Hemodynamics In Pulmonary Hypertension Research Articles

Dissecting contributions of pulmonary arterial remodeling to right ventricular afterload in pulmonary hypertension.

Pulmonary hypertension (PH) is defined as an elevation in the right ventricle (RV) afterload, characterized by increased hemodynamic pressure in the main pulmonary artery (PA). Elevations in RV afterload increase RV wall stress, resulting in RV remodeling and potentially RV failure. From a biomechanical standpoint, the primary drivers for RV afterload elevations include increases in pulmonary vascular resistance (PVR) in the distal vasculature and decreases in vessel compliance in the proximal PA. However, the individual contributions of the various vascular remodeling events toward the progression of PA pressure elevations and altered vascular hemodynamics remain elusive. In this study, we used a subject-specific one-dimensional (1D) fluid-structure interaction (FSI) model to investigate the alteration of pulmonary hemodynamics in PH and to quantify the contributions of vascular stiffening and increased resistance towards increased main pulmonary artery (MPA) pressure. We used a combination of subject-specific hemodynamic measurements, ex-vivo mechanical testing of arterial tissue specimens, and ex-vivo X-ray micro-tomography imaging to develop the 1D-FSI model and dissect the contribution of PA remodeling events towards alterations in the MPA pressure waveform. Both the amplitude and pulsatility of the MPA pressure waveform were analyzed. Our results indicated that increased distal resistance has the greatest effect on the increase in maximum MPA pressure, while increased stiffness caused significant elevations in the characteristic impedance. The method presented in this study will serve as an essential step toward understanding the complex interplay between PA remodeling events that leads to the most severe adverse effect on RV dysfunction.

Multidimensional CT approach to predict hemodynamics in pulmonary hypertension

Computed tomographic pulmonary angiography (CTPA) allows an excellent visualization of heart chambers and vessels, which may be associated with hemodynamic status in pulmonary hypertension, obviating the need for repetitive right heart catheterization (RHC). In this study, we aimed to evaluate the capacity of CTPA to predict severe hemodynamics and to correlate with clinical status and events. Retrospective study with 51 patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) in whom a CTPA and RHC were performed within 6 months. The primary endpoint was to evaluate the CTPA performance to predict severe hemodynamics, defined as the best mPAP threshold with clinical impact. Secondary endpoints were the correlation of CTPA measurements with clinical outcomes. The right ventricle (RV) and right atrium (RA) areas, RV-free wall thickness, septal angle and pulmonary artery diameter assessed by CTPA revealed a good capacity to predict severe hemodynamic status. A CTPA model, incorporating both an RV area above 23 cm2 and an RA area above 21 cm2, increased the prediction capacity to detect severe hemodynamic status. The presence of both parameters above the threshold predicted severe PH with a 100% specificity and a 52% sensitivity and conveyed a 5-fold increased risk of mortality during follow-up. CTPA-altered parameters were directly associated with higher NT-proBNP levels and worse WHO-FC at baseline and follow-up. In this pilot study, a CTPA model was able to predict severe PH hemodynamic status and worse clinical events during follow-up.

Легенева гіпертензія при сепсисі в дітей та її корекція за допомогою донатора оксиду азоту L-аргініну

У статті обговорюється проблема гемодинамічних розладів у малому колі кровообігу при сепсисі, тяжкому сепсисі та септичному шоку в дітей. Продемонстровано наявність легеневої гіпертензії, що виявляється при дослідженні середнього артеріального тиску в легеневій артерії методом допплерометрії за Kitabatake. Також показано, що легенева гіпертензія поєднується з розладами системної гемодинаміки та тканинною гіпоксією, які існують, незважаючи на збільшення рівня NO у крові. Наведено результати впливу внутрішньовенної інфузії аргініну гідрохлориду на показники вмісту оксиду азоту в сироватці та показники центральної та легеневої гемодинаміки при легеневій гіпертензії на тлі септичних станів у дітей. Продемонстровано здатність внутрішньовенної інфузії аргініну гідрохлориду в дозі 5 мл/кг/добу протягом 24–48 годин вірогідно збільшувати вміст NO у крові та знижувати тиск у легеневій артерії й легеневий судинний опір при септичних станах у дітей.

Measurement of Pulmonary Artery Wave Reflection Before and After Mitral Valvuloplasty in Canine Patients With Pulmonary Hypertension Caused by Myxomatous Mitral Valve Disease.

Background: Pulmonary arterial wave reflection provides novel information about pulmonary artery hemodynamics in pulmonary hypertension (PH). PH is common in dogs with myxomatous mitral valve disease (MMVD), though research examining the relationship between pulmonary arterial wave reflection and MMVD with PH is lacking.Hypothesis/Objective: This study investigated conventional echocardiographic parameters and pulmonary artery wave reflection parameters before and after mitral valvuloplasty in canine patients with PH due to MMVD. The parameters were backward pressure (Pb), forward pressure (Pf), and the reflection coefficient calculated as the ratio of peak Pb to peak Pf (RC).Animals: The study subjects were 10 client-owned dogs receiving mitral valvuloplasty for MMVD with PH.Methods: Conventional echocardiographic parameters and pulmonary artery wave reflection parameters were measured before and after mitral valvuloplasty. The relationships between pulmonary artery wave reflection parameters and echocardiographic parameters, estimation of pulmonary artery systolic pressure, and right atrium pressure (RAP) gained by catheter in mitral valvuloplasty were also investigated. Post-operative echocardiography and the measurement of pulmonary arterial wave reflection were performed 2 weeks after mitral valvuloplasty.Results: The parameters of normalized left ventricular internal diameter at end-diastole (LVIDDN), E velocity, and the estimation of pulmonary artery systolic pressure were significantly reduced post-operatively compared with baseline measurements (p < 0.05). Post-operative Pb decreased significantly compared with pre-operative measurements (8.8 ± 5.9 to 5.0 ± 3.2 mmHg, p = 0.037) as did RC (0.37 ± 0.15 to 0.22 ± 0.11, p < 0.01). A statistically significant positive correlation existed between wave reflection parameters and RAP, an estimation of pulmonary artery systolic pressure.Conclusions: Results demonstrate that mitral valvuloplasty can be used to treat secondary PH caused by MMVD, resulting in the improvement of post-operative echocardiographic and wave reflection parameters and a decrease in the right afterload. In some patients, some degree of vascular admittance mismatch persisted, despite the improvement of left atrial pressure. This may be indicative of residual pulmonary arterial disease, which may continue to adversely affect interactions between the right ventricle and the vasculature.

Non-invasive Assessment of Pulmonary Artery Wave Reflection in Dogs With Suspected Pulmonary Hypertension.

Background: Pulmonary arterial wave reflection (PAWR) occurs when the forward blood flow out the right ventricle is reflected by the pulmonary arterial tree, generating a backward wave. PAWR assessed by cardiac catheterization has been used to obtain information regarding pulmonary artery hemodynamics in pulmonary hypertension (PH) in people. However, diagnostic cardiac catheterization is not commonly used in small animal medicine because it is invasive and requires anesthesia.Hypothesis/Objective: To investigate whether PAWR can be assessed non-invasively in dogs with suspected PH using Doppler echocardiography, based on wave intensity analysis (WIA). In addition, the method was validated in a dog model of acute pulmonary embolism.Animals: Fifty-one client-owned dogs with tricuspid valve regurgitation were included in the clinical study (35 with suspected PH and 16 without echocardiographic evidence of PH) and eight healthy beagle dogs were included in the validation study.Methods: PAWR was assessed by separating pulmonary artery pulse pressure waveforms, which were estimated from the flow profile of tricuspid regurgitation, into forward (Pf) and backward pressures (Pb) using WIA. Reflection coefficient (RC) was defined as the ratio of peak Pb to peak Pf. We investigated the relationships between RC, cause, and survival time in dogs with suspected PH. In addition, we performed a validation study to compare PAWR obtained by cardiac catheterization and PAWR by Doppler echocardiography in dogs with experimentally-induced PH.Results: RC was significantly higher in dogs with suspected PH than in dogs without echocardiographic evidence of PH (0.18 ± 0.13 vs. 0.59 ± 0.21, P < 0.001). A characteristic reflected waveform appeared depending on the cause of PH. Kaplan-Meier survival curves showed that dogs with RC > 0.48 had a significantly shorter survival time than dogs with RC <0.48 (x2 = 9.8, log-rank test, p = 0.0018, median survival time 353 days vs. 110 days). In the validation study, RC obtained by Doppler echocardiography was significantly correlated with RC obtained by cardiac catheterization (r = 0.81, P < 0.001).Conclusions: PAWR analysis performed by echocardiography seems feasible in dogs and could provide useful information for classification and prognosis in canine PH.

Regional Right Ventricular Abnormalities Implicate Distinct Pathophysiological Conditions in Patients With Chronic Thromboembolic Pulmonary Hypertension.

BackgroundRight ventricular (RV) dysfunction is a prognostic factor for cardiovascular disease. However, its mechanism and pathophysiology remain unknown. We investigated RV function using RV‐specific 3‐dimensional (3D)‐speckle‐tracking echocardiography (STE) in patients with chronic thromboembolic pulmonary hypertension. We also assessed regional wall motion abnormalities in the RV and chronological changes during balloon pulmonary angioplasty (BPA).Methods and ResultsTwenty‐nine patients with chronic thromboembolic pulmonary hypertension who underwent BPA were enrolled and underwent right heart catheterization and echocardiography before, immediately after, and 6 months after BPA. Echocardiographic assessment of RV function included both 2‐dimensional‐STE and RV‐specific 3D‐STE. Before BPA, global area change ratio measured by 3D‐STE was significantly associated with invasively measured mean pulmonary artery pressure and pulmonary vascular resistance (r=0.671 and r=0.700, respectively). Dividing the RV into the inlet, apex, and outlet, inlet area change ratio showed strong correlation with mean pulmonary artery pressure and pulmonary vascular resistance before BPA (r=0.573 and r=0.666, respectively). Only outlet area change ratio was significantly correlated with troponin T values at 6 months after BPA (r=0.470), and its improvement after BPA was delayed compared with the inlet and apex regions. Patients with poor outlet area change ratio were associated with a delay in RV reverse remodeling after treatment.ConclusionsRV‐specific 3D‐STE analysis revealed that 3D RV parameters were novel useful indicators for assessing RV function and hemodynamics in pulmonary hypertension and that each regional RV portion presents a unique response to hemodynamic changes during treatment, implicating that evaluation of RV regional functions might lead to a new guide for treatment strategies.

Relationship between Peripheral Arterial Stiffness and Estimated Pulmonary Pressure by Echocardiography in Systemic Sclerosis.

Pulmonary hypertension (PH) is an important lethal manifestation of systemic sclerosis (SSc). Evidence of an association between peripheral and pulmonary arterial vasculopathy in SSc has been demonstrated. We hypothesized that peripheral arterial stiffness could predict PH in SSc. We performed a cross-sectional study among patients with SSc who underwent Cardio-Ankle Vascular Index (CAVI, VaSera VS-1000; Fukuda Denshi, Tokyo, Japan) and transthoracic echocardiography (TTE) examination to evaluate peripheral arterial stiffness and PH, respectively. The correlation between CAVI score and PH hemodynamics [right ventricular systolic pressure (RVSP) and tricuspid regurgitation velocity (TRV)] was studied. A total of 145 patients underwent both CAVI and TTE evaluation. The mean (standard deviation, SD) patient age was 51.5 (12.3) years; female patients constituted 72% of the subjects. Diffuse SSc occurred in 75% of the cases. The mean (SD) CAVI score was 7.6 (0.9), and the mean (SD) RVSP was 29.9 (11.2) mmHg. Correlation coefficient (r) between CAVI score and RVSP in overall, limited, and diffuse SSc were 0.107 (p = 0.200), 0.040 (p = 0.815), and 0.194 (p = 0.043), respectively. CAVI scores were borderline or abnormal (≥ 8) in 30.3% of subjects. PH was classified intermediate or high probability (TRVmax ≥ 2.9 m/s) in 19.3% of the subjects. Among the overall population, the odds ratios (95% CI) of CAVI score ≥ 8 for TRVmax ≥ 2.9 m/s in univariate and multivariate analysis were 1.23 (0.46-3.21, p = 0.678), and 0.54 (0.10-2.84, p = 0.471), respectively. Peripheral arterial stiffness, as measured by CAVI, has a correlation trend with the level of pulmonary arterial pressure assessed by TTE, specifically in the diffuse SSc subgroup.

Radioechocardiography in the evaluation of pulmonary hypertension

Aim. To study the capabilities of radioechocardigraphy in the evaluation of pulmonary hypertension of various causes, early non-invasive detection of pressure increase in the pulmonary artery.Methods. The study included 800 patients with congenital (269) and acquired (217) mitral valve diseases, pulmonary embolism (140), primary pulmonary hypertension (57), coronary heart disease with acute myocardial infarction (117) of different age and gender. Digital radiography, linear tomography of chest, ECG, echocardiography, multidetector computed tomography angiography, and ultrasound of inferior vena cava were performed.Results. Radiocardiography combined with linear tomography and measurement of Moore index, right atrium index, transpulmonary distance, and width of right descending pulmonary artery at the level of intermediate bronchus, allows determining the degree, type (arterial, venous, capillary, and mixed) and cause of pulmonary hypertension. Digital radiography and linear tomography in 80% cases reveal signs of pulmonary embolism. Echocardiography makes it possible to study hemodynamics in pulmonary hypertension, to detect the dilation of the right heart, inferior vena cava, and renal veins, and to calculate the systolic pressure in the right ventricle, pulmonary artery, and right atrium. Radioechocardigraphy allows determining the cause and degree of pulmonary hypertension, and hemodynamic disorders. Sensitivity of the method for diagnosis of pulmonary hypertension is 89%, specificity is 90%, and precision is 92%.Conclusion. Radioechocardigraphy is a highly effective method for diagnosis of pulmonary hypertension; ultrasound of inferior vena cava, iliac veins, and veins of the lower limbs allows to determine the source of pulmonary embolism, to diagnose embologenicity of thromboses and to evaluate the need for vena cava filters.

Clinical study of right ventricular longitudinal strain for assessing right ventricular dysfunction and hemodynamics in pulmonary hypertension.

This study aimed to appraise the application of right ventricular longitudinal strain for assessing right ventricular dysfunction and severe hemodynamic changes in pulmonary hypertension. The study included 53 patients clinically diagnosed with PH. Tissue Doppler–derived tricuspid lateral annular systolic velocity (s’), early diastolic peak velocity (e’), late diastolic peak velocity (a’), tricuspid annular plane systolic excursion (TAPSE), RV index of myocardial performance (RIMP), and right ventricular fractional area change (FAC) were determined. The STI parameter was RV free wall longitudinal peak systolic strain (RV LPSS). The patients were assigned into two groups based on a RV LPSS value of − 19%.RV LPSS, s’, TAPSE, RIMP, FAC, a’ and e’/a’ showed significant differences. PH patients with an RV LPSS≥ −19% exhibited a lower RV function (P < 0.05). RV LPSS was negatively correlated with TAPSE (r = −0.326, P < 0.05) and FAC (r = −0.495, P < 0.001) and positively correlated with RIMP (r = 0.508, P < 0.001). The optimal cut-off value of RV LPSS to reveal an mPAP ≥ 45 mmHg defined based on the receiver operating characteristic curve analysis was − 19.26% with a sensitivity of 83.9% and a specificity of 73.4%.Distinguishing the degree of RV dysfunction by 2D-STI may help physicians to determine the state of cardiac function and degree of PH in patients and offer a basis for subsequent clinical diagnosis and therapy. Our study demonstrates the superiority of RV LPSS for uncovering severe PH over the traditional echocardiographic parameters.

Evaluation of Pulmonary Hypertension with CMR: Pulmonary Hypertension Patients and Healthy Volunteers Control Study

背景与目的肺高血压（pulmonary hypertension, PH）临床病程表现为进行性恶化和间断急性失代偿发作，死亡可突然或缓慢发生，而临床医生往往对病情的进展评估不足。本研究旨在应用心脏核磁共振（cardiac magnetic resonance, CMR）评估PH患者右心室（right ventricle, RV）形态、功能及主肺动脉（main pulmonary artery, MPA）血液动力学，并与健康人对照，探讨CMR在检出PH中的临床应用价值。方法对56例PH患者及22例健康志愿者进行CMR扫描并获得RV舒张末期容积（end-diastolic volume, EDV）、收缩末期容积（end-systolic volume, ESV）、射血分数（ejection fraction, EF）、心肌质量（myocardial mass, MM）、RV面积变化分数（RV fractional area change, RVFAC）、室间隔与左室游离壁曲率比，MPA正向峰值流速、最大截面积、最小截面积及顺应性。PH组与对照组测量结果采用两独立样本t检验进行比较。受试者工作特征曲线（receiver operating characteristic curve，ROC曲线）用于比较MPA正向峰值流速、顺应性、曲率比、RVFAC单项指标及综合评估检出PH的效能。P < 0.05为差异有统计学意义。结果与对照组相比，PH组RV形态改变、功能明显下降，血液动力学指标恶化。顺应性对检出PH的效能较高（AUC为0.950）；综合应用正向峰值流速、顺应性、曲率比和RVFAC时，检出PH的效能最高（AUC为0.988）。结论CMR综合评估指标有利于准确反映PH患者RV-肺循环整体状态。

Hemodynamics of pulmonary hypertension: Application of the reservoir-wave approach

Hemodynamics of pulmonary hypertension: Application of the reservoir-wave approach

Relation between left ventricular ejection time and pulmonary hemodynamics in pulmonary hypertension

In patients with precapillary pulmonary hypertension (PH), stroke volume is preserved in the early stages of disease as the right ventricle (RV) adapts adequately to the increased afterload. At more evolved stages, adaptive mechanisms become inefficient and stroke volume decreases, progressing to right heart failure and death [1]. We have recently demonstrated that shortened left ventricular ejection time (LVET) is predictive of worse prognosis in precapillary PH with right heart failure [2]. However, the literature remains inconclusive regarding the exact impact of PH on LVET [3–6].

Computed tomography correlates with cardiopulmonary hemodynamics in pulmonary hypertension in adults with sickle cell disease.

Our objective was to determine whether computed tomography angiography (CTA) measurements of pulmonary artery size can noninvasively assess hemodynamics and diagnose pulmonary hypertension (PH) secondary to sickle cell disease (SCD). Twenty SCD patients with confirmed PH were compared with 20 matched controls. Diameters of the pulmonary artery trunk and branches were measured with CTA and a semiautomatic segmentation algorithm. Measurements were normalized by body size and correlated (Spearman rank) with hemodynamic markers from right-heart catheterization. Receiver operating characteristic (ROC) curves were used to investigate the role of pulmonary artery sizes in diagnosing PH. Analysis of pulmonary artery sizes adjusted for body surface area (BSA) resulted in the most significant discrimination between subjects with PH secondary to SCD and controls (P < 0.001); PH was diagnosed accurately with an area under the ROC curve of 0.99. There was significant correlation between pulmonary artery sizes and body mass index (BMI) and BSA only in controls (r = 0.46-0.68, P < 0.04 for all). The most significant correlations with hemodynamic markers were found between BMI-adjusted pulmonary artery sizes and high systolic pulmonary arterial pressure, high pulmonary vascular resistance, high systemic vascular resistance, and low cardiac output (r = 0.47, 0.62, 0.61, and 0.66, respectively; P < 0.04 for all). BMI-adjusted CTA measures of the pulmonary artery relate to high pulmonary vascular resistance and reduced cardiac output in patients with SCD and PH. CTA with quantitative image analysis is a powerful noninvasive diagnostic tool for PH in SCD and shows promise as estimator of hemodynamic markers.

(861) - Hemodynamics of Pulmonary Hypertension in the Setting of Hereditary Hemorrhagic Telangiectasia

To determine the hemodynamic profile of patients with hereditary hemorrhagic telangiectasia (HHT) referred for right heart catheterization and estimate the incidence of pulmonary hypertension (PH) and/or high output states in this setting.

A Simple Echocardiographic Prediction Rule for Hemodynamics in Pulmonary Hypertension

Pulmonary hypertension (PH) has diverse causes with heterogeneous physiology compelling distinct management. Differentiating patients with primarily elevated pulmonary vascular resistance (PVR) from those with PH predominantly because of elevated left-sided filling pressure is critical. We reviewed hemodynamics, echocardiography, and clinical data for 108 patients seen at a referral PH clinic with transthoracic echocardiogram and right heart catheterization within 1 year. We derived a simple echocardiographic prediction rule to allow hemodynamic differentiation of PH attributed to pulmonary vascular disease (PH(PVD), defined as pulmonary artery wedge pressure [PAWP]≤15 mm Hg and PVR>3 WU). Age averaged 61.3±14.8 years, μPAWP and PVR were 16.4±7.1 mm Hg and 6.3±4.0 WU, respectively, and 52 (48.1%) patients fulfilled PH(PVD) hemodynamic criteria. The derived prediction rule ranged from -2 to +2 with higher scores suggesting higher probability of PH(PVD): +1 point for left atrial anterior-posterior dimension <3.2 cm; +1 for presence of a mid systolic notch or acceleration time <80 ms; -1 for lateral mitral E:e'>10; -1 for left atrial anterior-posterior dimension >4.2 cm. PVR increased stepwise with score (for -2, 0, and +2, μPVR were 2.5, 4.5, and 8.1 WU, respectively), whereas the inverse was true for pulmonary artery wedge pressure (corresponding μPAWP were 21.5, 16.5, and 10.4 mm Hg). Among subjects with complete data, the score had an area under the curve (AUC) of 0.921 for PH(PVD). A score ≥0 had 100% sensitivity and 69.3% positive predictive value for PH(PVD), with 62.3% specificity. No patients with a negative score had PH(PVD). Patients with a negative score and acceleration time >100 ms had normal PVR (μPVR=1.8 WU, range=0.7-3.2 WU). We present a simple echocardiographic prediction rule that accurately defines PH hemodynamics, facilitates improved screening and focused clinical investigation for PH diagnosis and management.

The Nuts and Bolts of Interpreting Hemodynamics in Pulmonary Hypertension Associated With Diastolic Heart Failure

With the widespread application of transthoracic echocardiography as a screening tool for pulmonary hypertension (PH), we have come to appreciate the prevalence of PH associated with diastolic heart failure. Diastolic heart failure (DHF, sometimes called heart failure with preserved, or normal, left ventricular ejection fraction [HFpEF]) is quite common, and PH appears to be a fairly frequent component of DHF.1–3 The epidemiology of these conditions is described in the article by Dr Soto in this issue of Advances. There is a complex relationship between DHF and PH: the 2 may exist independent of each other or in combination; and when they exist in combination, the PH may be in proportion or out of proportion to the DHF. Cardiac catheterization is critical in differentiating among these patterns, and this distinction may lead to important modifications in treatment strategy. This requires, however, a full understanding of the proper performance and interpretation of cardiac catheterization, as well as the potential pitfalls that can limit the utility of the procedure. This article will discuss these aspects of cardiac catheterization as they pertain to patients with pulmonary arterial hypertension (PAH) and PH associated with DHF. A number of important aspects of cardiac catheterization are not covered here due to space limitations but can be obtained in a more detailed text.4

Treatment of Sarcoidosis-Associated Pulmonary Hypertension: A Two-Center Experience

Pulmonary hypertension (PH) is a common complication of sarcoidosis that is associated with increased mortality. The pathogenesis of PH in sarcoidosis is uncertain, and the role of pulmonary arterial hypertension (PAH)-specific therapies remains to be determined.We conducted a retrospective study of patients with sarcoidosis and PH at two referral centers. New York Heart Association (NYHA) functional class, exercise capacity, hemodynamic data, pulmonary function tests, and survival were collected and analyzed.Twenty-two sarcoidosis patients treated with PAH-specific therapies were identified. After a median of 11 months of follow-up, NYHA class was improved in nine subjects. Mean 6-min walk distance (n = 18) increased by 59 m (p = 0.032). Patients with a higher FVC experienced a greater increment in exercise capacity. Among 12 patients with follow-up hemodynamic data, mean pulmonary artery pressure was reduced from 48.5 +/- 4.3 to 39.4 +/- 2.8 mm Hg (p = 0.008). The 1- and 3-year transplant-free survival rates were 90% and 74%, respectively.PAH-specific therapy may improve functional class, exercise capacity, and hemodynamics in PH associated with sarcoidosis. Prospective, controlled trials of PAH therapies for sarcoidosis are warranted to verify this apparent benefit. Mortality among the study population was high, highlighting the need for urgent evaluation at a lung transplant center.

Cardiopulmonary Hemodynamics in Pulmonary Hypertension: Pressure Tracings, Waveforms, and More

Cardiopulmonary Hemodynamics in Pulmonary Hypertension: Pressure Tracings, Waveforms, and More

Correlation of Tricuspid Annular Velocities With Invasive Hemodynamics in Pulmonary Hypertension

The authors performed tissue Doppler imaging of the tricuspid annulus in patients with pulmonary hypertension to assess its correlation with invasive indices of right ventricular function. The study population consisted of 32 patients with suspected pulmonary hypertension who underwent pulsed tissue Doppler imaging of the tricuspid annulus and right heart catheterization. Peak systolic (Sa), early diastolic (Ea), and late diastolic (Aa) velocities of the lateral tricuspid annulus were measured and correlated with hemodynamic variables. Peak Sa demonstrated excellent correlation with hemodynamic variables, including cardiac index (r=0.78; P<.001), pulmonary vascular resistance (r=-0.79; P<.001), and transpulmonary gradient (r=-0.72; P<.001). Peak Sa <10 cm/s predicted cardiac index <2.0 L/min/m2 with 89% sensitivity and 87% specificity. In conclusion, tissue Doppler imaging of the tricuspid annulus is a complementary method to assess right ventricular function in pulmonary hypertensive patients.

Evaluation of Pulmonary Artery Banding in the Setting of Ventricular Septal Defects and Severely Elevated Pulmonary Vascular Resistance

Children with pulmonary hypertension secondary to large left-to-right, post-tricuspid valve shunts can eventually have severe and/or irreversible pulmonary vascular disease, yielding them inoperable for conventional surgery. It has been shown, however, that unloading of the pulmonary hypertension can result in remodeling of the pulmonary vasculature and, thus, improvement of the pulmonary hypertension. This study explored whether such patients might experience a significant reduction in pulmonary vascular resistance (PVR) after pulmonary artery band (PAB) placement. Pulmonary hypertension hemodynamics were evaluated by cardiac catheterization in 4 patients with pulmonary hypertension secondary to nonrestrictive left-to-right, post-tricuspid valve shunts before and after PAB placement. Two patients with severe pulmonary hypertension who were considered high risk for conventional surgery benefited from PAB placement with a significant reduction in their PVR, permitting subsequent complete intracardiac repair. The medium-term follow-up for these 2 patients demonstrated good outcomes. The PVR failed to improve after PAB placement in the remaining 2 patients, leading to medical therapy for pulmonary hypertension. There was 1 late death, presumably related to pulmonary hypertension. Current practice provides 3 relatively unattractive options for patients with severe pulmonary hypertension secondary to nonrestrictive left-to-right, post-tricuspid valve shunts: transplantation, high-risk intracardiac repair, or palliative medical therapy. Our study suggests that a staged approach with initial PAB placement can be considered for select patients with large left-to-right, post-tricuspid valve shunts and high PVR prior to committing them to other high-risk therapeutic options.