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Isolated noncompaction of the ventricular myocardium (INVM) is an uncommon cardiomyopathy characterized by the persistence of fetal myocardium with prominent trabecular meshwork and deep intertrabecular recesses, often associated with systolic dysfunction and ventricular dilatation. A 23-year-old man from Burkina Faso was referred to our operative unit with a diagnosis of INVM, made with echocardiogram and magnetic resonance imaging and nonsustained ventricular tachycardia. The literature reports the incidence of malignant ventricular arrhythmias in as many as 47% of the patients and sudden cardiac death in almost 50% of them and this supported our decision to perform implantable cardioverter-defibrillators implantation.  相似文献   
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BACKGROUND: The dermoscopic diagnosis of cutaneous melanoma (CM) may be difficult because some CM lack specific dermoscopic features for melanoma diagnosis. OBJECTIVE: To evaluate whether a diagnosis of CM could be achieved using the classic dermoscopic melanoma-specific criteria, we conducted a retrospective multicenter study of 508 CM samples. METHODS: All the dermoscopic images were analyzed to identify the dermoscopic criteria found in dermoscopically difficult melanomas (DDM) and to examine the possible relation of dermoscopic diagnosis with respect to the difficulty of the dermoscopic diagnosis and the melanoma thickness. RESULTS: A significant percentage of melanomas, 89 of 508 (17.5%), were DDM. The criteria leading to a significant increased risk of DDM were presence of streaks [odds ratio (OR), 2.26; 95% confidence interval (CI), 1.15-4.47), absence or presence of regular pigmentation (OR, 3.41; 95% CI, 1.70-6.85), absence of a blue-whitish veil (OR, 4.04; 95% CI, 2.33-6.99), absence of regression structures (OR, 4.31; 95% CI, 2.42-7.66), and the presence of hypopigmentation (OR, 2.61; 95% CI, 1.49-4.58). CONCLUSION: A significant number of melanomas defy even dermoscopic diagnosis. Only a meticulous comparative and interactive process based on an assessment of all the individual's other nevi ("ugly ducking" sign) and a knowledge about recent changes can lead to the recognition of DDM.  相似文献   
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The purpose of this study was to assess, in patients with ventricular preexcitation, the time dependent physiological variation of antegrade conduction properties in the AV node and in accessory pathways (Aps) as a function of autonomic tone variation induced by posture and physical effort, using noninvasive transesophageal atrial pacing. In 74 WPW patients (mean age 21.31 ± 9.46 yrs), AV node and Kent antegrade effective refractory periods (at pacing cycle lengths 600. 400, and 320 ms), Wenckebach point, shortest preexcited ER intervals during sustained atrial fibrillation (AF) or atrial pacing, as well as the inducibility of AV reentry tachycardia (A VRT) and AF/flutter (AFL) were assessed. AH measurements were carried out at rest, in supine and upright positions, and during effort. A second study was carried out approximately 3 months after the first study. The coefficients of variation (CVs) and reproducibility (CRs) were calculated. For each parameter, the differences between the mean of the two studies were not statistically significant. The CVs and CRs ranged between 0.4% and 4% and between 2 and 28 ms, respectively. AF was induced in 40 (54%) of 74 patients at the first study and in 30 (40.5%) of 74 patients at the second study. AVRT was induced in 33 (45%) of 74 patients at the first study and in 38 (51.3%) of 74 patients at the second study. The reproducibility was 45% for AF/AFL and 65% for reentry tachycardia. Transesophageal atrial pacing is a reliable method for noninvasive reproducible evaluation of ante- grade electroph ysiological properties of both the AV node and APs in WPW patients. However, the effect of autonomic balance variation has to be taken into account and precisely defined because it may significantly affect the inducibility of supraventricular arrhythmias and the estimation of the absolute values of the vulnerable parameters.  相似文献   
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Background: Several studies have searched for predictors of clinical outcome in patients with heart failure (HF). However, since they were collected in clinical trials, most data were subject to selection biases and do not specifically apply to patients with nonischemic heart disease. This study examined the impact of several variables on combined all-cause mortality and hospitalization for cardiac causes, in consecutive ambulatory patients with HF included in the ALPHA registry.
Methods and Results: This analysis included 446 patients with HF and nonischemic heart disease, in New York Heart Association functional class II or III, and a left ventricular (LV) ejection fraction below 40%. In 126 patients (73%) the disease was idiopathic dilated cardiomyopathy, in 72 (16%) hypertensive, in nine (2%) valvular, and in 39 (9%) of other etiologies. The median age was 61 years (range 51–69 years) and 349 (78%) patients were men. Over a median follow-up of 31 months (range 23–40), 82 patients (18%) died or were hospitalized for cardiac causes. In a proportional hazard (Cox) regression model, maximal oxygen consumption (HR 0.9, P = 0.001), LV end-diastolic diameter (HR 1.07, P < 0.001), resting systolic blood pressure (HR 0.97, P < 0.005), and hemoglobin (HR 0.86, P < 0.05) were independent predictors of the combined study endpoint.
Conclusions: In an unselected population of patients with HF and nonischemic heart disease, a reduced exercise capacity, large LV end-diastolic diameter, low systolic blood pressure, and hemoglobin were correlated with long-term all-cause mortality or hospitalization for cardiac causes. These observations may help stratifying and tailoring the treatment of patients with HF and nonischemic heart disease.  相似文献   
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