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The goal of vascular access creation is to achieve a functioning arteriovenous fistula (AVF) or arteriovenous graft (AVG). An autologous fistula has been shown to be superior to AVG or to central venous catheters (CVCs) with lowest rate of re-intervention, but vessel obstruction or immaturity accounts for 20 % to 54% of cases with primary failure of AVF. This review is focused on the factors influencing maturation; indication and timing of preoperative mapping/creation of vascular access; ultrasound parameters for creation AVF/AVG; early postoperative complications following creation of a vascular access; ultrasound determinants of fistula maturation and endovascular intervention in vascular access with maturation failure. However, vascular accesses that fail to develop, have a high incidence of correctable abnormalities, and these need to be promptly recognized by ultrasonography and managed effectively if a high success rate is to be expected. We review approaches to promoting fistula maturation and duplex ultrasonography (DUS) of evaluating vascular access maturation.

The author of this article gives a personal account of his experience as a Czechoslovak student leader. He reminisces the day when he was invited to address the U.S. Student Association in Kansas City, Missouri. He spoke primarily about the aims and motivations of his generation, the first postwar generation raised and educated under a Communist regime. He blames the previous generation for their frightened silence during Joseph Stalin's atrocities during the 1950s, when innocent people were executed or sent to labor camps. Though, he distrusted the Communist Party, but had a hope that at least its reformist wing might respond to pressure from outside and inside the party.

Prague's Kamikaze Icebreakers Nineteen years ago, in August 1968, in the last daysof the Prague Spring, I was invited to address the U.S. Student Association in Kansas City, Missouri. As [...]

Stenosis is the most frequent vascular access complication and is responsible for access thrombosis and thus long-term patency limitation. Regular arteriovenous graft (AVG) examination by ultrasonography and preemptive balloon angioplasty prolong AVG cumulative patency according to some, but by far not all trials. This was why the routine use of ultrasound surveillance is not recommended recently.In this review we show huge differences in the definition of stenosis significance among the trials and other probable factors, which may have caused the contradiction of the results. Without precise definition of stenosis significance, many AVGs have been undergoing unnecessary balloon interventions with high morbidity, high cost and low benefit.

Purpose Patency of mature vascular access for hemodialysis is mostly limited by the growing stenoses leading to acute access thrombosis. The therapy of choice is usually percutaneous balloon angioplasty (PTA). However, PTA injures the vessel wall and subsequent re-stenosis develops faster than de novo stenosis. Therefore, the key is in appropriate timing of PTA procedures – as late as possible but before access thrombosis develops. Ultrasonography combines the morphologic and functional access assessment, but the former is less precise than angiography. The aim of this study was to compare ultrasonographic and angiographic measuring of residual diameter as the additional criterion of significant stenoses used in our center.Methods Residual diameter of significant stenoses was measured by B-mode ultrasonography three times in 20 patients. All the patients were indicated for angiography and the residual diameter of the stenoses was re-analyzed by this method. The repeatability of ultrasonographic residual diameter measurements and reproducibility in comparison to angiography were expressed by coefficients of variation (CV).Results The residual diameter was 1.69 ± 0.05 mm by ultrasound and 1.65 ± 0.59 mm measured by angiography. In the ultrasound repeatability study, CV was 3.17 ± 2.76% and in the reproducibility study CV was 18.0 ± 15.6%. All the stenoses found to be significant by ultrasound were above 65% by angiography and PTA was performed.Conclusions Ultrasonographic measurement of the residual diameter is stable in experienced hands and is well comparable to angiography results. These findings advocate residual diameter of 2.0 mm as the strong additional criterion of the significant stenoses, which can also be used in ultrasound surveillance of arteriovenous grafts.

Objectives This study aimed to retrospectively assess using computed tomography pulmonary angiography (CTPA) for predicting residual pulmonary hypertension (RPH) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) after pulmonary endarterectomy (PEA).Methods We retrospectively analyzed data of 131 patients with CTEPH who underwent PEA in our center (2008–2015). We measured several diameters of the pulmonary artery and thoracic aorta preoperatively. We evaluated the relationship between these measurements (and their indices) and signs of RPH represented by pulmonary artery systolic pressure (PASP) estimated by echocardiography.Results Significant correlations were observed between the aortopulmonary index and prediction of any residual hypertension and moderate/severe hypertension 1 year after PEA, and any residual hypertension and severe hypertension 2 years after PEA. The aortopulmonary index was significantly related to a reduction in PASP 1 year after the operation. A lower aortopulmonary index (≤0.88 for the ascending aorta and ≤0.64 for the descending aorta) predicted lower RPH.Conclusions Preoperative CTPA parameters can be used to assess the risk of RPH after PEA. The aortopulmonary index has significant predictive value for RPH and a reduction in PASP after PEA. Lower values of the aortopulmonary index suggest a better outcome after PEA.

Several letters to the editor are presented in response to articles in the previous issues including "The Library in the New Age," by Robert Darnton in the June 2008 issue, another about an essay of Zadie Smith on Franz Kafka in the July 17, 2008 issue, and a review of David Attenborough's Life in Cold Blood in the May 1, 2008 issue.