CAT scanning for the Detection of Coronary Artery Disease in Patients with IPF

Patients with idiopathic pulmonary fibrosis (IPF) have a higher prevalence of coronary artery disease and this could have an impact on their outcomes. We investigated the predictive ability of coronary artery calcification, assessed by routine CT, which may predict the presence of coronary artery disease. METHODS:
The study cohort consisted of patients with IPF and with left heart catheterization data plus CT scans from July 2003 to July 2008. Grades of coronary calcification on CT were compared with left heart catheterization determination of coronary artery disease. RESULTS:
There were 57 patients in whom left heart catheterization review demonstrated significant coronary artery disease in 28.1% (16/57), mild disease in 40.3% (23/57) and none in 31.6% (18/57). The median time interval between the catheterization and the reviewed CT scan was 39 days. The sensitivity of moderate to severe calcification for significant coronary artery disease was 81%, while the specificity was 85%, with an associated odds ratio of 25.2 (4.64-166, P < 0.005). There was excellent agreement among three radiologists in the grading of coronary calcification. CONCLUSIONS: Coronary calcification, as assessed by routine CT of the chest, has very good performance characteristics in predicting underlying significant coronary artery disease in patients with IPF. The routine availability of this study enables the ready screening for coronary artery disease in IPF patients. ...

Supranormal Expiratory Airflow after Bilateral Lung Transplantation is Associated with Improved Survival

flow volume loops (FVL) in some bilateral lung transplant (BLT) and heart-lung transplant (HLT) patients suggest variable extrathoracic obstruction in the absence of identifiable causes. These FVLs usually have supranormal expiratory and normal inspiratory flow rates (SUPRA pattern). OBJECTIVES:
characterize the relationship of the SUPRA pattern to predicted donor and recipient lung volumes, airway size, and survival. METHODS:
we performed a retrospective review of adult BLT/HLT patients. We defined the SUPRA FVL pattern as: (1) mid-vital capacity expiratory to inspiratory flow ratio (Ve50:Vi50) > 1.0, (2) absence of identifiable causes of extrathoracic obstruction, and (3) Ve50/FVC ≥ 1.5 s(-1). We calculated predicted total lung capacity (pTLC) ratio by dividing the donor pTLC by the recipient pTLC. We measured airway luminal areas on thoracic computer tomographic scans. We compared survival in patients with and without the SUPRA pattern. MEASUREMENTS AND MAIN RESULTS:
the SUPRA FVL pattern occurred in 56% of the 89 patients who qualified for the analysis. The pTLC ratio of SUPRA and non-SUPRA patients was 1.11 and 0.99, respectively (P = 0.004). A higher pTLC ratio was correlated with increased probability of the SUPRA pattern (P = 0.0072). Airway luminal areas were larger in SUPRA patients (P = 0.009). Survival was better in the SUPRA cohort (P = 0.009). CONCLUSIONS:
the SUPRA FVL pattern was frequent in BLT/HLT patients. High expiratory flows in SUPRA patients could result from increased lung elastic recoil or reduced airway resistance, both of which could be caused by the pTLC mismatch. Improved survival in the SUPRA cohort suggests…

Heart Rate Recovery after 6MWT Predicts Pulmonary Hypertension in Patients with IPF

In patients with IPF, we sought to validate that abnormal heart rate recovery at 1 min (HRR1) after six-minute walk test (6MWT) predicts mortality and to explore the relationship between abnormal HRR1 and pulmonary hypertension (PH). METHODS:
We identified IPF patients who performed a 6MWT as part of their clinical evaluation between 2006 and 2009 and were followed to lung transplantation or death. Right heart catheterization (RHC) data were collated and analysed for the subgroup who had this procedure. RESULTS:
There were 160 subjects who qualified for the survival analysis, and those with an abnormal HRR1 had worse survival than subjects with normal HRR1 (log-rank P = 0.01). Eighty-two subjects had a right heart catheter (RHC); among them, abnormal HRR1 was associated with RHC-confirmed PH (χ(2) = 4.83, P = 0.03) and had a sensitivity, specificity, positive predictive value and negative predictive value of 52%, 74%, 41% and 82%, respectively, for PH. In bivariate and multivariable analyses, abnormal HRR1 appeared to be the strongest predictor of RHC-confirmed PH (odds ratio (OR) = 4.0, 95% CI: 1.17-13.69, P = 0.02 in the multivariable analysis). CONCLUSIONS:
This study adds to data that support the validity of abnormal HRR1 as a predictor of mortality and of RHC-confirmed PH in IPF. Research is needed to further investigate the link between abnormal HRR1 and PH and to elucidate heart-lung interactions at work during exercise and recovery in patients with IPF. …

The HLA Class II Allele Allele DRB1*15 is over-represented in patients with Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive and medically refractory lung disease with a grim prognosis. Although the etiology of IPF remains perplexing, abnormal adaptive immune responses are evident in many afflicted patients. We hypothesized that perturbations of human leukocyte antigen (HLA) allele frequencies, which are often seen among patients with immunologic diseases, may also be present in IPF patients. METHODS/PRINCIPAL FINDINGS:
HLA alleles were determined in subpopulations of IPF and normal subjects using molecular typing methods. HLA-DRB1*15 was over-represented in a discovery cohort of 79 Caucasian IPF subjects who had lung transplantations at the University of Pittsburgh (36.7%) compared to normal reference populations. These findings were prospectively replicated in a validation cohort of 196 additional IPF subjects from four other U.S. medical centers that included both ambulatory patients and lung transplantation recipients. High-resolution typing was used to further define specific HLA-DRB1*15 alleles. DRB1*1501 prevalence in IPF subjects was similar among the 143 ambulatory patients and 132 transplant recipients (31.5% and 34.8%, respectively, p = 0.55). The aggregate prevalence of DRB1*1501 in IPF patients was significantly greater than among 285 healthy controls (33.1% vs. 20.0%, respectively, OR 2.0; 95%CI 1.3-2.9, p = 0.0004). IPF patients with DRB1*1501 (n = 91) tended to have decreased diffusing capacities for carbon monoxide (DL(CO)) compared to the 184 disease subjects who lacked this allele (37.8±1.7% vs. 42.8±1.4%, p = 0.036). CONCLUSIONS/SIGNIFICANCE:
DRB1*1501 is more prevalent among IPF patients than normal subjects, and may be associated with greater impairment of gas exchange. These data are novel evidence that immunogenetic processes can play a role in…

Long-term Course and Prognosis of Idiopathic Pulmonary Fibrosis in the Modern Era

The American Thoracic Society and European Respiratory Society guidelines for the diagnosis and treatment of idiopathic pulmonary fibrosis (IPF) have been published recently. However, the influence, practical application, and utility of the prior consensus statement for IPF have never been evaluated. Demographics, diagnostic criteria, pulmonary function data, and disposition of patients with IPF evaluated at an interstitial lung disease center between 2000 and 2009 were analyzed. Enrollment in clinical drug trials, lung transplantation, and mortality also were assessed. A total of 521 patients with IPF were evaluated, with pulmonary function testing available in 446. In the 64% of patients without surgical lung biopsy, the most common major criterion not fulfilled was bronchoscopy. Lung transplantation was performed in 16.1% of patients, whereas 27.4% of prescreened patients were enrolled in a prospective drug study. Patients with mild, moderate, and severe disease categorized by FVC % predicted had median survivals of 55.6, 38.7, and 27.4 months, respectively. The attrition rate of patients who survived beyond 5 years was attenuated in subsequent years. IPF remains a deadly disease with a poor prognosis. Bronchoscopy does not appear to be required for an accurate diagnosis. A minority of patients were accommodated within a clinical trial or with transplantation. Categorization by baseline FVC % predicted effectively discriminates groups with different long-term outcomes. Our analysis supports the view that the value of statements also can be realized in the subsequent demonstration of their impact on patient management, which might enable further refinements in a continuous, iterative rediscovery process….

Parameters of donor-recipient mismatch and survival after bilateral lung transplantation

The purpose of this study was to investigate the relationship between donor-recipient height, gender and predicted estimates of total lung capacity (pTLC) mismatches and post-transplant survival. METHODS:
The lung transplant databases at three programs were reviewed. The pTLC ratios (donor pTLC/recipient pTLC) and height ratios (donor height/recipient height) were calculated retrospectively. Patients were grouped according to pTLC ratio ≤1.0 or >1.0 and height ratio ≤1.0 or >1.0, and according to gender (mis-)matching. A time-to-event analysis was performed for risk of death after transplantation conditional on 30-day survival using Kaplan-Meier survival and Cox proportional hazard models. RESULTS:
There were 211 adult bilateral lung transplant recipients who qualified for the analysis. Mean follow-up was comparable for all cohorts (range 2.21 to 3.85 years). In the univariate Cox proportional hazard models, a pTLC ratio >1.0 (HR 0.43, p = 0.002) and a height ratio >1.0 (HR 0.61, p = 0.03) were associated with better survival, and a female-donor-to-male-recipient gender mismatch (F-to-M) was associated with worse survival (HR 2.35, p = 0.01). In the multivariate Cox proportional hazard model accounting for F-to-M gender mismatch and height ratio >1.0, a pTLC ratio >1.0 remained associated with survival (HR 0.38, p = 0.015). However, accounting for a pTLC ratio >1.0, a height ratio of >1.0 and F-to-M mismatch were not associated with survival. CONCLUSIONS:
A pTLC ratio >1.0 is associated with improved survival after bilateral lung transplantation. The pTLC ratio might better reflect allograft-thorax mismatch than the height ratio, as it also accounts for effects of gender on lung…

Lung Size Mismatch in Bilateral Lung Transplantation Is Associated With Allograft Function and Bronchiolitis Obliterans Syndrome

Size mismatch between donor lungs and a recipient thorax could affect the major determinants of maximal expiratory airflow: airway resistance, propensity of airways to collapse, and lung elastic recoil. METHODS:
A retrospective review of 159 adults who received bilateral lung transplants was performed. The predicted total lung capacity (pTLC) for donors and recipients was calculated based on sex and height. Size matching was represented using the following formula: pTLC ratio = donor pTLC / recipient pTLC. Patients were grouped according to those with a pTLC ratio > 1.0 (oversized) or those with a pTLC ratio ≤ 1.0 (undersized). Allograft function was analyzed in relation to the pTLC ratio and to recipient and donor predicted function. RESULTS:
The 96 patients in the oversized cohort had a mean pTLC ratio of 1.16 ± 0.13 vs 0.89 ± 0.09 in the 63 patients of the undersized group. At 1 to 6 months posttransplant, the patients in the oversized cohort had higher FEV(1)/FVC ratios (0.895 ± 0.13 vs 0.821 ± 0.13, P < .01) and lower time constant estimates of lung emptying (0.38 ± 0.2 vs 0.64 ± 0.4, P < .01) than patients in the undersized cohort. Although the FVCs expressed as % predicted for the recipient were not different between cohorts, the FVCs expressed as % predicted for the donor organ were lower in the oversized cohort compared with the undersized cohort (at 1-6 months, 52.4% ± 17.1% vs 65.3% ± 18.3%, P < .001). Kaplan-Meier estimates for the occurrence of bronchiolitis obliterans syndrome...

Pulmonary Complications of Lung Transplantation

Lung transplantation is an effective treatment option for select patients with a variety of end-stage lung diseases. Although transplant can significantly improve the quality of life and prolong survival, a myriad of pulmonary complications may result in significant morbidity and limit long-term survival. The recognition and early treatment of these complications is important for optimizing outcomes. This article provides an overview and update of the pulmonary complications that may be commonly encountered by pulmonologists caring for these patients. …

Parenchymal trafficking of pleural mesothelial cells in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is characterised by myofibroblast proliferation leading to architectural destruction. Neither the origin nor the continued proliferation of myofibroblasts is well understood. Explanted human IPF lungs were stained by immunohistochemistry for calretinin, a marker of pleural mesothelial cells (PMCs). Chronic obstructive pulmonary disease (COPD) and cystic fibrosis (CF) lungs acted as controls. The number of PMCs per 100 nucleated cells and per photomicrograph was estimated along with the Ashcroft score of fibrosis. Mouse PMCs expressing green fluorescent protein (GFP) or labelled with nanoparticles were injected into the pleural space of mice given intranasal transforming growth factor (TGF)-β1. Mouse lungs were lavaged and examined for the presence of GFP, smooth muscle α-actin (α-SMA) and calretinin. Calretinin-positive PMCs were found throughout IPF lungs, but not in COPD or CF lungs. The number of PMCs correlated with the Ashcroft score. In mice, nanoparticle-laden PMCs were recoverable by bronchoalveolar lavage, depending on the TGF-β1 dose. Fluorescent staining showed α-SMA expression in GFP-expressing PMCs, with co-localisation of GFP and α-SMA. PMCs can traffic through the lung and show myofibroblast phenotypic markers. PMCs are present in IPF lungs, and their number correlates with IPF severity. Since IPF presumably begins subpleurally, PMCs could play a pathogenetic role via mesothelial-mesenchymal transition …