Size-matching in lung transplantation by computed tomography for end-stage interstitial disease: a retrospective analysis.

Background: Size matching between donors and recipients is a major issue in lung transplantation (LTx), especially in patients with restrictive lung disease (RLD). This study aims to evaluate computed tomography (CT) as an additional method for defining the total lung capacity (TLC) in patients with end-stage interstitial disease awaiting LTx. Methods: Clinical data and CT scans from patients who underwent a first LTx from January 2014 to July 2018 in Bichat Hospital, Paris, were prospectively included in a database. CT TLC (ctTLC) was retrospectively calculated after semi-automatic contouring of the parenchyma and compared with measured TLC (mTLC) and predicted TLC (pTLC) values. Results: The study group included 89 patients (male:female =68:21; mean age, 59.5±10.0 years). The time between pulmonary function tests (PFTs) and CT scan was 162±270 days [median, 67 days; interquartile range (IQR), 0-233 days]. ctTLC was inferior to mTLC and pTLC (respectively 2,979±1,001 mL, 3,530±1,077 and 6,381±955 mL, P<0.001). The relative difference between CT lung volume (ctLV) and measured lung volume (mLV) was higher on the left than on the right side (25.4% vs. 16.3%, respectively, P=0.11). After exclusion of two outliers, we found a significant correlation between ctTLC and mTLC (r=0.762, P<0.001). Conclusions: CT volume is a feasible method to assess TLC in patients with end-stage interstitial disease awaiting LTx. This study highlights potential size-mismatch for graft selection before LTx and opens the perspective of a prospective trial evaluating impact of size-matching by donor-recipient (D-R) ctTLC ratio on postoperative outcomes.

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.

Surgical revascularization of the celiac artery for persistent intestinal ischemia in short bowel syndrome.

BACKGROUND AND OBJECTIVES: Without prompt superior mesenteric artery (SMA) revascularization, acute mesenteric ischemia (AMI) frequently leads to death or short bowel syndrome (SBS). In SBS patients, persistent or chronic intestinal ischemia (PII) of the remnant bowel can lead to recurrences of AMI. Since SMA revascularization is sometimes unfeasible, celiac artery (CA) revascularization may improve blood supply to the remnant bowel. The aim of this study was to describe and to assess our experience of the CA revascularization in case of SMA occlusion unsuitable for revascularization in the setting of PII in SBS patients. METHODS: All consecutive patients with i) SBS consecutive to AMI, ii) persistent intestinal ischemia (PII), iii) irreversible SMA occlusion, i.e unsuitable for radiological or surgical revascularization and iv) occlusion or severe stenosis of the CA were included. RESULTS: Thirteen patients (7 males/6 females, mean age = 47.2 ±â€¯12.1 years) were included. The mean length of remnant small bowel was 47 ±â€¯39 cm and 77% of patients had a stoma. The types of revascularization included anterograde aorto-hepatic bypass n = 11 (84%), ilio-hepatic bypass n = 1 (8%) and endarterectomy n = 1 (8%). Major adverse events were observed in 5 cases: bypass graft infection (n = 2), hemorrhagic pericarditis (n = 2), hemorrhagic shock (n = 2) and aortic false aneurysm (n = 1). After a mean follow-up of 27.0 ±â€¯25.2 months, symptoms of PII relieved in 12 cases (92%) allowing for digestive surgical rehabilitation with continuity restoration in 7 patients (54%). PN was weaned for 2 patients. One-year and 3-year survival rates were 73.8% and 73.8% respectively. No recurrence of AMI or further need for bowel resection was noticed. CONCLUSION: For patients with SBS suffering from PII with CA occlusion or stenosis without possibility of SMA revascularization, the surgical revascularization of the CA allowed digestive rehabilitation with acceptable morbidity and mortality rates.

Standard and Strain Measurements by Echocardiography Detect Early Overloaded Right Ventricular Dysfunction: Validation against Hemodynamic and Myocyte Contractility Changes in a Large Animal Model.

BACKGROUND: Early detection of right ventricular (RV) failure is required to improve the management of patients with congenital heart diseases. The aim of this study was to validate echocardiography for the early detection of overloaded RV dysfunction, compared with hemodynamic and myocyte contractility assessment. METHODS: Using a porcine model reproducing repaired tetralogy of Fallot, RV function was evaluated over 4 months using standard echocardiography and speckle-tracking compared with hemodynamic parameters (conductance catheter). Sarcomere shortening and calcium transients were recorded in RV isolated myocytes. Contractile reserve (ΔEmax) was assessed by ß-adrenergic stimulation in vivo (dobutamine 5 µg/kg) and ex vivo (isoproterenol 100 nM). RESULTS: Six operated animals were compared with four age- and sex-matched controls. In the operated group, hemodynamic RV efficient ejection fraction was significantly decreased (29.7% [26.2%-34%] vs 42.9% [40.7%-48.6%], P < .01), and inotropic responses to dobutamine were attenuated (ΔEmax was 51% vs 193%, P < .05). Echocardiographic measurements of fraction of area change, tricuspid annular plane systolic excursion, tricuspid annular peak systolic velocity (S') and RV free wall longitudinal systolic strain and strain rate were significantly decreased. Strain rate, S', and tricuspid annular plane systolic excursion were correlated with ΔEmax (r = 0.75, r = 0.78, and r = 0.65, respectively, P < .05). These alterations were associated in RV isolated myocytes with the decrease of sarcomere shortening in response to isoproterenol and perturbations of calcium homeostasis assessed by the increase of spontaneous calcium waves. CONCLUSIONS: In this porcine model, both standard and strain echocardiographic parameters detected early impairments of RV function and cardiac reserve, which were associated with cardiomyocyte excitation-contraction coupling alterations.

Diagnostic accuracy of multidetector spiral computed tomography for preoperative assessment of sinus venosus atrial septal defects in children.

OBJECTIVES: To prospectively assess the value of multidetector computed tomography (MDCT) for detecting partial anomalous pulmonary venous return (PAPVR) in children with suspected sinus venosus-atrial septal defect (SV-ASD). METHODS: Forty-four children (mean age, 7.3 years; range, nine months-16 years) from whom transthoracic echocardiography (TTE) was inconclusive for the diagnosis underwent MDCT after contrast medium injection. Diagnosis was suspected on TTE by abnormal pulmonary venous return, no visualization of pulmonary venous ostia, or unexpected dilatation of right cavities. The first 11 children also underwent cardiac catheterization. Surgical findings constituted the diagnostic reference standard. RESULTS: Thirty-two (73%) children had SV-ASD with PAPVR. Of the first 11 patients, one had PAPVR by MDCT and 10 by conventional angiography; these 11 patients had PAPVR by surgery. Of the remaining 33 patients, 21 had SV-ASD and 12 had ostium secundum ASD, by both MDCT and surgery. MDCT had 100% sensitivity, 100% specificity, 100% positive predictive value, and 100% negative predictive value for diagnosing PAPVR in patients with suspected SV-ASD. CONCLUSION: Contrast-enhanced MDCT is a highly accurate, minimally-invasive technique for detecting PAPVR associated with SV-ASD. Contrast-enhanced MDCT may be used safely to replace conventional angiography for the definitive diagnosis and preoperative evaluation of children with suspected SV-ASD.

Slide tracheoplasty in infant with congenital tracheal stenosis and tracheomalacia after esophageal atresia with tracheoesophageal fistula repair.

Slide tracheoplasty can be applied successfully to all types of long segment congenital tracheal stenosis. In case of short segment tracheal stenosis, direct resection and anastomosis is often preferred. We report a case illustrating a new side benefit of the slide tracheoplasty in a patient presenting a relatively short hypoplastic tracheal segment coexisting with tracheomalacia after EA with TEF repair.