Endoscopic narrow-band imaging-quantitative assessment of airway vascularity after lung transplantation.

In lung transplant recipients, the submucosal vascular plexus of the airway wall potentially represents one of the key structures of graft injury. Narrow band imaging is a novel endoscope technique that allows visual enhancement of the mucosa vasculature. It was our aim to investigate the ability of narrow-band imaging in combination with computerized image analysis to quantitatively assess airway vascularity in lung transplant recipients. In consecutive lung transplant recipients, in addition to the routine procedures, optical analysis of the main carina (autologous tissue) and the upper lobe carina (allogeneic tissue) were performed. From every site, three representative pictures were chosen. A total of 63 bronchoscopies were analyzed. The intraclass correlation coefficient (measure for test-retest reliability) of the three measurements were 0.69 and 0.74 for the main carina and the upper lobe carina, respectively. A mixed linear regression revealed increased vascularity in autologous tissue of patients with cystic fibrosis (p=0.06) and decreased vascularity in allogeneic tissue with time after transplantation (p=0.09). Endoscopic narrow-band imaging (NBI) in combination with computerized image analysis allows consistent assessment of airway vascularity in vivo. In lung transplant recipients, there might be differences in airway vascularity in both autologous and allogeneic large airways.

Daytime Cheyne-Stokes respiration in ambulatory patients with severe congestive heart failure is associated with increased mortality.

BACKGROUND: Cheyne-Stokes respiration (CSR) frequently occurs in patients with severe heart failure during sleep and may increase mortality. Daytime CSR supposedly poses an even greater risk, but its prevalence and prognostic importance remain elusive. Therefore, we investigated the circadian prevalence of CSR and its influence on survival in patients with heart failure. METHODS: In 60 consecutive ambulatory patients (mean age+/-SE, 58.0+/-1.5 years; 6 women) with stable severe heart failure (left ventricular ejection fraction, 26+/-1%; New York Heart Association [NYHA] class, 2.6+/-0.1), the breathing pattern was unobtrusively monitored during 24 h of usual activities with a portable respiratory inductive plethysmograph. RESULTS: During nights, 62% of patients had >or=15 periodic breathing cycles per hour; during days, the corresponding prevalence was 16%. CSR prevailed in 32+/-3% of the night and in 10+/-2% of the day, with peaks at 4:00 am, 2:00 pm, and 6:00 pm. Eighteen patients with CSR during >or=10% of the daytime lived shorter without heart transplantation than 42 patients with <10% of daytime CSR (p<0.05) during 836+/-27 days of follow-up. CSR during >or=10% of the daytime was an independent predictor of mortality (hazard ratio, 3.8; 95% confidence interval, 1.1 to 12.7; p<0.05) when controlling for age, sex, brain natriuretic peptide, left ventricular ejection fraction, and NYHA class. CONCLUSIONS: CSR occurs in 62% of patients with severe heart failure at night and in 16% during the day. Since daytime CSR is associated with reduced survival, solely performing sleep studies may not allow to adequately assess prognosis and tailor treatment in patients with severe heart failure.