S5 1 probe

Transthoracic echocardiography (TTE) was performed with a Philips EPIQ7c ultrasonic diagnostic instrument, S5-1 probe and probe frequency 1–5 MHz. Parameters such as left ventricular ejection fraction (measured by the biplane Simpson's method) were recorded in detail in the left recumbent position. TEE was examined by PhilipsiE33 color Doppler ultrasonography with an X7-2t transesophageal matrix real-time three-dimensional probe with a frequency of 2–7 MHz. Before fasting for 6–8 h, the ECG was recorded synchronously, the pulsed Doppler sampling volume was placed within 1 pulse near the opening of the left atrial appendage, and the blood flow spectrum of the left atrial appendage was obtained. The left atrial appendage blood flow spectrum was a regular two-way wave in sinus rhythm and an irregular zigzag waveform in atrial fibrillation rhythm. The peak value of the positive wave, that is, the maximum emptying velocity of the left atrial appendage, was recorded in 3 and 10 cardiac cycles, respectively, and the average value was taken as the velocity of the left atrial appendage (LAA-FV) (Fig. 1–2).Figure 1

The blood flow pattern of the left atrial appendage in sinus rhythm.

Figure 2

The blood flow pattern of the left atrial appendage in atrial fibrillation rhythm.

A Philips EPIQ7 echocardiograph equipped with an S5-1 probe (frequency 1–5 MHz) and frame rate ≥60 beats/min was used. When performing echocardiography, patients should remain in the left lateral position and maintain calm breathing. A synchronized electrocardiogram was connected to an ultrasound machine. The left ventricular end diastolic diameter (LVDd), left ventricular end systolic diameter (LVDs), interventricular septum diameter (IVSd) and left ventricular posterior wall diameter (LVPWd) were measured in each patient, representing the end-diastolic/systolic anteroposterior diameter of left ventricular, left ventricular end-diastolic septal thickness, and left ventricular end-diastolic posterior wall thickness, respectively. The ratio of E/A and E/e' were used to estimate LV diastolic function, where E and A are early and late transmitral flow velocities, and e' is early diastolic septal tissue velocity. Left ventricular ejection fraction (LVEF) was measured using the modified Simpson biplane method.

A Philips EPIQ 7c ultrasonic diagnostic apparatus, S5-1 probe, and probe with a frequency 1–5 MHz were used. The patient was placed in the left decubitus position, and the patient’s left atrium anteroposterior diameter, left ventricular end-diastolic diameter, left ventricular ejection fraction (measured by biplane Simpson method), left ventricular posterior wall thickness, ventricular septal thickness and other parameters were recorded in detail. The Devereux formula [14 (link)] was used to calculate the left ventricular mass index (LVMI), as follows: LVMI (g/m²) = LVM (calculated by 0.8 × 1.04 [(IVSd + PWTd + LVDd)³ − LVDd³] + 0.6)/BSA (calculated by 0.006 × height (cm) + 0.013 × body weight (kg) − 0.153).

A PhilipsEPIQ7C diasonograph (Philips, Amsterdam, the Netherlands) was used with a C5-1 probe of frequency 1 to 5 MHz and an S5-1 probe of frequency 1 to 5 MHz. A GE VolusonE10 diasonograph (GE, Tiefenbach, Austria), C5-1 probe with frequency 1 to 5 MHz, and C9-2 probe with frequency 2 to 9 MHz were used for the following: (1) routine fetal ultrasound examination excluding malformations and verified fetal gestational age; (2) fetal echocardiography excluding structural abnormalities in the fetal heart; (3) measurement of the TAPSE value, showing the standard four-chambered heart. The position of the probe was adjusted to move the tip forward or backward, the M-type ultrasound mode was initiated, the sampling line was placed at the tangent position at the junction of the anterior lobe ring and the right ventricular free wall, the angle of the longitudinal movement was adjusted to < 15°, and the distance from the lowest point of movement to the highest was measured (Figs. 1A, 1B); (4) tissue doppler imaging (TDI) was obtained by the tricuspid ring movement spectrum of the mitral lobe at the anterior lobe and the valve ring junction. The scan speed was adjusted to the maximum, and the Tei index was measured (Figs. 2A, 2B). All data were measured for the three stable cardiac cycles, and the averages were recorded.

A Philips IE Elite ultrasound diagnostic instrument with an S5-1 probe at 2.5 to 3.5 MHz was used in this study, and the data analysis was completed using offline Q-Lab 9.0 software. The ultrasound contrast agent used was SonoVue (Bracco, Italy).