Complete heart block in an adult with systemic lupus erythematosus and recent onset of hydroxychloroquine therapy

Hydroxychloroquine and the associated risk of arrhythmias

Hydroxychloroquine (HCQ), which was initially used as an antimalarial drug, is now being used to treat other illnesses, especially rheumatic autoimmune disorders  such as systemic lupus erythematosus, primary Sjögren's syndrome, and rheumatoid arthritis, because it is safe, effective, and cost efficient. This drug has shown high efficacy and has become the first-line treatment for many of these diseases. Although HCQ has many therapeutic effects, it has unfortunately shown some complications, especially with its long-term use. One of these side effects is arrhythmia through prolongation of the QT interval. This narrative literature review focuses on the effects of HCQ on the QT interval in patients with rheumatologic diseases who have been prescribed this drug. In particular, we will focus on the increased risk of arrhythmia when HCQ is administered with other drugs, such as azithromycin and many others, along with drug-drug interactions. In addition, we investigated the safety of this drug in pregnant women.

Safety of Short-Term Treatments with Oral Chloroquine and Hydroxychloroquine in Patients with and without COVID-19: A Systematic Review

Chloroquine (CQ) and hydroxychloroquine (HCQ) have recently become the focus of global attention as possible treatments for Coronavirus Disease 2019 (COVID-19). The current systematic review aims to assess their safety in short treatments (≤14 days), whether used alone or in combination with other drugs. Following the PRISMA and SWiM recommendations, a search was conducted using four health databases for all relevant English-, Chinese-, and Spanish-language studies from inception through 30 July 2021. Patients treated for any condition and with any comparator were included. The outcomes of interest were early drug adverse effects and their frequency. A total of 254 articles met the inclusion criteria, including case and case-control reports as well as cross-sectional, cohort, and randomised studies. The results were summarised either qualitatively in table or narrative form or, when possible (99 studies), quantitatively in terms of adverse event frequencies. Quality evaluation was conducted using the CARE, STROBE, and JADAD tools. This systematic review showed that safety depended on drug indication. In COVID-19 patients, cardiac adverse effects, such as corrected QT interval prolongation, were relatively frequent (0–27.3% and up to 33% if combined with azithromycin), though the risk of torsade de pointes was low. Compared to non-COVID-19 patients, COVID-19 patients experienced a higher frequency of cardiac adverse effects regardless of the regimen used. Dermatological adverse effects affected 0–10% of patients with autoimmune diseases and COVID-19. A broad spectrum of neuropsychiatric adverse effects affected patients treated with CQ for malaria with variable frequencies and some cases were reported in COVID-19 patients. Gastrointestinal adverse effects occurred regardless of drug indication affecting 0–50% of patients. In conclusion, CQ and HCQ are two safe drugs widely used in the treatment of malaria and autoimmune diseases. However, recent findings on their cardiac and neuropsychiatric adverse effects should be considered if these drugs were to be proposed as antivirals again.

Hydroxychloroquine use is not associated with QTc length in a large cohort of SLE and RA patients

Background

Hydroxychloroquine (HCQ) is a cornerstone therapy for systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). However, reports of its use and subsequent fatal arrhythmias in patients with coronavirus disease 19 (COVID-19) have raised concern regarding its cardiovascular (CV) safety. Therefore, we examined the relationship between HCQ use and corrected QT (QTc) length in SLE and RA patients without clinical CV disease (CVD).

Methods

SLE patients from the Columbia University Lupus Cohort registry (n = 352) and two RA cohorts (n = 178; ESCAPE-RA and RHYTHM-RA) with electrocardiograms (ECGs) collected as part of study data were analyzed. RA cohort participants were recruited from tertiary referral centers with additional referrals from community rheumatologists, while SLE subjects originated from the Columbia University Lupus Cohort. All patients met American College of Rheumatology (ACR) classification criteria for SLE or RA and lacked known CVD. The exposure of interest was HCQ use and main outcome measure was QTc length [continuous or categorical (≥ 440 ms and ≥ 500 ms)].

Results

Of the combined SLE and RA cohorts (n = 530), 70% were HCQ users and 44% had a QTc ≥ 440 ms. The adjusted mean QTc length was comparable between HCQ users vs non-users (438 ms vs 437 ms). In multivariable logistic models, HCQ use was not a significant predictor of a QTc ≥ 440 ms for the entire cohort (OR 0.77; 95% CI 0.48–1.23; p = 0.27). Importantly, a QTc ≥ 500 ms was inversely associated with HCQ use and not associated with arrhythmias or deaths. A significant interaction was found between HCQ use and use of anti-psychotics. Ultimately, the use of HCQ combined with any QTc prolonging medication as a group was associated with a QTc length (434 ms; 95% CI 430, 439) which was comparable to that of use of HCQ alone (433 ms; 95% CI 429-437).

Conclusion

In a combined cohort of SLE and RA patients without clinical CVD, adjusted QTc length was comparable between HCQ and non-HCQ users, supporting its CV safety in patients with rheumatic diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02646-0.

Systemic immune-inflammation index as a tool for predicting the need for a permanent pacemaker in patients with drug-induced atrioventricular block

BACKGROUND

Drug-induced atrioventricular block (AVB) is generally considered reversible and does not require a permanent pacemaker implantation (PPM). However, some studies have demonstrated a failure of AVB cessation even when the inducing agent has been discontinued. This study has investigated the use of systemic immune-inflammation index (SII) to predict irreversible drug-induced AVB after drug discontinuation.

METHOD

Files of patients with high-degree AVB that required a temporary pacemaker (TPM) were retrospectively analyzed. Sixty-three patients in which AVB was drug-induced were included in the study. The patients were divided into the following two groups: (1) those whose AVB reversed after discontinuation of the related drug, and (2) those in which AVB did not reverse.

RESULTS

AVB reversed in 24 patients (38%) after the inducing agent was discontinued while in the remaining 39 patients (62%) PPM was required. The most common drugs to induce AVB were beta-blockers (n = 46, 73%). Follow-up time with TPM was significantly longer in the irreversible group (2.91 ± 1.05 days vs. 4.94 ± 2.15 days, p < .001). Multivariate logistic regression analysis showed that SII (odds ratio [OR] = 1.002; 95% confidence interval [CI] = 1.000-1.003; p = .01) was an independent predictor of the requirement for a PPM. An SII > 752.05 was found to be a predictor of irreversible AVB requiring PPM with a sensitivity of 64% and specificity of 75% (receiving-operating characteristics [ROC] area under the ROC curve [AUC]: 0.704, 95% CI = 0.570-0.838, p = .007).

CONCLUSION

Approximately 2/3 of drug-induced high-degree AVBs are irreversible. SII is an easily available and cheap inflammatory biomarker that can be used to predict irreversible AVB.

Usefulness of cardiac screening in patients with systemic lupus erythematosus and anti-Ro/SSA antibodies

OBJECTIVES

Recent data suggest that some adult patients with autoimmune rheumatic diseases may develop cardiac conduction and repolarization abnormalities mediated by anti-Ro/SSA antibodies. We aim to investigate the utility of a cardiac screening in patients with systemic lupus erythematous (SLE) and anti-Ro/SSA positivity.

METHODS

SLE patients who consecutively attended a Rheumatology clinic during 1 year where evaluated for the presence and levels of anti-Ro/SSA antibodies, and clinical and biological markers of organ damage and disease activity. All participants underwent a cardiovascular anamnesis and physical examination, ECG, echocardiography, and 24-hour Holter.

RESULTS

Of the 145 recruited patients, 49 (32%) had anti-Ro/SSA positivity. None had any degree of atrioventricular block in the ECG or Holter monitoring. No significant differences were observed between anti-Ro/SSA-positive vs. negative patients in terms of PR, QRS or QTc intervals. No clinically significant arrhythmias were recorded during Holter monitoring and no differences in average heart rate, heart rate variability, or atrial or ventricular ectopy burden were observed. Finally, no differences were found in echocardiographic measurements.

CONCLUSIONS

In this study of SLE patients, anti-Ro/SSA positivity was not associated with significant alterations in ECG, echocardiography, or 24-hour Holter. These findings do not support ordinary cardiac evaluation in these patients. (Clinicaltrials.gov registration number: NCT02162992).

Suspected Hydroxychloroquine-Induced Sinus Bradycardia and QTc Prolongation in a Patient with COVID-19

An 84-year-old woman with hypertension, Alzheimer's disease, and chronic kidney disease presented with fever and was diagnosed with corona virus disease 2019 (COVID-19). During the hospitalization, she experienced unexpected sinus bradycardia with prolonged QTc, which was thought to be closely related to the short-term use of hydroxychloroquine (HCQ), an old drug used to treat malaria and autoimmune diseases, but now used against COVID-19. The cardiac side effects of HCQ were rare, seen with short-term and low-dose use. With the COVID-19 pandemic, this case alerts clinicians to be aware of the arrhythmogenic effects of HCQ when it is used as an antiviral drug, especially in patients with preexisting cardiovascular diseases.

Complete heart block in lupus

Conduction abnormalities are uncommon in adult patients with lupus. We present a young woman with recurrent syncope caused by third-degree atrio-ventricular block as the initial manifestation of lupus and review 31 additional cases of systemic lupus erythematosus patients that have been described previously with complete heart block. Heart blocks occurred almost exclusively in females. The median age was 37 years. In 24 cases heart blocks were diagnosed in patients with established lupus. In only five patients, including the patient presented here, heart blocks were diagnosed before the lupus diagnosis. Syncope was the most common presenting symptom of heart block. Electrocardiographic findings prior to heart block episodes were reported in 17 cases: eight had normal findings, but nine had already variant forms of atrioventricular or intraventricular conduction defects. Anti-nuclear antibody tests were reported in 25 cases and were all positive. Anti-DNA antibodies were also common and were positive in 16 of 19 cases (84%). Anti-La and anti-Ro antibodies were less common (13% and 35%, respectively). Three patients died, all prior to 1975. Heart block resolved in 10 cases. Follow-up was reported in four of these cases and heart block recurred in three of them. A permanent pacemaker was the eventual treatment in 22 cases. The etiology of lupus-associated complete heart block is not clear. It is probably variable, possibly related to effects of autoantibodies reacting with the conduction system, myocardial disease and adverse effects of antimalarials. Insertion of a permanent pacemaker seems to be the preferable method of treatment.

Cardiac manifestations of Han Chinese patients with systemic lupus erythematosus: a retrospective study

OBJECTIVE

To investigate cardiac manifestations and the risk factors in Han Chinese patients with systemic lupus erythematosus (SLE).

METHODS

Seven hundred fifty SLE patients who were hospitalized at our department were recruited in the present study. The patients were divided into two groups-those with or without cardiac manifestations. Cardiac manifestations in those SLE patients, such as pericarditis, myocarditis, heart valve disease, arrhythmia, were analyzed. The risk and protective factors of cardiac diseases in patients with SLE, as well as the predictors of mortality, were assessed, respectively.

RESULTS

In all 750 SLE patients, there were 339 (45.20%) patients suffered from one or more cardiac manifestations, involving pericarditis in 9.5%, myocarditis in 5.7%, heart valve disease in 15.6%, arrhythmia in 16.67%, and cardiovascular diseases (CVD) in 14%. 15.7% of SLE patients were accompanied with pulmonary arterial hypertension (PAH), of which 13.7% were mild, 1.2% were moderate, and 0.8% were severe. No significant differences were found between the two groups in age, disease duration, gender, antibody, and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). The incidence of pericarditis, heart valve disease, arrhythmia, and PAH was positively correlated with age. The incidence of arrhythmia, CVD, and PAH was correlated with SLEDAI. PAH and myocarditis were the risk factors of mortality in SLE patients with disease duration ≤ 10 years (P = 0.034 and 0.001, respectively).

CONCLUSION

Cardiac involvement is common in Han Chinese SLE patients and associated with age and disease activity. PAH and myocarditis are the risk factors of mortality in SLE.

Association of Anti-Ro/Sjögren's syndrome type A Antibodies and Complete Atrioventricular Block in an Adult With Sjögren's Syndrome

A 57-year-old female patient with underlying hypertension, dyslipidemia, membranous glomerulonephritis, and Sjögren's syndrome presented to our clinic with near-syncope and dizziness symptoms. We detected non-conducted sinus beat in 12-lead electrocardiography. An echocardiography showed that the left ventricular systolic function was preserved without a regional wall abnormality. The patient did not have symptoms of congestive heart failure or recent myocardial infarction. We observed complete atrioventricular block with longest pause of 6.2 seconds in a 24-hour Holter electrocardiography, and subsequently implanted a permanent pacemaker. Anti-Ro/Sjögren's syndrome type A antibodies are commonly seen in Sjögren's syndrome and associated with a neonatal complete heart block. The pathogenesis of anti-Ro/Sjögren's syndrome type A antibodies in the conduction system of an adult heart is still uncertain. In this article, we report Sjögren's syndrome in an adult patient with complete atrioventricular block and membranous glomerulonephritis, which may be associated with a positive titer of anti-Ro/Sjögren's syndrome type A antibodies.

Complementary role of cardiovascular imaging and laboratory indices in early detection of cardiovascular disease in systemic lupus erythematosus

Background

Cardiovascular disease (CVD) has been documented in >50% of systemic lupus erythematosus (SLE) patients, due to a complex interplay between traditional risk factors and SLE-related factors. Various processes, such as coronary artery disease, myocarditis, dilated cardiomyopathy, vasculitis, valvular heart disease, pulmonary hypertension and heart failure, account for CVD complications in SLE.

Methods

Electrocardiogram (ECG), echocardiography (echo), nuclear techniques, cardiac computed tomography (CT), cardiovascular magnetic resonance (CMR) and cardiac catheterization (CCa) can detect CVD in SLE at an early stage. ECG and echo are the cornerstones of CVD evaluation in SLE. The routine use of cardiac CT and nuclear techniques is limited by radiation exposure and use of iodinated contrast agents. Additionally, nuclear techniques are also limited by low spatial resolution that does not allow detection of sub-endocardial and sub-epicardial lesions. CCa gives definitive information about coronary artery anatomy and pulmonary artery pressure and offers the possibility of interventional therapy. However, it carries the risk of invasive instrumentation. Recently, CMR was proved of great value in the evaluation of cardiac function and the detection of myocardial inflammation, stress-rest perfusion defects and fibrosis.

Results

An algorithm for CVD evaluation in SLE includes clinical, laboratory, ECG and echo assessment as well as CMR evaluation in patients with inconclusive findings, persistent cardiac symptoms despite normal standard evaluation, new onset of life-threatening arrhythmia/heart failure and/or as a tool to select SLE patients for CCa.

Conclusions

A non-invasive approach including clinical, laboratory and imaging evaluation is key for early CVD detection in SLE.

Cardiac involvement in systemic lupus erythematosus

Pericarditis is the most common cardiac abnormality in systemic lupus erythematosus (SLE) patients, but lesions of the valves, myocardium and coronary vessels may all occur. In the past, cardiac manifestations were severe and life threatening, often leading to death. Therefore, they were frequently found in post-mortem examinations. Nowadays cardiac manifestations are often mild and asymptomatic. However, they can be frequently recognized by echocardiography and other noninvasive tests. Echocardiography is a sensitive and specific technique in detecting cardiac abnormalities, particularly mild pericarditis, valvular lesions and myocardial dysfunction. Therefore, echocardiography should be performed periodically in SLE patients. Vascular occlusion, including coronary arteries, may develop due to vasculitis, premature atherosclerosis or antiphospholipid antibodies associated with SLE. Premature atherosclerosis is the most frequent cause of coronary artery disease (CAD) in SLE patients. Efforts should be made to control traditional risk factors as well as all other factors which could contribute to atherosclerotic plaque development.

The Cardiac Safety of Chloroquine Phosphate Treatment in Patients with Systemic Lupus Erythematosus: The Influence on Arrhythmia, Heart Rate Variability and Repolarization Parameters

Antimalarials are used to treat cutaneous and systemic lupus erythematosus (SLE). Even though cardiac damage is a rare complication, over the last decade several reports have raised the issue of cardiotoxicity associated with antimalarials. Therefore, the aim of study was to evaluate the influence of seven-month chloroquine treatment with a 250 mg daily dose on arrhythmia, conduction disturbances as well as heart rate variability and repolarization parameters assessed in 24-hour Holter monitoring. The studied group included 28 SLE patients treated with chloroquine as a monotherapy. In all the patients standard 12 leads surface ECG (50 mm) and the 24-hour ECG Holter monitoring (Oxford Medilog Excel-2) were performed before and after chloroquine phosphate treatment. All subjects presented sinus rhythm both at the enrollment and after treatment. No episodes of paroxysmal arrhythmias or conduction disturbances were reported during the study. All the patients were characterized by tendency to tachycardia, but no significant differences in mean heart rate were found before and after chloroquine administration. Similarly, no changes in heart rate variability or repolarization parameters were observed.

Left Atrial Inexcitability in Children With Congenital Lupus-Induced Complete Atrioventricular Block

Background

Congenital atrioventricular block is a well‐established immunologic complication of maternal systemic lupus erythematosus. We sought to further characterize the electrophysiological manifestations of maternal systemic lupus erythematosus on neonatal atria.

Methods and Results

Cases of isolated congenital atrioventricular block treated at our center over the past 41 years were identified. Data were extracted from clinical charts, pacemaker interrogations, ECGs, echocardiograms, and histopathological reports, when available. Of 31 patients with isolated congenital atrioventricular block, 18 were negative for maternal antibodies and had normal epicardial atrial sensing and pacing thresholds. In contrast, 12 of 13 patients with positive maternal antibodies had epicardial pacemakers, 5 (42%) of whom had left atrial (LA) inexcitability and/or atrial conduction delay. In 3 patients, the LA could not be captured despite high‐output pacing. The fourth patient had acutely successful LA appendage and left ventricular lead placement. At early follow‐up, an increased delay between the surface P‐wave and intracardiac atrial depolarization was observed, indicative of atrial conduction delay. The fifth patient exhibited LA lead dysfunction, with atrial under‐sensing and an increased capture threshold, 2 weeks after implantation. Biopsies of LA appendages performed in 2 patients showed no evidence of atrial fibrosis or loss of atrial myocytes.

Conclusions

Herein, we report previously undescribed yet prevalent electrophysiological ramifications of maternal systemic lupus erythematosus, which extend beyond congenital atrioventricular block to encompass alterations in LA conduction, including LA inexcitability. These manifestations can complicate epicardial pacemaker implantation in newborns. In the absence of histological evidence of extensive atrial fibrosis, immune‐mediated functional impairment of electrical activity is suspected.

Anti-Ro/SSA antibodies and cardiac rhythm disturbances: Present and future perspectives

Several case reports, small case series, and original research papers have recently suggested that the action of certain auto-antibodies related to connective tissue diseases may be responsible for significant cardiac rhythm disturbances in adults. The relationship between anti-Ro/SSA antibodies and congenital complete atrioventricular block is well recognized in the fetal heart. Herein we review the emerging evidences of the link to increased levels of anti-Ro/SSA antibodies with rhythm disorders of unknown origin in the adult. Confirmation of this distinct etiology may eventually be the basis for new therapies.

Atrioventricular heart block and syncope coincident with diagnosis of systemic lupus erythematosus

We describe a 59-year-old woman with cardiac conduction abnormalities caused by lupus-induced myocardial damage. She had a history of arthralgias and antinuclear antibodies but no clinical history of systemic lupus erythematosus. She presented with syncope and Mobitz type II second-degree atrioventricular block. Anti-double-stranded DNA antibodies developed coincident with the identification of heart block. Cardiac magnetic resonance imaging showed late enhancing foci of gadolinium uptake that anatomically correlated with her conduction abnormalities. We conclude that her conduction disease represents an early and structural cardiac manifestation of systemic lupus erythematosus that is unusual in its presentation at the time of initial diagnosis.

Cardio-renal syndrome type 5: epidemiology, pathophysiology, and treatment

The cardio-renal syndromes (CRS) recently were defined systematically as disorders of the heart or kidney whereby dysfunction of one organ leads to dysfunction of another. Five types of CRS are defined. The first four types describe acute or chronic cardio-renal or renocardiac syndromes. Type 5 CRS refers to secondary cardio-renal syndrome or cardio-renal involvement in systemic conditions. It is a clinical and pathophysiological entity to describe the concomitant presence of renal and cardiovascular dysfunction. Type 5 CRS can be acute or chronic and it does not strictly satisfy the definition of CRS. However, it encompasses many conditions in which combined heart and kidney dysfunction is observed. Because this entity has been described only recently there is limited information about the epidemiology, clinical course, and treatment of this condition.

Contributions of mass spectrometry-based proteomics to defining cellular mechanisms and diagnostic markers for systemic lupus erythematosus

Systematic lupus erythematosus (SLE) is a complex disease for which molecular diagnostics are limited and pathogenesis is not clearly understood. Important information is provided in this regard by identification and characterization of more specific molecular and cellular targets in SLE immune cells and target tissue and markers of early-onset and effective response to treatment of SLE complications. In recent years, advances in proteomic technologies and applications have facilitated such discoveries. Here we provide a review of insights into SLE pathogenesis, diagnosis and treatment that have been provided by mass spectrometry-based proteomic approaches.

Sinus node dysfunction as an initial presentation of adult systemic lupus erythematosus

Cardiac involvement in systemic lupus erythematosus (SLE) has been well described. However, sinus node involvement with profound sinus bradycardia as an early manifestation of adult SLE has not been reported. A 27-year-old previously healthy female was admitted due to intermittent fever for 4 days. SLE was diagnosed based on clinical manifestations and laboratory data. Profound sinus bradycardia (heart rate = 41/min) with weakness was noted during hospitalization. ECG abnormalities completely resolved after a high-dose intravenous steroid infusion. Sinus node involvement with significant bradycardia is one of the possible complications in the early stage of adult SLE. Close cardiovascular monitoring and serial ECGs are suggested for early detection of this serious complication of adult SLE.

Anti-Ro/SSA antibodies and cardiac arrhythmias in the adult: facts and hypotheses

It is well established that the passive trans-placental passage of anti-Ro/SSA antibodies from mother to foetus is associated with the risk to develop an uncommon syndrome named neonatal lupus (NLE), where the congenital heart block represents the most severe clinical feature. Recent evidence demonstrated that also adult heart, classically considered invulnerable to the anti-Ro/SSA antibodies, may represent a target of the arrhythmogenicity of these autoantibodies. In particular, the prolongation of the QTc interval appears the most frequent abnormality observed in adults with circulating anti-Ro/SSA antibodies, with some data suggesting an association with an increased risk of ventricular arrhythmias, also life threatening. Moreover, even though the association between anti-Ro/SSA antibodies and conduction disturbances is undoubtedly less evident in adults than in infants, from the accurate dissection of the literature data the possibility arises that sometimes also the adult cardiac conduction tissue may be affected by such antibodies. The exact arrhythmogenic mechanisms involved in foetus/newborns and adults, respectively, have not been completely clarified as yet. However, increasing evidence suggests that anti-Ro/SSA antibodies may trigger rhythm disturbances through an inhibiting cross-reaction with several cardiac ionic channels, particularly the calcium channels (L-type and T-type), but also the potassium channel hERG, whose different expression and involvement in the cardiac electrophysiology during lifespan might account for the occurrence of age-related differences.

Clinical characteristics of lupus myocarditis in Korea

Clinically important myocarditis is an unusual feature in systemic lupus erythematosus (SLE). We describe the clinical characteristics, management and outcomes of five SLE patients who developed severe left ventricular dysfunction. Four patients were female with mean age of 36.4 years. Three patients had both lupus myocarditis and lupus nephritis. Four patients had raised anti-dsDNA antibody titer and low complement level and two patients had positive IgG anticardiolipin antibody. Three patients were treated by high-dose corticosteroids, one patient by intravenous pulse methylprednisolone, and one patient by intravenous immunoglobulin and pulse cyclophosphamide with high dose corticosteroids. Left ventricular function improved markedly in four patients and all of them had no recurrence of lupus myocarditis up to follow-up of 33 months. However, one patient, who showed no improvement of left ventricular function, was expired due to sudden cardiac arrest. Lupus myocarditis should be treated by immunosuppressive therapy with high-dose corticosteroids and mostly the prognosis might be good with early treatment.

Outcome of infants from mothers with anti-SSA/Ro antibodies

OBJECTIVE

To evaluate the incidence of electrocardiographic and laboratory abnormalities in neonates born from mothers with connective tissue disease and positive for anti-SSA/Ro antibodies.

STUDY DESIGN

Electrocardiogram, blood cell counts, liver and renal function tests prospectively obtained from 51 infants born from anti-SSA/Ro-positive mothers with connective tissue disease were compared with those obtained from 50 control infants born from mothers with anti-extractable nuclear antigen (ENA)-negative connective tissue disease. One infant with congenital complete heart block was excluded from analysis.

RESULTS

No infant showed sinus bradycardia. A first-degree atrioventricular block at birth was observed in five study group and no control group infants, P=0.023. Atrioventricular blocks spontaneously reverted or remained stable during the first year of life. Mean corrected QT value of infants born from anti-SSA/Ro-positive mothers was slightly prolonged as compared with the control group (0.404+/-0.03 s vs 0.395+/-0.02 s; P=0.060).

CONCLUSIONS

Infants exposed to anti-SSA/Ro antibodies had a significantly higher prevalence of first-degree atrioventricular block. At variance with previous studies, we observed a low frequency of hematologic abnormalities and no cases of hepatobiliary disease.

[Complete auriculoventricular block during chloroquine treatment]

INTRODUCTION

The cardiac toxicity of antimalarial agents is rare, it includes conduction disorders which can be complicated by third atrioventricular block and hypertrophic cardiomyopathy. We report two observations of patients who presented a complete heart block after several years of treatment by chloroquine.

CASE REPORT

Two patients followed for rheumatoid polyarthritis, treated by antimalarial agents for average 12 years and corticotherapy, presented a syncopal complete heart block which required an implantation of a pace maker. After having eliminated all the other underlying causes for complete heart block, the antimalarial agents were accused and were stopped. The clinical evolution after interruption of the treatment was favorable.

CONCLUSION

Our observations illustrate rare cardiac side effects observed in our two patients after long-term treatment by antimalarial agents. The diagnosis of antimalarial agents responsibility was retained on clinical and biological arguments after having eliminated the other causes. The insidious character of these complications imposes vigilance during the use of long-term treatment by antimalarial agents.

[Complete auriculoventricular blockage in adult patients with systemic lupus erythematosus. Case series and a review of the literature]

BACKGROUND AND OBJECTIVE

Congenital complete atrioventricular heart block (CHB) is due to the lesion of the cardiac conduction system by specific transplacental antibodies of maternal origin. In adults with systemic lupus erythematosus (SLE), cardiac toxicity is very questionable and has been related to treatment with synthetic antimalarial drugs (AM). Here we evaluate, in our geographic area, the presence of non congenital CHB in adult patients with SLE and its possible association with AM treatment.

PATIENTS AND METHODS

The frequency of CHB has been studied revising the clinical records of 595 SLE patients followed at the Unit for Systemic Diseases.

RESULTS

Five women (0.8% of the total series) suffered from CHB (2 patients developed it during a lupic crisis). All were on treatment with AM (100 versus 60% of the rest of the series) and maintained a dose of 250 mg/day (except one, with a dose of 500 mg/day) for a mean period of 90 months. The accumulated mean dose of AM was 753 g. Three patients developed cardiac insufficiency; 2 nephropathy; 2 myopathy; and one maculopathy. As accompanying processes we detected Sjögren's syndrome (2) and hypothyroidism (3). The frequency of HLA DR3, positive in 80% of the cases, is higher than observed in the total series, 34% (p = 0.053).

CONCLUSIONS

We detected the presence of CHB in 0.8% of SLE patients. They were all treated with AM. We did not verify any relationship with anti-ENA (anti-Ro/La and anti-RNP) antibodies, as communicated by others, but rather a trend to the association with HLA DR3 (at the limit of statistical significance).

Variable atrioventricular block in systemic lupus erythematosus

Systemic lupus erythematosus (SLE), a connective tissue disease characterized by the production of auto-antibodies and immune complexes, can affect all organs including the heart. The involvement of the conduction system in SLE has been less commonly described. We report a case of an asymptomatic 45-year-old woman with SLE referred to the emergency department (ED) for thrombocytopenia, and was found to have alternating first- and second-degree atrioventricular block (AVB) during routine electrocardiographic screening for hospital admission. Serial electrocardiograms (ECG) done in the ED when compared to those recorded 24 h prior revealed progression from mild first-degree AVB (PR interval = 216 ms) to significant first-degree AVB (PR interval = 510 ms), followed by second-degree AVB (Mobitz type I-Wenckebach phenomenon). The conduction abnormalities recorded over a 28-h period resolved with corticosteroid treatment. Review of the literature on the disruption of the cardiac conduction system in SLE is discussed.