Heart-type fatty acid-binding protein (H-FABP) as an early diagnostic biomarker in patients with acute chest pain

Background

Heart-type fatty acid-binding protein (H-FABP) is an emerging biomarker, which was found to be sensitive for the early diagnosis of acute myocardial infarction (AMI). We prospectively investigated the usefulness of H-FABP determination for the evaluation of acute chest pain in patients arriving at the emergency department.

Methods

Fifty-four patients presenting with acute ischemic chest pain were evaluated. H-FABP was estimated at admission using latex-enhanced immunoturbidimetric assay. Serial cardiac troponin I (cTnI), creatinine kinase-MB (CK-MB) determination, ischemia workup with stress testing, and/or coronary angiogram (CAG) were performed according to standard protocols.

Results

The sensitivity and specificity of H-FABP was 89.7% and 68%, for cTnI it was 62.1% and 100%, and for CK-MB it was 44.8% and 92%, respectively for diagnosis of AMI. The sensitivity of H-FABP was found to be far superior to initial cTnI and CK-MB, for those seen within 6 h (100% vs. 46.1%, 33% respectively). On further evaluation of patients with positive H-FABP and negative cTnI, 71.4% of the patients had significant lesion on CAG, indicating ischemic cause of H-FABP elevation. Six patients with normal cTnI and CK-MB with high H-FABP had ST elevation on subsequent ECGs and were taken for primary angioplasty.

Conclusion

H-FABP is a highly sensitive biomarker for the early diagnosis of AMI. H-FABP as early marker and cTnI as late marker would be the ideal combination to cover the complete diagnostic window for AMI. Detection of myocardial injury by H-FABP may also be applied in patients with unstable angina. H-FABP can also be used as a marker for early detection of STEMI before the ECG changes become apparent.     

Post-traumatic stress disorder following myocardial infarction: Prevalence and risk factors

BACKGROUND:

Post-traumatic stress disorder (PTSD) is associated with negative impacts on physical health. Victims of a myocardial infarction (MI) who develop PTSD may be particularly affected by these impacts due to their cardiovascular vulnerability. Post-traumatic reactions in this population are not well known.

OBJECTIVES:

To examine the prevalence of PTSD after MI and its risk factors, and to validate a prediction model for PTSD symptoms.

METHODS:

Patients hospitalized for MI (n=477) were recruited in three hospitals. The Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and questionnaires concerning PTSD symptoms and general measures were administered to patients during hospitalization and at one-month follow-up.

RESULTS:

Four per cent of the patients had PTSD and 12% had partial PTSD. The perception of a threat to life, the intensity of acute stress disorder and depression symptoms several days after the MI, a history of referral to a psychologist or psychiatrist, and female sex were risk factors for the intensity of PTSD symptoms in a sequential multiple regression analysis (R=0.634). The prediction model was validated by applying the regression equation to 48 participants who were not included in the initial regression (R=0.633).

CONCLUSIONS:

The risk factors for development of PTSD symptoms identified in the present study could be used to facilitate the detection of patients at risk for developing PTSD symptoms so they can later be offered psychological interventions as needed.     

Endoscopic Retrograde Cholangiopancreatography in Patients with Previous Acute Coronary Syndrome

Background/Aims

Endoscopic retrograde cholangiopancreatography (ERCP) is considered a high-risk procedure in patients with previous acute coronary syndrome (ACS); however, clinical studies are rare in the literature. The aim of this study was to investigate the safety and efficacy of ERCP in patients with previous ACS.

Methods

We retrospectively reviewed the medical records of patients with previous ACS who underwent ERCP between January 2007 and August 2012. The clinical characteristics, ERCP diagnoses, treatment results, and complications were analyzed.

Results

Fifty patients underwent ERCP an average of 41.6 months after ACS. The most common indication for ERCP was calculous cholangitis. After deep biliary cannulation, endoscopic sphincterotomy, biliary stone removal and endoscopic biliary drainage were successfully performed. Immediate postsphincterotomy bleeding occurred in seven patients, which was successfully controlled using endoscopic therapy. Elevation of cardiac troponin I levels were observed in three patients (6%) before ERCP, and all of these patients were diagnosed with pancreatobiliary disease combined with recurrent ACS, which was treated with coronary artery stent insertion (n=2) and balloon angioplasty (n=1).

Conclusions

Therapeutic ERCP is effective and safe in patients with previous ACS. Cardiac troponin I elevation should be considered a warning sign for recurrent ACS in patients who undergo ERCP.     

The use of retrievable inferior vena cava filters in the trauma population

OBJECTIVE:

To determine if the use of retrievable filters resulted in an increase in the placement of inferior vena cava (IVC) filters in trauma patients.

DESIGN:

All patients who underwent IVC filter placement at Yale-New Haven Hospital, New Haven, Connecticut, USA between the years 1999 and 2004.

SETTING:

Academic, level 1 trauma centre.

PATIENTS:

Included in the present study were 202 trauma patients and 676 nontrauma patients.

INTERVENTION:

IVC filter placement.

MAIN OUTCOME MEASURE:

Demographics, indications, complication rates and type of IVC filters placed in trauma patients versus nontrauma patients were evaluated.

RESULTS:

The present study determined 45.4% (n=92) of trauma patients undergoing IVC filter placement were younger than 40 years of age, compared with 7.8% (n=53) of nontrauma patients. The most common indication for IVC filter placement in trauma patients was prophylaxis (n=162, 80.2%), while in the nontrauma patients only 11.4% (n=77) of patients underwent prophylactic filter placement. The number of retrievable filters used in trauma patients increased from 46.7% in 2001, the year they became available, to 78.9% in 2004. The use of retrievable filters similarly increased in the nontrauma population from 35.9% in 2001 to 78.3% in 2004. Approximately 24% of the patients that underwent IVC filter placement at Yale-New Haven Hospital were categorized as trauma patients. The complication rate for this time period was 0.5% (n=1) in the trauma population versus 3.7% (n=26) in the nontrauma population.

CONCLUSION:

The overall number of IVC filters placed in trauma patients did not dramatically increase with the introduction of retrievable filters, suggesting that the indications for the use of IVC filters have not changed.     

Development of Magnetic Capture Hybridization and Quantitative Polymerase Chain Reaction for Hepatitis B Virus Covalently Closed Circular DNA

Background:

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) served as a vital role in the life cycle of the virus and persistent infection. However, specific and quantitative methods for cccDNA detection have not been available.

Objectives:

Our aim was to develop and primarily evaluate a quantitative method for HBV cccDNA based on magnetic capture hybridization and quantitative PCR technology.

Materials and Methods:

The functionalized-nanoparticles specifically to capture HBV cccDNA, located on both sides of relaxed circle DNA (rcDNA) gap, were designed. Then, magnetic capture hybridization and quantitative PCR (MCH-qPCR) assay were developed and its performance was primarily evaluated with cccDNA standards and serum samples of patients with chronic hepatitis B.

Results:

Specific nanoparticles of cccDNA capture were prepared and a magnetic capture hybridization and quantitative assay method for cccDNA was developed successfully. The limit of detection was 90 IU/mL, and a good linear relationship in the range of 10²-10⁶ IU/mL was revealed (r² = 0.994) with the MCH-qPCR. Compared with directly real-time PCR, a high content of HBV DNA did not affect the detection of cccDNA for the MCH-qPCR method, and there was no cross-reactivity between cccDNA and rcDNA.

Conclusions:

The novel MCH-qPCR method has good sensitivity and specificity. It could meet the requirement of clinical routine detection.     

Negative Association of Plasma Levels of Vitamin D and miR-378 With Viral Load in Patients With Chronic Hepatitis B Infection

Background:

Chronic Hepatitis B (CHB) is accompanied by inflammation of liver because of infection with Hepatitis B Virus (HBV). Previous studies revealed an inverse association between vitamin D and HBV DNA levels.

Objectives:

The current study aimed to investigate the levels of 25 (OH) D3 (the steady form of vitamin D), miR-378 and HBV DNA in the patients with CHB.

Patients and Methods:

One hundred and seventy three patients with HBeAg negative CHB were recruited for the study. Plasma levels of HBVDNA and 25 (OH) D3 were quantified. The expression level of miR-378 in plasma was measured by a relative quantitative Real Time Polymerase Chain Reaction (qRT-PCR) assay.

Results:

In the pathway regression analysis, the plasma level of 25 (OH) D3 showed a significant inverse correlation with plasma levels of HBV DNA (-0.198, P = 0.008) and direct correlation with miR-378 (0.188, P = 0.013). Similarly plasma level of miR-378 had inverse association with HBV DNA level (-0.177, P = 0.020).

Conclusions:

These results suggest that vitamin D could involve in a miRNA- mediated regulatory pathway in control of HBV replication. Further studies are recommended to understand the effects of miR-378 and anti-infective action of vitamin D on Hepatitis B Virus.     

Hemorrhagic cystitis after allogeneic hematopoietic stem cell transplants is the complex result of BK virus infection, preparative regimen intensity and donor type

Background

Hemorrhagic cystitis is a common cause of morbidity after allogeneic stem cell transplantation, frequently associated with BK virus infection. We hypothesized that patients with positive BK viruria before unrelated or mismatched related donor allogeneic hematopoietic stem cell transplantation have a higher incidence of hemorrhagic cystitis.

Design and Methods

To test this hypothesis, we prospectively studied 209 patients (median age 49 years, range 19–71) with hematologic malignancies who received bone marrow (n=78), peripheral blood (n=108) or umbilical cord blood (n=23) allogeneic hematopoietic stem cell transplantation after myeloablative (n=110) or reduced intensity conditioning (n=99). Donors were unrelated (n=201) or haploidentical related (n=8).

Results

Twenty-five patients developed hemorrhagic cystitis. Pre-transplant BK viruria detected by quantitative PCR was positive in 96 patients. The one-year cumulative incidence of hemorrhagic cystitis was 16% in the PCR-positive group versus 9% in the PCR-negative group (P=0.1). The use of umbilical cord blood or a haploidentical donor was the only significant predictor of the incidence of hemorrhagic cystitis on univariate analysis. There was also a trend for a higher incidence after myeloablative conditioning. Multivariate analysis showed that patients who had a positive PCR pre-transplant and received haploidentical or cord blood grafts with myeloablative conditioning had a significantly higher risk of developing hemorrhagic cystitis (58%) than all other recipients (7%, P<0.001).

Conclusions

Hemorrhagic cystitis is the result of a complex interaction of donor type, preparative regimen intensity, and BK viruria.     

HLA-DPB1 Variant Effect on Hepatitis B Virus Clearance and Liver Cirrhosis Development Among Southwest Chinese Population

Background:

Previous studies have shown that genetic variants in HLA-DP genes affect disease progression in hepatitis B virus (HBV) infection.

Objectives:

We aimed to evaluate possible association between HLA-DPB1 rs9277534 polymorphism and different clinical complications of hepatitis B virus (HBV) infection.

Materials and Methods:

Snapshot assay was used to investigate the association of rs9277534 polymorphism in 342 patients with persistent HBV infection and 342 age and gender-matched HBV spontaneous clearance controls. Patients were categorized into asymptomatic HBV carriers (AsC, n = 104), chronic hepatitis B (CHB, n = 116), and liver cirrhosis (LC, n = 122) subgroups.

Results:

There was a significantly higher proportion of the rs9277534 minor allele A in HBV spontaneous clearance control than that in HBV persistent infection group (OR = 0.58, 95%CI = 0.46-0.73, P < 0.0001). Genotypic analysis showed that GA and AA genotypes were associated with HBV spontaneous clearance (GA: OR = 0.56, 95%CI = 0.40-0.79, P = 0.019; AA: OR = 0.24, 95%CI = 0.14-0.44, P < 0.0001). A significant difference was found between AsC and LC groups in the distribution of AA genotype (OR = 9.32, 95%CI = 1.293-67.14, P = 0.027).

Conclusions:

Variant at rs9277534 could affect both the spontaneous clearance of HBV infection and progression from asymptomatic HBV carriers to HBV-related liver cirrhosis in Southwest Han Chinese population.     

Diagnostic usefulness of graded exercise testing in pediatric supraventricular tachycardia

BACKGROUND:

Episodic symptoms, often reported during exertion, complicate the assessment of suspected supraventricular tachycardia (SVT).

OBJECTIVE:

To examine the diagnostic sensitivity of graded exercise testing in young patients with documented SVT or ventricular pre-excitation.

METHODS:

A single-centre retrospective review identified 53 patients (5.1 to 17.5 years of age) with structurally normal hearts who had undergone 65 graded treadmill exercise tests in the setting of either documented SVT with normal resting electrocardiograms (n=30) or ventricular pre-excitation (n=23). Twenty-five patients (13 pre-excited and 12 nonpre-excited) had exercise-related symptoms. SVT induction during exercise testing was assessed in relation to pre-excitation and the patient’s history of exercise-induced symptoms.

RESULTS:

SVT was induced during six of the 65 exercise tests performed in three of 53 patients (overall sensitivity 5.7%). All three patients had a history of exercise-induced symptoms, and two had ventricular pre-excitation. SVT was induced in 12% of patients with exercise-related symptoms. No other rhythm disturbances occurred during exercise testing.

CONCLUSION:

The diagnostic yield of graded exercise testing in patients with suspected SVT is limited, even among those with exercise-related symptoms.     

Routine pretreatment with abciximab versus standard periprocedural therapy in mechanically ventilated cardiogenic shock patients undergoing primary percutaneous coronary intervention: Subanalysis of the PRAGUE-7 study

BACKGROUND:

The clinical outcome of patients with myocardial infarction (MI) complicated by cardiogenic shock (CS) who require mechanical ventilation (MV) is poor.

OBJECTIVE:

To analyze the impact of abciximab pretreatment in this high-risk population of MI patients.

METHODS:

The present study was a retrospective subanalysis of the multicentre randomized Routine Upfront Abciximab Versus Standard Peri-Procedural Therapy in Patients Undergoing Percutaneous Coronary Intervention for Cardiogenic Shock (PRAGUE-7) study, which included 80 MI patients in CS undergoing primary percutaneous coronary intervention (PCI). Patients were randomly assigned into group A (routine pretreatment with an abciximab bolus followed by a 1 h abciximab infusion) and group B (standard therapy). The subanalysis included 37 patients requiring MV. Seventeen patients were in group A and 20 were in group B. The primary end point (death/stroke/reinfarction/new severe renal failure) at 30 days, procedural success (thrombosis in myocardial infarction [TIMI] flow) and frequency of bleeding were assessed. The χ² and Student’s t tests were used for statistical analysis; P<0.05 was considered to be statistically significant.

RESULTS:

The primary end point occurred in nine (53%) patients in group A and 12 (60%) patients in group B (P=0.66). TIMI flow after primary PCI was higher in group A (2.75 versus 2.31; P<0.05). Major bleeding occurred in 12% of patients in group A versus 10% of patients in group B (P=0.86). Minor or minimal bleeding was more common in group A (29%) compared with group B (5%; P<0.05).

CONCLUSION:

The results of the present study suggest that routine pretreatment with abciximab before primary PCI in mechanically ventilated patients with MI complicated by cardiogenic shock was associated with better angiographic results but also with a higher incidence of bleeding.     

Levels of troponin release can aid in the early exclusion of stress-induced (takotsubo) cardiomyopathy

BACKGROUND:

Stress-induced cardiomyopathy is usually associated with an increased level of cardiac enzymes, leading to difficulties in differentiating this condition from acute coronary syndrome. The final diagnosis is usually made based on angiographic findings revealing normal coronary arteries. It was hypothesized that maximal cardiac enzyme elevation in these patients should have an upper limit. In the present study, reported cases of stress cardiomyopathy were compared with documented cardiac enzyme levels to evaluate the upper cut-off point of troponin in this population.

METHOD:

All of the articles published in PubMed and MEDLINE from November 2007 to July 2008, on takotsubo or stress-induced cardiomyopathy, were identified. Only the cases that reported the absolute or mean level of cardiac enzymes were included. The level of various enzymes were correlated with cardiac function, and the upper limit of enzyme elevation was calculated in these patients.

RESULTS:

A total of 114 patients (mean [± SD] age 63.5±14.5 years) were included in the study. Seventy-one per cent of the patients were older than 50 years of age and 86% were female. Mean values for troponin I, troponin T, creatine kinase (CK) and CK-MB were 6.5 ng/mL, 3.6 ng/mL, 556 U/L and 32.9 U/L, respectively. All of the patients with takotsubo cardiomyopathy had a troponin T level of 6 ng/mL or less and troponin I level of 15 ng/mL or less. Troponin T showed a significant inverse correlation with initial ejection fraction (R²=0.6), which was not seen with the levels of troponin I, CK and CK-MB. Takotsubo cardiomyopathy was classified as classic (66.7%), mid-cavitary (10%), reverse (23.3%) or local (0%).

CONCLUSION:

Among patients with takotsubo cardiomyopathy, troponin T level correlated with initial ejection fraction. Furthermore, the diagnosis of takotsubo cardiomyopathy appears to be unlikely in patients with troponin T greater than 6 ng/mL or troponin I greater than 15 ng/mL.     

Cardiotrophin-1 promotes cardiomyocyte differentiation from mouse induced pluripotent stem cells via JAK2/STAT3/Pim-1 signaling pathway

Background The induced pluripotent stem cell (iPSC) has shown great potential in cellular therapy of myocardial infarction (MI), while its application is hampered by the low efficiency of cardiomyocyte differentiation. The present study was designed to investigate the effects of cardiotrophin-1 (CT-1) on cardiomyocyte differentiation from mouse induced pluripotent stem cells (miPSCs) and the underlying mechanisms involved. Methods The optimal treatment condition for cardiomyocyte differentiation from miPSCs was established with ideal concentration (10 ng/mL) and duration (from day 3 to day 14) of CT-1 administration. Up-regulated expression of cardiac specific genes that accounted for embryonic cardiogenesis was observed by quantitative RT-PCR. Elevated amount of α-myosin heavy chain (α-MHC) and cardiac troponin I (cTn I) positive cells were detected by immunofluorescence staining and flow cytometry analysis in CT-1 group. Results Transmission electron microscopic analysis revealed that cells treated with CT-1 showed better organized sacromeric structure and more mitochondria, which are morphological characteristic of matured cardiomyocytes. Western blot demonstrated that CT-1 promotes cardiomyocyte differentiation from miPSCs partly via JAK2/STAT3/Pim-1 pathway as compared with control group. Conclusions These findings suggested that CT-1 could enhance the cardiomyocyte differentiation as well as the maturation of mouse induced pluripotent stem cell derived cardiomyocytes by regulating JAK2/STAT3/Pim-1signaling pathway.     

Surgical management of acute necrotizing lung infections

BACKGROUND:

Surgical resection for acute necrotizing lung infections is not widely accepted due to unclear indications and high risk.

OBJECTIVE:

To review results of resection in the setting of acute necrotizing lung infections.

METHODS:

A retrospective review of patients who underwent parenchymal resection between January 1, 2000, and January 1, 2006, for management of necrotizing pneumonia or lung gangrene.

RESULTS:

Thirty-five patients underwent resection for lung necrosis. At the time of consultation, all patients presented with pulmonary sepsis, and also had the following: empyema (n=17), hemoptysis (n=5), air leak (n=7), septic shock requiring pressors (n=8) and inability to oxygenate adequately (n=7). Twenty-four patients were ventilated pre-operatively. Eleven patients had frank lobar gangrene, and the other patients had combinations of necrotizing pneumonia and abscesses. In 10 patients, preresection procedures were performed, including percutaneous drainage of an abscess (n=4), thoracoscopic decortication (n=4) and open decortication (n=2). Procedures included pneumonectomy (n=4), lobectomy (n=18), segmentectomy (n=2), wedge resection (n=4) and debridement (n=7). There were three (8.5%) postoperative deaths – two due to multiple organ failure and one due to anoxic brain injury. All patients not ventilated preoperatively were weaned from ventilatory support within three days. Of those ventilated preoperatively, three died, while four remained chronically ventilator dependent.

CONCLUSIONS:

Surgical resection for necrotizing lung infections is a reasonable option in patients with persistent sepsis who are failing medical therapy. Ventilated patients have a worse prognosis but can still be candidates for resection. Patients who are hemodynamically unstable appear to have better outcomes if they can be stabilized before resection.     

Complementary prognostic values of ST segment deviation and Thrombolysis In Myocardial Infarction (TIMI) risk score in non-ST elevation acute coronary syndromes: Insights from the Platelet Receptor Inhibition in Ischemic Syndrome Management in Patients Limited by Unstable Signs and Symptoms (PRISM-PLUS) study

BACKGROUND:

Although the Thrombolysis In Myocardial Infarction (TIMI) score incorporates ST deviation, it does not account for characteristics of the ST deviations. In the present study, it was hypothesized that the magnitude and characteristics of ST deviation may add to the prognostic values of the TIMI risk score in acute coronary syndrome (ACS) patients, particularly in lower-risk patients with a TIMI risk score of less than 5.

OBJECTIVE:

To evaluate the prognostic value of combining the TIMI risk score and characteristics of ST deviation in patients with non-ST elevation ACS and a TIMI risk score of less than 5.

METHODS:

The death/myocardial infarction (MI) rates of 1296 patients enrolled in the Platelet Receptor Inhibition in Ischemic Syndrome Management in Patients Limited by Unstable Signs and Symptoms (PRISM-PLUS) angiographic substudy were examined.

RESULTS:

Patients without a TIMI risk score of 5 or greater, and without an ST deviation of 1 mm or greater had the lowest six-month rate of death/MI (5%). In patients with a TIMI risk score of less than 5, the six-month death/MI rate was increased in those with ST depression of 2 mm or greater compared with patients with a similar TIMI risk score and without ST deviation of 1 mm or greater (24% versus 5%, P<0.001). The presence of ST deviation of 2 mm or greater identified an additional 15% of patients with an increased six-month death/MI rate in patients with a TIMI risk score of less than 5.

CONCLUSION:

ST segment deviation of 2 mm or greater confers additional prognostic information in non-ST elevation ACS patients with a TIMI risk score of less than 5. Patients with a TIMI risk score of less than 5 and ST deviation of 2 mm or less had the lowest risk of six-month death/MI.     

Management of necrotizing pneumonia and pulmonary gangrene: A case series and review of the literature

BACKGROUND:

Necrotizing pneumonia is an uncommon but severe complication of bacterial pneumonia, associated with high morbidity and mortality. The availability of current data regarding the management of necrotizing pneumonia is limited to case reports and small retrospective observational cohort studies. Consequently, appropriate management for these patients remains unclear.

OBJECTIVE:

To describe five cases and review the available literature to help guide management of necrotizing pneumonia.

METHODS:

Cases involving five adults with respiratory failure due to necrotizing pneumonia admitted to a tertiary care centre and infected with Streptococcus pneumoniae (n=3), Klebsiella pneumoniae (n=1) and methicillin-resistant Staphylococcus aureus (n=1) were reviewed. All available literature was reviewed and encompassed case reports and retrospective reviews dating from 1975 to the present.

RESULTS:

All five patients received aggressive medical management and consultation by thoracic surgery. Three patients underwent surgical procedures to debride necrotic lung parenchyma. Two of the five patients died in hospital.

CONCLUSIONS:

Necrotizing pneumonia often leads to pulmonary gangrene. Computed tomography of the thorax with contrast is recommended to evaluate the pulmonary vascular supply. Further study is necessary to determine whether surgical intervention, in the absence of pulmonary gangrene, results in better outcomes.     

Safety of esophagogastroduodenoscopy within 30 days of myocardial infarction: a retrospective cohort study from a Canadian tertiary centre

BACKGROUND:

Patients who experience myocardial infarction (MI) are at risk of gastrointestinal (GI) bleeding complications. Endoscopic evaluation may lead to cardiopulmonary complications. Guidelines and studies regarding the safety of endoscopy in this population are limited.

OBJECTIVE:

To evaluate the safety of endoscopy in a retrospective cohort of post-MI patients at a Canadian tertiary centre.

METHODS:

Using hospital diagnostic/procedure codes, the charts of patients meeting the inclusion criteria of having ST elevation MI or non-ST elevation MI, and GI bleeding detected at endoscopy were reviewed. The information retrieved included demographics, medical history, medications, endoscopy details and cardiopulmonary/GI events.

RESULTS:

A total of 121 patients experienced an MI and underwent endoscopy within 30 days. However, only 44 met the inclusion criteria and were reviewed. The mean age of the patients was 75 years, and 55% were female. The mean hemoglobin level was 86 g/L, and 38 of 44 patients required a transfusion. Comorbidities included hypertension (82%), diabetes (46%), heart failure (55%), stroke (21%), lung disease (27%), previous MI (46%), cardiac bypass surgery (30%), history of GI bleed (25%), history of ulcer (18%) and ejection fraction <50% (48%). The median number of days to endoscopy after MI was three. Complications included seven patients with acute coronary syndrome, one with arrhythmia, one with respiratory failure, one with aspiration pneumonia and two with perforation. Age, hemoglobin level or timing of endoscopy did not significantly predict a complication.

CONCLUSIONS:

Patients with GI bleeding after MI often have comorbidities and are on antiplatelet agents. Endoscopy is a valuable tool in the diagnosis and management of bleeding complications, but must be weighed against the potential risk of other complications, which in the present study occurred in more than 25% of procedures.     

Impact of the troponin standard on the prevalence of acute myocardial infarction

Background

Recent recommendations are that troponin should replace creatine kinase (CK)-MB as the diagnostic standard for myocardial infarction (MI). The impact of this change has not been well described. Our objective was to determine the impact of a troponin standard on the prevalence of acute non-ST-elevation MI.

Methods

The current study was a retrospective analysis of consecutive patients without ST-segment elevation admitted for exclusion of myocardial ischemia to an inner city urban tertiary care center. All patients underwent serial marker sampling (CK, CK-MB, and cardiac troponin I [cTnI]). Patients with ST elevation consistent with acute MI (n = 130) or who did not have an 8 hour cTnI (n = 124) were excluded. The impact of 3 different cTnI diagnostic values were examined in 2181 patients: the lower limit of detectability (LLD); an optimal diagnostic value (OPT), chosen using receiver operator characteristic curve analysis; and the manufacturer's suggested upper reference level (URL), when compared to a gold standard CK-MB MI definition. In addition, MI prevalence was assessed using different CK-MB MI definitions and evaluated in patients with ischemic changes only.

Results

The prevalence CK-MB MI was 7.8%. Using the various cTnI diagnostic values, the incidence of MI increased the prevalence by 28% to 195%. Using the optimal diagnostic value for cTnI, patients with cTnI elevations not meeting CK-MB MI criteria had an intermediate 30-day mortality (5.4%) compared to those with CK-MB MI (7.1%). Grouping the cTnI positive, CK-MB MI negative patients with the CK-MB MI patients rather than the non-CK-MB MI patients reduced mortality for both the MI (to 5.9%) and non-MI groups (from 1.9% to 1.6%).

Conclusions

Changing to a troponin standard will have a substantial impact on the number of patients diagnosed with MI. The revised definition for MI will have important clinical and health care implications.     

Diagnostic yield of repeat capsule endoscopy and the effect on subsequent patient management

BACKGROUND:

Capsule endoscopy (CE) has been shown to produce a high diagnostic yield in patients with obscure gastrointestinal bleeding (OGIB); however, in those with negative studies, management is controversial. Very few studies have reported on repeat CE in the same patient; data regarding this diagnostic strategy are limited.

OBJECTIVE:

To determine the diagnostic yield of repeated CE studies and how this yield affects subsequent patient management.

METHODS:

A retrospective chart review of all patients who underwent CE at St Paul’s Hospital (Vancouver, British Columbia) between December 2001 and June 2009 was conducted. Patients who underwent subsequent repeat CE were identified and divided into one of four subgroups. Findings were classified as positive or negative.

RESULTS:

Eighty-two of 676 patients underwent more than one CE study. Group 1 (incomplete study) included 22 patients (27%) and yielded 10 positive findings (45%). Group 2 (screening) comprised four patients (5%) and yielded two positive findings (50%). Group 3 (ongoing symptoms despite previous negative study) totalled 26 patients (32%) and yielded 10 positive findings (38%). Group 4 (previous positive study with treatment/investigation) included 30 patients (37%) and yielded 23 positive findings (77%). Overall, the present study found positive findings in 55% (45 of 82) of repeated CE cases, which resulted in a change in management in 39% (n=32) of the patients.

CONCLUSION:

Due to the high diagnostic yield and noninvasive nature of CE, repeat CE appears to be of benefit and should be considered for specific patients before other types of small bowel studies.     

Relationship between accessory pathway location and occurrence of atrial fibrillation in patients with atrioventricular re-entrant tachycardia

OBJECTIVE:

To study the relationship between the location of atrioventricular accessory pathways and occurrence of atrial fibrillation (AF) in patients with atrioventricular re-entrant tachycardia (AVRT).

METHODS:

The clinical features and location of accessory pathways in patients with a history of AF were compared with those of patients with no history of AF.

RESULTS:

Patients with AF (n=44) were older, more likely to be male and more likely to have multiple or manifest accessory pathways than patients without AF (n=373). There was no significant difference in the location of accessory pathways between the two groups. Multivariate regression analysis showed older age, male sex, and multiple and manifest pathways were independent predictors of AF in patients with AVRT (P<0.01).

CONCLUSIONS:

The location of accessory pathways does not appear to play a critical role in the pathogenesis of AF in patients with AVRT. Older patients with multiple or manifest accessory pathways are at an increased risk of clinical AF.