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Carotid Endarterectomy in the Very Elderly: Short-, Medium-, and Long-Term Outcomes
Shabin Fahad,Sayali Shirsath,Matthew Metcalfe,Ahmed Elmallah 대한혈관외과학회 2023 Vascular Specialist International Vol.39 No.3
Purpose: Carotid endarterectomy (CEA) has an established effect on stroke-free survival in patients with carotid artery stenosis. Most landmark trials excluded patients ≥80 years of age due to their perceived high risk and uncertainty regarding the benefits of CEA. Despite the ongoing global increase in life expectancy, guidelines have not changed. The current study aimed to assess CEA outcomes in patients ≥80 years of age. Materials and Methods: Data from patients ≥80 years of age, who underwent CEA between April 2016 and April 2022, were collected. Demographic information, comorbidities, surgical details, operative details, outcomes, and post-CEA survival were reviewed, and long-term data up to April 2023 were collected. Results: Over the 6-year study period, 258 CEA procedures were recorded, of which 70 (27.1%) were performed in patients ≥80 years of age; the mean age was 84 years (range, 80-96 years), 47 (67.1%) were males, and 69 (98.6%) were symptomatic. Twenty-three (32.9%) patients were American Society of Anesthesiologists (ASA) grade 2, and 47 (67.1%) were grade 3. The 30-day stroke and mortality rates were 4.3% and 1.4%, respectively. At 1, 3, and 5 years, the cumulative freedom-from-stroke rates were 95.7%, 92.9%, and 91.4%, respectively, and the cumulative survival rates were 94.3%, 75.7%, and 61.4%, respectively. No risk factors affected early or late stroke or early mortality rates. Patients with ASA grade 3 had significantly lower cumulative survival than those with grade 2 (HR, 5.29; 95% CI, 1.590-17.603; P<0.01). Conclusion: CEA was safe and effective in average-risk, elderly patients. Higher risk patients (i.e., ASA 3) showed no increased 30-day risk for stroke or mortality but exhibited significantly worse long-term survival. Hence, careful consideration of the benefits before performing CEA is crucial.
A. T. Raghavender,Sagar E. Shirsath,D. Pajic,K. Zadro,T. Milekovic,K. M. Jadhav,K. Vijaya Kumar 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.61 No.4
Nanocrystalline CuFe<sub>2-x</sub>Al<sub>x</sub>O<sub>4</sub> (0.0 ≤ x ≤ 1.0) was synthesized by sol-gel method and their structural and magnetic properties were investigated. The crystallite size was observed to decrease from 20 to 6 nm with increasing Al content. The lattice parameters were observed to decrease with increasing Al content. The cation distribution from X-ray intensity calculations revealed that Cu<sup>2+</sup> preferably occupy octahedral [B] sites. Al<sup>3+</sup> ions replace the Fe<sup>3+</sup> ions in the tetrahedral (A) and octahedral [B] sites. As a result the Fe<sup>3+</sup> concentration at (A) and [B] sites decreases leading to the suppression of long range magnetic ordering. Magnetic hysteresis loops were measured at room temperature with a maximum applied magnetic field of ≒1 T. As Al<sup>3+</sup> content increases, the measured magnetic hysteresis curves become more and more narrow and the saturation magnetization and remanent magnetization both decreased. The reduction of magnetization with increase of aluminum content is caused by non-magnetic Al<sup>3+</sup> ions and weakened interaction between sub-lattices. The reduction of magnetization compared to bulk may originate from the smallness of particles. This is accompanied also with coercive field reduction.
Study of structural, electrical and magnetic properties of Cr doped Ni–Mg ferrite nanoparticle
Hashim, M.,Meena, S. S.,Kotnala, R. K.,Shirsath, S. E.,Roy, A. S.,Parveen, A.,Bhatt, P.,Kumar, S.,Jotania, R. B.,Kumar, R. Elsevier Science B.V., Amsterdam. 2014 Journal of Alloys and Compounds Vol.602 No.-