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81.
82.
Purpose: CAN-SAVE R is a Canadian multicenter study that compares the effects of a new pacing mode algorithm designed to minimize right ventricular (V) pacing versus DDD mode with a long atrioventricular (AV) delay in a general population of pacemaker (PM) recipients .
Study Participants: Patients with permanent atrial fibrillation (AF) or high-degree AV block (AVB) were excluded. We present preliminary data collected in 208 patients (mean age = 71 ± 11 years, 68% men), for the 2-month baseline period during which all PM were programmed in the new pacing mode. The pacing indications were sinus node disease (SND) without AVB in 39%, AVB without SND in 30%, SND and AVB in 16%, and miscellaneous in 15% of patients.
Results: The mean percent V pacing in the overall population was 9.5 ± 23.8% (range = 0–100%, median <1%), ranging between 0.5 ± 1.5% (median = 0) in patients without AVB and 18.7 ± 31.2% in patients (median = 1) with AVB. Adverse events potentially related to the new pacing mode were observed in two patients with AVB.
Conclusions: A new pacing mode was effective and safe in a general population of PM recipients without permanent AVB and was associated with an overall <1% median V pacing. CAN-SAVE R will compare the long-term effects of the new pacing mode with DDD with a long AV delay on clinical outcomes and cardiac function.  相似文献   
83.
PURPOSE: We investigate the safety and efficacy of suprapubic transvesical prostatectomy, and the change in bladder wall thickness after surgery. MATERIALS AND METHODS: We conducted a prospective 1 center study of 32 consecutive patients who underwent transvesical prostatectomy from December 1996 to March 1997 for benign prostatic hyperplasia with large prostate volume, who were followed for 1 year. Pressure flow study and transrectal sonography were performed at baseline and repeated at 6 months. Bladder wall thickness was measured at baseline and regular intervals postoperatively. A morbidity questionnaire was completed during the first 6 weeks after surgery. RESULTS: An average of 63 gm. prostate adenoma were enucleated at surgery. An indwelling catheter was required for an average plus or minus standard deviation of 5.4 +/- 2.6 days after treatment. The International Prostate Symptom Score decreased from 19.9 +/- 4.4 to 1.5 +/- 2.7 and the quality of life score decreased from 4.9 +/- 1.0 to 0.2 +/- 0.4 at year 1, respectively. Maximum flow rate improved from 9.1 +/- 5.3 to 29.0 +/- 8.9 ml. per second. Residual urine decreased from 128 +/- 113 to 8 +/- 18 ml. Before surgery 30 patients had obstruction and 2 were in the equivocal zone of the International Continence Society nomogram. At 6 months after prostatectomy 30 patients did not have obstruction, and 2 who were subsequently operated on for bladder neck sclerosis were equivocal and had obstruction, respectively. No patient had significant postoperative bleeding and no heterologous blood transfusions were required. There were 4 men who had urinary tract infection and 1 who had wound infection. A slight decrease in erectile function was observed 6 weeks postoperatively, and no change in patient libido and quality of sex life was reported. The total complication rate was 31.3%. The bladder was unstable in 7 men before and 3 after surgery. A significant decrease in bladder wall thickness was observed from 5.2 +/- 0.7 at baseline to 2.9 +/- 0.9 mm. at year 1 postoperatively. CONCLUSIONS: Our study confirms the excellent clinical outcome of transvesical prostatectomy, and rapid improvement of most subjective and objective parameters during the 4 weeks after surgery. Bladder hypertrophy appears to be significantly reduced after prostate surgery. The urodynamic results in patients who underwent open surgery probably represent the maximum obtainable relief of obstruction and should be considered the reference standard to which all other treatments, including transurethral resection, should aspire.  相似文献   
84.
BackgroundMultiple different pathophysiologic processes can contribute to worsening renal function (WRF) in acute heart failure.Methods and ResultsWe retrospectively analyzed 787 patients with acute heart failure for the relationship between changes in serum creatinine and biomarkers including brain natriuretic peptide, high sensitivity cardiac troponin I, galectin 3, serum neutrophil gelatinase-associated lipocalin, and urine neutrophil gelatinase-associated lipocalin. WRF was defined as an increase of greater than or equal to 0.3 mg/dL or 50% in creatinine within first 5 days of hospitalization. WRF was observed in 25% of patients. Changes in biomarkers and creatinine were poorly correlated (r ≤ 0.21) and no biomarker predicted WRF better than creatinine. In the multivariable Cox analysis, brain natriuretic peptide and high sensitivity cardiac troponin I, but not WRF, were significantly associated with the 1-year composite of death or heart failure hospitalization. WRF with an increasing urine neutrophil gelatinase-associated lipocalin predicted an increased risk of heart failure hospitalization.ConclusionsBiomarkers were not able to predict WRF better than creatinine. The 1-year outcomes were associated with biomarkers of cardiac stress and injury but not with WRF, whereas a kidney injury biomarker may prognosticate WRF for heart failure hospitalization.  相似文献   
85.
The role of brain catecholamine (CA) activity in the neuroendocrine regulation of the GnRH-LH system in polycystic ovary syndrome (PCO) was investigated by high-performance liquid chromatography (HPLC) with electrochemical detector. We measured urinary dopamine (DA), noradrenaline (NA), adrenaline (A), vanillylmandelic acid (VMA), homovanillic acid (HVA), 3,4-dihydroxyphenylacetic acid (DOPAC) and total 3-methoxy-4-hydroxyphenylglycol (MHPG) levels in a group of 12 women with PCO before and during peripheral dopa-decarboxylase blockade, by carbidopa. HVA and DOPAC concentrations were significantly lower (P less than 0.001 and P less than 0.005, respectively) in PCO patients compared with twelve control subjects in early follicular phase, whereas total MHPG concentrations and MHPG/VMA ratio were significantly higher (P less than 0.005) in PCO patients. Moreover, HVA and DOPAC concentrations in PCO patients were similar to those of the control subjects in preovulatory phase, while MHPG concentrations remained higher in PCO patients (P less than 0.01). DA, NA, A and VMA concentrations were similar to those of control subjects in both phases of the cycle. During carbidopa administration the concentrations of all urinary CAs and metabolites were unchanged, except those of DA which dropped markedly (P less than 0.001). These data suggest that (1) an altered central catecholamine metabolism consisting of DA deficiency and NA excess is present in PCO, and (2) the site of DA deficiency may be located in the hypothalamus.  相似文献   
86.
87.
Brain metabolism and blood flow during sleep   总被引:3,自引:1,他引:2  
  相似文献   
88.
This study evaluated the clinical usefulness of biplanar transesophageal echocardiography (TEE) in suspected arrhythmogenic right ventricular dysplasia (ARVD). Seven symptomatic subjects (3 male and 4 female: ages 18–64 years, mean 45) with clinical features of ARVD (typical ventricular arrhythmias) underwent comprehensive noninvasive assessment including transthoracic echocardiography (TTE), nuclear magnetic resonance (NMR), and TEE. Other systemic and cardiac diseases were reasonably excluded. TEE identified a significant right ventricular regional alteration in one subject with negative TTE and NMR, and nonsignificant abnormalities in two subjects with negative or no TTE and positive NMR. TEE confirmed the pathological findings detected by TTE in the four remaining patients and visualized several more abnormalities that approximately corresponded to NMR results. On the basis of these initial results, biplanar TEE appears to be comparable to NMR in the assessment of ARVD and a promising technique in identifying ARVD morphological alterations.  相似文献   
89.
Sudden Death Due to Atrial Fibrillation in Hypertrophic Cardiomyopathy:   总被引:1,自引:0,他引:1  
FAVALE, S., et al .: Sudden Death Due to Atrial Fibrillation in Hypertrophic Cardiomyopathy: A Predictable Event in a Young Patient. This case refers to a 39-year-old woman with hypertrophic cardiomyopathy (HCM) and family history of sudden death (SD). In 1985, high rate atrial stimulation induced VF. In 1996 an ICD was implanted and she remained without arrhythmic events until November 2000 when the device reported one episode of atrial fibrillation degenerating into VF and terminated by the ICD. The VF induction mechanism recorded by the ICD was similar to that observed in 1985. The high incidence of atrial tachyarrhythmias in HCM renders cases like this at higher risk of SD. The predictive role of incremental atrial stimulation merits highlighting in future studies. (PACE 2003; 26[Pt. I]:637–639)  相似文献   
90.
Flecainide Test in Brugada Syndrome: A Reproducible but Risky Tool   总被引:5,自引:0,他引:5  
GASPARINI, M., et al .: Flecainide Test in Brugada Syndrome: A Reproducible but Risky Tool. The flecainide test is widely used in Brugada syndrome. However, its reproducibility and safety remain ill-defined. This study included 22 patients (18 men, mean age 34 years). Mutations in the SCN5A gene were found in eight patients. Two patients had aborted sudden cardiac death, 8 had syncope/presyncope, and 12 were asymptomatic. The ECG was diagnostic in 19 patients and suggestive in 3. At baseline, 21 of 22 patients underwent a flecainide test (2 mg/kg IV bolus over 10 minutes). In 21 of 21 patients the test was diagnostic or amplified the typical ECG pattern. At the end of drug infusion, sustained VT lasting 7–10 minutes developed in two patients. A second flecainide test was performed within 2 months in 20 patients. The test was not repeated in the two patients with prior development of VT. The flecainide test was diagnostic in 20 of 20 patients. Sustained VT occurred in one patient and recurrent VF in another. The reproducibility of the flecainide test was 100%. In 4 (18%) of 22 patients major VAs were documented after the end of flecainide infusion. VA occurred in 3 (43%) of 7 patients with, versus 1 (7%) 15 without SCN5A gene mutation (P < 0.05). No diagnostic ECG changes or arrhythmias developed in 25 control patients without structural heart disease who underwent the same study protocol. This study shows a high flecainide reproducibility, supporting its diagnostic value in Brugada syndrome. However, the occurrence of major VA, significantly higher in patients with documented SCN5A gene mutation, including in asymptomatic patients, mandates the performance under appropriate medical supervision. Whether a slower rate of drug infusion can lower the risk of VA induction, while maintaining the sensitivity of the test should be explored. (PACE 2003; 26[Pt. II]:338–341)  相似文献   
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