[DMEK in complicated cases of bullous keratopathy after multiple intraocular surgeries]. / DMEK bei komplizierten Fällen einer bullösen Keratopathie nach multiplen Augenoperationen.

BACKGROUND: During the last decade Descemet membrane endothelial keratoplasty (DMEK) has been established as a surgical treatment even for complex cases of bullous keratopathy. MATERIAL AND METHODS: In a case series 9 eyes from 8 patients with chronic corneal edema caused by multiple intraocular operations underwent DMEK surgery. It was the sole surgical procedure in three eyes. In one case DMEK was combined with an intravitreal injection of bevacizumab, with opacified intraocular lens exchange in a second case, with transscleral cyclophotocoagulation with Iridex micropulse laser (Iridex, Silicon Valley, CA, USA) and intravitreal injection of bevacizumab in a third case and with the Tutopatch® (DMR srl, Italy) coverage of a scleral perforation in a fourth case. Additionally, DMEK was combined with trimming of the Ahmed valve tube length in two cases. The follow-up period was 12 months. RESULTS: Out of 9 eyes 2 showed a persistent partial or total detachment of the graft with concomitant recurrence of bullous keratopathy despite repeated injection of 20% sulfur hexafluoride (SF6) in the anterior chamber. These 2 eyes were treated with penetrating keratoplasty and achieved satisfactory postoperative results including pain relief. Visual acuity did not improve in these 2 eyes due to optic atrophy. Visual acuity and pain improved in the first postoperative month in 7 eyes. Donor endothelial cell density decreased from 2465±147/mm2 to 1295 ± 254/mm2 and 1180 ± 197/mm2 (p < 0.001, n = 7) after 6 and 12 months, respectively. Central corneal thickness decreased from 880 ± 232 µm to 571 ± 15 µm (p = 0.001, n = 7) after 12 months. Multiple rebubblings were performed in 2 of the 9 eyes because of a persistent corneal graft detachment. CONCLUSION: Although DMEK is a technically demanding surgical treatment for complicated cases of severe bullous keratopathy, it provides satisfactory results in terms of the improvement of visual acuity, pain relief and a shorter postoperative period.

Stress-delta B-type Natriuretic Peptide Levels as a Test for Inducible Myocardial Ischemia: A Systematic Review and Meta-Analysis.

Background Cardiac ischemia induces myocardial dysfunction and ventricular wall stretch, which causes the release of B-type natriuretic peptide (BNP) into the bloodstream. However, it is unclear whether inducible ischemia produces a significant change in BNP levels ("stress delta-BNP"). The objective of this study was to determine the utility of stress-delta BNP levels and its precursor NT-proBNP for detecting inducible myocardial ischemia during cardiac stress testing. Methods We conducted a systematic review and meta-analysis. We searched PubMed, EMBASE, Web of Science, Cumulative Index of Nursing and Allied Health Literature (CINAHL), and Ovid. Studies examining the changes in levels of BNP and its precursor, N-terminal pro-B-type natriuretic peptide (NT-proBNP), after an exercise cardiac stress test were included. Two reviewers independently analyzed titles and abstracts. Abstracts that did not provide enough information regarding eligibility criteria were kept for full-text evaluation. The same two reviewers also performed data extraction for analyses. Any disagreement was resolved by a consensus and, if it persisted, by a third reviewer adjudication. We report the median and mean values in studies in the order of sample size. Results A total of 15 studies met the inclusion criteria. Nine studies reported results in medians and six studies reported results in means. Of the nine studies, five assessed BNP alone, three assessed NT-proBNP, and one assessed both. Due to the non-normal distribution of results in these studies, they could not be meta-analyzed. Of the six studies that reported results in means, three assessed BNP and three assessed NT-proBNP. The standardized difference between normal and ischemic patients' stress-delta BNP values was -0.39 (95% confidence interval (CI): -0.61; -0.17) in a fixed-effects model and -0.73 (95% CI: -1.72; 0.28) in the random-effects model with high heterogeneity (I^2 = 94%, Q test P = 0.001). For NT-proBNP, the meta-analysis model showed no significant difference between the stress-delta test for ischemic and normal patients (standardized mean difference (SMD): -0.02, 95% CI: -0.31; 0.28). Patients without inducible ischemia appeared to have a lower baseline BNP and NT-proBNP compared to patients with inducible ischemia by stress testing. Although some studies report higher stress-delta BNP in the ischemic group, this pattern was not seen consistently across studies. There was high heterogeneity across studies which was not robust to sensitivity analysis. A random-effects model failed to find statistically significant differences in stress-delta BNP or NT-proBNP. Conclusions We failed to find a relationship between stress-delta BNP or NT-proBNP and the presence or absence of ischemia. This may be due to high heterogeneity in the underlying studies.

Incremental value of high-frequency QRS analysis for diagnosis and prognosis in suspected exercise-induced myocardial ischaemia.

AIM: Exercise stress testing is used to detect myocardial ischaemia, but is limited by low sensitivity and specificity. The authors investigated the value of the analysis of high-frequency QRS components as a marker of abnormal depolarization in addition to standard ST-deviations as a marker of abnormal repolarization to improve the diagnostic accuracy. METHODS AND RESULTS: Consecutive patients undergoing bicycle exercise stress nuclear myocardial perfusion imaging were prospectively enrolled. Presence of myocardial ischaemia, the primary diagnostic endpoint, was adjudicated using MPI and coronary angiography. Automated high-frequency QRS analysis was performed in a blinded fashion. The prognostic endpoint was major adverse cardiac events (MACEs) during two years of follow-up. Exercise-induced ischaemia was detected in 147/662 patients (22%). The sensitivity of high-frequency QRS was similar to ST-deviations (46% vs. 43%, p=0.59), while the specificity was lower (75% vs. 87%, p<0.001). The combined use of high-frequency QRS and ST-deviations classified 59% of patients as 'rule-out' (both negative), 9% as 'rule-in' (both positive) and 32% in an intermediate zone (one test positive). The sensitivity for 'rule-out' and the specificity for 'rule-in' improved to 63% and 97% compared with ST-deviation analysis alone (both p<0.001). MACE-free survival was 90%, 80% and 42% in patients in the 'rule-out', intermediate and 'rule-in' groups (p<0.001). After adjustment for age, gender, ST-deviations and clinical post-test probability of ischaemia, high-frequency QRS remained an independent predictor for the occurrence of MACEs. CONCLUSION: The use of high-frequency QRS analysis in addition to ST-deviation analysis improves the diagnostic accuracy during exercise stress testing and adds independent prognostic information.