Methods
This cross-sectional study was conducted in National Center for
Cardiovascular Diseases and a university hospital from November 2019 to
January 2020. Seventy-two Patients (mean age: 40.90 ± 13.28), )21
patient :29.1 % male gender) who underwent right heart catheterization
(RHC) were enrolled in this study. This study was approved by the
Ethical Committee of the University of Medical Sciences .
Exclusion criteria were poor image quality, history of liver disease,
tricuspid stenosis, equal or more than moderate TR, pericardial disease
and presence of any type of arrhythmia or heart block. Patients were
divided in two groups with PHTN and with normal PAP .Patients with PHTN
were subdivided in two sub-groups based on the presence or absence of
significant RV dysfunction. Significant RV dysfunction was defined as RV
fraction area change(FAC)<20% and by visual
assessment(10,
11). All patients had LVEF >
50% and were in sinus rhythm.
RHC was performed in the cardiac catheter laboratory under radiographic
guidance (Siemens Medical Solutions, Erlangen, Germany). PHTN was
defined as mPAP greater than or equal to 25 mmHg in RHC
(12).
All subjects underwent transthoracic echocardiography (TTE) using
Phillips iE33 ultrasound device equipped with an S5-1 transducer by an
expert echocardiologist who was blinded to RHC results the day after
RHC. An electrocardiogram and spirogram were recorded during TTE. After
a complete conventional TTE, the spectral Doppler of the MHV was
obtained via subcostal view. A 2-mm Pulse Wave sample volume was placed
1 to 2 cm into the MHV, proximal to its junction with the IVC. Color
Doppler flow was used to obtain good alignment of ultrasound beam to the
MHV flow. The velocity filter was adjusted to optimize the quality of
the spectral display and to allow visualization of low-velocity
waveforms. Data derived from recording of several respiratory cycles
using speed of 25 mm/s. To obtain accurate morphology and measurements
of HV waveform, Doppler data were traced at the speed of 75 mm/s (6,7).
The measured parameters in spectral Doppler of the HV included maximal S
,V ,D and A wave velocities, the systolic velocity time integral (S
VTI), diastolic VTI (D DVTI) and atrial reversal VTI (A AVTI) waves.
Furthermore, time to peak and duration of all the waves were measured
separately. All parameters were obtained in several respiratory cycle
and averaged in five cardiac cycles during end inspiration. Furthermore,
the hepatic venous systolic filling fraction [S/(S+D)], S/D and A/S
ratios were also calculated.