Clinical and Hemodynamic Outcomes of Balloon-Expandable Mitral Valve-in-Valve Positioning and Asymmetric Deployment: The VIVID Registry

BACKGROUND

Mitral valve-in-valve (ViV) is associated with suboptimal hemodynamics and rare left ventricular outflow tract (LVOT) obstruction.

OBJECTIVES

This study aimed to determine whether device position and asymmetry are associated with these outcomes.

METHODS

Patients undergoing SAPIEN 3 (Edwards Lifesciences) mitral ViV included in the VIVID (Valve-in-Valve International Data) Registry were studied. Clinical endpoints are reported according to Mitral Valve Academic Research Consortium definitions. Residual mitral valve stenosis was defined as mean gradient ≥5 mm Hg. Depth of implantation (percentage of transcatheter heart valve [THV] atrial to the bioprosthesis ring) and asymmetry (ratio of 2 measures of THV height) were evaluated.

RESULTS

A total of 222 patients meeting the criteria for optimal core lab evaluation were studied (age 74 ± 11.6 years; 61.9% female; STS score = 8.3 ± 7.1). Mean asymmetry was 6.2% ± 4.4%. Mean depth of implantation was 19.0% ± 10.3% atrial. Residual stenosis was common (50%; mean gradient 5.0 ± 2.6 mm Hg). LVOT obstruction occurred in 7 cases (3.2%). Implantation depth was not a predictor of residual stenosis (OR: 1.19 [95% CI: 0.92-1.55]; P = 0.184), but more atrial implantation was protective against LVOT obstruction (0.7% vs 7.1%; P = 0.009; per 10% atrial, OR: 0.48 [95% CI: 0.24-0.98]; P = 0.044). Asymmetry was found to be an independent predictor of residual stenosis (per 10% increase, OR: 2.30 [95% CI: 1.10-4.82]; P = 0.027).

CONCLUSIONS

Valve stenosis is common after mitral ViV. Asymmetry was associated with residual stenosis. Depth of implantation on its own was not associated with residual stenosis but was associated with LVOT obstruction. Technical considerations to reduce postdeployment THV asymmetry should be considered.

Gender differences in blue collar workers' use of hearing protection

In this study, the Health Promotion Model (HPM) was used as the basis for a structural equation model of male and female blue collar workers' self-reported use of hearing protection devices (HPDs). Overall use did not differ by gender; in addition, self-efficacy and barriers to use of HPDs were the two best predictors of this behavior for both men and women. Despite the similarities in HPD use and the most important predictors of that use between men and women, the predictive models differed by gender in several ways. Significant predictors of use among men also included age and value of use of HPDs. For women, ethnic status and plant site were additional significant predictors of use. Because the influences of plant site and gender on self-reported use of HPDs could not be separated in this study, further research should address worksite culture and assess differences by gender. Knowledge of these differences will aid development of more effective interventions and may increase the use of hearing protection.

A comparison of multiple indicators--observations, supervisor report, and self-report as measures of workers' hearing protection use

The purpose of this study was to compare multiple indicators of behavior and identify the most viable measure of blue-collar workers' use of hearing protection. Three measures of use were employed: observations, supervisor report, and self-report. Supervisor report was highly discrepant from both self-report and observed use; self-report and observations were highly correlated, and discrepancies between the two were slight. These results suggest that, for this type of measurement, self-report is an appropriate measure and may be the best choice when time and monetary resources restrict measurement to one indicator.

Psychometric testing of the reduced Laffrey Health Conception Scale

PURPOSE

Laffrey's Health Conception Scale (LHCS), an instrument designed to measure personal definitions of health, was reduced with the intent of creating a useful yet less cumbersome version of the LHCS.

DESIGN

The original form of the LHCS was tested in a preliminary study, and results were used as a basis for the reduction of the instrument. The original clinical and new overall wellness subscales were subsequently tested with a larger population of manufacturing plant workers.

SETTING

One chemical plant and three Midwestern manufacturing plants.

SUBJECTS

The sample for the preliminary study comprised 94 chemical plant workers. For the larger study, the sample comprised 892 subjects; because this instrument was part of a larger questionnaire to identify predictors of workers' use of hearing protection, only those workers who spent some part of their work time in areas of the plant which required hearing protection use were eligible to participate.

MEASURES

The original LHCS was used in the preliminary study. The reduced LHCS was used in the larger study and psychometrically evaluated.

RESULTS

The reduced LHCS accounted for 51% of the variance in definition of health; all but one item had loaded on one of the two factors with a loading of .41 or greater. The revised LHCS demonstrated excellent internal consistency. Two distinct factors, the clinical subscale and the overall wellness subscale, were isolated.

CONCLUSIONS

The researchers recommend the reduced LHCS be used for assessing subjects' definition of health; the reduced instrument requires fewer items, and therefore less time, to measure individuals' definitions of health with excellent reliability.

Using incentives to promote workers' participation in worksite research

We designed this study to examine the effects of two types of incentives on the participation rate of workers from two plants in worksite research. There were 186 workers in the study, some of whom received chances for savings bonds. Given reductions in funding and concerns of management, no comparison could be made between the incentives; however, the study provided valuable information regarding planning for incentives in worksite research.

Preparation of 13C and 15N labelled RNAs for heteronuclear multi-dimensional NMR studies

A procedure is described for the efficient preparation of isotopically enriched RNAs of defined sequence. Uniformly labelled nucleotide 5'triphosphates (NTPs) were prepared from E.coli grown on 13C and/or 15N isotopically enriched media. These procedures routinely yield 180 mumoles of labelled NTPs per gram of 13C enriched glucose. The labelled NTPs were then used to synthesize RNA oligomers by in vitro transcription. Several 13C and/or 15N labelled RNAs have been synthesized for the sequence r(GGCGCUUGCGUC). Under conditions of high salt or low salt, this RNA forms either a symmetrical duplex with two U.U base pairs or a hairpin containing a CUUG loop respectively. These procedures were used to synthesize uniformly labelled RNAs and a RNA labelled only on the G and C residues. The ability to generate milligram quantities of isotopically labelled RNAs allows application of multi-dimensional heteronuclear magnetic resonance experiments that enormously simplify the resonance assignment and solution structure determination of RNAs. Examples of several such heteronuclear NMR experiments are shown.