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Despite clinical importance of ventricular repolarisation, it remains difficult to analyse. Conventionally, quantification of the electrocardiographic ventricular repolarization is usually performed with reference to axis of the T wave and QT interval duration. A variety of factors can prolong the QT interval, such as drug effects, electrolyte imbalances, and myocardial ischemia. The biggest risk with prolongation of the QT interval is the development of torsades de pointes. Commonly accepted reference ranges for the electrocardiogram (ECG) have been in use, with little change, for many years. Populations throughout the world present several differences: age, ethnic compositions, and are exposed to different environmental factors. Recent studies have reported reference data for QT interval in healthy population and have evaluated the influence of age, gender, QRS duration and heart rate on this interval. In this review, we address several issues relative to the measurement, and interpretation of QT interval and its adjustment for rate, age, gender and QRS duration.

Aims: To assess whether a strategy of invasive management without stents in selected acute coronary syndrome (ACS) patients with a large thrombus burden (LTB) might be feasible and safe.\ud \ud Methods and results: We performed a prospective non-randomised observational cohort study of invasive treatment decisions guided by optical coherence tomography (OCT) in selected ACS patients with LTB. Among 852 ACS patients who had undergone invasive coronary angiography, 101 (11.8%) patients with large thrombus burden on initial angiography underwent thrombectomy to restore TIMI 3 flow without stenting. All of these patients then had repeat angiography with OCT (days 0-2 [Group 1], days 3-6 [Group 2] or days 7-30 [Group 3]). No adverse events occurred between the initial and second angiograms. Residual thrombus was detected in 68% of patients with OCT (respectively, 94%, 79% and 32% in Group 1, Group 2 and Group 3), and 20% of cases with angiography. Plaque rupture was detected by OCT in 65% of cases. Minimal lumen area was 2.81 mm2, 3.40 mm2 and 4.89 mm2 in Group 1, Group 2 and Group 3, respectively. Sixty-two percent of patients were stented (respectively, 76%, 61% and 50%). During a minimum follow-up period of 12 months in all patients, one non-fatal MI occurred and one PCI was performed for angina.\ud \ud Conclusions: Medical management without stents is safe and feasible in selected ACS patients with LTB. OCT revealed culprit lesion characteristics that were not disclosed by angiography and facilitated treatment decisions.

IntroductionCoarctation of the aorta (CoA) is a stenosis usually located in the isthmus of the descending aorta. Treatment consists of surgical or percutaneous removal of the obstruction and may present excellent immediate results. However, despite immediate good results, significant residual problems often persist. The aim of the study is to describe the presentation, treatment and long-term evolution of a population of 48 unselected consecutive patients with CoA in a single pediatric cardiology center.MethodsThis was a retrospective study of all patients with isolated CoA associated or not to either atrial or ventricular septal defects. RESULTS: The patients (n = 48, 56,3% male) were diagnosed at a mean age of 84 ± 109 months. The clinical presentation differed between patients aged less or more than two years, the former presenting with heart failure and the latter being asymptomatic with evidence of hypertension (p < 0.01). Treatment was surgical in all cases (32 end-to-end anastomosis). The mean age of patients was 94 ± 109 months. There was two late deaths, in a mean follow-up of 8,6 ± 7,7 years. Recoarctation occurred in 12 patients (25%). There are patients who currently have hypertension (17 at rest, 2 with effort), their mean age at diagnosis being older than the others (128 vs. 76 months; p < 0.05). Aortic aneurysms occurred in five patients (10,4%). Aneurysm was associated to bicuspid aortic valve in 3 cases.Conclusionsrepaired CoA has a significant incidence of long-term complications, and should thus no longer be seen as a simple obstruction in the descending aorta, but rather as a complex pathology that requires careful follow-up after treatment.

Background Time-domain optical coherence tomography (TD-OCT) allows assessment of the anatomy and features of unstable coronary artery lesions, including discrimination between the thrombotic and atherosclerotic plaque components. We sought to investigate the feasibility of thrombus quantification and its monitoring in patients with high thrombotic burden acute coronary syndromes. Methods Patients with successfully revascularized acute coronary syndromes and a large thrombus burden on initial coronary angiography who beneficiated from repeated TD-OCT examinations in our institution were suitable for inclusion. Coronary lesion stenosis degree was determined by quantitative coronary angiography (QCA) methods. Thrombus volume, maximal surface and minimal luminal area (MLA) were quantified by serial area measurement within the athero-thrombotic culprit lesion in 1 mm intervals before any stenting. Results Eleven patients underwent 2 consecutive TD-OCT examinations. The OCT image quality was suitable for thrombus quantification in n=9 subjects (89% men/ age=62.4±5.7y/ 89% STEMI). All patients were under anticoagulant and dual antiplatelet therapy between the two procedures (mean delay: 4.1±0.4 days). No adverse events were observed following OCT analysis. We measured a progressive reduction of thrombus burden between the two analysis, as assessed by the decrease of thrombus volume (5.3±1.7 vs.11.0±3.4 mm3, p=0.004), length (7.4±1.0 vs. 10.9±1.8 mm, p=0.02) and increase of MLA (2.5±0.6 mm2 vs. 1.8±0.3 mm2, p=0.02). However, the degree of stenosis analyzed by QCA didn’t significantly decrease over time (49.7±4.6% vs. 55.7±6.6%, p= 0.15). The thrombus volume reduction was time dependent, as witnessed by the high correlation between the percentage of thrombus volume decrease and the delay between analysis (R=0.87, p=0.002). The observed thrombus volume reduction rate was evaluated to 12% of the initial volume per day under medical therapy. Conclusion TD-OCT assessment of thrombus volume in patients with ACS is feasible, safe and could allow in vivo clot regression monitoring.