Evaluation of a video based health education strategy to improve sexually transmitted disease partner notification in South Africa

OBJECTIVES

To evaluate the feasibility and impact of a health education intervention promoting partner notification for sexually transmitted diseases (STDs).

METHODS

The research setting was a busy public health clinic in a rural district in KwaZulu Natal, South Africa. A before/after quantitative study design was used to measure the effect of an audiovisual presentation of a compelling love drama, posters, and pamphlets. Measures collected from all consenting STD index patients during a 6 week pre-intervention (control) phase were compared with those collected during a 6 week intervention phase. A qualitative evaluation assessed whether the intervention accurately portrayed the intended educational messages.

RESULTS

150 index patients (55% female) were interviewed in the control phase and 185 index patients (64% female) in the intervention phase. The intervention phase showed improvements on several measures of self efficacy about notifying casual partners, such as a belief among index patients that a greater proportion of their casual partners would see the importance of seeking treatment as a result of their notification interaction. The rate of contact cards returned per index patient was 0.27 in the intervention phase, compared with 0.20 in the control phase (95% CI for the rate difference: -0.05, 0.17). The qualitative research found that the intervention was thoroughly enjoyed by patients and clinicians, but a fundamental problem with it was that patients received confused messages about the relation between HIV/AIDS and other STDs. This has potentially negative consequences for partner notification.

CONCLUSION

The intervention needs further development, and then could provide a highly acceptable, cost effective model for health education in clinics in developing countries.

CT-based assessment of acute stroke: CT, CT angiography, and xenon-enhanced CT cerebral blood flow

BACKGROUND AND PURPOSE

Only a small percentage of acute-stroke patients receive thrombolytic therapy because of time constraints and the risks associated with thrombolytic therapy. We sought to determine whether xenon-enhanced CT (XeCT) cerebral blood flow (CBF) and/or CT angiography (CTA) in conjunction with CT can distinguish subgroups of acute ischemic stroke victims and thereby better predict the subgroups most likely to benefit and not to benefit from thrombolytic therapy.

METHODS

An analysis of 51 patients who had a CT, CTA, and stable XeCT CBF examination within 24 hours of stroke symptom onset was conducted. These initial radiographic studies and National Institutes of Health Stroke Scale score on admission were assessed to determine whether they could predict new infarction on follow-up CT or discharge disposition by use of the Fisher exact test to determine statistical significance.

RESULTS

Patients with no infarction on initial CT and normal XeCT CBF had significantly fewer new infarctions and were discharged home more often than those with compromised CBF. The same held true for patients with an open internal carotid artery and middle cerebral artery by CTA and normal CT compared with those with an occluded internal carotid artery and/or middle cerebral artery by CTA. Either was superior to CT and the National Institutes of Health Stroke Scale in prediction of outcome. Both enable the selection of a group of patients not identifiable by CT alone that would do well without being exposed to the risks of thrombolytic therapy. This study included too few patients to statistically assess the role of combining CTA and XeCT CBF information.

CONCLUSIONS

The combination of CT, CTA, and Xe/CT CBF does define potentially significant subgroups of patients. The utility of this classification is supported by the observation that CTA and XeCT CBF are superior to CT alone in predicting infarction on follow-up CT and clinical outcome. This information may be useful in selecting patients for acute-stroke treatment.

Metoprolol controlled release/extended release in patients with severe heart failure: analysis of the experience in the MERIT-HF study

OBJECTIVES

This study analyzed the effect of the beta(1)-selective beta-blocker metoprolol succinate controlled release/extended release (CR/XL) once daily on mortality, hospitalizations and tolerability in patients with severe heart failure.

BACKGROUND

There continues to be resistance to the incorporation of beta-blockers into clinical care, largely due to concerns about their benefit in patients with more severe heart failure.

METHOD

SA subgroup of patients from Metoprolol CR/XL Randomized Intervention Trial in chronic Heart Failure (MERIT-HF) in New York Heart Association (NYHA) functional class III/IV with left ventricular ejection fraction < 0.25 were identified (n = 795). The analysis was by intention-to-treat.

RESULTS

The mean ejection fraction at baseline was 0.19, and the yearly placebo mortality during follow-up was 19.1%. Treatment with metoprolol CR/XL compared to placebo resulted in significant reductions in all predefined mortality end points including: total mortality, 45 versus 72 deaths (risk reduction 39%; 95% confidence interval 11% to 58%; p = 0.0086); sudden death, 22 vs. 39 deaths (45% [7% to 67%]; p = 0.024); and death due to worsening heart failure, 13 vs. 28 deaths (55% [13% to 77%]; p = 0.015). Metoprolol CR/XL also reduced the number of hospitalizations for worsening heart failure by 45% compared with placebo (p < 0.0001). The NYHA functional class improved in the metoprolol CR/XL group compared with placebo (p = 0.0031). Metoprolol CR/XL was well tolerated, with 31% fewer patients withdrawn from study medicine (all causes) compared with placebo (p = 0.027).

CONCLUSIONS

This subgroup analysis of the MERIT-HF study shows that patients with severe heart failure receive a similar mortality benefit and a similar reduction in hospitalizations for worsening heart failure with metoprolol CR/XL treatment as those patients included in the total study.

Seven cases of surgical native valve endocarditis caused by coagulase-negative staphylococci: An underappreciated disease

BACKGROUND

Native valve endocarditis caused by coagulase-negative staphylococci is uncommon and the diagnosis is infrequently considered. The disease, however, appears to be increasing in frequency and can pursue an aggressive clinical course. We report the clinical features of 7 cases of coagulase-negative staphylococcal native valve endocarditis (CNS-NVE) seen at 1 institution with a large cardiovascular referral base over a 10-month period. All cases required valve replacement surgery.

METHODS

Clinical history, echocardiograms, and microbiologic and histopathologic data were reviewed for 7 patients with surgical CNS-NVE.

RESULTS

Four patients had intravenous central catheters, and 1 had recent surgery, whereas the remaining 2 had no identifiable risk factors. Presentations ranged from subacute (4 cases) to acute with complications (3 cases). Complications included congestive heart failure, stroke, and heart block. Echocardiography demonstrated valvular lesions in all 7 cases. Valve pathologic study demonstrated gram-positive cocci in all 7 cases; blood cultures grew coagulase-negative staphylococci in 6 cases and valve cultures grew Staphylococcus epidermidis in 5 cases.

CONCLUSIONS

Coagulase-negative staphylococci, including S epidermidis, can cause severe native valve endocarditis requiring valve replacement. The increasing use of intravascular access devices in the community may herald an increase in the incidence of CNS-NVE. A high index of diagnostic suspicion in the appropriate clinical setting is critical for optimal management.

Recellularization of heart valve grafts by a process of adaptive remodeling

The objective of this study was to investigate if function and durability of connective tissue grafts stems from in vivo revascularization and recellularization. Viability is important for durable valve performance, demonstrated by pulmonary autografts. A pattern of in vivo recellularization occurs in xenogeneic or allogeneic heart valves decellularized prior to implantation, dictated by the tissue matrix and functional biomechanics. Porcine or sheep heart valves were decellularized with the SynerGraft antigen reduction process (a common treatment process to remove all histologically demonstrable leaflet cells), and implanted as pulmonary (n = 11) or aortic valve (n = 9) replacements in sheep. Sheep allograft pulmonary valves (n = 4) were implanted as pulmonary valve replacements. Recellularization was evaluated histologically after 3, 4, 5, 6, and 11 months, with cell phenotypes identified using specific antibodies. SynerGraft heart valves were progressively recellularized beginning with an initial cellular infiltrate, and subsequent repopulation with mature interstitial cells. This process occurs in the conduit and then in the leaflet, and is associated with revascularization of the graft. Functional, fully developed fibrocytes, actively synthesizing type I procollagen (antibody probe) were present within 3 months. As the process matured cell density and distribution became similar to native valve leaflets with localization of smooth muscle actin positive cells at the ventricularis/spongiosa interface. After 11 months, leaflet explants had no detectable inflammatory cells, were as much as 80% repopulated, and had a distribution of smooth muscle actin positive cells similar to that of the natural leaflet. SynerGraft- treated heart valve implants are repopulated by a process typical of adaptive remodeling following implantation. This antigen reduction treatment is the first successful tissue engineering effort obtaining an implant with mature recipient cells capable of matrix protein synthesis. Normal early valve function and durability is maintained.

High-pressure pulse-radiolysis study of the formation and decomposition of complexes with iron-carbon sigma bonds: mechanistic comparison for different metal centers

Volumes of activation for the formation and homolysis of the transient complexes (hedta)Fe(III)-CO(2)(2-) and (hedta)Fe(III)-CH(3)(-) (HOCH(2)CH(2)N(CH(2)CO(2-))CH(2)CH(2)N(CH(2)CO(2-))(2) = hedta) were determined using high-pressure pulse-radiolysis techniques. A comparison of the results with those for analogous complexes with other central transition-metal cations (M(n+)) and ligands (L) points out that (i) the reaction of M(n)L(m) with aliphatic radicals (R(*)) proceeds via an interchange ligand substitution mechanism, i.e. M(n)L(m) + R(*) --> L(m-1)M(n+1)-R + L, (ii) the homolysis of the metal-carbon bonds naturally follows the same mechanism, and (iii) the volume of activation for the homolysis reaction depends strongly on the nature of the central cation, i.e. larger for M(n+1) = Cr(III), Co(III), Ni(III) and smaller for Fe(III). The volume of activation for the reaction (hedta)Fe(III)-CO(2)(2-) + CO(2)(*-) + 2H(+) --> Fe(II)(hedta)(H(2)O)(-) + CO + CO(2) was measured, and the results enable a tentative proposal for the nature of the transition state of this interesting reaction.

Serial [18F] fluorodeoxyglucose positron emission tomography after human neuronal implantation for stroke

OBJECTIVE

There is no known effective treatment for chronic stroke. In this report, we used positron emission tomography (PET) with [18F]fluorodeoxyglucose (FDG) to map the metabolic brain response to neuronal cell implantation in the first human neuroimplantation trial for stroke.

METHODS

Twelve patients (nine men, three women; mean age +/- standard deviation, 60.8+/-8.3 yr) with chronic basal ganglia infarction and persistent motor deficit underwent FDG PET within 1 week before and 6 and 12 months after stereotactic implantation of human neuronal cells. Serial neurological evaluations during a 52-week postoperative period included the National Institutes of Health stroke scale and the European stroke scale.

RESULTS

Alterations in glucose metabolic activity in the stroke and surrounding tissue at 6 and 12 months after implantation correlated positively with motor performance measures.

CONCLUSION

FDG PET performed as part of an initial open-label human trial of implanted LBS-Neurons (Layton BioScience, Sunnyvale, CA) for chronic stroke demonstrates a relationship between relative regional metabolic changes and clinical performance measures. These preliminary findings suggest improved local cellular function or engraftment of implanted cells in some patients.

Carbonate radical ion is the only observable intermediate in the reaction of peroxynitrite with CO(2)

The reaction of ONOO(-) with CO(2) at alkaline pH was recently reported to form a transient absorption with a maximum at 640 nm and a half-life of ca. 4 ms at 10 degrees C [Meli et al. (1999) Helv. Chim. Acta 82, 722-725]. This transient absorption was hardly affected by the presence of *NO, and therefore was attributed to the adduct ONOOC(O)O(-). This conclusion contradicts all current experimental results as it suggests that the decomposition of this adduct via homolysis of the O-O bond into CO(3)(*)(-) and *NO(2) is a minor pathway. In the present work the observations of Meli et al. will be shown to be artifacts resulting from light coming from the UV region. When these experiments are carried out in the presence of appropriate cutoff filters, the only observable intermediate formed in the reaction of ONOO(-) with CO(2) at alkaline pH is the carbonate radical ion with a maximum at 600 nm. This transient absorption is not observed in the presence of *NO or ferrocyanide. In the latter case ferricyanide is formed, and its yield was determined to be 66 +/- 2% of the initial concentration of peroxynitrite. The reaction of ONOO(-) with 16 mM CO(2) with and without ferrocyanide was also studied at pH 5.6-7.7 in the presence of 0.1 M phosphate, where both the initial pH and [CO(2)] remain constant. Under these conditions the rate constant of the decay of peroxynitrite was found to be identical to that of the formation of ferricyanide, indicating that ONOOC(O)(-) does not accumulate. These results confirm our earlier observations, i.e., the reaction of peroxynitrite with excess CO(2) takes place via the formation of about 33% CO(3)(*)(-) and *NO(2) radicals in the bulk of the solution.

Challenges of subgroup analyses in multinational clinical trials: experiences from the MERIT-HF trial

BACKGROUND

International placebo-controlled survival trials (Metoprolol Controlled-Release Randomised Intervention Trial in Heart Failure [MERIT-HF], Cardiac Insufficiency Bisoprolol Study [CIBIS-II], and Carvedilol Prospective Randomized Cumulative Survival trial [COPERNICUS]) evaluating the effects of b-blockade in patients with heart failure have all demonstrated highly significant positive effects on total mortality as well as total mortality plus all-cause hospitalization. Also, the analysis of the US Carvedilol Program indicated an effect on these end points. Although none of these trials are large enough to provide definitive results in any particular subgroup, it is natural for physicians to examine the consistency of results across various subgroups or risk groups. Our purpose was to examine both predefined and post hoc subgroups in the MERIT-HF trial to provide guidance as to whether any subgroup is at increased risk, despite an overall strongly positive effect, and to discuss the difficulties and limitations in conducting such subgroup analyses.

METHODS

The study was conducted at 313 clinical sites in 16 randomization regions across 14 countries, with a total of 3991 patients. Total mortality (first primary end point) and total mortality plus all-cause hospitalization (second primary end point) were analyzed on a time to first event. The first secondary end point was total mortality plus hospitalization for heart failure.

RESULTS

Overall, MERIT-HF demonstrated a hazard ratio of 0.66 for total mortality and 0.81 for mortality plus all-cause hospitalization. The hazard ratio of the first secondary end point of mortality plus hospitalization for heart failure was 0.69. The results were remarkably consistent for both primary outcomes and the first secondary outcome across all predefined subgroups as well as for nearly all post hoc subgroups. The results of the post hoc US subgroup showed a mortality hazard ratio of 1.05. However, the US results regarding both the second primary combined outcome of total mortality plus all-cause hospitalization and of the first secondary combined outcome of total mortality plus heart failure hospitalization were in concordance with the overall results of MERIT-HF. Tests of country by treatment interaction (14 countries) revealed a nonsignificant P value of.22 for total mortality. The mortality hazard ratio for US patients in New York Heart Association (NYHA) class III/IV was 0.80, and it was 2.24 for patients in NYHA class II, which is not consistent with causality by biologic gradient. We have not been able to identify any confounding factor in baseline characteristics, baseline treatment, or treatment during follow-up that could account for any treatment by country interaction. Thus we attribute the US subgroup mortality hazard ratio to be due to chance.

CONCLUSIONS

Just as we must be extremely cautious in overinterpreting positive effects in subgroups, even those that are predefined, we must also be cautious in focusing on subgroups with an apparent neutral or negative trend. We should examine subgroups to obtain a general sense of consistency, which is clearly the case in MERIT-HF. We should expect some variation of the treatment effect around the overall estimate as we examine a large number of subgroups because of small sample size in subgroups and chance. Thus the best estimate of the treatment effect on total mortality for any subgroup is the estimate of the hazard ratio for the overall trial.

CD95 antigen mutations in hematopoietic malignancies

The CD95 receptor, also known as Fas/Apo-1, is a member of the Tumor Necrosis Factor receptor (TNF-R) family of death receptors. Apoptosis mediated by CD95 plays a central role in maintaining homeostasis of the immune system. Dysregulation of the CD95 apoptotic pathway has been proposed as a mechanism of oncogenesis by providing a survival advantage to potentially malignant cells. This extended lifespan could allow the accumulation of further mutations leading to malignant transformation. Several mechanisms of resistance to CD95 mediated apoptosis have been identified, including reduced surface expression of the receptor, overexpression of anti-apoptotic molecules, and loss of function mutations. This review will focus on the potential role of the CD95-CD95 ligand system in the pathogenesis of hematological malignancies, with particular emphasis on recent work from our laboratory examining the expression of CD95 in B cell lymphomas. We demonstrate that CD95 mutations occur at low frequency in NHL tumors, however, surface expression of the CD95 protein varies with the subtype of lymphoma. Loss of surface CD95 is more likely to occur in lymphomas of aggressive histology, and is unrelated to the detection of CD95 mutations.

Cerebrovascular reserve in patients with carotid occlusive disease assessed by stable xenon-enhanced ct cerebral blood flow and transcranial Doppler

BACKGROUND AND PURPOSE

Cerebrovascular reserve (CVR) by both transcranial Doppler ultrasonography (TCD) and quantitative cerebral blood flow (CBF) can identify subgroups of patients at increased risk for stroke. A direct comparison of CVR measurements obtained with both technologies in patients with cerebrovascular occlusive disease is lacking.

METHODS

CVRs before and after acetazolamide administration (1 g IV) were measured by TCD insonation of the middle cerebral artery (MCA) and CBF obtained with stable xenon CT (Xe/CT) in 38 patients with carotid occlusive disease. Sensitivity/specificity calculations were based on 2 Xe/CT MCA values: an average over 4 levels and the level with the lowest percent change in CBF. Compromised CVR was defined as no reactivity or a decrease in reactivity.

RESULTS

Using the analysis of the systolic TCD, we found that velocity changes compared with the average Xe/CT MCA CVR showed a sensitivity of 33%, specificity of 90.6%, positive predictive value of 54.5%, and negative predictive value of 80%. The sensitivity of TCD compared with the lowest Xe/CT CBF CVR was 35.5%, specificity and positive predictive values were 100%, and negative predictive value was 66.7%. The index of validity was between 72% and 76%.

CONCLUSIONS

TCD is much less sensitive than Xe/CT CBF in identifying patients with compromised CVR. This may be a result of the inability of TCD to identify patients with compromised reserves when their MCA blood flow comes from collateral sources. The lack of correlation between TCD and Xe/CT CBF for identifying patients with compromised CVR should be considered when stroke risk assessments are made by TCD.

Enhanced endothelium-dependent vasodilation in Fabry disease

BACKGROUND AND PURPOSE

Fabry disease is an X-linked lysosomal storage disease secondary to deficiency of alpha-galactosidase A with resulting glycolipid accumulation, particularly globotriaosylceramide in arterial smooth muscle and endothelial cells. A systemic vasculopathy, including early-onset stroke, is prevalent without a clear pathogenesis.

METHODS

Seventeen normotensive and normocholesterolemic hemizygous Fabry patients (aged 21 to 49 years) and 13 control subjects (aged 21 to 48 years) were investigated by venous plethysmography, allowing assessment of forearm blood flow. Plethysmographic measurements were obtained at baseline and during intra-arterial infusion of acetylcholine and sodium nitroprusside both with and without N(G)-monomethyl-L-arginine (L-NMMA).

RESULTS

Forearm blood flow was significantly higher in patients than in control subjects at all 3 acetylcholine doses (P=0.014). Patients had a greater response to acetylcholine even after the addition of L-NMMA (P=0.036).

CONCLUSIONS

These results demonstrate an increased endothelium-mediated vascular reactivity in Fabry disease. The increased vessel response to acetylcholine with and without L-NMMA suggests altered functionality of non-NO endothelium-dependent vasodilatory pathways.

Gibbs energy of formation of peroxynitrite--order restored

In a recent publication [Nauser et al. (2001) Chem. Res. Toxicol. 14, 248-350], the authors estimated a value of 14 +/- 3 kcal/mol for the standard Gibbs energy of formation of ONOO(-) and argued that the experimental value of 16.6 kcal/mol [Merényi, G., and Lind, J. (1998) Chem. Res. Toxicol. 11, 243-246] is in error. The lower value would suggest that the yield of free radicals during decomposition of ONOOH into nitrate is negligibly low, i.e., less than 0.5%, though within the large error limit given, the radical yield might vary between 0.003% and ca. 80%. The experimental value of 16.6 +/- 0.4 kcal/mol was based on the determination of the rate constant of the forward reaction in the equilibrium ONOO(-) <==> (*)NO and O2(*-) by use of C(NO2)4, an efficient scavenger of O2(*-) which yields C(NO2)3(-). Nauser et al. reported that addition of (*)NO has no significant effect on the rate of formation of C(NO2)3(-), and therefore the formation of C(NO2)3(-) is due to a process other then reduction of C(NO2)4 by O2(*-). In addition, they argued that Cu(II) nitrilotriacetate enhances the rate of peroxynitrite decomposition at pH 9.3 without reduction of Cu(II). In the present paper, we show that the formation of C(NO2)3(-) due to the presence peroxynitrite is completely blocked upon addition of (*)NO. Furthermore, the acceleration of the rate of peroxynitrite decomposition at pH 9 in the presence of catalytic concentrations of SOD ([ONOO(-)]/[SOD] > 30) results in the same rate constant as that obtained in the presence of C(NO(2))(4). These results can only be rationalized by assuming that ONOO(-) homolyses into (*)NO and O2(*-) with k = 0.02 s(-1) at 25 degrees C. Thus, the critical experiments suggested by Nauser et al. fully support the currently accepted thermodynamics as well as the mode of decomposition of the ONOOH/ONOO(-) system.

Sertraline treatment of posttraumatic stress disorder: results of 24 weeks of open-label continuation treatment

BACKGROUND

Posttraumatic stress disorder (PTSD) is typically associated with a high degree of chronicity, comorbidity, and psychosocial disability. The efficacy of sertraline in the acute treatment of PTSD has been confirmed based on the results of 2 large, placebo-controlled studies, but almost no prospective long-term treatment studies have been reported.

METHOD

One hundred twenty-eight patients who completed 12 weeks of double-blind, placebo-controlled, acute-phase treatment for DSM-III-R-defined PTSD with sertraline were continued into a 24-week open-label continuation phase. Efficacy was evaluated using the endpoint change in the 17-item Clinician Administered PTSD Scale Part 2 (CAPS-2) severity score, the 15-item patient-rated Impact of Event Scale, and the Clinical Global Impressions-Improvement and -Severity of Illness scales as primary outcome measures. Treatment response was defined as > or =30% decrease in the CAPS-2 total severity score (compared with acute-phase baseline score) and a Clinical Global Impressions-Improvement score of 1 or 2.

RESULTS

Ninety-two percent of acute-phase responders maintained their response during the full 6 months of continuation treatment. In addition, 54% of acute-phase nonresponders converted to responder status during continuation therapy. Over the 36-week course of acute and continuation therapy, 20% to 25% of the improvement in the CAPS-2 severity score occurred during the continuation phase. Sertraline was well tolerated, with 8.6% of patients discontinuing due to adverse events. A high pretreatment CAPS-2 score (> 75) predicted a longer time to response and a greater likelihood that response occurred after 12 weeks of acute treatment.

CONCLUSION

The acute efficacy of sertraline is sustained in the vast majority of patients, and at least half of nonresponders to acute treatment will eventually respond to continued treatment.

Decellularized human valve allografts

BACKGROUND

Variable performance of allograft tissues in children and some adults may be linked to an immune response and could be mitigated by reducing implant antigenicity.

METHODS

As endothelial and fibroblast cells are the likely source of valve antigenicity, human (CryoValve SG) and sheep pulmonary valves were decellularized using the SynerGraft treatment process. Treated valves were evaluated in vitro using histochemical, biomechanical, and hydrodynamic methods, and compared with standard cryopreserved valves. Four SynerGraft-treated and two cryopreserved sheep pulmonary valves were implanted as root replacements in the right ventricular outflow tract of growing sheep and monitored echocardiographically and histologically at 3 and 6 months. CryoValve SG human pulmonary valves were implanted in 36 patients.

RESULTS

SynerGraft treatment reduced tissue antigen expression but did not alter human valve biomechanics or strength. Decellularized sheep allograft valves were functional during the implantation period, and, they became progressively recellularized with recipient cells. In humans, CryoValve SG pulmonary valves did not provoke a panel reactive antibody response.

CONCLUSIONS

SynerGraft decellularization leaves the physical properties of valves unaltered and substantially diminishes antigen content. Reduction in implant cellularity enables host recellularization of the matrix, which should favorably impact long-term graft durability.

A survey of spinal and epidural techniques in adult cardiac surgery

OBJECTIVE

To determine if a significant number of anesthesiologists are performing spinal and epidural techniques in adults undergoing cardiac surgery and if any neurologic injuries have been associated with these techniques.

DESIGN

Anonymous survey of clinical practice.

SETTING

Data collected via mail from members of the Society of Cardiovascular Anesthesiologists.

PARTICIPANTS

Attending anesthesiologists.

INTERVENTIONS

Anesthesiologists completed an anonymous survey of their use of spinal and epidural techniques in adult patients undergoing cardiac surgery.

MEASUREMENTS AND MAIN RESULTS

Of 3974 anesthesiologists, 974 (24%) responded to the questionnaire; 892 are at institutions that perform cardiac surgery. Of the 892 responders, 68 (7.6%) reported they use spinal techniques, whereas 62 (7%) reported they use epidural techniques. Nine (1%) anesthesiologists reported they use both techniques. There were no reports of neurologic complications related to the use of spinal or epidural techniques performed by the anesthesiologists responding to the survey.

CONCLUSIONS

A significant number of anesthesiologists are performing spinal and epidural techniques in adult patients undergoing cardiac surgery. Prospective, controlled trials should be performed to evaluate the benefits and risks of spinal and epidural techniques in this population.

Acute lower gastrointestinal bleeding as a late complication of spinal instrumentation

Posterior or anterior fusion with spinal instrumentation is a well-known operation for scoliosis. There are multiple potential complications; the most common are blood loss during the initial surgery and wound infection. Vascular injury has been reported. However, to the authors' knowledge, acute gastrointestinal bleeding has not been reported. The authors report on a child who presented 6 years after posterior spinal instrumentation with massive acute lower gastrointestinal bleeding resulting from internal iliac artery injury and bowel perforation. The etiology, diagnosis, and management of such bleeding is reviewed.

Somatosensory evoked potentials as a marker of disease burden in type 3 Gaucher disease

The authors compared stretch-evoked somatosensory evoked potentials (SEP) of 18 type 3 Gaucher disease (GD3) patients (two with progressive myoclonus epilepsy [PME]) with 22 age-matched normal controls and six patients with type 1 (nonneuronopathic) Gaucher disease (GD1). The mean P1-N2 SEP amplitude in GD3 patients was significantly larger than the SEP in controls and in GD1 patients, and there was a significant negative correlation between SEP amplitude and the IQ of GD3 patients. The authors conclude that abnormal cortical inhibition is a unifying feature of GD3 patients and correlates with the degree of cognitive deficit.

Cardiac contractility modulation with the impulse dynamics signal: studies in dogs with chronic heart failure

The intravenous use of positive inotropic agents, such as sympathomimetics and phosphodiesterase inhibitors, in heart failure is limited by pro-arrhythmic and positive chronotropic effects. Chronic use of these agents, while eliciting an improvement in the quality of life of patients with advanced heart failure, has been abandoned because of marked increase in mortality when compared to placebo. Nevertheless, patients with advanced heart failure can benefit from long-term positive inotropic support if the therapy can be delivered 'on demand' and in a manner that is both safe and effective. In this review, we will examine the use of a novel, non-stimulatory electrical signal that can acutely modulate left ventricular (LV) contractility in dogs with chronic heart failure in such a way as to elicit a positive inotropic support. Cardiac contractility modulation (CCM) with the Impulse Dynamic(trade mark) signal was examined in dogs with chronic heart failure produced by intracoronary microembolizations. Delivery of the CCM signal from a lead placed in the great coronary vein for periods up to 10 minutes resulted in significant improvements in cardiac output, LV peak+dP/dt, LV fractional area of shortening and LV ejection fraction measured angiographically. Discontinuation of the signal resulted in a return of all functional parameters to baseline values. In cardiomyocytes isolated from dogs with chronic heart failure, application of the CCM signal resulted in improved shortening, rate of change of shortening and rate of change of relengthening suggesting that CCM application is associated with intrinsic improvement of cardiomyocyte function. The improvement in isolated cardiomyocyte function after application of the CCM signal was accompanied by an increase in the peak and integral of the Ca(2+) transient suggesting modulation of calcium cycling by CCM application. In a limited number of normal dogs, intermittent chronic delivery of the CCM signal for up to 7 days showed chronic maintenance of LV functional improvement. In conclusion, pre-clinical results to date with the Impulse Dynamics CCM signal indicate that this non-pharmacologic therapeutic modality can provide short-term positive inotropic support to the failing heart and as such, may be a useful adjunct in the treatment of advanced heart failure. Additional, long-term studies in dogs with heart failure are needed to establish the safety and efficacy of this therapeutic modality for the chronic treatment of this disease syndrome.