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51.
Secondary amyloidosis (SA) affects cardiac texture and function by interstitial fibrosis. Doppler tissue imaging (DTI) may quantify heart function through the assessment of myocardial velocities. Echocardiographic findings of early cardiac amyloidosis (CA) without heart failure (HF) caused by SA were determined both by standard methods and DTI. It was then determined whether DTI is superior to conventional echocardiography in documenting early CA due to SA. Twenty-five patients with SA who had CA without HF (group 1) were compared with 25 healthy control subjects (group 2). After standard echocardiography, systolic (s), early (e) and late diastolic (a) velocities of interventricular septum, anterolateral, and anterior and inferior walls were measured from mitral annulus by DTI. The averages were called (smean), (emean), and (amean), respectively. Fractional shortening (FS) and ejection fraction (EF) values of groups 1 and 2 were similar. Standard Doppler echocardiographic values were not typical for a specific diastolic abnormality. The (smean) and (emean) for group 1 were lower but (amean) was higher compared with group 2 (all P < .05). The group 1 (emean/amean) was lower (P < .0001) and (E/emean) was higher (P=.003) than in group 2 (both P < .05). (E/emean) and (E/elateral wall) ratios were positively correlated (r=0.74, P < .05). In patients with early CA due to SA without HF, by DTI, (smean) and (emean) velocities decrease and (amean) velocity increases. These may be markers of subclinical CA of SA when standard echocardiography is not informative. (E/emean) ratio may be an alternative index to (E/elateral wall).  相似文献   
52.
AIMS: Beta-blockers (BBs) have been shown to improve survival and reduce the risk of re-infarction in patients following myocardial infarction. There are conflicting data about the effects of BB therapy on cardiac biomarkers after percutaneous coronary interventions (PCIs). The aim of the study was to investigate the effects of BB use on cardiac troponin-I (cTnI) levels in patients who had undergone elective PCI. METHODS AND RESULTS: In this prospective study, 287 patients with coronary artery disease were included. Patients were randomized either to BB or control groups prior to the intervention. Blood samples for cTnI were obtained before and at 6, 24, and 36 h after the procedure. Of the 287 patients included, 143 received metoprolol succinate 100 mg/day, and 144 received no BB and served as the control group. Baseline clinical characteristics of both groups, except for history of coronary artery bypass graft surgery, were similar. We observed no significant difference in the elevation of cTnI levels between the two groups after PCI (BB group, 17 patients, 11.9%; control group, 10 patients, 6.9%; P=0.2). CONCLUSION: Metoprolol succinate therapy seems to have no cardioprotective effect in limiting troponin-I rise after PCI.  相似文献   
53.
BACKGROUND: Recently, several temporary multisite pacing methods have been developed for prevention of postoperative atrial fibrillation (AF). HYPOTHESIS: In this study, we evaluated the effect of triple-site temporary triggered pacing in the AAT mode on the development of AF in patients undergoing coronary artery bypass graft (CABG) at high risk for developing postoperative AF. METHODS: A total of 70 patients undergoing CABG were randomly assigned either to pacing group (study group, n = 35 patients) or to no pacing group (control group, n = 35 patients). The external pacemaker was programmed to pace at the atrial triggered mode at a lower rate of 40 beats/min for 4 days. RESULTS: Atrial fibrillation, defined as lasting > 30 s, occurred in 4 patients (11.4%) in the study group and in 16 patients (45.7%) in the control group (p = 0.003). Sustained AF, defined as AF lasting > 10 min, also was observed less frequently in the study group than in the control group (11.6 vs. 37.1%, p = 0.024). Triple-site triggered atrial pacing was observed to reduce the incidence of AF by 75% and the incidence of sustained AF by 69%. CONCLUSIONS: We believe that multiple-site temporary pacing in the triggered mode is an effective way of preventing postoperative AF. This technique may be used especially in patients at high risk of developing AF.  相似文献   
54.
Basal septal hypertrophy (BSH), a cause of left ventricular outflow tract (LVOT) obstruction, is thought to occur by increased ventricular dynamics. The aim of the study was to evaluate the effect of pharmacologic stress on LVOT gradients in a group of hypertensive patients with BSH. Dobutamine stress was used in 24 hypertensive patients (mean age 56 +/-8 years; 11 women) with BSH and 20 normal controls (mean age 54 +/-9 years; 7 women). Ejection fraction and myocardial mass, basal septal dimension, and LVOT diameter were measured with 2-dimensional echocardiography. LVOT velocities and transmitral velocities before and at peak dobutamine infusion were determined by continuous wave Doppler and pulsed Doppler, respectively. There were no differences in mean ejection fraction and myocardial mass between BSH patients (58 +/-3%, 204 +/-24 g) and normals (56 +/-4%, 201 +/-32 g). The basal septum was thicker in patients (1.55 +/-0.2 cm) than in normals (1.03 +/-0.1 cm, p<0.001). Maximum LVOT velocities were similar in BSH (1.2 +/-0.4 m/sec) and normals (1.1 +/-0.2 m/sec) at rest. At peak stress, maximum LVOT velocities were higher in BSH (3.3 +/-0.6 m/sec) than normals (1.7 +/-0.4 m/sec, p<0.001). LV rate-pressure product at peak stress was higher in BSH (23,326 +/-4,388) than normals (17,592 +/-2,409, p<0.001). LV isovolumetric relaxation time was prolonged, and the E/A ratio was decreased in the patients at rest (130 +/-14 msec and 0.72 +/-0.18, respectively, p<0.001). At peak stress, diastolic function did not significantly change in two groups. The correlations between LVOT velocity change by stress and mean LVOT diameter (r=-0.668, p<0.001) and mean BS thickness (r=0.610; p<0.001) were significant in the whole group. High velocities appeared on LVOT at peak pharmacologic stress in the hypertensive patients with BSH compared with control group. This suggests dynamic ventricular ejection by stress may contribute to hypertrophy of the basal segment, which is the closest part of septum to increased afterload.  相似文献   
55.
56.
Background: Adenosine is widely used for the diagnosis and the termination of supraventricular arrhythmias. There are many case reports and few series about the proarrhythmic potential of adenosine. We sought to evaluate the proarrhythmic potential of adenosine used to terminate the supraventricular arrhythmias. Methods: The records of all patients that received adenosine for the termination of supraventricular tachycardia were reviewed retrospectively and those with a continuous electrocardiographic (ECG) recording during adenosine administration were included to the study. Results: Our search identified 52 supraventricular episodes of 46 patients with a continuous ECG recording during adenosine administration. Following adenosine administration, premature ventricular contraction (PVC) or ventricular tachycardia (VT) developed in 22 (47.8%) patients and in 26 (50%) tachycardia episodes. No patient had a sustained VT. Nonsustained VT developed in eight (17.4%) patients. All VT episodes were polymorphic, short, and self‐terminating. When the basal and demographic properties of patients with PVC or VT and those without PVT or VT were compared, there was no significant difference. Conclusions: Adenosine is a quite safe and effective drug for the termination of narrow QRS complex tachycardia but it often induces nonsustained VT or PVC that are clinically insignificant in the absence of other accompanying heart disease.  相似文献   
57.
AIM: To compare interferon monotherapy with combination treatment using interferon and lamivudine in children with chronic hepatitis B. METHODS: Data from 65 children who had received either interferon-alpha (5 MU/m2 subcutaneous thrice a week for 6 months; n=35; Group 1) or this dose of interferon-alpha for 6 months with oral lamivudine for one year (4 mg/Kg/day, maximum 100 mg/day; n=30; Group 2) were analyzed retrospectively. Complete response was defined as ALT normalization, HBeAg/anti-HBe seroconversion and HBV DNA clearance. RESULTS: ALT normalization rates were similar in Groups 1 and 2 at the end of interferon treatment (13 [38%] and 16 [52%], respectively), at 12 months (19 [56%] and 18 [58%]) and at 24 months (24 [71%] and 23 [74%]). HBV DNA clearance was more frequently observed at 6 months in Group 2 than in Group 1 (19 [63%] versus 7 [20%]; p=0.01), but not at 12 months (19 [63%] versus 17 [49%]) or at 24 months (20 [67%] versus 21 [60%]). Rate of HBeAg/anti-HBe seroconversion was higher in Group 2 at 12 months (18 [60%] versus 11 [31%]; p< 0.05). Rate of complete response was similar in Groups 1 and 2 at 6 months (5 [14%] and 10 [33%], respectively), 12 months (14 [40%] and 17 [57%]) and 24 months (20 [57%] and 19 [63%]). CONCLUSION: Although lamivudine and interferon combination achieved higher initial rates of HBV DNA loss and HBeAg/anti-HBe seroconversion than interferon alone, the final response rates were similar with the two treatments. The combination treatment is therefore not indicated for chronic hepatitis B in children.  相似文献   
58.

Background  

Treatment of a number of complications that occur after abdominal surgeries may require that Urgent Abdominal Re-explorations (UARs), the life-saving and obligatory operations, are performed. The objectives of this study were to evaluate the reasons for performing UARs, outcomes of relaparotomies (RLs) and factors that affect mortality.  相似文献   
59.
Cor triatriatum dexter is a very rare congenital abnormality in which the right atrium is divided into two chambers by a membrane. In this abnormality, there is a high incidence of associated congenital abnormalities, particularly of the right heart. In this case study, a 67-year-old man with Ebstein's anomaly, atrial septal defect, and cor triatriatum dexter is presented and echocardiography is discussed as a noninvasive diagnostic tool.  相似文献   
60.
Extraskeletal Ewing's sarcoma is an uncommon disease that predominantly involves the soft tissues of the trunk or the extremities. This article presents a patient with multifocal intrathoracic mass lesions involving the mediastinum and the lingula associated with mediastinal shift, eventually diagnosed as extraskeletal Ewing's sarcoma.  相似文献   
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