Dose selection for a direct and selective factor IXa inhibitor and its complementary reversal agent: translating pharmacokinetic and pharmacodynamic properties of the REG1 system to clinical trial design.

We performed detailed pharmacokinetic and pharmacodynamic modeling of REG1, an anticoagulation system composed of the direct factor IXa (FIXa) inhibitor pegnivacogin (RB006) and its matched active control agent anivamersen (RB007), with a focus on level of target inhibition to translate phase 1 results to phase 2 dose selection. We modeled early-phase clinical data relating weight-adjusted pegnivacogin dose and plasma concentration to prolongation of the activated partial thromboplastin time (aPTT). Using an in vitro calibration curve, percent FIXa inhibition was determined and related to aPTT prolongation and pegnivacogin dose and concentration. Similar methods were applied to relate anivamersen dose and level of reversal of pegnivacogin anticoagulation. Combined early-phase data suggested that ≥0.75 mg/kg pegnivacogin was associated with >99% inhibition of FIX activity and prolongation of plasma aPTT values ≈2.5 times above baseline, leading to selection of a 1 mg/kg dose for a phase 2a elective percutaneous coronary intervention study to achieve a high intensity of anticoagulation and minimize intersubject variability. Phase 2 validated our predictions, demonstrating 1 mg/kg pegnivacogin yielded plasma concentrations ≈25 µg/ml and >99% inhibition of FIX activity. The relationship between the anivamersen to pegnivacogin dose ratio and degree of pegnivacogin reversal was also validated. Our approach decreased the need for extensive dose-response studies, reducing the duration, complexity and cost of clinical development. The 1 mg/kg pegnivacogin dose and a range of anivamersen dose ratios are being tested in the phase 2b RADAR study (NCT00932100).

Incidence and management of "no-reflow" following percutaneous coronary interventions.

No-reflow is a complex condition associated with inadequate myocardial perfusion of the coronary artery in the absence of epicardial obstruction. It can occur in several settings, including percutaneous coronary intervention, especially in complex thrombotic lesions of native arteries and vein grafts and in primary angioplasty. The causes of no-reflow are not completely understood, and current treatments consist of intracoronary vasodilators, antithrombotic therapies, and mechanical devices (including aspiration thrombectomy catheters and embolic protection devices).

The no-reflow phenomenon in coronary arteries.

No reflow occurs when there is inadequate myocardial perfusion of a given segment of the coronary circulation without evidence of epicardial vessel obstruction. It is a rare but clinically significant condition associated with myocardial infarction and coronary interventions. Diagnosis is usually based on clinical signs of myocardial ischemia (symptoms and/or ECG changes) combined with coronary angiography. Management can be difficult and primarily consists of intracoronary administration of vasodilators. One interesting etiology is thromboembolism and this has become the focus for new potential treatments, including distal embolic protection devices.

Clinical, electrocardiographic, and biochemical data for immediate risk stratification in acute coronary syndromes.

The recent evolution in therapeutic options for acute coronary syndromes (ACS) mandates early risk stratification in order to select the appropriate treatment strategy for individual patients. Simple clinical data derived from the patient's medical history and physical examination, a standard twelve-lead electrocardiogram (ECG), and determinations of biochemical markers of myocardial damage can be obtained in the emergency room and serve as a guide for deciding appropriate medical management and optimal use of available resources. Even the most important classification of the ACS is based upon a simple and dichotomous description of the ECG, where the presence of ST-segment elevation mandates an immediate attempt to restore coronary perfusion (either pharmacologically or mechanically), whereas its absence suggests pharmacological stabilization before further evaluation. Across the whole spectrum of ACS, clinical history data (such as older age, previous coronary events, and diabetes) and clinical variables (such as higher heart rate, lower blood pressure, and higher Killip class) are the most powerful prognostic determinants at multivariate analyses derived from large databases. The ECG adds significant and independent prognostic information using the analysis of qualitative (direction of ST-segment shift, associated T-wave inversion, and presence of conduction disturbances) and quantitative (number of leads involved, amount of ST- segment shifts, duration of QRS) characteristics. Biochemical markers of myocardial damage have also been identified as independent predictors of events. In addition, retrospective analyses of clinical trials have suggested that biochemical markers might serve as a guide to select pharmacological therapy. However, how to best combine electrocardiographic and biochemical data for immediate risk stratification remains to be further elucidated.

Variation in patient management and outcomes for acute coronary syndromes in Latin America and North America: results from the Platelet IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) trial.

BACKGROUND: Although more than 9500 patients have been enrolled in major clinical trials in Latin America, practice patterns in this region have rarely been examined. We sought to compare characteristics, resource utilization, and outcomes of patients treated for acute coronary syndromes in Latin America with those in North America. METHODS: The Platelet IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Theraphy Trial (PURSUIT) enrolled 10,948 patients with non-ST-segment elevation acute coronary syndromes, including 585 in Latin America and 4358 in North America. We analyzed regional differences in patient groups, treatment patterns, and outcomes and used logistic regression analysis to identify association of enrollment region and survival. RESULTS: For patients in Latin America, the length of hospital stay was significantly longer (10 [7, 15] days vs 6 [4, 9], P <.001). Angiograms, angioplasty, and bypass surgery were significantly less common in Latin America (46.2%, 17.6%, and 11.3% vs 79.4%, 33.6%, and 19.4%, P <.001). Thirty-day death/myocardial infarction was not significantly higher, although mortality alone was significantly higher (6.8% vs 3.1%, P <.001). After adjustment for baseline characteristics, enrollment in Latin America remained an independent predictor for death at 30 days (odds ratio [OR] [95% confidence interval (CI)] 2.42 [1.60-3.67]) and persisted at 6 months (OR [95% CI] 2.5 [1.8-3.4]). CONCLUSIONS: Latin American patients treated for acute coronary syndromes were managed less invasively and were twice as likely as their North American counterparts to die within 6 months. This mortality difference was not explained by imbalances in baseline risk.

The effects of practice and instruction on speed and accuracy during resident acquisition of simulated laparoscopic skills.

To assess the effects of practice and dynamic instruction on changes in speed and accuracy during acquisition of simulated laparoscopic surgical skills.Fourteen PGY-1 general surgery residents were randomly assigned to 1 of 2 experimental conditions (n = 7 per group), either practice only or practice with instruction, and required to perform 10 trials of each of 2 laparoscopic surgical skills-cannulation and object passing. Practice only subjects were given verbal instructions for each task, and corrective feedback only after trial 1. Practice with instruction subjects were treated the same, but also saw a videotaped demonstration and received dynamic feedback during and between each trial. Performance speed was recorded for each trial and number of errors was recorded for trials 8 to 10 by videotape review.Mean speed for subjects in both groups increased significantly for both tasks (p < 0.01). Practice with instruction subjects committed significantly fewer errors on object passing (p < 0.04) and were less variable in the number of errors committed during the cannulation task (p < 0.01).Practice, with or without dynamic instruction, results in significant improvement in the speed of performance of simulated laparoscopic surgical skills. The addition of dynamic instruction to simulator-based practice improves the quality and consistency of resident acquisition of laparoscopic surgical skills.

Syphilitic aortitis.

A case of syphilitic aortitis, complicated by bilateral coronary ostial stenosis, in a 40-year-old man is described. Treatment included coronary artery bypass grafting and a drug regimen of penicillin. At 3-month follow-up, an exercise stress test revealed no signs of ischemia.

Granular cell tumor--a unique neoplasm of the internal anal sphincter: report of a case.

Granular cell tumors are rare, invariably benign, and often solitary tumors, which infrequently involve the gastrointestinal tract. We report the unique presentation of a granular cell tumor of the internal anal sphincter in a 75 year-old female. The tumor was detected during investigation of new rectal bleeding and was excised using a transanal approach and sphincter repair. At five-year follow-up the patient reported normal continence to stool and flatus and demonstrated no evidence of tumor recurrence. Immunohistochemical studies cite the Schwann neural cell as the origin of the granular cell tumor. Cytoplasmic features include acidophilic, p-aminosalicylic acid-positive, diastaseresistant granules. Granular cell tumors may be located anywhere in the body, but anorectal involvement is rare. In our own search of the world literature, no other cases were reported specifically to involve the anal sphincter. Granular cell tumors are usually detected incidentally but may be symptomatic, especially when the anorectal region is involved. Symptoms include perianal discomfort and bleeding. Adequate local excision is effective for both diagnosis and treatment of anorectal granular cell tumors. Careful follow-up should be performed after excision because of the risk of recurrence.

Outcomes following interventions in small coronary arteries with the use of hand-crimped Palmaz-Schatz stents.

Although coronary stenting has been shown to be effective, retrospective studies have suggested that stents do not provide better results than angioplasty in small coronary arteries. We sought to examine procedural, in-hospital, and long-term outcomes of patients undergoing small-vessel stenting with Palmaz-Schatz stents hand-crimped on a balloon catheter <3 mm in diameter. We retrospectively analyzed the outcomes of 117 patients who underwent this type of coronary stent implantation at Duke University Medical Center between January 1, 1997 and May 30, 1998. The clinical indications for percutaneous revascularization included unstable angina in 67.5% of patients, acute myocardial infarction in 4.3%, postinfarct angina in 3.4%, silent ischemia in 3.4%, and stable angina in 1% of patients. Quantitative angiographic analysis was performed immediately before angioplasty and after stent implantation. Stents were used for elective indications in 24%, for suboptimal angiographic result in 61.5%, and for abrupt and/or threatened closure in 14.5% of patients. Reference vessel diameter was similar before and after the procedure. Minimum luminal diameter increased from 0.63 to 2.35 mm, an acute gain of 1.72+/-0.43 mm. Percent stenosis decreased from 74.2% to 4.7%. The clinical composite of death (n = 1, 1%), nonfatal myocardial infarction (n = 6, 5.1%), and revascularization (n = 1, 1%) occurred in-hospital in only 8 patients (6.8%), resulting in clinical procedure success in 109 patients (93%). Our data suggest that stents designed for vessels >3.0 mm can be deployed in small vessels, with a low in-hospital event rate. However, target lesion revascularization in small vessels remains high. Development of antiproliferative strategies could improve long-term outcomes for small-vessel interventions.

Jejunal diverticulosis: a rare entity with multiple presentations, a series of cases.

BACKGROUND/AIMS: Jejunal diverticulosis (JD) is a rare disease that has a variable presentation. The signs, symptoms, diagnosis, complications and treatment of JD will be discussed through a review of the literature and a series of cases from our own institution. METHODS: A retrospective analysis of the diagnosis, treatment and complications of JD was performed by a literature review. This was accompanied by a series of four cases of JD diagnosed and treated in our own institution. CONCLUSIONS: JD is a rare disease in which most patients are asymptomatic. However, JD's different complications are serious and can be fatal. The treatment is mainly surgical; however, there have been cases where nonsurgical management was successful.

Outcome of Hispanic patients treated with thrombolytic therapy for acute myocardial infarction: results from the GUSTO-I and III trials. Global Utilization of Streptokinase and TPA for Occluded Coronary Arteries.

OBJECTIVES: We sought to describe the differences in the process of care and clinical outcomes between Hispanics and non-Hispanics receiving thrombolytic therapy for myocardial infarction (MI). BACKGROUND: Hispanics are the fastest growing and second largest minority in the U.S. but most cardiovascular disease data on Hispanics has been derived from retrospective studies and vital statistics. Despite their higher cardiovascular risk-factor profile, better outcomes after MI have been reported in Hispanics. METHODS: We studied the baseline characteristics, resource use and outcomes of 734 Hispanics and 27,054 non-Hispanics treated for MI in the GUSTO-I and -III trials. The primary end point of both trials was 30-day mortality. RESULTS: Hispanics were younger, shorter, lighter and more often diabetic and began thrombolysis 9 min later, compared with non-Hispanics. Measures of socioeconomic status (educational level, employment and health insurance) were lower among Hispanics. Fewer Hispanics than non-Hispanics underwent in-hospital angiography (70% vs. 74%, p = 0.013) or bypass surgery (11% vs. 13.5%, p = 0.04). Hispanics received more angiotensin-converting enzyme (ACE) inhibitors and less calcium-channel blockers, prophylactic lidocaine and inotropic agents. Mortality at 30 days and at one year did not differ significantly between Hispanics and non-Hispanics (6.4% vs. 6.7% and 9.0% vs. 9.7%, respectively). We noted no interactions between thrombolytic strategy and Hispanic status on major outcomes (30-day death, stroke and major bleeding). CONCLUSIONS: The care of Hispanics with MI differed slightly from that of non-Hispanics. Nevertheless, these differences in care did not affect long-term outcomes.

Hemiballismus in systemic lupus erythematosus: possible association with antiphospholipid antibodies.

The neuropsychiatric manifestations of systemic lupus erythematosus (SLE) are diverse but, among them, movement disorders are distinctly uncommon. We describe a 30-year-old female with SLE who developed sudden onset of right-sided hemiballismus. Previous cerebral venous thrombosis and a poor obstetric history suggested the antiphospholipid syndrome but only minimally elevated levels of anticardiolipin antibodies were detected. The underlying pathology could not be established but was most likely to have been a microinfarct of the contralateral subthalamic nucleus. Our patient responded rapidly to haloperidol alone without the requirement for corticosteroids.

Psoriatic arthritis: outcome of disease subsets and relationship of joint disease to nail and skin disease.

Subgroups of PsA have been described but their relationship to the mode of onset of arthritis, to DIP joint disease and to nail and skin disease remains controversial. Therefore, the pattern of disease was documented in 100 patients with PsA in whom the mode of onset was known. The patients were divided into six subgroups: monoarthritis; DIP joint disease only; oligoarthritis; polyarthritis; spondyloarthropathy and arthritis mutilans. Sixty-four patients changed pattern. Nail disease (67% of total) was more common in patients with DIP joint disease (27% of total) and was significantly associated with adjacent DIP joint disease. Skin and nail disease severity did not correlate with joint severity, joint activity or functional status, nor differ between subgroups. Therefore, the mode of onset does not predict outcome in the majority. The topographic association of nail disease and involvement of the adjacent DIP joints suggests a common local inflammatory mechanism.

SLE-associated thrombocytopenia in pregnancy: successful outcome with combined IgG infusion and platelet transfusion.

Autoimmune thrombocytopenia presents special problems during pregnancy because of the limited therapeutic options and the risks posed by even moderate degrees of thrombocytopenia. Although corticosteroids and intravenous immunoglobulin G (IV IgG) have been shown to be useful and relatively safe therapies, they are not always effective. We describe a patient with systemic lupus erythematosus (SLE) who developed severe thrombocytopenia unresponsive to prednisone and IV IgG. The combination of IV IgG and platelet transfusion immediately before delivery resulted in a rapid rise in platelet count and allowed a lower segment caesarean section to be undertaken without perioperative complication.

Rheumatic manifestations of hyperlipidemia and antihyperlipidemia drug therapy.

Conflicting data exist with respect to the existence and clinical manifestations of a hyperlipidemic arthropathy. Reasonable evidence supports the existence of a migratory polyarthritis similar to rheumatic fever in patients homozygous for type II hyperlipidemia. Although similar complaints have been described in patients heterozygous for this condition, findings have been inconsistent among various reports. It is possible that high lipid levels are required to induce rheumatic complaints, and these are found predominantly in homozygous patients. Even so, rheumatic syndromes appear to be more attributable to periarthritis because evidence of inflammatory arthritis is largely lacking. In contrast, Achilles tendinitis appears to be associated with heterozygous type II hyperlipidemia and presumably is based on lipid deposits within the tendon. Gout is an accepted association of type IV hyperlipidemia. In addition, oligoarticular symptoms have been described with type IV hyperlipidemia. However, no consistent clinical entity has emerged. Drugs used in the treatment of hyperlipidemia are associated with a variety of rheumatic problems, including proximal myopathy and lupus-like syndromes. The most commonly implicated drugs are the hydroxymethylglutaryl-coenzyme A reductase inhibitors and the fibric acid derivatives.