Cardiac resynchronization significantly improved LV function and reversed LV remodeling during long-term follow-up. Patients likely to benefit from CRT can be identified by TDI before implantation of a biventricular pacemaker.
Background-New insight into the 3D dynamic behavior of the mitral valve has prompted a reevaluation of annuloplasty ring designs. Force balance analysis indicates correlation between annulus forces and stresses in leaflets and chords. Improving this stress distribution can intuitively enhance the durability of mitral valve repair. We tested the hypothesis that saddle-shaped annuloplasty rings have superior uniform systolic force distribution compared with a nonuniform force distribution in flat annuloplasty rings. Methods and Results-Sixteen 80-kg pigs had a flat (nϭ8) or saddle-shaped (nϭ8) mitral annuloplasty ring implanted. Mitral annulus 3D dynamic geometry was obtained with sonomicrometry before ring insertion. Strain gauges mounted on dedicated D-shaped rigid flat and saddle-shaped annuloplasty rings provided the intraoperative force distribution perpendicular to the annular plane. Average systolic annular height to commissural width ratio before ring implantation was 14.0%Ϯ1.6%. After flat and saddle shaped ring implantation, the annulus was fixed in the diastolic (9.0%Ϯ1.0%) and systolic (14.3%Ϯ1.3%) configuration, respectively (PϽ0.01). Force accumulation was seen from the anterior (0.72NϮ0.14N) and commissural annular segments (average 1.38NϮ0.27N) of the flat rings. In these segments, the difference between the 2 types of rings was statistically significant (PϽ0.05). The saddle-shaped annuloplasty rings did not experience forces statistically significantly larger than zero in any annular segments. Conclusions-Saddle-shaped annuloplasty rings provide superior uniform annular force distribution compared to flat rings and appear to represent a configuration that minimizes out-of-plane forces that could potentially be transmitted to leaflets and chords.
Objectives The mitral valve annulus naturally conforms to a saddle shape in systole. This configuration is believed to put the leaflets into a lower-energy equilibrium with the annulus and subvalvular apparatus. Conventional flat annuloplasty rings restrict posterior leaflet motion, which may result in a “monocusp” valve, affecting valvular stress distribution. It is hypothesized that saddle-shaped annuloplasty rings cause less distortion of the physiologic leaflet geometry than do flat rings. Methods Twelve pigs were studied in an acute setting with 3-dimensional echocardiography and sonomicrometry before and after implantation of rigid flat (n = 5) and saddle-shaped (n = 7) annuloplasty rings. The rings were true sized to the annulus with equal anterior–posterior and commissure–commissure circumferential dimensions. The saddle-shaped rings had an annular height to commissural width ratio of 15%. Results Saddle-shaped rings maintained both leaflets operational (P <.01). Flat rings made the posterior leaflet immobile and the anterior leaflet aligned flat along the annulus in systole, effectively resulting in monoleaflet function. The average distance from the papillary muscle tips to the posterior annulus decreased by 2.4 ± 0.4 mm after flat ring implantation (P <.01). Conclusions Saddle-shaped annuloplasty rings provide better leaflet coaptation geometry than do flat rings by not hoisting the papillary muscles toward the posterior annulus through the commissural chordae, allowing greater leaflet mobility. This entails a potentially beneficial impact on valvular stress distribution that could affect durability of the repaired valve.
Although initially effective at reducing moderate FIMR, the addition of a ring did not change the clinical course after CABG surgery. At 12 months, no echocardiographic difference was found in terms of residual mitral regurgitation, left ventricular dimensions and function, or clinical outcomes.
Overall, the chordal insertion site had little influence on the tension in the artificial neochordae compared with the interindividual variation. However, abnormal tension fluctuations in the transapically fixated neochordae might predispose to leaflet tears and early repair failure.
Chronic obstructive pulmonary disease (COPD) is one of the leading causes of disability and death in the world. Many people with disease are undiagnosed or untreated due to lack of consensus about the definition of COPD. The objective was to estimate the prevalence of COPD in the Danish population aged 45-84 years and to identify the proportion of persons not receiving appropriate medical treatment. A population-based study in the two Danish counties (population aged 45-84 years = 299,000 persons) based on data from 155 general practices in the 2004-2006 period. Stratified sampling was used to select 4,757 subjects from the Danish Civil Registration System and the National Health Service databases. The diagnosis of COPD was defined as FEV(1)/FVC < 0.70 after bronchodilator. The classification of disease severity was based on criteria developed by the Global Initiative for Chronic Obstructive Lung Diseases (GOLD) criteria. COPD prevalence was associated with sex, age, and smoking status. We found an overall COPD prevalence of 12% (95% CI 11%-13%). Standardized to the Danish population, the true prevalence of COPD is 9% (95% CI 8%-10%). The highest prevalence was observed among current smokers (23%) and former smokers (17%) as well as in the older age group (total = 18%; men = 21%; women = 15%). Most subjects with COPD had mild-to-moderate disease. Among subjects with severe and very severe COPD, 25% were not treated with bronchodilator or inhaled corticosteroids. In conclusion we found that the population prevalence of COPD is high among smokers. A large proportion of persons with COPD did not receive appropriate medical treatment.
BackgroundBone wax is traditionally used as part of surgical procedures to prevent bleeding from exposed spongy bone. It is an effective hemostatic device which creates a physical barrier. Unfortunately it interferes with subsequent bone healing and increases the risk of infection in experimental studies. Recently, a water-soluble, synthetic, hemostatic compound (Ostene®) was introduced to serve the same purpose as bone wax without hampering bone healing. This study aims to compare sternal healing after application of either bone wax or Ostene®.MethodsTwenty-four pigs were randomized into one of three treatment groups: Ostene®, bone wax or no hemostatic treatment (control). Each animal was subjected to midline sternotomy. Either Ostene® or bone wax was applied to the spongy bone surfaces until local hemostasis was ensured. The control group received no hemostatic treatment. The wound was left open for 60 min before closing to simulate conditions alike those of cardiac surgery. All sterni were harvested 6 weeks after intervention.Bone density and the area of the bone defect were determined with peripheral quantitative CT-scanning; bone healing was displayed with plain X-ray and chronic inflammation was histologically assessed.ResultsBoth CT-scanning and plain X-ray disclosed that bone healing was significantly impaired in the bone wax group (p < 0.01) compared with the other two groups, and the former group had significantly more chronic inflammation (p < 0.01) than the two latter.ConclusionBone wax inhibits bone healing and induces chronic inflammation in a porcine model. Ostene® treated animals displayed bone healing characteristics and inflammatory reactions similar to those of the control group without application of a hemostatic agent.
Mutations in the gene for desmoplakin (DSP) may cause arrhythmogenic right ventricular cardiomyopathy (ARVC) and Carvajal syndrome (CS). Desmoplakin is part of all desmosomes, which are abundantly expressed in both myocardial and epidermal tissue and serve as intercellular mechanical junctions. This study aimed to investigate protein expression in myocardial and epidermal tissue of ARVC and CS patients carrying DSP mutations in order to elucidate potential molecular disease mechanisms. Genetic investigations identified three ARVC patients carrying different heterozygous DSP mutations in addition to a homozygous DSP mutation in a CS patient. The protein expression of DSP in mutation carriers was evaluated in biopsies from myocardial and epidermal tissue by immunohistochemistry. Keratinocyte cultures were established from skin biopsies of mutation carriers and characterized by reverse transcriptase polymerase chain reaction, western blotting, and protein mass spectrometry. The results showed that the mutation carriers had abnormal DSP expression in both myocardial and epidermal tissue. The investigations revealed that the disease mechanisms varied accordingly to the specific types of DSP mutation identified and included haploinsufficiency, dominant-negative effects, or a combination hereof. Furthermore, the results suggest that the keratinocytes cultured from patients are a valuable and easily accessible resource to elucidate the effects of desmosomal gene mutations in humans.
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