Effects of acute hyperoxia on autonomic function and coronary tone in patients with peripheral artery disease.

Numerous studies have shown that oxidative stress plays an important role in peripheral artery disease (PAD). Prior reports suggested autonomic dysfunction in PAD. We hypothesized that responses of the autonomic nervous system and coronary tone would be impaired in patients with PAD during exposure to acute hyperoxia, an oxidative stressor. In 20 patients with PAD and 16 healthy, sex- and age-matched controls, beat-by-beat heart rate (HR, from ECG) and blood pressure (BP, with Finometer) were recorded for 10 min during room air breathing and 5 min of hyperoxia. Cardiovagal baroreflex sensitivity and HR variability (HRV) were evaluated as measures of autonomic function. Transthoracic coronary echocardiography was used to assess peak coronary blood flow velocity (CBV) in the left anterior descending coronary artery. Cardiovagal baroreflex sensitivity at rest was lower in PAD than in healthy controls. Hyperoxia raised BP solely in the patients with PAD, with no change observed in healthy controls. Hyperoxia induced an increase in cardiac parasympathetic activity assessed by the high-frequency component of HRV in healthy controls but not in PAD. Indices of parasympathetic activity were lower in PAD than in healthy controls throughout the trial as well as during hyperoxia. Hyperoxia induced coronary vasoconstriction in both groups, while the coronary perfusion time fraction was lower in PAD than in healthy controls. These results suggest that the response in parasympathetic activity to hyperoxia (i.e., oxidative stress) is blunted and the coronary perfusion time is shorter in patients with PAD.NEW & NOTEWORTHY Patients with peripheral artery disease (PAD) showed consistently lower parasympathetic activity and blunted cardiovagal baroreflex sensitivity compared with healthy individuals. Notably, hyperoxia, which normally boosts parasympathetic activity in healthy individuals, failed to induce this response in patients with PAD. These data suggest altered autonomic responses during hyperoxia in PAD.

Renal pelvic and ureteral wall thickening in renal cell carcinoma: prevalence, cause, and clinical significance.

PURPOSE: This study was performed to characterize renal pelvic and ureteral wall thickening (PUWT) in renal cell carcinoma (RCC) patients, including prevalence, cause, and detailed radiological findings based on contrast-enhanced CT, and to correlate these features with corresponding pathological findings. MATERIALS AND METHODS: 152 patients pathologically diagnosed with RCC by surgery were included. Two radiologists retrospectively evaluated the presence of PUWT and the radiological characteristics based on CT. Relationships among clinical characteristics, CT findings, and PUWT were evaluated. Pathological findings of PUWT were also investigated. RESULTS: The prevalence of RCC-related PUWT was 10% (N = 15). PUWT was frequently observed in cases with advanced TNM stage. Tumor thrombus, sinus extent, and peritumoral neovascularity were significantly more frequent in cases with PUWT. PUWT was observed at the pelvis or from the pelvis to the upper ureter. Fourteen of 15 cases in which the pelvic/ureteral wall was pathologically investigated did not show any pathological abnormalities. CONCLUSION: The prevalence of PUWT was 10% and most cases were thought to be caused by temporary vascular dilatation in the pelvis and ureter, which is a secondary condition caused by hypervascular RCC, and not a direct result of tumor invasion.

Early detection of intrahepatic cholangiocarcinoma.

Cholangiocarcinoma (CC) is a malignant tumor which arises from the biliary epithelium and most cases represent adenocarcinoma. CC can be classified into intrahepatic CC (ICC), perihilar CC, and distal CC, based on the site of anatomic origin. The incidence of ICC is increasing in both Western and Eastern countries, while that of extrahepatic cholangiocarcinoma remains fairly stable. ICC infiltrates into adjacent nerves and lymphatic vessels, resulting in progressive disease with a poor prognosis; thus, early detection of ICC is critical for achieving better outcomes and providing better patient care. However, it is difficult for clinicians to detect an ICC, especially in its early stage. Different from hepatocellular carcinoma, the lack of surveillance system for the high-risk group of CC does not allow for a reliable screening examination. In this context, for early detection and diagnosis of ICC, radiologists need to know predisposing conditions that can lead to the development of ICC, such as chronic biliary or hepatic inflammation, primary sclerosing cholangitis, congenital biliary diseases, and other conditions. In this article, we discuss and illustrate the radiologic features of ICC with special attention to early disease stages and of predisposing conditions of ICC.