Browsing by Author "Boyd, Jack H."

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    Epicardial adipose excision slows the progression of porcine coronary atherosclerosis
    (Springer Nature, 2014-01-03) McKenney, Mikaela L.; Schultz, Kyle A.; Boyd, Jack H.; Byrd, James P.; Alloosh, Mouhamad; Teague, Shawn D.; Arce-Esquivel, Arturo A.; Fain, John N.; Laughlin, M. Harold; Sacks, Harold S.; Sturek, Michael; Cellular and Integrative Physiology, School of Medicine
    Background: In humans there is a positive association between epicardial adipose tissue (EAT) volume and coronary atherosclerosis (CAD) burden. We tested the hypothesis that EAT contributes locally to CAD in a pig model. Methods: Ossabaw miniature swine (n=9) were fed an atherogenic diet for 6 months to produce CAD. A 15 mm length by 3-5 mm width coronary EAT (cEAT) resection was performed over the middle segment of the left anterior descending artery (LAD) 15 mm distal to the left main bifurcation. Pigs recovered for 3 months on atherogenic diet. Intravascular ultrasound (IVUS) was performed in the LAD to quantify atheroma immediately after adipectomy and was repeated after recovery before sacrifice. Coronary wall biopsies were stained immunohistochemically for atherosclerosis markers and cytokines and cEAT was assayed for atherosclerosis-related genes by RT-PCR. Total EAT volume was measured by non-contrast CT before each IVUS. Results: Circumferential plaque length increased (p<0.05) in the proximal and distal LAD segments from baseline until sacrifice whereas plaque length in the middle LAD segment underneath the adipectomy site did not increase. T-cadherin, scavenger receptor A and adiponectin were reduced in the intramural middle LAD. Relative to control pigs without CAD, 11β-hydroxysteroid dehydrogenase (11βHSD-1), CCL19, CCL21, prostaglandin D2 synthase, gp91phox [NADPH oxidase], VEGF, VEGFGR1, and angiotensinogen mRNAs were up-regulated in cEAT. EAT volume increased over 3 months. Conclusion: In pigs used as their own controls, resection of cEAT decreased the progression of CAD, suggesting that cEAT may exacerbate coronary atherosclerosis.
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    Human aortic allograft: an excellent conduit choice for superior vena cava reconstruction
    (Springer Nature, 2014-01-15) Spera, Kristyn; Kesler, Kenneth A.; Syed, Amjadullah; Boyd, Jack H.; Surgery, School of Medicine
    Superior vena cava (SVC) reconstruction is occasionally required in the treatment of benign and malignant conditions. We report a patient with symptomatic SVC obstruction secondary to mediastinal fibrosis successfully reconstructed with an aortic allograft.
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    Ventricular assist device implantation in the elderly
    (AME Publishing Company, 2014-11) Hiesinger, William; Boyd, Jack H.; Woo, Y. Joseph; Department of Surgery, IU School of Medicine
    BACKGROUND: Dramatic advances in ventricular assist device (VAD) design and patient management have made mechanical circulatory support an attractive therapeutic option for the growing pool of elderly heart failure patients. METHODS: A literature review of all relevant studies was performed. No time or language restrictions were imposed, and references of the selected studies were checked for additional relevant citations. RESULTS: In concordance with the universal trend in mechanical circulatory support, continuous flow devices appear to have particular benefits in the elderly. In addition, the literature suggests that early intervention before the development of cardiogenic shock, important in all patients, is particularly paramount in older patients. CONCLUSIONS: The ongoing refinement of patient selection, surgical technique, and post-operative care will continue to improve surgical outcomes, and absolute age may become a less pivotal criterion for mechanical circulatory support. However, clear guidelines for the use of mechanical circulatory support in the elderly remain undefined.