A modelling study of atrial septostomy for pulmonary arterial hypertension, and its effect on the state of tissue oxygenation and systemic blood flow

2010 ◽  
Vol 20 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Gerhard-Paul Diller ◽  
Astrid E. Lammers ◽  
Sheila G. Haworth ◽  
Konstantinos Dimopoulos ◽  
Graham Derrick ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Right Ventricular ◽  
Tissue Oxygenation ◽  
Arterial Blood ◽  
Atrial Septostomy ◽  
Pulmonary Arterial ◽  
Mixed Venous ◽  
Content Of Oxygen

AbstractAtrial septostomy is performed in patients with severe pulmonary arterial hypertension, and has been shown to improve symptoms, quality of life and survival. Despite recognized clinical benefits, the underlying pathophysiologic mechanisms are poorly understood. We aimed to assess the effects of right-to-left shunting on arterial delivery of oxygen, mixed venous content of oxygen, and systemic cardiac output in patients with pulmonary arterial hypertension and a fixed flow of blood to the lungs. We formulated equations defining the mandatory relationship between physiologic variables and delivery of oxygen in patients with right-to-left shunting. Using calculus and computer modelling, we considered the simultaneous effects of right-to-left shunting on physiologies with different pulmonary flows, total metabolic rates, and capacities for carrying oxygen. Our study indicates that, when the flow of blood to the lungs is fixed, increasing right-to-left shunting improves systemic cardiac output, arterial blood pressure, and arterial delivery of oxygen. In contrast, the mixed venous content of oxygen, which mirrors the average state of tissue oxygenation, remains unchanged. Our model suggests that increasing the volume of right-to-left shunting cannot compensate for right ventricular failure. Atrial septostomy in the setting of pulmonary arterial hypertension, therefore, increases the arterial delivery of oxygen, but the mixed systemic saturation of oxygen, arguably the most important index of tissue oxygenation, stays constant. Our data suggest that the clinically observed beneficial effects of atrial septostomy are the result of improved flow of blood rather than augmented tissue oxygenation, provided that right ventricular function is adequate.

scholarly journals Transition from selexipag to oral treprostinil in a patient with pulmonary arterial hypertension

2020 ◽  
Vol 10 (1) ◽  
pp. 204589401989803 ◽  
Author(s):  
Ifeoma Oriaku ◽  
Amol Patel ◽  
Zeenat Safdar
Keyword(s):  
Cardiac Output ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Maximum Dose ◽  
Mixed Venous Oxygen Saturation ◽  
Maximal Dose ◽  
Venous Oxygen Saturation ◽  
Pulmonary Arterial ◽  
Mixed Venous ◽  
Severe Pulmonary Arterial Hypertension

Prostacyclins are the mainstay treatment for patients with severe pulmonary arterial hypertension. This case highlights the transition from selexipag to oral treprostinil. Our patient improved both subjectively and objectively. Cardiac output and index, as measured by the echocardiogram, improved 12% and 7.7%, respectively. Invasive hemodynamic data revealed greater improvements: cardiac output improved by 25% and cardiac index by 28%. Mixed venous oxygen saturation improved from 65% to 71%. A possible explanation is that selexipag has a maximal dose, whereas there is no recommended maximum dose of oral treprostinil. Another theory is oral treprostinil has higher affinity to the IP receptor, though selexipag has a higher specificity. However, there are no bio-equivalency data, and data comparing pharmacodynamics of both drugs are lacking. Furthermore, no head-to-head trials comparing these agents exist.

scholarly journals Direct and indirect protection of right ventricular function by estrogen in an experimental model of pulmonary arterial hypertension

2014 ◽  
Vol 307 (3) ◽  
pp. H273-H283 ◽  
Author(s):  
Aiping Liu ◽  
David Schreier ◽  
Lian Tian ◽  
Jens C. Eickhoff ◽  
Zhijie Wang ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Pulmonary Arterial Hypertension ◽  
Ejection Fraction ◽  
Arterial Hypertension ◽  
Right Ventricular ◽  
Therapeutic Potential ◽  
Systolic Function ◽  
Arterial Compliance ◽  
Pulmonary Arterial

Pulmonary arterial hypertension (PAH) results in right ventricular (RV) dysfunction and failure. Paradoxically, women are more frequently diagnosed with PAH but have better RV systolic function and survival rates than men. The mechanisms by which sex differences alter PAH outcomes remain unknown. Here, we sought to study the role of estrogen in RV functional remodeling in response to PAH. The SU5416-hypoxia (SuHx) mouse model of PAH was used. To study the role of estrogen, female mice were ovariectomized and then treated with estrogen or placebo. SuHx significantly increased RV afterload and resulted in RV hypertrophy. Estrogen treatment attenuated the increase in RV afterload compared with the untreated group (effective arterial elastance: 2.3 ± 0.1 mmHg/μl vs. 3.2 ± 0.3 mmHg/μl), and this was linked to preserved pulmonary arterial compliance (compliance: 0.013 ± 0.001 mm2/mmHg vs. 0.010 ± 0.001 mm2/mmHg; P < 0.05) and decreased distal muscularization. Despite lower RV afterload in the estrogen-treated SuHx group, RV contractility increased to a similar level as the placebo-treated SuHx group, suggesting an inotropic effect of estrogen on RV myocardium. Consequently, when compared with the placebo-treated SuHx group, estrogen improved RV ejection fraction and cardiac output (ejection fraction: 57 ± 2% vs. 44 ± 2% and cardiac output: 9.7 ± 0.4 ml/min vs. 7.6 ± 0.6 ml/min; P < 0.05). Our study demonstrates for the first time that estrogen protects RV function in the SuHx model of PAH in mice directly by stimulating RV contractility and indirectly by protecting against pulmonary vascular remodeling. These results underscore the therapeutic potential of estrogen in PAH.

scholarly journals Interventional and Surgical Treatments for Pulmonary Arterial Hypertension

2021 ◽  
Vol 10 (15) ◽  
pp. 3326
Author(s):  
Tomasz Stącel ◽  
Magdalena Latos ◽  
Maciej Urlik ◽  
Mirosław Nęcki ◽  
Remigiusz Antończyk ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Interdisciplinary Approach ◽  
Left Ventricular ◽  
Free Survival ◽  
Atrial Septostomy ◽  
Surgical Options ◽  
Pulmonary Arterial ◽  
Va Ecmo ◽  
Surgical Treatments

Despite significant advancements in pharmacological treatment, interventional and surgical options are still viable treatments for patients with pulmonary arterial hypertension (PAH), particularly idiopathic PAH. Herein, we review the interventional and surgical treatments for PAH. Atrial septostomy and the Potts shunt can be useful bridging tools for lung transplantation (Ltx), which remains the final surgical treatment among patients who are refractory to any other kind of therapy. Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) remains the ultimate bridging therapy for patients with severe PAH. More importantly, VA-ECMO plays a crucial role during Ltx and provides necessary left ventricular conditioning during the initial postoperative period. Pulmonary denervation may potentially be a new way to ensure better transplant-free survival among patients with the aforementioned disease. However, high-quality randomized controlled trials are needed. As established, obtaining the Eisenmenger physiology among patients with severe pulmonary hypertension by creating artificial defects is associated with improved survival. However, right-to-left shunting may be harmful after Ltx. Closure of the artificially created defects may carry some risk associated with cardiac surgery, especially among patients with Potts shunts. In conclusion, PAH requires an interdisciplinary approach using pharmacological, interventional, and surgical modalities.

scholarly journals preoperative right ventricular overwork is a major determinant of residual pulmonary arterial hypertension in patients with repaired arterial septal defect

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
M Suzuki ◽  
Y Tanaka ◽  
K Yamashita ◽  
A Shono ◽  
K Sumimoto ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Right Ventricular ◽  
Septal Defect ◽  
Hazard Ratio ◽  
Coupling Index ◽  
Pulmonary Arterial ◽  
Asd Closure ◽  
The Right ◽  
Postoperative Residual

Abstract Funding Acknowledgements Type of funding sources: None. Background The haemodynamic effect of atrial septal defect (ASD) is a chronic volume overload of the right heart and pulmonary vasculature. Pulmonary overcirculation is generally compensated for by the right ventricular (RV) and pulmonary arterial (PA) reserve. However, in a subset of patients, prolonged pulmonary overcirculation insidiously induces obstructive pulmonary vasculopathy, which results in postoperative residual pulmonary arterial hypertension (PAH) after ASD closure. Postoperative PAH is a major concern because it is closely associated with poor outcomes and impaired quality of life. However, to date, no clinically robust predictors of postoperative residual PAH have been clearly identified. Purpose This study sought to assess the haemodynamic characteristics of ASD patients in terms of mechano-energetic parameters and to identify the predictors of postoperative residual PAH in these patients. Methods A total of 120 ASD patients (age: 58 ± 17 years) and 46 normal controls were recruited. As previously reported, the simplified RV contraction pressure index (sRVCPI) was calculated as an index of RV external work by multiplying the tricuspid annular plane systolic excursion (TAPSE) by the pressure gradient between the RV and right atrium. RV- PA coupling was evaluated using TAPSE divided by PA systolic pressure as an index of the RV length-force relationship. These parameters were measured both at baseline and 6 months after ASD closure. Results As expected, baseline sRVCPI was significantly greater in patients with ASD than in controls (775 ± 298 vs. 335 ± 180 mm Hg • mm, P &lt; 0.01), which indicated significant "RV overwork". As a result, RV-PA coupling in ASD patients was significantly impaired compared to that in controls (0.9 ± 0.8 vs. 3.5 ± 1.7 mm/mm Hg, P &lt; 0.01). All 120 ASD patients underwent transcatheter or surgical shunt closure; 15 of them had residual PAH after closure. After 6 months, RV-PA coupling index significantly improved in patients without residual PAH, from 0.96 ± 0.81 to 1.27 ± 1.24 mm/mm Hg (P = 0.02). Furthermore, RV load was markedly reduced, with sRVCPI falling from 691 ± 258 to 434 ± 217 mm Hg • mm, P &lt; 0.01). However, in patients with residual PAH, RV-PA coupling index deteriorated from 0.64 ± 0.23 to 0.53 ± 0.12 mm/mm Hg (P &lt; 0.01). As a result, RV overload was not significantly relieved (sRVCPI; from 971 ± 382 to 783 ± 166 mm Hg • mm, P = 0.22). In a multivariate analysis, baseline pulmonary vascular resistance (hazard ratio 1.009; P &lt; 0.01) and preoperative sRVPCI (hazard ratio 1.003; P &lt; 0.01) revealed to be independent predictors of residual PAH. Conclusion In terms of mechano-energetic function, preoperative "RV overwork" can be used as a robust predictor of an impaired RV-PA relationship in ASD patients. Moreover, periodic assessment of sRVPCI may contribute to the better management for patients with unrepaired ASD. Abstract Figure.

scholarly journals Comparative analysis on the anti-inflammatory/immune effect of mesenchymal stem cell therapy for the treatment of pulmonary arterial hypertension

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Seyeon Oh ◽  
Albert Y. Jang ◽  
Sehyun Chae ◽  
Seungbum Choi ◽  
Jeongsik Moon ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Right Ventricular ◽  
Ventricular Function ◽  
Right Ventricular Function ◽  
Treated Group ◽  
Therapeutic Effects ◽  
Mesenchymal Stem Cell Therapy ◽  
Adaptive Immune Cells ◽  
Pulmonary Arterial

AbstractDespite the advancement of targeted therapy for pulmonary arterial hypertension (PAH), poor prognosis remains a reality. Mesenchymal stem cells (MSCs) are one of the most clinically feasible alternative treatment options. We compared the treatment effects of adipose tissue (AD)-, bone marrow (BD)-, and umbilical cord blood (UCB)-derived MSCs in the rat monocrotaline-induced pulmonary hypertension (PH) model. The greatest improvement in the right ventricular function was observed in the UCB-MSCs treated group. The UCB-MSCs treated group also exhibited the greatest improvement in terms of the largest decrease in the medial wall thickness, perivascular fibrosis, and vascular cell proliferation, as well as the lowest levels of recruitment of innate and adaptive immune cells and associated inflammatory cytokines. Gene expression profiling of lung tissue confirmed that the UCB-MSCs treated group had the most notably attenuated immune and inflammatory profiles. Network analysis further revealed that the UCB-MSCs group had the greatest therapeutic effect in terms of the normalization of all three classical PAH pathways. The intravenous injection of the UCB-MSCs, compared with those of other MSCs, showed superior therapeutic effects in the PH model for the (1) right ventricular function, (2) vascular remodeling, (3) immune/inflammatory profiles, and (4) classical PAH pathways.

scholarly journals Right ventricular stroke work index by echocardiography in adult patients with pulmonary arterial hypertension

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Raluca Jumatate ◽  
Annika Ingvarsson ◽  
Gustav Jan Smith ◽  
Anders Roijer ◽  
Ellen Ostenfeld ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Right Ventricular ◽  
Adult Patients ◽  
Stroke Work ◽  
Non Invasive ◽  
Work Index ◽  
Stroke Work Index ◽  
Pulmonary Arterial ◽  
Rv Function

Abstract Background In adult patients with pulmonary arterial hypertension (PAH), right ventricular (RV) failure may worsen rapidly, resulting in a poor prognosis. In this population, non-invasive assessment of RV function is challenging. RV stroke work index (RVSWI) measured by right heart catheterization (RHC) represents a promising index for RV function. The aim of the present study was to comprehensively evaluate non-invasive measures to calculate RVSWI derived by echocardiography (RVSWIECHO) using RHC (RVSWIRHC) as a reference in adult PAH patients. Methods Retrospectively, 54 consecutive treatment naïve patients with PAH (65 ± 13 years, 36 women) were analyzed. Echocardiography and RHC were performed within a median of 1 day [IQR 0–1 days]. RVSWIRHC was calculated as: (mean pulmonary arterial pressure (mPAP)—mean right atrial pressure (mRAP)) x stroke volume index (SVI)RHC. Four methods for RVSWIECHO were evaluated: RVSWIECHO-1 = Tricuspid regurgitant maximum pressure gradient (TRmaxPG) x SVIECHO, RVSWIECHO-2 = (TRmaxPG-mRAPECHO) x SVIECHO, RVSWIECHO-3 = TR mean gradient (TRmeanPG) x SVIECHO and RVSWIECHO-4 = (TRmeanPG–mRAPECHO) x SVIECHO. Estimation of mRAPECHO was derived from inferior vena cava diameter. Results RVSWIRHC was 1132 ± 352 mmHg*mL*m−2. In comparison with RVSWIRHC in absolute values, RVSWIECHO-1 and RVSWIECHO-2 was significantly higher (p < 0.001), whereas RVSWIECHO-4 was lower (p < 0.001). No difference was shown for RVSWIECHO-3 (p = 0.304). The strongest correlation, with RVSWIRHC, was demonstrated for RVSWIECHO-2 (r = 0.78, p < 0.001) and RVSWIECHO-1 ( r = 0.75, p < 0.001). RVSWIECHO-3 and RVSWIECHO-4 had moderate correlation (r = 0.66 and r = 0.69, p < 0.001 for all). A good agreement (ICC) was demonstrated for RVSWIECHO-3 (ICC = 0.80, 95% CI 0.64–0.88, p < 0.001), a moderate for RVSWIECHO-4 (ICC = 0.73, 95% CI 0.27–0.87, p < 0.001) and RVSWIECHO-2 (ICC = 0.55, 95% CI − 0.21–0.83, p < 0.001). A poor ICC was demonstrated for RVSWIECHO-1 (ICC = 0.45, 95% CI − 0.18–0.77, p < 0.001). Agreement of absolute values for RVSWIECHO-1 was − 772 ± 385 (− 50 ± 20%) mmHg*mL*m−2, RVSWIECHO-2 − 600 ± 339 (-41 ± 20%) mmHg*mL*m−2, RVSWIECHO-3 42 ± 286 (5 ± 25%) mmHg*mL*m−2 and for RVSWIECHO-4 214 ± 273 (23 ± 27%) mmHg*mL*m−2. Conclusion The correlation with RVSWIRHC was moderate to strong for all echocardiographic measures, whereas only RVSWIECHO-3 displayed high concordance of absolute values. The results, however, suggest that RVSWIECHO-1 or RVSWIECHO-3 could be the preferable echocardiographic methods. Prospective studies are warranted to evaluate the clinical utility of such measures in relation to treatment response, risk stratification and prognosis in patients with PAH.

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