Extent of late gadolinium enhancement detected by cardiovascular magnetic resonance correlates with the inducibility of ventricular tachyarrhythmia in hypertrophic cardiomyopathy

Background

Myocardial fibrosis is frequently identified in patients with hypertrophic cardiomyopathy (HCM). The aim of this study was to investigate the role of myocardial fibrosis detected by late gadolinium-enhancement (LGE) cardiovascular magnetic resonance (CMR) as a potential arrhythmogenic substrate in HCM. We hypothesized that the extent of LGE might be associated with the inducibility of ventricular tachyarrhythmias (VT) during programmed ventricular stimulation (PVS).

Methods

We evaluated retrospectively LGE CMR of 76 consecutive HCM patients, of which 43 presented with one or more risk factors for sudden cardiac death (SCD) and were therefore clinically classified as high-risk patients. Of these 43 patients, 38 additionally underwent an electrophysiological testing (EP). CMR indices and the extent of LGE, given as the % of LV mass with LGE were correlated with the presence of risk factors for SCD and the results of EP.

Results

High-risk patients had a significant higher prevalence of LGE than low-risk patients (29/43 [67%] versus 14/33 [47%]; p = 0.03). Also the % of LV mass with LGE was significantly higher in high-risk patients than in low-risk patients (14% versus 3%, p = 0.001, respectively). Of the 38 high- risk patients, 12 had inducible VT during EP. LV function, volumes and mass were comparable in patients with and without inducible VT. However, the % of LV mass with LGE was significantly higher in patients with inducible VT compared to those without (22% versus 10%, p = 0.03). The prevalence of LGE was, however, comparable between HCM patients with and those without inducible VT (10/12 [83%] versus 15/26 [58%]; p = 0.12). In the univariate analysis the % of LV mass with LGE and the septal wall thickness were significantly associated with the high-risk group (p = 0.001 and 0.004, respectively). Multivariate analysis demonstrated that the extent of LGE was the only independent predictor of the risk group (p = 0.03).

Conclusions

The extent of LGE in HCM patients correlated with risk factors of SCD and the likelihood of inducible VT. Furthermore, LGE extent was the only independent predictor of the risk group. This supports the hypothesis that the extent of fibrosis may serve as potential arrhythmogenic substrate for the occurrence of VT, especially in patients with clinical risk factors for SCD.     

Assessment of the anterior chamber parameters after laser iridotomy in primary angle close suspect using Pentacam and gonioscopy

AIM:To investigate the role of fundus autofluorescence (FAF) both in the diagnosis and the preoperative and postoperative evaluation of patients with idiopathic macular hole (MH).METHODS: Forty eyes of 40 patients diagnosed as idiopathic MH between May 2010 and May 2011 were included in this retrospective study. All patients underwent full ophthalmologic examinations and imagings including fluorescein angiography, fundus autofluorescence (FAF) and optical coherence tomography. Thirty of these patients underwent MH surgery. FAF findings were associated with duration of symptoms, visual acuity at presentation, stage of MH, and postoperative anatomical correction.RESULTS:The mean duration of patients’ symptoms was 3.8±2.0 (1-9) months. The MH was stage 2 in 4 (10%), stage 3 in 24 (60%) and stage 4 in 12 (30%) eyes. The median preoperative best corrected visual acuity was 20/200 (between 20/800 and 20/100). Twenty-eight of cases (70%) showed a stellate appearance with dark radiating striae. Having a visual acuity ≥20/200 was significantly more common in eyes with stellate appearance (P<0.001). The mean duration of symptoms was significantly shorter in eyes with stellate appearance (2.75±0.8 vs 6.33±1.61 months) (P<0.001). The frequency of stage 4 MH was significantly higher in eyes with non-stellate appearance (P<0.001). Anatomical correction of MH was achieved in 91.3% (21/23) of eyes with stellate appearance and 71.4% (5/7) of eyes without this appearance (P=0.225).CONCLUSION: Stellate appearance in FAF is associated with earlier stages of macular hole, better visual acuity at presentation, shorter duration of symptoms, thus more favorable prognosis.     

Modification of Disodium Cromoglycate Passage Across Lung Epithelium In Vitro Via Incorporation into Polymeric Microparticles

Two microparticle systems containing disodium cromoglycate (DSCG) alone or with polyvinyl alcohol (DSCG/PVA) were produced via spray drying and compared in terms of their physicochemical characteristics, aerosol performance and drug uptake across a pulmonary epithelial cell line (Calu-3), cultured under air interface conditions. The particle size distribution of DSCG and DSCG/PVA were similar, of spherical geometry, amorphous and suitable for inhalation purposes. Aerosolisation studies using a modified twin-stage impinger showed the DSCG/PVA to have greater aerosol performance than that of DSCG alone. Aerosol particles of DSCG and DSCG/PVA were deposited onto the surface of the Calu-3 air interface epithelium monolayer and the drug uptake from apical to basal directions measured over time. Drug uptake was measured across a range of doses to allow comparison of equivalent drug and powder mass deposition. Analysis of the data indicated that the percentage cumulative drug uptake was independent of the mass of powder deposited, but dependent on the formulation. Specifically, with the formulation containing DSCG, the diffusion rate was observed to change with respect to time (indicative of a concentration-dependent diffusion process), whilst DSCG/PVA showed a time-independent drug uptake (suggesting a zero-order depot release).     

Influence of Bag Volume on Reproducibility of Inert Gas Rebreathing Pulmonary Blood Flow Measurements in Patients with Pulmonary Diseases

Purpose

Non-invasive inert gas rebreathing (IGR) has shown promising results in the determination of pulmonary blood flow. The volume of the rebreathing bag (V _bag) is proposed by the system. However, elderly patients or those with severe pulmonary disease may be unable to rebreathe this volume entirely. We evaluated the effect of adapting V _bag on the reproducibility of IGR.

Methods

A total of 270 valid measurements were obtained from 45 patients with obstruction (group A), restriction (group B), and in healthy controls (group C). Two measurements for each of three different V _bag of 1,200, 1,700, and 2,200 ml were conducted in the supine position.

Results

We found no statistically significant difference of the repeated measurements neither between the different V _bag in groups A to C nor between the three groups for identical V _bag. There was a weak yet significantly worse coefficient of variation between a V _bag of 2,200 ml in group A compared with group C with 2,200 and 1,200 ml, respectively. Intraclass correlation coefficient and repeatability coefficient yielded significantly worse values in group A for a V _bag of 2,200 ml compared with healthy controls and lower bag volumes. No difference could be found intraclass nor interclass in groups B and C.

Conclusions

V _bag can be altered between 1,200 and 2,200 ml in most situations without affecting the reproducibility. Attention has to be paid to extreme volumes in obstructive patients. Nevertheless, V _bag should be chosen as large as possible and therefore has to be carefully adapted, particularly in patients with obstruction or restriction.     

Is the Frameshift Codons 8/9 (+G) [FSC 8/9 (+G)] β-Thalassemia Mutation,Detected by the Polymerase Chain Reaction-Amplification Refractory Mutation System,Really FSC 8/9 (+G)?

There are several polymerase chain reaction (PCR)-based approaches for the analysis of known mutations. The PCR-amplification refractory mutation system (PCR-ARMS) is one of the best known and frequently used for the detection of β-thalassemia (β-thal) mutations. However, there is an important point to be considered when searching for the frameshift codon (FSC) 8 (–AA) and FSC 8/9 (+G) mutations. Whereas the primer is specific for the FSC 8 mutation only, the primer for the FSC 8/9 mutation does not discriminate between the FSC 8/9 and FSC 8 mutations. Thus, the high number of FSC8/9 mutations reported in countries like India, Pakistan and some regions of Iran may be due to the use of the FSC 8/9 primer, without taking the FSC 8 mutation into account. It is thus advisable to test for FSC 8 before the FSC 8/9 mutation whenever PCR-ARMS is the method of investigation for these two mutations.     

Pulmonary hydatid cyst: analysis of 1024 cases

Purpose  

Pulmonary hydatid cyst, a parasitic disease, is a health care problem in developing countries. In this study, we evaluated outcomes of patients with pulmonary hydatid disease who were treated in our department.     

Plasma coenzyme Q10 levels in type 2 diabetic patients with retinopathy

AIM: To determine the relationship between proliferative diabetic retinopathy (PDRP) and plasma coenzyme Q10(CoQ10) concentration.METHODS: Patients with type 2 diabetes and PDRP were determined to be the case group (n=50). The control group was consist of healthy individuals (n=50). Plasma CoQ10 and malondialdehyde (MDA) levels were measured in both groups.RESULTS: Ubiquinone-10 (Coenzyme Q10) levels in PDRP and control subjects are 3.81±1.19μmol/L and 1.91±0.62μmol/L, respectively. Plasma MDA levels in PDRP and control subjects were 8.16±2μmol/L and 3.44±2.08μmol/L, respectively. Ratio of Ubiquinol-10/ubiquinone-10 in PDRP and control subjects were 0.26±0.16 and 1.41±0.68, respectively.CONCLUSION:The ratio of ubiquinol-10/ubiquinone-10 is found lower in patients with PDRP. High levels of plasma ubiquinol-10/ubiquinone-10 ratio indicate the protective effect on diabetic retinopathy.