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981.
OBJECTIVES: To evaluate the role of cutting balloon angioplasty in children with pulmonary artery stenosis. BACKGROUND: Pulmonary artery stenoses can be either congenital or secondary to postoperative scar formation. Isolated multiple small-vessel pulmonary artery stenoses are very rare. No surgical procedures for their treatment are currently available. METHODS: We report on four patients in whom standard and high-pressure balloon angioplasty had failed. Three of the four (2.5-, 3-, and 3.5-years-old; two girls) had isolated multiple peripheral pulmonary artery stenosis. The fourth patient was an 11-month-old girl (8 kg) with tetralogy of Fallot and hypoplastic pulmonary artery branches treated with the implantation of two stents in the pulmonary arteries. During the follow-up this patient developed severe intrastent restenosis and showed severely hypoplasic distal left pulmonary artery. RESULTS: We treated 11 vessels. The mean vessel diameter increased by 81% (P<0.0001) and RV/LV pressure ratio decreased from 1.15 to 0.75 (P=0.05). Patient treated for intrastent restenosis underwent successful complete tetralogy of Fallot repair. None of the patients suffered procedure-related complications. At a median follow-up of 18 months, results were stable and no late complications had occurred. CONCLUSIONS: Cutting balloon angioplasty is a promising technique for the treatment of highly challenging pathologies such as small vessel pulmonary artery stenoses and intrastent restenosis.  相似文献   
982.
ObjectivesThis study sought to explore the Fabry myocardium in relation to storage, age, sex, structure, function, electrocardiogram changes, blood biomarkers, and inflammation/fibrosis.BackgroundFabry disease (FD) is a rare, x-linked lysosomal storage disorder. Mortality is mainly cardiovascular with men exhibiting cardiac symptoms earlier than women. By cardiovascular magnetic resonance, native T1 is low in FD because of sphingolipid accumulation.MethodsA prospective, observational study of 182 FD (167 adults, 15 children; mean age 42 ± 17 years, 37% male) who underwent cardiovascular magnetic resonance including native T1, late gadolinium enhancement (LGE), and extracellular volume fraction, 12-lead electrocardiogram, and blood biomarkers (troponin and N-terminal pro-brain natriuretic peptide).ResultsIn children, T1 was never below the normal range, but was lower with age (9 ms/year, r = −0.78 children; r = −0.41 whole cohort; both p < 0.001). Over the whole cohort, the T1 reduction with age was greater and more marked in men (men: −1.9 ms/year, r = −0.51, p < 0.001; women: −1.4 ms/year, r = −0.47 women, p < 0.001). Left ventricular hypertrophy (LVH), LGE, and electrocardiogram abnormalities occur earlier in men. Once LVH occurs, T1 demonstrates major sex dimorphism: with increasing LVH in women, T1 and LVH become uncorrelated (r = −0.239, p = 0.196) but in men, the correlation reverses and T1 increases (toward normal) with LVH (r = 0.631, p < 0.001), a U-shaped relationship of T1 to indexed left ventricular mass in men.ConclusionsThese data suggest that myocyte storage starts in childhood and accumulates faster in men before triggering 2 processes: a sex-independent scar/inflammation regional response (LGE) and, in men, apparent myocyte hypertrophy diluting the T1 lowering of sphingolipid.  相似文献   
983.
984.
The initial therapy for postmyocardial infarction ventricular septal defects is surgical repair of the defect. Unfortunately, a significant number of patients develop recurrent ventricular septal defects (VSDs) following operative repair. Transcatheter closure offers an alternative to reoperation in these critically ill patients. We present a series of four patients in whom recurrent ventricular septal defects were closed using an Amplatzer VSD device.  相似文献   
985.
We investigated the effects of an angiotensin-converting enzyme inhibitor and an angiotensin II type 1 receptor blocker on cardiac hypertrophy in rats with renovascular hypertension. Renovascular hypertensive (Goldblatt) rats were surgically prepared from Wistar rats. Four weeks later, the rats showed a significant increase in blood pressure. At high doses, both the perindopril (1 mg/kg/day) and the candesartan (2 mg/kg/day) decreased the systolic pressure in these rats to the level of control Wistar rats. At low doses (perindopril 0.1 mg/kg/day and candesartan 0.1 mg/kg/day), these drugs lowered blood pressure to 85% of that in hypertensive rats. Echocardiographic and morphological studies revealed severe cardiac hypertrophy and fibrosis in untreated Goldblatt rats. High-dose treatment with both drugs suppressed the progression of hypertrophy and fibrosis. Also, low-dose perindopril prevented cardiac hypertrophy and fibrosis. In contrast, at the same levels of blood-pressure reduction, low-dose candesartan did not prevent cardiac fibrosis nor the upregulation of cardiac collagen types I and III mRNA observed in untreated Goldblatt rats. Atrial natriuretic peptide mRNA was up-regulated in untreated Goldblatt rats. These changes were significantly decreased by both doses of perindopril or the high dose of candesartan. Serum levels of angiotensin II and aldosterone were significantly higher in untreated Goldblatt rats. Both doses of perindopril inhibited activation of the renin-angiotensin system, whereas candesartan had weaker effects. In particular, serum aldosterone was 347 ± 20 pg/ml in low-dose perindopril versus 1796 ± 324 pg/ml in low-dose candesartan. These results suggest that there were no differences between the cardioprotective actions of perindopril and candesartan at high dosages. On the other hand, low-dose treatment with perindopril was more effective in preventing cardiac fibrosis than was low-dose treatment with candesartan, despite similar changes in blood pressure. It is possible that changes in aldosterone secretion are related to this difference.  相似文献   
986.
BackgroundPatients with out-of-hospital cardiac arrest (OHCA) due to acute coronary syndromes (ACS) who undergo percutaneous coronary intervention (PCI) are at high risk of bleeding and thrombosis. While predictive bleeding and stent thrombosis risk scores have been established, their performance in patients with OHCA has not been evaluated.MethodsAll consecutive patients admitted for OHCA due to ACS who underwent PCI between January 2007 and December 2019 were included. The ACTION and CRUSADE bleeding risk scores and the Dangas score for early stent thrombosis risk were calculated for each patient. A C-statistic analysis was performed to assess the performance of these scores.ResultsAmong 386 included patients, 82 patients (21.2%) experienced severe bleeding and 30 patients (7.8%) experienced stent thrombosis. The predictive performance of the ACTION and CRUSADE bleeding risk scores for major bleeding was poor, with areas under the curve (AUCs) of 0.596 and 0.548, respectively. Likewise, the predictive performance of the Dangas stent thrombosis risk score was poor (AUC 0.513). Using multivariable analysis, prolonged low-flow (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.00–1.05; P = 0.025), reduced haematocrit or fibrinogen at admission (OR 0.93, 95% CI 0.88–0.98; P = 0.010 and OR 0.61; 95% CI 0.41–0.89; P = 0.012, respectively) and the use of glycoprotein IIb/IIIa inhibitors (OR 2.10, 95% CI 1.18–3.73; P = 0.011) were independent risk factors for major bleeding.ConclusionThe classic bleeding and stent thrombosis risk scores have poor performance in a population of patients with ACS complicated by OHCA. Other predictive factors might be more pertinent to determine major bleeding and stent thrombosis risks in this specific population.  相似文献   
987.
《JACC: Cardiovascular Imaging》2019,12(12):2373-2385
ObjectivesThis study sought to compare the prognostic value of 2-dimensional (2D) right ventricular (RV) speckle tracking (STE) against cardiac magnetic resonance (CMR) RV ejection fraction (EF) and feature tracking (FT) and conventional echocardiographic parameters on overall and cardiovascular (CV) survival in patients with heart failure with reduced EF (HFrEF).BackgroundPrior works showed that RV systolic function predicts prognosis in HFrEF. 2D RVSTE had recently been proposed as new echocardiographic method to evaluate RV dysfunction.MethodsA total of 266 patients with HFrEF (mean LVEF 23 ± 7%, 60 ± 14 years of age; 29% women) underwent RV function assessment using CMR and 2D echocardiography and were followed for a primary endpoint of overall death and secondary endpoint of CV death.ResultsAverage CMR-RVEF was 42 ± 15%, average STE RV global longitudinal strain (STE-RVGLS) was −18.0 ± 4.9%, and average CMR-FT-RVGLS was −11.8 ± 4.3%. After a median follow-up of 4.7 years, 102 patients died, 84 of a CV cause. RVEF, FT-RVGLS, tricuspid annulus plane systolic excursion (TAPSE), fractional area change (FAC), and STE-RVGLS were significant univariate predictors of overall and cardiac death. In multivariate Cox regression, age, ischemic etiology, diabetes, New York Heart Association functional class III to IV, and beta-blocker treatment were independent clinical predictors of overall mortality. CMR-RVEF (chi-square to enter = 3.9; p < 0.05), FT-RVGLS (chi-square to enter 3.7; p = 0.05), FAC (chi-square to enter 6.2; p = 0.02), and TAPSE (chi-square to enter = 4.1; p = 0.04) provided additional prognostic value over these baseline parameters, but the additional predictive value of STE-RVGLS (chi-square to enter = 10.8; p < 0.001) was significantly (p < 0.05) higher than the other tests. Additional hazard ratio to predict overall mortality was 2.5 (95% confidence interval [CI]: 1.6 to 3.9) for STE-RVGLS <−19%, 2.15 (95% CI: 1.34 to 3.43) for TAPSE >15 mm, 1.6 (95% CI: 1.02 to 2.49) for FAC >39%, 1.93 (95% CI: 1.25 to 2.99) for RVEF >41%, and 1.87 (95% CI: 1.10 to 3.19) for CMR-FT-RVGLS <−15%.Conclusions2D RVGLS provides strong additional prognostic value to predict overall and CV mortality in HFrEF, with higher predictive value than CMR-RVEF, CMR-FT-RVGLS, TAPSE, or FAC. This supports use of STE-RVGLS to identify higher-risk HFrEF patients.  相似文献   
988.
《JACC: Cardiovascular Imaging》2019,12(12):2517-2537
Rheumatic diseases are immune-mediated inflammatory multisystem diseases with frequent cardiovascular manifestations including perimyocarditis, valvular disease, coronary artery disease, heart failure with or without preserved ejection fraction, pulmonary hypertension, aneurysms, and thrombosis. Echocardiography, carotid ultrasonography, cardiac computed tomography, cardiac magnetic resonance imaging, and positron emission tomography are valid diagnostic tools for the detection of the cardiovascular complications of the multisystem diseases that frequently determine prognosis. Furthermore, the findings of these methods may offer additive risk stratification in asymptomatic patients over the conventional risk scores used to assess cardiovascular risk in the primary prevention setting. Finally, the imaging methods offer a unique opportunity to monitor the effects of treatment on atherosclerotic lesions, coronary microcirculatory dysfunction, myocardial inflammation and fibrosis. However, studies are needed to investigate whether improvement of imaging markers by treatment or selection of treatment according to its effects on surrogate imaging markers is linked to improved prognosis.  相似文献   
989.

Objectives

This study introduced and validated a novel flow-independent delayed enhancement technique that shows hyperenhanced myocardium while simultaneously suppressing blood-pool signal.

Background

The diagnosis and assessment of myocardial infarction (MI) is crucial in determining clinical management and prognosis. Although delayed enhancement cardiac magnetic resonance (DE-CMR) is an in vivo reference standard for imaging MI, an important limitation is poor delineation between hyperenhanced myocardium and bright LV cavity blood-pool, which may cause many infarcts to become invisible.

Methods

A canine model with pathology as the reference standard was used for validation (n = 22). Patients with MI and normal controls were studied to ascertain clinical performance (n = 31).

Results

In canines, the flow-independent dark-blood delayed enhancement (FIDDLE) technique was superior to conventional DE-CMR for the detection of MI, with higher sensitivity (96% vs. 85%, respectively; p = 0.002) and accuracy (95% vs. 87%, respectively; p = 0.01) and with similar specificity (92% vs, 92%, respectively; p = 1.0). In infarcts that were identified by both techniques, the entire length of the endocardial border between infarcted myocardium and adjacent blood-pool was visualized in 33% for DE-CMR compared with 100% for FIDDLE. There was better agreement for FIDDLE-measured infarct size than for DE-CMR infarct size (95% limits-of-agreement, 2.1% vs. 5.5%, respectively; p < 0.0001). In patients, findings were similar. FIDDLE demonstrated higher accuracy for diagnosis of MI than DE-CMR (100% [95% confidence interval [CI]: 89% to 100%] vs. 84% [95% CI: 66% to 95%], respectively; p = 0.03).

Conclusions

The study introduced and validated a novel CMR technique that improves the discrimination of the border between infarcted myocardium and adjacent blood-pool. This dark-blood technique provides diagnostic performance that is superior to that of the current in vivo reference standard for the imaging diagnosis of MI.  相似文献   
990.
ObjectivesThe authors investigated the incremental prognostic value of entropy, a novel measure of myocardial tissue heterogeneity by cardiac magnetic resonance (CMR) imaging in patients presenting with ventricular arrhythmias (VAs).BackgroundCMR can characterize myocardial areas serving as arrhythmogenic substrate.MethodsConsecutive patients undergoing CMR imaging for VAs were followed for major adverse cardiac events (MACEs) defined by all-cause death, incident VAs requiring therapy, or heart failure hospitalization. Entropy was derived from the probability distribution of pixel signal intensities of the left ventricular (LV) myocardium.ResultsA total of 583 patients (age 54 ± 15 years, female 39%, left ventricular ejection fraction [LVEF] 54 ± 13%) were followed for a median of 4.4 years and experienced 141 MACEs. Entropy showed strong unadjusted association with MACE (HR: 1.88; 95% CI: 1.63-2.17; P < 0.001). In a multivariable model including LVEF, QRS duration, late gadolinium enhancement, and presenting arrhythmia, entropy maintained independent association with MACE (HR: 1.61; 95% CI: 1.32-1.96; P < 0.001). Entropy was further significantly associated with MACE in patients without myocardial scar (HR: 2.43; 95% CI: 1.55-3.82; P < 0.001) and in those presenting with nonsustained VAs (HR: 2.16; 95% CI: 1.43-3.25; P < 0.001). Addition of LV entropy to the baseline multivariable model significantly improved model performance (C-statistic improvement: 0.725 to 0.754; P = 0.003) and risk reclassification.ConclusionsIn patients with VAs, CMR-assessed LV entropy was independently associated with MACE and provided incremental prognostic value, on top of LVEF and late gadolinium enhancement. LV entropy assessment may help risk stratification in patients with absence of myocardial scar or with nonsustained VAs.  相似文献   
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