64 slice-coronary computed tomography sensitivity and specificity in the evaluation of coronary artery bypass graft stenosis: A meta-analysis.

A non-invasive approach to define grafts patency and stenosis in the follow-up of coronary artery bypass graft (CABG) patients may be an interesting alternative to coronary angiography. 64-slice-coronary computed tomography is nowadays a diffused non-invasive method that permits an accurate evaluation of coronary stenosis, due to a high temporal and spatial resolution. However, its sensitivity and specificity in CABG evaluation has to be clearly defined, since published studies used different protocols and scanners. We collected all studies investigating patients with stable symptoms and previous CABG and reporting the comparison between diagnostic performances of invasive coronary angiography and 64-slice-coronary computed tomography. As a result, sensitivity and specificity of 64-slice-coronary computed tomography for CABG occlusion were 0.99 (95% CI 0.97-1.00) and 0.99 (95% CI: 0.99-1.00) with an area under the curve (AUC) of 0.99. 64-slice-coronary computed tomography sensitivity and specificity for the presence of any CABG stenosis >50% were 0.98 (95% CI: 0.97-0.99) and 0.98 (95% CI: 0.96-0.98), while AUC was 0.99. At meta-regression, neither the age nor the time from graft implantation had effect on sensitivity and specificity of 64-slice-coronary computed tomography detection of significant CABG stenosis or occlusion. In conclusion 64-slice-coronary computed tomography confirmed its high sensitivity and specificity in CABG stenosis or occlusion evaluation.

Prevalence and predictors of culprit plaque rupture at OCT in patients with coronary artery disease: a meta-analysis.

AIMS: The prevalence of plaque rupture at the culprit lesion identified by optical coherence tomography (OCT) in different clinical subset of patients undergoing coronary angiography and its clinical predictors remain to be defined. METHODS: All studies including patients with OCT evaluation of the culprit coronary plaque were included. The prevalence of culprit plaque rupture (CPR) and thin-cap fibro-atheroma (TCFA) were the primary endpoints. The factors associated with these findings were studied in a subset of patients with different clinical presentations [ST-elevation myocardial (STEMI) vs. nonST-elevation myocardial infarction (NSTEMI) vs. unstable angina (UA) vs. stable angina pectoris (SAP)]. RESULTS: One hundred and fifty citations were initially appraised at the abstract level and 23 full-text studies were assessed. The mean prevalence of CPR and TCFA was 48.1% (40.5-55.8) and 48.7% (37.4-60.1), respectively. The prevalence of CPR and TCFA were higher in STEMI (70.4 and 76.6%) than in NSTEMI (55.6 and 56.3%) and UA (39.1 and 52.9%) or SAP (6.2 and 22.8%). In the overall population at meta-regression analysis, TCFA and current smoking were the only predictors of CPR (B 3.6:2.0-5.1, P < 0.001 and 0.06:0.02-0.1, P = 0.002, respectively). The factors associated with CPR were different depending on clinical presentation. Hypertension was the only clinical predictor for STEMI (B 3.3: 1.2.-5.3 P = 0.001), while advanced age (B 0.12: 0.02-0.22, P = 0.021), diabetes mellitus (B 0.04: 0.01-0.08, P = 0.012), and hyperlipidaemia (B 0.07:0.02-0.11, P = 0.005) were the predictors in NSTEMI and UA. No clinical predictor was found in SA. CONCLUSIONS: Our analysis showed high rates of CPR and TCFA detected by OCT in CAD patients, especially in those with ACS, although their prevalence is not negligible in stable patients. TCFA seems to be a strong predictor of CPR in all the ACS scenarios.

New echocardiographic insights in short QT syndrome: More than a channelopathy?

BACKGROUND: Short QT syndrome (SQTS) is a congenital ion channel disease characterized by an increased risk of sudden cardiac death. Little is known about the possibility that accelerated repolarization alters mechanical function in SQTS. OBJECTIVES: The study investigated the presence of left ventricular dysfunction and mechanical dispersion, assessed by tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE), and their correlation with QT interval duration and genetics. METHODS: Fifteen SQTS patients (7 with HERG and 3 with KCNQ1 mutation) were studied. Electrocardiographic and echocardiographic parameters were compared with age- and sex-matched healthy controls. RESULTS: When compared to the control group, SQTS patients showed reduced left ventricular contraction (global longitudinal strain: -16.0% ± 3.4% vs -22.6% ± 1.7%, P < .001; myocardial performance index 0.59 ± 0.17 vs 0.34 ± 0.08, P < .001) and a higher incidence of ejection fraction <55% (odds ratio 11, 95% confidence interval 1.045-374, P = .04). Mechanical dispersion assessed by TDI (P < .01) and STE (P < .001) was higher in the SQTS group than in controls; each parameter showed a significant inverse correlation with QT interval but not with QT dispersion. CONCLUSION: This study showed that in SQTS systolic function may also be affected. SQTS patients presented a significant dispersion of myocardial contraction. TDI and STE could become part of the evaluation of this rare disease.

Fluorescent reporter proteins for the tonoplast and the vacuolar lumen identify a single vacuolar compartment in Arabidopsis cells.

We generated fusions between three Arabidopsis (Arabidopsis thaliana) tonoplast intrinsic proteins (TIPs; alpha-, gamma-, and delta-TIP) and yellow fluorescent protein (YFP). We also produced soluble reporters consisting of the monomeric red fluorescent protein (RFP) and either the C-terminal vacuolar sorting signal of phaseolin or the sequence-specific sorting signal of proricin. In transgenic Arabidopsis leaves, mature roots, and root tips, all TIP fusions localized to the tonoplast of the central vacuole and both of the lumenal RFP reporters were found within TIP-delimited vacuoles. In embryos from developing, mature, and germinating seeds, all three TIPs localized to the tonoplast of protein storage vacuoles. To determine the temporal TIP expression patterns and to rule out mistargeting due to overexpression, we generated plants expressing YFP fused to the complete genomic sequences of the three TIP isoforms. In transgenic Arabidopsis, gamma-TIP expression was limited to vegetative tissues, but specifically excluded from root tips, whereas alpha-TIP was exclusively expressed during seed maturation. delta-TIP was expressed in vegetative tissues, but not root tips, at a later stage than gamma-TIP. Our findings indicate that, in the Arabidopsis tissues analyzed, two different vacuolar sorting signals target soluble proteins to a single vacuolar location. Moreover, TIP isoform distribution is tissue and development specific, rather than organelle specific.