Simple prediction of right ventricular ejection fraction using tricuspid annular plane systolic excursion in pulmonary hypertension

The present study examined whether tricuspid annular plane systolic excursion (TAPSE) can simply predict right ventricular ejection fraction (RVEF) in patients with pulmonary hypertension (PH). The TAPSE cut-off value to predict reduced RVEF was also evaluated. The association between TAPSE and cardiac magnetic resonance imaging (CMRI)-derived RVEF was examined in 53 PH patients. The accuracy of the prediction equation to calculate RVEF using TAPSE was also evaluated. In PH patients, TAPSE was strongly correlated with CMRI-derived RVEF in PH patients (r = 0.86, p < 0.0001). We then examined the accuracy of the two equations: the original regression equation (RVEF = 2.01 × TAPSE + 0.6) and the simplified prediction equation (RVEF = 2 × TAPSE). Bland–Altman plot showed that the mean difference ± limits of agreement was 0.0 ± 10.6 for the original equation and ?0.6 ± 10.6 for the simplified equation. Intraclass correlation coefficient was 0.84 for the original and 0.82 for the simplified equation. Normal RVEF was considered to be ≥40 % based on the data from 53 matched controls, and the best TAPSE cut-off value to determine reduced RVEF (<40 %) was calculated to be 19.7 mm (sensitivity 88.9 %, specificity 84.6 %). A simple equation of RVEF = 2 × TAPSE enables easy prediction of RVEF using TAPSE, an easily measurable M-mode index of echocardiography. TAPSE of 19.7 mm predicts reduced RVEF in PH patients with clinically acceptable sensitivity and specificity.     

Pimobendan improves right ventricular myocardial contraction and attenuates pulmonary arterial hypertension in rats with monocrotaline-induced pulmonary arterial hypertension

Purpose

The present study aimed to evaluate the therapeutic effect of pimobendan treatment for pulmonary hypertension (PH) in rats administered monocrotaline (MCT).

Methods

Fifty-four 12-week-old male Sprague–Dawley rats were injected with monocrotaline or saline solution. Serial echocardiography and right ventricular systolic pressure (RVSP) measurement via a cardiac catheter were performed. After injection of MCT, rats received oral pimobendan (MCT/pimobendan group) or no treatment (MCT group) until undergoing echocardiography and cardiac catheter insertion.

Results

Right ventricular systolic pressure in the MCT/pimobendan group was lower than that in the MCT group at 6 weeks. Right ventricle free wall (RVFW) myocardial systolic velocity (Sm) in the MCT group showed a reduction compared with the saline group at 2 weeks. RVFW Sm in the MCT/pimobendan group was preserved as compared with the saline group at 2 weeks. RVFW Tei index in the MCT/pimobendan group showed a reduction compared with the saline group and the MCT group at 2 weeks. Echocardiography in the MCT/pimobendan group showed improvement compared with MCT rats.

Conclusions

Both a reduction in RVSP and improvement in myocardial contraction were demonstrated with administration of pimobendan in rats with PH induced by MCT. Echocardiography evaluation of systolic function seems to be useful for monitoring excess administration of pimobendan.     

Simultaneous assessment of right ventricular ejection fraction and central haemodynamics at rest and during exercise in patients with pulmonary hypertension

Summary. In 10 patients, aged 55–73, with pulmonary hypertension, right ventricular ejection fraction (RVEF) was measured simultaneously with central haemodynamics twice, at rest and during exercise. In the first investigation, RVEF was measured with first pass (FQ) radionuclide angiocardiography using ¹³³Xe and ⁹⁹Tc^m as tracers. In the second investigation after 1 h's rest, RVEF was measured with equilibrium (EQ) radionuclide angiocardiography. Significant correlations were found between RVEF and pulmonary artery pressure (r = - 0. 76 to - 0. 88) and between RVEF and right arterial pressure (r= -0. 76 to -0. 84) at rest and during exercise. RVEF was low or decreased during exercise in all patients with haemodynamic signs of right ventricular failure. Good correlations were found between the FP and EQ techniques for measuring RVEF both at rest, r= 0.86, and during exercise, r= 0.91. RVEF, measured with the FP technique, showed better reproducibility and better correlation to haemodynamic variables and to history of right ventricular failure than the EQ technique. Thus, the FP technique seemed to be the method of choice for assessment of RVEF.     

二维斑点追踪成像对肺动脉高压患者右室长轴收缩功能的诊断价值

目的探讨二维斑点追踪成像(2D-STI)对肺动脉高压(PH)患者右室长轴收缩功能的临床应用价值。方法 45例PH患者(PH组)和30例体检健康者(对照组)使用2D-STI对其行心尖四腔心切面探查,获取右室游离壁及室间隔长轴6节段的收缩期峰值应变(PSS)及收缩期峰值应变达峰时间(PSST)。结果 PH组右室游离壁的基底段、中间段、心尖段及室间隔中间段、心尖段PSS均小于对照组(均P0.05),而两组室间隔基底段的PSS差异无统计学意义。PH组右室长轴PSST为(73.22±37.64)ms,较对照组(38.13±17.12)ms延长(P0.05)。结论 2D-STI技术可准确评估右室整体及节段收缩功能及同步性,是评价右室功能简便、快捷的新方法。     

Diagnostic and prognostic value of right ventricular strain in patients with pulmonary arterial hypertension and relatively preserved functional capacity studied with echocardiography and magnetic resonance

Right ventricular (RV) dysfunction harbingers adverse prognosis in pulmonary arterial hypertension (PAH). Although conventional two-dimensional echocardiography (2DE) is limited for RV systolic function quantitation, RV strain can be a useful tool. The diagnostic and prognostic impact of 2DE speckle-tracking RV longitudinal strain was evaluated, including other 2DE systolic indexes, in a group of PAH patients without severe impairment of functional capacity, chronic pulmonary thromboembolism or left ventricular dysfunction. Sixty-six group I PAH patients, 67?% NYHA functional class I or II (none in IV) were studied by 2DE to obtain: RV fractional area change, tricuspid annular plane systolic excursion, RV myocardial performance index, tissue Doppler tricuspid annulus systolic velocity. Global, free wall (RVFreeWSt) and septal RV longitudinal systolic strain were obtained. RV ejection fraction by cardiac magnetic resonance (CMR-RVEF) was also assessed. All patients were followed up to 3.9 years (mean 3.3 years). Combined endpoints were hospitalization for worsening PAH or cardiovascular death. Among all the 2DE indexes of RV systolic function, RVFreeWSt exhibited the best correlation with CMR-RVEF (r = 0.83; p?<?0.005). Combined endpoints occurred in 15 (22.7?%) patients (6 hospitalizations and 9 deaths). Multivariate analysis identified RVFreeWSt ≤?14?% as the only 2DE independent variable associated with combined endpoints [HR 4.66 (1.25–17.37); p?<?0.05]. We conclude that RVFreeWSt may be a suitable non-geometric 2DE surrogate of CMR-RVEF in PAH patients, constituting a powerful independent predictor of long-term outcome in this cohort with relatively preserved functional capacity.     

Prognostic value of right ventricular free wall strain in pulmonary hypertension patients with pseudo-normalized tricuspid annular plane systolic excursion values

Pulmonary hypertension (PH) is a progressively fatal disease having a significant impact on right ventricular (RV) function, a major determinant of long-term outcome in PH patients. In our clinic we frequently noticed the combination of PH and reduced RV function, but with discordant Tricuspid Annular Plane Systolic Excursion (TAPSE) values. The present study focuses on whether RV free wall strain measured using 2-dimensional speckle-tracking echocardiography is able to predict mortality in this subgroup of PH patients. 57 patients with PH and RV dysfunction (visual echocardiographic assessment of ≥2) and pseudo-normalized TAPSE values (defined as ≥16 mm) were retrospectively evaluated. Patients were divided by RV free ?20 % as cut-off value. Follow-up data on all-cause mortality were registered after a median follow-up time of 27.9 ± 1.7 months. RV free of ≥?20 % was predictive of all-cause mortality after a median follow-up time of 27.9 ± 1.7 months (HR 3.76, 95 % CI 1.02–13.92, p = 0.05). RV free ≥?20 % remained a significant predictor of all-cause mortality (HR 4.30, 95 % CI 1.11–16.61, p = 0.04) after adjusting for PH-specific treatment. On the contrary, TAPSE was not a significant predictor of all-cause mortality. RV free wall strain provides prognostic information in patients with PH and RV dysfunction, but with normal TAPSE values. Future studies with larger cohorts, longer follow-up periods and inclusion of more echocardiographic parameters measuring LV and RV function could confirm the strength of RV free ≥?20 % as a predictor of mortality for this subgroup of patients with PH.     

超声Tei指数联合三尖瓣环收缩期位移评价肺动脉高压患儿右心室功能

目的探讨超声Tei指数联合三尖瓣环收缩期位移评价肺动脉高压患儿右心室功能的价值。方法 55例肺动脉高压患儿按肺动脉收缩压程度分为肺动脉高压轻度、中度和重度3组,选取同期门诊体检健康儿童25例作对照组,应用超声心动图分别测量各组右心室Tei指数和三尖瓣环收缩期位移。比较各组间差异,并应用相关分析肺动脉高压患儿三尖瓣环收缩期位移与肺动脉收缩压的关系。结果肺动脉高压中度组右心室Tei指数(0.60±0.09)、重度组右心室Tei指数(0.78±0.11)均明显高于正常对照组(0.37±0.08),重度组右心室Tei指数大于中度组,差异均具有统计学意义(P<0.05),轻度组(0.48±0.06)和正常对照组间差异无统计学意义(P>0.05)。肺动脉高压中度组右心室游离壁[(16.4±4.3)mm]、室间隔三尖瓣环收缩期位移[(8.3±2.3)mm]、重度组右心室游离壁[(13.2±4.6)mm]、室间隔三尖瓣环收缩期位移[(6.4±1.9)mm]均明显低于正常对照组[(23.5±3.4)mm、(10.2±2.1)mm],重度组低于中度组,差异均具有统计学意义(P<0.05),轻度组右心室游离壁[(20.8±4.1)mm]、室间隔三尖瓣环收缩期位移[(11.4±2.6)mm]和正常对照组间差异无统计学意义(P>0.05)。肺动脉高压患儿三尖瓣环收缩期位移与肺动脉收缩压呈显著负相关。结论超声Tei指数联合三尖瓣环收缩期位移能较好评价肺动脉高压患儿右心室功能。     

多普勒超声联合指标在肾动脉狭窄诊断中的应用

目的探讨多普勒超声指标联合应用在肾动脉狭窄(RAS)诊断中的应用。方法对234例RAS患者采用多普勒超声测量用于诊断RAS的相关超声指标,包括肾动脉峰值流速(RPSV)、肾动脉与腹主动脉收缩期峰值流速比值(RAR)、肾动脉与叶间动脉峰值流速比值(RIR)以及肾内叶间动脉收缩早期加速时间(AT)、收缩早期加速度(AC)、阻力指数(RI),随后行血管造影检查。肾动脉造影显示肾动脉内径减少≥60%患者确定为RAS。使用ROC曲线计算每一项指标最佳阈值的诊断敏感性、特异性和准确性,同时计算两项和3项联合指标的诊断效率。结果在血管造影和多普勒超声显示的422条肾动脉中,血管造影显示185条RAS(肾动脉内径减少60%～99%)和19条闭塞。采用RPSV170cm/s或AT≥0.07s作为联合诊断标准,获得敏感性95.1%,特异性87.2%,准确性90.8%,较任何单一指标的诊断效果均有所提高。而采用RPSV170cm/s、RIR5.6和AT≥0.07s作为联合诊断指标,虽诊断敏感性提高了1.7%,但特异性下降了3.7%。结论对于诊断肾动脉内径减少≥60%的RAS,RPSV和RIR是较好的单一多普勒指标。RPSV和AT联合应用可获得最佳的诊断准确率,具有一定的临床应用价值。     

Cardiac magnetic resonance-derived right ventricular outflow tract systolic flow acceleration: a novel index of right ventricular function and prognosis in patients with pulmonary arterial hypertension

To validate the right ventricular outflow tract systolic flow acceleration (RVOT_ACC; peak flow velocity/time-to-peak velocity) measured by phase-contrast (PC)—cardiovascular magnetic resonance (CMR) as a novel index of right ventricular (RV) function, and to investigate its clinical implications in patients with pulmonary arterial hypertension (PAH). Thirty (38 % male, 43 ± 15 years old) out of 55 consecutive patients who were initially diagnosed with PAH at the referral center were prospectively enrolled between March 2009 and July 2010 and were followed for PAH-related cardiovascular events for 2 years. The invasively measured maximum dP/dt (dP/dt_max) was used as an index of RV contractility. The PC-CMR-derived RVOT_ACC was compared with well-known prognostic parameters. The PC-CMR-derived RVOT_ACC correlated strongly with the dP/dt_max and estimated RV function more accurately than the CMR-derived RV ejection fraction. The CMR-derived RVOT_ACC level (HR = 0.87, 95 % CI 0.78–0.98, p = 0.038) could be another powerful prognostic index compared with the functional capacity (hazard ratio [HR] = 0.88, 95 % confidence interval [CI] 0.78–0.97, p = 0.035) and REVEAL Registry risk score (HR = 0.83, CI 0.56–0.95, p = 0.012). Furthermore, receiver-operating characteristic analysis identified ≥0.4 m/s² as the optimal RVOT_ACC cut-off for predicting subsequent cardiovascular events. PC-CMR-derived RVOT_ACC is a promising non-invasively measured index of RV function and prognosis in patients with PAH.     

呼吸对右心衰竭患者三尖瓣反流速度和肺动脉压测定的影响

目的 探讨平静呼吸对右心衰竭患者三尖瓣反流速度和肺动脉收缩压测定的影响.方法 选取32例右心衰竭患者(病例组)和28例右心功能正常而三尖瓣反流患者(对照组)行超声心动图检查.观测三尖瓣反流速度,根据反流法计算肺动脉收缩压,比较两组吸气相与呼气相之间的差异.结果 病例组三尖瓣反流速度、肺动脉收缩压吸气相均小于呼气相(P＜0.001);对照组三尖瓣反流速度、肺动脉收缩压吸气相与呼气相比较差异无统计学意义.结论 使用超声心动图估测肺动脉收缩压时,应注意平静呼吸对右心衰竭患者三尖瓣反流速度和肺动脉收缩压测定的影响,尽量在呼气末或呼气末屏气状态下进行.     

The challenge of endocardial right ventricular pacing in patients with a tricuspid annuloplasty ring and severe tricuspid regurgitation

On occasion, patients with a tricuspid annuloplasty ring may require permanent cardiac pacing. Although it is technically possible to pass a ventricular transvenous lead through a tricuspid valve with an annuloplasty ring, the procedure is complicated by considerable chamber enlargement and mechanical distortion of the tricuspid valve often with severe residual tricuspid regurgitation. Over a 25-month period, transvenous ventricular lead placement following insertion of a tricuspid annuloplasty ring was successfully performed in five patients (three women). The patient mean age was 66 years (range 55-77 years). Four cases had slow atrial fibrillation and another paroxysmal atrial fibrillation requiring His-bundle ablation. Two patients had mitral valve replacement and two aortic and mitral valve replacements. All patients had residual severe to torrential tricuspid regurgitation. Seven ventricular steroid-eluting screw-in leads were used. Single leads were used in three cases, whereas in two others, two ventricular leads were attached to a dual chamber pulse generator. Although technically difficult, ventricular lead placement was successful using standard guidewires with broad curvatures. Satisfactory acute and follow-up stimulation thresholds and sensing were obtained with the only complication being an intraoperative lead dislodgement, prompting a second ventricular lead. Successful transvenous lead placement across a tricuspid annuloplasty ring is possible.     

The value of assessing pulmonary venous flow velocity for predicting severity of mitral regurgitation: A quantitative assessment integrating left ventricular function.

Although alteration in pulmonary venous flow has been reported to relate to mitral regurgitant severity, it is also known to vary with left ventricular (LV) systolic and diastolic dysfunction. There are few data relating pulmonary venous flow to quantitative indexes of mitral regurgitation (MR). The object of this study was to assess quantitatively the accuracy of pulmonary venous flow for predicting MR severity by using transesophageal echocardiographic measurement in patients with variable LV dysfunction. This study consisted of 73 patients undergoing heart surgery with mild to severe MR. Regurgitant orifice area (ROA), regurgitant stroke volume (RSV), and regurgitant fraction (RF) were obtained by quantitative transesophageal echocardiography and proximal isovelocity surface area. Both left and right upper pulmonary venous flow velocities were recorded and their patterns classified by the ratio of systolic to diastolic velocity: normal (>/=1), blunted (<1), and systolic reversal (<0). Twenty-three percent of patients had discordant patterns between the left and right veins. When the most abnormal patterns either in the left or right vein were used for analysis, the ratio of peak systolic to diastolic flow velocity was negatively correlated with ROA (r = -0.74, P <.001), RSV (r = -0.70, P <.001), and RF (r = -0.66, P <.001) calculated by the Doppler thermodilution method; values were r = -0.70, r = -0.67, and r = -0.57, respectively (all P <.001), for indexes calculated by the proximal isovelocity surface area method. The sensitivity, specificity, and predictive values of the reversed pulmonary venous flow pattern for detecting a large ROA (>0.3 cm(2)) were 69%, 98%, and 97%, respectively. The sensitivity, specificity, and predictive values of the normal pulmonary venous flow pattern for detecting a small ROA (<0.3 cm(2)) were 60%, 96%, and 94%, respectively. However, the blunted pattern had low sensitivity (22%), specificity (61%), and predictive values (30%) for detecting ROA of greater than 0.3 cm(2) with significant overlap with the reversed and normal patterns. Among patients with the blunted pattern, the correlation between the systolic to diastolic velocity ratio was worse in those with LV dysfunction (ejection fraction <50%, r = 0.23, P >.05) than in those with normal LV function (r = -0.57, P <.05). Stepwise linear regression analysis showed that the peak systolic to diastolic velocity ratio was independently correlated with RF (P <.001) and effective stroke volume (P <.01), with a multiple correlation coefficient of 0.71 (P <.001). In conclusion, reversed pulmonary venous flow in systole is a highly specific and reliable marker of moderately severe or severe MR with an ROA greater than 0.3 cm(2), whereas the normal pattern accurately predicts mild to moderate MR. Blunted pulmonary venous flow can be seen in all grades of MR with low predictive value for severity of MR, especially in the presence of LV dysfunction. The blunted pulmonary venous flow pattern must therefore be interpreted cautiously in clinical practice as a marker for severity of MR.     

CT在肺动脉高压诊断及右心功能评价中的研究进展

目的 CT作为一种非侵入性影像检查技术,在诊断肺动脉高压和评价右心功能方面得到了越来越多的关注.CT评价肺动脉高压大致可分为基于形态学和基于功能学.本文对CT在肺动脉高压的诊断和右心功能评价中的研究进展进行综述.     

流速指标对肾动脉狭窄的诊断价值

目的　探讨流速指标对内径减少≥ 5 0 %的肾动脉狭窄 (RAS)的诊断价值和确定最佳阈值。方法　经彩色多普勒血流显像 (CDFI)检查后并进行肾动脉造影的 187条肾动脉构成研究组。测量肾动脉峰值流速(PSV)、肾动脉与腹主动脉PSV比率 (RAR)、肾动脉与叶间动脉PSV比率 (RIR)和叶间动脉PSV。肾动脉造影显示肾动脉内径减少≥ 5 0 %者定为RAS。使用ROC曲线 (receiveoperatingcharacteristiccurves)分析确定最佳诊断指标。计算这些流速指标不同阈值的敏感性、特异性、阳性预测值和阴性预测值。结果　肾动脉造影共显示180条主肾动脉和 7条副肾动脉 ,其中 13条完全闭塞和 93条内径减少 5 0 %～ 99% (大动脉炎性 3 0条 ,纤维肌性发育不良性 2 1条 ,动脉粥样硬化性 42条 )。肾动脉CDFI探测成功率为 96% (180 / 187)。ROC曲线分析结果显示RIR是最好的流速指标。RIR >5、肾动脉PSV >15 0cm /s、RAR >2、叶间动脉PSV <2 5cm/s的敏感性依次分别为 88%、81%、70 %、74%。RIR >5与叶间动脉PSV <15cm /s提供了最好的结合 ,敏感性为 91% ,特异性为87%。结论　对于RAS的诊断 ,RIR是最好的流速指标 ,叶间动脉PSV是最差的流速指标 ,RAR >3能够比较自信地诊断RAS。注意肾动脉PSV的影响因素并联合各类流速指标有助于减少误诊。     

CT signs of right ventricular dysfunction correlated with echocardiography-derived pulmonary arterial systolic pressure: incremental value of the pulmonary arterial diameter index

To investigate and compare the potential of right to left ventricular volume (RVV/LVV) and diameter ratios (RVD/LVD) for the prediction of pulmonary arterial hypertension (PH) over 40 mmHg, and then to evaluate the incremental value of the pulmonary artery diameter index (PADi; PAD/body surface area) in the prediction of PH over 40 mHg. We correlated the followings on chest CT with same-day echocardiography-derived pulmonary arterial systolic pressure (PASP) in 139 patients (64.8 ± 15.4 years; 63 male): PADi, RVD/LVD on axial (RVD_axial/LVD_axial) and four chamber (RVD_4CH/LVD_4CH) views, and RVV/LVV. Those were then adjusted (multiplied) by PADi. Areas under the curves (AUC) for predicting PASP > 40 mmHg were calculated. All patients had undergone non-ECG-gated, contrast enhanced chest CT on a 64-slice multi-detector CT system. The correlation of PASP with RVV/LVV (R² = 0.45) was stronger than with RVD_axial/LVD_axial (R² = 0.28) and RVD_4CH/LVD_4CH (R² = 0.34). When adjusted by PADi, the correlation improved; R² = 0.55, 0.41 and 0.47, respectively. The AUC of adjusted RVV/LVV was significantly higher than those of other CT measurements (P < 0.05) excluding adjusted RVD_4CH/LVD_4CH (P = 0.08). With 18.80 as the cutoff, its sensitivity and specificity for predicting PH > 40 mmHg were 83 and 87 %, respectively. Ventricular volume is superior to ventricular diameter ratios in the prediction of PH > 40 mmHg with better correlation with PASP. PADi adds incremental value to these measurements in the prediction of PH > 40 mmHg. Of those, adjusted RVV/LVV is most reliable and predicts PH > 40 mmHg with fairly high sensitivity and specificity.     

定量组织速度成像法和血流多普勒测量Tei指数评价肺动脉高压右室功能的对比性研究

目的运用定量组织速度成像技术(QTVI)测定肺动脉高压患者的右心Tei指数,与传统血流多普勒方法作对比性研究,探讨QTVI法测量Tei指数在临床评价右心功能的应用价值。方法入选病例:肺动脉高压患者91例,分为轻、中、重三组;正常对照组52例。分别利用脉冲血流多普勒成像(PW)和QTVI技术,测算研究对象的Tei指数。结果①QTVI和PW法所测肺动脉高压患者Tei指数均较正常对照组高,且差异有统计学意义。(PW法测得正常人与不同程度肺动脉高压患者Tei指数分别为0.28±0.07,0.29±0.12,0.48±0.14,0.70±0.30;QTVI法分别为0.32±0.10,0.41±0.15,0.56±0.13,0.84±0.21,P<0.05)。②QTVI与PW法所测研究对象的右室Tei指数相比,QTVI所测值均高于相对应的PW方法,(正常组0.32±0.10与0.28±0.07,肺高压组分别为0.41±0.15与0.29±0.12,0.48±0.14与0.56±0.13,0.70±0.30与0.84±0.2,P<0.05)差异均有统计学意义。③QTVI法测得Tei指数与肺动脉压力相关系数较PW高,评价右心功能的特异度及敏感度均较PW高(相关系数分别为r=0.71与r=0.61,评价心功能的敏感度分别为86.7%、75.9%;特异度为80.0%、65.5%)。结论利用QTVI测算Tei指数可准确评价心脏整体和局部功能,为评价肺动脉高压患者的右心功能提供了一种可靠的、无创性的、新的检测手段。     

Strain and strain rate echocardiography for evaluation of right ventricular dysfunction in patients with idiopathic pulmonary arterial hypertension

Optimizing the non-invasive imaging of right ventricular (RV) function is of increasing interest for therapy monitoring and risk stratification in patients with idiopathic pulmonary hypertension (IPAH). Therefore, this study evaluated strain and strain rate echocardiography as a tool for comprehensive assessment of RV function and disease severity in IPAH patients. In 30 IPAH patients [WHO functional classes II–IV; mean pulmonary artery pressure (mPAP) 48.8 ± 12.5 mmHg; pulmonary vascular resistance (PVR) 7.9 ± 5.3 Wood units] and in 10 matched healthy control subjects’ two-dimensional echocardiography, 6-MWD and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were obtained. In IPAH patients when compared with controls, RV systolic strain (−18.8 ± 4.3 vs. −34.5 ± 3.8%, p = 0.0016) and strain rate (−1.6 ± 0.6 vs. −2.7 ± 0.5 s⁻¹, p = 0.018) were significantly altered and correlated significantly with elevated NT-proBNP levels (r = 0.73 and r = 0.62; p < 0.001, respectively) and reduced 6-MWD (r = −0.76 and r = −0.81; p < 0.001). In IPAH patients, reduced strain correlated with both mPAP (r = 0.61, p = 0.01 for strain; and r = 0.55, p = 0.04 for strain rate, respectively), and PVR (r = 0.84, p < 0.001 for strain; and r = 0.67, p < 0.001 for strain rate, respectively). This study gives first comprehensive evidence that strain echocardiography allows accurate non-invasive assessment of RV function and disease severity in patients with IPAH.