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991.
992.
Pulmonary autograft mitral valve replacement: initial experience with the Ross II procedure 总被引:1,自引:0,他引:1
BACKGROUND: The renewed interest in mitral valve replacement with a pulmonary autograft encouraged us to perform this procedure in selected patients. METHODS AND RESULTS: From August 2000 to February 2002, 10 patients between 30 and 52 years of age with calcific mitral valvular disease underwent the Ross II procedure. Patients were either in New York Heart Association functional class III (7/10) or IV (3/10). Transthoracic echocardiography was done in all the patients to confirm the diagnosis. A pulmonary autograft was used to replace the diseased mitral valve. Intraoperative transesophageal echocardiography confirmed normal functioning of the autograft. There were 2 early deaths. The 8 survivors are in New York Heart Association functional class I with excellent autograft and homograft function at a follow-up of 2-20 months (mean 9 months). CONCLUSIONS: This procedure is a viable option for mitral valve replacement in patients with calcific mitral valve disease. However, the procedure is technically demanding and requires a valve bank. 相似文献
993.
Vikram Kumar Yeragani Arindam Barua Indu Sattiraju Nikhil Mallavarapu 《Cardiovascular Engineering》2003,3(4):141-146
In this study, we evaluated the effectiveness of the statistic, Weighted Coherence in relation to the average or mean coherence in a particular frequency band after cross-spectral analysis. In time domain, correlation coefficient explains the relationship between two variables of interest, and a similar statistic in frequency domain using cross-spectral analysis is referred to as coherence, which is equivalent to the squared correlation coefficient and ranges from zero to unity. In this study, we show that weighted coherence is much more sensitive to various challenges within the same subject and also may be a more sensitive indicator of group differences in different frequency bands. Our data on normal subjects and patients with panic disorder during supine and standing postures during normal breathing, and also at different breathing rates throw new light on the sensitivity of this previously described novel index to quantify coherence between two related time series such as beat-to-beat heart rate and QT interval. 相似文献
994.
Atasu K Nayak Akio Kawamura Richard W Nesto Gershan Davis Jennifer Jarbeau Christopher T Pyne David E Gossman Thomas C Piemonte Nabila Riskalla Manish S Chauhan 《Circulation journal》2006,70(8):1026-1029
BACKGROUND: In-stent restenosis is considered to be a gradual and progressive condition and there is scant data on myocardial infarction (MI) as a clinical presentation. METHODS AND RESULTS: Of 2,462 consecutive patients who underwent percutaneous coronary intervention between June 2001 and December 2002, clinical in-stent restenosis occurred in 212 (8.6%), who were classified into 3 groups: ST elevation MI (STEMI), non-ST elevation MI (NSTEMI) and non-MI. Of the 212 patients presenting with clinical in-stent restenosis, 22 (10.4%) had MI (creatine kinase (CK)>or=2xbaseline with elevated CKMB). The remaining 190 (89.6%) patients had stable angina or evidence of ischemia by stress test without elevation of cardiac enzymes. Median interval between previous intervention and presentation for clinical in-stent restenosis was shorter for patients with MI than for non-MI patients (STEMI, 90 days; NSTEMI, 79 days; non-MI, 125 days; p=0.07). Diffuse in-stent restenosis was more frequent in MI patients than in non-MI patients (72.7% vs 56.3%; p<0.005). Renal failure was more prevalent in patients with MI than in those without MI (31.8% vs 6.3%, p=0.001). Compared with the non-MI group, patients with MI were more likely to have acute coronary syndromes at the time of index procedure (81.8% vs 56.8%, p=0.02). CONCLUSION: Clinical in-stent restenosis can frequently present as MI and such patients are more likely to have an aggressive angiographic pattern of restenosis. Renal failure and acute coronary syndromes at the initial procedure are associated with MI. 相似文献
995.
Mohindra R Pannu HS Mohan B Kumar N Dhooria HS Sehgal A Avasthi G 《Indian heart journal》2004,56(6):668-669
Rheumatic fever is a multi system disease which occurs following infection with group A beta hemolytic streptococcus. It is commonest in the age group of 5-15 years but can occur in adults also. First degree atrioventricular block is a common manifestation of acute rheumatic fever and is included in the Jones criteria but Wenckebacks phenomena and complete heart block are relatively rare manifestations of rheumatic fever. Syncope occurring in acute rheumatic fever is also infrequently reported. We report the case of a 38-year-old male with rheumatic carditis who had advanced atrioventricular block which resulted in syncope and required a temporary pacemaker insertion. 相似文献
996.
Samin K. Sharma Douglas H. Israel Kul Kumar John A. Ambrose 《Catheterization and cardiovascular interventions》1993,30(2):160-161
One of the more difficult and time-consuming diagnostic procedures in the cardiac catheterization laboratory is retrograde crossing of the severely stenotic aortic valve. Whereas patients with advanced aortic stenosis tend to be complicated and elderly, lengthy procedures can lead to a higher incidence of thrombo-embolic and vascular complications and relatively greater procedural blood loss. This report concerns the use of the Terumo Glidewire to facilitate passage through stenotic and tortuous peripheral arteries. © 1993 Wiiey-Liss, Inc. 相似文献
997.
Increased AT2R protein expression but not increased apoptosis during cardioprotection induced by AT1R blockade 总被引:3,自引:0,他引:3
Moudgil R Musat-Marcu S Xu Y Kumar D Jugdutt BI 《The Canadian journal of cardiology》2002,18(8):873-883
BACKGROUND: The angiotensin II type 2 receptor (AT2R) is considered to be antigrowth and to mediate apoptosis in several cell types. Whether AT2R upregulation, associated with angiotensin II type 1 receptor (AT1R) blockade and cardioprotection after ischemia-reperfusion (IR), might not result in increased cardiomyocyte (CM) apoptosis has not been documented. OBJECTIVES: To determine whether increased AT2R protein expression, during AT1R blockade after acute IR, is associated with no increase in CM apoptosis. MATERIALS AND METHODS: The recovery of left ventricular (LV) mechanical function after acute IR (30 min of ischemia, 40 min of reperfusion) was measured in isolated Langendorff rat hearts following pretreatment with the AT1R antagonist candesartan (CN) (CN 10 nmol/L) for 40 min before ischemia. The authors established with an initial dose-response curve using escalating concentrations of CN that 10 nmol/L abrogated vasoconstriction induced by angiotensin II (0.1 mmol/L). AT1R and AT2R protein expression (Western immunoblot), CM apoptosis (terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end-labelling assay and nuclear morphology) and apoptotic markers (Bax, Bcl-2, caspase-3, p53) were assessed in LV tissue. RESULTS: Compared with IR controls, CN improved peak systolic pressure, LV developed pressure and positive dp/dt, and increased AT2R (not AT1R) protein, but did not change the level of apoptosis or the expression of Bax, Bcl-2, caspase-3 or p53. CN also increased AT2R protein after ischemia alone but did not change CM apoptosis or expression of the markers. CONCLUSIONS: Increased AT2R protein expression during AT1R blockade after IR in the isolated Langendorff rat heart is associated with cardioprotection but no increase in CM apoptosis. 相似文献
998.
V.G. Rao M. Muniyandi J. Bhat R. Yadav R. Sharma 《The Indian journal of tuberculosis》2018,65(1):8-14
Background
Tuberculosis (TB) remains a major public health problem in resource-poor countries including India. Scientific knowledge is used to guide policy and practice. There is however, a limited, systematically collected data required for guiding the scale-up of interventions particularly amongst vulnerable populations including tribal groups in the country. In view of this, a systematic review of the TB research studies carried out in tribal areas of different parts of the country was undertaken.Objective
To undertake a systematic review of the TB research studies carried out in tribal areas of India between 1996 and 2016.Methods
A systematic review of English articles published between 1996 and 2016 on any aspect of TB was done through internet searches using Literature search EndNote programme. The words used for searching were tuberculosis, India, tribal, indigenous, disadvantaged, adivasi. The most common topics classified as annual risk of tuberculosis infection (ARTI), prevalence of TB, laboratory studies, clinical symptoms of TB, risk factors for TB, knowledge attitude practice, community Directly Observed Treatment (DOT) providers, performance of Revised National Tuberculosis Control Programme (RNTCP), and drug resistant TB. Classification was also done on the basis of the type of tribe studied and place of study conducted. A total of 47 studies identified through the search were included in the review.Results
Of the 47 studies reviewed, 12 were on TB prevalence, 7 were laboratory studies, four on ARTI and 5 on performance of RNTCP in tribal areas. Among these, majority (23 studies) of the tribal studies did not mention the type of tribe. Ten studies were conducted among Saharia, a particularly vulnerable tribal group in the Indian state of Madhya Pradesh mainly by the National Institute for Research on Tribal Health, five were among the mixed tribes and very few on other tribes.Conclusion
The systematic review indicates that the research studies on TB among tribal population are very few. There is a need to invest and encourage researcher to work on the research plans for the control of TB in tribal areas. 相似文献999.
Cytomegalovirus (CMV) can be classified into 4 glycoprotein B (gB) genotypes, on the basis of sequence variation in the UL55 gene. We assessed the effect that CMV gB genotype has on virologic and clinical response to therapy, in 50 solid-organ-transplant recipients with CMV disease. CMV loads were determined at regular intervals after the start of therapy. Genotype results were correlated with CMV-load kinetics in response to therapy with ganciclovir. At the onset of treatment, the distribution of CMV gB genotypes was as follows: gB1, 19/50 (38%); gB2, 9/50 (18%); gB3, 12/50 (24%); gB4, 2/50 (4%); and mixed-genotype infection, 8/50 (16%). Between viral genotype groups, time to clearance of CMV, failure to clear CMV, and calculated CMV-load half-life after the start of therapy were not significantly different. The CMV gB genotype did not affect the rate of disease recurrence or occurrence of tissue-invasive disease. It appears that the gB genotype, which causes CMV disease, does not significantly influence CMV-load kinetics or clinical response to therapy. 相似文献
1000.