Ultrasound Guided Compression for Iatrogenic Femoral Artery Pseudo Aneurysms To the Editor: Despite increasing use of radial artery for percutaneous interventions, femoral artery is still commonly used for both diagnostic and therapeutic interventions. Decreased size of sheats is the principal mechanism underlying reduced complication rates for femoral artery interven- tions. The most common accesserelated complications af- ter femoral artery interventions are pseudoaneurysms, hematoma, arteriovenous fistula, and retroperitoneal hemorrhage. Pseudoaneurysms are frequently due to lower punc- ture below the common femoral artery bifurcation. The frequency is reported between 0.2% after diagnostic procedures and nearly 8% after interventional procedures. 1 In our institution, we perform nearly 2,400 diagnostic and interventional procedures using femoral access. In the last 2 years, we experienced 16 cases of femoral pseudoa- neurysms following femoral access. This makes nearly 0.003%. We did not perform routine ultrasonography, and thus, this ratio is not comparable to other studies. What we would like to underscore is 15 out of 16 cases (93.7%) were successfully treated with ultrasound- guided compression and only 1 patient underwent sur- gery who had a 25-mm pseudoaneurysm. Minimal and maximal duration of compression was 15 min and 3 hr, respectively. Before compression, intravenous line was established, skin was sterilized, and topical lidocaine was applied in order to reduce pain. Ultrasound-guided thrombin injection is another alter- native method for treatment of femoral artery pseudoa- neurysms. By using both manual compression and ultrasound-guided thrombin injection, Dzijan-Horn et al. 2 reported a success rate of 97.2%. In their series, only 10 patients out of 432 pseudoaneurysm cases (2.3%) needed surgical intervention. In conclusion, ultrasound-guided compression is still an effective method for the treatment of iatrogenic femoral artery pseudoaneurysms. Gokhan Altunbas 1 Murat Sucu 2 1 Gaziantep University School of Medicine, Gaziantep, Turkey 2 Department of Cardiology, Gaziantep University, Gaziantep, Turkey E-mail: drgokhanaltun@gmail.com REFERENCES 1. Ahmad F, Turner SA, Torrie P, et al. Iatrogenic femoral artery pseudoaneurysmsda review of current methods of diagnostic and treatment. Clin Radiol 2008;63:1310e6. 2. Dzijan-Horn M, Langwieser N, Groha P, et al. Safety and ef- ficacy of a potential treatment algorithm by using manual compression repair and ultrasound-guided thrombin injection for the treatment of iatrogenic femoral artery pseu- doaneurysm in a large patient cohort. Circ Cardiovasc Interv 2014;7:207e15. http://dx.doi.org/10.1016/j.avsg.2018.01.065 Changes in Arterial Stiffness and N-Terminal Pro-Brain Natriuretic Peptide Levels after Endovascular Repair of Descending Thoracic Aorta Dear Editor, We read with great interest a recent article by Moulaka- kis et al. 1 entitled ‘‘Changes in arterial stiffness and N-ter- minal pro-brain natriuretic peptide levels after endovascular repair of descending thoracic aorta.’’ In this prospective study, the authors aimed to investigate changes in arterial stiffness and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in patients undergoing endo- vascular repair of descending thoracic aorta. The authors measured serum levels of NT-proBNP preoperatively, 24 hr, 48 hr, and 6 months postoperatively. In addition, they evaluated pulse wave velocity (PWV) before and 6 months after endovascular repair of descending thoracic aorta. As stated in statistical analysis section and abstract of the article, the authors used 1-way analysis of variance (ANOVA) to assess alteration in PWV (from baseline to 6 months) and NT-proBNP (between 4 phases of measure- ment). Indeed, they evaluated some numerical variables in 1 sample of patients during different time points including baseline, 24 hr, 48 hr, and 6 months after endovascular repair. Since they investigated 1 same sample of patients during different time points (i.e., baseline, 24 hr, 48 hr, and 6 months), their measurements are completely dependent. 2e4 One-way ANOVA is used for comparison of the means of more than 2 independent groups. 5e8 There- fore, after assessment of the normal distribution of studied quantitative variables including NT-proBNP and PWV, the authors must use repeated-measures ANOVA or Friedman test for comparison of the means of each variable at base- line, 24 hr, 48 hr, and 6 months after endovascular repair. 9,10 Furthermore, they must use Wilcoxon test and paired t test for comparison of NT-proBNP and PWV be- tween 2 time points of measurement. Abolfazl Zahedi 1 Milad Ebrahimi 2 1 Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran 2 Department of Immunology, School of Medicine, Shahed University, Tehran, Iran E-mail: milad.labsc@yahoo.com REFERENCES 1. Moulakakis KG, Kadoglou NP, Antonopoulos CN, et al. Changes in arterial stiffness and N-terminal pro-brain Conflict of interest: None. Volume 49, May 2018 Correspondence 321