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There are limited data on the effect of bioprosthetic valve remodeling (BVR) on transcatheter heart valve (THV) expansion and function following valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR) in a nonfracturable surgical heart valve (SHV). This study sought to assess the impact of BVR of nonfracturable SHVs on THVs after VIV implantation. VIV TAVR was performed using 23-mm SAPIEN3 (S3, Edwards Lifesciences) or 23/26-mm Evolut Pro (Medtronic) THVs implanted in 21/23-mm Trifecta (Abbott Structural Heart) and 21/23-mm Hancock (Medtronic) SHVs with BVR performed with a noncompliant TRUE balloon (Bard Peripheral Vascular Inc). Hydrodynamic assessment was performed, and multimodality imaging including micro–computed tomography was performed before and after BVR to assess THV and SHV expansion. BVR resulted in limited improvement of THV expansion. The largest gain in expansion was observed for the S3 in the 21-mm Trifecta with up to a 12.7% increase in expansion at the outflow of the valve. Minimal change was observed at the level of the sewing ring. The Hancock was less amenable to BVR with lower final expansion dimensions than the Trifecta. BVR also resulted in notable surgical post flaring of up to 17.6°, which was generally more marked with the S3 than with the Evolut Pro. Finally, BVR resulted in very limited improvement in hydrodynamic function. Severe pinwheeling was observed with the S3, which improved slightly but persisted despite BVR. When performing VIV TAVR inside a Trifecta and Hancock SHV, BVR had a limited impact on THV expansion and resulted in SHV post flaring with unknown consequences on coronary obstruction risk and long-term THV function. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of rh immune globulin (RhIG) for the prevention of Rhesus D (RhD) alloimmunization has significantly decreased the incidence of RhD alloimmunization. Despite long-standing prevention, the experiences of RhD negative women with pregnancy is absent in the literature. The purpose of this study was to explore the experiences of RhD negative women with pregnancy. Utilizing an Interpretive Description approach, semi-structured interviews were conducted with RhD negative women about their pregnancies. This study took place within the geographic context of northern British Columbia (BC). The analysis involved a two-cycle approach to identify themes within the data. Sixteen RhD negative women that live in northern BC participated in this study. The analysis identified that RhD negative women are uninformed and want to be involved in the decision-making process regarding the prevention of RhD alloimmunization. The themes that emerged from the interview data were communication, information-seeking behaviour, out of sight out of mind, choice and trust, and patient advocacy. The participants in this study described lacking information regarding the prevention of RhD alloimmunization. They sought information to overcome the gaps in knowledge and a desire to be involved in the decision-making process. RhD negative women want information and to be involved in the decision-making process in the prevention of RhD alloimmunization. Working with RhD negative women to develop decision-aids and/or other educational tools to aid in the decision-making process are warranted. [ABSTRACT FROM AUTHOR]

Abstract Objectives This study investigated processes causing leaflet thickening and structural valve degeneration (SVD). Background Although transcatheter aortic valve replacement (TAVR) has changed the treatment of aortic stenosis, concerns remain regarding SVD, potentially related to valve thrombosis and thickening, based on studies using computed tomography (CT). Detailed histological analyses are provided to help attain insights into these processes. Methods Explanted transcatheter heart valves (THVs) were evaluated for thrombosis, fibrosis, and calcification for quantification of leaflet thickness. Immunohistochemical and microscopy approaches were used to investigate SVD-associated mechanisms. Results THVs (n = 23) were obtained from 22 patients (median 81 years of age; 50% male) from 0 to 2,583 days post TAVR. Maximal leaflet thickness increased relative to implant duration (ρ = 0.427; p = 0.027). THVs explanted after >2 years were thicker than those explanted after <2 years (p = 0.007). All THVs had adherent thrombus on both aortic and ventricular sides, which beyond 60 days was seen in combination with fibrosis and beyond 4 years had calcification. Early thrombus formation (<60 days) occurred despite rapid endothelialization with an abnormal hyperplastic phenotype. Fibrosis was observed in 6 patients on both the aortic and the ventricular THV surfaces, remodeled over time, and was associated with matrix metalloproteinase-1 expression. Five THVs showed overt calcification associated with adherent thrombus and fibrosis. Conclusions There is a time-dependent degeneration of THVs consisting of thrombus formation, endothelial hyperplasia, fibrosis, tissue remodeling, proteinase expression, and calcification. Future investigation is needed to further understand these mechanisms contributing to leaflet thickening and SVD. Graphical abstract [ABSTRACT FROM AUTHOR]

Abstract Introduction Angina, myocardial ischemia, and coronary artery physiology in hypertrophic cardiomyopathy (HCM) are poorly understood. However, coronary computed tomography angiography (CCTA) with fractional flow reserve from CT (FFR CT) analysis offers a non-invasive method for evaluation of coronary artery volume to myocardial mass ratio (V/M) that may provide insight into such mechanisms. Thus, we sought to investigate changes in V/M in HCM. Methods A retrospective analysis was performed on 37 HCM patients and 37 controls matched for age, sex, and cardiovascular risk factors; CCTA-derived coronary artery lumen volume (V) and myocardial mass (M) were used to determine V/M. FFR CT values were calculated for the left anterior descending (LAD), left circumflex (LCx) and right coronary (RCA) arteries as well as the 3-vessel cumulative FFR CT values. Results HCM patients had significantly increased myocardial mass (176 ± 84 vs. 119 ± 27 g, p < 0.0001) and total coronary artery luminal volume (4112 ± 1139 vs. 3290 ± 924 mm3, p < 0.0001) that resulted from increases in segmented luminal volumes of both the left and right coronary artery systems. However, HCM patients had significantly decreased V/M (23.8 ± 5.9 vs. 26.5 ± 5.3 mm3/g; p = 0.026) which was further decreased when restricting V/M analysis to those HCM patients with septal hypertrophy (22.4 mm3/g, p = 0.01) that was mild-moderately predictive of HCM (AUC = 0.68). HCM patients also showed significantly lower nadir FFR CT values in the LCx (0.87 ± 0.06 vs. 0.91 ± 0.06, p = 0.02), and cumulative 3-vessel FFR CT values (2.58 ± 0.18 vs. 2.63 ± 0.14, p = 0.006). Conclusions HCM patients demonstrate significantly greater coronary volume. Despite this, HCM patients suffer from decreased V/M. Further prospective studies evaluating the relationship between V/M, angina, and heart failure in HCM are needed. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: Based on their association with malignant proliferation, using noninvasive phosphorus MR spectroscopic imaging (31P MRSI), we measured the tumor content of the phospholipid-related phosphomonoesters (PME), phosphoethanolamine and phospholcholine, and its correlation with treatment outcome in newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL) receiving standard first-line chemotherapy. Experimental Design: The PME value normalized to nucleoside triphosphates (PME/NTP) was measured using 31P MRSI in tumor masses of 20 patients with DLBCL before receiving standard first-line chemotherapy. Response at 6 months was complete in 13 patients and partial in seven. Time to treatment failure (TTF) was ≤11 months in eight patients, from 18 to 30 months in three, and ≥60 months in nine. Results: On a t test, the pretreatment tumor PME/NTP mean value (SD, n) of patients with a complete response at 6 months was 1.42 (0.41, 13), which was significantly different from the value of 2.46 (0.40, 7) in patients with partial response (P < .00001). A Fisher test significantly correlated the PME/NTP values with response at 6 months (sensitivity and specificity at 0.85, P < .004) while a Cox proportional hazards regression significantly correlated the PME/NTP values with TTF (hazard ratio = 5.21, P < .02). A Kaplan–Meier test set apart a group entirely composed of patients with TTF ≤ 11 months (hazard ratio = 8.66, P < .00001). Conclusions: The pretreatment tumor PME/NTP values correlated with response to treatment at 6 months and time to treatment failure in newly diagnosed patients with DLBCL treated with first-line chemotherapy, and therefore they could be used to predict treatment outcome in these patients. [Copyright &y& Elsevier]

This paper introduces a special issue of Habitat International on land tenure and property rights. It sets the scene for case studies carried out in countries around the world commissioned by the author as part of a research project11‘Progress in the provision of secure tenure for the urban poor’ a research project undertaken by Geoffrey Payne and Associates and an international team of researchers between 2002 and 2003 with funding from the UK Department for International Development (DFID). The views expressed in this issue are not necessarily those of the DFID. updating previous research on innovative approaches to tenure for the urban poor in 16 countries. The research reviewed changes in the selected tenure systems and placed them in a wider context of local land and housing markets.A key feature of the paper is a typological framework which enables policy makers or others to identify the range and distribution of statutory, customary and informal tenure categories in a city, the de facto levels of security provided by each and the various property rights associated with them. The paper demonstrates that tenure systems form a continuum of categories and that policies need to recognise crucial distinctions between these if policy objectives are to be achieved. The role of tenure policy in facilitating or inhibiting security and rights for vulnerable groups, such as tenants and women is discussed and proposals made for implementing a pro-poor tenure policy. The paper concludes by introducing the case study papers. [Copyright &y& Elsevier]

In its effort to fight poverty, the Royal Government of Cambodia has emphasised the importance of providing land titles to its population. This aim has been widely supported both financially and technically by the World Bank and German Technical Assistance (GTZ) as well as foreign governments such as Finland. The World Bank''s Regional Land Policy Workshop in Asia held in Phnom Penh in April 200211Minister''s speech, April 2002. sought to kick off the process of a country-wide land titling programme which also covers Phnom Penh city.Even though this heavily budgeted project looks set to produce more than a million22The total target of land titles to be issued is varied from one executive year to another, i.e., 12,000 in 2002, 102,000 in 2003, 192,000 in 2004, 300,000 in 2005, 330,000 in 2006, and only 66,000 in 2007 (The World Bank, 2002, p. 43). land titles within approximately 5 years, it will face many difficulties and challenges related to land tenure due to overlapping claims and border demarcation disputes.This paper addresses the types of land tenure existing in Phnom Penh which will present problems to the land titling programme and suggests that an alternative approach may be preferable. It is based on a field survey of households in a range of informal and formal low-income settlements of 10 areas in Phnom Penh, Cambodia. It also involved interviews with a number of key stakeholders in government agencies, the private sector, NGOs and representatives of international agencies. A total of 700 householders were interviewed and an additional 70 informal case studies were completed to obtain qualitative information to complement the quantitative data obtained through the survey. [Copyright &y& Elsevier]

This brief review considers to what extent Magnetic Resonance Spectroscopy (MRS) can play a role in monitoring early tumour response with examples of preclinical studies and selected clinical studies in tumours of children and young adults. An early non-invasive indicator of tumour response to therapy would provide useful information regarding the effectiveness of therapy. This might be a relevant prognostic factor in new patients and in phase II studies could facilitate recommendations at an early stage as to whether to continue treatment. This review suggests that several markers and ratios are emerging as potential prognostic markers, but larger prospective studies are needed before translating this into clinical practice. [Copyright &y& Elsevier]