Figures
- Figure 1.
a) Normal parasternal long-axis view. Note that the right ventricle is less than one third of the size of the left ventricle. b) Parasternal long-axis view in pulmonary hypertension (PH). Severely dilated right ventricle with hypertrophy of the moderator band and the right ventricular free wall. The left ventricular cavity is small due to chronic right ventricular pressure overload. c) Normal parasternal long-axis view of the right ventricular outflow tract (RVOT) showing the main pulmonary trunk, branches of the pulmonary artery and the pulmonary valve. d) Parasternal long-axis view of the RVOT in PH showing the dilated pulmonary artery and branches. e) Normal apical four-chamber view. f) Apical four-chamber view in PH showing marked right ventricular dilation and hypertrophy.
- Figure 2.
a) Measurement of the peak tricuspid regurgitant velocity. b) Pulmonary regurgitant velocity at the start of diastole (PRVbd) and end-diastole (PRVed). c) Acceleration time (AT) measured across the pulmonary outflow tract in the parasternal short-axis view. d) Right atrial pressure: M-mode during sniff manoeuvre.
- Figure 3.
a) Measurement of the right atrial a) area and b) long axis for calculation of right atrial volume. c) Measurement of the left ventricular eccentricity index in c) end-diastole and d) end-systole. DI: minor axis perpendicular to the septum; D2: minor axis of the left ventricle parallel to the septum.
- Figure 4.
a) Measurement of myocardial performance index (MPI) using tissue Doppler imaging. S’: systolic wave; IVCT: isovolumic contraction time; IVRT: isovolumic relaxation time. b) Measurement of tricuspid annular plane systolic excursion (TAPSE); ET: ejections time.
- Figure 5.
An algorithm for investigating pulmonary hypertension (PH) using echocardiography. TRV: tricuspid regurgitant velocity; PRV: pulmonary regurgitant velocity; RV: right ventricle; LV left ventricle; PLAX: parasternal long axis; RVOT: right ventricular outflow tract; AT: acceleration time; TAPSE: tricuspid annular plane systolic excursion; IVRT: isovolumic relaxation time; IVC: inferior vena cava; RA: right atrium. #: in patients >60 yrs of age, a TRV ≥2.9 m·s−1 is used as a cut-off value [13].
Tables
- Table 1. Parameters affected by pulmonary hypertension (PH) that can be detected by right heart imaging
View Measurements Normal range PH Long-axis view of LV or short-axis view of aorta and left atrium LV end-diastolic diameter cm 4.2–5.9 in males and 3.9–5.3 in females [8–10] ↓ LV end-systolic diameter cm 2.1–4.0 in males and 2.4 in females [8–10] ↓ Long-axis view of the RV inflow tract Basal diameter of RV cm 3.7–5.4 [11] ↑ Tricuspid annulus cm 1.3–2.8 [11, 12] ↑ Tricuspid regurgitant velocity m·s−1 <2.6 [13] ↑ Long- and short-axis views of RVOT or short-axis view of aorta and left atrium RVOT cm 1.7–2.3 [8, 11] ↑ Main pulmonary trunk cm 1.5–2.1 [8, 11] ↑ Right pulmonary artery cm 0.7–1.7 [11, 14] ↑ Left pulmonary artery cm 0.6–1.4 [8, 11] ↑ RV outflow acceleration time ms >110 [8, 15, 16] ↓ Pulmonary regurgitant velocity (beginning of diastole) m·s−1 <1 [14, 17] ↑ Pulmonary regurgitant velocity (end diastole) m·s−1 <1 [14, 17] ↑ Apical four-chamber view# Basal diameter of RV cm 2.0–2.8 [8, 11] ↑ RV end-diastolic area cm2 11–28 [8, 11] ↑ RV end-systolic area cm2 7.5–16 [8, 11, 18] ↑ Right atrial area (end-systole) cm2 13.5±2 cm [18] ↑ RA volume index mL·m−2 ≤34 in males and ≤27 in females [8, 19, 20] ↑ Tricuspid annulus cm 1.3–2.8 [8, 12] ↑ Right ventricular fractional area change % 32–60 [8, 21, 22] ↓ Apical four-chamber view¶ Tricuspid regurgitant velocity m·s−1 <2.6 [13] ↑ Deceleration time–tricuspid inflow ms 144–244 [23, 24] ↑ RV MPI (Tei index) <0.28 [8, 25, 26, 27] ↑ TAPSE mm ≥20 [8, 28–30] ↓ IVRT (TDI RV free wall) ms <75 [6, 8, 31, 32] ↑ LV: left ventricle; RV: right ventricle; RVOT: right ventricular outflow tract; RA: right atrium; MPI: myocardial performance index; TAPSE: tricuspid annular plane systolic excursion; IVRT: isovolumic relaxation time; TDI: tissue Doppler imaging; ↓: decreased in PH; ↑: increased in PH. #: two-dimensional echocardiograph; ¶: Doppler echocardiograph.
- Table 2. Effect of pulmonary hypertension (PH) on measurements from tissue Doppler imaging
Measurements [Ref.] Normal S' wave cm·s−1 PH Normal E' cm·s−1 PH Normal A' cm·s−1 PH RV free (lateral) wall [33–35] 12–20 ↓ 10.2–16.2 ↓ 6.2–10.9 ↓ LV septal wall [34] 8.1–10.9 ↔ 9.8–16.0 ↔ 9.0–13.2 ↔ LV lateral wall [34] 9.1–12.9 ↔ 12.5–20.5 ↔ 8.6–14.4 ↔ S': systolic wave; A': late (atrial systole) myocardial diastolic wave; E': early myocardial diastolic wave; RV: right ventricle; LV: left ventricle; ↓: decreased in PH; ↔: no change.
- Table 3. Estimation of right atrial pressure from the inferior vena cava [8]
Inferior vena cava diameter Change with respiration Estimated right atrial pressure mmHg Small <1.5 cm Collapse 0 Normal 1.5–2.5 cm Decrease by >50% 5 Normal Decrease by <50% 10 Dilated >2.5 cm Decrease by <50% 15 Dilated with dilated hepatic veins No change 20 - Table 4. Right ventricular pressure, cavity and functional measurements that may indicate pulmonary hypertension
Parameter [Ref.] Normal Intermediate Abnormal Pra mmHg [8] <5 5–10 >10 TRV m·s−1 [13] <2.6 ≥2.6
≥2.8 in obese subjects
≥2.9 in patients >60 yrsRVSP mmHg [13] <37 ≥37
≥40 in obese subjects
≥44 in patients >60 yrsRVOT acceleration time ms [8, 15, 16] >110 105–110 <105 RA volume index mL·m−2 [8] ≤34 in males and ≤27 in females >34 in males
>27 in femalesRV fractional area change % [8, 21, 22] 32–60 ≤32 LV eccentricity index [8, 44, 45] 1 >1 at end-diastole indicates volume loading of the RV
>1 at end-systole indicates pressure loading of the RVRV MPI (Tei index) [8, 25–27] <0.28 0.28–0.32 >0.32 S' wave of tricuspid annulus cm·s−1 [33, 35] >12 11.5–12 <11.5 IVRT s [6, 8, 31, 32] <75 ≥75 TAPSE ms [8, 28–30] ≥20 16–20 <16 Estimated PVR Wood units [46, 47] <1 1–3 >3 Pra: right atrial pressure; TRV: tricuspid regurgitant velocity; RVSP: right ventricular systolic pressure; RVOT: right ventricular outflow tract; RA: right atrium; RV: right ventricle; LV: left ventricle; MPI: myocardial performance index; S' wave: systolic wave; IVRT: isovolumic relaxation time; TAPSE: tricuspid annular plane systolic exertion; PVR: pulmonary vascular resistance.
