Bone regeneration and graft material resorption in extraction sockets grafted with bioactive silica-calcium phosphate composite (SCPC) versus non-grafted sockets: clinical, radiographic, and histological findings.

PURPOSE: The purpose of the present study was to evaluate the effect of silica-calcium phosphate composite (SCPC) granules on bone regeneration in extraction sockets. METHODS: Ten patients were selected for a split-model study. In each patient, bone healing in SCPC-grafted and control ungrafted sockets was analyzed through clinical, radiographic, histomorphometric, and immunohistochemical assessments 6 months postoperatively. RESULTS: A radiographic assessment using cone-beam computed tomography showed minimal ridge dimension changes in SCPC-grafted sockets, with 0.39 mm and 1.79 mm decreases in height and width, respectively. Core bone biopsy samples were obtained 6 months post-extraction during implant placement and analyzed. The average percent areas occupied by mature bone, woven bone, and remnant particles in the SCPC-grafted sockets were 41.3%±12%, 20.1%±9.5%, and 5.3%±4.4%, respectively. The percent areas of mature bone and woven bone formed in the control ungrafted sockets at the same time point were 31%±14% and 24.1%±9.4%, respectively. Histochemical and immunohistochemical analyses showed dense mineralized bundles of type I collagen with high osteopontin expression intensity in the grafted sockets. The newly formed bone was well vascularized, with numerous active osteoblasts, Haversian systems, and osteocytes indicating maturation. In contrast, the new bone in the control ungrafted sockets was immature, rich in type III collagen, and had a low osteocyte density. CONCLUSIONS: The resorption of SCPC granules in 6 months was coordinated with better new bone formation than was observed in untreated sockets. SCPC is a resorbable bone graft material that enhances bone formation and maturation through its stimulatory effect on bone cell function. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03897010.

Mechanism and Risk Factors for Death in Adults With Tetralogy of Fallot.

One of the goals of lifelong care in adults with tetralogy of Fallot (TOF) is early identification and treatment of patients at high risk for adverse events. Clinical risk stratification tools are critical for achieving this goal. We reviewed the Mayo Adult Congenital Heart Disease database and identified 465 TOF patients (age 37 ± 14 years, men 223 [48%]) seen at Mayo Clinic Rochester between 1990 and 2017. The aim was to determine the risk factors for death and/or heart transplant through a comprehensive analysis of 8 groups of variables (demographics, co-morbidities, medications, heart rhythm, echocardiography, cardiac magnetic resonance imaging, cardiac catheterization, and cardiopulmonary exercise test data) using univariable and multivariable Cox proportional hazard models. The end point of death and/or transplant occurred in 57 (12%) patients during a follow-up of 13.6 ± 8.2 years, yielding an event rate of 0.9% per year. Independent risk factors were age >42 years, atrial fibrillation, ≥moderate QRS fragmentation, left ventricular ejection fraction <50%, right ventricular end-diastolic pressure >16 mm Hg, and left ventricle end-diastolic pressure >16 mm Hg. There is nearly a twofold increase in the risk of death and/or transplant per unit increase in number of risk factors (hazard ratio 1.92, 95% confidence interval 1.62 to 2.27, p <0.001). In conclusion, the current study provides risk stratification indices based on a comprehensive risk model of all clinical variables in an unselected TOF population. Further studies are required to determine whether interventions targeted at modifying these risk factors will alter the annual event rate.

Coronary artery disease in adults with tetralogy of Fallot.

BACKGROUND: There are limited data about outcomes of coronary artery disease (CAD) in adults with repaired tetralogy of Fallot (TOF). The purpose of this study was to describe the prevalence and treatment of CAD in adults with TOF, and the impact of CAD on long-term survival. METHODS: Retrospective review of MACHD database for adults with repaired TOF who underwent aortic root/selective coronary angiogram, 1990-2017. Patients were categorized into three groups: (1) No CAD defined as normal coronary angiogram; (2) Mild CAD defined as ≤50% stenosis in all vessels; and, (3) Significant CAD defined as >50% stenosis in any vessel. RESULTS: We identified 105 (23%) of 465 TOF patients that had angiograms; mean age 47 ± 12 years. The prevalence of mild CAD and significant CAD was 19% (20 patients) and 15% (16 patients), respectively. Of these 16 patient with significant CAD, 9 (56%), 3 (19%), and 4 (24%) patients received guideline directed medical therapy, percutaneous coronary intervention, and coronary artery bypass grafting, respectively. Significant CAD was an independent risk factor for mortality (HR: 2.03, 95% CI 1.64-4.22, P = .022) after adjustment for differences in age, and prevalence of atrial fibrillation and renal dysfunction. CONCLUSIONS: Based on a review of a selected cohort of 105 TOF patients, the prevalence of mild CAD and significant CAD was 19% and 15%, respectively. Significant CAD was an independent risk factor for mortality. There is need for more research to determine optimal noninvasive diagnostic strategies and optimal patient selections and methods for revascularization.