Amphibian and reptile road-kills on tertiary roads in relation to landscape structure: using a citizen science approach with open-access land cover data.

BACKGROUND: Amphibians and reptiles are among the most endangered vertebrate species worldwide. However, little is known how they are affected by road-kills on tertiary roads and whether the surrounding landscape structure can explain road-kill patterns. The aim of our study was to examine the applicability of open-access remote sensing data for a large-scale citizen science approach to describe spatial patterns of road-killed amphibians and reptiles on tertiary roads. Using a citizen science app we monitored road-kills of amphibians and reptiles along 97.5 km of tertiary roads covering agricultural, municipal and interurban roads as well as cycling paths in eastern Austria over two seasons. Surrounding landscape was assessed using open access land cover classes for the region (Coordination of Information on the Environment, CORINE). Hotspot analysis was performed using kernel density estimation (KDE+). Relations between land cover classes and amphibian and reptile road-kills were analysed with conditional probabilities and general linear models (GLM). We also estimated the potential cost-efficiency of a large scale citizen science monitoring project. RESULTS: We recorded 180 amphibian and 72 reptile road-kills comprising eight species mainly occurring on agricultural roads. KDE+ analyses revealed a significant clustering of road-killed amphibians and reptiles, which is an important information for authorities aiming to mitigate road-kills. Overall, hotspots of amphibian and reptile road-kills were next to the land cover classes arable land, suburban areas and vineyards. Conditional probabilities and GLMs identified road-kills especially next to preferred habitats of green toad, common toad and grass snake, the most often found road-killed species. A citizen science approach appeared to be more cost-efficient than monitoring by professional researchers only when more than 400 km of road are monitored. CONCLUSIONS: Our findings showed that freely available remote sensing data in combination with a citizen science approach would be a cost-efficient method aiming to identify and monitor road-kill hotspots of amphibians and reptiles on a larger scale.

Incidence and clinical course of thrombus formation on atrial septal defect and patient foramen ovale closure devices in 1,000 consecutive patients.

OBJECTIVES: The purpose of this study was to investigate the incidence, morphology, and clinical course of thrombus formation after catheter closure of intra-atrial shunts. BACKGROUND: Post-procedure detailed information about thrombotic material on different devices for transcatheter closure is missing. METHOD: A total of 1,000 consecutive patients were investigated after patent foramen ovale (PFO) (n = 593) or atrial septal defect (ASD) (n = 407) closure. Transesophageal echocardiography (TEE) was scheduled after four weeks and six months. Additional TEEs were performed as clinically indicated. RESULTS: Thrombus formation in the left atrium (n = 11), right atrium (n = 6), or both (n = 3) was found in 5 of the 407 (1.2%) ASD patients and in 15 of the 593 (2.5%) PFO patients (p = NS). The thrombus was diagnosed in 14 of 20 patients after four weeks and in 6 of 20 patients later on. The incidence was: 7.1% in the CardioSEAL device (NMT Medical, Boston, Massachusetts); 5.7% in the StarFLEX device (NMT Medical); 6.6% in the PFO-Star device (Applied Biometrics Inc., Burnsville, Minnesota); 3.6% in the ASDOS device (Dr. Ing, Osypka Corp., Grenzach-Wyhlen, Germany); 0.8% in the Helex device (W.L. Gore and Associates, Flagstaff, Arizona); and 0% in the Amplatzer device (AGA Medical Corp., Golden Valley, Minnesota). The difference between the Amplatzer device on one hand and the CardioSEAL device, the StarFLEX device, and the PFO-Star device on the other hand was significant (p < 0.05). A pre-thrombotic disorder as a possible cause of the thrombus was found in two PFO patients. Post-procedure atrial fibrillation (n = 4) and persistent atrial septal aneurysm (n = 4) had been found as significant predictors for thrombus formation (p < 0.05). In 17 of the 20 patients, the thrombus resolved under anticoagulation therapy with heparin or warfarin. In three patients, the thrombus was removed surgically. CONCLUSIONS: The incidence of thrombus formation on closure devices is low. The thrombus usually resolves under anticoagulation therapy.

Cardiac perforation following transcatheter PFO closure.

From December 1998 to August 2001, transcatheter closure of patent foramen ovale (PFO) with an Amplatzer PFO occluder has been successfully performed in our center in 102 patients without severe complications. We are reporting the first known case of cardiac perforation by an Amplatzer PFO occluder.