Project description:Background Marfan syndrome (MFS) is a genetically transmitted connective tissue disorder characterized by aortic root dilatation, dissection, and rupture. Molecularly, MFS pathological features have been shown to be driven by increased angiotensin II in the aortic wall. Using an angiotensin II-driven aneurysm mouse model, we have recently demonstrated that local inhibition of leptin activity restricts aneurysm formation in the ascending and abdominal aorta. As we observed de novo leptin synthesis in the ascending aortic aneurysm wall of patients with MFS, we hypothesized that local counteracting of leptin activity in MFS may also prevent aortic cardiovascular complications in this context. Methods and Results Fbn1C1039G/+ mice underwent periaortic application of low-dose leptin antagonist at the aortic root. Treatment abolished medial degeneration and prevented increase in aortic root diameter (P<0.001). High levels of leptin, transforming growth factor β1, Phosphorylated Small mothers against decapentaplegic 2, and angiotensin-converting enzyme 1 observed in saline-treated MFS mice were downregulated in leptin antagonist-treated animals (P<0.01, P<0.05, P<0.001, and P<0.001, respectively). Leptin and angiotensin-converting enzyme 1 expression levels in left ventricular cardiomyocytes were also decreased (P<0.001) and coincided with prevention of left ventricular hypertrophy and aortic and mitral valve leaflet thickening (P<0.01 and P<0.05, respectively) and systolic function preservation. Conclusions Local, periaortic application of leptin antagonist prevented aortic root dilatation and left ventricular valve remodeling, preserving left ventricular systolic function in an MFS mouse model. Our results suggest that local inhibition of leptin may constitute a novel, stand-alone approach to prevent MFS aortic root aneurysms and potentially other similar angiotensin II-driven aortic pathological features.
Project description:BackgroundCoarctation of aorta (COA) results in chronic left ventricular (LV) pressure overload and subsequently leads to LV diastolic dysfunction and heart failure over time. The goal of COA intervention is to prevent these complications. The timing of COA interventions is based on the presence of these COA severity indices: doppler mean COA gradient, systolic blood pressure, upper-to-lower-extremity SBP gradient, aortic isthmus ratio, presence of collaterals, and exercise-induced hypertension. Although these indices are physiologically intuitive, the relationship between these indices and LV diastolic dysfunction and exertional symptoms has not been studied. The purpose of this study was to evaluate the association between the indices of COA severity and LV diastolic function and symptoms.MethodsIn this cross-sectional study, multivariate linear and logistic regression analyses were used to assess the correlation between indices of COA severity, LV diastolic function (average e' and E/e'), and exertional symptoms (NYHA II-IV and peak oxygen consumption).ResultsOf all the COA indices analyzed in 546 adult COA patients, aortic isthmus ratio had the strongest correlation with e' (β [95% CI]: 3.11 [2.02-4.31]; P=0.014) per 1 cm/second; E/e' (-13.4 [-22.3 to -4.81]; P=0.009) per 1 unit; peak oxygen consumption (4.05 [1.97-6.59] per 1% change, P=0.019), and NYHA II to IV symptoms (odds ratio, 2.16 [1.65-3.18]; P=0.006).ConclusionsOf all the COA severity indices stipulated in the guidelines, aortic isthmus ratio had the strongest correlation with LV diastolic function and exertional symptoms. As LV diastolic dysfunction typically precede heart failure symptoms, we anticipate that the results of this study will improve and simplify patient selection for COA intervention and potentially improve long-term outcomes.
Project description:The left ventricular outflow tract (LVOT) malformations aortic valve stenosis (AVS), coarctation of the aorta (CoA), and hypoplastic left heart syndrome (HLHS) are significant causes of infant mortality. These three malformations are thought to share developmental pathogenetic mechanisms. A strong genetic component has been demonstrated earlier, but the underlying genetic etiologies are unknown. Our objective was to identify genetic susceptibility loci for the broad phenotype of LVOT malformations. We genotyped 411 microsatellites spaced at an average of 10 cM in 43 families constituting 289 individuals, with an additional 5 cM spaced markers for fine mapping. A non-parametric linkage (NPL) analysis of the combined LVOT malformations gave three suggestive linkage peaks on chromosomes 16p12 (NPL score (NPLS)=2.52), 2p23 (NPLS=2.41), and 10q21 (NPLS=2.14). Individually, suggestive peaks for AVS families occurred on chromosomes 16p12 (NPLS=2.64), 7q36 (NPLS=2.31), and 2p25 (NPLS=2.14); and for CoA families on chromosome 1q24 (NPLS=2.61), 6p23 (NPLS=2.29), 7p14 (NPLS=2.27), 10q11 (NPLS=1.98), and 2p15 (NPLS=2.02). Significant NPLS in HLHS families were noted for chromosome 2p15 (NPLS=3.23), with additional suggestive peaks on 19q13 (NPLS=2.16) and 10q21 (NPLS=2.07). Overlapping linkage signals on 10q11 (AVS and CoA) and 16p12 (AVS, CoA, and HLHS) led to higher NPL scores when all malformations were analyzed together. In conclusion, we report suggestive evidence for linkage to chromosomes 2p23, 10q21, and 16p12 for the LVOT malformations of AVS, CoA, and HLHS individually and in a combined analysis, with a significant peak on 2p15 for HLHS. Overlapping linkage peaks provide evidence for a common genetic etiology.
Project description:BackgroundThe aim of this study was to compare left ventricular (LV) remodeling using myocardial strain between patients with severe aortic stenosis (AS) treated with transcatheter aortic valve replacement (TAVR) with and without prosthesis-patient mismatch (PPM).Methods and resultsIn a retrospective study, speckle-tracking echocardiography was used to measure global longitudinal strain (GLS) and strain rate (GLSR), circumferential strain, and rotation before and at mid-term follow-up post-TAVR. Moderate and severe PPM were defined as an effective orifice area ?0.85 and <0.65 cm(2)/m(2), respectively. A total of 102 patients (median age, 83 years [77-88]) with severe AS were included. At 6±3 months post-TAVR, moderate and severe PPM were found in 32 (31%) and 9 (9%) patients. Patients without PPM had a significant regression in LV mass (from 134±41 to 119±38 g/m(2); P=0.001) at follow-up whereas those with PPM did not. There was a significant improvement in LV GLS (-12.8±4.0 to -14.3±4.3%; P=0.01), GLSR (-0.61±0.20 to -0.73±0.25 second(-1); P<0.001), and early diastolic strain rate (0.52±0.20 to 0.64±0.20 second(-1); P<0.001) in patients without PPM, but not in those with PPM. After adjustment for pre-TAVR ejection fraction and post-TAVR aortic regurgitation, patients without PPM had greater improvement in LV longitudinal strain parameters compared to those with PPM. After a median follow-up of 46.1 months (interquartile range, 35.4-60.8), there was no difference in survival between patients with and without PPM.ConclusionsTAVR was associated with an incidence of PPM of 40%. Greater reverse LV remodeling using myocardial strain was evident in patients without PPM compared to PPM. Presence of PPM was not associated with mortality.
Project description:The major clinical features of myocardial noncompaction are heart failure, arrhythmias, and thromboembolic events. Prominent myocardial trabeculae and deep recesses characteristic of myocardial noncompaction can cause stagnant blood flow and the formation of left ventricular clots. We describe the case of a 62-year-old woman who presented with symptoms of heart failure secondary to left ventricular noncompaction. Transthoracic and transesophageal echocardiography revealed multiple left ventricular thrombi, which had formed despite the patient's long-term therapy with aspirin. Anticoagulative therapy should be considered for patients with myocardial noncompaction who also have risk factors for thromboembolism, such as atrial fibrillation, a history of systemic embolism, or severe left ventricular systolic dysfunction. However, chronic antiplatelet therapy may not sufficiently prevent clot formation in patients who have myocardial noncompaction and severe left ventricular systolic dysfunction.
Project description:AimsSeveral coarctation of aorta (COA) severity indices are used for timing of COA intervention, and to define severity of residual coarctation post-intervention. However, it is unclear how many of these COA indices are required in order to recommend intervention, and what degree of residual coarctation results in suboptimal recovery of the left ventricle (LV). Our aim was to assess the correlation between different COA indices and effects of chronic LV pressure overload (LV hypertrophy, diastolic, and systolic dysfunction), and to determine the effect of residual coarctation on LV reverse remodelling after COA intervention.Methods and resultsCOA severity indices were defined as Doppler COA gradient, systolic blood pressure (SBP, upper-to-lower-extremity SBP gradient, aortic isthmus ratio. LV remodelling indices were defined as LV mass index (LVMI), LV global longitudinal strain (LVGLS), e' and E/e'. LV reverse remodelling was defined as the difference between indices obtained pre-intervention and 5-year post-intervention (delta LVMI, e', E/e', LVGLS).Of the COA indices analysed in 546 adult COA patients, aortic isthmus ratio had the strongest correlation with LVMI (β ± standard error -28.3 ± 14.1, P < 0.001), LVGLS (1.51 ± 0.42, P = 0.005), e' (3.11 ± 1.10, P = 0.014), and E/e' (-13.4 ± 6.67, P = 0.008). Residual aortic isthmus ratio also had the strongest correlation with LV reverse remodelling, and residual aortic isthmus ratio <0.7 was predictive of suboptimal LV reverse remodelling post-intervention.ConclusionConsidering the known prognostic implications of LV remodelling and reverse remodelling in response to pressure overload, these results support the use of aortic isthmus ratio for timing of COA intervention, and for prognostication post-intervention.
Project description:Thoracic aortic dissection is a life-threatening complication of Marfan syndrome, a connective tissue disorder caused by mutations in the gene encoding fibrillin-1. We have demonstrated that nitric oxide-mediated endothelial-dependent relaxation is impaired in the thoracic aorta in Marfan syndrome. In the present study, we determined whether the cyclooxygenase (COX)-pathway is involved in the compromised aortic vasomotor function.Thoracic aortae from mice at 3, 6 and 9 months of age, heterozygous for the Fbn1 allele encoding a cysteine substitution (Fbn1 (C1039G/+), 'Marfan', n=35), were compared with those from age-matched controls (n=35).Isometric force measurement revealed that preincubation with indomethacin, a non-specific COX inhibitor, but not valeryl salicylate, a specific COX-1 inhibitor, improved the phenylephrine-induced contractions (at 6 months, EC(50) and E(max) were increased 4.5-fold and by 45%, respectively) in Marfan aortae. Sensitivity to acetylcholine-induced relaxation was improved 10-fold. Blockade of the thromboxane-endoperoxide receptor by SQ-29548 did not affect phenylephrine-mediated contractions in Marfan aortae, although they did respond to the thromboxane analogue, U46619. From 6 months on, phenylephrine-induced secretion of prostacyclin and thromboxane A(2) in Marfan aortae was 200% and 40%, respectively, of those in controls. Reduced COX-1 expression was detected in Marfan aortae at 3 and 9 months, whilst COX-2 expression was increased from 3 months on.The compromised vasomotor function in Marfan thoracic aortae is associated with an imbalanced synthesis of thromboxane A(2) and prostacyclin resulting from the differential protein expression of COX-1 and COX-2.
Project description:The aim of this study was to assess the accuracy of echocardiographic techniques in detecting the early recovery of left ventricular (LV) function after revascularization in acute coronary syndrome (ACS). In 80 consecutive patients with ACS (age 55.7 ± 9.4 years, 77% male, 15% with CCS Angina III), an echocardiographic examination of left ventricle regional wall motion abnormalities (LV RWMA), peak systolic strain rate (PSSR), peak systolic strain (PSS) and end systolic strain (ESS) was performed before and after percutaneous intervention (PCI). Of the 80 patients, one vessel stenosis (>70%) was present in 53 (66%), two vessel disease in 12 (15%) and multivessel disease in 15 patients (19%). In total, 51% of patients had hypertension, 40% diabetes and 23% dyslipidemia. After PCI, regional PSS, ESS and PSSR of their segments subtended by the culprit vessel improved; left anterior descending-LAD, circumflex-LCx and right coronary-RCA (p<0.05 for all) as well as global S and SR (p < 0.05 for all). In univariate analysis, hypertension (HTN) (? = -0.294 (-0.313-0.047), p = 0.009, smoking ? = -0.244 (-0.289-0.015) =0.03, WMA ? = -0.317 (-0.284-0.014), p = 0.004 and the number of diseased vessels ? = -0.256 (-0.188- 0.054) p=0.03 were predictors of delta global SR. In multivariate analysis, only HTN ? = 0.263 (0.005-3.159) and the number of diseased vessels ? =0.263 (0.005 - 3.159), p=0.04) predicted delta global SR. In ACS, the echocardiographic regional myocardial deformation is accurate in detecting early recovery of LV myocardial function after culprit lesion revascularization. Also, the findings of this study support the current practice regarding the crucial importance of proximal epicardial vessel PCI treatment on LV function compared to more distal lesions.
Project description:Massive thoracoabdominal aortic thrombosis is a rare finding in patients with iatrogenic Cushing syndrome in the absence of any coagulation abnormality. It frequently represents an urgent surgical situation. We report the case of an 82-year-old woman with massive aortic thrombosis secondary to iatrogenic Cushing syndrome. A follow-up computed tomography scan showed a decreased amount of thrombus in the aorta after anticoagulation therapy alone.