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51.
Alcohol-induced septal ablation (AISA) is an accepted treatment for hypertrophic cardiomyopathy (HCM) patients with left ventricular (LV) outflow obstruction who are unresponsive to medical therapy. As left atrial (LA) enlargement has been correlated with increased morbidity and mortality in HCM, we assessed LA volumes and ejection fraction (EF) prior to and after AISA using real time three-dimensional (3D) transthoracic echocardiography (TTE) in 12 patients (9 women; mean age 52 ± 15 years; 11 Caucasian). All patients underwent successful AISA with no complications and their resting left ventricular outflow gradients decreased from 40.5 ± 22.2 to 9.1 ± 17.6 mmHg (P < 0.001) while their gradients with provocation decreased from 126.2 ± 31.7 to 21.8 ± 28.0 mmHg (P < 0.001). All patients showed improvements in their New York Heart Association (NYHA) functional class. Both the LA end-systolic (45.2 ± 12.9 to 37.2 ± 13.7 ml, P < 0.0001) and end-diastolic (79.6 ± 18.9 to 77.1 ± 18.6 ml, P = 0.001) volumes decreased after AISA. The LA EF increased from 43.1 ± 9.0 to 52.5 ± 8.8% (P = 0.001). The increase in LA EF correlated with the decrease in the resting left ventricular outflow gradient (R =−0.647, P = 0.03). In conclusion, 3D echocardiography can be utilized to follow LA function after AISA for HCM. AISA results in clinical improvement in patients with HCM and in improvement of LA EF that is correlated with the decrease in the left ventricular outflow gradient.  相似文献   
52.

Background

Myocarditis complicated by cardiogenic shock remains a complex problem. The use of acute mechanical circulatory support devices for cardiogenic shock is growing. We explored the utility of Impella transvalvular microaxial flow catheters in the setting of myocarditis with cardiogenic shock.

Methods and Results

We retrospectively analyzed data from 21 sites within the cVAD registry, an ongoing multicenter voluntary registry at sites in North America and Europe that have used Impella in patients with myocarditis. Myocarditis was defined by endomyocardial biopsy (n?=?11) or by clinical history without angiographic evidence of coronary disease (n?=?23). A total of 34 patients received an Impella 2.5, CP, 5.0, or RP device for cardiogenic shock complicating myocarditis. Baseline characteristics included age 42 ± 17 years, left ventricular ejection fraction (LVEF) 18% ± 10%, cardiac index 1.82 ± 0.46 L·min?1·m?2, pulmonary capillary wedge pressure 25 ± 7 mm Hg, and lactate 27 ± 31 mg/dL. Before Impella placement, 32% (n?=?11) of patients required intra-aortic balloon pump. Mean duration of Impella support was 91 ± 74 hours; 21 of 34 patients (62%) survived the index hospitalization and were discharged with an improved mean LVEF of 37.32% ± 20.31% (P?=?.001); 15 patients recovered with successful support, 5 patients were transferred to another hospital on initial Impella support, 1 patient underwent orthotopic heart transplantation. Ten patients required transition to another mechanical circulatory support device.

Conclusions

This is the largest analysis of Impella-supported myocarditis cases to date. The use of Impella appears to be safe and effective in the settings of myocarditis complicated by cardiogenic shock.  相似文献   
53.
We describe an adult patient with type I aortic dissection in whom it was feasible to demonstrate the extension of the dissection into the innominate artery using color Doppler three-dimensional transesophageal echocardiography.  相似文献   
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The integrin lymphocyte function associated antigen‐1 (LFA‐1) plays a key role in leukocyte trafficking and in adaptive immune responses through interactions with adhesive ligands, such as ICAM‐1. Specific blockade of these interactions has validated LFA‐1 as a therapeutic target in many chronic inflammatory diseases, however LFA‐1 antagonists have not been clinically successful due to the development of a general immunosuppression, causing fatal side effects. Growing evidence has now established that LFA‐1 mediates an array of intracellular signaling pathways by triggering a number of downstream molecules. In this context, a class of multimodular domain‐containing proteins capable of recruiting two or more effector molecules, collectively known as “adaptor proteins,” has emerged as important mediators in LFA‐1 signal transduction. Here, we provide an overview of the adaptor proteins involved in the intracellular signaling cascades by which LFA‐1 regulates T‐cell motility and immune responses. The complexity of the LFA‐1‐associated signaling delineated in this review suggests that it may be an important and challenging focus for future research, enabling the identification of “tunable” targets for the development of immunotherapies.  相似文献   
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We compared findings from intraoperative live/real time three-dimensional transesophageal echocardiography (3DTEE) and two-dimensional transesophageal echocardiography (2DTEE) with surgery in 67 patients having aortic aneurysm and/or aortic dissection. Of these, 20 patients had aortic aneurysm without dissection, 21 aortic aneurysm and dissection, and 26 aortic dissection without aneurysm. 3DTEE diagnosed the type and location of aneurysm correctly in all patients unlike 2DTEE, which missed an aneurysm in one case. There were four cases of aortic aneurysm rupture. Three of them were diagnosed by 3DTEE but only one by 2DTEE, and one missed by both techniques. The mouth of saccular aneurysm, site of aortic aneurysm rupture, and communication sites between perfusing and nonperfusing lumens of aortic dissection could be viewed en face only with 3DTEE, enabling comprehensive measurements of their area and dimensions as well as increasing the confidence level of their diagnosis. In all patients with aortic dissection, 3DTEE enabled a more confident diagnosis of dissection because the dissection flap when viewed en face presented as a sheet of tissue rather than a linear echo seen on 2DTEE which can be confused with an artifact. 2DTEE missed dissection in one patient. In six cases the dissection flap involved the right coronary artery orifice by 3DTEE and surgery. These were missed by 2DTEE. Aortic regurgitation severity was more comprehensively assessed by 3DTEE than 2DTEE. Aneurysm size by 3DTEE correlated well with 2DTEE and surgery/computed tomography scan. In conclusion, 3DTEE provides incremental information over 2DTEE in patients with aortic aneurysm and dissection.  相似文献   
59.
Pai N  Ghosh K  Shetty S 《Annals of hematology》2012,91(9):1471-1476
Approximately, 4-11 % of the patients with idiopathic venous thrombosis (VT) show protein C (PC) deficiency. The molecular pathology of PC deficiency was analyzed in 102 patients; 98 healthy controls were also studied to assess the association of various polymorphisms with reduced PC levels. PROC gene mutations were detected only in 8 (7.8 %) patients with reduced PC levels. PROC promoter region CG polymorphisms showed statistically significant association with reduced PC levels (p < 0.001). PC deficiency in Indian VT patients can, thus, largely be explained by PROC gene promoter CG polymorphisms; only a small fraction of the patients show specific mutations in PROC gene.  相似文献   
60.
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