Atrial Arrhythmias Following Pulmonary Thromboendarterectomy: A Comprehensive Review Of Current Literature.

Chronic thromboembolic pulmonary hypertension (CTEPH) presents as a progressive vascular condition arising from previous episodes of acute pulmonary embolism, contributing to the development of pulmonary hypertension (PH). Pulmonary thromboendarterectomy (PTE) is the gold-standard surgical treatment for CTEPH; however, it may be associated with postoperative sequelae, including atrial arrhythmias (AAs). This comprehensive literature review explores the potential mechanisms for PTE-induced AAs with emphasis on the role of PH-related atrial remodelling and the predisposing factors. The identified preoperative predictors for AAs include advanced age, male gender, elevated resting heart rate, previous AAs, and baseline elevated right atrial pressure. Furthermore, we explore the available data on the association between post-PTE pericardial effusions and the development of AAs. Lastly, we briefly discuss the emerging role of radiomic analysis of epicardial adipose tissue as an imaging biomarker for predicting AAs.

The Initial Experience of Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension in Latvia.

Background: Treatment options for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) or persistent pulmonary hypertension after pulmonary endarterectomy (PEA) include targeted medical therapy and balloon pulmonary angioplasty (BPA). BPA is an emerging treatment modality that has been reported to improve functional capacity, pulmonary hemodynamics, and right ventricular function. Reports from expert centers are promising, but more data are needed to make the results more generalizable. Materials and Methods: We conducted a prospective analysis of nine consecutive CTEPH patients who underwent balloon pulmonary angioplasty (BPA) sessions at Pauls Stradins Clinical University Hospital in Riga, Latvia between 1 April 2022 and 1 July 2023. We assessed World Health Organization (WHO) functional class, 6 min walk distance (6MWD), blood oxygen saturation (SpO2), brain natriuretic peptide (BNP) level at baseline and 3 months after the first BPA session. For two patients on whom repeated BPA sessions were performed, we additionally assessed cardiac output (CO), pulmonary vascular resistance (PVR), and mean pulmonary artery pressure (mPAP). Results: A total of 12 BPA procedures for nine patients were performed; repeated BPA sessions were performed for two patients. Our results show a reduction in BNP levels and improvement in WHO functional class, 6MWD, and SpO2 after the first BPA session. Improvement in 6MWD was statistically significant. Additionally, an improvement in pulmonary hemodynamic parameters was observed. Conclusions: Our data show that BPA is an effective interventional treatment modality, improving both the pulmonary hemodynamics and functional status. Moreover, BPA is safe and excellently tolerated.

Effect of epoprostenol-induced thrombocytopaenia on lung transplantation for pulmonary arterial hypertension.

OBJECTIVES: Preoperative intravenous epoprostenol therapy can cause thrombocytopaenia, which may increase the risk of perioperative bleeding during lung transplantation. This study aimed to determine whether lung transplantation can be safely performed in patients with epoprostenol-induced thrombocytopaenia. METHODS: From June 2008 to July 2022, we performed 37 lung transplants in patients with pulmonary arterial hypertension (PAH), including idiopathic PAH (n = 26), congenital heart disease-associated PAH (n = 7), pulmonary veno-occlusive disease (n = 3) and peripheral pulmonary artery stenosis (n = 1) at our institution. Of these, 26 patients received intravenous epoprostenol therapy (EPO group), whereas 11 patients were treated with no epoprostenol (no-EPO group). We retrospectively analysed the preoperative and postoperative platelet counts and post-transplant outcomes in each group. RESULTS: Preoperative platelet counts were relatively lower in the EPO group than in the no-EPO group (median EPO: 127 000 vs no-EPO: 176 000/µl). However, blood loss during surgery was similar between the 2 groups (EPO: 2473 ml vs no-EPO: 2615 ml). The platelet counts significantly increased over 1 month after surgery, and both groups showed similar platelet counts (EPO: 298 000 vs no-EPO: 284 000/µl). In-hospital mortality (EPO: 3.9% vs no-EPO: 18.2%) and the 3-year survival rate (EPO: 91.4% vs no-EPO: 80.8%) were similar between the 2 groups. CONCLUSIONS: Patients with PAH treated with intravenous epoprostenol showed relatively lower platelet counts, which improved after lung transplantation with good post-transplant outcomes.

[Pulmonary artery stenting in chronic thromboembolic pulmonary hypertension: a report of 2 cases].

Chronic thromboembolic pulmonary hypertension (CTEPH) is a pulmonary vascular disease characterized by an insidious onset, progressive deterioration, and poor prognosis. It is distinguished by the thrombotic organization within the pulmonary arteries, leading to vascular stenosis or occlusion. This results in a progressive increase in pulmonary vascular resistance and pulmonary arterial pressure, ultimately leading to right heart failure. In recent years, balloon pulmonary angioplasty (BPA) has emerged as an effective treatment option for patients ineligible for pulmonary endarterectomy (PEA). However, the use of stents in patients with suboptimal balloon dilation remains controversial. This article describes two cases of chronic thromboembolic pulmonary hypertension (CTEPH) in which balloon angioplasty yielded unsatisfactory results, subsequently leading to stent placement. Following stent implantation, there was improved blood flow, significant reduction in pulmonary arterial pressure, and notable alleviation of patient symptoms. One-year follow-up showed no recurrence of stenosis within the stent, suggesting potential guidance for the use of pulmonary artery stenting as a treatment modality for CTEPH. This report provided new insights into the therapeutic approach for CTEPH.

Improvement in Pulmonary Hypertension Following Metabolic and Bariatric Surgery: a Brief Review and Meta-analysis.

We reviewed the available evidence on the outcome of metabolic and bariatric surgery (MBS) in patients with pulmonary hypertension (PH). Five studies examining 174 patients were included; the mean age was 54.5 ± 9.27 years; the mean BMI before surgery and at the end of follow-up were 47.2 ± 5.95 kg/m2 and 37.4 ± 2.51 kg/m2, respectively. Furthermore, the results showed a significant decrease in the right ventricle systolic pressure (RVSP) after MBS with a mean difference of 10.11% (CI 95%: 3.52, 16.70, I2 = 85.37%, p = < 0.001), at 16.5  ±  3.8 month follow-up with a morbidity rate of 26% and 0 mortality. Thirty-day postoperative complications included respiratory failure, pulmonary embolism, pulmonary edema, and anastomotic leak. There appears to be a significant improvement in PH with a decrease in medication requirements after MBS.

Chronic Thromboembolic Pulmonary Hypertension.

This JAMA Insights discusses the symptoms, diagnosis, and treatment of chronic thromboembolic pulmonary hypertension.

Does pulmonary endarterectomy improve the clinical conditions of patients with chronic thromboembolic pulmonary disease without pulmonary hypertension?

To verify whether the new hemodynamic definition of pulmonary hypertension (PH) has any implication in treatment of Chronic Thrombo-Embolic Pulmonary Disease (CTEPD) patients without PH, we retrospectively analysed the clinical and functional changes determined by pulmonary endarterectomy (PEA) in 63 CTEPD patients without PH who underwent surgery at our center, comparing those in whom the hemodynamic diagnosis of PH met recent guideline recommendations versus those in whom the diagnosis only met previous hemodynamic thresholds. The results show that the vast majority of CTEPD patients without PH operated at our center would now be defined as chronic thromboembolic pulmonary hypertension (CTEPH) patients. PEA did not result in any improvement in exercise capacity nor in right ventricular function or lung function test in patients with mean pulmonary artery pressure (mPAP) ≤ 20 mm Hg and pulmonary vascular resistance (PVR) ≤ 2 WU; on the contrary, hemodynamic parameters, exercise capacity, right ventricular function and lung function significantly improved in patients with mPAP between 21 and 24 mm Hg.

The long-term outcome of chronic thromboembolic pulmonary hypertension: Pulmonary endarterectomy and balloon pulmonary angioplasty.

BACKGROUND: The long-term outcome on patients with chronic thromboembolic pulmonary hypertension (CTEPH) has not been ideal after standard medical treatment. However, good outcome for patients with CTEPH after interventions such as pulmonary endarterectomy (PEA) and balloon pulmonary angioplasty (BPA) has been reported recently. The aim of this study was to evaluate the impact of PEA or BPA on long-term outcomes for CTEPH patients in Han-Chinese population. METHODS: This was a multicenter, prospective case-control study. Patients with CTEPH were enrolled between January, 2018 and March, 2020. They were divided into two groups, including intervention (PEA or BPA) and conservative groups. The followed-up period was 26 months after treatment. The endpoints were all-cause mortality and CTEPH mortality. RESULTS: A total of 129 patients were enrolled and assigned to receive PEA/BPA (N = 73), or conservative therapy (N = 56). Overall, the 26-month survival rate of all-cause mortality was significantly higher in intervention group compared to that in conservative group (95.89% vs 80.36%; log-rank p = 0.0164). The similar trend was observed in the 26-month survival rate of CTEPH mortality (97.26% vs 85.71%; log-rank p = 0.0355). Regarding Cox proportional-hazard regression analysis, the hazard ratios (HRs) on patients with CTEPH receiving intervention in the outcome of all-cause mortality and CTEPH mortality were statistically significant (HR = 0.07 and p = 0.0141 in all-cause mortality; HR = 0.11 and p = 0.0461 in CTEPH mortality). CONCLUSION: This multicenter prospective case-control study demonstrated that intervention such as PEA and BPA increased the long-term survival rate for patient with CTEPH significantly. Intervention was an independent factor in long-term outcome for patients with CTEPH, including all-cause mortality and CTEPH mortality.

Acute severe pulmonary hypertension during weaning from cardiopulmonary bypass for aortic valve replacement surgery: A case report.

Pulmonary arterial pressure (PAH) usually increases after cardiopulmonary bypass (CPB), but this normally does not affect weaning off CPB. Here we report a case of severe PAH in a patient with normal left atrial pressure. Prolonging CPB by 45 min did not lead to lower PAH. Given that lung injury can stimulate secretion of vasoconstrictors that trigger PAH, we decided to gradually increase blood flow into the lungs in an effort to restore the balance between pulmonary vasoconstrictors and vasodilators. Pulmonary artery pressure gradually decreased, allowing the patient to be weaned off CPB, after which she recovered uneventfully. Our experience suggests an approach for managing acute, severe PAH after CPB without the need for mechanical circulatory support.

Pulmonary thromboendarterectomy in hospitalized versus elective patients with chronic thromboembolic pulmonary hypertension.

OBJECTIVE: We sought to characterize outcomes in patients undergoing pulmonary thromboendarterectomy electively versus after acute presentation. METHODS: This is a retrospective analysis of patients who underwent pulmonary thromboendarterectomy from October 2015 to April 2022. Patients were divided into 2 groups depending on elective surgery or surgery during the same hospitalization as their presentation. RESULTS: In total, 69 patients were included: 45 in the hospitalized group and 24 in the elective group. Patients in the hospitalized group were less likely to have chronic lung disease, history of pulmonary embolism and hypertension, be on anticoagulation and medication for pulmonary hypertension, and present with >1 month of respiratory symptoms. They were more likely to have worse preoperative right ventricular function. Among other demographics, risk factors for venous thromboembolism were similar between both groups. Thirteen patients in the hospitalized group required preoperative extracorporeal membrane oxygenation. There was no difference in disease classification and operative, cardiopulmonary bypass, and hypothermic circulatory arrest durations between both groups. Postoperative complications were similar between both groups, except for greater frequency of deep vein thrombosis in the hospitalized group (26.7% vs 4.2%, P = .03). In-hospital and intensive care unit length of stay were similar between both groups. Overall, in-hospital mortality was 4.3% and was similar between both groups; P = .28. CONCLUSIONS: Our series shows that pulmonary thromboendarterectomy can be safely performed in patients presenting acutely, with comparable postoperative complications and in-hospital mortality to an elective setting. Such patients present with worse right ventricular function, sometimes requiring temporary mechanical support.

Lung transplantation in primary pulmonary arterial hypertension and pulmonary venous hypertension.

OBJECTIVES: End-stage lung disease from primary pulmonary hypertension (PPHTN) and pulmonary venous-occlusive disease (PVOD) may require lung transplantation (LT). While medical therapies exist for the palliation of PPHTN, no therapies exist for PVOD. The study's objective is to compare outcomes of LT in these patients. METHODS: Patients with PPHTN and PVOD who had undergone LT were identified in the UNOS database (2005-2022). Univariable analyses compared differences between groups in demographic, clinical, and post-transplant outcomes. Multivariable logistic regression examined the association between the diagnosis group and survival. Overall survival time between groups was compared using the Kaplan-Meier method. RESULTS: Six hundred and ninety-six PPHTN and 78 PVOD patients underwent LT during the study period. Patients with PVOD had lower pulmonary artery mean pressure (47 vs. 53 mmHg, p < .001), but higher cardiac output (4.51 vs. 4.31 L/min, p = .04). PVOD patients were more likely to receive lungs from donation after cardiac death donors (7.7 vs. 2.9%, p = .04). There were no differences in postoperative complications or length of stay. PVOD was associated with superior survival at 30-day (100 vs. 93%, p = .02) and 90-day post-transplant (93 vs. 83%, p = .03), but not at later time points. In multivariable analyses, PVOD and brain death donor use were associated with better survival up to 90-day mark. CONCLUSIONS: Patients undergoing LT for PVOD had better initial survival, which disappeared after 1 year of transplantation. Donation after circulatory death donor use had a short-term survival disadvantage.

Perioperative extracorporeal membrane oxygenation support for pulmonary endarterectomy: A 17-year experience from the UK national cohort.

BACKGROUND: Pulmonary endarterectomy (PEA) is the guideline-recommended treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, some patients develop severe cardiopulmonary compromise before surgery, intraoperatively, or early postoperatively. This may result from advanced CTEPH, reperfusion pulmonary edema, massive endobronchial bleeding, or right ventricular (RV) failure secondary to residual pulmonary hypertension. Conventional cardiorespiratory support is ineffective when these complications are severe. Since 2005, we used extracorporeal membrane oxygenation (ECMO) as a rescue therapy for this group. We review our experience with ECMO support in these patients. METHODS: This study was a retrospective analysis of patients who received perioperative ECMO for PEA from a single national center from August 2005 to July 2022. Data were prospectively collected. RESULTS: One hundred and ten patients (4.7%) had extreme cardiorespiratory compromise requiring perioperative ECMO. Nine were established on ECMO before PEA. Of those who received ECMO postoperatively, 39 were for refractory reperfusion lung injury, 20 for RV failure, 31 for endobronchial bleeding, and the remaining 11 were for "other" reasons, such as cardiopulmonary resuscitation following late tamponade and aspiration pneumonitis. Sixty-two (56.4%) were successfully weaned from ECMO. Fifty-seven patients left the hospital alive, giving a salvage rate of 51.8%. Distal disease (Jamieson Type III) and significant residual pulmonary hypertension were also predictors of mortality on ECMO support. Overall, 5- and 10-year survival in patients who were discharged alive following ECMO support was 73.9% (SE: 6.1%) and 58.2% (SE: 9.5%), respectively. CONCLUSIONS: Perioperative ECMO support has an appropriate role as rescue therapy for this group. Over 50% survived to hospital discharge. These patients had satisfactory longer-term survival.

Surgery for fibrosing mediastinitis with severe pulmonary hypertension due to pulmonary venous stenosis.

A 21-year-old woman with severe pulmonary hypertension and circulatory collapse was referred to our hospital for possible lung transplantation with extracorporeal membrane oxygenation support. Computed tomography revealed severe stenosis of all 4 pulmonary veins, and fibrosing mediastinitis was suspected. Surgical reconstruction of the pulmonary veins was performed, and extracorporeal membrane oxygenation support was weaned off. After surgery, pulmonary vascular resistance normalized. This successful case demonstrates that surgical pulmonary venous reconstruction is an important treatment for fibrosing mediastinitis induced by pulmonary venous stenosis and pulmonary hypertension.

How Would I Treat My Own Chronic Thromboembolic Pulmonary Hypertension in the Perioperative Period?

Chronic thromboembolic pulmonary hypertension (CTEPH) results from an incomplete resolution of acute pulmonary embolism, leading to occlusive organized thrombi, vascular remodeling, and associated microvasculopathy with pulmonary hypertension (PH). A definitive CTEPH diagnosis requires PH confirmation by right-heart catheterization and evidence of chronic thromboembolic pulmonary disease on imaging studies. Surgical removal of the organized fibrotic material by pulmonary endarterectomy (PEA) under deep hypothermic circulatory arrest represents the treatment of choice. One-third of patients with CTEPH are not deemed suitable for surgical treatment, and medical therapy or interventional balloon pulmonary angioplasty presents alternative treatment options. Pulmonary endarterectomy in patients with technically operable disease significantly improves symptoms, functional capacity, hemodynamics, and quality of life. Perioperative mortality is <2.5% in expert centers where a CTEPH multidisciplinary team optimizes patient selection and ensures the best preoperative optimization according to individualized risk assessment. Despite adequate pulmonary artery clearance, patients might be prone to perioperative complications, such as right ventricular maladaptation, airway bleeding, or pulmonary reperfusion injury. These complications can be treated conventionally, but extracorporeal membrane oxygenation has been included in their management recently. Patients with residual PH post-PEA should be considered for medical or percutaneous interventional therapy.

Predicting Patient Status in Chronic Thromboembolic Pulmonary Hypertension Using a Biophysical Model.

Chronic thromboembolic pulmonary hypertension (CTEPH) involves abnormally high blood pressure in the pulmonary vessels and is associated with small vessel vasculopathy and pre-capillary proximal occlusions. Management of CTEPH disease is challenging, therefore accurate diagnosis is crucial in ensuring effective treatment and improved patient outcomes. The treatment of choice for CTEPH is pulmonary endarterectomy, which is an invasive surgical intervention to remove thrombi. Following PEA, a number of patients experience poor outcomes or worse-than-expected improvements, which may indicate that they have significant small vessel disease. A method that can predict the extent of distal remodelling may provide useful clinical information to plan appropriate CTEPH patient treatment. Here, a novel biophysical modelling approach has been developed to estimate and quantify the extent of distal remodelling. This method includes a combination of mathematical modelling and computed tomography pulmonary angiography to first model the geometry of the pulmonary arteries and to identify the under-perfused regions in CTEPH. The geometric model is then used alongside haemodynamic measurements from right heart catheterisation to predict distal remodelling. In this study, the method is tested and validated using synthetically generated remodelling data. Then, a preliminary application of this technique to patient data is shown to demonstrate the potential of the approach for use in the clinical setting.Clinical relevance- Patient-specific modelling can help provide useful information regarding the extent of distal vasculopathy on a per-patient basis, which remains challenging. Physicians can be unsure of outcomes following pulmonary endarterectomy. Therefore, the predictive aspect of the patient's response to surgery can help with clinical decision-making.