Does Systemic Sclerosis-associated Interstitial Lung Disease Burn Out? Specific Phenotypes of Disease Progression.

RATIONALE: Previous studies have suggested that interstitial lung disease (ILD) progresses most rapidly early in the course of systemic sclerosis-associated (SSc)-ILD, and that SSc-ILD is often more stable or even "burned out" after the first 4 years following diagnosis. OBJECTIVES: Our objectives were to determine whether an apparent plateau in pulmonary function decline is due to survival bias and to identify distinct prognostic phenotypes of ILD progression. METHODS: Consecutive patients with SSc-ILD from a single center were included. Pulmonary function measurements were typically performed every 6 months. Study participants were categorized into long-term survivors (>8 yr survival from diagnosis), and those with medium-term and short-term mortality (4-8 and <4 yr survival, respectively). We excluded those censored with less than 8 years of follow-up. Subject-specific slopes for change in forced vital capacity (FVC) and diffusing capacity of the lung for carbon monoxide (DlCO) were calculated using generalized linear models with mixed effects. The rate of decline in FVC was compared across prognostic groups. RESULTS: The cohort included 171 study participants with SSc-ILD. A plateau in the progression of FVC was apparent in the full cohort analysis but disappeared with stratification into prognostic subgroups to account for survival bias. Those with short-term mortality had a higher annual rate of decline in FVC (-4.10 [95% confidence interval (CI), -7.92 to -0.28] vs. -2.14 [95% CI, -3.31 to -0.97] and -0.94 [-1.46 to -0.42]; P = 0.003) and DlCO (-5.28 [95% CI, -9.58 to -0.99] vs. -3.13 [95% CI, -4.35 to -1.92] and -1.32 [95% CI, -2.01 to -0.63]; P < 0.001) than those with medium-term mortality and long-term survival with adjustment for age, sex, and pack-years. Change in FVC in the previous year did not predict FVC change in the subsequent year. CONCLUSIONS: Adults with SSc-ILD have distinct patterns of physiological progression that remain relatively consistent during long-term follow-up; however, recent change in FVC cannot be used to predict future change in FVC within shorter follow-up intervals. The findings of this study provide important information on the course of disease in SSc-ILD and identify specific phenotypes of progression that may improve clinical decision-making and design of future therapeutic trials.

Oesophageal diameter is associated with severity but not progression of systemic sclerosis-associated interstitial lung disease.

BACKGROUND AND OBJECTIVE: It is unknown whether oesophageal disease is associated with systemic sclerosis-associated interstitial lung disease (SSc-ILD) severity, progression or mortality. METHODS: High-resolution computed tomography (HRCT) scans from 145 SSc-ILD patients were scored for fibrosis score, oesophageal diameter and presence of hiatal hernia. Fibrosis asymmetry was calculated as: (most affected side - least affected side)/(most affected side + least affected side). Mixed effects models were used for repeated measures analyses. RESULTS: Mean fibrosis score was 8.6%, and most patients had mild-to-moderate physiological impairment. Every 1 cm increase in oesophageal diameter was associated with 1.8% higher fibrosis score and 5.5% lower forced vital capacity (FVC; P ≤ 0.001 for unadjusted and adjusted analyses). Patients with hiatal hernia had 3.9% higher fibrosis score, with persistent differences on adjusted analysis (P = 0.001). Oesophageal diameter predicted worsening fibrosis score over the subsequent year (P = 0.02), but not when adjusting for baseline fibrosis score (P = 0.16). Oesophageal diameter was independently associated with mortality (P = 0.001). Oesophageal diameter was not associated with asymmetric disease or radiological features of gross aspiration. CONCLUSION: Oesophageal diameter and hiatal hernia are independently associated with SSc-ILD severity and mortality, but not with ILD progression or asymmetric disease. Oesophageal disease is unlikely to be a significant driver of ILD progression in SSc.

Comparison of low-dose coronary artery calcium scoring using low tube current technique and hybrid iterative reconstruction vs. filtered back projection.

INTRODUCTION: We sought to validate whether low dose CACS CT with hybrid IR (HIR) could replace standard dose filtered back projection (FBP). METHOD: We enrolled 100 patients to undergo low dose CACS CT with HIR, in addition to routine full dose FBP. RESULTS: No significant difference between full and low dose CT in Agatston score 138.2±360.6 vs. 137.3±356.4 (p=0.272) or calcium mass score 19±48.3 vs. 18.7±49 (p=0.8), respectively. Bland-Altman analysis showed no systematic bias. Calcium volume difference was statistically significant 57.2±134 vs. 55.1±130.2 (p=0.001). CONCLUSION: Low dose CT for calcium scoring with HIR enables stable CACS Agatston score and calcium mass quantification as compared to full dose FBP.

The effect of a whole heart motion-correction algorithm on CT image quality and measurement reproducibility in Pre-TAVR aortic annulus evaluation.

BACKGROUND: Motion correction (MC) algorithms have been shown to improve image quality, interpretability and diagnostic accuracy in coronary CT angiography. We sought to determine whether MC extended to the whole heart would demonstrate improved image quality and reproducibility of aortic annular measurements in pre-TAVR CT. MATERIALS AND METHODS: Twenty-two consecutive contrast enhanced CT data sets acquired for pre TAVR evaluation using retrospective ECG synchronization during a single heart beat were retrospectively identified. Image data sets were obtained from raw data acquired at 35% and 75% of the R-R interval using both standard (STD) and motion corrected (MC) reconstruction algorithms. Four data sets (2 STD, 2 MC) per patient were analyzed by 2 independent, blinded readers for aortic annular area, short and long axis, perimeter and average diameter. Image quality was graded using a 5 point Likert score (1 and 2 non diagnostic, 5 excellent). Statistical analysis was performed using Wilcoxon matched paired tests, Bland-Altman (B-A) plots and Lin's concordance coefficient comparing 35% STD to 35% MC, and 75% STD to 75% MC. RESULTS: Eighty-eight datasets were analyzed (44 STD, 44 MC). At 35%, there was a significant improvement in image quality for MC (Likert score 3.3 ± 0.9 STD vs. 3.9 ± 0.7 MC, p < 0.007). While B-A analysis demonstrated narrower interobserver agreement for aortic annular area (bias 0.03 vs 0.02 cm(2), range -0.32 to 0.39 cm(2) vs -0.50 to 0.55 cm(2)), and perimeter (bias 0.3 vs 0.3 mm, range -3.1 to 3.8 mm vs -4.6 to 5.3 mm), this was not statistically significant by concordance correlation coefficient. At 75%, there was no significant difference in image quality (Likert score 3.3 ± 0.9 vs. 3.5 ± 0.76, p = 0.454) or annular measurement agreement intervals. CONCLUSION: Motion correction algorithms may yield significant improvements of image quality in systolic CT data sets of the heart. Further validation studies are required to determine the effect on annular measurements and translation into clinical practice.