262 research outputs found

    Biventricular Pacing in Heart Failure: back to Basic in the pathophysiology of left bundle branch block to reduce the number of nonresponders

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    Cardiac resynchronization therapy is a novel nonpharmacologic approach to treating patients who have advanced heart failure with left bundle branch block (LBBB). Such a therapy is based on the original theory that synchronous biventricular pacing is able to reduce the interventricular delay caused by LBBB in patients with heart failure. Although there is convincing evidence that biventricular pacing increases the left ventricular ejection fraction, decreases mitral regurgitation, and improves symptoms caused by heart failure, the percentage of nonresponders to such therapy has been described as high as about one third of patients with heart failure having LBBB. Factors responsible for this relatively high prevalence are reviewed, the most important of them probably being left intraventricular dyssynchrony, which can persist after biventricular pacing, notwithstanding right and left interventricular resynchronization. Such a dyssynchrony, as evaluated by tissue Doppler imaging, may be because of the discordance between the site of the left ventricular pacing and the site of the left ventricular delay. Therefore, to characterize the pathophysiologic pattern of LBBB, the investigators suggest an assessment of the electromechanical dysfunction with a noninvasive reliable technique, such as tissue Doppler imaging, which can be repeated after biventricular pacing

    Doppler myocardial imaging to evaluate the effectivenes of pacing sites in patients receving biventricular pacing

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    OBJECTIVES: The goal of this study was to compare the efficacy of biventricular pacing (BIV) at the most delayed wall of the left ventricle (LV) and at other LV walls. BACKGROUND: Biventricular pacing could provide additional benefit when it is applied at the most delayed site. METHODS: In 31 patients with advanced nonischemic heart failure, the activation delay was defined, in blind before BIV, by regional noninvasive Tissue Doppler Imaging as the time interval between the end of the A-wave (C point) and the beginning of the E-wave (O point) from the basal level of each wall. The left pacing site was considered concordant with the most delayed site when the lead was inserted at the wall with the greatest regional interval between C and O points (CO(R)). After BIV, patients were divided into group A (13/31) (i.e., paced at the most delayed site) and group B (18/31) (i.e., paced at any other site). RESULTS: After BIV, in all patients LV end-diastolic (LVEDV) and end-systolic (LVESV) volumes decreased (p = 0.025 and 0.001), LV ejection fraction (LVEF) increased (p = 0.002), QRS narrowed (p = 0.000), New York Heart Association class decreased (p = 0.006), 6-min walked distance (WD) increased (p = 0.046), the interval between closure and opening of mitral valve (CO) and isovolumic contraction time (ICT) decreased (p = 0.001 and 0.000), diastolic time (EA) and Q-P(2) interval increased (p = 0.003 and 0.000), while Q-A(2) interval and mean performance index (MPI) did not change. Group A showed greater improvement over group B in LVESV (p = 0.04), LVEF (p = 0.04), bicycle stress testing work (p = 0.03) and time (p = 0.08) capacity, CO (p = 0.04) and ICT (p = 0.02). CONCLUSIONS: After BIV, LV performance improved significantly in all patients; however, the greatest improvement was found in patients paced at the most delayed site

    The stability of lidocaine and epinephrine solutions exposed to electric current and comparative administration rates of the two drugs into pig bladder wall.

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    Intravesical electromotive administration of local anesthetics is clinically successful but electrochemistry, cost and effectiveness limit the choice of drugs to diluted lidocaine HCl 4% mixed with epinephrine. These studies address the stability of lidocaine and epinephrine both over time and when exposed to electric current, i.e. transport rates with passive diffusion and electromotive administration. The drug mixture used was 50 ml lidocaine 4%, 50 ml H2O and 1 ml epinephrine 1/1000. For stability, the solution was placed either in bowls for 7 days or in a two chamber cell with the donor compartment (drugs) separated from the receptor compartment (NaCl solution) by a viable pig bladder wall. This was subjected to 30 mA for 45 min. Stability was measured with mass spectrometry. The cell was also used to determine transport rates with passive diffusion and currents of 20 mA and 30 mA, over 20, 30 and 45 min. Drug measurements in both compartments and bladder were made with HPLC. Lidocaine remained stable throughout the 7 days, epinephrine on day 1 only and both drugs were stable with 30 mA for 45 min. Comparing 20 mA and 30 mA with passive diffusion, there were significant differences in 6/6 donor compartment lidocaine levels, 4/6 receptor compartment levels and 6/6 bladder tissue levels and also in 6/6 epinephrine donor levels and 6/6 tissue levels. The combination lidocaine and epinephrine remains stable for 1 day and when exposed to 30 mA for 45 min. Electric current accelerates the transport of lidocaine and epinephrine

    Intravesical oxybutynin: mode of action assessed by passive diffusion and electromotive administration with pharmacokinetics of oxybutynin and N-desethyl oxybutynin.

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    PURPOSE: A proportion of patients with detrusor hyperreflexia who are unresponsive to oral oxybutynin often benefit from intravesical oxybutynin instillation. To our knowledge the precise mode of action of this method is obscure. MATERIALS AND METHODS: In 12 patients with detrusor hyperreflexia who were previously unresponsive to oral and intravesical passive diffusion of 5 mg. oxybutynin we administered 5 mg. oxybutynin orally as well as increased doses of 15 mg. oxybutynin intravesically with passive diffusion and with 15 mA. associated electric current. Each administration mode per patient was associated with an 8-hour urodynamic monitoring session during which oxybutynin and N-desethyl oxybutynin plasma levels, and intravesical oxybutynin uptake were measured. RESULTS: A dose of 5 mg. oxybutynin orally induced no urodynamic improvement with an area under the plasma concentration time curve of combined N-desethyl oxybutynin plus oxybutynin of 16,297 ng./8 hours and an area under the curve ratio of N-desethyl oxybutynin-to-oxybutynin of 11:1. Passive diffusion oxybutynin resulted in 12 mg. oxybutynin intravesical uptake and significant improvement in 3 of 8 urodynamic measurements, although the area under the curve of combined N-desethyl oxybutynin plus oxybutynin was only 2,123 ng./8 hours and the N-desethyl oxybutynin-to-oxybutynin ratio was 1.1:1.0. Electromotive administration of oxybutynin resulted in almost complete intravesical uptake of the 15 mg. dose, significant improvement in all 8 urodynamic measurements and an increased oxybutynin level versus oral and passive diffusion, although the area under the curve of combined N-desethyl oxybutynin plus oxybutynin was 4,574 ng./8 hours and the N-desethyl oxybutynin-to-oxybutynin ratio was inverted at 1.0:1.4. The oral dose of 5 mg. oxybutynin caused anticholinergic side effects in 8 of the 12 patients. Neither intravesical passive diffusion nor electromotive administration caused side effects with an uptake of 12 and 15 mg., respectively. CONCLUSIONS: A large proportion of intravesical oxybutynin is sequestered, probably in the urothelium. Intravesical oxybutynin administration confers therapeutic benefits via localized direct action within the bladder wall. Comment in Intravesical treatment of bladder dysfunction. [J Urol. 2001

    Intravesical electromotive mitomycin C versus passive transport mitomycin C for high risk superficial bladder cancer: a prospective randomized study.

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    PURPOSE: In laboratory studies electromotive mitomycin C (MMC) demonstrated markedly increased transport rates compared with passive transport. We performed a prospective study in patients with high risk superficial bladder cancer to assess the efficacy of intravesical electromotive vs passive MMC using bacillus Calmette-Guerin (BCG) as a comparative treatment. MATERIALS AND METHODS: Following transurethral resection and multiple biopsies 108 patients with multifocal Tis, including 98 with T1 tumors, were randomized into 3 equal groups of 36 each who underwent 40 mg electromotive MMC instillation with 20 mA electric current for 30 minutes, 40 mg passive MMC with a dwell time of 60 minutes or 81 mg BCG with a dwell time of 120 minutes. Patients were scheduled for an initial 6 weekly treatments, a further 6 weekly treatments for nonresponders and a followup 10 monthly treatments for responders. Primary end points were the complete response rate at 3 and 6 months. MMC pharmacokinetics were assessed. RESULTS: The complete response for electromotive vs passive MMC at 3 and 6 months was 53% versus 28% (p = 0.036) and 58% versus 31% (p = 0.012). For BCG the responses were 56% and 64%. Median time to recurrence was 35 vs 19.5 months (p = 0.013) and for BCG it was 26 months. Peak plasma MMC was significantly higher following electromotive MMC than after MMC (43 vs 8 ng/ml), consistent with bladder content absorption. CONCLUSIONS: Intravesical electromotive administration increases bladder uptake of MMC, resulting in an improved response rate in cases of high risk superficial bladder cancer

    Hyperbaric oxygen therapy for painful bladder syndrome/interstitial cystitis resistant to conventional treatments: long-term results of a case series in Japan

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    <p>Abstract</p> <p>Background</p> <p>There is no confirmed strategy for treating painful bladder syndrome/interstitial cystitis (PBS/IC) with unclear etiology. Therefore, a pilot study was carried out to evaluate the efficacy and safety of hyperbaric oxygen (HBO) therapy in treatment-resistant PBS/IC patients.</p> <p>Methods</p> <p>HBO treatment (2.0 ATA for 60 minutes/day × 5 days/week for 2 or 4 weeks) was performed on 11 patients with severe symptoms that had not been improved by previous therapy regimens between December 2004 and July 2009.</p> <p>Results</p> <p>Seven of the 11 patients demonstrated persistent improvement in symptoms during the 12 months after HBO treatment. These responders demonstrated a decrease in the pelvic pain scale and urgency scale from 7.7 ± 1.0 and, 6.6 ± 0.9 to 3.4 ± 2.5 and 4.3 ± 2.4 after 12 months, respectively (p < 0.05). The total score of the interstitial cystitis symptom index and 24-hour urinary frequency demonstrated a significant sustained decrease from the baseline. Two responders, who received an additional course of HBO 12 and 13 months after initial treatment, respectively, did not suffer impairment for more than two years. There was one case of transient eustachian tube dysfunction and three cases of reversible exudative otitis media as a consequence of HBO treatment.</p> <p>Conclusions</p> <p>HBO is a potent treatment for PBS/IC patients resistant to conventional therapy. It was well tolerated and provided maintained amelioration of pain, urgency and urinary frequency for at least 12 months.</p

    Treatment success for overactive bladder with urinary urge incontinence refractory to oral antimuscarinics: a review of published evidence

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    <p>Abstract</p> <p>Background</p> <p>Treatment options for overactive bladder (OAB) with urinary urge incontinence (UUI) refractory to oral antimuscarinics include: botulinum toxin type A (BoNTA), sacral neuromodulation (SNM), and augmentation cystoplasty (AC). A standard treatment success metric that can be used in both clinical and economic evaluations of the above interventions has not emerged. Our objective was to conduct a literature review and synthesis of published measures of treatment success for OAB with UUI interventions and to identify a treatment success outcome.</p> <p>Methods</p> <p>We performed a literature review of primary studies that used a definition of treatment success in the OAB with UUI population receiving BoNTA, SNM, or AC. The recommended success outcome was compared to generic and disease-specific health-related quality-of-life (HRQoL) measures using data from a BoNTA treatment study of neurogenic incontinent patients.</p> <p>Results</p> <p>Across all interventions, success outcomes included: complete continence (n = 23, 44%), ≥ 50% improvement in incontinence episodes (n = 16, 31%), and subjective improvement (n = 13, 25%). We recommend the OAB with UUI treatment success outcome of ≥ 50% improvement in incontinence episodes from baseline. Using data from a neurogenic BoNTA treatment study, the average change in the Incontinence Quality of Life questionnaire was 8.8 (95% CI: -4.7, 22.3) higher for those that succeeded (N = 25) versus those that failed (N = 26). The average change in the SF-6D preference score was 0.07 (95% CI: 0.02, 0.12) higher for those that succeeded versus those that failed.</p> <p>Conclusion</p> <p>A treatment success definition that encompasses the many components of underlying OAB with UUI symptoms is currently not practical as a consequence of difficulties in measuring urgency. The treatment success outcome of ≥ 50% improvement in incontinence episodes was associated with a clinically meaningful improvement in disease-specific HRQoL for those with neurogenic OAB with UUI. The recommended success definition is less restrictive than a measure such as complete continence but includes patients who are satisfied with treatment and experience meaningful improvement in symptoms. A standardized measure of treatment success will be useful in clinical and health economic applications.</p
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