P999Major adverse events with percutaneous left atrial appendage closure in patients with atrial fibrillation in real life setting

Methods

We analysed data from all AF patients treated with Watchman or Amplatzer LAA closure according to European guidelines in 8 French cardiology departments. Antithrombotic management was decided for each patient on an individual basis. A Cox regression model was used for multivariable analysis of major adverse events. Yearly rate of ischemic stroke during follow-up was calculated and compared to that expected for a same risk score population. Yearly rate of bleeding was extrapolated from that reported with the HASBLED score.

Results

A total of 469 consecutive AF patients (299 males, 74.9±8.9 years old, mean CHA2DS2-VASc score 4.5±1.4, HASBLED score 3.7±1.0) received LAA closure from March 2012 to January 2017. There were 272 Watchman devices (58%) and 197 ACP devices (42%) implanted. At discharge, 36% received a single anti platelet therapy (APT), 23% received dual APT, 29% received OAC and no APT, 5% received OAC plus APT and 8% received no antithrombotic therapy. Mean follow up was 11.4 months (median 7, interquartile 3–22 months) during which 70 major adverse events (19 ischemic strokes, 18 major haemorrhages and 33 deaths) were recorded in 69 patients. The annual rate of ischemic stroke was 3.96%, which translates into a 13% relative risk reduction (95% CI −59 to 52%) as compared with the calculated stroke rate for similar CHA2DS2-VASc score after adjustment for exposure to APT and OAC. The annual rate of major bleeding in the study was 3.75%, which corresponds to a 48% relative risk reduction (95% CI 9 to 70%) as compared with the rate that would have been expected based on a comparable HAS-BLED score. Yearly rate of mortality was 7.4% (2.5 to 3 fold higher than in previous randomized trials) and the rate of non-cardiovascular death was 82%. None of the baseline characteristics was predictive of major adverse events, neither in univariate nor in multivariable analysis, which highlights the difficulty in identifying a risk of unfavourable outcome with simple tools.

Conclusions

AF patients treated with LAA closure may have a lower risk of stroke and bleeding events compared to their theoretical risk. However, our findings indicate that a high rate of major adverse events is observed in these patients during follow-up. This questions the suggested cost-effectiveness of the procedure (with models based on previous trials) for a real-life perspective. A better identification of patients with a relevant benefit of LAA closure is needed among those with long-term anticoagulation contraindication, both for an optimal management of each patient on an individual basis and for a global perspective with limited healthcare resources.

P6564Prediction of the progression from paroxysmal to persistent or permanent atrial fibrillation using different scores. Is AF progression mainly atrial aging?

Methods

All patients with AF seen over a period of 10 years were identified in a database and followed up for AF progression and mortality. Predictors of outcomes were identified using Cox regression model. The values of HATCH, CHA2DS2-VASc, ALARMEc, APPLE, MB-LATER scores and CHARLSON comorbidity index were evaluated with C statistics for prediction of AF progression.

Results

Among 8962 patients (71±14 years), 4991, 476 and 3495 had paroxysmal, persistent AF, and permanent AF, respectively. During a follow-up of 927±1084 days, 404 paroxysmal AF patients progressed to persistent or permanent AF (yearly rate of 3.0%). Progression was associated with a trend toward increased cardiovascular mortality. Independent predictors of AF progression were heart failure (hazard ratio (HR) 2.07; 95% CI 1.50–2.85, p<0.0001), valvular disease (HR=1.87, 95% CI=1.35–2.58, p=0.0002) and the use of digoxin (HR=2.39, 95% CI=1.75–3.29, p<0.001). Conversely, a history of stroke was associated with a lower rate of progression (HR=0.50, 95% CI=0.28–0.88, p=0.02). Overall, most of the score, particularly the HATCH score, were modest predictors of progression (table). The best score was actually the CHARLSON comorbidity index. The predictive values of all scores were better on patients not treated with antiarrhythmic agent.

C-statistics for AF progression All patients (n=4,991) p value* HATCH 0.576 (0.562–0.590) <0.0001 CHA2DS2-VASc 0.532 (0.503–0.560) <0.0001 ALARMEc 0.634 (0.607–0.660) 0.03 APPLE 0.631 (0.605–0.658) 0.03 MB-LATER 0.612 (0.587–0.638) 0.001 CHARLSON 0.667 (0.640–0.693) – *DeLong test vs CHARLSON comorbidity index.

Conclusion

Most of scores have a modest predictive value to identify the risk of evolution to permanent AF. Among them, the CHARLSON comorbidity index had the best predictive value and outperformed other tools. This suggests that AF progression may actually reflect global aging both at the individual and local atrial level.

P1870Predicting mortality and mode of death by clinical score systems for patients with atrial fibrillation

Methods

All patients with AF seen in an academic institution were identified and followed up for mortality. CHA2DS2VASc score, CCI and CFI were calculated for each patient. Predictive abilities of the scores were compared using the c-statistic.

Results

Among 8962 consecutive patients with AF, 1294 patients died during a follow-up of 929±1082 days (median 456), (yearly rate 5.5%) and 97% of causes of death were identified (54% cardiovascular and 43% non-cardiovascular). Death occurred more often in patients with higher CHA2DS2VASc scores, CCI and CFI. CFI was a better predictor of total mortality than CCI and CHA2DS2VASc score (table). CFI was also a better predictor of cardiovascular mortality than CCI and CHA2DS2VASc score. Finally, CFI was also a better predictor of non-cardiovascular mortality than CCI and CHA2DS2VASc score. The predictive performances of the 3 tools were better for cardiovascular death than for non-cardiovascular death.

Prediction of mode of death ROC area (95% C) p vs CHA2DS2VASc/Charlson Total mortality CHA2DS2VASc 0.651 (0.636–0.665) – / 0.0001 CHARLSON (CCI) 0.687 (0.672–0.702) 0.0001 / – Frailty index (CFI) 0.714 (0.700–0.729) <0.0001 / <0.0001 Cardiovascular death CHA2DS2VASc 0.673 (0.654–0.692) – / 0.004 CHARLSON (CCI) 0.707 (0.688–0.726) 0.004 / – Frailty index (CFI) 0.737 (0.719–0.756) <0.0001 / <0.0001 Non cardiovascular death CHA2DS2VASc 0.590 (0.567–0.612) – / 0.0008 CHARLSON (CCI) 0.637 (0.614–0.659) 0.0008 / – Frailty index (CFI) 0.650 (0.628–0.672) <0.0001 / 0.008

Conclusion

Frailty assessed with CFI demonstrated better performances in predicting total mortality, cardiovascular mortality and non-cardiovascular mortality than CHA2DS2VASc score and Charlson comorbidity index in AF patients. Identifying the risk of non-cardiovascular death with simple tools remains a more difficult challenge in these patients.

P5675Ischemic stroke in patient with sinus node disease in comparison to atrial fibrillation, bradycardia-tachycardia syndrome and other cardiac conditions: a nationwide cohort-study

Methods

This French longitudinal cohort study was based on the national database covering hospital care from for the entire population (PMSI) from 2010 to 2015. We compared incidences of IS in patients with a diagnosis of AF or SND to that in a control group of patients with a main diagnosis of cardiac condition (excluding those with AF or SND, history of stroke and mechanical valve or mitral stenosis).

Results

Of 1,732,412 patients included in the cohort, 1,601,435 (92.44%) had isolated AF, 102,849 (5.94%) had isolated SND and 28,128 (1.62%) had BTS. The control group with cardiac condition included 479,108 patients. Incidence of IS progressively increased when considering patients from the control population, patients with isolated SND, with BTS or with isolated AF (0.67%/yr, 1.95%/yr, 3.03%/yr and 5.48%/yr respectively). These differences were seen in all strata of CHA2DS2VASc score (table). SND patients with a CHA2DS2-VASc score ≥3 had a yearly incidence of IS >2%, comparable to AF population with a CHA2DS2-VASc score ≥1.

Incidence (%/year) of ischemic stroke CHA2DS2-VASc AF population SND population “Control” population Women Men Women Men Women Men All scores 6.72% 4.37% 1.93% 1.96% 0.67% 0.68% Score = 0 – 1.960% – 1.211% – 0.217% Score = 1 2.337% 3.046% 0.538% 1.486% 0.166% 0.345% Score = 2 3.917% 4.499% 0.879% 1.541% 0.298% 0.580% Score = 3 7.572% 4.733% 2.207% 2.084% 0.541% 0.907% Score = 4 7.016% 4.820% 2.363% 2.305% 0.930% 1.278% Score = 5 6.725% 5.345% 2.845% 2.849% 1.249% 1.553% Score = 6 7.637% 7.543% 3.319% 4.109% 1.737% 2.031% Score = 7 10.196% 13.927% 4.663% 7.708% 2.346% 4.089% Score = 8 17.654% 12.607% 8.519% 11.904% 2.446% 2.355%

Conclusion

Patients with isolated SND had a lower risk of IS than patients with AF or BTS. However, SND patients had a non-neglectable risk of IS during follow-up which was higher than in a “control” population. Whether oral anticoagulation may bring a significant clinical benefit might be studied in patients with SND at highest risk of IS.

4070Clinical impact of mitral regurgitation before or following transcatheter aortic valve replacement in patients with aortic stenosis: a nationwide multivariable analysis

Methods

Based on the French administrative hospital-discharge database, the study collected information for all consecutive patients with aortic stenosis treated with transfemoral TAVR in France between 2008 and 2018. Cox regression was used for the analysis of predictors of events during follow-up.

Results

A total of 47,872 patients with transfemoral TAVR were included in the analysis (mean age 83±7 years). Moderate/severe MR was present at baseline (MRb) in 9.5% of the patients. Few patients (1.6%) revealed moderate/severe MR post-TAVR (MRpt). Mean follow-up was 1.31±1.61 years. MRb was associated with an increased cardiovascular mortality (Hazard ratio 1.29, 95% CI 1.20–1.39) and total mortality (Hazard ratio 1.15, 95% CI 1.10–1.21). However, MRb was not an independent predictor in multivariable analysis, neither for cardiovascular mortality (adjusted HR 1.06, 95% CI 0.98–1.14) nor for total mortality (adjusted HR 1.01, 95% CI 0.96–1.07). MRpt was not a predictor of cardiovascular or total mortality. Older age, male sex, history of pulmonary edema/cardiogenic shock, atrial fibrillation, myocardial infarction, diabetes, renal failure, liver disease, pulmonary disease, previous cancer and anemia at baseline independently predicted mortality during follow-up. All of them (but history of cancer) were also independent predictor of cardiovascular death.

Conclusion

Baseline MR was associated with increased cardiovascular and totality mortality following TAVR but was not an independent predictor of any of them. By contrast, several other predictors of cardiovascular and total mortality were identified. This suggests that MR should not be directly considered to establish the strategy for TAVR decision or for avoiding TAVR-related futility.

P1794Futility risk model development and validation among patients with aortic stenosis treated with transcatheter aortic valve replacement

Methods

Based on the French administrative hospital-discharge database, the study collected information for all consecutive patients with aortic stenosis treated with transfemoral TAVR in France between 2008 and 2018. Multivariate logistic regression was used to select the risk factors of early all-cause death in first year after TAVR procedure (considered as futility) for the overall population. Score points were assigned to each risk factor using the β coefficient. Internal validation was performed by a bootstrap method. Calibration was assessed with the Hosmer-Lemeshow goodness of fit test and accuracy with the C-statistic.

Results

A total of 47,872 patients with transfemoral TAVR were included in the analysis (mean age 83±7 years). Mean follow-up was 1.31±1.61 years and 9,338 deaths were recorded (yearly rate 14.9%), among which 4,562 (49%) occurred in first year after TAVR procedure. The final logistic regression model included older age, male sex, history of hospital stay with heart failure, history of acute pulmonary oedema, atrial fibrillation, previous stroke, vascular disease, diabetes, renal disease, liver disease, pulmonary disease, anemia, history of cancer, metastasis and denutrition,. The area under the curve (AUC) for the score was 0.696 (95% CI 0.688–0.704). This score outperformed frailty index and Charlson comorbidity index for identifying futility. AUC was 0.677 (95% CI 0.669–0.86) for internal validation. The Hosmer–Lemeshow goodness of fit test had a p-value of 0.10 suggesting that the model was accurate. We further divided the model into 4 groups with 5%, 12%, 19% and 30% futility, respectively. The low-risk group consisted of 60% of the patients and the high-risk group consisted of 4% of these patients.

Conclusion

This futility prediction score established from a large nationwide cohort of patients treated with TAVR may provide a relevant insight for optimizing healthcare decision. It may facilitate identification of patients who, despite an apparently successful procedure, have risk of death that may outweigh the benefit of an anticipated TAVR.

66Clinical outcomes after catheter ablation for atrial fibrillation in elderly patients: a French nationwide cohort study

Methods

This French longitudinal cohort study was based on the national hospitalization PMSI (Programme de Médicalisation des Systèmes d'Information) database covering hospital care from the entire population. We included all patients, over 18 years old, with AF from January 2010 to December 2015.

Results

Among the 1,663,284 patients identified with AF, 28,018 patients were treated with AF ablation (28% female, mean age 60±10 yo) and 1,635,266 did not have AF ablation (48% female, mean age 78±11 yo). Among those treated with AF ablation, 1,605/28,018 patients (5.7%) were aged >75 yo.

During follow-up (456±546 days), hospitalization with a primary diagnosis of HF and death were recorded. Incidences of hospitalization for HF and death were significantly lower in AF ablation group (respectively 6.09% vs 13.29% person per year, p<0.0001, and 1.49% vs 17.11% person per year, p<0.0001). These associations were confirmed in a multivariable analysis after adjustment on age and other comorbidities (HR 0.66, 95% CI 0.63–0.69, p<0.0001 for HF and HR 0.21, 95% CI 0.19–0.23, p<0.0001 for all-cause death). Results were significant and relatively similar whether patients were aged below or above 75 yo: HR 0.63, 95% CI 0.60–0.66, p<0.0001 when age <75 yo and HR 0.60, 95% CI 0.51–0.70, p<0.0001 when age >75 yo for hospitalization for HF; HR 0.21, 95% CI 0.19–0.24, p<0.0001 when age <75 yo and HR 0.36, 95% CI 0.29–0.45, p<0.0001 when age >75 yo for all-cause death.

Conclusion

In the nationwide analysis of unselected AF patients seen in hospitals, AF ablation was independently associated with a lower risk of hospitalization for HF and death whether patients were aged below or above 75 yo.

P6576Use of atrioventricular nodal ablation after atrial fibrillation ablation failure: a nationwide cohort study

Methods

This French longitudinal cohort study was based on the national hospitalization database covering hospital care from the entire population. The data for all patients admitted in France from January 2010 to December 2015 were collected from the national administrative database, the PMSI (Programme de Médicalisation des Systèmes d'Information). We included all patients, over 18 years old, with AF and at least one AF catheter ablation. Routinely collected medical information includes the principal or secondary diagnoses and procedures performed. Items from the baselines characteristics were pooled into a multivariate Cox model to identify predictors of AV node ablation.

Results

Of 1,663,284 patients identified with AF, 28,018 patients were treated with AF ablation (28% female, mean age 60±10 yo, 22,837 with 1 procedure, 4,576 with 2 procedures and 605 with 3 procedures). Of those 28,018 patients, there were only 369 patients (1.3%) treated with AVNA after a mean follow-up of 374±488 days (median 210, interquartile 15–798). AVNA was less commonly performed than redo AF ablation with 3 procedures, and among these latter patients, only 3.8% were treated with AVNA during follow-up. Most powerful independent predictors of AV node ablation (HR >1.7) were age≥75 yo, heart failure at baseline, abnormal renal function and valve disease. Other independent predictors for AV node ablation (HR 1.2–1.7) were age 65–74 yo, female gender, obesity, coronary artery disease, thyroid disorders, lung disease and hypertension.

Conclusion

Our findings indicate that AVNA is rarely used after AF ablation failure and is probably an underrated strategy in these patients for now. Considering evidence from the APAF-CRT trial indicating a beneficial effect on mortality of this treatment in symptomatic AF patients, a wider use of AVNA should be more widely proposed in these patients. Its optimal timing during rate and rhythm control management still remains to be established.

P4748HASBLED score, frailty index or comorbidity index for bleeding risk assessment in patients with atrial fibrillation?

Background

Charlson comorbidity index (CCI) is a tool to measure comorbid disease status and a strong estimator of mortality. The quantifiable frailty phenotype has also been validated as predictive of mortality and disability. Claims data can be used to classify individuals as frail and non-frail using the Claims-based Frailty Index (CFI). We evaluated whether these tools may help to predict the risk of bleeding in patients with atrial fibrillation (AF).

Methods

All patients with AF seen in an academic institution were identified and followed up for mortality, stroke and bleeding events. HAS-BLED, HEMORR2HAGES, ATRIA and ORBIT scores, CCI and CFI were calculated for each patient. Hazard ratios were calculated and predictive abilities of the scores were compared using the c-statistic in the whole population and then separately in elderly patients (>75 yo).

Results

Among 8962 patients with AF, 274 major bleeding events were recorded during a follow-up of 874±1054 days. Bleeding occurred more commonly in patients with higher bleeding risk scores, CCI and CFI. The 4 bleeding risk scores significantly had lower c-statistics than CCI and CFI for predicting major bleeding (table). Results were similar whether patients were treated with OAC or no OAC. In elderly patients, the c-statistics were all lower and were not significantly different for the 4 scores, CCI and CFI scores (0.594, 0,572, 0.595, 0.594, 0.616 and 0.591 for HAS-BLED, HEMORR2HAGES, ATRIA, ORBIT, CCI and CFI, respectively).

Predictive values for major bleeding ROC Area 95% Conf. Interval P value vs CCI/CFI HASBLED 0.588 0.555–0.621 0.002/0.003 HEMORR2HAGES 0.564 0.531–0.598 <0.0001/<0.0001 ATRIA 0.559 0.522–0.595 <0.0001/<0.0001 ORBIT 0.577 0.542–0.612 0.0002/0.0003 Charlson, CCI 0.652 0.619–0.684 –/0.58 Frailty index, CFI 0.648 0.615–0.681 0.58/–

Conclusion

Comorbidities and frailty, respectively assessed with CCI and CFI, demonstrated statistically better performances in predicting major bleeding than the 4 established bleeding risk scores in AF, although all c-indexes were broadly similar. The 4 bleeding risk scores, CCI and CFI showed lower performance in predicting bleeding within elderly patients in whom they all performed equally to predict bleeding events. Given their simplicity and similar performances, the user-friendly bleeding risk scores remain attractive tools for the estimation of bleeding risk in elderly patients with AF.

High-resolution crystal structures of two crystal forms of human cyclophilin D in complex with PEG 400 molecules

Cyclophilin D (CypD) is a key mitochondrial target for amyloid-β-induced mitochondrial and synaptic dysfunction and is considered a potential drug target for Alzheimer's disease. The high-resolution crystal structures of primitive orthorhombic (CypD-o) and primitive tetragonal (CypD-t) forms have been determined to 1.45 and 0.85 Å resolution, respectively, and are nearly identical structurally. Although an isomorphous structure of CypD-t has previously been reported, the structure reported here was determined at atomic resolution, while CypD-o represents a new crystal form for this protein. In addition, each crystal form contains a PEG 400 molecule bound to the same region along with a second PEG 400 site in CypD-t which occupies the cyclosporine A inhibitor binding site of CypD. Highly precise structural information for CypD should be extremely useful for discerning the detailed interaction of small molecules, particularly drugs and/or inhibitors, bound to CypD. The 0.85 Å resolution structure of CypD-t is the highest to date for any CypD structure.

Influence of preservation solution on early graft failure in clinical lung transplantation

The aim of this study was to assess the influence of preservation solution type and extra- or intracellular composition on the occurrence of early graft dysfunction after clinical lung transplantation. For 170 patients who underwent a single (n = 124) or bilateral (n = 46) lung transplantation in two centers in Paris between 1988 and 1999, the preservation technique applied to the donor lung was single-flush perfusion of the pulmonary artery with one of several solutions of intracellular (Euro-Collins, n = 61; University of Wisconsin, n = 24) or extracellular composition (Cambridge, n = 64; Celsior, n = 21). The early postoperative outcome of these patients was reviewed. Reimplantation edema occurred in 48% of all patients, and the overall 1-mo survival rate was 84%. No significant difference in the incidence of edema, duration of mechanical ventilation, and 1-mo survival rate was observed between the four groups or between intra- and extracellular groups. After adjustment for graft ischemic time by means of multivariate analysis, the use of extracellular preservation fluid was associated with a lower incidence of reimplantation edema without effect on 1-mo mortality. Graft ischemic time was associated with both edema occurrence and 1-mo survival rate (p = 0.02 and p = 0.01, respectively). We conclude that extracellular-type solutions are associated with better lung preservation than intracellular-type solutions in clinical transplantation.

[Massive hemoptysis during sarcoidosis]

Hemoptysis is a rare but often severe event in sarcoidosis. It usually occurs in patients with advanced, fibrotic lung disease. We herein report the case of a 36-year old female patient with type II pulmonary sarcoidosis who presented with abundant hemoptysis very early during the course of her disease. Two attempts to embolize bronchial arteries remained unsuccessful and surgery was eventually required to stop the bleeding. Clinical, microbiological, radiological and pathological data indicate that haemoptysis was caused by systemic hypervascularization around sarcoidosis granuloma.

The seroprevalence of antibodies to toxoplasma gondii in domestic goats in Uganda

Only limited epidemiological information is available on the seroprevalence of Toxoplasma gondii in domestic livestock in sub-Saharan Africa. In Uganda, goats are important to the local economy and are also popular food animals. A high incidence of T. gondii infection in goats would have implications both for animal production and for public health, but no data is available on Toxoplasma infection in these animals. In this study we estimated the seroprevalence of antibodies against T. gondii in goats located in both urban and rural environments and from different geographical regions within Uganda. Goat sera were collected using a random, two-stage clustering method. Of 784 samples analysed by antibody-ELISA from various districts in Uganda, 240 tested positive. The combined (cluster-adjusted) seroprevalence was 0.31 (31%) (95% confidence intervals 0.28, 0.34) indicating a substantial level of infection in these regions. Seroprevalence was significantly higher in goats from urban locations. A strong positive relationship between age and seroprevalence was demonstrated and a mathematical model based on continuous exposure proved generally accurate in predicting seroprevalence. Farm environments were identified as being suitable for oocyst survival and transmission, and the reported incidence of caprine abortion was high. The importance of toxoplasmosis to goat production in Uganda has yet to be determined, but the high seroprevalence detected in this study suggests that it may have a significant impact and that the consumption of goat meat may play a role in zoonotic transmission to humans.

Nebulized cyclosporine in the rat: assessment of regional lung and extrapulmonary deposition

BACKGROUND

Nebulized cyclosporine (CsA) has been shown to limit lung allograft rejection as well as intramuscular (IM) CsA, with limited blood diffusion. The present study determined the pharmacokinetic parameters of nebulized CsA, by the assessment of regional lung deposition and extrapulmonary diffusion of CsA.

METHODS

CsA was given either by IM injection (10 mg/kg) or by aerosol (at 10 and 25 mg/kg doses); 70 rats were killed at 25 and 50 min, and at 2, 4, 6, 8, 12, 24, or 48 hr after CsA administration. CsA levels were measured in the whole lung, in central and peripheral parts of the lung, in whole blood, kidney, and heart. The areas under the concentration time curves (AUCs) were determined.

RESULTS

In blood, kidney, and heart, CsA levels were significantly higher for IM than for aerosol administrations at 10 and 25 mg/kg doses. In the whole lung, the AUC was greater for the aerosol route at 25 mg/kg doses (588 ng x hr/mg) than for the low-dose (200 ng x hr/mg) or IM administration (200 ng x hr/mg). The central to peripheral index of CsA (ratio of AUC central/peripheral part of the lung) was not significantly different for both aerosol administrations (0.63 and 0.69, respectively) and for the IM route (0.81).

CONCLUSIONS

Nebulized CsA allows better pulmonary concentration than IM administration, with equivalent central and peripheral deposition whatever the mode of administration, and results in lower levels in blood, kidney, and heart.

[Report of 2 cases of pleural recurrences of surgically treated bronchogenic carcinoids. Diagnostic and therapeutic problems]

Recurrence after surgery for bronchial carcinoid tumors is very uncommon in cases of typical tumors and occasionally seen in cases of atypical tumors. We observed two cases of recurrence in an unusual location, the pleura. Somatostatin analog and MIBG scinigrams were useful for diagnosis. Treatment required surgical excision of the relapsing tumor, cytoreductive hepatic surgery or hepatic arterial chemoembolization for liver metastases, chemotherapy, interferon, radionuclide therapy, and somatostatin analogs for carcinoid syndrome.

Modulation of ET-1-induced contraction of human bronchi by airway epithelium-dependent nitric oxide release via ET(A) receptor activation

1. The purpose of this work was to investigate whether endothelin-1 (ET-1) was able to induce the release of an inhibitory factor from the airway epithelium in isolated human bronchi and to identify this mediator as well as the endothelin receptor involved in this phenomenon. 2. In intact bronchi, ET-1 induced a concentration-dependent contraction (-logEC50 = 7.92+/-0.09, n = 18) which was potentiated by epithelium removal (-logEC50 = 8.65+/-0.11, n = 17). BQ-123 , an ET(A) receptor antagonist, induced a significant leftward shift of the ET-1 concentration-response curve (CRC). This leftward shift was abolished after epithelium removal. 3. L-NAME (3 x 10(-3) M), an inhibitor of nitric oxide (NO) synthase, induced a significant leftward shift of the ET-1 CRC, and abolished the potentiation by BQ-123 (10(-8) M) of ET-1-induced contraction. 4. In intact preparations, the ET(B) receptor antagonist BQ-788 induced only at 10(-5) M a slight rightward shift of the ET-1 CRC. In contrast, in epithelium-denuded bronchi or in intact preparations in the presence of L-NAME, BQ-788 displayed a non-competitive antagonism toward ET-1-induced contraction. 5. IRL 1620, a selective ET(B) receptor agonist, induced a contraction of the isolated bronchus (-logEC50=7.94+/-0.11, n= 19). This effect was not modified by epithelium removal or by BQ-123. BQ-788 exerted a competitive antagonism against IRL 1620 which was similar in the presence or absence of epithelium. 6. These results show that ET-1 exerts two opposite effects on the human airway smooth muscle. One is contractile via ETB-receptor activation, the other is inhibitory and responsible of NO release which counteracts via ETA-receptor activation the contraction.

[Tracheal resection-anastomosis for iatrogenic stenosis. Experience in 340 cases]

Since 1975, 340 patients were treated by tracheal sleeve resection for tracheal or subglottic laryngeal iatrogenic stenoses in our unit. Preoperative iterative Nd YAG laser sessions have usually been performed, without success. The length of the sleeve specimen was an average of 3 1/4 cm. Twelve patients died on the post operative course (3.5%), 3 more patients died later after failure of the procedure (0.9%) and nineteen had recurrent stenoses treated with use of a tracheostomy tube, a permanent Montgomery tube, or an endotracheal stent (5.6%). Three hundred and six patients are definitely cured (90%), at the first attempt for 265 patients, after a laser session for granulomas for 20 patients, after a second tracheal resection for 6 patients and after a temporary Montgomery tube for 15 patients. Providing there is a good selection of the patients, tracheal sleeve resection is the best treatment for iatrogenic stenosis.

[Reduction of native lung volume after single-lung transplantation for emphysema]

We report three cases of volume reduction surgery in three single lung transplant recipients with emphysema. Each patient had a late decline in lung function with hyper-inflation of the native lung. Lung function was improved post-operatively for two patients. The relief of thoracic overdistension may be considered in single lung transplant recipients who exhibit clinical significant functional deterioration.

Preparation of high-risk patients for major thoracic surgery

For a least a decade, many patients have benefitted from new indications of major thoracic surgery owing to improvements in the surgical and anesthetic procedures of thoracic surgery. Identification of risk factors of perioperative morbidity and mortality becomes of paramount importance when trying to lesson the postoperative mortality rate to 1% or less. The careful assessment of the candidates for thoracic surgery with a multidisciplinary approach is the cornerstone of such an objective. The lower mortality rate should be achievable with a preoperative preparation of the patients of a rehabilitation and nutritional program and a pharmacologic treatment optimization.

Contractile effect of 6 beta-acetoxy nortropane on human and guinea pig airways

AIM

To study the effects of 6 beta-acetoxy nortropane (6 beta-AN) on the isolated human bronchus and guinea pig trachea.

METHODS

The contractile effect of 6 beta-AN was studied with 4 different muscarinic receptor antagonists on airway strips and inositol phosphates (IP) accumulation in human bronchi was determined by HPLC with radioactivity flow detector.

RESULTS

(1) The maximal contractile effect of 6 beta-AN was lower than that of acetylcholine (ACh) on the human bronchus and equal to that of ACh on the guinea pig trachea. 6 beta-AN was more potent than ACh on both preparations (68 and 245 times, respectively). (2) The contractile effect of 6 beta-AN was inhibited by atropine (1 -100 nmol.L-1) or para-fluoro-hexahydro-sila-difenidol (0.01-1 mumol.L-1), but not by methoctramine (Met, 0.3-3 mumol.L-1) or pirenzepine (0.01-0.1 mumol.L-1), and was not enhanced by tacrine (0.1-10 mumol.L-1) or by epithelium removal. (3) The 6 beta-AN induced-contraction was accompanied by an increase of IP levels in isolated human bronchial tissues. (4) 6 beta-AN had an inhibitory effect on isoprenaline (Iso)-induced relaxation, which was abolished or reduced by Met 0.3 mumol.L-1.

CONCLUSION

6 beta-AN exerts a potent contractile effect involving muscarinic M3 receptor stimulation on airway smooth muscle. Muscarinic M2 receptor stimulation is furthermore partially involved in the antagonism by 6 beta-AN on the Iso-induced relaxation of the guinea pig trachea.

Double lung transplantation without cardiopulmonary bypass: arterial to end-tidal carbon dioxide partial pressure differences

Bilateral lung transplantation without cardiopulmonary bypass consists of two sequential single lung transplantations. Variations in ventilatory status during the procedure led us to study the (PaCO2-PE'CO2) gradient to see if PE'CO2 might reflect PaCO2. The gradient was studied in 14 patients at six times during operation. (PaCO2-PE'CO2) (kPa) was mean 1.97 (SD 0.7) after induction, 3.2 (1.4) during single lung ventilation, 1.9 (1.1) after clamping of the contralateral pulmonary artery, 2.96 (1.6) after ventilation and vascularization of the first transplant and the remaining native lung, 0.99 (0.8) during single lung ventilation with the first transplant and 1.3 (0.8) during ventilation of both transplants. With ventilation by the allograft lung(s) alone, the small (PaCO2-PE'CO2) value demonstrated improvement in ventilatory status, enabled PaCO2 to be assessed by PE'CO2 and demonstrated efficiency of the grafts.

Single lung transplantation for pulmonary lymphangiomyomatosis. Unexpected need for extracorporeal circulation

The present case describes an acute respiratory-related hemodynamic failure during a single left lung transplantation in a 32-year-old woman suffering from end-stage pulmonary lymphangiomyomatosis. During the first 5 min of single right lung ventilation, a progressive increase in airway pressure and decrease in tidal volume associated with a decrease in arterial pressure and Spo2 occurred that were successfully countered by reventilation of the left lung. Proper positioning of the double-lumen tube was confirmed with a fiberoptic bronchoscope. Despite deliberate hypoventilation, within a few respiratory cycles, each further attempt at single lung ventilation was followed by abrupt hypotension, increase in pulmonary artery pressure, while airway pressure rose and tidal volume collapsed. The surgical team saw no signs of right pneumothorax. In these circumstances, cardiopulmonary bypass was required to perform pneumonectomy and grafting. Postoperatively a right anterior pneumothorax remained undiscovered on standard radiograph but was later revealed on soft radiograph. This acute intraoperative respiratory failure could equally well have been related to air trapping, in which case, however, deliberate hypoventilation would have been effective. In addition, the striking difference between the progressive onset of the first episode of hemodynamic failure and the immediate onset of the others argues in favor of a pneumothorax being at cause. Patients with pulmonary lymphangiomyomatosis are at high risk for intraoperative pneumothorax, but in our case, it could not be confirmed and treated during the surgical procedure without putting the patient at high risk for lung injury because of pleurodesis due to earlier pleural abrasion. This case again clearly shows the need to have cardiopulmonary bypass whenever single lung transplantation is performed.

Interpleural infusion of 2% lidocaine with 1:200,000 epinephrine for postthoracotomy analgesia

The value of intrapleural analgesia after thoracotomy is still controversial. We investigated the pharmacokinetics of interpleural analgesia in 14 patients with and without thoracic drainage (Groups TD+ and TD-, respectively) to determine the safety of the technique. The infusion led to a high steady-state concentration (Css) of 5.91 +/- 2.46 mg/mL in Group TD-. We then performed a placebo-controlled double-blind study on 16 patients to evaluate the analgesic effects of an interpleural infusion of 2% lidocaine using intravenous patient-controlled analgesia (PCA) with morphine and a visual analog scale score (VAS). In both studies an initial bolus of 3 mg/kg of 2% lidocaine was followed by an infusion of 1 mg.kg-1.h-1 for 48 h. The VAS score was slightly reduced after the bolus (6.6 +/- 1.0 vs 8.7 +/- 0.3; P < 0.05 vs the placebo group) but the cumulative doses of morphine were similar in both groups. There was a slight, but not sustained, improvement in pulmonary function test. In conclusion, interpleural analgesia by continuous infusion of lidocaine is poor after thoracotomy and may lead to blood levels in the toxic range.

Bilateral pulmonary lobe transplantation: left lower and right middle and lower lobes

It is difficult to find lungs of appropriate size for double-lung transplantation in teenagers and small adults. Nevertheless, many young patients suffering from cystic fibrosis are waiting for lung transplantation. We have performed two bilateral lobar transplantations (left lower lobe plus right middle and lower lobe) with good recovery. Details of the technique are described.