Predicting worsening heart failure hospitalizations in patients with implantable cardioverter defibrillators: is it all about alerts? A pooled analysis of nine trials

AIMS

To predict worsening heart failure hospitalizations (WHFHs) in patients with implantable defibrillators and remote monitoring, the HeartInsight algorithm (Biotronik, Berlin, Germany) calculates a heart failure (HF) score combining seven physiologic parameters: 24 h heart rate (HR), nocturnal HR, HR variability, atrial tachyarrhythmia, ventricular extrasystoles, patient activity, and thoracic impedance. We compared temporal trends of the HF score and its components 12 weeks before a WHFH with 12-week trends in patients without WHFH, to assess whether trends indicate deteriorating HF regardless of alert status.

METHODS AND RESULTS

Data from nine clinical trials were pooled, including 2050 patients with a defibrillator capable of atrial sensing, ejection fraction ≤ 35%, NYHA class II/III, no long-standing atrial fibrillation, and 369 WHFH from 259 patients. The mean HF score was higher in the WHFH group than in the no WHFH group (42.3 ± 26.1 vs. 30.7 ± 20.6, P < 0.001) already at the beginning of 12 weeks. The mean HF score further increased to 51.6 ± 26.8 until WHFH (+22% vs. no WHFH group, P = 0.003). As compared to the no WHFH group, the algorithm components either were already higher 12 weeks before WHFH (24 h HR, HR variability, thoracic impedance) or significantly increased until WHFH (nocturnal HR, atrial tachyarrhythmia, ventricular extrasystoles, patient activity).

CONCLUSION

The HF score was significantly higher at, and further increased during 12 weeks before WHFH, as compared to the no WHFH group, with seven components showing different behaviour and contribution. Temporal trends of HF score may serve as a quantitative estimate of HF condition and evolution prior to WHFH.

Activities of Clinical Expertise and Research in a Rare Disease Referral Centre: A Place for Telemedicine beyond the COVID-19 Pandemic?

INTRODUCTION

Rare disease referral centres are entrusted with missions of clinical expertise and research, two activities that have to contend with numerous obstacles. Providing specialist opinions is time-consuming, uncompensated and limited by difficulties in exchanging medical data. Clinical research is constrained by the need for frequent research protocol visits. Our objective was to determine whether telemedicine (TLM) can overcome these difficulties.

METHODS

To better characterise the activity of clinical expertise provided by our French centre, each opinion delivered by our team was reported on a standardised form. To investigate our clinical research activity, investigators and patients were asked to complete a questionnaire on the acceptability of research protocol teleconsultations.

RESULTS

Regarding clinical expertise, our team delivered 120 opinions per week (representing a total of 21 h), of which 29% were delivered to patients and 69% to medical practitioners. If these were delivered using TLM, it would represent a potential weekly income of EUR 500 (tele-expertise) and EUR 775 (teleconsultations). Regarding the research activity, 70% of investigators considered the frequency of visits to be a limiting factor for patient inclusions; nearly half of the patients surveyed would be in favour of having teleconsultations in place of (40%) or in addition to (56%) in-person visits.

CONCLUSION

Whereas TLM has become widely used as a back-up procedure to in-person consultations during the COVID-19 pandemic, the solutions it provides to the problems encountered in performing expertise and research activities have made it a new conventional follow-up modality for patients with rare diseases.

Usefulness of remote monitoring for the early detection of back-up mode in implantable cardioverter defibrillators

BACKGROUND

Reversion of an implantable cardioverter defibrillator (ICD) to back-up mode degrades the operating capabilities of the device, puts patients at risk and requires rapid intervention by a manufacturer's technician.

AIM

To illustrate the usefulness of remote monitoring of ICDs for the early detection of reversion to back-up mode.

METHODS

In our centre, all patients implanted with an ICD, with or without resynchronisation, were offered remote monitoring as soon as the technology became available. Alerts triggered by the remote monitoring system were included prospectively in a register. During a mean follow-up of 5.7±1.3 years, a total of 1594 patients with an ICD (441 with resynchronisation function) followed with remote monitoring were included in the register.

RESULTS

Among 15,874 alerts, only 10 were related to a reversion to back-up mode. Among those, seven reversions were caused by radiotherapy, two were fake events and one was caused by magnetic resonance imaging. Except for the two fake events, the eight other patients had an emergency admission for the resetting and reprogramming of their ICD. None of the reversion to back-up mode alerts was followed by a clinical alert (i.e. a shock alert) before the ICD problem was resolved.

CONCLUSIONS

Reversion to back-up mode is a very rare event, accounting for 0.06% of total alerts; remote monitoring facilitates the early detection of this critical event to resolve the problem faster than the next scheduled follow-up. Remote monitoring can prevent serious damage to the patient and avoids systematic ambulatory control of the ICD after each radiotherapy session.

Daily remote monitoring of implantable cardioverter-defibrillators: insights from the pooled patient-level data from three randomized controlled trials (IN-TIME, ECOST, TRUST)

Aims

Remote monitoring of implantable cardioverter-defibrillators may improve clinical outcome. A recent meta-analysis of three randomized controlled trials (TRUST, ECOST, IN-TIME) using a specific remote monitoring system with daily transmissions [Biotronik Home Monitoring (HM)] demonstrated improved survival. We performed a patient-level analysis to verify this result with appropriate time-to-event statistics and to investigate further clinical endpoints.

Methods and results

Individual data of the TRUST, ECOST, and IN-TIME patients were pooled to calculate absolute risks of endpoints at 1-year follow-up for HM vs. conventional follow-up. All-cause mortality analysis involved all three trials (2405 patients). Other endpoints involved two trials, ECOST and IN-TIME (1078 patients), in which an independent blinded endpoint committee adjudicated the underlying causes of hospitalizations and deaths. The absolute risk of death at 1 year was reduced by 1.9% in the HM group (95% CI: 0.1–3.8%; P = 0.037), equivalent to a risk ratio of 0.62. Also the combined endpoint of all-cause mortality or hospitalization for worsening heart failure (WHF) was significantly reduced (by 5.6%; P = 0.007; risk ratio 0.64). The composite endpoint of all-cause mortality or cardiovascular (CV) hospitalization tended to be reduced by a similar degree (4.1%; P = 0.13; risk ratio 0.85) but without statistical significance.

Conclusion

In a pooled analysis of the three trials, HM reduced all-cause mortality and the composite endpoint of all-cause mortality or WHF hospitalization. The similar magnitudes of absolute risk reductions for WHF and CV endpoints suggest that the benefit of HM is driven by the prevention of heart failure exacerbation.

[Telemonitoring by the nurse of patients equipped with an implantable heart device]

The nurse is at the heart of the caregiving relationship in the remote monitoring of patients with heart failure equipped with an implantable device. Her direct contact with the patient erases the distance imposed by telemonitoring and her close connection with the cardiologist-arrhythmia specialist ensures the patient follow-up is optimal. After her training in telemedicine, the nurse plays a key role in the telerhythmology activity.

Potential role of antitachycardia pacing alerts for the reduction of emergency presentations following shocks in patients with implantable cardioverter-defibrillators: implications for the implementation of remote monitoring

AIMS

Despite increased use of remote monitoring (RM) to follow up implantable cardioverter-defibrillator (ICD) recipients, many patients still receive ICD shocks in the community and present to the emergency department. Our aim was to identify the best predictors of impending shock delivery that can be measured with an ICD and to identify the most appropriate activities to alert physicians to during RM follow-up.

METHODS AND RESULTS

All patients presenting to our institution for ICD shock, from November 2011 to November 2014, were enrolled in this prospective study. Patient characteristics, investigation results, and details of electrical activities from ICD interrogation were recorded at presentation. Presentations were classified as potentially avoidable if activities from a list of set criteria were apparent more than 48 h before index shock. Univariate and multivariate analyses were then used to identify predictors of potentially avoidable shocks. In total, 109 emergency presentations were recorded in 90 patients (male: 85%; 57 ± 16 years; ischaemic cardiomyopathy: 49%; LVEF: 34 ± 13%; electrical storm: 40%), of which 26 (24%) were potentially avoidable. Antitachycardia pacing (ATP) episodes were the most important predictor of impending shock. Potentially avoidable shocks were preceded by more episodes of ATP than unavoidable shocks (13 [3-67] vs. 3 [0-10]; P < 0.001). Patients followed up with RM systems configured to generate alerts following ATP delivery experienced significantly less ICD shocks (24 vs. 16%, P < 0.01).

CONCLUSION

Remote monitoring systems that generate alerts following ATP delivery could reduce emergency presentations for ICD shock by 24%, as ATP is a key predictor of impending shock delivery.

Remote monitoring of patients with implantable cardioverter-defibrillators: can results from large clinical trials be transposed to clinical practice?

BACKGROUND

Remote monitoring (RM) is increasingly used to follow up patients with implantable cardioverter-defibrillators (ICDs). Randomized control trials provide evidence for the benefit of this intervention, but data for RM in daily clinical practice with multiple-brands and unselected patients is lacking.

AIMS

To assess the effect of RM on patient management and clinical outcome for recipients of ICDs in daily practice.

METHODS

We reviewed ICD recipients followed up at our institution in 2009 with RM or with traditional hospital only (HO) follow-up. We looked at the effect of RM on the number of scheduled ambulatory follow-ups and urgent unscheduled consultations, the time between onset of asymptomatic events to clinical intervention and the clinical effectiveness of all consultations. We also evaluated the proportion of RM notifications representing clinically relevant situations.

RESULTS

We included 355 patients retrospectively (RM: n=144, HO: n=211, 76.9% male, 60.3±15.2 years old, 50.1% with ICDs for primary prevention and mean left ventricular ejection fraction 35.5±14.5%). Average follow-up was 13.5 months. The RM group required less scheduled ambulatory follow-up consultations (1.8 vs. 2.1/patient/year; P<0.0001) and a far lower median time between the onset of asymptomatic events and clinical intervention (7 vs. 76 days; P=0.016). Of the 784 scheduled ambulatory follow-up consultations carried out, only 152 (19.4%) resulted in therapeutic intervention or ICD reprogramming. We also found that the vast majority of RM notifications (61.9%) were of no clinical relevance.

CONCLUSION

RM allows early management of asymptomatic events and a reduction in scheduled ambulatory follow-up consultations in daily clinical practice, without compromising safety, endorsing RM as the new standard of care for ICD recipients.

Decreased delivery of inappropriate shocks achieved by remote monitoring of ICD: a substudy of the ECOST trial

INTRODUCTION

Inappropriate shocks remain a highly challenging complication of implantable cardioverter defibrillators (ICD). We examined whether automatic wireless remote monitoring (RM) of ICD, by providing early notifications of triggering events, lowers the incidence of inappropriate shocks.

METHODS AND RESULTS

We studied 433 patients randomly assigned to RM (n = 221; active group) versus ambulatory follow-up (n = 212; control group). Patients in the active group were seen in the ambulatory department once a year, unless RM reported an event requiring an earlier ambulatory visit. Patients in the control group were seen in the ambulatory department every 6 months. The occurrence of first and further inappropriate shocks, and their causes in each group were compared. The characteristics of the study groups, including pharmaceutical regimens, were similar. Over a follow-up of 27 months, 5.0% of patients in the active group received ≥1 inappropriate shocks versus 10.4% in the control group (P = 0.03). A total of 28 inappropriate shocks were delivered in the active versus 283 in the control group. Shocks were triggered by supraventricular tachyarrhythmias (SVTA) in 48.5%, noise oversensing in 21.2%, T wave oversensing in 15.2%, and lead dysfunction in 15.2% of patients. The numbers of inappropriate shocks delivered per patient, triggered by SVTA and by lead dysfunction, were 74% and 98% lower, respectively, in the active than in the control group.

CONCLUSION

RM was highly effective in the long-term prevention of inappropriate ICD shocks.

Costs of remote monitoring vs. ambulatory follow-ups of implanted cardioverter defibrillators in the randomized ECOST study

AIMS

The Effectiveness and Cost of ICD follow-up Schedule with Telecardiology (ECOST) trial evaluated prospectively the economic impact of long-term remote monitoring (RM) of implantable cardioverter defibrillators (ICDs).

METHODS AND RESULTS

The analysis included 310 patients randomly assigned to RM (active group) vs. ambulatory follow-ups (control group). Patients in the active group were seen once a year unless the system reported an event mandating an ambulatory visit, while patients in the control group were seen in the ambulatory department every 6 months. The costs of each follow-up strategy were compared, using the actual billing documents issued by the French health insurance system, including costs of (i) (a) ICD-related ambulatory visits and transportation, (b) other ambulatory visits, (c) cardiovascular treatments and procedures, and (ii) hospitalizations for the management of cardiovascular events. The ICD and RM system costs were calculated on the basis of the device remaining longevity at the end of the study. The characteristics of the study groups were similar. Over a follow-up of 27 months, the mean non-hospital costs per patient-year were €1695 ± 1131 in the active, vs. €1952 ± 1023 in the control group (P = 0.04), a €257 difference mainly due to device management. The hospitalization costs per patient-year were €2829 ± 6382 and €3549 ± 9714 in the active and control groups, respectively (P = 0.46). Adding the ICD to the non-hospital costs, the savings were €494 (P = 0.005) or, when the monitoring system was included, €315 (P = 0.05) per patient-year.

CONCLUSION

From the French health insurance perspective, the remote management of ICD patients is cost saving.

CLINICAL TRIALS REGISTRATION

NCT00989417, www.clinicaltrials.gov.

Pregnancy in women with an implantable cardioverter-defibrillator: is it safe?

AIMS

To describe obstetric/neonatal and cardiac outcomes for a cohort of women carrying implantable cardioverter-defibrillators (ICDs) during pregnancy.

METHODS AND RESULTS

All women in routine follow-up at our institution for ICD implantation who became pregnant between 2006 and 2013 were included in this study. All ICDs were pre-pectoral devices with bipolar endocardial leads. Obstetric/neonatal and cardiac outcomes were assessed during pregnancy and post-partum. Twenty pregnancies were conceived by 12 women carrying ICD devices, 14 of which resulted in live births and none in maternal death. Seven of these women had structural cardiomyopathies and five had channelopathies. No device-related complications were recorded. Twelve shocks (nine transthoracic and three from ICDs) were experienced during pregnancy by two women, one of whom miscarried shortly afterwards at 4 weeks gestation. One stillbirth, three miscarriages and one termination were recorded for women with long QT syndrome, repaired tetralogy of Fallot and repaired Laubry-Pezzi syndrome, respectively. Intrauterine growth restriction, low birth weight, and neonatal hypoglycaemia were recorded in four, three, and five pregnancies, respectively.

CONCLUSIONS

Pregnancy had no effect on ICD operation and no evidence was found to link ICD carriage with adverse pregnancy outcomes, although one miscarriage may have been induced by ICD shock therapy. A worsening of cardiac condition occurs in specific cardiac diseases and β-blocker therapy should be continued for all women carrying ICDs in pregnancy as the benefits outweigh the risks of taking this medication.

A randomized study of remote follow-up of implantable cardioverter defibrillators: safety and efficacy report of the ECOST trial

AIMS

The ECOST trial examined prospectively the long-term safety and effectiveness of home monitoring (HM) of implantable cardioverter defibrillators (ICD).

METHODS AND RESULTS

The trial's primary objective was to randomly compare the proportions of patients experiencing ≥ 1 major adverse event (MAE), including deaths from all causes, and cardiovascular, procedure-related, and device-related MAE associated with HM (active group) vs. ambulatory follow-ups (control group) in a sample of 433 patients. The 221 patients assigned to the active group were seen once a year, unless HM reported an ICD dysfunction or a clinical event requiring an ambulatory visit, while the 212 patients in the control group underwent ambulatory visits every 6 months. The characteristics of the study groups were similar. Over a follow-up of 24.2 months, 38.5% of patients in the active and 41.5% in the control group experienced ≥ 1 MAE (P < 0.05 for non-inferiority). The overall number of shocks delivered was significantly lower in the active (n = 193) than in the control (n = 657) group (P < 0.05) and the proportion of patients who received inappropriate shocks was 52% lower in the active (n = 11) than in the control (n = 22) group (P < 0.05). At the end of the follow-up, the battery longevity was longer in the active group because of a lower number of capacitor charges (499 vs. 2081).

CONCLUSION

Our observations indicate that long-term HM of ICD is at least as safe as standard ambulatory follow-ups with respect to a broad spectrum of MAE. It also lowered significantly the number of appropriate and inappropriate shocks delivered, and spared the device battery. Clinical trials registration NCT00989417.

Temporal analysis of heart rate variability as a predictor of post traumatic stress disorder in road traffic accidents survivors

BACKGROUND

Road Traffic Accidents (RTA) are most probably the leading cause of post traumatic stress disorder (PTSD) in developed countries. The autonomic nervous system (ANS) disturbances, due to psychological trauma, are part of the pathophysiology of PTSD. The aim of the present study was to determine whether early heart rate variability (HRV) measurement, a biomarker of the ANS function, could act as a predictor of PTSD development after a RTA.

METHODS

We prospectively investigated 35 survivors of RTA with both physical injury and psychological trauma. HRV data were obtained from 24-h Holter ECG monitoring, which was performed on the second day after the accident. Time domain analysis was applied to the inter-beat (RR) interval time series to calculate the various parameters of HRV. PTSD status was assessed 2 and 6 months after RTA.

RESULTS

There was a global diminution of HRV measurements in the PTSD group at both 2 and 6 months. The variability index was the best predictor of PTSD with the area under the receiveroperating curve for discriminating PTSD at 6 months at 0.92 (95% CI: 0.785; 1.046). A cut-off at 2.19% yielded a sensitivity of 85.7% and a specificity of 81.8% for PTSD. Positive and negative predictive values were respectively 75% and 90%. However, initial heart rate (HR) data were relevant at 2 months but not at 6 months.

CONCLUSION

RTA survivors exhibiting lower parasympathetic modulation of HR, indexed by temporal analysis of HRV, are more susceptible to developing PTSD as a short and long-term outcome.

Contributions of remote monitoring to the follow-up of implantable cardioverter-defibrillator leads under advisory

Aims

Automatic daily transmission of data from implantable cardioverter–defibrillators (ICDs) enables the remote monitoring of device status and leads function. We report on a 2-year experience with remote monitoring in 40 recipients of high-voltage ICD leads, prone to fracture and under advisory since October 2007.

Methods and results

The ICDs were remotely monitored as well as systematically interrogated in the ambulatory department every 3 months. The patients were also seen in case of abnormal lead impedance, or other manifestations consistent with lead dysfunction. Over a mean follow-up of 22 ± 4 months after ICD implantation, four lead dysfunctions were suspected because of remotely transmitted oversensing of noise artifacts, abrupt rise in pacing impedance, or both. A lead fracture needing lead replacement was confirmed in three patients (7.5%), two of them before any inappropriate therapy and one after the delivery of three inappropriate shocks. No lead failure was observed in the remaining 36 patients, either at the time of ambulatory visits or during remote monitoring.

Conclusion

Remote monitoring allowed the early and reliable detection of ICD leads failure without requiring any patient intervention.

Impact of the control of symptomatic paroxysmal atrial fibrillation on health-related quality of life

AIMS

Patients with atrial fibrillation (AF) consider the related symptoms disruptive to their quality of life (QoL). This study aimed to evaluate the impact of the control of symptomatic paroxysmal AF (PAF) on QoL.

METHODS AND RESULTS

Patients with symptomatic PAF were treated for 48 weeks with open-label flecainide acetate controlled release (Flec CR). Quality of life was assessed by SF-36 and Atrial Fibrillation Severity Scale scores at baseline, Week 12 (W12), W24, and W48. Of the 229 treated patients, 217 were analysed for QoL (123 with controlled and 94 with uncontrolled symptomatic PAF at inclusion). The controlled group had a similar or better QoL (SF-36) at baseline compared with a reference population (significantly better for: physical functioning, bodily pain, and physical component). The uncontrolled group had an inferior QoL (significantly worse for: role physical, general health, vitality, role emotional, social functioning, mental health, and mental component). When treated with Flec CR, the controlled group baseline QoL scores were maintained and the uncontrolled group scores were improved to a level comparable to the controlled group scores. Safety findings reflect the known clinical safety profile of flecainide acetate.

CONCLUSION

In this study, patients with uncontrolled symptomatic PAF at baseline had an inferior QoL to those with controlled symptomatic PAF. Following treatment with controlled-release flecainide acetate, their QoL improved to a level comparable to controlled patients.

[Atrial fibrillation: challenge of antithrombotic treatment]

Antithrombotic treatment is a crucial challenge in the management of patients with atrial fibrillation (AF). It is the only treatment which can decrease mortality in relation with AF. It can also prevent the first cause of dependency in elderly: stroke. Vitamin K antagonists are the more potent drugs to reduce the risk of ischemic stroke in patient with AF. Aspirin, unfractioned heparine or low molecular weight heparin and thienopyridine can also play a role in the antithrombotic therapy in special situations.

[Quality of life in atrial fibrillation patients. Clinical stakes]

Atrial fibrillation (AF) patients' quality of life (QOL), as measured with generic or disease-specific instruments, is impaired. Age, sex and comorbidity impact QOL scores in AF patients. Therapeutic interventions have tried to improve QOL in AF patients with mitigated results.

Recurrent unexplained syncope may have a cerebral origin: report of 10 cases of arrhythmogenic epilepsy

BACKGROUND

Despite thorough investigation, approximately 15-20% of syncope cases remain unexplained. An underrecognized cause of syncope may occur when partial epileptic discharges profoundly disrupt normal cardiac rhythm, including cardiac asystole, the so-called arrhythmogenic epilepsy (AE).

AIM

To report initial results of observations of AE in patients with recurrent, unexplained, traumatic and/or convulsive syncope.

METHODS

Ten patients aged 49+/-20 years (median 49.5 years; nine women) underwent complete cardiological (including ambulatory Holter electrocardiogram (ECG), echocardiography and head-up tilt test [plus electrophysiology in four patients]) and neurological (including standard electroencephalogram [EEG], computed tomography [CT] and magnetic resonance imaging scan [MRI]) assessments.

RESULTS

After initial evaluation, neurocardiogenic syncope was suspected in six patients with tilt-induced hypotension+/-bradycardia. Further evaluation (prolonged inpatient video-EEG/ECG monitoring) was undertaken because of non-diagnostic syncope or uncertainty about the diagnosis of neurocardiogenic syncope. While monitored in the neurophysiology lab, a syncopal episode similar to the spontaneous episodes recurred in all 10 patients. Cardiac asystole preceded by partial seizure of temporal onset was documented in nine patients; a second-degree atrioventricular (AV) block with a cardiac rhythm of 30 beats per minute preceded by partial seizure of temporal onset was noted in one patient. Eight patients were treated successfully with antiepileptic drugs; two were refractory to antiepileptic therapy and required pacemaker implantation. No patient had recurrent syncope during a median follow-up of 102.5 months (mean 82.2+/-42; range 16-128 months).

CONCLUSIONS

In patients with recurrent, unexplained, traumatic and/or convulsive syncope, AE should be considered as a possible aetiology.

Incidence of Early Adverse Events Surrounding Direct Current Cardioversion of Persistent Atrial Fibrillation. A Cohort Study of Practices

AIMS

To establish the incidence of early adverse events surrounding direct current (DC) cardioversion of persistent atrial fibrillation in an unselected patient cohort and to describe and analyse these complications.

METHODS

Prospective study over a three-month period (February, March and April 2000). Outcome measures included all serious adverse events during the hospitalisation for DC cardioversion. Six hundred and eighty-four DC cardioversion were performed on 659 patients.

RESULTS

The rate of adverse events was 4.4% including 1.3% bradycardia, 0.3% ventricular arrhythmia, 0.3% QT increase, 1% serious haemorrhages, 0.4% death and 1.2% miscellaneous adverse events.

CONCLUSION

The perceived tolerance to DC cardioversion in atrial fibrillation should be amended with the 4.4% serious early adverse events.

Absolute contraindications in relation to potential drug interactions in outpatient prescriptions: analysis of the first five million prescriptions in 1999

OBJECTIVES

Adverse drug interactions increase morbidity and mortality. To prevent these, situations leading to adverse prescriptions must be clarified. This study quantifies and analyses prescriptions with potential adverse drug interactions in primary health care in the North of France over a 3-month period.

METHODS

All prescriptions administered between 1 January 1999 and 31 March 1999 were analysed to identify potential interactions amongst drugs appearing on the same prescription sheet. The regional French healthcare database was compiled to further classify contraindications.

RESULTS

There were 5,358,374 prescriptions administered to 44% of the overall population of the Nord-Pas de Calais area (1,754,372 patients per 3,990,167 general population). There were 14,390 prescriptions classified as either absolute (26%) or relative contraindications (74%). Nine drug categories accounted for most of the absolute contraindications: dopaminergic antiparkinsonians, neuroleptic agents, migraine treatments (such as ergot alkaloids, sumatriptan and other triptan derivatives), prokinetic drugs (cisapride), antibacterial drugs (macrolides), antifungals (imidazoles), antiarrhythmics, beta-blockers and analgesics (opioids and floctafenine). In 54% of patients exposed, the incurred risk was either QT prolongation/Torsade de Pointes or antagonism of dopaminergic antiparkinson agents with dopamine receptor antagonists prescribed as antipsychotic agents.

CONCLUSIONS

Among a non-selected population of ambulatory outpatients, the number of quarterly prescriptions with contraindications with potentially harmful drug interactions is 27 in 10,000 prescriptions. This would extrapolate to nearly 200,000 contraindications on same-prescription sheets in France in the first quarter of 1999.

Absolute contraindications in relation to potential drug interactions in outpatient prescriptions: analysis of the first five million prescriptions in 1999

OBJECTIVES

Adverse drug interactions increase morbidity and mortality. To prevent these, situations leading to adverse prescriptions must be clarified. This study quantifies and analyses prescriptions with potential adverse drug interactions in primary health care in the north of France over a 3-month period.

METHODS

All prescriptions administered between 1 January and 31 March 1999 were analysed to identify potential interactions amongst drugs appearing on the same prescription sheet. The regional French healthcare database was compiled to further classify contra-indications.

RESULTS

There were 5,358,374 prescriptions administered to 44% of the overall population of the Nord-Pas de Calais area (1,754,372 patients/3,990,167 general population). There were 14,390 prescriptions classified as either absolute (26%) or relative contraindications (74%). Nine drug categories accounted for most of the absolute contraindications: dopaminergic antiparkinsonians, neuroleptic agents, migraine treatments (such as ergot alkaloids, sumatriptan and other triptan derivatives), prokinetic drugs (cisapride), antibacterial drugs (macrolides), antifungals (imidazoles), antiarrhythmics, betablockers and analgesics (opioids and floctafenine). In 54% of patients exposed, the incurred risk was either QT prolongation/Torsade de Pointes or antagonism of dopaminergic antiparkinson agents with dopamine receptor antagonists prescribed as antipsychotic agents.

CONCLUSIONS

Among a non-selected population of ambulatory outpatients, the number of quarterly prescriptions with contra-indications with potentially harmful drug interaction was 27 in 10,000 prescriptions. This would extrapolate to nearly 200,000 contra-indications on the same-prescription sheets in France in the first quarter of 1999.

Long-term evaluation of autonomic tone in patients below 50 years of age with unexplained cerebral infarction: relation to atrial vulnerability

Preliminary studies have described, in young patients with unexplained cerebral infarction, electrophysiological abnormalities similar to those observed in paroxysmal atrial fibrillation. Moreover, in young adults with 'normal' hearts, increased susceptibility to paroxysmal atrial fibrillation with autonomic abnormalities as assessed by heart rate variability analysis have been reported.

METHODS

The long-term time and frequency domain measures of heart rate variability were analysed prospectively from 24-h Holter ECG recordings in 25 patients (39 +/- 8 years) with unexplained cerebral infarction, and in 25 age-, sex- and cigarette-smoking-matched healthy control subjects. The day following the Holter ECG recordings, 9 +/- 4 months (mean) after the stroke, stroke patients underwent an electrophysiological study in order to analyse the electrical characteristics of their right atria and also to determine their vulnerability to atrial fibrillation. The correlations between autonomic tone parameters and electrophysiological findings were therefore assessed with linear regression analyses.

RESULTS

All the measured components of heart rate variability either in time (SDNN, pNN50, SDANN/5, rMSSD) or frequency domains (total power, low-frequency, high-frequency power, low-frequency/high-frequency power ratio) were similar between stroke patients and controls. During electrophysiological study, atrial fibrillation was induced in 80% of stroke patients. Among these patients, atrial refractory periods were significantly shorter, local electrograms were longer, and latent atrial vulnerability index was markedly decreased when compared with patients having no inducible atrial fibrillation. Concerning heart rate variability analysis, no difference was found between patients with induced atrial fibrillation when compared with a matched subgroup of healthy control subjects. Furthermore, there was no statistically linear correlation between any of the measured autonomic tone parameters and any of the discovered atrial vulnerability markers.

CONCLUSIONS

The long-term autonomic tone parameters of young patients presenting with a history of unexplained cerebral infarction are similar to those of healthy control subjects and are not correlated with atrial vulnerability parameters or atrial fibrillation inducibility.

Influence of mental stress and circadian cycle on postprandial lipemia

BACKGROUND

Mental stress produces alterations in serum lipids and lipoproteins.

OBJECTIVE

The objective was to assess the effect of mental stress during the day and night on postprandial lipoproteins.

DESIGN

Fourteen healthy subjects aged 26.6 +/- 5.0 y were given randomly the same meal either at night (0100) or during the day (1300), with or without (control session) a mental stress challenge. The meal contained 40% of estimated daily energy needs. The mental task was performed on a computer and consisted of a task of choice reaction. Blood samples were drawn at baseline and hourly for 7 h after the meal.

RESULTS

Urinary epinephrine concentrations were higher (P < 0.012) during the mental task than during the control sessions. Repeated-measures analysis of variance showed that mean postprandial triacylglycerol concentrations were significantly higher (P < 0.02) and total cholesterol (P < 0.0001) and HDL-cholesterol concentrations were significantly lower (P < 0.0001) at night than during the day. The mean postprandial VLDL-triacylglycerol concentration was significantly higher (P < 0.04) during the mental task than during the control sessions. Similarly, the VLDL-cholesterol response, calculated as the area under the postprandial curve, was significantly greater (P < 0.02) during the mental task than during the control sessions. There was no interaction between mental stress and nyctohemeral cycle on postprandial lipoprotein responses, suggesting that both indexes act independently on postprandial lipid metabolism.

CONCLUSIONS

Mental stress is associated with increased concentrations of postprandial triacylglycerol-rich lipoprotein fractions. Therefore, postprandial hyperlipidemia is one possible mechanism contributing to the higher risk of ischemic heart disease in stressed people.

Single center experience with femoral extraction of permanent endocardial pacing leads

Between March 1995 and June 1997, 128 leads were extracted from the hearts of 28 women and 50 men, 69 +/- 15 years of age (mean +/- SD, range 22-92 years). The indications for the procedure were: Accufix leads in 18 patients (14%), dysfunction or incompatibility with ICD in 16 (12%), endocarditis on the lead in 41 (32%), pulse generator pocket infection in 28 (22%), and pulse generator and/or lead erosion in 25 patients (19%). The extraction was performed with a snare (lasso), via a femoral vein as a first approach in 116 leads, and as an alternate approach, after extraction from the original site of implantation had failed, in 12 leads. The leads had been implanted for 62 +/- 48 months (range 1-205 months). A Cook sheath was used in 7, and a femoral approach traction in 20 instances. Of the 128 leads, 122 (95%) were completely extracted, and 2 (2%) were partially extracted (the distal electrode remaining attached to the myocardium), and 4 (3%) could not be removed. Four complications occurred: 2 tears of the tricuspid valve without clinical consequences, one separation of the lead's distal electrode which migrated into the hypogastric vein, and one hemorrhage at the femoral puncture site. There was no death or serious complication caused by lead extraction in this series.

[Is programmed ventricular stimulation still up to date in the medicinal evaluation of ventricular tachycardia?]

Despite considerable advances in the understanding of cardiac arrhythmia mechanisms, death in relation to ventricular tachyarrhythmias remains an important public health problem, and management of ventricular arrhythmias remains a perpetual challenge in clinical cardiology. In the last decade, the development and refinement of implantable cardioverter defibrillators and the progress in techniques of radiofrequency electrode catheter ablation and antiarrhythmic surgery have been revolutionary in the management of ventricular tachycardia. On the other hand, there have been major changes in the use of drug therapy since the publication of the results of the CAST study. Inclusion of mortality as an endpoint in clinical trials highlights the fact that some antiarrhythmic drugs may have the proclivity to exert fatal proarrhythmic reactions while also having the potential to control recurrences of ventricular tachycardia. All these changes that now need to be integrated into global approaches for ventricular arrhythmia control led us to wonder whether serial testing is still up to date in the management of ventricular tachycardia. After more than 20 years of clinical use, there is much concern about the use of serial drug testing to guide antiarrhythmic drug therapy for the management of life-threatening sustained ventricular tachyarrhythmias in light of recent advances in the management of cardiac arrhythmias. The purpose of this article is to discuss, within a relatively brief compass, the cumulative data from different lines of investigations, results of randomized clinical trials, recently acquired beliefs and meta-analytic findings concerning the present place of serial electrophysiologic drug testing in the management of ventricular tachycardia.

[Epidemiology of paroxysmal auricular fibrillation]

The epidemiology of paroxysmal atrial fibrillation (PAF) is poorly known because of the difficulties in setting up trials to study this condition. Its biannual incidence is about 2 per thousand. Its prevalence is 1 to 2% in a population of over 65 years of age. Paroxysmal atrial fibrillation is often asymptomatic. An initial episode of atrial fibrillation may remain a single event in a number of cases. Isolated paroxysmal atrial fibrillation progresses to permanent atrial fibrillation in about 20% of cases, usually if there is underlying cardiac disease. Rheumatic valve disease, cardiac failure, hypertension, previous myocardial infarction and cerebrovascular accidents are often associated with paroxysmal atrial fibrillation. Embolic complications are rare if paroxysmal atrial fibrillation is isolated.

Asystolic cardiac arrest during head-up tilt test: incidence and therapeutic implications

Occasionally, the cardioinhibitory response may be profound during tilt induced syncope. Whether this response is associated with more severe symptoms or predicts a poor response to pharmacotherapy remains controversial. The aim of this study was to characterize patients with vasovagally mediated asystole occurring during head-up tilt test and to evaluate the respective interests of sequential pacing and beta-blockers to treat them. We performed 60 degree tilt testing in 179 consecutive patients with unexplained syncope (91 women and 88 men, age 36.6 +/- 20.1 years). Asystole was defined as a ventricular pause > 5 seconds. All patients with tilt induced asystole received therapy with either beta-blockers or sequential pacing, the efficacy of which was evaluated with serial tilt tests. Of 77 patients with positive tilt test, 10 developed syncope related to asystole (mean duration 11.9 +/- 4.9 s), 2 with spontaneous recovery, and 8 with seizures needing a brief cardiopulmonary resuscitation. When compared with patients without asystole, asystolic patients had more severe symptoms (seizures: 6/10 vs 9/67, P = 0.05, injury 9/10 vs 27/67, P = 0.0048). In the first six patients in whom cardiac pacing was considered, syncope or presyncope still occurred despite atrioventricular pacing at 45 beats/min. Five of these 6 patients, as well as the remaining 4 asystolic patients, were tilted with beta-blockers: 3 patients became tilt-negative; 3 were significantly improved; and 3 did not respond. During follow-up (mean 22.7 +/- 11.7 months) with every patient taking beta-blockers and seven having a permanent pacemaker, no syncopal recurrence was observed. Tilt-induced asystole that may require resuscitative maneuvers occurs especially in patients with a history of seizures or injury. Therapy with beta-blockers in often effective to prevent induction of syncope as well as recurrences.

[Determinants of malignant vasovagal syncopes with asystole disclosed by the tilting test and therapeutic implications]

In order to evaluate the determinants of malignant vasovagal syncope with asystole revealed by the tilting test and to determine the possible therapeutic implications, 179 patients (91 women and 88 men, mean age 36.6 +/- 20.1 years) referred for the assessment of unexplained a were studied. The test was performed with a tilt of 60 degrees for 45 minutes. A bolus of isoprenaline (0.02 to 0.08 microgram/kg.min) was injected in the case of a negative passive test. Asystole was defined as a ventricular pause lasting > or = 5 seconds.

RESULTS

Ten (13%) of the 77 patients with a positive tilting test experienced a cardio-inhibitory reaction with prolonged asystole lasting an average of 11.9 +/- 4.9 seconds. Compared to the other 67 patients with a positive test, those with asystole were younger (23/9 +/- 14.8 years vs 32.9 +/- 18.5 years, NS) and had a more frequent history of convulsions (6/10 vs 9/67, p = 0.05) during spontaneous episodes and trauma (9/10 vs 27/67, p = 0.005). Implantation of a pacemaker was chosen first-line treatment for the first 6 patients. Their follow-up tilting tests remained positive (pre S = 4, S = 1) despite DDD stimulation of 45 bpm. Five of these patients and the following 4 patients were retested under beta-blockers. In six patients treated with beta-blockers, the clinical symptoms resolved completely (n = 3) or improved (n = 3), in contrast with 3 other patients in whom the tilting test remained positive with recurrence of asystole. The mean follow-up for the 169 patients is 22.7 +/- 11 months and the ten patients with asystole remained totally asymptomatic.

CONCLUSION

An asystolic response during the tilting test is characteristic of vasovagal syncope described as malignant. The syndrome essentially affects young patients, with a more frequent history of trauma and convulsions. Beta-blockers appear to be at least as effective as permanent pacemaker to prevent symptoms in this specific subgroup.

[Anxiety disorders and unexplained syncopes of presumed vaso-vagal origin]

The impact of anxiety neurosis on the diagnosis and treatment of patients with unexplained syncope (S) was assessed in 178 patients (91 women and 87 men) with an average age of 36.5 +/- 20 years, presenting with 10.7 +/- 24 episodes of S). None had evidence of underlying cardiac disease apart from 7 patients with mild hypertension. All patients underwent a tilt test (TT) at 60 degrees for 45 minutes. A bolus of isoproterenol was injected intravenously in subjects with negative TT. After the test, the patients were classified according to the presence (n = 38) or absence (n = 140) of anxiety neurosis based on the DSM III-R diagnostic. The TT was positive in 76 patients, 9 of whom had a cardioinhibitory reaction with prolonged asystole. Patients with anxiety had more episodes of S (24 +/- 43 versus 7 +/- 13; p = 0.001), a shorter interval between S (11.5 +/- 23 months versus 12.5 +/- 20 months, p = 0.02) but more negative TT (27/38 versus 75/140; p = 0.05). One hundred and sixty-eight patients were followed up : 10 were lost to follow-up. Preventive treatment was undertaken in 59 patients who were representative of the whole group with respect to age (30 +/- 18 years 39 +/- 21 years : p = 0.004). After an average follow-up of 24.5 +/- 15 months, 26 patients (15%) experienced a recurrence of S. The recurrence rate was identical in patients with positive and negative TT and in treated and untreated cases. On the other hand, recurrence was higher in those with anxiety (12/25 versus 14/117; p = 0.001) who also had less improvement of symptoms (12/15 versus 74/120; p = 0.001). The "anxiety" variable was therefore identified as being the only predictive factor for recurrence of syncope. The authors conclude that in patients referred for investigation of unexplained syncope, some suffer from anxiety neurosis, in whom the TT is usually negative, and have a higher risk of recurrence. They justify a specific therapeutic management.