Protocol for venoarterial ExtraCorporeal Membrane Oxygenation to reduce morbidity and mortality following bilateral lung TransPlantation: the ECMOToP randomised controlled trial

INTRODUCTION

Lung transplantation (LTx) aims at improving survival and quality of life for patients with end-stage lung diseases. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is used as intraoperative support for LTx, despite no precise guidelines for its initiation. We aim to evaluate two strategies of VA-ECMO initiation in the perioperative period in patients with obstructive or restrictive lung disease requiring bilateral LTx. In the control 'on-demand' arm, high haemodynamic and respiratory needs will dictate VA-ECMO initiation; in the experimental 'systematic' arm, VA-ECMO will be pre-emptively initiated. We hypothesise a 'systematic' strategy will increase the number of ventilatory-free days at day 28.

METHODS AND ANALYSIS

We designed a multicentre randomised controlled trial in parallel groups. Adult patients with obstructive or restrictive lung disease requiring bilateral LTx, without a formal indication for pre-emptive VA-ECMO before LTx, will be included. Patients with preoperative pulmonary hypertension with haemodynamic collapse, ECMO as a bridge to transplantation, severe hypoxaemia or hypercarbia will be secondarily excluded. In the systematic group, VA-ECMO will be systematically implanted before the first pulmonary artery cross-clamp. In the on-demand group, VA-ECMO will be implanted intraoperatively if haemodynamic or respiratory indices meet preplanned criteria. Non-inclusion, secondary exclusion and VA-ECMO initiation criteria were validated by a Delphi process among investigators. Postoperative weaning of ECMO and mechanical ventilation will be managed according to best practice guidelines. The number of ventilator-free days at 28 days (primary endpoint) will be compared between the two groups in the intention-to-treat population. Secondary endpoints encompass organ failure occurrence, day 28, day 90 and year 1 vital status, and adverse events.

ETHICS AND DISSEMINATION

The sponsor is the Assistance Publique-Hôpitaux de Paris. The ECMOToP protocol version 2.1 was approved by Comité de Protection des Personnes Ile de France VIII. Results will be published in international peer-reviewed medical journals.

TRIAL REGISTRATION NUMBER

NCT05664204.

Effectiveness of Surgeon-Performed Paravertebral Block Analgesia for Minimally Invasive Thoracic Surgery: A Randomized Clinical Trial

Importance

In minimally invasive thoracic surgery, paravertebral block (PVB) using ultrasound (US)-guided technique is an efficient postoperative analgesia. However, it is an operator-dependent process depending on experience and local resources. Because pain-control failure is highly detrimental, surgeons may consider other locoregional analgesic options.

Objective

To demonstrate the noninferiority of PVB performed by surgeons under video-assisted thoracoscopic surgery (VATS), hereafter referred to as PVB-VATS, as the experimental group compared with PVB performed by anesthesiologists using US-guided technique (PVB-US) as the control group.

Design, Setting, and Participants

In this single-center, noninferiority, patient-blinded, randomized clinical trial conducted from September 8, 2020, to December 8, 2021, patients older than 18 years who were undergoing a scheduled minimally invasive thoracic surgery with lung resection including video-assisted or robotic approaches were included. Exclusion criteria included scheduled open surgery, any antalgic World Health Organization level greater than 2 before surgery, or a medical history of homolateral thoracic surgery. Patients were randomly assigned (1:1) to an intervention group after general anesthesia. They received single-injection PVB before the first incision was made in the control group (PVB-US) or after 1 incision was made under thoracoscopic vision in the experimental group (PVB-VATS).

Interventions

PVB-VATS or PVB-US.

Main Outcomes and Measures

The primary end point was mean 48-hour post-PVB opioid consumption considering a noninferiority range of less than 7.5 mg of opioid consumption between groups. Secondary outcomes included time of anesthesia, surgery, and operating room occupancy; 48-hour pain visual analog scale score at rest and while coughing; and 30-day postoperative complications.

Results

A total of 196 patients were randomly assigned to intervention groups: 98 in the PVB-VATS group (mean [SD] age, 64.6 [9.5] years; 53 female [54.1%]) and 98 in the PVB-US group (mean [SD] age, 65.8 [11.5] years; 62 male [63.3%]). The mean (SD) of 48-hour opioid consumption in the PVB-VATS group (33.9 [19.8] mg; 95% CI, 30.0-37.9 mg) was noninferior to that measured in the PVB-US group (28.5 [18.2] mg; 95% CI, 24.8-32.2 mg; difference: -5.4 mg; 95% CI, -∞ to -0.93; noninferiority Welsh test, P ≤ .001). Pain score at rest and while coughing after surgery, overall time, and postoperative complications did not differ between groups.

Conclusions and Relevance

PVB placed by a surgeon during thoracoscopy was noninferior to PVB placed by an anesthesiologist using ultrasonography before incision in terms of opioid consumption during the first 48 hours.

Trial Registration

ClinicalTrials.gov Identifier: NCT04579276.

Peripheral location of lung cancer is associated with higher local disease recurrence

OBJECTIVES

To evaluate the association between the distance of the tumour to the visceral pleura, and the rate of local recurrence in patient surgically treated for stage pI lung cancer.

METHODS

A single centre retrospective review of 578 subsequent patients with a clinical stage IA lung cancer who underwent lobectomy or segmentectomy from January 2010 to December 2019. Were excluded those 107 patients with either positive margins, previous lung cancer, neoadjuvant treatment, pathological stage II or higher status, or patients in whom preoperative CT-scan was not available at the time of the study. Distance between the tumour and the closest visceral pleura area (fissure/mediastinum/lateral) was assessed by two independent investigators, using the preoperative CT-scan and multiplanar 3D reconstructions. An AUC curve was performed to determine the best threshold for tumour/pleura distance, and then multivariable survival analyses to assess the relationship between local recurrence and this threshold adjusting on other variables.

RESULTS

Local recurrence occurred in 27/471 patients (5.8%). A cut-off value of 5 mm between the tumour and the pleura was statistically determined. In multivariable analysis, local recurrence rate was significantly higher in patients with tumour-to-pleura ≤5mm, compared to patients with tumour-to-pleura >5mm (8.5% vs 2.7%, HR 3.36, 95% CI: 1.31-8.59, p = 0.012). Sub-group analyses regarding patients with pIA and tumour size ≤2cm found local recurrence in 4/78 patients treated with segmentectomy (5.1%), with a significant higher occurrence in tumour-to-pleura ≤5mm (11.4% vs 0%, p = 0.037), and in 16/292 patients treated with lobectomy (5.5%) without significant higher occurrence in tumour-to-pleura ≤5mm (7.7% vs 3.4%, p = 0.13).

CONCLUSIONS

Peripheral location of lung tumour is associated with a higher rate of local recurrence and should be taken into account during preoperative planning when considering segmental versus lobar resection.

Epidemiological Study to Assess the Prevalence of Lung Cancer in patients with smoking-associated atherosclerotic cardiovascular diseases: PREVALUNG study protocol

INTRODUCTION

Eligibility criteria definition for a lung cancer screening (LCS) is an unmet need. We hypothesised that patients with a history of atheromatous cardiovascular disease (ACVD) associated with tobacco consumption are at risk of lung cancer (LC). The main objective is to assess LC prevalence among patients with ACVD and history of tobacco consumption by using low-dose chest CT scan. Secondary objectives include the evaluation LCS in this population and the constitution of a biological biobank to stratify risk of LC.

METHODS AND ANALYSIS

We are performing a monocentric 'single-centre' prospective study among patients followed up in adult cardiovascular programmes of vascular surgery, cardiology and cardiac surgery recruited from 18 November 2019 to 18 May 2021. The inclusion criteria are (1) age 45-75 years old, (2) history of ACVD and (3) history of daily tobacco consumption for 10 years prior to onset of ACVD. Exclusion criteria are symptoms of LC, existing follow-up for pulmonary nodule, fibrosis, pulmonary hypertension, resting dyspnoea and active pulmonary infectious disease. We targeted the inclusion of 500 patients. After inclusion (V0), patients are scheduled for a low-dose chest CT and blood and faeces harvesting within 7 months (V1). Each patient is scheduled for a follow-up by telephonic visits at month 3 (V2), month 6 (V3) and month 12 (V4) after V1. Each patient is followed up until 1 year after V1 (14 February 2023). We measure LC prevalence and quantify the National Lung Screening Trial and Dutch-Belgian Randomized Lung Cancer Screening Trial (NELSON) trial eligibility criteria, radiation, positive screening, false positivity, rate of localised LC diagnosis, quality of life with the Short Form 12 (SF-12) and anxiety with the Spielberger State-Trait Anxiety Inventory A and B (STAI-YA and STAI-YB, respectively), smoking cessation and onset of cardiovascular and oncological events within 1 year of follow-up. A case-control study nested in the cohort is performed to identify clinical or biological candidate biomarkers of LC.

ETHICS AND DISSEMINATION

The study was approved according the French Jardé law; the study is referenced at the French 'Agence Nationale de Sécurité du Médicament et des Produits de Santé' (reference ID RCB: 2019-A00262-55) and registered on clinicaltrial.gov. The results of the study will be presented after the closure of the follow-up scheduled on 14 February 2023 and disseminated through peer-reviewed journals and national and international conferences.

TRIAL REGISTRATION NUMBER

NCT03976804.

Benignant and malignant epidemiology among surgical resections for suspicious solitary lung cancer without preoperative tissue diagnosis

OBJECTIVES

The aim of this study was to describe the epidemiology of patients undergoing diagnostic and/or curative surgical pulmonary resections for lung opacities suspected of being localized primary lung cancers without preoperative tissue confirmation.

METHODS

We performed a single-centre retrospective study of a prospectively implemented institutional database of all patients who underwent pulmonary resection between January 2010 and December 2020. Patients were selected when surgery complied with the Fleischner society guidelines. We performed a multivariable logistic regression to determine the preoperative variables associated with malignancy.

RESULTS

Among 1392 patients, 213 (15.3%) had a final diagnosis of benignancy. We quantified futile parenchymal resections in 29 (2.1%) patients defined by an anatomical resection of >2 lung segments for benign lesions that did not modified the clinical management. Compared with patients with malignancies, patients with benignancies were younger (57.5 vs 63.9 years, P < 0.001), had lower preoperative risk profile (thoracoscore 0.4 vs 2.1, P < 0.001), had a higher proportion of wedge resection (50.7% vs 12.2%, P < 0.01) and experienced a lower burden of postoperative complication (Clavien-Dindo IV or V, 0.4% vs 5.6%, P < 0.001). Preoperative independent variables associated with malignancy were (adjusted odd ratio [95% confident interval]) age 1.02 [1.00; 1.04], smoking (year-pack) 1.005 (1.00; 1.01), history of cardiovascular disease 2.06 [1.30; 3.30], history of controlled cancer 2.74 [1.30; 6.88] and clinical N involvement 4.20 [1.11; 37.44].

CONCLUSIONS

Futile parenchymal lung resection for suspicious opacities without preoperative tissue diagnosis is rare (2.1%) while surgery for benign lesions represented 15.3% and has a satisfactory safety profile with very low postoperative morbi-mortality.

Pulsatile pulmonary artery pressure in a large animal model of chronic thromboembolic pulmonary hypertension: Similarities and differences with human data

A striking feature of the human pulmonary circulation is that mean (mPAP) and systolic (sPAP) pulmonary artery pressures (PAPs) are strongly related and, thus, are essentially redundant. According to the empirical formula documented under normotensive and hypertensive conditions (mPAP = 0.61 sPAP + 2 mmHg), sPAP matches ~160%mPAP on average. This attests to the high pulsatility of PAP, as also witnessed by the near equality of PA pulse pressure and mPAP. Our prospective study tested if pressure redundancy and high pulsatility also apply in a piglet model of chronic thromboembolic pulmonary hypertension (CTEPH). At baseline (Week‐0, W0), Sham (n = 8) and CTEPH (n = 27) had similar mPAP and stroke volume. At W6, mPAP increased in CTEPH only, with a two‐ to three‐fold increase in PA stiffness and total pulmonary resistance. Seven CTEPH piglets were also studied at W16 at baseline, after volume loading, and after acute pulmonary embolism associated with dobutamine infusion. There was a strong linear relationship between sPAP and mPAP (1) at W0 and W6 (n = 70 data points, r² = 0.95); (2) in the subgroup studied at W16 (n = 21, r² = 0.97); and (3) when all data were pooled (n = 91, r² = 0.97, sPAP range 9–112 mmHg). The PA pulsatility was lower than that expected based on observations in humans: sPAP matched ~120%mPAP only and PA pulse pressure was markedly lower than mPAP. In conclusion, the redundancy between mPAP and sPAP seems a characteristic of the pulmonary circulation independent of the species. However, it is suggested that the sPAP thresholds used to define PH in animals are species‐ and/or model‐dependent and thus must be validated.

Risk Prediction Model of 90-Day Mortality After Esophagectomy for Cancer

Importance

Ninety-day mortality rates after esophagectomy are an indicator of the quality of surgical oncologic management. Accurate risk prediction based on large data sets may aid patients and surgeons in making informed decisions.

Objective

To develop and validate a risk prediction model of death within 90 days after esophagectomy for cancer using the International Esodata Study Group (IESG) database, the largest existing prospective, multicenter cohort reporting standardized postoperative outcomes.

Design, Setting, and Participants

In this diagnostic/prognostic study, we performed a retrospective analysis of patients from 39 institutions in 19 countries between January 1, 2015, and December 31, 2019. Patients with esophageal cancer were randomly assigned to development and validation cohorts. A scoring system that predicted death within 90 days based on logistic regression β coefficients was conducted. A final prognostic score was determined and categorized into homogeneous risk groups that predicted death within 90 days. Calibration and discrimination tests were assessed between cohorts.

Exposures

Esophageal resection for cancer of the esophagus and gastroesophageal junction.

Main Outcomes and Measures

All-cause postoperative 90-day mortality.

Results

A total of 8403 patients (mean [SD] age, 63.6 [9.0] years; 6641 [79.0%] male) were included. The 30-day mortality rate was 2.0% (n = 164), and the 90-day mortality rate was 4.2% (n = 353). Development (n = 4172) and validation (n = 4231) cohorts were randomly assigned. The multiple logistic regression model identified 10 weighted point variables factored into the prognostic score: age, sex, body mass index, performance status, myocardial infarction, connective tissue disease, peripheral vascular disease, liver disease, neoadjuvant treatment, and hospital volume. The prognostic scores were categorized into 5 risk groups: very low risk (score, ≥1; 90-day mortality, 1.8%), low risk (score, 0; 90-day mortality, 3.0%), medium risk (score, -1 to -2; 90-day mortality, 5.8%), high risk (score, -3 to -4: 90-day mortality, 8.9%), and very high risk (score, ≤-5; 90-day mortality, 18.2%). The model was supported by nonsignificance in the Hosmer-Lemeshow test. The discrimination (area under the receiver operating characteristic curve) was 0.68 (95% CI, 0.64-0.72) in the development cohort and 0.64 (95% CI, 0.60-0.69) in the validation cohort.

Conclusions and Relevance

In this study, on the basis of preoperative variables, the IESG risk prediction model allowed stratification of an individual patient's risk of death within 90 days after esophagectomy. These data suggest that this model can help in the decision-making process when esophageal cancer surgery is being considered and in informed consent.

Superior vena cava prosthetic replacement for non-small cell lung cancer: is it worthwhile?

OBJECTIVES

Direct involvement of the superior vena cava (SVC) by non-small cell lung cancer (NSCLC) requires en-bloc tumour resection with complete vascular clamping and prosthetic replacement. We report the outcomes of this highly demanding procedure in the largest patient cohort to date.

METHODS

We searched our institution's database for patients who underwent complete en-bloc resection of NSCLC invading the SVC followed by prosthetic SVC replacement, between 1980 and 2018. Patients with cN2, cN3 or distant metastases were not eligible.

RESULTS

We identified 48 patients (38 males, 10 females; mean age of 57 years; tumour size, 1.9-17 cm). Neoadjuvant therapy was administered to 17 and adjuvant therapy to 31 patients. R0 resection was achieved in 41 (85%) patients; lymph node involvement was pN0 in 8, pN1 in 23, pN2 in 14 and pN3 in 3 patients. Five patients died within 30 days of surgery. Right pneumonectomy was significantly associated with postoperative death (P = 0.02). Postoperative complications developed in 13 other patients. No neurologic events related to SVC clamping occurred. Graft thrombosis developed in 2 patients. Median survival was 24 months; 3-, 5- and 10-year survival rates were 45%, 40% and 35%, respectively; and corresponding disease-free survival rates were 37%, 37% and 30%, respectively. By univariable analysis, only margin-free (R0) resection was associated with better survival (P = 0.02).

CONCLUSIONS

In highly selected patients with NSCLC involving the SVC, mortality is acceptable after complete en-bloc resection and prosthetic replacement done in an expert centre. SVC involvement should not preclude consideration of curative resection in selected patients.

Video-Assisted Thoracoscopic En Bloc Vertebrectomy for Spine Tumors: Technique and Outcomes in a Series of 33 Patients

BACKGROUND

In en bloc vertebrectomy, the posterior approach is associated with limited access to anterior structures (vertebral body, esophagus, aorta, azygos vein). Video-assisted thoracoscopic surgery (VATS) might prove to be advantageous during thoracic en bloc vertebrectomy by allowing a combined anterior-posterior access in the prone position. We describe the technique and review the outcomes of 33 cases of video-assisted thoracoscopic en bloc vertebrectomy.

METHODS

A retrospective, single-center cohort study included all cases of VATS with a minimum follow-up of 1 year. A team of thoracic and orthopaedic surgeons performed the surgical procedure with the patient in a single, prone position. Anterior release was carried out thoracoscopically, followed by posterior en bloc tumor removal.

RESULTS

From 2003 to 2019, 33 patients were included. Nine patients underwent total vertebrectomy (8 had single-level and 1 had 3-level), and 24 patients underwent partial vertebrectomy (1 had single-level, 8 had 2-level, 13 had 3-level, and 2 had 4-level). Ten patients had pulmonary resection. Histology revealed 18 cases (55%) of primary bone tumors, 6 cases (18%) of lung cancer invading the spine, 6 cases (18%) of solitary metastasis, and 3 other cases (9%). The margins were tumor-free in 28 cases (85%). The median operative time was 240 minutes (range, 150 to 510 minutes), with a median blood loss of 1,200 mL (range, 400 to 6,700 mL), and there were 2 cases of conversion to thoracotomy. A total of 33 complications occurred in 18 patients (55%), and these were predominantly pulmonary. One death was surgery-related (infection). One patient had a persistent monoplegia. At a median follow-up of 63 months (range, 12 to 156 months), there were 21 surviving patients (64%) with 2 local recurrences and 1 distant recurrence, and 2 patients (6%) were lost to follow-up. The survival rates were 94% at 1 year, 71% at 2 years, and 68% at 5 years.

CONCLUSIONS

VATS en bloc vertebrectomy may be indicated for T2-to-T11 spine tumors with the exception of massive tumors, substantial chest wall and/or mediastinal invasion, and lung cancer exceeding 7 cm. The technique yielded satisfactory surgical and oncologic outcomes.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The isobaric pulmonary arterial compliance in pulmonary hypertension

Pulmonary hypertension is associated with stiffening of pulmonary arteries which increases right ventricular pulsatile loading. High pulmonary artery wedge pressure (PAWP) in postcapillary pulmonary hypertension (Pc-PH) further decreases pulmonary arterial compliance (PAC) at a given pulmonary vascular resistance (PVR) compared with precapillary pulmonary hypertension, thus responsible for a higher total arterial load. In all other vascular beds, arterial compliance is considered as mainly determined by the distending pressure, due to non-linear stress-strain behaviour of arteries. We tested the applicability, advantages and drawbacks of two comparison methods of PAC depending on the level of mean pulmonary arterial pressure (mPAP; isobaric PAC) or PVR.

Right heart catheterisation data including PAC (stroke volume/pulse pressure) were obtained in 112 Pc-PH (of whom 61 had combined postcapillary and precapillary pulmonary hypertension) and 719 idiopathic pulmonary arterial hypertension (iPAH).

PAC could be compared over the same mPAP range (25–66 mmHg) in 792 (95.3%) out of 831 patients and over the same PVR range (3–10.7 WU) in only 520 (62.6%) out of 831 patients. The main assumption underlying comparisons at a given PVR was not verified as the PVR×PAC product (RC-time) was not constant but on the contrary more variable than mPAP. In the 788/831 (94.8%) patients studied over the same PAC range (0.62–6.5 mL·mmHg⁻¹), PVR and thus total arterial load tended to be higher in iPAH.

Our study favours comparing PAC at fixed mPAP level (isobaric PAC) rather than at fixed PVR. A reappraisal of the effects of PAWP on the pulsatile and total arterial load put on the right heart is needed, and this point deserves further studies.

In postcapillary and precapillary pulmonary hypertension patients, this study favours comparing pulmonary arterial compliance (PAC) at fixed mean pulmonary artery pressure level (isobaric PAC) rather than at fixed pulmonary vascular resistance levelhttps://bit.ly/3aTLYdS

Extrapleural cervico-manubriotomy and clavicular swing for the management of a mesenchymal tumour of the middle scalenus: an adapted anterior thoracic inlet approach

Surgical approach for resection of tumours involving the thoracic inlet has largely been developed in the context of lung cancer of the superior sulcus. Therefore, initial anterior approaches included a thoracotomy associated with a longitudinal cervicotomy. Here, we describe a variation of the previously described anterior surgical approaches of the thoracic inlet that we performed for the resection of a primary mesenchymal tumour of the left middle scalenus muscle secreting fibroblast growth factor-23 responsible for tumour-induced osteomalacia. This approach allowed a safe control of the great vessels phrenic nerve and brachial plexus as well as a comfortable access to the middle scalenus muscle through an L-shaped incision with a cervico-manubriotomy without thoracotomy. The tumour was resected entirely with the middle scalenus. After 3 months of follow-up, the symptoms resolved entirely.

Lung and heart-lung transplantation for children with PAH: Dramatic benefits from the implementation of a high-priority allocation program in France

PURPOSE

Pulmonary arterial hypertension (PAH) is rare but remains fatal in infants and children despite the advance of targeted therapies. Lung transplantation (LTx), first performed in pediatric patients in the 1980s, is, with the Potts shunt, the only potentially life-extending option in patients with end-stage PAH but is possible only in tightly selected patients. Size-matching challenges severely restrict the donor organ pool, resulting-together with peculiarities of PAH in infants-in high waitlist mortality. We aimed to investigate survival when using a high-priority allocation program (HPAP) in children with PAH listed for double-LTx or heart-LTx.

METHODS

We conducted a single-center, retrospective, before-after study of consecutive children with severe Group 1 PAH listed for double-LTx or heart-LTx between 1988 and 2019. The HPAP was implemented in France in 2006 and 2007 for heart-LTx and double-LTx, respectively.

RESULTS

Fifty-five children with PAH were listed for transplantation. Mean age at transplantation was 15.8±2.8 years and 72% had heart-lung transplantation. PAH was usually idiopathic (65%) or due to congenital heart disease (25%). HPAP implementation resulted in the following significant benefits: Decreased cumulative incidence of waitlist death within 1 and 2 years (p < 0.0001); increased cumulative incidence of transplantation within 6 months, from 44% to 67% (p < 0.01); and improved survival after listing (at 1, 3, and 5 years: 61%, 50%, and 44% vs. 92%, 84%, and 72% before and after HPAP implementation, respectively; p = 0.02).

CONCLUSION

HPAP implementation was associated with significant improvements in access to transplantation and in survival after listing in children with end-stage PAH.

Early-stage non-small cell lung cancer beyond life expectancy: Still not too old for surgery?

OBJECTIVE

We investigated on the benefit/risk ratio of surgery in octogenarians with early-stage non-small cell lung cancer (NSCLC).

MATERIAL AND METHODS

From 2005-2020, 100 octogenarians were operated on for a clinical stage IA to IIA NSCLC. All patients had undergone whole body PET -scan and brain imaging. Operability was assessed according to current guidelines regarding the cardiopulmonary function. Since 2015, patients followed a dedicated geriatric evaluation pathway. Minimally invasive approaches were used in 66 patients, and a thoracotomy in 34.

RESULTS

Clavien-Dindo grade ≥ 4 complications occurred in 15 patients within 90 days, including 7 fatalities. At multivariable analysis, the number of co-morbidities was their single independent prognosticator. Following resection, 24 patients met pathological criteria for adjuvant therapy among whom 3 (12.5 %) received platinum-based chemotherapy. Five-year survival rates were overall (OS) 47 ± 6.3 %, disease-free (DFS) 77.6 ± 5.1 %, and lung cancer-specific (CSS) 74.7 ± 6.3 %. Diabetes mellitus impaired significantly long-term outcomes in these 3 dimensions. OS was improved since the introduction of a dedicated geriatric assessment pathway (72.3 % vs. 6.4 %, P = 0.00002), and when minimally invasive techniques were used (42.3 % vs. 11.3 %; P = 0.02). CSS was improved by the performance of systematic lymphadenectomy (55.3 % vs. 26.9 %; P = 0.04). Multivariable and recursive partitioning analyses showed that a decision tree could be built to predict overall survival on the basis of diabetes mellitus, high co-morbidity index and low ppoDLCO values.

CONCLUSIONS

The introduction of a dedicated geriatric assessment pathway to select octogenarians for lung cancer surgery was associated with OS values that are similar to outcomes in younger patients. The use of minimally invasive surgery and the performance of systematic lymphadenectomy were also associated with improved long-term survival. Octogenarians with multiple co-morbid conditions, diabetes mellitus, or low ppo DLCO values may be more appropriately treated with SBRT.

Hemodynamic trajectories and outcomes in patients with pulmonary arterial hypertension

The relative pulmonary to systemic pressure ratio (mean pulmonary arterial pressure/mean arterial pressure) has been proven to be valuable in cardiac surgery. Little is known on the prognostic value of baseline and trajectory of mean pulmonary arterial pressure/mean arterial pressure in pulmonary arterial hypertension. Patients with confirmed idiopathic, familial, drug and toxins, or connective tissue disease-related pulmonary arterial hypertension and at least one complete right heart catheterization were included and prospectively followed-up for 5.9 ± 4.03 years. Correlates of the primary end point (i.e. death or lung transplant need) during follow-up were determined using Cox regression modeling. Results showed that among the 308 patients included, 187 had at least one follow-up catheterization (median time between catheterizations: 2.16 (1.16–3.19) years). In the total cohort (mean age 47.3 ± 14.9 years, 82.8% of female and 58.1% in New York Heart Association class 3 or 4), mean pulmonary arterial pressure/mean arterial pressure (1.38 (1.07–1.77)) was associated with outcome (p = 0.01). Mean pulmonary arterial pressure/mean arterial pressure was incremental to a basic model (including right atrial pressure, systolic blood pressure, New York Heart Association class 3 or 4, and connective tissue disease) for outcome prediction, while mean pulmonary arterial pressure was not. In the 187 patients with a follow-up catheterization, both delta mean pulmonary arterial pressure and delta mean pulmonary arterial pressure/mean arterial pressure were associated with outcome (1.32 (1.11–1.58) and 1.31 (1.1–1.57) respectively, p < 0.01). Mean pulmonary arterial pressure and mean pulmonary arterial pressure/mean arterial pressure were both incremental to the basic model, while worsening in mean pulmonary arterial pressure or mean pulmonary arterial pressure/mean arterial pressure did not reach significance. In conclusion, mean pulmonary arterial pressure/mean arterial pressure at baseline prognosticates long-term outcome with a significant, albeit modest, incremental value to basic variables.

Description, Staging and Quantification of Pulmonary Artery Angiophagy in a Large Animal Model of Chronic Thromboembolic Pulmonary Hypertension

Angiophagy has been described as a non-fibrinolytic mechanism of pulmonary artery (PA) patency restoration after distal (<50 µm in diameter) pulmonary embolism in mice. We hypothesized that angiophagy could achieve muscularized PA patency restoration after pulmonary embolism in piglets and humans. Angiophagy was defined by pathological assessment as the moving of an embolic specimen from the lumen to the interstitium according to three stages in a pig model of chronic thromboembolic pulmonary hypertension (CTEPH) 6 to 10 weeks after embolization with enbucrilate: the embolic specimen is (I) covered by endothelial cells, (II) covered by endothelial cells and smooth muscle cells, and (III) located in the adventitia. In animals, we observed the three stages of the pulmonary angiophagy of enbucrilate emboli in <300 µm PA. Stages II and III were observed in 300 to 1000 μm PA, and only Stage I was observed in larger-diameter PA (>1000 μm). In lung samples from patients with histories of pulmonary embolisms, we observed PA angiophagy stigma for embolic specimens derived from blood clots and from bone marrow emboli. This study provides an original pathological description and staging of PA angiophagy in a large animal model of CTEPH and in humans after pulmonary embolism.

Carotid webs management in symptomatic patients

BACKGROUND

Atypical fibromuscular dysplasia (AFMD), also known as carotid web, is a rare underdiagnosed shelf-like fibrous tissue arising from the posterior carotid artery bulb that is a cause of cryptogenic stroke of the anterior cerebral vascularization. Despite the recurrence and severity of strokes caused by embolization associated with AFMD, there are no recommendations on the best strategy to manage single and bilateral lesions, which have unsatisfactory outcomes when treated with medical treatment exclusively.

METHODS

From January 2016 to April 2019, 365 patients were operated on for a carotid stenosis in our institution. This cohort included 11 patients (3%), with a median age of 41 years (range, 39-51 years), referred by a stroke unit, treated for a symptomatic (10 strokes and 1 recurrent transient ischemic attack) AFMD lesion. Preoperative workup revealed a contralateral similar lesion in 45% of patients (5/11), which all also underwent surgery during a subsequent hospitalization. The diagnosis was confirmed by histologic examination when open surgery was performed. The 30-day and 1-year outcomes were retrospectively reviewed.

RESULTS

Of the 16 AFMD lesions operated, 13 were treated by open surgery (2 by classic endarterectomy and 11 by internal carotid resection-anastomosis) and 3 by carotid artery stenting, respectively, with a mean delay of 85.5 days and 20.5 days after the latest stroke. There was one complication after stenting (external iliac rupture) that was treated by a covered stent, and no perioperative complications after open surgery. The follow-ups at 30 days and 1 year were uneventful for all patients, without any deaths or stroke recurrences.

CONCLUSIONS

Symptomatic AFMD is a rare cause of cryptogenic stroke. Bilateral lesions are frequent. Early intervention is associated with favorable perioperative and 1-year outcomes. Open surgery is the first-line therapeutic option in this young patient population.

Lung transplantation for idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is characterized by relentlessly progressive lung function impairment that is consistently fatal in the absence of lung transplantation, as no curative pharmacological treatment exists. The pace of progression varies across patients, and acute life-threatening exacerbations occur unpredictably, causing further sharp drops in lung function. Recently introduced antifibrotic agents slow the pace of disease progression and may improve survival but fail to stop the fibrotic process. Moreover, the magnitude and kinetics of the response to these drugs cannot be predicted in the individual patient. These characteristics require that lung transplantation be considered early in the course of the disease. However, given the shortage of donor lungs, lung transplantation must be carefully targeted to those patients most likely to benefit. Current guidelines for lung transplantation listing may need reappraisal in the light of recent treatment advances. Patients with IPF often have multiple comorbidities such as coronary heart disease, frailty, and gastro-oesophageal reflux disease (GERD). Consequently, extensive screening for and effective treatment of concomitant conditions is crucial to appropriate candidate selection and outcome optimisation. A multidisciplinary approach is mandatory. Pulmonologists with expertise in IPF must work closely with lung transplant teams. Careful consideration must be given to preoperative optimisation, surgical technique, and pulmonary rehabilitation to produce the best post-transplantation outcomes.

Non-small cell lung carcinomas with CTNNB1 (beta-catenin) mutations: A clinicopathological study of 26 cases

Beta-catenin, encoded by the CTNNB1 gene, plays an important role in cell proliferation. Mutations of CTNNB1 are oncogenic in several tumor types and are often associated with a nuclear abnormal expression. However, such mutations have only rarely been reported in non-small cell lung carcinomas and their clinical signification is not well described. Our study was conducted on 26 CTNNB1-mutated non-small cell lung carcinomas. Tumors were routinely tested by next generation sequencing for mutations in exon 3 of CTNNB1 gene. Twenty three cases were from a series of 925 tumors (2.48%). The hospital files and pathological data, from surgical samples (n = 16), small biopsies (n = 5) and trans-bronchial fine needle aspirations (n = 5), were reviewed. Immunohistochemistry was performed with an anti-beta-catenin antibody. There were 10 female and 16 male patients aged 52 to 83. Eleven of 25 patients were no-smoking or light smokers. Three cases were diagnosed while under treatment with EGFR tyrosine kinase inhibitor. There were 25 adenocarcinomas and 1 squamous cell carcinoma. Most adenocarcinomas had a papillary component and were TTF1-positive. One case was a well-differentiated fetal adenocarcinoma. Eleven cases (42%) with CTNNB1 mutations showed associated EGFR mutations. The frequency of CTNNB1 mutations was higher among EGFR mutated carcinomas. Immunohistochemistry showed heterogeneous nuclear or cytoplasmic abnormal expression. Our study shows that CTNNB1 mutations mostly occur in TTF1-positive adenocarcinomas with a papillary pattern. These mutations are often associated with EGFR mutations and possibly interfer in the mechanism of resistance to tyrosine kinase inhibitors. Our experience suggests that immuno-histochemistry cannot be used for screening.

Echocardiographic evaluations of right ventriculo-arterial coupling in experimental and clinical pulmonary hypertension

BACKGROUND

Tricuspid annular systolic excursion (TAPSE) or velocities (s') and right ventricular (RV) end-systolic dimensions are predictors of outcome in patients with pulmonary hypertension (PH). We explored the value of combining peak s' and RV end-systolic area index (RVESAi) as a surrogate of RV-pulmonary artery (RV-PA) coupling in a large animal of precapillary PH as well as clinically.

METHOD

The first experimental group included four control and four piglets with thromboembolic disease. RV-PA coupling was assessed by ventricular to arterial elastance ratio (Ees/Ea) at baseline, after esmolol and dobutamine administration. Echocardiographic metrics included s', TAPSE, fractional area change (RVFAC), and RVESAi. The findings were validated in six piglets with severe PH. Clinical cohorts were stable outpatients (n = 141) and acutely decompensated pulmonary arterial hypertension (n = 48).

RESULTS

In the first experimental group, the best linear correlates of Ees/Ea were s' (R2  = .51, p < .001) and RVESAi (R2  = .50, p < .001), while RVFAC (R2  = .17, p = .01) and TAPSE showed weaker association (R2  = .21, p = .39). The ratio s'/RVESAi showed nominally but not significantly (higher) association with Ees/Ea (R2  = .58, p < .01). The association between changes in s'/RVESAi and Ees/Ea was strong (R2  = .56, p < .001). In more severe PH, Ees/Ea and changes in Ees/Ea correlated significantly with s'/RVESAi and changes in s'/RVESAi (R2  = .69; p < .001 and R2  = .64, p < .001, respectively). In the two clinical cohorts, the s'/RVESAi did not emerge as a stronger predictor of outcome than RVESAi.

CONCLUSION

RV s'/RVESAi index represents a reasonable bedside-usable surrogate of RV-PA coupling and of its acute variations in PH. Its incremental prognostic value over end-systolic dimension alone remains to be proven.

P4690Effects of pulmonary artery wedge pressure on right ventricular pulsatile loading in pulmonary hypertension: a reappraisal based on pulmonary arterial isobaric stiffness

Background

Pulmonary hypertension (PH) is associated with stiffening of pulmonary arteries. Previous studies have suggested that high pulmonary artery wedge pressure (PAWP) in postcapillary PH (Pc-PH) further augments PA stiffness at a given level of pulmonary vascular resistance as compared to pulmonary arterial hypertension (PAH). However, these studies do not take into account differences in distending pressure (mean PA pressure, mPAP), which has an effect on stiffness due to non-linear stress-strain behavior of arteries.

Purpose

To compare total PA stiffness between Pc-PH and idiopathic PAH (iPAH) studied at similar mPAP (isobaric stiffness).

Methods

This was an analysis of right heart catheterization results obtained in 112 Pc-PH and 112 iPAH patients extracted from the French PAH network registry and matched for mPAP (median 38 vs 39 mmHg, P=NS), age (70.5 years each) and sex (64% female each). Total PA stiffness was calculated as the ratio of PA pulse pressure to indexed stroke volume.

Results

Total PA stiffness (n=224) increased with mPAP (Spearman's rho = 0.66) and decreased with PAWP (rho = - 0.17) (each P<0.01). The isobaric stiffness was lower in Pc-PH (median (IQR) = 0.91 (0.64–1.39) mmHg/mL/m2) than in iPAH (1.18 (0.83–1.62) mmHg/mL/m2, P<0.01). The patients were then stratified according to their mPAP (25–35 mmHg, n=74 (37/37); 36–43 mmHg, n=75 (34/41); and 44–66 mmHg, n=75 (41/34)). The isobaric stiffness was lower in Pc-PH than iPAH in the 1st mPAP tertile (0.62 vs 0.83 mmHg/mL/m2, P=0.06), in the 2nd mPAP tertile (0.76 vs 1.22 mmHg/mL/m2, P<0.01) and in the 3rd mPAP tertile (1.41 vs 1.77 mmHg/mL/m2, P<0.01). The pulmonary vascular resistance was lower in Pc-PH than iPAH in every mPAP tertile (each P<0.01). Finally, Pc-PH had a higher indexed stroke volume than iPAH (37 (29–48) vs 32 (27–40) mL/m2, P<0.01) while systolic PA pressure and PA pulse pressure were similar.

Conclusion

Unexpectedly, the isobaric pulmonary arterial stiffness was lower in Pc-PH than iPAH patients. It is proposed that PAWP attenuates the increase in RV pulsatile loading in PH when the natural high-strain-induced stiffening was accounted for. This may contribute to a less impaired right ventricular-PA coupling leading to higher indexed stroke volume in Pc-PH than iPAH despite similar PA pressure. At every mPAP level, both the lower PA stiffness and lower pulmonary vascular resistance in Pc-PH than in iPAH may contribute to explain differences in the pressure overload-induced right ventricular adaptation between the two diseased groups, a point that deserves to be confirmed by further studies.

Acknowledgement/Funding

University regular funds

Smooth Muscle Phenotype in Idiopathic Pulmonary Hypertension: Hyper-Proliferative but not Cancerous

Idiopathic pulmonary arterial hypertension (IPAH) is a complex disease associated with vascular remodeling and a proliferative disorder in pulmonary artery smooth muscle cells (PASMCs) that has been variably described as having neoplastic features. To decode the phenotype of PASMCs in IPAH, PASMCs from explanted lungs of patients with IPAH (IPAH-PASMCs) and from controls (C-PASMCs) were cultured. The IPAH-PASMCs grew faster than the controls; however, both growth curves plateaued, suggesting contact inhibition in IPAH cells. No proliferation was seen without stimulation with exogenous growth factors, suggesting that IPAH cells are incapable of self-sufficient growth. IPAH-PASMCs were more resistant to apoptosis than C-PASMCs, consistent with the increase in the Bcl2/Bax ratio. As cell replication is governed by telomere length, these parameters were assessed jointly. Compared to C-PASMCs, IPAH-PASMCs had longer telomeres, but a limited replicative capacity. Additionally, it was noted that IPAH-PASMCs had a shift in energy production from mitochondrial oxidative phosphorylation to aerobic glycolysis. As DNA damage and genomic instability are strongly implicated in IPAH development a comparative genomic hybridization was performed on genomic DNA from PASMCs which showed multiple break-points unaffected by IPAH severity. Activation of DNA damage/repair factors (γH2AX, p53, and GADD45) in response to cisplatin was measured. All proteins showed lower phosphorylation in IPAH samples than in controls, suggesting that the cells were resistant to DNA damage. Despite the cancer-like processes that are associated with end-stage IPAH-PASMCs, we identified no evidence of self-sufficient proliferation in these cells—the defining feature of neoplasia.

Incremental value of right heart metrics and exercise performance to well-validated risk scores in dilated cardiomyopathy

Aims

Risk stratification in heart failure (HF) relies on several established clinical risk scores, however, myocardial deformation, right heart metrics, and exercise performance have not usually been considered. This study sought to assess the incremental value of advanced echocardiographic and cardiopulmonary exercise testing (CPX) parameters to validated risk scores in HF.

Methods and results

The Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) and Metabolic Exercise Test Data Combined with Cardiac and Kidney Indexes (MECKI) scores were applied to 208 ambulatory patients with dilated cardiomyopathy (DCM) who completed echocardiography in conjunction with CPX as part of the Stanford Exercise Testing registry. Patients were followed for the composite end point of death, heart transplant, left ventricular device implantation, and hospitalization for acute HF. Mean age, left ventricular ejection fraction (LVEF), and left ventricular global longitudinal strain (LVGLS) were 47 ± 13 years, 33 ± 13%, and -10.6 ± 4.4%, respectively, while right ventricular free-wall longitudinal strain was -18.8 ± 5.5%. Partial correlation mapping identified strong correlations between LVEF, LVGLS, and LV systolic strain rate, with a moderate correlation between these metrics and peak VO2. Over a median follow up of 5.3 years, the composite end point occurred in 60 patients. Cox proportional hazards identified MAGGIC score [hazard ratio (HR) (2.04 [1.39-3.01], P < 0.01], peak VO2 HR (0.52 [0.28-0.97], P = 0.04), and right atrial volume indexed (RAVI) HR (1.31 [1.07-1.61], P < 0.01) as independent correlates of outcome. RAVI remained an independent correlate when combined with the MECKI score (2.21 [1.59-3.07]), P < 0.01, RAVI, 1.33 [1.06-1.67], P = 0.01).

Conclusion

Our study demonstrates that RAVI is complementary to well-validated HF risk scores and highlights the importance of exercise performance in DCM.

Autologous endothelial progenitor cell therapy improves right ventricular function in a model of chronic thromboembolic pulmonary hypertension

BACKGROUND

Right ventricular (RV) failure is the main prognostic factor in pulmonary hypertension, and ventricular capillary density (CD) has been reported to be a marker of RV maladaptive remodeling and failure. Our aim was to determine whether right intracoronary endothelial progenitor cell (EPC) infusion can improve RV function and CD in a piglet model of chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

We compared 3 groups: sham (n = 5), CTEPH (n = 6), and CTEPH with EPC infusion (CTEPH+EPC; n = 5). After EPC isolation from CTEPH+EPC piglet peripheral blood samples at 3 weeks, the CTEPH and sham groups underwent right intracoronary infusion of saline, and the CTEPH+EPC group received EPCs at 6 weeks. RV function, pulmonary hemodynamics, and myocardial morphometry were investigated in the animals at 10 weeks.

RESULTS

After EPC administration, the RV fractional area change increased from 32.75% (interquartile range [IQR], 29.5%-36.5%) to 39% (IQR, 37.25%-46.50%; P = .030). The CTEPH+EPC piglets had reduced cardiomyocyte surface areas (from 298.3 μm² [IQR, 277.4-335.3 μm²] to 234.6 μm² (IQR, 211.1-264.7 μm²; P = .017), and increased CD31 expression (from 3.12 [IQR, 1.27-5.09] to 7.14 [IQR, 5.56-8.41; P = .017). EPCs were found in the RV free wall at 4 and 24 hours after injection but not 4 weeks later.

CONCLUSIONS

Intracoronary infusion of EPC improved RV function and CD in a piglet model of CTEPH. This novel cell-based therapy might represent a promising RV-targeted treatment in patients with pulmonary hypertension.

Ascending aorta, aortic arch and supra-aortic vessels rupture in blunt thoracic trauma

Surgical strategy and long-term outcomes of patients with rupture of the ascending aorta, aortic arch and supra-aortic vessels following blunt thoracic trauma have been rarely reported. We reviewed our institutional experience between 1995 and 2016. We identified 2 patients with an innominate artery ruptures, 2 with an aortic arch ruptures and 1 with an ascending aorta rupture; all were induced by the posterior displacement of the anterior chest wall. All patients underwent open surgical repair. Cardiopulmonary bypass with antegrade cerebral perfusion was required in 2 cases. All patients were alive at the end of the follow-up (median 18 months; from 3 to 180 months) including 1 patient with cortical blindness.

Impact of the initiation of balloon pulmonary angioplasty program on referral of patients with chronic thromboembolic pulmonary hypertension to surgery

BACKGROUND

Balloon pulmonary angioplasty (BPA) is a technique proposed for inoperable patients with chronic thromboembolic pulmonary hypertension (CTEPH). In this study we aimed to determine whether initiation of the BPA program has modified the characteristics and outcome of patients undergoing pulmonary endarterectomy (PEA), and compared the characteristics of patients undergoing one or the other procedure.

METHODS

This prospective registry study included all patients with CTEPH who underwent PEA in the French National Reference Center before (2012 to 2013) and after (2015 to 2016) BPA program initiation (February 2014). Pre-operative clinical and hemodynamics profiles, peri-operative (Jamieson classification, surgery duration, need of assistance) characteristics of both groups, and all-cause mortality were compared using the t-test or chi-square test. Characteristics of patients subjected to surgery or BPA since February 2014 were also compared.

RESULTS

The total number of patients referred to the CTEPH team increased in the BPA era (n = 291 vs n = 484). The pre-operative characteristics of patients from the pre-BPA era (n = 240) were similar to those from the BPA era (n = 246). Despite more Jamieson Type 3 cases (29%) in the second period, 30- and 90-day mortality remained stable (both p > 0.30). Patients subjected to BPA (n = 177) were older than those subjected to PEA (n = 364) (64 ± 14 vs 60 ± 14 years, respe`ctively), and had higher rates of splenectomy (10% vs 1%) or implantable port (9% vs 3%), lower total pulmonary resistance, better cardiac index, and better renal function (all p < 0.01).

CONCLUSIONS

This study shows the influence of the initiation of the BPA program on the profile of patients with CTEPH undergoing PEA.

Load Adaptability in Patients With Pulmonary Arterial Hypertension

Right ventricular (RV) adaptation to pressure overload is a major prognostic factor in patients with pulmonary arterial hypertension (PAH). The objectives were first to define the relation between RV adaptation and load using allometric modeling, then to compare the prognostic value of different indices of load adaptability in PAH. Both a derivation (n = 85) and a validation cohort (n = 200) were included. Load adaptability was assessed using 3 approaches: (1) surrogates of ventriculo-arterial coupling (e.g., RV area change/end-systolic area), (2) simple ratio of function and load (e.g., tricuspid annular plane systolic excursion/right ventricular systolic pressure), and (3) indices assessing the proportionality of adaptation using allometric pressure-function or size modeling. Proportional hazard modeling was used to compare the hazard ratio for the outcome of death or lung transplantation. The mean age of the derivation cohort was 44 ± 11 years, with 80% female and 74% in New York Heart Association class III or IV. Mean pulmonary vascular resistance index (PVRI) was 24 ± 11 with a wide distribution (1.6 to 57.5 WU/m²). Allometric relations were observed between PVRI and RV fractional area change (R² = 0.53, p < 0.001) and RV end-systolic area indexed to body surface area right ventricular end-systolic area index (RVESAI) (R² = 0.29, p < 0.001), allowing the derivation of simple ratiometric load-specific indices of RV adaptation. In right heart parameters, RVESAI was the strongest predictor of outcomes (hazard ratio per SD = 1.93, 95% confidence interval 1.37 to 2.75, p < 0.001). Although RVESAI/PVRI^0.35 provided small incremental discrimination on multivariate modeling, none of the load-adaptability indices provided stronger discrimination of outcome than simple RV adaptation metrics in either the derivation or the validation cohort. In conclusion, allometric modeling enables quantification of the proportionality of RV load adaptation but offers small incremental prognostic value to RV end-systolic dimension in PAH.

Investigating the value of right heart echocardiographic metrics for detection of pulmonary hypertension in patients with advanced lung disease

This study determined whether novel right heart echocardiography metrics help to detect pulmonary hypertension (PH) in patients with advanced lung disease (ALD). We reviewed echocardiography and catheterization data of 192 patients from the Stanford ALD registry and echocardiograms of 50 healthy controls. Accuracy of echocardiographic right heart metrics to detect PH was assessed using logistic regression and area under the ROC curves (AUC) analysis. Patients were divided into a derivation (n = 92) and validation cohort (n = 100). Experimental validation was assessed in a piglet model of mild PH followed longitudinally. Tricuspid regurgitation (TR) was not interpretable in 52% of patients. In the derivation cohort, right atrial maximal volume index (RAVI), ventricular end-systolic area index (RVESAI), free-wall longitudinal strain and tricuspid annular plane systolic excursion (TAPSE) differentiated patients with and without PH; 20% of patients without PH had moderate to severe RV enlargement by RVESAI. On multivariate analysis, RAVI and TAPSE were independently associated with PH (AUC = 0.77, p < 0.001), which was confirmed in the validation cohort (0.78, p < 0.001). Presence of right heart metrics abnormalities did not improve detection of PH in patients with interpretable TR (p > 0.05) and provided moderate detection value in patients without TR. Only two patients with more severe PH (mean pulmonary pressure 35 and 36 mmHg) were missed. The animal model confirmed that right heart enlargement discriminated best pigs with PH from shams. This study highlights the frequency of right heart enlargement and dysfunction in ALD irrespectively from presence of PH, therefore limiting their use for detection of PH.

Right ventricular reserve in a piglet model of chronic pulmonary hypertension

Right ventricular (RV) response to exercise or pharmacological stress is not well documented in pulmonary hypertension (PH). We investigated the relationship between RV reserve and ventricular-arterial coupling. Surgical ligation of the left pulmonary artery was performed in 13 Large White piglets (PH group), thereafter weekly embolisations of the right lower lobe were performed for 5 weeks. A control group of six piglets underwent sham procedures. Right heart catheterisation and echocardiography were performed at week 6. Pressure-volume loops were recorded before and after dobutamine infusion. Induction of experimental PH resulted in a higher mean ± sd pulmonary artery pressure (34 ± 9 versus 14 ± 2 mmHg; p<0.01) and in a lower ventricular-arterial coupling efficiency (0.66 ± 0.18 versus 1.24 ± 0.17; p<0.01) compared with controls at 6 weeks. Dobutamine-induced relative changes in RV stroke volume index (SVI) and end-systolic elastance were lower in the PH group (mean ± SD 47 ± 5% versus 20 ± 5%, p<0.01, and 81 ± 37% versus 32 ± 14%, p<0.01, respectively). Change in SVI was strongly associated with resting ventricular-arterial coupling (R(2)=0.74; p<0.01). RV reserve was associated with ventricular-arterial coupling in a porcine model of chronic pressure overload.

Microvascular disease in chronic thromboembolic pulmonary hypertension: a role for pulmonary veins and systemic vasculature

Limited numbers of operated patients with chronic thromboembolic pulmonary hypertension (CTEPH) are refractory to pulmonary endarterectomy (PEA) and experience persistent pulmonary hypertension (PH).

We retrospectively assessed lung histology available from nine patients with persistent PH (ineffective PEA (inPEA) group) and from eight patients transplanted for distal CTEPH inaccessible by PEA (noPEA group). Microscopically observed peculiarities were compared with the histology of a recently developed CTEPH model in piglets. Pre-interventional clinical/haemodynamic data and medical history of patients from the inPEA and noPEA groups were collected and analysed.

Conspicuous remodelling of small pulmonary arteries/arterioles, septal veins and pre-septal venules, including focal capillary haemangiomatosis, as well as pronounced hypertrophy and enlargement of bronchial systemic vessels, were the predominant pattern in histology from both groups. Most findings were reproduced in our porcine CTEPH model. Ink injection experiments unmasked abundant venular involvement in so-called small vessel or microvascular disease, as well as post-capillary bronchopulmonary shunting in human and experimental CTEPH.

Microvascular disease is partly due to post-capillary remodelling in human and experimental CTEPH and appears to be related to bronchial-to-pulmonary venous shunting. Further studies are needed to clinically assess the functional importance of this finding.