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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 5, September/October 2017
AFRICA
309
Right ventricular strain as predictor of pulmonary
complications in patients with femur fracture
Hyun-Jin Kim, Hyung-Bok Park, Yongsung Suh, Hyun-Sun Kim, Yoon-Hyeong Cho, Tae-Young Choi,
Eui-Seok Hwang, Deok-Kyu Cho
Abstract
Background:
Following femur fracture, medullary fat enters
the systemic circulation and altered pulmonary haemody-
namics may contribute to pulmonary complications. This
study evaluated the association between right ventricular
(RV) function and pulmonary complications in patients with
femur fracture.
Methods:
Patients with a femur fracture who had undergone
pre-operative echocardiography that included RV peak global
longitudinal strain (RV GLS) were evaluated retrospectively
between March 2015 and February 2016. Pulmonary compli-
cations were defined as the development of pneumonia or
pulmonary thromboembolism during the first postoperative
month.
Results:
Among 78 patients, pulmonary complications devel-
oped in eight (10.3%). The RV GLS value of all patients was
lower than the normal range. In addition, the RV GLS value
of patients with pulmonary complications was significantly
lower than that of patients without pulmonary complica-
tions. Multivariate regression analyses found that worse RV
GLS values independently predicted pulmonary complica-
tions [odds ratio (OR) 2.09, 95% confidence interval (CI)
1.047–4.151,
p
=
0.037]. Receiver operating characteristic
curve analysis found that a RV GLS value of –14.85% was
the best cut-off value to predict pulmonary complications;
sensitivity: 75.0%; specificity: 62.9%. Moreover, patients with
RV GLS values
>
–14.85% had significantly lower pulmonary
complication-free survival.
Conclusions:
In patients with femur fracture, RV GLS values
could help predict pulmonary complications. Therefore,
patients with RV GLS values
>
–14.85 should be monitored
closely before and after surgery for femur fracture.
Keywords:
femur fracture, RV peak global longitudinal strain,
pneumonia, pulmonary thromboembolism
Submitted 22/8/16, accepted 12/1/17
Published online 1/2/17
Cardiovasc J Afr
2017;
28
: 309–314
www.cvja.co.zaDOI: 10.5830/CVJA-2017-011
Following femur fracture, a long-bone trauma, medullary
fat enters the systemic circulation and altered pulmonary
haemodynamics may contribute to pulmonary complications.
1,2
Large amounts of medullary fat emboli entering the systemic
circulation may produce multisystem dysfunction, more serious
conditions, and pulmonary complications.
3
In addition, following
acute trauma, hormonal changes induce triglyceride hydrolysis
and free fatty acid release, causing injury to the pulmonary
capillary endothelium.
4
All these changes after femur fracture,
including altered pulmonary haemodynamics, hormonal changes
and systemic inflammatory reactions, could worsen the clinical
outcome of such patients. Accordingly, hospital stay or outcome
can also be affected, not only by pulmonary complications with
altered pulmonary haemodynamics but also from multisystem
dysfunction.
Pulmonary vascular resistance (PVR) is an important
component of pulmonary haemodynamics and a critical
determinant of right ventricular (RV) systolic function.
5
However, because PVR can only be measured directly by invasive
right heart catheterisation, a non-invasive measurement of
PVR is needed to evaluate acute trauma patients. Research has
demonstrated that RV myocardial strain estimates RV function
accurately and is correlated with the pulmonary haemodynamics
of patients with pulmonary hypertension.
6-8
Consequently, RV
myocardial strain, as a measure of RV function, may provide new
insights into detecting altered pulmonary haemodynamics and
thereby predict pulmonary complications after femur fracture.
The aim of this study was to evaluate the association between
pulmonary complications and RV function in patients with
femur fracture.
Methods
Data from 100 consecutive patients who visited a hospital for
femur fracture between March 2015 and February 2016 and also
underwent transthoracic echocardiography were retrospectively
analysed. Among these, 22 patients were excluded from the study
because the echocardiographic image quality was inadequate for
quantitative analysis.
The study was approved by the institutional review boards of
the hospitals, and was conducted according to the Declaration
Division of Cardiology, Department of Internal Medicine,
Myongji Hospital, South Korea
Hyun-Jin Kim, MD,
titi8th@gmail.comHyung-Bok Park, MD
Yongsung Suh, MD
Yoon-Hyeong Cho, MD
Tae-Young Choi, MD
Eui-Seok Hwang, MD
Deok-Kyu Cho, MD
Department of Translational Medicine, College of Medicine,
Seoul National University, South Korea
Hyun-Jin Kim, MD
College of Nursing and Research Institute of Nursing
Science, Seoul National University, South Korea
Hyun-Sun Kim, MSN, RN