Red Cell Lead and δ-Amino Levulinic Acid Dehydratase

Objective: The present study focusses on serum testosterone concentrations in patients with skeletal fluorosis, in order to assess the hormonal status in fluoride toxicity. Methods: Serum testosterones were compared for patients afflicted with skeletal fluorosis (n = 30) and healthy males consuming water containing less than 1 ppm fluoride (Control 1, n = 26) and a second category of controls (Control 2, n = 16): individuals living in the same house as the patients and consuming same water as patients but not exhibiting clinical manifestations of skeletal fluorosis. Results: Circulating serum testosterones in skeletal fluorosis patients were significantly lower than those of Control 1 atp <0.01. Testosterone concentrations of Control 2 were also lower than those of Control 1 at p <0.05 but were higher than those of the patient group. Conclusion: Decreased testosterone concentrations in skeletal fluorosis patients and in males drinking the same water as the patients but with no clinical manifestations of the disease compared with those of normal, healthy males living in areas nonendemic for fluorosis suggest that fluoride toxicity may cause adverse effects on the reproductive system of males living in fluorosis endemic areas.     

Laser Lead Extraction: Is There a Learning Curve?

Laser extraction of device leads offers an attractive alternative to countertraction and electrosurgical dissection sheath, potentially increasing efficacy and reducing complications. Wider adoption of this technology depends on relative ease of use. We report the experience of a new center to define the "learning curve." We performed 76 laser lead extractions in 75 patients (age 63 +/- 17 years, 59 male) from July 2001 to January 2004. Two experienced device implanters who were novice extractors underwent a 2-day site visit to a high volume extraction center for training. Lead extractions were performed in the operating room with immediate surgical backup. The indication for extraction was infection in 39 (systemic in 15), erosion or pain in 11, and lead related or debulking in 25. Complete removal was achieved in 139 of 145 leads (14 ICD, 131 pacemaker). Partial removal (<4 cm retained) was achieved in five leads (4%), and one lead could not be extracted. Complete success was 95% in the first third of patients, 94% in the second third, and 100% in the latter third. Fluoroscopy time fell from 19 +/- 22 minute in the first third of patients to 11 +/- 8 minute in the second third to 8 +/- 4 minute in the latter third (ANOVA P = 0.02). No major complications occurred. Local bleeding required minor left subclavian vein repair in two individuals. Symptomatic venous thrombosis occurred in 3 of the first 11 cases 1-21 days after extraction, but did not occur in the next 64 consecutive patients who received a 1-month anticoagulation regimen (27% vs 0%, P < 0.001). One patient developed venous thrombosis 3 weeks following cessation of warfarin therapy. Practice guidelines reasonably recommend appropriate training prior to independent performance of lead extraction. The current study suggests that experienced device implanters with appropriate operative backup taking a limited, but intensive training program can be safe and effective at lead extraction in a short time, in part a reflection of the improved technology.     

Does Disseminated Intravascular Coagulation Lead to Multiple Organ Failure?

Microvascular dysfunction with its associated impaired regional oxygen transport and use is believed to be the final common pathway in the development of multiple organ failure. The precise mechanisms underlying this dysfunction, however, are uncertain. Activation of the coagulation system is a key feature in the pathogenesis of sepsis, but whether it is also the cause of multiple organ failure is unclear. This article discusses the evidence for and against a key role for disseminated intravascular coagulation in the pathogenesis of multiple organ failure.     

The Neglected Lead on Electrocardiogram: T Wave Inversion in Lead aVL,Nonspecific Finding or a Sign for Left Anterior Descending Artery Lesion?

Background

The electrocardiogram (ECG) is the most important diagnostic tool for acute myocardial infarction (AMI). T wave inversion (TWI) in lead aVL has not been emphasized or well recognized.

Objective

This study examined the relationship between the presence of TWI before the event and mid-segment left anterior descending (MLAD) artery lesion in patients with AMI.

Methods

Retrospective charts of patients with acute coronary syndrome between the months of January 2009 and December 2011 were reviewed. All patients with MLAD lesion were identified and their ECG reviewed for TWI in lead aVL.

Results

Coronary angiography was done on 431 patients. Of these, 125 (29%) had an MLAD lesion. One hundred and six patients (84.8%) had a lesion > 50% and 19 patients (15.2%) had a lesion < 50%. Of the 106 patients who had a MLAD lesion > 50%, 90 patients (84.9%) had TWI in lead aVL and one additional lead. Of the 19 patients who had an MLAD lesion < 50%, 8 patients (42.1%) had TWI in lead aVL and one additional lead. Isolated TWI in lead aVL had an overall sensitivity of 76.7% (95% confidence interval [CI] 0.65–0.86), a specificity of 71.4% (95% CI 0.45–0.88), a positive predictive value of 92%, a negative predictive value of 41.7%, a positive likelihood ratio of 2.7 (95% CI 1.16–6.22), and negative likelihood ratio of 0.32 (95% CI 0.19–0.58) for predicting a MLAD lesion of > 50% (p = 0.0011).

Conclusions

TWI in lead aVL might signify a mid-segment LAD lesion. Recognition of this finding and early appropriate referral to a cardiologist might be beneficial. Additional studies are needed to validate this finding.     

Rise in ICD Shock Impedance: Lead Fracture or Death?

Background: Remote monitoring allows for interrogation and extensive data retrieval of implantable cardioverter-defibrillators (ICDs). Data on ICD parameters at the time of death and afterwards are limited. The purpose of this retrospective study was to examine the changes in lead impedances of ICDs at the time of death and afterwards. Methods: A total of 37 Biotronik (SE & CO. KG, Berlin, Germany) ICDs (20 ICD-cardiac resynchronization therapy, 16 dual-chamber ICDs, and one single-chamber ICD), retrieved after death, were interrogated. Stored intracardiac electrograms were analyzed to determine the cause of death. Impedance trend curves of shock and pacing lead impedances were analyzed and correlated retrospectively with the reported time of death. The influence of cold exposure on lead impedances was tested in three other single-chamber Biotronik ICDs. Results: Of 37 patients, the cause of death was due to ventricular tachyarrhythmias in 21 patients. In 12 patients, death was not arrhythmia-related. In four patients, the cause of death could not be determined due to overwriting of the episodes at the time of death. A significant increase of shock and pacing lead impedances was observed in the postmortem days (P < 0.001 for all lead impedances). All lead impedance values increased significantly within the first postmortem day (P < 0.001 for all lead impedances). Cold exposure decreased shock lead impedance but did not affect pacing lead impedance. Conclusion: Postmortem analysis of ICDs allows tracking of lead impedance changes, which correlate with the day of death. The rise in postmortem impedances should not be interpreted as contributing to the mode of death. (PACE 2012; 35:1103-1110).     

Lead‐Contaminated Drinking Waters in the Public Schools of Philadelphia

Lead exposure is a preventable environmental health concern. Young children between the ages of 1 to 6 are most susceptible to its clinical effects. This article reports the results of lead level determinations in the drinking water of Philadelphia's public school buildings and remediation efforts aimed at dealing with this public health concern. Methods: Water samples were collected from drinking sources in 292 school buildings in Philadelphia from May 2000 through January 2001. These samples were collected and sent to reference laboratories for determination of lead levels. Results: A total of 42.5% (124) of schools had water lead levels not exceeding the action level of 20 ppb, of which 3.1% had nondetectable levels or levels less than 5 ppb. A total of 28.7% of buildings had water lead levels ranging from 20 to 50 ppb, 11.6% had levels between 50–100 ppb, and 17.1% had water lead levels of 100 ppb or more. Conclusion: A total of 57.4% of Philadelphia's public school buildings had water lead levels exceeding the Environmental Protection Agencies (EPA) action level of 20 ppb, and 28.7% of school buildings had water with mean lead levels in excess of 50 ppb. Depending on the volume of water consumed, drinking water from school buildings may be a significant source of lead exposure for children in their formative years of development. Although Philadelphia's public school buildings were evaluated, lead‐contaminated drinking water in schools is not only an urban concern. School buildings in suburban and rural areas may have similar water lead levels, and testing programs are desirable.     

Atrial Lead Placement During Atrial Fibrillation. Is Restitution of Sinus Rhythm Required for Proper Lead Function? Feasibility and 12‐Month Functional Analysis

Unexpected atrial fibrillation (AF) during implantation of an atrial pacemaker lead is sometimes encountered. Intraoperative cardioversion may lengthen and complicate the implantation process. This study prospectively investigates the performance of atrial leads implanted during AF (group A) and compares atrial sensing and pacing properties to an age- and sex-matched control group in which sinus rhythm had been restored before atrial lead placement (group B). Patient groups consisted of 32 patients each. All patients received DDDR pacemakers and bipolar, steroid-eluting, active fixation atrial leads. In patients with AF at the time of implantation (group A), a minimal intracardiac fibrillatory amplitude of at least 1.0 mV was required for acceptable atrial lead placement. In patients with restored sinus rhythm (group B), a voltage threshold < 1.5 V at 0.5 ms and a minimal atrial potential amplitude > 1.5 mV was required. Patients of group A in whom spontaneous conversion to sinus rhythm did not occur within 4 weeks after implantation underwent electrical cardioversion to sinus rhythm. Pacemaker interrogations were performed 3, 6, and 12 months after implantation. In group A, implantation time was significantly shorter as compared to group B (58.7 +/- 8.6 minutes vs 73.0 +/- 17.3 minutes, P < 0.001). Mean atrial potential amplitude during AF was correlated with the telemetered atrial potential during sinus rhythm (r = 0.49, P < 0.001), but not with the atrial stimulation threshold. Twelve months after implantation, sensing thresholds (1.74 +/- 0.52 mV vs 1.78 +/- 0.69 mV, P = 0.98) and stimulation thresholds (1.09 +/- 0.42 V vs 1.01 +/- 0.31 V, P = 0.66) did not differ between groups A and B. However, in three patients of group A, chronic atrial sensing threshold was < or = 1 mV requiring atrial sensitivities of at least 0.35 mV to achieve reliable atrial sensing. Atrial lead placement during AF is feasible and reduces implantation time. However, bipolar atrial leads and the option to program high atrial sensitivities are required.     

The Lead Cancer Nurse – an ill‐defined role?

The Lead Cancer Nurse (LCN) role was developed following the publication of the NHS Cancer Plan [Department of Health (2000) The NHS Cancer Plan. A Plan for Investment. A Plan for Reform. HMSO, London]. In collaboration with the Lead Cancer Clinician and Cancer Manager the role of the LCN is to contribute to the planning and delivery of cancer services in line with government guidance. However, there are significant variations in the remit and authority of the role between organizations, and limited research has been undertaken to evaluate the effectiveness of this senior nursing post. This article explores the complex and often ill-defined remit of the LCN role and compares this with Nurse Consultant and Advanced Nurse Practitioner roles. It explores the challenges that this presents both to the postholders and the organizations within which they work. Recommendations include on-going monitoring and evaluation of these posts, the development of local supportive frameworks and a review of the educational needs of these postholders.     

Resynchronization: What if the Left Ventricular Lead Cannot Reach the Lateral or Posterolateral Wall?

Background: The recommended left ventricular (LV) lead position for cardiac resynchronization therapy (CRT) is at the lateral or posterolateral wall. However, LV leads cannot always be implanted at this site. The objective of our study was to compare the clinical response to CRT when the LV lead could be implanted or not at the lateral or posterolateral wall.
Methods: In consecutive patients implanted with a CRT device, we documented the final position achieved by the tip of the LV lead in the left anterior oblique projection. Patients were prospectively followed for 6 months after implantation. They were defined as responders if they were alive, had gained 1 New York Heart Association (NYHA) functional class, and had not been hospitalized for heart failure.
Results: The study population consisted of 77 patients (56 men, 71 ± 10 years, 62 NYHA class III, 15 NYHA class IV). The LV lead was implanted at the lateral or posterolateral wall in 54 patients (group A) and at the anterior or anterolateral wall in 23 patients (group B). At 6 months, seven patients (9%) died (all in group A). There were 37 responders (69%) in group A as compared to 22 (96%) in group B.
Conclusions: The responder rate was not inferior when the LV lead was implanted at the anterior or anterolateral wall. Thus, in case of failed implantation at the lateral or posterolateral wall, positioning the LV lead in a more anterior location appears to be a reasonable alternative. Further studies are required to confirm these findings.     

Lead aVL on electrocardiogram: emerging as important lead in early diagnosis of myocardial infarction?

Although a diagnosis of acute myocardial infarction (AMI) that mandates emergency reperfusion therapy requires ST-segment elevation greater than 1 mm in at least 2 contiguous leads, some of the early electrocardiogram (ECG) changes of AMI can be subtle. Any ST-segment depression or T-wave inversion in lead aVL may be implicated in left anterior descending artery lesion or early reciprocal changes of inferior wall myocardial infarction, particularly when the clinical context suggests ischemia. Early recognition of reciprocal changes and serial ECG help initiate early appropriate intervention. Heightened awareness of ST segment and T-wave changes in lead aVL is of paramount importance to quickly identifying life-threatening condition.     

Are Antimony-Bismuth Aprons as Efficient as Lead Rubber Aprons in Providing Shielding against Scattered Radiation?

AimThe aim of this study is to compare the absorption ability of two lead-free aprons with a lead apron.MethodThe absorption ability of three aprons was measured and compared; Opaque Fusion 0.35 mm (OpaqFu) bilayer apron containing bismuth and antimony, No Lead 0.35 mm (NoLead) one-layer apron containing antimony, and a lead apron. The measurements were repeated with and without each of the aprons present in both primary and scattered beams. The selected tube voltages were between 60 and 113 kVp with constant mAs, a fixed field size, and fixed source-to-object distance.ResultsNo significant difference in absorption ability of the two lead-free aprons compared with that of the lead apron was observed when the dose was measured in the primary beam. When measurements were performed in the scatter radiation field, the absorption ability of the OpaqFu apron was 1.3 times higher than that of NoLead apron and nearly equal to the absorption ability of the lead apron. An increase in the difference between the OpaqFu and NoLead aprons was observed for the tube energies higher than 100 kVp in favour of OpaqFu apron.ConclusionIt is safe to use the lead-free aprons that were tested in this study in a clinical environment for the tube energy range of 60 kVp–113 kVp.     

Impedance Changes on Defibrillation Coils after Atrial Fibrillation Ablation: Lead Damage or Electromechanical Interference?

Fluctuation of impedance on defibrillator leads is highly suggestive of lead failure. A drop in impedance is associated with insulation defects while high impedance is suggestive of lead fracture. In this case report, we described a patient where electromagnetic interference from radiofrequency ablation near the site of superior vena cava coil caused the sensed impedance to fluctuate without uneventful outcomes and we discussed the possible mechanism. Both electromagnetic interference and defibrillator lead insulation defect can result in low threshold and inappropriate shocks. Sometimes electromagnetic interference may result in physical damage of the implanted system and may result in subsequent fluctuations in impedance. Awareness of electromagnetic interference that can cause fluctuating impedance without structural damage can help in making appropriate diagnosis and may avoid unnecessary procedures.     

Late Right Ventricular Perforation After Permanent Pacemaker Implantation: How Far Can the Lead Go?

This case report describes the incredible dislocation of a right ventricular lead 1 month after pacemaker implantation. The lead's tip was found in the subcutaneous fat beneath the left breast. Extraction was uneventful. The key steps in the diagnosis and management of this rare complication are discussed.     

Tricuspid Endocarditis in an Adult Patient with Ebstein’s Anomaly who has a Residual Pacemaker Lead

Ebstein’s anomaly is defined as an apical displacement of the attachment of the septal tricuspid valve leaflet from the right atrioventricular annulus that exceeded 1.2 cm in length. Patients with Ebstein’s anomaly are known to have a high potential for developing arrhythmia, in the vast majority, of the tachycardia type. Infective endocarditis is characterized by ulcerovegetational lesions that result from the graft of a microorganism, usually bacterial, on the valvuler endocardium (native valve endocarditis) or on a prosthesis (prosthetic valve endocarditis). Ebstein’s anomaly with tricuspid regurgitation is also thought to be a predisposing condition for infective endocarditis. In this case, we report a patient who presented with atrial flutter and infective endocarditis due to residual pacemaker lead and Ebstein’s anomaly.