Malfunction of Subpectorally Implanted Cardiac Resynchronization Therapy Defibrillators Due to Weakened Header Bond

Malfunction of Subpectorally Implanted Cardiac Resynchronization Therapy . Background: Implantable cardioverter defibrillator (ICD) implantation has increased significantly over the last 10 years. Concerns about the safety and reliability of ICD systems have been raised, with premature lead failure and battery malfunctions accounting for the majority of reported adverse events. We describe the unique mode of presentation, diagnosis, and management of cardiac resynchronization therapy defibrillators (CRT‐D) malfunctions that were caused by weakened bonding between the generator and header. Methods and Results: Between June 2008 and December 2009, 22 Teligen? ICDs and 24 Cognis? CRT‐Ds were implanted subpectorally at our institution, until a product advisory was issued. Of 24 Cognis? CRT‐D implants, 3 patients presented with CRT‐D malfunctions. All our cases presented with initially intermittent and then persisting increases in shock lead impedance, associated with nonphysiological noise in the shock electrogram channels. These issues were rectified by generator change. Postexplant laboratory analysis confirmed inadequate bonding between device header and titanium casing in all cases, resulting in loosening and rocking of the header followed by fatigue‐induced fracture of the shock circuitry. Conclusion: Weakened bonding between the header and generator casing of subpectorally implanted CRT‐Ds can result in fractures and malfunction of the HV circuit. Physicians monitoring patients with devices affected by the product advisory should remain vigilant in order to diagnose and manage similar device malfunction expediently. (J Cardiovasc Electrophysiol, Vol. 24, pp. 351‐355, March 2013)     

SERUM BIOCHEMISTRY IN RHEUMATOID ARTHRITIS, SERONEGATIVE ARTHROPATHIES, OSTEOARTHRITIS, SLE AND NORMAL SUBJECTS

Most arthritic conditions are characterized by chronic inflammation,resulting in secondary changes in serum biochemistry. In anattempt to profile different mechanisms of inflammation whichmight account for the clinical diversity of rheumatic diseases,we have measured C-reactive protein (CRP), plasma viscosity,serum histidine and total serum sulphydryl in 259 patients withrheumatoid arthritis (RA), 84 with ankylosing spondylitis (AS),76 with osteoarthritis, 69 with psoriatic arthritis, 34 withsystemic lupus erythematosus (SLE), 36 with Reiter's syndromeand 121 normal controls. The most extreme abnormalities were seen in rheumatoid arthritisand the least in osteoarthritis. The seronegative spondarthritidesand SLE occupied a midway position, emphasizing a correlationbetween biochemical abnormality and severity of inflammation. A low serum histidine characterized both RA and SLE. The formerwas more likely to be associated with a raised CRP. Plasma viscositywas characteristically raised in psoriatic arthritis and CRPin AS. KEY WORDS: Serum biochemistry, Rheumatoid arthritis, Seronegative arthropathies     

OSTEOARTHRITIS IN WEIGHT-BEARING WRISTS?

To test the suggestion [1] that turning the wrist into a weight-bearingjoint by using a stick is likely to cause OA in that joint,50 consecutive patients (excluding those with RA) who had useda stick for more than 1 year were studied clinically and radiographically.The data did not support this hypothesis. The changes in theoriginal paper, as in one of these patients. were likely tobe due to avascular necrosis.     

SULPHASALAZINE ALONE OR IN COMBINATION WITH D-PENICILLAMINE IN RHEUMATOID ARTHRITIS

Thirty patients (22 women) with active rheumatoid arthritisparticipated in an open study of 6 months' treatment with eitherenteric-coated sulphasalazine (SASP) or SASP plus D-penicillamine(DPA). Patients were assessed at regular intervals using a numberof clinical and biochemical tests designed to detect specificantirheumatic activity. There were significant improvements in clinical and laboratoryvariables with both regimens consistent with second-line activity.Improvements were greater and more numerous with combinationtherapy. At the end of the trial period, there were nine ‘responders’in the SASP/DPA group but only six in the SASP group. Neitherefficacy nor toxicity could be related to patient acetylatorstatus. Nausea and dyspepsia were frequent problems with both treatmentregimens but dysgeusia and thrombocytopenia were confined tothe SASP/DPA group. Study withdrawals were twice as common withcombination therapy. These results suggest that a combination of SASP and DPA ismore potent than SASP alone but at the expense of poorer patienttolerance. KEY WORDS: Rheumatoid arthritis, Sulphasalazine, D-Penicillamine, Combination therapy     

Automatic recording and timing of defibrillation on general wards by day and night

To measure the speed of response to ventricular fibrillationon general medical wards and to assess the importance of thisand other factors for survival to leave hospital, 69 consecutivepatients with ventricular fibrillation were studied prospectivelyusing an automatic timing device in the hospital telephone exchangeand an automatic timer and ECG recording during resuscitation. Twenty-seven patients were initially resuscitated and 17 weredischarged from hospital. The median time to connect the monitorafter recognition of a cardiac arrest was 127 s (range 0–277)for survivors and 132.5 s (range 0–620) for non-survivors.The median time ventricular fibrillation was displayed beforethe first shock was 43 s (range 4–75) for survivors and52 s (range 10–454) for non-survivors. These differenceswere not significant; but logistic regression analysis identifiedprimary ventricular fibrillation, short display time (loggeddata), ‘early’ time of day, absence of pre-existingnon-cardiac illness, and post-defibrillation heart-rate >30beats. min^–1 in rank order as independent predictors ofsurvival. In spite of no significant diurnal variation in responsetime, successful resuscitations were concentrated in the earlynursing shift (0730–1530 h). Four shocks were inappropriate. Clinical diagnosis was more predictive of outcome than the timeto the first shock. The reasons for the poorer results in theevening and night are uncertain.Ventricular fibrillation, defibrillation,cardiac arrest, ambulatory ECG recording, resuscitation training.     

Identification and characterization of human B-cell epitopes in recombinant antigens of Leishmania aethiopica

Recombinant DNA fragments from Leishmania aethiopica that code for epitopes which react with human antibodies have been characterized by cross-hybridization studies and DNA sequence analysis. Twenty clones could be grouped into seven different groups (I–VII), probably representing seven different L. aethiopica antigens. The DNA sequences of representative clones from the seven groups have been obtained and the amino acid sequence of the respective recombinant antigens established. The recombinant antigens have been analysed by epitope scanning with patient sera, and octapeptides that contain potential B-cell epitopes have been identified in all seven recombinant antigens. These octapeptides have further been tested with additional patient sera and control sera, and three octapeptides (HAFCHEEG, YHSSVVHD and SYAPCSLK) were found to contain major epitopes recognizing specific antibodies in nine, seven and four, respectively, of the twenty sera tested. Fifteen of the twenty sera reacted with one or more of these three octapeptides.     

ARTHRITIS AND INTESTINAL DISEASES: A COMPARISON OF TWO FAMILY STUDIES

A comparison has been made between the results of two familystudies. Ninety-one patients with ulcerative colitis, 116 patientswith Crohn's disease and 449 of their relatives and spouseswere examined clinically and radiologically. A further 96 relativesand spouses were reviewed radiologically only. Intestinal synovitiswas found more frequently in patients with Crohn's disease thanin those with ulcerative colitis. This result was in accordwith published evidence and theoretical considerations. Sacro-iliitiswas found in similar proportions of probands, first-degree relatives,second-degree relatives, and spouses in each study. More ofthe subjects in the ulcerative colitis study were diagnosedas having ankylosing spondylitis, while a greater proportionof subjects with sacro-illtis in the Crohn's disease study werefemale. The possible interrelationship between these facts hasbeen discussed. ^*Formerly William Hewitt Research Fellow: Honorary Senior Registarin Rheumatology, Now Consultant Rheumatologist, South TeessideHospital Group Formerly Research Fellow Professor of Rheumatology     

Detection of ambulatory ischaemia is not of practical clinical value in the routine management of patients with stable angina: A long-term follow-up study

It has been reported that medically treated patients with stableangina and positive exercise test for ischaemia have an adverse1–2 year outlook if they are shown also to have transient,and predominantly silent, ischaemic episodes detected by ambulatoryST segment monitoring during their daily activities: it hasbeen suggested that this investigation could be used to identifypatients more likely to benefit from early investigation andtreatment. We assessed the long-term (up to 65 months) prognosticsignificance of transient iscliaemic episodes during daily activitiesin 172 patients routinely attending cardiac outpatients withmedically treated stable angina who had undergone exercise testingand 48 h of ambulatory ST segment monitoring between February1988 and August 1989 for this purpose. A positive exercise testfor ischaemia was not a prerequisite for inclusion. One hundred and four patients (60.5%) had a positive exercisetest for iscliaemia and 72 (42%) had transient ischaemia duringdaily activities (63 had both tests positive). Over a median50-month follow-up period 54 patients suffered at least onecardiac event (primary event: cardiac death n=7; non-fatal myocardialinfarction n=11; unstable angina n=18; elective CABGIPTCA n=18).Two further patients suffered non-cardiac death. Cardiac events,either objective (cardiac death or non-fatal myocardial infarction)or subjective (unstable angina or revascularisation) were nomore likely to occur in those with transient ischaemia duringdaily life when compared with those without, at follow-up timesup to 65 months. The detection of transient ischaemia during daily life is oflimited practical clinical value in the management of ‘lowrisk’ medically treated patients with stable angina, anddoes not appear to help identify subgroups at increased riskof an adverse outcome at follow-up to more than 5 years.