Vivid 7 ultrasound machine

Echocardiographic examination was performed using Vivid 7 ultrasound machine (GE Medical System, Horten, Norway). Acquired data were stored digitally and analyzed offline using the EchoPAC software (GE Medical System, Horten, Norway). Average values of echocardiographic indices based on readings from three cardiac cycles were used for statistical analyses.
M-mode echocardiography was performed from the standard parasternal short-axis view for measurement of the following indices: LV end-systolic and end-diastolic dimensions, shortening fraction, septal and LV posterior wall thickness, and LV mass.
From the four-chamber view, pulsed-wave Doppler examination was performed to determine transmitral peak early (E) and late (A) diastolic velocities, E wave deceleration time, and E/A ratio. Colour tissue Doppler imaging of the LV lateral wall was performed with frame rates >100 Hz. With the sample volume positioned at the LV lateral wall-mitral annular junction, the mitral annular peak myocardial velocities at systole (s), early diastole (e), and late diastole (a) were measured and the mitral E/e ratio was also calculated. The relatively load-independent index of ventricular systolic function, myocardial acceleration during isovolumic contraction (IVA), was also measured as reported.[18 (link)]

Blood pressure is measured by tail-cuff using the CODA high throughput non-invasive BP system (Kent Scientific), detailed previously21 (link)58 (link). Briefly, the animal is placed in individual holders at least 10 minutes prior to obtaining pressure measurements. Acclimatization is accomplished through training sessions. BP measurements were taken every two weeks throughout the duration of the survival study (9 months). A minimum of 10 readings were taken, and the mean of acceptable readings (as determined by the software instrument) were recorded per animal, at each observation time.
Echocardiography (ECHO) for non-invasive assessment of cardiac function and structure. Standard ECHO was performed on surviving genotypes at 9 months. All ECHO examinations and analysis were performed by a skilled sonographer (S.H) blinded to treatment, as previously described19 (link)21 (link). Briefly; a Vivid 7 ultrasound machine (General Electric, Waukesha, WI) with a GE Vivid 7 10S transducer was used to collect ECHO data. Images were taken at a depth of 2–2.5 cm of the parasternal short-axis left ventricular view, using the papillary muscles as anatomical landmarks. Images were then exported to a separate workstation for analysis using EchoPAC (General Electric, Waukesha WI).

Echocardiographic acquisitions were made using Vivid 7 ultrasound machine (General Electric, Vingmed, Horten, Norway). Offline analyses of the recordings were performed using EchoPAC software (General Electric, Vingmed, Horten, Norway). Measurements of all echocardiographic parameters were made in three cardiac cycles and the average was taken for statistical analyses.
From the four-chamber view, RV end-diastolic and end-systolic areas were measured and RV fractional area change was calculated accordingly. Transmitral pulsed-wave Doppler examination was performed to obtain peak early diastolic inflow velocity (E), late diastolic inflow velocity (A), E/A ratio, and E deceleration time. Tissue Doppler echocardiography was performed with sample volume positioned at the basal LV free wall-mitral annular junction to obtain the peak early diastolic myocardial tissue velocity (e), late diastolic myocardial tissue velocity (a), e/a ratio, and E/e ratio. Severity of pulmonary regurgitation was graded semi-quantitatively as mild, moderate, or severe by color flow mapping^{18 (link)}.