Failure of diltiazem to prevent 1:1 conduction of atrial flutter: a case report

BACKGROUND

Atrial flutter with 1:1 conduction to the ventricles is a dangerous cardiac arrhythmia. Contemporary guidelines recommend atrioventricular nodal blocking agents should be co-administered with class 1C anti-arrhythmics, as prophylaxis against 1:1 flutter. No guidance is provided on the type or strength of atrioventricular nodal blockade required, and in practice, these agents are frequently prescribed at low dose, or even omitted, due to their side effect profile.

CASE PRESENTATION

A 62 year old Caucasian man with a history of paroxysmal atrial fibrillation treated with flecainide, presented with atrial flutter with 1:1 conduction to the ventricles and was cardioverted. Diltiazem was added to prevent this complication and he again presented with atrial flutter with 1:1 conduction to the ventricles, despite prophylaxis with coadministration of diltiazem.

CONCLUSIONS

This case report demonstrates failure of diltiazem to prevent 1:1 flutter in a patient chronically treated with flecainide for paroxysmal atrial fibrillation.

Vomiting, electrolyte disturbance, and medications; the perfect storm for acquired long QT syndrome and cardiac arrest: a case report

Background

Acquired long QT syndrome is an important and preventable cause of cardiac arrest. Certain medications and electrolyte disturbance are common contributors, and often coexist. In this case, we report five contributors to cardiac arrest.

Case presentation

This case is of a 51-year-old Caucasian female patient who presented with vomiting associated with hypokalemia and hypomagnesemia. She subsequently received ondansetron and metoclopramide, on the background of chronic treatment with fluoxetine. She then suffered an in-hospital monitored cardiac arrest, with features of long QT and torsades de pointes retrospectively noted on her prearrest electrocardiogram. She was diagnosed with acquired long QT syndrome, and her QT interval later normalized after removal of offending causes.

Conclusions

This case highlights the importance of proper consideration prior to prescribing QT prolonging medications, especially in patients who have other risk factors for prolonged QT, such as electrolyte disturbances and pretreatment with QT prolonging medications.

807 A Review of The Applications of Autologous Fascia Lata Grafts in Reconstructive Surgery

Background

We sought to review current applications of fascia lata autografts and update the original collection of uses proposed almost a century ago, thereby revealing the full extent of uses available to the contemporary reconstructive surgeon.

Method

A comprehensive literature search of peer-reviewed articles listed within PubMed and Medline was performed.

Results

The properties of autologous fascia lata grafts are presented, a technique for its harvest and the numerous uses of this material in reconstructive surgery. Specifically, its applications in head and neck surgery, surgery of the limbs, abdominal wall reconstruction and penile reconstruction are reviewed.

There is limited data on donor site morbidity, but complications appear to be uncommon. However, it was established that the reported risk of muscle herniation varies greatly in the available literature from 0-36% and appears to be related to the width of tissue harvested.

Conclusions

Autologous fascia lata grafts are a viable and versatile material in the armamentarium of a reconstructive surgeon, that, with careful planning, can be used with minimal donor site morbidity. This is especially true in lower resource settings where a surgeon may not have access to allogenic material and autologous grafts can provide an easily accessible, cheaper, and practical alternative.

Observational study comparing pharmacoinvasive strategy with primary percutaneous coronary intervention in patients presenting with ST elevation myocardial infarction to a tertiary care centre in India

Objective:

The objective was to study whether the incidence of composite end points (mortality, cardiogenic shock and re-myocardial infarction [re-MI]) in pharmacoinvasive strategy was noninferior to primary percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI).

Methods:

This was an observational study which included 138 patients. The study included patients admitted with a diagnosis of STEMI within 24 h of symptom onset, who underwent primary PCI or pharmacoinvasive therapy in a single center over a 9-month period. Primary end points (death within 30 days, re-MI within 30 days, and cardiogenic shock) and secondary end points (arrhythmias, bleeding manifestations, ischemic stroke, ejection fraction, mechanical complications, and duration of hospital stay) were compared between the two groups at 1 month after intervention.

Results:

At one month follow-up, the incidence rate for primary end points was 5 events per 43 patients (11.6%) in pharmacoinvasive arm and 18 events per 95 patients (18.9%) in primary PCI arm, a difference of - 7.3% (95% confidence interval: 18.5, 7.1). This finding shows that pharmacoinvasive strategy as compared with primary PCI in the management of STEMI was equivalent in terms of composite primary outcome. There was no significant difference between the secondary outcomes between the two groups. Use of thrombus aspiration device and in turn the thrombus burden was significantly lower in the pharmacoinvasive arm.

Conclusion:

This observational study showed that pharmacoinvasive strategy was as good as primary PCI in STEMI, in our setting, where primary PCI may be delayed or not possible at all due to financial and logistic constraints.

Leveraging the private sector for child health: a qualitative examination of caregiver and provider perspectives on private sector care for childhood pneumonia in Uttar Pradesh, India

BACKGROUND

The private health sector is a primary source of curative care for childhood illnesses in many low- and middle-income countries. Therefore ensuring appropriate private sector care is an important step towards improving outcomes from illnesses like pneumonia, which is the leading infectious cause of childhood mortality worldwide. This study aimed to provide evidence on private sector care for childhood pneumonia in Uttar Pradesh, India, by simultaneously exploring providers' knowledge and practices and caregivers' experiences.

METHODS

We conducted in-depth interviews with a purposive sample of 36 practitioners and 34 caregivers in two districts. Practitioners included allopathic doctors, AYUSH providers, and drug sellers. Caregivers were mothers of children under the age of five with symptoms consistent with pneumonia who had seen one of those practitioners. Interview transcripts were analyzed thematically.

RESULTS

Caregivers were generally prompt in seeking care outside the home, but many initially favored local informal providers based on access and cost. Drug sellers were not commonly consulted for treatment. Formal providers had imperfect, but reasonable, knowledge of pneumonia and followed appropriate steps for diagnosis, though some gaps were noticed that were primarily related to lack of (or failure to use) diagnostic tools. Most practitioners prescribed antibiotics and supportive symptomatic treatment. Relational and structural factors encouraged overuse of antibiotics and treatment interruption. Caregivers often had a limited understanding of treatment but wanted rapid symptomatic improvements, frequently leading to sequentially consulting multiple providers and interrupting treatment when symptoms improved. Providers were confronted with these expectations and care-seeking patterns.

CONCLUSIONS

This study contributes in-depth evidence on private sector care for childhood pneumonia in UP. Achieving appropriate care requires an enriched perspective that simultaneously considers the critical role of provider-caregiver interactions and of the context in which they occur in shaping treatment outcomes.

Evaluation of N-terminal pro-B type natriuretic peptide analysis on the ElecsysTM 1010 and 2010 analysers

Background: N-terminal pro-B type natriuretic peptide (NTpBNP) is a potential marker of cardiac failure.

Methods: The Roche ElecsysTM 1010 and 2010 assays for NTpBNP were evaluated for precision, sample stability, and correlation between sample types and with other natriuretic peptides. Samples from 290 individuals aged 45-89 years with no cardiovascular risk factors, renal failure, electrocardiogram changes, evidence of structural abnormalities, or wall motion abnormalities on echocardiography and with an ejection fraction >50% were used to provide reference NTpBNP ranges.

Results: The intra-assay imprecision was <10% across the analytical range and >3% at all concentrations analysed <30 ng/L. Inter-assay imprecision was 5.3-6.7% on the Elecsys 1010 and 4.4-5.0% on the Elecsys 2010, in the range 380-13000 ng/L. There was no statistically significant change in NTpBNP following storage in whole-blood samples at room temperature for 24 h before centrifugation; serum samples at room temperature for 7 days, at 4°C for up to 11 days on clot-activation gel or 22 days separated from the gel. NTpBNP concentrations were stable throughout five freeze-thaw cycles. There was a close correlation between NTpBNP concentrations in matched serum, EDTA plasma and lithium-heparin plasma samples. NTpBNP and BNP were more closely associated than were N-terminal proatrial natriuretic peptide and NTpBNP. This association was stronger at lower concentrations. NTpBNP concentrations increased with age, with values higher in women than men.

Conclusions: NTpBNP is a stable molecule that can be measured easily and precisely using the Roche Elecsys 1010 or 2010 immunoassay analysers.

Deep neural ensemble for retinal vessel segmentation in fundus images towards achieving label-free angiography

Automated segmentation of retinal blood vessels in label-free fundus images entails a pivotal role in computed aided diagnosis of ophthalmic pathologies, viz., diabetic retinopathy, hypertensive disorders and cardiovascular diseases. The challenge remains active in medical image analysis research due to varied distribution of blood vessels, which manifest variations in their dimensions of physical appearance against a noisy background. In this paper we formulate the segmentation challenge as a classification task. Specifically, we employ unsupervised hierarchical feature learning using ensemble of two level of sparsely trained denoised stacked autoencoder. First level training with bootstrap samples ensures decoupling and second level ensemble formed by different network architectures ensures architectural revision. We show that ensemble training of auto-encoders fosters diversity in learning dictionary of visual kernels for vessel segmentation. SoftMax classifier is used for fine tuning each member autoencoder and multiple strategies are explored for 2-level fusion of ensemble members. On DRIVE dataset, we achieve maximum average accuracy of 95.33% with an impressively low standard deviation of 0.003 and Kappa agreement coefficient of 0.708. Comparison with other major algorithms substantiates the high efficacy of our model.

Abundance of Mycobacterium avium ssp. hominissuis in soil and dust in Germany - implications for the infection route

The nontuberculous mycobacteria (NTM) are a heterogeneous group of bacteria found in soil, water and dust. The spread of NTM infection depends on the exposure to reservoirs with high proportions of mycobacteria, the virulence of the NTM strains, the enhanced sensitivity to infections such as those of immune-compromised hosts and patient risk factors such as Cystic Fibrosis. Since several decades, NTM lung disease has been increasingly observed in slender postmenopausal women. The most important NTM in Germany is Mycobacterium avium ssp. hominissuis (MAH). The routes of MAH infection are in almost all cases unknown, but water is often suspected as source of infection. We wanted to examine this hypothesis by determining the frequency of MAH in environmental samples of water, biofilms, soil and dust originating from Germany. We found MAH in 33% of the dust samples and 20% of the soil samples. No MAH could be isolated from water and biofilm. Dust and soil clearly presented more abundance of MAH in comparison with water and biofilms. Therefore, more attention should be paid to soil and dust in Germany as an important source of Myco. avium infections.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study was conducted to investigate the ecological abundance of the most prominent clinical nontuberculous mycobacteria (NTM) in Germany, the Mycobacterium avium ssp. hominissuis (MAH). Examination of soil, water, dust and biofilm samples revealed that MAH in Germany was predominant in soil and dust. No MAH was identified in water and biofilms. Our finding contributes to the identification of the environmental niche of this opportunistic pathogen and proposes soil and dust as sources of MAH infection in Germany.

Penile degloving: an unusual presentation of hidradenitis suppurativa

Chronic hidradenitis suppurativa (HS) can cause lymphoedema, leading to novel presentations. We present the case of a man with chronic HS causing penile oedema and subsequent degloving. He underwent direct excision with a good result. Chronic HS patients should be warned about problems related to lymphoedema and reviewed regularly to resolve problems early.

High levels of IgM against methylglyoxal-modified apolipoprotein B100 are associated with less coronary artery calcification in patients with type 2 diabetes

OBJECTIVE

  Advanced glycation end products (AGE) have been implicated in diabetic vascular complications through activation of pro-inflammatory genes. AGE-modified proteins are also targeted by the immune system resulting in the generation of AGE-specific autoantibodies, but the association of these immune responses with diabetic vasculopathy remains to be fully elucidated. The aim of this study was to determine whether antibodies against apolipoprotein B100 modified by methylglyoxal (MGO-apoB100) are associated with coronary atherosclerosis in patients with type 2 diabetes.

METHODS

  We measured antibodies against MGO-apoB100 in plasma from 497 type 2 diabetic patients without clinical signs of cardiovascular disease. Severity of coronary disease was assessed as coronary artery calcium (CAC) imaging. Immunoglobulin (Ig)M and IgG levels recognizing MGO-apoB100 were determined by enzyme-linked immunosorbent assay.

RESULTS

  Anti-MGO-apoB100 IgM antibody levels were higher in subjects with a low to moderate CAC score (≤400 Agatston units) than in subjects with a high score (>400 Agatston units; 136.8±4.4 vs. 101.6± 7.4 arbitrary units (AU), P<0.0001) and in subjects demonstrating no progression of CAC during 30 months of follow-up (136.4±5.7 vs. 113.9 ± 6.2 AU in subjects with progression, P<0.0001). Subjects with a family history of premature myocardial infarction had lower levels of anti-MGO-apoB100 IgM. Female subjects had higher levels of anti-MGO-apoB100 antibodies and lower CAC than men. Accordingly, high levels of IgM against MGO-apoB100 are associated with less severe and a lower risk of progression of coronary disease in subjects with type 2 diabetes.

CONCLUSIONS

Although conclusions regarding causal relationships based on epidemiological observations need to be made with caution, our findings suggest the possibility that anti-MGO-apoB100 IgM may be protective in diabetic vasculopathy.

Comparative analysis of abscisic acid-regulated transcriptomes in Arabidopsis

Transcription regulation by the phytohormone abscisic acid (ABA) plays a key role in responses to various stresses and has been extensively studied in Arabidopsis thaliana using different expression analysis techniques. Previous studies on comparative analysis of expression regulation by ABA and ABA-related stresses demonstrated marked differences in the targets of ABA. However, as few expression experiments were available during these studies, they encompass only a subset of ABA-regulated genes. The aim of the present work was to compare gene expression regulated by ABA administration in a wider range of expression experiments. Despite diversity in the actual set of genes regulated by ABA, all ABA-regulated transcriptomes shared some basic features, such as a common induced gene set, common functional targets and involvement of common regulatory mechanisms. Moreover, the cis-regulatory architecture of genes belonging to this set is expected to be of interest because of their sensitivity to ABA and apparent independence from other experimental variables. Comparative analysis of cis-regulatory element (CRE) enrichment also identified a novel CRE that is strongly associated with ABA signalling-mediated transcription repression.

Hand washing practices in urban and rural communities in and around Kolkata, West Bengal

BACKGROUND

Public health importance of hand washing was known since 19th century. Many researchers also highlighted how hand washing could bring down the incidence of diarrhea, ARI & other diseases.

OBJECTIVE

To find out the extent of hand washing as practiced by the community, to what extent suggested steps of hand washing was followed and to assess the changes in bacteriological count of hand before and after hand washing.

METHOD

A community based cross sectional study was carried out during January-February 2007 among 161 respondents in and around Kolkata through interview, observation of hand washing in some situations as well as carrying out microbiological test.

RESULT

100% respondents interviewed practiced hand washing after defecation either with soap (59%) or with plain water, ash & mud (41%). But 64%, 51.6% and only 21.7% practiced hand washing before preparation of food; after using urinals; after changing the babies' nappies and disposing their feces respectively. Only 16.1% respondents washed their hands as per the recommended time of 15-30 seconds. Majority (75%) dried hands with apparently unclean materials. 90.7% followed step1 but none followed all the steps. Swab collection before and after hand washing revealed a decrease in colony count in 60% of the samples.

CONCLUSION

It can be concluded that extent of desirable practices regarding hand washing is still lacking and needs to be emphasized.

Associations between autoantibodies against apolipoprotein B-100 peptides and vascular complications in patients with type 2 diabetes

AIMS/HYPOTHESIS

Oxidation of LDL in the arterial extracellular matrix is a key event in the development of atherosclerosis and autoantibodies against oxidised LDL antigens reflect disease severity and the risk of developing acute cardiovascular events. Since type 2 diabetes is associated with increased oxidative stress, we tested the hypothesis that autoantibodies against oxidised LDL antigens are biomarkers for vascular complications in diabetes.

METHODS

We studied 497 patients with type 2 diabetes without clinical signs of coronary heart disease. Oxidised LDL autoantibodies were determined by ELISA detecting IgG and IgM specific for native and malondialdehyde (MDA)-modified apolipoprotein B-100 peptides p45 and p210. The severity of coronary disease was assessed as the coronary artery calcium score.

RESULTS

Patients affected by retinopathy had significantly higher levels of IgG against MDA-p45 and MDA-p210. In contrast, high levels of autoantibodies against the corresponding native peptides were associated with less coronary calcification and a lower risk of progression of coronary disease.

CONCLUSIONS/INTERPRETATION

Our observations suggest that LDL oxidation is involved in the pathogenesis of diabetic retinopathy and that autoantibodies against apolipoprotein B peptides may act as biomarkers for both micro- and macrovascular complications in diabetes.

Interactions of HIPPI, a molecular partner of Huntingtin interacting protein HIP1, with the specific motif present at the putative promoter sequence of the caspase-1, caspase-8 and caspase-10 genes

To investigate the mechanism of increased expression of caspase-1 caused by exogenous Hippi, observed earlier in HeLa and Neuro2A cells, in this work we identified a specific motif AAAGACATG (- 101 to - 93) at the caspase-1 gene upstream sequence where HIPPI could bind. Various mutations in this specific sequence compromised the interaction, showing the specificity of the interactions. In the luciferase reporter assay, when the reporter gene was driven by caspase-1 gene upstream sequences (- 151 to - 92) with the mutation G to T at position - 98, luciferase activity was decreased significantly in green fluorescent protein-Hippi-expressing HeLa cells in comparison to that obtained with the wild-type caspase-1 gene 60 bp upstream sequence, indicating the biological significance of such binding. It was observed that the C-terminal 'pseudo' death effector domain of HIPPI interacted with the 60 bp (- 151 to - 92) upstream sequence of the caspase-1 gene containing the motif. We further observed that expression of caspase-8 and caspase-10 was increased in green fluorescent protein-Hippi-expressing HeLa cells. In addition, HIPPI interacted in vitro with putative promoter sequences of these genes, containing a similar motif. In summary, we identified a novel function of HIPPI; it binds to specific upstream sequences of the caspase-1, caspase-8 and caspase-10 genes and alters the expression of the genes. This result showed the motif-specific interaction of HIPPI with DNA, and indicates that it could act as transcription regulator.

Hypoplastic thumb in Gorlin's syndrome

Gorlin's syndrome or naevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder that predisposes to basal cell carcinomas of the skin, ovarian fibromas, and medulloblastomas. This condition is due to mutations in the Patched (PTCH) gene which maps to chromosome 9q22 and acts as a tumour suppressor gene. Gorlin's syndrome is characterized by the development of multiple jaw keratocysts and/or basal carcinomas. There is a distinctive coarse facial appearance with macrocephaly, frontal bossing and prognathism. Most individuals have skeletal anomalies such as bifid ribs or wedge-shaped vertebrae. We present a case in which the patient presented with bilateral thumb hypoplasia. Various hand deformities have been reported in patients with Gorlin's syndrome including short metacarpals, cutaneous syndactyly of the second and third fingers, and pre- or post-axial polydactyly, but hypoplasia of the thumb has not been reported previously. These features of Gorlin's syndrome may be helpful diagnostically. The thumbs should be examined carefully in Gorlin's syndrome patients as minor degrees of hypoplasia are easy to miss. However, they still needs a specialist input to give the patient an optimum function of the thumb and the hand.

Breast reconstruction using deep inferior epigastric perforator flaps in EEC syndrome

Ectrodactyly, ectodermal dysplasia, cleft lip/palate (EEC) syndrome is a rare condition that may result in failure of breast development. Breast reconstruction in these patients may pose a challenging problem, as they are young and reconstructive options should have minimal long-term complications. The use of deep inferior epigastric perforator (DIEP) flaps in breast reconstruction following breast cancer has been well described with good results. The use of DIEP flaps in breast augmentation, however, is far less common. We present the case of a young patient with EEC syndrome and mammary hypoplasia who underwent DIEP flap reconstruction for breast augmentation. The outcome was satisfactory to both patient and surgeon.

Diagnostic and prognostic role of cardiac troponin I (cTnI) measured on the DPC Immulite

OBJECTIVE

To evaluate the diagnostic and prognostic role of the Immulite cTnI assay for the detection of acute coronary syndromes (ACS).

POPULATION

150 males and 63 females with a median age of 63 years, range 28 to 88, and an interquartile range of 18 years were admitted within 24 h of chest pain and non-ST segment elevation ACS were studied. The median onset of symptoms was 3 h (range 0-23).

METHODS

Venous samples were taken on admission (t = 0) and at 24 h (t = 24). The serum samples were assayed for CK, CK-MB and cTnT on an Elecsys 1010 (Roche Diagnostics, Lewes, UK). The cTnT assay CV was 5.5% at 0.32 microg/l and 5.4% at 6.0 microg/l, and the detection limit was 0.01 microg/l with an upper limit of 25 microg/l. For cTnI using the Immulite (DPC, Gwynedd, Wales), the detection limit was 0.1 microg/l, and the upper limit was 180 microg/l. Final diagnostic categorization was performed by both WHO and European Society of Cardiology criteria using cTnT as the diagnostic cardiac biomarker. Patients were followed for the major adverse cardiac events (MACE), endpoints cardiac death, AMI or need for urgent revascularization. ROC curves were constructed using final diagnosis. Outcome prediction was assessed by ROC curves and Kaplan-Meier survival curves.

RESULTS

Both methods had equivalent diagnostic efficiency using WHO criteria for AMI. When ESC criteria were used the AUC for admission and 24 h cTnT and cTnI values were 0.945 vs. 0.910, P = 0.20 and 0.998 vs. 0.937, P = 0.005, respectively. Both methods predicted outcome as either death or MI or MACE and were not significantly different.

CONCLUSION

The Immulite cTnI assay can be used for diagnosis and risk stratification in patients admitted with non-ST segment elevation acute coronary syndromes.

The results of limb lengthening by callus distraction using an extending intramedullary nail (Fitbone) in non-traumatic disorders

Limb lengthening by callus distraction and external fixation has a high rate of complications. We describe our experience using an intramedullary nail (Fitbone) which contains a motorised and programmable sliding mechanism for limb lengthening and bone transport. Between 2001 and 2004 we lengthened 13 femora and 11 tibiae in ten patients (seven men and three women) with a mean age of 32 years (21 to 47) using this nail. The indications for operation were short stature in six patients and developmental or acquired disorders in the rest.

The mean lengthening achieved was 40 mm (27 to 60). The mean length of stay in hospital was seven days (5 to 9). The mean healing index was 35 days/cm (18.8 to 70.9). There were no cases of implant-related infection or malunion.

Anthropometric Measurements and Their Value in Predicting Complications Following Reduction Mammaplasty and Abdominoplasty

Body mass index (BMI) is the traditional way of assessing patients for body contouring surgery and has been shown to have a predictive value for surgical complications. In recent years, there have been discussions about accuracy of BMI as an indicator of obesity, and other obesity indices have been developed. This study aimed to measure and compare different anthropometric variables and examine their association with surgical morbidity. Prospective measurements of height, weight, waist, and percentage body fat were obtained preoperatively in 60 patients undergoing body contouring surgery. Demographics, patient characteristics, operative details, and postoperative complications were recorded. Statistical analysis was performed using chi, ANOVA, or Spearman rank correlations as appropriate. We found that BMI, percentage of body fat, weight, height-to-weight ratio, and waist circumference all correlate well as indicators of obesity and showed similar trends in their association with surgical complications.

A study on bed utilization in the gynaecological ward of a district hospital in West Bengal

A study was conducted in a non-paying gynaecological ward of the district hospital, South 24 Parganas, West Bengal to assess different bed efficiency indicators. Total 331 patients were admitted in 23 study beds (12 OPD beds and 11 emergency beds) during an observation period of six months. Overall average number of admissions were 14.4 and average length of stay 14.7days. Bed turnover rate was 13.8 and was higher for emergency beds (22.1) compared to OPD beds (9). Bed occupancy rate was 61.3% with significant difference between OPD beds (57.5%) and emergency beds (65.4%).

Use of bone wax to aid harvesting of chondrocutaneous composite grafts

For reconstruction of nasal defects, chondrocutaneous grafts harvested from ears are commonly used. Bone wax can be molded easily to create a three-dimensional form of the defect to be reconstructed. The mold then can be held against different parts of either ear to choose a site providing the best match of shape and size. The outline of the mold is drawn on the ear, and an appropriate chondrocutaneous graft can be easily harvested.

Is echocardiography a valid tool to screen for left ventricular systolic dysfunction in chronic survivors of acute myocardial infarction? A comparison with radionuclide ventriculography

OBJECTIVE

To assess the accuracy of echocardiography with Simpson's apical biplane method in screening for left ventricular systolic dysfunction (LVSD) in patients six months after acute myocardial infarction (AMI) as compared with radionuclide ventriculography by assessing the proportion of clinically significant errors that occur with echocardiography.

DESIGN

Comparison of results of echocardiography and radionuclide ventriculography in assessing left ventricular ejection fraction among patients six months after AMI.

SETTING

District general hospital.

PATIENTS

86 patients thrombolysed for AMI at six month follow up.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Correlation coefficients, mean differences, 95% limits of agreement, and differences of clinical significance between left ventricular ejection fraction on echocardiography and on radionuclide ventriculography.

RESULTS

The correlation coefficient between techniques was 0.90, mean difference 1% (p = 0.04), and 95% limits of agreement -13.0% to 10.3%. Only one patient (1.2%, 0.0% to 6.3%) was classified as having normal systolic function on one imaging modality but significant LVSD on the other. Overall accuracy between the two techniques was 86%, kappa value of agreement 0.78.

CONCLUSION

Echocardiography is a valid tool to screen for LVSD in patients six months after AMI, accurately differentiating normal from abnormal systolic function and showing excellent agreement with radionuclide ventriculography. This study supports the use of echocardiography in screening for LVSD in chronic stable patients after AMI or alternative high risk patients, with few differences of major clinical significance likely to occur.

Effects of carvedilol on left ventricular remodelling in chronic stable heart failure: a cardiovascular magnetic resonance study

BACKGROUND

The ability of beta blockers to improve left ventricular function has been demonstrated, but data on the effects on cardiac remodelling are limited.

OBJECTIVE

To investigate, using cardiovascular magnetic resonance (CMR), the effects of carvedilol on left ventricular remodelling in patients with chronic stable heart failure and left ventricular systolic dysfunction caused by coronary artery disease.

DESIGN

Randomised, double blind, placebo controlled study.

SETTING

Chronic stable heart failure.

PATIENTS AND INTERVENTION

34 patients with chronic stable heart failure and left ventricular systolic function taking part in the CHRISTMAS trial (double blind carvedilol v placebo) underwent CMR before randomisation and after six months of treatment.

MAIN OUTCOME MEASURE

Left ventricular remodelling at six months.

RESULTS

The carvedilol and placebo groups were well balanced at baseline, with no significant intergroup differences. Over the study period, there was a significant reduction in end systolic volume index (ESV(I)) and end diastolic volume index (EDV(I)) between the carvedilol and the placebo group (carvedilol -9 v placebo +3 ml/m2, p = 0.0004; carvedilol -8 v placebo 0 ml/m2, p = 0.05). The ejection fraction increased significantly between the groups (carvedilol +3% v placebo -2%, p = 0.003).

CONCLUSIONS

Treatment of chronic stable heart failure with carvedilol results in significant improvement in left ventricular volumes and function. These effects might contribute to the benefits of carvedilol on mortality and morbidity in patients with chronic heart failure.

Analytical performance of the N terminal pro B type natriuretic peptide (NT-proBNP) assay on the Elecsys™ 1010 and 2010 analysers

The Elecsys NT-proBNP assay is based on two polyclonal antibodies directed at residues 1-21 and 39-50 of the NT-proBNP molecule. Analytical performance was assessed using NCCLS protocol EP-5A using three serum pools in a preliminary study then as part of a multicentre evaluation (16 instruments in 8 hospitals). Using pools of 350 pg/l, 8700 pg/l and 13000 pg/l single site within run %CV was 0.7-1.6 (1010) and 1.2-1.5 (2010) and between run CV 5.3-6.7 (1010) and 4.4-5.0 (2010). In the multicentre evaluation within run CV was 1.0-2.5% with total imprecision 1.5-2.5% and between labs imprecision 3.8-4.0%. Functional sensitivity of <50 pg/l and measuring range to 35000 pg/l. There was excellent agreement between instrument platforms, y=0.97x+2.6; r=1.00 (n=215) for Elecsys 2010 (x) vs. Elecsys 1010 (y) and y=1.02x-0.3; r=1.00 (n=99) for Elecsys 2010 (x) vs. E 170 (y). Serum and heparin plasma samples showed good agreement but lower values were seen in EDTA plasma. Samples were stable for 7 days at room temperature; 21 days at 4 degrees C and for 5 freeze thaw cycles. Samples were obtained from a population of 1205 (671 male, 534 female) apparently healthy individuals screened by echocardiography and symptom questionnaire. There was poor correlation with NT-proANP (ELISA) (rs 0.33) and modest correlation with BNP (rs 0.89) with NT-proBNP values approximately 5 times greater than BNP (Biosite Triage). In a subset of 320 with normal ejection fraction (>50%) and no risk factors, NT-proBNP values increased with age and were higher in women than men.

Role of myocardial perfusion imaging for risk stratification in suspected or known coronary artery disease

Nuclear cardiology is an evolving specialty that has recently benefited from technological and radiopharmaceutical advances. As a result there has been an increase in the accuracy of myocardial perfusion imaging (MPI) with gated single photon emission computed tomography (SPECT) for assessing the diagnosis and prognosis of coronary artery disease. Moreover, ECG gated SPECT allows the simultaneous assessment of both myocardial perfusion and left ventricular function, which provides additional prognostic value. With increasing concern over early detection of coronary artery disease and its effective treatment, myocardial perfusion imaging is ideally placed to provide a full "one stop" functional assessment for any patient, irrespective of their exercise capacity. This applies not only to patients with chest pain but also to those with myocardial infarction, revascularisation, and heart failure, and those being assessed for non-cardiac surgery. The focus of this review is the use of myocardial perfusion imaging in risk stratification for coronary artery disease.

Myocardial perfusion imaging versus biochemical markers in acute coronary syndromes

The assessment and appropriate clinical management of patients with acute chest pain and non-diagnostic electrocardiograms remain a continuing clinical problem. Accordingly, there is considerable interest in evaluating new strategies to improve early diagnostic accuracy in patients with possible acute myocardial ischaemia. Cardiac troponins (T and I) and acute rest myocardial perfusion imaging have similar sensitivities for detecting acute myocardial infarction. Whereas cardiac markers require 6-12 h to become positive, acute rest myocardial perfusion imaging immediately reflects the status of regional myocardial blood flow at the time of radiopharmaceutical injection. The measurement of cardiac troponins is particularly useful in the diagnosis and estimation of the degree of myocardial injury in those patients with a high likelihood of coronary artery disease and myocardial necrosis and for prognostication of adverse cardiac events in those patients with unstable angina. In contrast, the most appropriate use of acute rest myocardial perfusion imaging is in the setting of patients with acute ischaemic symptoms, non-diagnostic electrocardiogram and a low likelihood of myocardial necrosis, in which early imaging will assist in effective triage decisions.

Myocardial viability as a determinant of the ejection fraction response to carvedilol in patients with heart failure (CHRISTMAS trial): randomised controlled trial

BACKGROUND

The improvement in left-ventricular ejection fraction (LVEF) in response to beta blockers is heterogeneous in patients with heart failure due to ischaemic heart disease, possibly indicating variations in the myocardial substrate underlying left-ventricular dysfunction. We investigated whether improvement in LVEF was associated with the volume of hibernating myocardium (viable myocardium with contractile failure).

METHODS

We did a double-blind, randomised trial to compare placebo and carvedilol for 6 months in individuals with stable, chronic heart failure due to ischaemic left-ventricular systolic dysfunction. We enrolled 489 patients, of whom 387 were randomised. Patients were designated hibernators or non-hibernators according to the volume of hibernating myocardium. The primary endpoint was change in LVEF, measured by radionuclide ventriculography, in hibernators versus non-hibernators, on carvedilol compared with placebo. Analysis was by intention to treat.

RESULTS

82 patients dropped out of the study because of adverse events, withdrawal of consent, or failure to complete the investigation. Thus, 305 (79%) were analysed. LVEF was unchanged with placebo (mean change -0.4 [SE 0.9] and -0.4 [0.8] for non-hibernators and hibernators, respectively) but increased with carvedilol (2.5 [0.9] and 3.2 [0.8], respectively; p<0.0001 compared with baseline). Mean placebo-subtracted change in LVEF was 3.2% (95% CI 1.8-4.7; p=0.0001) overall, and 2.9% (0.7-5.1; p=0.011) and 3.6% (1.7-5.4; p=0.0002) in non-hibernators and hibernators, respectively. Effect of hibernator status on response of LVEF to carvedilol was not significant (0.7 [-2.2 to 3.5]; p=0.644). However, patients with more myocardium affected by hibernation or by hibernation and ischaemia had a greater increase in LVEF on carvedilol (p=0.0002 and p=0.009, respectively).

INTERPRETATION

Some of the effect of carvedilol on LVEF might be mediated by improved function of hibernating or ischaemic myocardium, or both. Medical treatment might be an important adjunct or alternative to revascularisation for patients with hibernating myocardium.

Portable echocardiography: an innovative tool in screening for cardiac abnormalities in the community

AIMS

Heart failure is placing an increasing burden on society. This has led to calls for echocardiographic-based programmes to screen for left ventricular systolic dysfunction and other cardiac abnormalities. Echocardiography using new fully portable echocardiography devices would allow community-based cost-effective screening programmes once validated. This study was undertaken to evaluate this further in both high and low-risk subjects.

METHODS AND RESULTS

562 consecutive subjects attending a community-based heart failure screening programme, some at high-risk and some at low-risk of cardiac abnormalities, underwent echocardiography by both portable and traditional echocardiography machines. An 'eyeball' estimate of left ventricular ejection fraction was made on the portable device and compared to a quantitative measure of ejection fraction on the traditional machine. Qualitative measures of valvular regurgitation and quantitative measures of left ventricular hypertrophy were also compared. An estimate of ejection fraction was possible in 97% of cases using portable echocardiography. It gave a sensitivity, specificity and negative predictive value in diagnosing left ventricular systolic dysfunction of 96%, 98% and 99.6%, respectively. Inter-observer variability gave a mean difference in ejection fraction of 2%, and 95% limits of agreement of -8% to +12%. All cases of moderate or severe valvular regurgitation and 29 of 31 cases of significant left ventricular hypertrophy were correctly identified as abnormal on the portable device.

CONCLUSIONS

Thus, echocardiography performed by experienced sonographers using these new fully portable devices is an accurate and reproducible technique for detecting left ventricular systolic dysfunction, left ventricular hypertrophy and valvular regurgitation in both high-risk and low-risk members of the community. Its very high negative predictive values would allow their use in future community-based screening programmes.