Preload-adjusted maximal power of right ventricle: contribution of end-systolic P-V relation intercept

2002 ◽  
Vol 283 (4) ◽  
pp. H1681-H1687 ◽  
Author(s):  
Patrick Segers ◽  
H. Alex Leather ◽  
Pascal Verdonck ◽  
Yuan-Yuan Sun ◽  
Patrick F. Wouters

To assess whether preload-adjusted maximal power (PAMP), which is calculated asW˙max/V[Formula: see text] (whereW˙max is maximal power and Ved is end-diastolic volume with β = 2) is an index of right ventricular (RV) contractility, we measured RV pressure (P) and volume (V) and pulmonary artery pressure and flow in 10 dogs at baseline and after inotropic stimulation. PAMP was derived from steady-state data, whereas the slope ( E es) and intercept (Vd) of the end-systolic P-V relationship were derived from data obtained during vena caval occlusion. Inotropic stimulation increased E es (from 0.96 ± 0.25 to 1.62 ± 0.28 mmHg/ml; P < 0.001) and Vd (from −3.0 ± 17.2 to 12.4 ± 10.8 ml; P < 0.05) but not PAMP (from 0.24 ± 0.10 to 0.36 ± 0.22 mW/ml2; P = 0.09). We found a strong relationship between the optimal β-factor for preload adjustment and Vd. A corrected PAMP, PAMPc= W˙max/(Ved − Vd)2, which incorporated the Vddependency, was sensitive to the inotropic changes (from 0.23 ± 0.12 to 0.54 ± 0.17 mW/ml2; P < 0.001) with a good correlation with E es( r = 0.88; P < 0.001).

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
KIRILL Malikov ◽  
MARINA Kirichkova ◽  
MARIA Simakova ◽  
NARECK Marukyan ◽  
OLGA Moiseeva

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Chronic thromboembolic pulmonary hypertension (CTEPH) leads to a progressive increase in pulmonary vascular resistance (PVR) and pulmonary artery pressure (PAP) with the development of severe dysfunction of the right heart and heart failure. Mortality for three years with an average pressure in the pulmonary artery (PA) of more than 50 mmHg is more than 90%. Balloon pulmonary angioplasty (BPA) has a significant advantage over other methods of surgical treatment, but it requires the determination of additional non-invasive markers of effectiveness. Transthoracic echocardiography (TTE) remains the main method for assessing the morphology and function of the heart. Purpose Compare different indicators reflecting the severity of CTEPH with TTE indicators before and after BPA. To evaluate the effectiveness of using BPA for the treatment of patients with CTEPH using routine TTE and speckle tracking mode. Materials and methods For 18 months 30 patients without concomitant cardiovascular pathology were subjected to several BPA sessions. Before treatment, 50% of patients belonged to the 3 CTEPH functional class (FC), 40% to 2 FC, 10% to 1 FC. The average number of sessions was 4.7 ± 1.3. Before the first BPA and after the last, all the patients were performed: six-minute walk test (6MWT, metres), Borg scale (in points), test for NT-proBNP (pg/ml); TTE with assessment of the right ventricle (RV) and left ventricle (LV) including areas of the right atrium (aRA, cm2), mean pulmonary artery pressure (PUPM,mmHg),RV free wall strain (GLSFW, %), RV free wall strain rate (GLSRFW, sm/sec), RV free wall postsystolic shortening (PSSFW, %), tricuspid annular plane systolic excursion (TAPSE, sm), tricuspid annulus systolic velocity (TASV, sm/sec). Results. Before the first BPA session, the 6MWT in the patient group averaged 315.9 ± 9.08 metres, after - 439.5 ± 11.45 m; the Borg from 5.4 ± 0.94 points decreased to 4 ± 1.01 points; NT-proBNP before the treatment was 1513 ± 13.01 pg/ml, after - 171 ± 6.09; according to TTE the ratio of RV/ LV before and after treatment was 1.31 ± 0.02 and 0.97 ± 0.04; aRA was 29.3 ± 4.87 and 22.3 ± 3.53 cm2; basal RV - 52 ± 5.11 and 44 ± 7.26 mm; PUPM decreased from 76.6 ± 7.65 to 31.3 ± 3.78 mmHg; GLSFW from -14.69 ± 2.33 came to 17.5 ± 3.45 %; GLSRFW with -0.9 ± 0.09 to -1.7 ± 0.11 cm/sec; TAPSE from 16.7 ± 1.87 to 18.2 ± 2.34 cm; TASV from 10.11 ± 1.45 to 12.25 ± 1.98 cm/s, PSSFW before treatment was -18.4 ± 1.2%, after treatment in 66% of patients disappeared, in 34% became an average of 17.4 ± 0.9% The distribution of STEPH FC has also changed. Conclusion. BPA leads to an improvement in the tolerance of physical activity, clinical indicators, and parameters of central hemodynamics in the pulmonary circulation, evaluated according to direct manometry, and leads to reverse remodeling of the RV in the long term. Performing a staged BPA leads to an improvement in the functional parameters of contractility of the RV.


2017 ◽  
Vol 136 (3) ◽  
pp. 262-265 ◽  
Author(s):  
Turgut Karabag ◽  
Caner Arslan ◽  
Turab Yakisan ◽  
Aziz Vatan ◽  
Duygu Sak

ABSTRACT CONTEXT: Obstruction of the right ventricular outflow tract due to metastatic disease is rare. Clinical recognition of cardiac metastatic tumors is rare and continues to present a diagnostic and therapeutic challenge. CASE REPORT: We present the case of a patient who had severe respiratory insufficiency and whose clinical examinations revealed a giant tumor mass extending from the right ventricle to the pulmonary artery. We discuss the diagnostic and therapeutic options. CONCLUSION: In patients presenting with acute right heart failure, right ventricular masses should be kept in mind. Transthoracic echocardiography appears to be the most easily available, noninvasive, cost-effective and useful technique in making the differential diagnosis.


2021 ◽  
Author(s):  
Janus Adler Hyldebrandt ◽  
Nikolaj Bøgh ◽  
Camilla Omann Christensen ◽  
Peter Agger

Abstract Background: Pulmonary hypertension is a significant risk factor in patients undergoing surgery. The combined effects of general anaesthesia and positive pressure ventilation can aggravate this condition and cause increased pulmonary blood pressures, reduced systemic blood pressures and ventricular contractility. Although perioperative use of inotropic support or vasopressors is almost mandatory for these patients, preference is disputed. In this study, we investigated the effects of norepinephrine and dobutamine and their ability to improve the arterio-ventricular relationship and haemodynamics in pigs suffering from chronic pulmonary hypertension.Method: Pulmonary hypertension was induced in five pigs by banding the pulmonary artery at 2–3 weeks of age. Six pigs served as controls. After 16 weeks of pulmonary artery banding, the animals were re-examined under general anaesthesia using biventricular conductance catheters and a pulmonary artery catheter. After baseline measurements, the animals were exposed to both norepinephrine and dobutamine infusions in incremental doses, with a stabilizing period in between the infusions. The hypothesis of differences between norepinephrine and dobutamine with incremental doses was tested using repeated two-way ANOVA and Bonferroni multiple comparisons post-test. Results: At baseline, pulmonary artery banded animals had increased right ventricular pressure (+39%, p=0.04), lower cardiac index (-23% p=0.04), lower systolic blood pressure (-13%, p=0.02) and reduced left ventricular end-diastolic volume (-33%, p=0.02). When incremental doses of norepinephrine and dobutamine were administered, the right ventricular arterio-ventricular coupling was improved only by dobutamine (p<0.05). Norepinephrine increased both left ventricular end-diastolic volume and left ventricular contractility to a greater extent (p<0.05) in pulmonary artery banded animals. While the cardiac index was improved equally by norepinephrine and dobutamine treatments in pulmonary artery banded animals, norepinephrine had a significantly greater effect on mean arterial pressure (p<0.05) and diastolic arterial pressure (p<0.05).Conclusion: While norepinephrine and dobutamine improved cardiac index equally, it was obtained in different manners. Dobutamine significantly improved the right ventricular function and the arterio-ventricular coupling. Norepinephrine increased systemic resistance, thereby improving arterial pressures and left ventricular systolic function by maintaining left ventricular end-diastolic volume.


2020 ◽  
Author(s):  
Song Jiyang ◽  
Wan Nan ◽  
Shen Shutong ◽  
Wei Ying ◽  
Cao Yunshan

Abstract Background: Right ventricular (RV) failure induced by sustained pressure overload is a major contributor to morbidity and mortality in several cardiopulmonary disorders. Reliable and reproducible animal models of RV failure are important in order to investigate disease mechanisms and effects of potential therapeutic strategies. To establish a rat model of RV failure perfectly, we observed the right ventricle and carotid artery hemodynamics characteristics in different degrees of pulmonary artery banding of rats of different body weights. Methods: Rats were subjected to 6 groups:control(0%, n=5)(pulmonary arterial banding 0%), PAB(1-30%, n=4)(pulmonary arterial banding1-30%), PAB(31-60%, n=6)(pulmonary arterial banding31-60%),PAB(61-70%, n=5)(pulmonary arterial bandin61-70%), PAB(71-80%,n=4)(pulmonary arterial banding71-80%), PAB(100%, n=3)(pulmonary arterial banding 100%). We measured the right ventricular pressure(RVP) by right heart catheterization when the pulmonary arterial was ligated. Results: The RVP gradually increased with increasing degree of banding, but when occlusion level exceeding 70%, high pressure state can be only maintained for a few minutes or seconds, and then the RVP drops rapidly until it falls below the normal pressure, which in Group F particularly evident.Conclusions: RVP have different reactions when the occlusion level is not the same, and the extent of more than 70% ligation is a successful model of acute right heart failure. These results may have important consequences for therapeutic strategies to prevent acute right heart failure.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Bhushan Sandeep ◽  
Xin Huang ◽  
Yuan Li ◽  
Xiaowei Wang ◽  
Long Mao ◽  
...  

Abstract Background To evaluate RV-PA coupling in post operative TOF patients with ventricular dilatation underwent for PVR and investigate the correlation between ventricular functions measuring Ea/Emax ratio using cardio magnetic resonance and the effect of surgical type at primary repair of TOF on coupling. Method RV-PA coupling was measured noninvasively by Ea/Emax ratio from CMRI and ECHO. From CMRI results the patients were divided in two groups, RV-PA coupling and RV-PA uncoupling. Ea/Emax ≤1 was considered for coupling patients and Ea/Emax > 1 for uncoupling patients. Results Ninety patients were uncoupled (Ea/Emax: 1.55 ± 0.46) and 45 were coupled (Ea/Emax: 0.81 ± 0.15). Out of 75 TAP repaired patients 60 were uncoupled RV-PV. In addition, higher pro-BNP is an important factor for uncoupled RV-PV (P = 0.001). CMR evaluation for right ventricular function between uncoupling and coupling were RVEDVi (196.65 ± 63.57 vs. 154.28 ± 50.07, P = 0.001), RVESVi (121.19 ± 51.47 vs. 83.94 ± 20.43, P = 0.001), RVSVi (67.19 ± 19.87 vs. 106.31 ± 33.44, P = 0.001), and RVEF (40.90 ± 8.73 vs. 54.63 ± 4.76, P = 0.001). The increased RVEDVi, RVESVi and RVSVi and decreased RVEF have significant correlation with Ea/Emax. Ea/Emax was also found positively correlated with RVEDVi (P = < 0.05, r = 0.35), RVESVi (P = < 0.001, r = 0.41) and negatively correlated with RVSVi (P = < 0.05, r = 0.22) and RVEF (P = < 0.05, r = 0.78). Conclusions Unfavorable RV-PA coupling is present in post operative TOF patients and it is affected by several factors. Our results explain a new concept of RV-PA interactions as a contributing mechanism for the observed decline in RV function.


2020 ◽  
pp. 039139882095421
Author(s):  
Tom Verbelen ◽  
Michael Halwes ◽  
Bart Meyns

Objectives: To assess the in vivo hemodynamic effects on the pressure overloaded right ventricle of RAS-Q® technology, the world’s first gas exchanger with a fully integrated compliance. Methods: In six acute in vivo trials RAS-Q was implanted in sheep between the pulmonary artery and left atrium. Right ventricular pressure overload was induced by pulmonary artery banding. Pressures and flows were recorded in baseline, moderate and severe pulmonary hypertension conditions. In one trial, RAS-Q was benchmarked against the pediatric Quadrox-i®. Results: With 1.00 and 1.17 L/min, RAS-Q delivered 31% and 39% of the total cardiac output in moderate and severe pulmonary hypertension, respectively. Pulmonary artery pressures and mean pulmonary artery pressure/mean arterial blood pressure ratio successfully decreased, implying a successful right ventricular unloading. Cardiac output was restored to normal levels in both pulmonary hypertension conditions. With both devices in parallel, RAS-Q provided three times higher flow rates and a 10 times higher pressure relief, compared to the pediatric Quadrox-i. Conclusion: A gas exchanger with a fully integrated compliance better unloads the right ventricle compared to a non-compliant gas exchanger and it can restore cardiac output to normal levels in cases of severe pulmonary hypertension.


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