Pulmonary Arterial Oxygen Saturation Research Articles

Large-bore aspiration thrombectomy versus catheter-directed thrombolysis for the treatment of pulmonary embolism: A retrospective case review from a community hospital

Objectives: This study aimed to assess acute outcomes following pulmonary embolism (PE) treatment with large-bore aspiration thrombectomy (LBAT) versus catheter-directed thrombolysis (CDT). Material and Methods: This single-center retrospective analysis included patients who received interventional therapy for acute PE from 2018 to 2022. The primary outcomes were changes in pre-procedural mean pulmonary artery pressure (PAP), heart rate (HR), oxygen saturation, and supplemental requirements following the procedure. Mean PAP was measured immediately post-procedure for LBAT patients and on postoperative day 1 (POD#1) for CDT patients. Results: A total of 48 patient cases were reviewed, 31 underwent LBAT and 17 underwent CDT. The majority of patients were female and most had intermediate-high-risk PE. No major bleeding events or device-related complications occurred. LBAT resulted in a significant decrease in average mean PAP immediately post-procedure (31.3 ± 9.0–21.4 ± 8.1 mmHg; P < 0.001). On POD#1, CDT resulted in a significant decrease in mean PAP (31.7 ± 11.2–25.6 ± 7.9 mmHg; P = 0.005). The decrease in mean PAP was greater in the LBAT versus CDT group (P < 0.05). Through POD#1, a similar reduction in average HR was observed between groups; however, a statistically significant reduction in HR was noted immediately post-procedure with LBAT and not with CDT. LBAT patients had a significant reduction in average supplemental oxygen requirements post-procedure. Conclusion: LBAT was associated with a greater reduction in mean PAP than CDT at an earlier post-procedural time point. LBAT may be advantageous over CDT due to rapid thrombus extraction; however, further studies with increased sample sizes are needed. Evidence-based medicine: Level of Evidence: Level 3, Local non-random sample.

Machine learning assisted feature identification and prediction of hemodynamic endpoints using computed tomography in patients with CTEPH.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare but potentially curable cause of pulmonary hypertension (PH). Currently PH is diagnosed by right heart catheterisation. Computed tomography (CT) is used for ruling out other causes and operative planning. This study aims to evaluate importance of different quantitative/qualitative imaging features and develop a supervised machine learning (ML) model to predict hemodynamic risk groups. 127 Patients with diagnosed CTEPH who received preoperative right heart catheterization and thoracic CTA examinations (39 ECG-gated; 88 non-ECG gated) were included. 19 qualitative/quantitative imaging features and 3 hemodynamic parameters [mean pulmonary artery pressure, right atrial pressure (RAP), pulmonary artery oxygen saturation (PA SaO2)] were gathered. Diameter-based CT features were measured in axial and adjusted multiplane reconstructions (MPR). Univariate analysis was performed for qualitative and quantitative features. A random forest algorithm was trained on imaging features to predict hemodynamic risk groups. Feature importance was calculated for all models. Qualitative and quantitative parameters showed no significant differences between ECG and non-ECG gated CTs. Depending on reconstruction plane, five quantitative features were significantly different, but mean absolute difference between parameters (MPR vs. axial) was 0.3mm with no difference in correlation with hemodynamic parameters. Univariate analysis showed moderate to strong correlation for multiple imaging features with hemodynamic parameters. The model achieved an AUC score of 0.82 for the mPAP based risk stratification and 0.74 for the PA SaO2 risk stratification. Contrast agent retention in hepatic vein, mosaic attenuation pattern and the ratio right atrium/left ventricle were the most important features among other parameters. Quantitative and qualitative imaging features of reconstructions correlate with hemodynamic parameters in preoperative CTEPH patients-regardless of MPR adaption. Machine learning based analysis of preoperative imaging features can be used for non-invasive risk stratification. Qualitative features seem to be more important than previously anticipated.

Invasive Hemodynamic and Vasoreactivity Testing with Inhaled Iloprost in Children with Pulmonary Arterial Hypertension Associated with Congenital Heart Defects

Objective: Invasive hemodynamic evaluation and acute vasoreactivity testing are recommended in the diagnosis of pulmonary arterial hypertension (PAH), but their clinical role in children with PAH associated with congenital heart defects (CHD) is unclear. This study aims to investigate acute hemodynamic responses to inhaled iloprost, and its role in prognosis in children with PAH-CHD. Methods: A retrospective analysis was conducted on 83 pediatric patients with PAH-CHD in whom invasive hemodynamics were evaluated before and after a single inhaled dose of iloprost at a single center between 2010 and 2022. Details of the CHD corrective operation, medical treatment, and outcome for each patient were obtained via medical records or telephone contact. A composite endpoint of all-cause death, admission for worsening heart failure during follow-up, and event-free survival was defined, and risk factors associated with this composite endpoint were analyzed. Results: The patient age was (11.3 ± 4.6) years, and 60 (72.3%) were female. Fifty-nine (71.1%) patients were diagnosed with Eisenmenger syndrome. After iloprost inhalation, mean pulmonary artery pressure decreased from (78.2 ± 11.5) to (72.3 ± 13.2) mmHg (P < 0.001), and pulmonary vascular resistance index (PVRI) decreased from (18.0 ± 7.9) to (14.5 ± 8.1) WU·m2 (P < 0.001). A total of 38 (45.8%) patients had a positive response, defined as a PVRI decrease >25% with stable systemic pressure. Thirty-seven (44.6%) patients underwent a corrective CHD operation at a median of 24 d after hemodynamic evaluation. Nine patients died, and 15 met the composite endpoint during a follow-up period of 5.4 (3.8, 8.8) years. Five-year event-free survival estimates were 96.7% (95% confidence interval: 90.3%–100%) in patients with a positive response, and 82.8% (95% confidence interval: 71.7%–94.5%) in patients with a non-positive response (log-rank P = 0.012). A positive PVRI response and higher pulmonary arterial oxygen saturation after iloprost inhalation, lower baseline brain natriuretic peptide, and PAH-targeted therapy at follow-up were significantly associated with a favorable clinical outcome. A positive acute vasoreactivity testing response and PAH-targeted therapy at follow-up were independent predictors of outcome in multivariate Cox analysis. Conclusions: Acute inhalation of iloprost can lead to a significant decrease in hemodynamic parameters. Responsiveness to inhaled iloprost is associated with better outcomes and can be a valuable predictor of outcomes.

Prognostic Value of Pulmonary Artery Oxygen Saturation in Pulmonary Embolism Requiring Endovascular Intervention

This retrospective study evaluates the prognostic value of pulmonary artery oxygen saturation (PA O2) among patients who undergo mechanical intervention for pulmonary embolism (PE). Patients who died within 90 days had less PA O2, and a greater percentage of patients with a PA O2 of <50 died within 90 days of intervention. Regression analysis revealed an association of PA O2 with mortality that held true despite accounting for Pulmonary Embolism Severity Index (PESI) score and type of endovascular intervention. Receiver operator curve testing revealed PA O2 <50% to be inferior to PESI score but superior to Bova score in predicting mortality after mechanical PE intervention, with the combination of PA O2 <50% and PESI outperforming PESI and PA O2 in predicting mortality. Our pilot evaluation suggests preintervention PA O2 <50% to be associated with increased risk of all-cause mortality and may help identify patients at greatest risk of deterioration.

P61: Novel use of newer intravascular ambulatory systemic ventricular assist devices as a bridging strategy for cardiogenic shock with pulmonary hypertension in patients with complex congenital cardiac conditions

Background: Cardiogenic shock [CS] in patients with failing systemic ventricles is associated with high mortality. Suitable patients maybe successfully bridged using newer intravascular ambulatory left ventricular assist devices [Impella 5.5, Abiomed, Danvers, MA] as a bridge to transplantation. We report our successful experience with two such patients. Methods: Between January 2022 and January 2023, 2 patients underwent trans-axillary artery placement of LV Impella 5.5 for CS as a bridge to heart transplant. Both these patients had previously undergone a Senning operation for transposition of the great arteries, and presented with failing systemic ventricle with pulmonary hypertension. Results: Two patients [patient 1: 36 years, patient 2: 38 years] presented to our unit with cardiogenic shock. They underwent trans-axillary artery placement of LV Impella 5.5 into the systemic ventricle for CS as a bridge to decision for high pulmonary vascular resistance [PVR]. Heart and lung transplantation was considered, but the patients declined and opted to pursue strategy for heart transplant alone. Following 30 and 50 days on impella 5.5 support in patients 1 and 2 respectively, along with intravenous diuretics and milrinone 0.25mcg/kg/min, there was reversal of pulmonary hypertension [Table-1]. Both patients underwent successful redo-sternotomy and heart transplantation. Second patient required 48-hours of extra-corporeal membrane oxygenator [ECMO] support for primary graft dysfunction, increased immunosuppression for grade 2 rejection, and temporary renal replacement therapy. Both patients recovered and were discharged home. Conclusions: We report successful outcomes in these two patients who had previously undergone complex congenital heart surgery, and had presented to us in cardiogenic shock with failing systemic ventricles and severe pulmonary hypertension, which hitherto would have precluded cardiac transplantation alone. Utilization of Impella 5.5 for cardiogenic shock in these patients facilitated successful reversal of pulmonary hypertension and therefore, a successful cardiac transplantation without resorting to durable VAD placement or heart-lung transplantation in this difficult cohort of patients. Furthermore, impella 5.5 placement helped avoid femoral ECMO completely, with its inherent problems of immobility, bleeding, infections, limb ischemia, and muscle wasting, and greatly facilitated early ambulation and rehabilitation while awaiting a suitable organ. Table 1. - Pre transplant hemodynamics in both patients PAS PAD PAM PCWP TPG PVR RA CI CO PA Sat P1 Baseline 80 50 60 38 22 10 22 1.1 2.2 34% P1 Day-30 impella 45 20 28 18 10 2 7 2.7 5 59% P2 Baseline 88 50 64 41 23 4.8 18 3 4.7 58% P2 Day-50 impella 57 26 36 16 20 2.5 7 4 7.3 74% PAS/D/M: pulmonary artery systolic/diastolic/mean pressures; PCWP: pulmonary capillary wedge pressure; TPG: trans pulmonary gradient; RA: right atrial pressure. All in mmHg. PVR: pulmonary vascular resistance in wood units CI: cardiac index in liters/minute/square meter body surface area; CO: cardiac output in liters/minute; PA sat: pulmonary artery oxygen saturation

Right and left ventricular blood pool T2 ratio on cardiac magnetic resonance imaging correlates with hemodynamics in patients with pulmonary hypertension

ObjectivesOur objective is to compare the right/left ventricular blood pool T1 ratio (RVT1/LVT1), and right/left ventricular blood pool T2 ratio (RVT2/LVT2) on Cardiac Magnetic Resonance Imaging (CMR) between patients with pulmonary hypertension (PH) and normal controls, to analyze the correlation of RVT1/LVT1, RVT2/LVT2 and hemodynamics measured with right heart catheterization (RHC) in patients with PH.MethodsForty two patients with PH and 40 gender-and age-matched healthy controls were prospectively included. All patients underwent RHC and CMR within 24 h. The right and left ventricular blood pool T1 and T2 values were respectively measured, and RVT1/LVT1 and RVT2/LVT2 between the PH group and the healthy control were compared. Meanwhile, the correlation between RVT1/LVT1, RV/LVT2 ratio and hemodynamic parameters in patients with PH respectively was analyzed.ResultsIn the control group, RVT2 was significantly lower than LVT2 (t = 6.782, p < 0.001) while RVT1 also was lower than LVT1 (t = 8.961, p < 0.001). In patients with PH, RVT2 was significantly lower than LVT2 (t = 9.802, p < 0.001) while RVT1 was similar to LVT1 (t = − 1.378, p = 0.176). RVT2/LVT2 in the PH group was significantly lower than that in the control group (p < 0.001). RVT1/LVT1 in PH patients increased in comparison with the control group (p < 0.001). RVT2/LVT2 negatively correlated with pulmonary vascular resistance (r = − 0.506) and positively correlated with cardiac index (r = 0.521), blood oxygen saturation in Superior vena cava, right atrium, right ventricle and pulmonary artery (r = 0.564, 0.603, 0.648, 0.582).ConclusionsRVT2/LVT2 on T2 mapping could be an additional CMR imaging marker that may assist to evaluate the severity of PH.

Severity of functional tricuspid regurgitation is associated with mortality in patients with pulmonary hypertension in long-term follow-up.

Pulmonary hypertension (PH) is a hemodynamic and pathophysiologic state present in many cardiovascular, respiratory, and systemic diseases. PH is considered to have a higher risk of cardiovascular events and mortality. The most common type of functional tricuspid regurgitation (FTR) is associated with PH. The aim of this study was to evaluate the association between FTR severity and mortality in PH in western China. This is a retrospective analysis in PH patients and all patients underwent right-heart catheterization (RHC) for hemodynamic measurements. The FTR severity was determined according to the guidelines. Uni- and multivariate analyses were used to identify risk factors for mortality. From 2015 to 2021, 136 patients with PH with a median age of 50 years (interquartile range [IQR]: 35-64 years). During 26-month median follow-up (mean 27.7 ± 15.1 months), 40 (29.2%) patients died (mean after 21.7 ± 14.1 months). In the univariate Cox regression analysis, World Health Organization functional class (WHO FC) III/IV, elevated B-type natriuretic peptide, pulmonary vascular resistance (≥16.2 Wood units), pulmonary artery oxygen saturation, severe FTR and right ventricular diameter/left ventricular diameter (≥0.62) were significantly associated with mortality. In the multivariate Cox regression analysis, severe FTR, WHO FC III/IV, and right ventricular end-diastolic pressure (RVEDP) were risk factors for mortality. Severe FTR at baseline was strongly associated with mortality in both precapillary and postcapillary PH patients, independent of the other risk factors as RVEDP,HO FC III/IV,optimal pulmonary arterial hypertension targeted therapy.

Detecting and Quantifying Residual Intracardiac Shunts Using Oximetric Step-Up Methods: A Prospective Observational Study.

Background & aims Intracardiac shunts are abnormal channels of blood circulation within the heart that develop eitheras an additional blood flow pathway or as a replacement for the normal channels of blood circulation. They are the commonest types of congenital heart defects. Various methods are available in the present times to identify, localize or quantify left-to-right intracardiac shunts. Methods may vary in sensitivity, indicators, or types of equipment available. One such method used in almost all cardiac centers for a long time has been oximetry runto detect step-up differences in oxygen saturation values. In the oximetry runthe main approach to detect and estimate the left-to-right (L-->R) shuntsrequires the oxygen concentration expressed as a proportion of saturation to be evaluated in blood samples which are obtained from the right atrium (RA) and pulmonary artery (PA), respectively. A left-to-right shunt can be considered if there is a significant increase (step-up) in bloodsaturation. A significant step-up is defined as a substantial rise in blood oxygen content or saturation that is higher than normal values. Methods Using a prospective observational design, this article investigates the application of the step-up method in detecting intracardiac shunts. The study was conducted between 2021 and 2022 on 35 pediatric cardiac patients (males/females, 24/11) diagnosed with post-tricuspid shunts. The pulmonary artery and right atrium were sampled before and after cardiopulmonary bypass surgery and analyzed using a blood gas test. As a result, nearly 91% of the patients had a saturation below 8%. However, the difference between PA oxygen saturation (SO2) & RASO2 before and after surgery was significant. As a result, the difference in O2 saturation helped detect the residual ventricular septal defect (VSD) after the surgery. Results There were no deaths or complications in this study. There were no re-interventions for post-tricuspid shunt surgery, though one patient had a step-up of >15% and residual VSD status was moderate to large on two-dimensional (2D) echocardiography. Conclusion A combination of physical findings, chest radiography, electrocardiogram (ECG), and echocardiography is routinely done for all these patients undergoing pediatric cardiac surgery. Echocardiography can detect the occurrence of shunt but does not calculate the shunt ratio. Transesophageal or epicardial echocardiography is the standard of care but has its limitations like perception difference between the operating surgeon and the person performing echocardiography. In this study, we have added an oximetry analysis of blood-gas samples before and after surgery and compared it to 2D echocardiography to test the validation of oximetry in isolation and comparison to 2D echocardiography.

Effects of Moderate Intensity Circuit Exercise Programme on the Blood Oxygen Saturation and Pulmonary Function of People Living With HIV

Introduction: Impaired pulmonary function and arterial oxygen (O2) saturation are among the symptomatic changes in people living with HIV (PLWH), associated with progression of HIV disease and anti-retroviral therapy (ART). Exercise has been considered an important adjuvant therapy for health promotion and improving the pulmonary function of PLWH. However studies are lacking on the effects circuit exercise training on o2 saturation and pulmonary function of PLWH. Objective: This study determined the effect of moderate intensity circuit exercise programme on the O2 saturation and pulmonary function of PLWH. Methods: The study design was a pretest-posttest randomized controlled design. A total of 120 participants were recruited from the HIV clinic of a teaching hospital. Fish bowl method was used to randomize the participants to control group or exercise group. Moderate intensity (50 – 75% MHR) circuit exercise programme was administered to the participants 3 times a week between 30-60 minutes per session for 8 weeks. Pulse Oximeter and hand held spirometer were used to measure the oxygen saturation and some pulmonary functions respectively. Measurement were taken at baseline and at 8-week. Descriptive statistics of mean, standard deviation and percentages were used to summarize demographic data. Paired sample t-test and Independent sample t-test determined the mean difference within the groups and between the groups respectively. Alpha level was set at P&lt;0.05. Results: There was significant difference in the mean score of O2 saturation and pulmonary function within the exercise group after 8-week exercise intervention. There was significant difference in the mean score of O2 saturation and pulmonary function between the control group and exercise group after 8-week exercise intervention. Conclusion: An 8-week circuit exercise programme brought about improvement in O2 saturation and pulmonary function of PLWH. Circuit exercise can be effectively employed to improve lung function and ameliorate the exercise hypoxemia associated with decreased O2 saturation in PLWH.

Mathematical modelling of oxygenation under veno-venous ECMO configuration using either a femoral or a bicaval drainage

BackgroundThe bicaval drainage under veno-venous extracorporeal membrane oxygenation (VV ECMO) was compared in present experimental study to the inferior caval drainage in terms of systemic oxygenation.MethodTwo mathematical models were built to simulate the inferior vena cava-to-right atrium (IVC → RA) route and the bicaval drainage-to-right atrium return (IVC + SVC → RA) route using the following parameters: cardiac output (QC), IVC flow/QC ratio, venous oxygen saturation, extracorporeal pump flow (QEC), and pulmonary shunt (PULM-Shunt) to obtain pulmonary artery oxygen saturation (SPAO2) and systemic blood oxygen saturation (SaO2).ResultsWith the IVC → RA route, SPAO2 and SaO2 increased linearly with QEC/QC until the threshold of the IVC flow/QC ratio, beyond which the increase in SPAO2 reached a plateau. With the IVC + SVC → RA route, SPAO2 and SaO2 increased linearly with QEC/QC until 100% with QEC/QC = 1. The difference in required QEC/QC between the two routes was all the higher as SaO2 target or PULM-Shunt were high, and occurred all the earlier as PULM-Shunt were high. The required QEC between the two routes could differ from 1.0 L/min (QC = 5 L/min) to 1.5 L/min (QC = 8 L/min) for SaO2 target = 90%. Corresponding differences of QEC for SaO2 target = 94% were 4.7 L/min and 7.9 L/min, respectively.ConclusionBicaval drainage under ECMO via the IVC + SVC → RA route gave a superior systemic oxygenation performance when both QEC/QC and pulmonary shunt were high. The VV-V ECMO configuration (IVC + SVC → RA route) might be an attractive rescue strategy in case of refractory hypoxaemia under VV ECMO.

Early outcomes of fenestrated intra-extracardiac Fontan procedure: Insights, experiences, and expectations.

Intraextracardiac Fontan procedure (FP) aimed to combine the advantages of lateral tunnel and extracardiac conduit modifications of the original technique. Herein, we present our early outcomes in patients with intraextracardiac fenestrated FP. A retrospective analysis was performed to evaluate intraextracardiac fenestrated Fontan patients between 2014 and 2021. Seventeen patients were operated on with a mean age and body weight of 9.1 ± 5.5 years and 28.6 ± 14.6 kg. Sixteen patients (94%) were palliated as univentricular physiology with hypoplasia of one of the ventricles. One patient (6%) with well-developed two ventricles with double outlet right ventricle and complete atrioventricular septal defect had straddling of the chordae prohibiting a biventricular repair. All of the patients had cavopulmonary anastomosis before Fontan completion, except one case. Fenestration was performed in all cases. Postoperative mean pulmonary artery pressures and arterial oxygen saturation levels at follow-up were 10 ± 2.4 mmHg and 91.3 ± 2.7%, respectively. Mean duration of pleural drainage was 5.4 ± 2.3 days. All of the fenestrations are patent at a mean follow-up period of 4.8 ± 7.7 years, except one case. Any morbidity and mortality were not encountered. Early outcomes of intraextracardiac fenestrated FP are encouraging. This procedure may improve the results in a patient population who should be palliated as univentricular physiology, especially in cases with complex cardiac anatomy.

Fatal pulmonary tumour thrombotic microangiopathy in patient with ovarian adenocarcinoma: review and a case report

BackgroundPulmonary tumour thrombotic microangiopathy (PTTM) is a fatal disease in which tumour cells embolize to the pulmonary vasculature leading to pulmonary hypertension and right heart failure. Early diagnosis is essential for timely treatment which can reduce intimal pulmonary vascular proliferation and prolong survival, improve the symptoms. Due to rare occurrences and no clear diagnostic guidelines the disorder usually is found post-mortem. We present a review of this rare disease and a case of post-mortem diagnosed pulmonary tumour thrombotic microangiopathy in a young female.Case presentation51 years old woman presented with progressively worsening dyspnea, right ventricular failure signs and symptoms. Computerized tomography denied pulmonary embolism. 2D transthoracic echocardiography demonstrated right ventricle dilatation and dysfunction, severely increased systolic pulmonary pressure. Right heart catheterization revealed pre-capillary pulmonary hypertension with mean pulmonary artery pressure of 78 mmHg, pulmonary wedge pressure of 15 mmHg, reduced cardiac output to 1.78 L/min with a calculated pulmonary vascular resistance of 35 Wood units, and extremely low oxygen saturation (26%) in pulmonary artery. Because of worsening ascites, pelvic magnetic resonance imaging was performed, tumours in both ovaries were diagnosed. Due to the high operative risk, detailed tumour diagnosis surgically was not established. The patient developed progressive cardiorespiratory failure, unresponsive to optimal heart failure drug treatment. A postmortem morphology analyses revealed tumorous masses in pre-capillary lung vessels, right ventricle hypertrophy, ovary adenocarcinoma.ConclusionsAn early diagnosis of PTTM is essential. Most cases are lethal due to respiratory failure progressing rapidly. Patients with a history of malignancy, symptoms and signs implying of PH should be considered of having PTTM. If detected early enough, combination of chemotherapy with specific PH therapy is believed to be beneficial in reducing intimal proliferation and prolonging survival, along with improving the symptoms.

M13. Stenting of right ventricular outflow tract as palliation for patient with right ventricular outflow tract obstruction with ventricular shunt physiology: a systematic review and meta-analysis

Abstract Aims Right ventricular outflow tract (RVOT) stenting is emerging as an effective alternative to surgical palliation in selected patients. We aim to assess the outcome of RVOT stenting in patients suffered from RVOT obstruction with ventricular shunt physiology such as tetralogy of Fallot (ToF) and other type of lesions, also to compare its clinical outcomes with modified Blalock-Taussig shunt (mBTS) procedure. Method and Results A systematic review and meta-analysis was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. We systematically searched the relevant studies from date of inception to June 2021. Outcomes of interest were pulmonary artery (PA) growth and oxygen saturation after palliation. Eleven retrospective studies (384 patients) were included for qualitative analysis, and four studies (193 patients) were eligible for meta-analysis. From our study, RVOT stenting can be accomplished safely and effectively in severe cyanosis or high risk patients with ToF physiology. Right PA z-score and oxygen saturation post RVOT stenting was significantly higher compared with post mBTS (MD 0.50; 95% CI 0.06 – 0.93, p = 0.03 and MD 3.46; 95% CI 1.42 – 5.49, p = 0.0009 respectively). Our analysis shows no significant difference of left PA z-score after palliation between two groups (MD -0.05; 95% CI -0.89 – 0.79, p = 0.90). Conclusion RVOT stenting effectively improves oxygen saturation and promotes proper pulmonary artery growth in patients with ToF physiology. The larger and randomized-controlled studies are required to better evaluate the efficacy of RVOT stenting and its superiority compared to mBTS.

Role of cardiac magnetic resonance in stratifying the prognosis of patients with pulmonary arterial hypertension

Abstract Background Pulmonary arterial hypertension (PAH) is a rare disease characterized by a complex remodeling of heart structures. Cardiac magnetic resonance (CMR) is the gold standard for a non-invasive evaluation of right ventricle (RV) volumes and mass. Purpose To define the relationship between clinical, functional, biochemical, haemodynamic and CMR parameters and survival in patients with PAH. Methods Consecutive patients with PAH referred to our centre underwent clinical, functional, brain natriuretic peptide (BNP) plasma levels, haemodynamic and CMR evaluation. All patients were treated according to current guidelines. Univariate Cox analysis for survival was performed. Parameters with a p-value &amp;lt;0.1 at the univariate analysis were included in the multivariate analysis. Results One hundred forty-seven patients with PAH (mean age 49±17 years, 69% female) were included in the study. Etiology of PAH was: idiopathic/heritable (49%), associated with connective tissue disease (19%), congenital heart disease (12%), portal hypertension/HIV infection (12%) and pulmonary veno-occlusive disease (8%). Thirty-six patients died during follow-up. Parameters significantly associated with mortality at the univariate analysis were age [Hazard Ratio (95% Confidence Interval): 1.043 (1.020–1.067); p&amp;lt;0.001], six-minute walk test (6MWT) [HR: 0.995 (0.993–0.998); p&amp;lt;0.001], WHO-functional class [HR: 2.489 (1.025–6.041); p=0.044], idiopathic-heritable-congenital heart disease aetiology [HR: 0.182 (0.085–0.389); p&amp;lt;0.001], connective tissue disease aetiology [HR: 2.274 (1.099–4.704); p=0.027], pulmonary veno-occlusive disease aetiology [HR: 5.864 (2.328–14.773); p&amp;lt;0.001], right atrial pressure [HR: 1.098 (1.032–1.169); p=0.003], pulmonary artery oxygen saturation [HR: 0.947 (0.921–0.975); p&amp;lt;0.001], BNP levels [HR: 2.214 (1.213–4.039); p=0.010], RV wall thickness [HR: 0.633 (0.399–1.006); p=0.053], RV end diastolic volume [HR: 1.012 (1.003–1.021); p=0.007], RV end systolic volume [HR: 1.014 (1.003–1.024); p=0.011]. Parameters independently associated with mortality at the multivariate analysis were age [HR: 1.035 (1.006–1.064); p=0.018], idiopathic-heritable-congenital heart disease aetiology [HR: 0.355 (0.146–0.860); p=0.022], pulmonary veno-occlusive disease aetiology [HR: 3.129 (1.071–9.143); p=0.037], pulmonary artery oxygen saturation [HR: 0.953 (0.919–0.989); p=0.011], RV wall thickness [HR: 0.527 (0.300–0.927); p=0.026], RV end systolic volume [HR: 1.016 (1.003–1.029); p=0.014]. Conclusion RV wall thickness and RV end-systolic volume are associated with prognosis in patients with PAH independently from clinical and haemodynamic characteristics. These parameters may be used in the overall risk stratification of PAH patients. Funding Acknowledgement Type of funding sources: None.

Fontan procedure in patients with preoperative mean pulmonary artery pressure over 15 mmHg.

Several factors affect the long-term outcome of Fontan procedure, but a high pulmonary artery pressure is still one of the most important limitation for proceeding to a Fontan circulation. Herein, we present our experience in Fontan patients with high preoperative pulmonary artery pressures. A retrospective analysis was performed to evaluate Fontan patients with a preoperative pulmonary artery pressure >15 mmHg between 2009 and 2020. Sixteen patients were operated on with a mean preoperative pulmonary artery pressure of 17.5 ± 2.1 mmHg. Mean age at the time of Fontan procedure was 7.8 ± 5.6 years. All the patients had stage 2 cavopulmonary anastomosis before Fontan completion, with a mean interstage period of 4 ± 2.6 years. Fontan completion was achieved with a polytetrafluorethylenetubular conduit, two of which were intra-extracardiac. Fenestration was performed in five(31%) cases. Postoperative pulmonary artery pressures and arterial oxygen saturation levels were 11.2 ± 2.8 and 97.8 ± 2 mmHg, respectively. Mean duration of pleural drainage was 3.9 ± 5.3 days. Any morbidity and mortality were not encountered during a mean follow-up period of 4.8 ± 7.7 years. The midterm results of stage 3 Fontan completion in patients with pulmonary artery >15 mmHg are encouraging. Not only the mean pulmonary artery pressure but also the pulmonary vascular resistance may be helpful in order to identify the high risk patients before Fontan completion.

Safety of the Inari FlowTriever device for mechanical thrombectomy in patients with acute submassive and massive pulmonary embolism and contraindication to thrombolysis

Objectives: This report evaluates the safety of percutaneous mechanical thrombectomy with the Inari FlowTriever System (Inari Medical, Irvine, California) for the treatment of acute massive/submassive pulmonary embolism (PE) specifically in therapeutically anticoagulated patients with contraindication to thrombolysis. Material and Methods: A single-center retrospective chart review was performed on patients with contraindication to thrombolysis and massive/submassive PE who underwent FlowTriever thrombectomy between 2017 and 2019. Primary outcomes included procedure or device-related complications within 30 days of discharge. Secondary outcomes included technical and clinical success defined by improvement in mean pulmonary artery pressure (PAP), oxygen saturation, and heart rate. Results: Thirteen patients with contraindication to thrombolysis received FlowTriever thrombectomy with technical success achieved in all cases. Zero major or minor adverse events, technical complications, delayed procedure-related complications, or deaths within 30 days of hospital discharge occurred. Mean PAP decreased significantly by 19.1% (32.5 ± 13.3 mmHg to 26.3 ± 12.4 mmHg; P = 0.0074, 95% confidence interval (CI) 2.0–10.5 mmHg). Oxygen saturation improved post-procedure (increased 3.9 ± 3.8%; p = 0.0032, 95% CI 1.6– 6.1%) as did heart rate (decreased 22.2 ± 17.0 bpm; P &lt; 0.001, 95% CI 11.9–32.4 bpm). Anticoagulation was maintained throughout every procedure and all patients were closed with purse-string suture only. Conclusion: FlowTriever mechanical thrombectomy appears safe for acute PE in therapeutically anticoagulated patients with contraindications to thrombolytic therapy. These patients may experience immediate hemodynamic improvements similar to those reported in other studies. Further data are needed to prospectively evaluate long-term safety in this population.

Abstract 17500: A Crisis of the Heart

A 59 year old female with past medical history of metastatic neuroendocrine tumor without cardiac involvement was admitted for transarterial catheter embolization (TACE) procedure of liver lesions. During the TACE procedure, she developed hypertensive urgency treated with intravenous beta blocker therapy and continuous octreotide for carcinoid reaction. The following day she developed acute pulmonary edema and labile blood pressures requiring low dose norepinephrine. Octreotide infusion was up-titrated to 500 mcg/hour with concern for carcinoid crisis. On physical exam, she was tachycardic and regular without notable murmurs or extra cardiac sounds, no elevated jugular venous distension, and no lower extremity edema. She had bilateral crackles on pulmonary exam and was diaphoretic and delirious. There were sub-millimeter lateral ST- segment elevations on her electrocardiogram but her troponin levels were elevated to 14 ng/dL. Point of care cardiac ultrasound demonstrated severely impaired left ventricular systolic function without regional wall motion abnormalities. Coronary angiogram revealed diffuse coronary vasospasm and elevated left ventricular end-diastolic pressure. On right heart catheterization, she had elevated filling pressures, pulmonary arterial oxygen saturation of 25%, and cardiac index of 1.42 L/min/m2. Our patient was diagnosed with cardiogenic shock secondary to octreotide mediated coronary vasospasm causing diffuse myocardial injury. Continued multidisciplinary discussions were needed to determine appropriate vasopressor and inotropic agent use to support cardiac function without triggering further hormonal dysregulation during carcinoid crisis. Her cardiac function eventually improved with left ventricular Impella support and gradual down-titration of octreotide dose. Norepinephrine, epinephrine, and phenylephrine were avoided in favor of vasopressin, and dobutamine was switched to milrinone to prevent further sympathetic activation. She was able to wean off Impella and pressor support and had improvement of her left ventricular function on repeat echocardiography one month later. She has not had recurrence of heart failure symptoms and continues to follow up with oncology via tele-visits.

Acute hemodynamic effects of iatrogenic inter-atrial shunts after percutaneous edge-to-edge mitral valve repair

Abstract Background Implantable interatrial shunt devices improve pulmonary vascular function in patients with heart failure by transferring richly oxygenated blood to the right heart. Whether iatrogenic atrial septum defects (iASDs) after percutaneous edge-to-edge mitral valve repair (pMVR) are also associated with beneficial hemodynamic effects has not been investigated. Methods We consecutively enrolled patients with relevant functional (FMR) and degenerative mitral regurgitation (DMR) scheduled for pMVR. Invasive hemodynamic assessments were performed prior to and immediately after the procedure. Results 97 consecutive patients (75.4±9.1 years; 58% female) were prospectively included, 65 (66%) presented with relevant FMR. At baseline when compared to the DMR group, FMR was associated with worse left ventricular (LV) function (LV ejection fraction: 39 vs. 49%; p=0.001), higher NT-proBNP levels (7404 vs. 5214 pg/mL; p=0.023), worse renal function (serum creatinine: 1.7 vs. 1.3 mg/dL; p=0.019), and higher usage of spironolactone (68 vs. 42%; p=0.018) and sacubitril/valsartan (33 vs. 0%; p&amp;lt;0.001). Following pMVR, cardiac output (CO) and systemic blood flow (Qs) increased significantly (CO: 4.6 to 5.5 L/min; p&amp;lt;0.001; Qs: 4.9 to 5.8 L/min; p=0.002), with more pronounced changes in the FMR subgroup (ΔCO: 1.0 vs. 0.6 L/min; Figure 1A; ΔQs: 1.2 vs. 0.1 L/min), when compared to DMR. Pulmonary blood flow (Qp) increased by 26% (4.3 to 5.4 L/min; p=0.008), accompanied by a raise in pulmonary artery (PA) oxygen (O2) saturation from 73 to 77% (p&amp;lt;0.001). Arterial O2 saturation levels remained unchanged (98.3 to 98.7%; p=0.165), confirming no significant changes in systemic oxygenation. These changes were associated with a slight decline in pulmonary vascular resistance (PVR: 250 to 225 dynes*sec/cm5; p=0.369, Figure 1B), and a tendency towards improvement of pulmonary compliance (PAC: 3.6 to 4.0 mL/mmHg; p=0.414). Conclusions Invasively measured CO, Qs, Qp, and mixed-venous PA O2 saturation increased immediately after pMVR, alongside with potentially beneficial effects on pulmonary vasculature with marked improvements in PVR and PAC. These changes were more pronounced in the FMR subgroup. Further studies are required to assess long-term hemodynamic effects and underlying mechanisms of persistent iASDs on pulmonary vascular function. Figure 1. Invasive hemodynamics Funding Acknowledgement Type of funding source: None

Relationship between pulmonary vascular dysfunction and prognosis of patients with acute lung injury

To investigate the effect of pulmonary vascular dysfunction in the prognosis of patients with acute lung injury (ALI). Patients with ALI who underwent pulmonary artery catheterization in the department of critical care medicine of Wuhan NO.1 Hospital from June 2017 to June 2019 were enrolled. The general information, clinical and hemodynamic indexes [central venous pressure (CVP), pulmonary artery wedge pressure (PAWP), pulmonary artery systolic pressure (sPAP), pulmonary artery diastolic pressure (dPAP), mean pulmonary artery pressure (mPAP), cardiac index (CI)], acute physiology and chronic health evaluation II (APACHE II) score, arterial blood gas parameters [pH, partial pressure of oxygen (PO2), partial pressure of carbon dioxide (PCO2), oxygenation index (PaO2/FiO2)], whether there was shock or not; ventilator parameters [platform pressure (Plat), positive end-expiratory pressure (PEEP)], etc. were recorded. Pulmonary artery oxygen saturation, pulmonary vascular function indexes [transpulmonary potential gradient (TPG) and pulmonary vascular resistance index (PVRi)] were calculated. The relationship between TPG, PVRi and mechanical ventilation time, the length of intensive care unit (ICU) stay, cardiovascular days and 60-day mortality were analyzed in patients with different prognosis of 60-day and whether the TPG increased (≥ 12 mmHg was defined as elevated TPG, 1 mmHg = 0.133 kPa). A total of 65 patients were included in the study, including 30 males and 35 females; aged (48.9±15.2) years old. Forty-eight cases survived in 60-days, 17 died, and the 60-day mortality was 26.2%. At the baseline, there were no significant differences in cardiopulmonary function measurements, such as CVP, sPAP, dPAP, PAWP, CI, etc. between the two groups of patients with different prognosis. The APACHE II score, shock ratio, TPG and PVRi of the death group were significant higher than those of the survival group [APACHE II: 34±9 vs. 28±11, shock: 52.9% vs. 25.0%, TPG (mmHg): 16.2±1.9 vs. 14.6±2.1, PVRi (kPa×s×L-1): 31.8±4.2 vs. 29.7±3.5, all P < 0.05]. The 60-day mortality of 47 patients with TPG ≥ 12 mmHg was significantly higher than that of 18 patients with TPG < 12 mmHg (34.0% vs. 5.6%), and the mechanical ventilation time and the length of ICU stay were also significantly longer (days: 17±9 vs. 11±8, 16±5 vs. 12±5), and the cardiovascular days also increased significantly (days: 23±7 vs. 18±6), and the differences were statistically significant (all P < 0.05). Pearson correlation analysis showed that PVRi was significantly correlated with mechanical ventilation time, the length of ICU stay and cardiovascular days (r1 = 0.317, P1 = 0.030; r2 = 0.277, P2 = 0.005; r3 = 0.285, P3 = 0.002). In the individual multivariate Logistic regression model, the highest PVRi was an independent risk factor for the 60-day mortality [odds ratio (OR) = 30.5, 95% confidence interval was 20.4-43.1, P = 0.023]. Pulmonary vascular dysfunction is common in ALI patients and is independently associated with adverse outcomes.

Impact of stent of ductus arteriosus and modified Blalock-Taussig shunt on pulmonary arteries growth and second-stage surgery in infants with ductus-dependent pulmonary circulation.

IntroductionDucts-dependent pulmonary circulation is spectrum of congenital heart diseases that need urgent intervention to augment pulmonary blood. Systemic to pulmonary shunt is the classical surgical management. Stenting of ductus arteriosus emerged in the last 2 decades as an alternative plausible intervention.ObjectivesTo evaluate and compare the short and midterm effects of PDA stenting in compared to surgically placed shunt for augmentation of pulmonary blood flow looking to pulmonary artery (PA) branches growth, oxygen saturation and suitability for second stage repair.MethodsWe conducted this prospective study in Cardiac Surgical Intensive Care Unit. Cases were divided into “stent group” and “surgical shunt” group. Results were compared between two groups regarding oxygen saturation, mechanical ventilation duration, intensive care stay, mortality and morbidity. Growth of PA branches was assessed during follow up by echocardiograph. Nakata index score was calculated by angiogram before second stage surgery and was compared between both groups.Results43 patients were included. Forty-two cases were offered stent as initial management. 6/42 cases failed stenting (14%) and 3/42 (7%) required late BT shunt after PDA stenting. 10/43 cases ended up receiving BT shunt and were counted as “surgical shunt group”. Stent group (33 cases) needed less mechanical ventilation (2.08 ± 0.65 vs.7.8 ± 4 days with p = 0.014), and less ICU stay compared with surgical shunt group (6.2 ± 1.02 vs. 14 ± 4.5 days, P = 0.009). Both groups achieved similar growth of pulmonary artery branches (p = 0.6 for Z score of left pulmonary artery and P = 0.8 for Z score for right pulmonary artery). Although “stent group” reached second stage surgery with lower O2 saturation 67.6 ± 4.6 vs. 80 ± 4.2 in “surgical shunt” group with P value = 0.0002). Majority of patients in both groups had some PA distortion and needed surgical reconstruction in main pulmonary artery or in its main branches during second stage repair. 3 cases (7.1%) died soon post stenting versus none in surgical shunt group (p = value 0.57).ConclusionsIn neonates with ductus-dependent pulmonary circulation PDA stenting can be introduced as safe first possible option to augment pulmonary blood flow with good outcome and suitable preparation for second stage palliation.