Effectiveness and safety of glycoprotein IIb/IIIa inhibitors in patients with myocardial infarction undergoing primary percutaneous coronary intervention: a meta-analysis of observational studies

INTRODUCTION

Meta-analyses of randomized controlled trials (RCT) showed that glycoprotein IIb/IIIa inhibitors (GPI) are associated with reduced adverse events following primary percutaneous coronary revascularization (PCI). However, the external validity of RCTs is generally limited due to their restricted inclusion of patients. The objective of this study is to evaluate the effectiveness and safety of GPI, as adjuvant therapy for primary PCI in real-life patients with myocardial infarction with ST segment elevation (STEMI) from the general population.

METHODS

We identified all published peer-reviewed observational studies enrolling STEMI patients who underwent primary PCI. We performed random-effect meta-analyses to determine the association of GPI with major adverse events.

RESULTS

A total of 11 studies, enrolling 12,253 patients, were retained for this meta-analysis. GPI was associated with approximately 53% reduction in short-term mortality (odds ratio (OR): 0.47, 95% confidence intervals (CI): 0.32-0.68). There was a 62% reduction in long-term mortality associated with GPI (OR: 0.38, 95% CI: 0.30-0.50). GPI was associated with a 62% reduction in 30-day re-infarction (OR: 0.38, 95% CI: 0.24-0.60) and 42% reduction in 30-day repeat PCI (OR: 0.58, 95% CI: 0.36-0.94). A non-significant increase in major bleeding with GPI was observed with an OR of 1.55 (95% CI: 0.92-2.62).

CONCLUSIONS

GPI is associated with significant reductions in short-term mortality, re-infarction and repeat PCI, long-term mortality and an inconclusive increase in major bleeding. These results provide evidence for the safety and effectiveness of GPI as adjuvant therapy for primary PCI in real-life STEMI patients.

Acute anti-emetic withdrawal associated with a hemorrhagic cerebellar arteriovenous malformation

We present a 67-year-old right-handed male with a brachium pontis arteriovenous malformation on continuous anti-emetic therapy who demonstrated acute withdrawal symptoms after the abrupt discontinuation of ondansetron, a 5-HT(3) receptor antagonist. Removal of anti-emetic therapy led to the development of extreme flushing and tremor, but subsequent return of ondansetron resulted in the resolution of these symptoms. This is the first clinical report demonstrating acute withdrawal from an anti-emetic agent and we further highlight the need for future studies evaluating not only arterial supply with pressure gradients and anatomical location, but also the association with periventricular venous drainage, venous drainage stenosis, and mass effect from venous stasis as this may contribute partly to the sensitivity of the serotonergic receptors seen here.

Effect of different angiotensin-converting-enzyme inhibitors on mortality among elderly patients with congestive heart failure

BACKGROUND

Existing clinical trial data do not address whether all angiotensin-converting-enzyme (ACE) inhibitors are similarly beneficial in improving survival and reducing the rate of readmission among patients with congestive heart failure. We sought to answer this question using administrative databases from Canada's 3 most populous provinces.

METHODS

Using linked hospital discharge and prescription claims databases in Quebec, Ontario and British Columbia, we identified all patients 65 years or older who were admitted to hospital because of congestive heart failure between Jan. 1, 1998, and Mar. 31, 2002, and who had not been admitted for the same reason in the 3 years preceding the study period. We analyzed the association between the type of ACE inhibitor prescribed within 30 days after discharge and subsequent mortality using Cox proportional hazards models. We then adjusted for demographic, clinical, physician and hospital-related variables, with additional time-dependent variables representing current drug use and dosage. We chose ramipril as the reference category for comparison with the other ACE inhibitors because it has increasingly been prescribed to patients with congestive heart failure.

RESULTS

A total of 43 316 patients with congestive heart failure filled prescriptions for ACE inhibitors within 30 days after discharge from hospital. Demographic, clinical and prescription-related characteristics were similar among users of each type of ACE inhibitor. In the time-dependent model, the mortality associated with 5 ACE inhibitors was similar to that with ramipril: adjusted hazard ratios (and 95% confidence intervals [CIs]) were 0.95 (0.89-1.02) for lisinopril, 0.92 (0.85-1.00) for fosinopril, 0.99 (0.88-1.11) for quinapril, 0.90 (0.77-1.06) for perindopril and 1.00 (0.80-1.24) for cilazapril. However, use of enalapril or captopril was associated with higher mortality compared with ramipril: adjusted hazard ratios (and 95% CIs) were 1.10 (1.04-1.16) for enalapril and 1.13 (1.01-1.26) for captopril.

INTERPRETATION

When prescribing ACE inhibitors to patients, physicians should consider a possible 10%-15% increase in mortality with captopril and enalapril compared with ramipril among patients with congestive heart failure.

Specification of hypothalamic neurons by dual regulation of the homeodomain protein Orthopedia

In the developing hypothalamus, a variety of neurons are generated adjacent to each other in a highly coordinated, but poorly understood process. A critical question that remains unanswered is how coordinated development of multiple neuronal types is achieved in this relatively narrow anatomical region. We focus on dopaminergic (DA) and oxytocinergic (OT) neurons as a paradigm for development of two prominent hypothalamic cell types. We report that the development of DA and OT-like neurons in the zebrafish is orchestrated by two novel pathways that regulate the expression of the homeodomain-containing protein Orthopedia (Otp), a key determinant of hypothalamic neural differentiation. Genetic analysis showed that the G-protein-coupled receptor PAC1 and the zinc finger-containing transcription factor Fezl act upstream to Otp. In vivo and in vitro experiments demonstrated that Fezl and PAC1 regulate Otp at the transcriptional and the post-transcriptional levels, respectively. Our data reveal a new genetic network controlling the specification of hypothalamic neurons in vertebrates, and places Otp as a critical determinant underlying Fezl- and PAC1-mediated differentiation.

Treating opioid addiction with buprenorphine-naloxone in community-based primary care settings

PURPOSE

Office-based treatment of opioid addiction with a combination of buprenorphine and naloxone was approved in 2002. Efficacy of this treatment in non-research clinical settings has not been studied. We examined the efficacy and practicality of buprenorphine-naloxone treatment in primary care settings.

METHODS

We studied a cohort of 99 consecutive patients enrolled in buprenorphine-naloxone treatment for opioid dependence at 2 urban primary care practices: a hospital-based primary care clinic, and a primary care practice in a free-standing neighborhood health center. The primary outcome measure was sobriety at 6 months as judged by the treating physician based on periodic urine drug tests, as well as frequent physical examinations and questioning of the patients about substance use.

RESULTS

Fifty-four percent of patients were sober at 6 months. There was no significant correlation between sobriety and site of care, drug of choice, neighborhood poverty level, or dose of buprenorphine-naloxone. Sobriety was correlated with private insurance status, older age, length of treatment, and attending self-help meetings.

CONCLUSIONS

Opioid-addicted patients can be safely and effectively treated in non-research primary care settings with limited on-site resources. Our findings suggest that greater numbers of patients should have access to buprenorphine-naloxone treatment in nonspecialized settings.

Reconsolidation of fresh, remote, and extinguished fear memory in Medaka: old fears don't die

Long-term fear memory in the medaka fish (Oryzias latipes) regains transient sensitivity to a consolidation blocker immediately after memory reactivation in retrieval ('reconsolidation'). Here we show that reconsolidation occurs in fresh long-term memories but not in remote memories, and that the apparent amnesia induced by blockade of reconsolidation can be reinstated by an unpaired reinforcer, a procedure that has no effect on amnesia induced by blockade of consolidation. Extinction memory also undergoes post-reactivation reconsolidation, the blockade of which exposes the previously acquired fear. Hence in medaka, the process manifested in reconsolidation seems itself to consolidate; moreover, even when the post-reactivation application of the consolidation blocker is still able to disrupt the memory, the conditioned fear does not seem to go away permanently.

Rites of Passage of the Engram

Memory consolidation refers to the progressive stabilization of items in long-term memory as well as to the memory phase(s) during which this stabilization takes place. The textbook account is that, for each item in memory, consolidation starts and ends just once. In recent years, however, the notion that memories reconsolidate upon their reactivation and hence regain sensitivity to amnestic agents has been revitalized. This issue is of marked theoretical and clinical interest. Here we review the recent literature on reconsolidation and infer, on the basis of the majority of the data, that blockade of reconsolidation does not induce permanent amnesia. Further, in several systems, reconsolidation occurs only in relatively fresh memories. We propose a framework model, which interprets reconsolidation as a manifestation of lingering consolidation, rather than recapitulation of a process that had already come to a closure. This model reflects on the nature of consolidation in general and makes predictions that could guide further research.

Stability of retrieved memory: inverse correlation with trace dominance

In memory consolidation, the memory trace stabilizes and becomes resistant to certain amnesic agents. The textbook account is that for any memorized item, consolidation starts and ends just once. However, evidence has accumulated that upon activation in retrieval, the trace may reconsolidate. Whereas some authors reported transient renewed susceptibility of retrieved memories to consolidation blockers, others could not detect it. Here, we report that in both conditioned taste aversion in the rat and fear conditioning in the medaka fish, the stability of retrieved memory is inversely correlated with the control of behavior by that memory. This result may explain some conflicting findings on reconsolidation of activated memories.

The steroid-responsive hiccup reflex arc: competitive binding to the corticosteroid-receptor?

Hiccups occurring secondary to high-doses of corticosteroids are a well-recognized problem in the field of neurosurgery. Numerous reports of oral, intravenous and intraarticular corticosteroids inducing hiccups exist in the literature. To date, there is only one case of anabolic steroids inducing hiccups. We now present a case of a patient who underwent a suboccipital craniotomy for resection of a cerebellar pontine angle meningioma. Postoperatively the patient was on high doses of Decadron and Oxandrin, an anabolic-anticatabolic agent used to combat the deleterious effects of corticosteroids. The patient suffered intractable hiccups postoperative day one, resistant to Thorazine. Oxandrin was discontinued to assess the possibility of a anabolic steroid-induced singultus. The hiccups resolved within 24 hours. This report validates the previous report on anabolic steroids inducing hiccups and exemplifies the ability for steroids as a class, due to there backbone structural homology, to induce function even as competitive inhibitors.

Effects of hospital volume on long-term outcomes after percutaneous transluminal coronary angioplasty after acute myocardial infarction

BACKGROUND

Volume of procedures has been associated with short-term outcome after percutaneous transluminal coronary angioplasty. However, the effect of hospital procedural volume on long-term outcome after PTCA is unknown.

METHODS AND RESULTS

We analyzed the physician claims and discharge data of 6635 patients who underwent PTCA after acute myocardial infarction (AMI) between 1991 and 1995 in the province of Quebec, Canada. For each administrative year, hospitals in which PTCA was performed were classified into 3 groups: low-volume, <200 procedures per year; medium-volume, 200 to 399 procedures per year; and high-volume, > or =400 procedures per year. Compared with patients in medium-volume and high-volume hospitals, patients in low-volume hospitals were older, had more recent AMI, and were less likely to have been transferred for PTCA. After adjustment for baseline differences, patients in the low-volume and medium-volume groups were more likely to undergo CABG within 6 months compared with patients in the high-volume group (odds ratio [OR] 2.1, 95% CI 1.3-3.3, and OR 1.5, 95% CI 1.2-1.9, respectively). In contrast, patients in the low-volume and medium-volume groups were less likely than patients in the high-volume group to undergo repeat PTCA within 6 months (OR 0.37, 95% CI 0.24-0.58, and OR 0.8, 95% CI 0.70-0.92, respectively). At 6 months, adjusted rates of repeat revascularization, recurrent AMI, or death did not differ between the 3 groups.

CONCLUSION

Overall adverse event rates at 6 months after PTCA do not differ between hospital volume groups. The higher rate of CABG in low-volume hospitals and the higher rate of repeat PTCA in high-volume hospitals may represent different physician preferences for the treatment of failed PTCA rather than higher complication rates.