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Background
Left ventricular (LV) trabeculation is highly variable among individuals and is increased in some diseases (e.g., congenital heart disease or cardiomyopathies), but its significance in population-representative individuals is unknown.Objectives
The goal of this study was to determine if excessive LV trabeculation in population-representative individuals is associated with preceding changes in cardiac volumes and function.Methods
For technical reasons, the extent of trabeculation, which is expressed as the ratio of noncompacted to compacted (NC/C) myocardium, was measured on cardiac magnetic resonance (CMR) long-axis cine images in 2,742 participants in the MESA (Multi-Ethnic Study of Atherosclerosis) (mean age 68.7 years; 52.3% women; 56.4% with hypertension; 16.8% with diabetes) at examination 5. These were considered in quintiles of trabeculation extent; the NC/C ratio of quintile 5 was 2.46 to 5.41. We determined the relationship between the maximal NC/C ratio and the preceding change (9.5 years between examinations 1 and 5) in end-systolic volume indexed (ESVi) to body surface area. Secondary analyses assessed the associations between the maximal NC/C ratio and preceding changes in end-diastolic volume indexed (EDVi) to body surface area and the ejection fraction (EF).Results
Over 9.5 years, the ESVi decreased by 1.3 ml/m2, the EDVi decreased by 5.1 ml/m2, and the EF decreased by 0.6% (p < 0.0001). Even in subjects with excessive trabeculation, there were no clinically relevant differences in LV volumes and systolic function changes among the quintiles of trabeculation extent.Conclusions
Greater extent of, and even excessive, LV trabeculation measured in end-diastole in asymptomatic population-representative individuals appeared benign and was not associated with deterioration in LV volumes or function during an almost 10-year period. 相似文献Evidence for bronchoscopic lung volume reduction (BLVR) is based on phase 2 studies and small randomized controlled trials with in- and exclusion criteria defining a therapeutic window and contraindications. Little is known about the applicability in routine clinical practice.
AimWhich percentage of patients with severe emphysema referred to a specialized treatment center for BLVR is ultimately suitable for interventional bronchoscopic treatment? What is the relevance of the different contraindications?
MethodsRetrospective evaluation of emphysema patients referred to Asklepios Fachkliniken Munich-Gauting for BLVR between January 2014 and June 2015.
Results138 patients were referred for evaluation of BLVR. 38 patients (27.5%) underwent BLVR procedures (valves n = 18; coils n = 18; thermal vapor ablation n = 2). 100 patients (72.5%) were deemed not eligible for BLVR based on the following contraindications: 34% emphysema morphology and emphysema-related findings (severe homogeneous emphysema, extensive pleuropulmonary adhesions, postinflammatory scaring with natural volume reduction, giant bullae), 16% active smoking; 9% pulmonary function not within indication range; 8% unexpected CT findings (nodules, cancer, interstitial disease); 8% chronic ventilatory failure; 8% patient refused BLVR; 5% relevant comorbidity; 5% frequent exacerbations, 3% preserved quality of life, 4% other.
ConclusionBLVR is a therapeutic option for highly selected patients. In our cohort, one in four could be treated. These data highlight the limitations of BLVR under real-life conditions.
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