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Subject: search.filters.subject.pulsatility index

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    Effect of Aortic Valve Opening Pattern on Endothelial Function After Continuous-Flow Left Ventricular Assist Device Implantation
    (2023) Kaya, Ersin; Kocabas, Umut; Simsek, Evrim; Nalbantgil, Sanem; Engin, Cagatay; Ozbaran, Mustafa; Akilli, Azem; 0000-0001-6424-9399; 37773149; GXG-7709-2022
    This study aimed to evaluate the effects of aortic valve opening patterns on endothelial functions in patients undergoing continuous-flow left ventricular assist device (CF-LVAD) implantation. This study included 43 patients who underwent CF-LVAD implantation and 35 patients with heart failure reduced ejection fraction (HFrEF; control group). The CF-LVAD group was divided into three subgroups based on aortic valve opening patterns: open with each beat, intermittently opening, and not opening groups. Flow-mediated dilatation (FMD) and pulsatility index (PI) were compared before and 3 months after CF-LVAD implantation. Cardiopulmonary exercise test (CPET) and 6 minute walk test (6-MWT) scores were measured at baseline and follow-up in the CF-LVAD group. The mean FMD and PI of patients in the CF-LVAD group reduced 3 months after implantation. Patients with intermittently opening and not opening aortic valves had worse endothelial function at follow-up. Before and 3 months after implantation FMD% did not significantly differ in patients whose aortic valves were open with each beat (4.72 +/- 1.06% vs. 4.67 +/- 1.16%, p = 0.135). Pulsatility index changes paralleled FMD changes. Cardiopulmonary exercise test and 6-MWT scores improved after implantation but without significant differences between subgroups. Maintaining normal aortic valve function after CF-LVAD implantation may reduce endothelial dysfunction; however, larger studies are needed for long-term clinical effects.
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    Effects of Continuous-Flow Left Ventricular Assist Device Therapy on Peripheral Vascular Function
    (2022) Kaya, Ersin; Kocabas, Umut; Simsek, Evrim; Nalbantgil, Sanem; Kahraman, Umit; Engin, Cagatay; Yagdi, Tahir; Ozbaran, Mustafa; Akilli, Azem; 35089263; GXG-7709-2022
    The peripheral vascular effects of continuous-flow left ventricular assist device (CF-LVAD) implantation are still unclear. The aim of the current study was to determine peripheral vascular function before and after implantation of CF-LVAD in patients with end-stage heart failure (HF), and to compare this data to age- and sex-matched chronic heart failure with reduced ejection fraction (HFrEF) patients. Forty-three consecutive end-stage HF patients (New York Heart Association [NYHA] class III/IV; three women and 40 men; mean age 53 +/- 11 years) who planned to receive CF-LVAD implantation comprised the LVAD patient population, and their clinical characteristics, preoperative and third postoperative month peripheral vascular function assessment data including flow-mediated dilation (FMD) and pulsatility index (PI) assessed by ultrasound Doppler in brachial artery were compared to age- and sex-matched chronic, stable HFrEF patients (NYHA class II; five women and 30 men; mean age 51 +/- 10 years). After CF-LVAD implantation, median FMD decreased from 5.4 to 3.7% (p < 0.001), and median PI decreased from 6.9 to 1.4 (p < 0.001). In patients with end-stage HF before CF-LVAD implantation, FMD and PI were significantly lower compared to the chronic HFrEF patients (FMD: 5.4% +/- 0.9% vs. 7.6% +/- 1.1%; p < 0.001, respectively) and (PI: 6.9 +/- 1.3 vs. 7.4 +/- 1.2; p = 0.023, respectively). The current study revealed impaired peripheral vascular function in the end-stage HF patients compared to stable HFrEF patients, and documented the deterioration of peripheral vascular function after CF-LVAD implantation. These results suggest that impaired peripheral vascular function in the CF-LVAD patients compared to preoperative assessment is a consequence of the nonpulsatile blood flow due to the continuous-flow mechanical support.
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    Reference values of the ductus venosus pulsatility index for pregnant women between 11 and 13(+6) weeks of gestation
    (2020) Kalayci, Hakan; Baran, Safak Yilmaz; Durdag, Gulsen Dogan; Yetkinel, Selcuk; Alemdaroglu, Songul; Ozdogan, Serdinc; Simsek, Seda Yuksel; Kilicdag, Esra Bulgan; 0000-0002-0942-9108; 0000-0003-4335-6659; 0000-0002-5064-5267; 0000-0002-2165-9168; 0000-0001-5874-7324; 0000-0002-1767-1527; 30157671; AAK-8872-2021; AAK-7016-2021; AAI-8400-2021; ABF-6439-2020; AAI-9594-2021; AAL-1530-2021
    Purpose: The ductus venosus pulsatility index velocity (DV PIV) has become a popular ultrasonographic measurement during the first trimester of pregnancy. The value of the DV PIV has been the topic of ongoing discussion in the literature, and its reference value in the normal population has not yet been established. Therefore, we aimed to determine a reference value for the DV PIV. Materials and Methods: We retrospectively evaluated our records of first-trimester ultrasonography performed between 2016 and 2017. Our inclusion criteria were as follows: singleton pregnancy; crown-rump length (CRL) between 45 and 84 mm; absence of structural abnormalities on the ultrasound examination; and absence of chromosomal abnormalities. Records of 820 patients were evaluated. According to the inclusion criteria, records of 458 patients were included in this study. All ultrasound examinations were performed by a single operator with the Voluson E8 (5- to 8-MHz 3 D transducer; General Electric Healthcare, Little Chalfont, UK) via the transabdominal route. Gestational weeks were designated according to CRL measurements at the beginning of the examination. Nuchal translucency (NT), nasal bone visualization (NB), tricuspid valve regurgitation (TR), "a"-wave pattern, DV PIV, S-wave (peak systolic velocity), D-wave (peak diastolic velocity), a-wave (atrial contraction in late diastole), and time-averaged maximum velocity (TAMXV) measurements were performed. To evaluate the DV Doppler images, a mid-sagittal view of the fetal profile was obtained. Color Doppler and pulse Doppler gate were used in the distal portion of the umbilical sinus, and at least three typical DV waveforms were detected. The SPSS 21.0 statistical program (IBM, Armonk, NY) was used to analyze variables. Results: The mean age, body mass index, CRL, gestational age, and NT values were 30.3 years (range, 18-45), 23.9 kg/m(2) (range, 15.5-46.6), 59.5 mm (range, 45-79), 12.3 weeks (range, 11.2-13.6), and 1.58 mm (range, 0.73-2.62), respectively. The median gravidity and parity were 2 (1-8) and 0 (0-4), respectively. The "a"-wave pattern was identified in all cases, but TR was not detected in any of the cases. Measurements of DV PIV with a Gaussian distribution were suitable according to the Shapiro-Wilk test (p = .252). The mean DV PIV was 0.98, and the fifth and 95th percentiles were 0.73 and 1.22 (+/- 2 SD), respectively. A statistical analysis of our cohort revealed that DV PIV values less than 0.73 and more than 1.22 were beyond the normal range. The mean S-wave, D-wave, a-wave, and TAMXV values were 31.18, 25.64, 8.68, and 22.72 cm/s, respectively. Conclusions: The value of DV PIV measurements is debated in the literature. Using our cohort, we defined the means and ranges of DV PIV. Determining the normal ranges of DV PIV could be helpful to anticipate congenital or chromosomal abnormalities. Further studies are needed to demonstrate the clinical importance of DV PIV, especially for patients with abnormal DV PIV measurements.