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121.
Khanna D Sinha A Nanda NC Gupta R Sidhu M Vengala S Dod HS Ilgenli TF 《Echocardiography (Mount Kisco, N.Y.)》2004,21(4):349-353
In the current study, we describe an adult patient with torrential aortic regurgitation due to an aortic dissection flap interfering with aortic cusp motion, in whom a transesophageal echocardiogram with the probe positioned in the upper esophagus and transpharyngeal ultrasound examination demonstrated prominent reversed flow throughout diastole in the left subclavian, left vertebral, left common carotid, and left internal carotid arteries. Another unique finding was the demonstration of aortic valve leaflets held in the fully opened position in diastole by the dissection flap as it prolapsed into the left ventricular outflow tract, dramatically documenting the mechanism of torrential aortic regurgitation in this patient. 相似文献
122.
Maneesha Bhaya M.D. Ferit Onur Mutluer M.D. Edward Mahan M.D. Luke Mahan Ming C. Hsiung M.D. Wei–Hsian Yin M.D. Ph.D. Jeng Wei M.D. MsD Shen–Kou Tsai M.D. Ph.D. Guang–Yu Zhao M.D. Wei–Hsian Yin M.D. Manish Pradhan M.D. Rajesh Beniwal M.D. Deepak Joshi M.D. Fatemeh Nabavizadeh M.D. Amitoj Singh M.B.B.S. Navin C. Nanda M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(3):345-353
123.
124.
Kamel Sadat M.D. Hari Prakash Diddi M.B.B.S. Berthold Klas B.S. Ayman Haj Asaad M.D. Elif İjlal Çekirdekçi M.D. Aylin Sungur M.D. Selvin Sudhakar M.D. Matthew Cain M.D. Arshad Kamal M.D. Navin C. Nanda M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(10):1227-1231
Hypertrophic cardiomyopathy (HCM) is the most common genetically transmitted cardiomyopathy. In patients resistant to medical management, myectomy is the surgical procedure of choice to reduce the symptoms of left ventricular outflow obstruction. Two‐dimensional transesophageal echocardiography (2DTEE) has become part of the operative procedure by decreasing the incidence of postoperative complications. However, because of the three‐dimensional geometry of left ventricular outflow tract, it is unable to comprehensively assess the location and severity of the obstruction and to provide accurate guidance during myectomy. In this study, 10 patients with HCM underwent live/real time three‐dimensional transesophageal echocardiography (3DTEE) intra‐operatively to measure the volume of the resected septum. This volume correlated well with the volume of the resected septal muscle directly obtained using a graduating cylinder containing water (r = 0.9, P < 0.000). 3DTEE may be potentially used as an adjunct to guide the surgeon in performing an adequate myectomy with a lower incidence of residual obstruction and complications such as an iatrogenic ventricular septal defect. 相似文献
125.
Yumiko Kanei Navin C. Nakra Michael Liou Jagdeep Singh John T. Fox Tak W. Kwan 《Cardiovascular Revascularization Medicine》2013,14(2):81-83
BackgroundBifurcation lesions at the time of emergent PCI for STEMI are relatively common. However, there are little data regarding their significance. The objective of this study is to evaluate the impact of bifurcation lesions in the setting of emergent percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI).MethodsIn 391 patients who underwent primary and rescue PCI, the clinical characteristics, procedural success, and in-hospital cardiac events were compared retrospectively between the patients with and without bifurcation lesions. The PCI strategy was at the discretion of the operator.ResultsThe culprit artery involved a bifurcation lesion in 54/391 (14%) patients. The baseline clinical characteristics between the groups with and without bifurcation lesions were similar. The majority of bifurcation lesions (81%) were seen in the left anterior ascending (LAD) artery. All lesions were treated with the provisional stenting approach, and only 2 (3%) patients required 2 stents. There were no difference in the procedural success and the final TIMI-3 flow, but PCI of bifurcation lesion required higher amount of contrast use. There was no in-hospital MACE in the bifurcation group. The peak cardiac enzyme, left ventricular function, and length of stay were similar in these 2 groups.ConclusionsBifurcation lesions are relatively common in emergent PCI for STEMI involving the LAD. It can be safely treated with a provisional stenting approach, and the immediate outcome is similar to non-bifurcation lesions. 相似文献
126.
Angel L��pez-Candales Navin Rajagopalan Beth Gulyasy Kathy Edelman Raveen Bazaz 《The Canadian journal of cardiology》2009,25(3):e73-e77
BACKGROUND:
In contrast to the homogeneously distributed deformation properties within the left ventricle, the right ventricular (RV) free wall (RVFW) shows a more inhomogeneous distribution. It has been demonstrated that pulmonary hypertension (PH) results in significant RVFW mechanical delay.OBJECTIVE:
To assess the effect of the degree of pulmonary arterial systolic pressure on the RVFW strain gradient and on myocardial velocity generation.METHODS:
Peak longitudinal strain and velocity data were collected from three different segments (basal, mid- and apical) of the RVFW in 17 normal individuals and 31 PH patients.RESULTS:
A total of 144 RV wall segments were analyzed. RVFW strain values in individuals without PH were higher in the mid and apical segments than in the basal segment. In contrast, RVFW strain in PH patients was higher in basal segments and diminished toward the apex. In terms of RVFW velocities, both groups showed decremental values from basal to apical segments. Basal and mid-RVFW velocities were significantly lower in PH patients than in individuals without PH.CONCLUSIONS:
PH results in significant alterations of strain and velocity generation that occurs along the RVFW. Of these abnormalities, the reduction in strain from the mid and apical RVFW segments was most predictive of PH. It is important to be aware of these differences in strain generation when studying the effect of PH on the right ventricle. Additional studies are required to determine whether these differences are due to RV remodelling. 相似文献127.
Joshi D Bicer EI Donmez C Hsiung MC Nanda NC Sadat K Sudhakar S Ibrahim H Pandey A Karia N Bhagatwala K Yin WH Jeng-Wei Chung-Yi-Chang Chung YC Tsai SK Dumaswala B Dumaswala K 《Echocardiography (Mount Kisco, N.Y.)》2012,29(5):620-630
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
128.
Nanda NC Samal AK Bakir S Moursi M Thakur AC Aggarwal R Singh S Soto B Cerfolio R McGiffin DC 《Echocardiography (Mount Kisco, N.Y.)》1998,15(4):409-417
We present the transesophageal echocardiographic findings in two adult patients with right-sided aortic arch: one without dissection and the other with traumatic aortic injury (dissection). In both patients, the branching pattern was the left common carotid artery and then the right common carotid artery, followed by the right and left subclavian arteries. The technique for the diagnosis of this anomaly and the identification of adjacent vascular structures using contrast echocardiography is described. Three-dimensional reconstruction of the aortic arch also was performed in both patients. 相似文献
129.
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
130.
Pasquale Palmiero M.D. Maria Maiello M.D. David D. Daly Jr. M.D. Marco Matteo Ciccone M.D. Navin C. Nanda M.D. 《Echocardiography (Mount Kisco, N.Y.)》2012,29(10):1233-1238
Objective: The first goal of our study was to investigate major determinants of aortic stiffness in postmenopausal women using an echocardiographic method to calculate global pulse wave velocity (PWVg) rather than the less accurate carotid–femoral pulse wave velocity (PWVc). The second goal was to relate PWVg to the absolute risk of major cardiovascular (CV) events estimated by CV risk factors. Patients and methods: Two hundred forty‐four consecutive women who presented to our heart station were screened. One hundred twenty‐two were postmenopausal, either natural or surgical, whereas 122 were premenopausal. The mean age of the patients was 54 ± 13 years. Individuals were categorized as current smokers, former smokers, or nonsmokers and hypertensive or not. Hypercholesterolemia and diabetes mellitus were defined. Aortic stiffness was assessed by PWVg measured with pulsed Doppler, the interval between the beginning of QRS complex and the foot of the systolic upstroke in the Doppler spectral envelope was calculated at the aortic valve site and at the right common femoral artery. PWVg was calculated between the aortic valve and right common femoral artery by dividing the straight line distance between the two by the transit time. Results: There was a highly significant statistical difference (P < 0.0012) in PWVg between menstruating women and postmenopausal women. Similarly, this difference in PWVg was also noted among the menstruating population (P < 0.0014) when comparing normotensive women and hypertensive women. In postmenopausal women, PWVg was 6.8 m/sec in normotensive women and 7.56 m/sec in hypertensive women (P < 0.007). Conclusion: PWVg was increased in postmenopausal women compared with menstruating women. Systemic hypertension has an independent, but additive effect on aortic stiffness assessed by PWVg. Our study supports the usefulness of the assessment of aortic stiffness as a marker of CV disease and to identify subjects at risk at an early age. 相似文献