orthostatic tolerance.
Results
In response to LBNP, ejection fraction (baseline: 62 ± 3, LBNP1/2max: 55 ± 5, LBNPpre-max: 43% ± 9%, mean ± SD, p < 0.01, ANOVA), global longitudinal strain (−20.5 ± 2.8, −17.6 ± 2.7, −13.6% ± 4.7%, p < 0.01), and global circumferential strain (−31.2 ± 3.7, −26.8 ± 3.3, −19.4% ± 5.3%, p < 0.01) were weakened. Twist (15.2 ± 5.1, 14.5 ± 5.4, 20.9° ± 7.7°, p = 0.012) and peak untwisting rate (−138 ± 42, −164 ± 50, −245°/cm ± 88°/cm, p < 0.01) were strengthened at the LBNPpre-max. e’ (14.1 ± 2.0, 11.1 ± 1.5, 8.2° ± 2.2 cm/s, p < 0.01) decreased in response to LBNP, while E/e’ (5.8 ± 0.8, 5.4 ± 1.0, 7.8 ± 2.3, p < 0.01) increased at LBNPpre-max.
Conclusion
The present findings indicate that LV twisting motion is enhanced during severe central hypovolemia. On the other hand, conventional echocardiographic indices appeared to deteriorate. Intriguingly, an index of LV filling (E/e’) was paradoxically enhanced during severe central hypovolemia.
Conflicts of Interest
The authors declare no conflicts of interest.
Open Research
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.
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