Aminoglycoside-induced sensorineural hearing loss in pediatric cystic fibrosis patients: A retrospective cohort study

Background

Pulmonary infections by gram-negative organisms are important in cystic fibrosis (CF). Aminoglycosides (AG) are often part of the treatment regimen. However, they are a well-known cause of ototoxicity. Even minimal hearing impairment in children could have a future impact on functional well-being.We aimed to investigate the progression of sensorineural hearing loss (SNHL) over several years in pediatric CF patients, and to identify risk factors, such as the use of AG, including both intravenous (IV) and inhaled AG.

Methods

Retrospective analyses of patient records from children and adolescents followed up at the CF clinic of the Antwerp University Hospital, Belgium, were performed. We collected data on age, sex, pure-tone audiometry, and the use of AG. Descriptive and binary logistic regression analyses, and if indicated generalized estimating equations (GEE) analyses were performed.

Results

Forty pediatric patients were enrolled in the study taking part from 2013 to 2020. Pure-tone audiometry revealed an important rate of SNHL over several years, with a prevalence of 29 % for high-frequency SNHL (i.e. 8 kHz). Increasing age was identified as a significant risk factor for the development of SNHL at 8 kHz if 5 or more IV AG courses (p = 0.01) were reported or when IV AG were combined with inhaled AG (p = 0.002).

Conclusions

Age combined with the use of IV AG (≥5 courses or in combination with inhaled AG) are predictive for developing high-frequency SNHL (i.e. 8 kHz). We suggest routine annual hearing screening (incl. high-frequency thresholds) in CF patients, starting from childhood.

Polymyxin B complexation enhances the antimicrobial potential of graphene oxide

Introduction

The antibacterial activity of graphene oxide (GO) has been widely explored and tested against various pathogenic bacterial strains. Although antimicrobial activity of GO against planktonic bacterial cells was demonstrated, its bacteriostatic and bactericidal effect alone is not sufficient to damage sedentary and well protected bacterial cells inside biofilms. Thus, to be utilized as an effective antibacterial agent, it is necessary to improve the antibacterial activity of GO either by integration with other nanomaterials or by attachment of antimicrobial agents. In this study, antimicrobial peptide polymyxin B (PMB) was adsorbed onto the surface of pristine GO and GO functionalized with triethylene glycol.

Methods

The antibacterial effects of the resulting materials were examined by evaluating minimum inhibitory concentration, minimum bactericidal concentration, time kill assay, live/dead viability staining and scanning electron microscopy.

Results and discussion

PMB adsorption significantly enhanced the bacteriostatic and bactericidal activity of GO against both planktonic cells and bacterial cells in biofilms. Furthermore, the coatings of PMB-adsorbed GO applied to catheter tubes strongly mitigated biofilm formation, by preventing bacterial adhesion and killing the bacterial cells that managed to attach. The presented results suggest that antibacterial peptide absorption can significantly enhance the antibacterial activity of GO and the resulting material can be effectively used not only against planktonic bacteria but also against infectious biofilms.

Correction to "Bonding of Neuropeptide Y on Graphene Oxide for Drug Delivery Applications to the Central Nervous System"

[This corrects the article DOI: 10.1021/acsanm.2c03409.].

Mechanisms of Radical Formation on Chemically Modified Graphene Oxide under Near Infrared Irradiation

In this work, the mechanisms of radical generation on different functionalized graphene oxide (GO) conjugates under near-infrared (NIR) light irradiation are investigated. The GO conjugates are designed to understand how chemical functionalization can influence the generation of radicals. Both pristine and functionalized GO are irradiated by a NIR laser, and the production of different reactive oxygen species (ROS) is investigated using fluorimetry and electron paramagnetic resonance to describe the type of radicals present on the surface of GO. The mechanism of ROS formation involves a charge transfer from the material to the oxygen present in the media, via the production of superoxide and singlet oxygen. Cytotoxicity and effects of ROS generation are then evaluated using breast cancer cells, evidencing a concentration dependent cell death associated to the heat and ROS. The study provides new hints to understand the photogeneration of radicals on the surface of GO upon near infrared irradiation, as well as, to assess the impact on these radicals in the context of a combined drug delivery system and phototherapeutic approach. These discoveries open the way for a better control of phototherapy-based treatments employing graphene-based materials.

Effects of industrially produced 2-dimensional molybdenum disulfide materials in primary human basophils

MoS₂ has been increasingly used in place of graphene as a flexible and multifunctional 2D material in many biomedical applications such as cancer detection and drug delivery, which makes it crucial to evaluate downstream compatibility in human immune cells. Molybdenum is a component of stainless-steel stent implants and has previously been implicated in stent hypersensitivity. In view of this, it is important to ascertain the effect of MoS₂ on allergy-relevant cells. Basophils are a less commonly used immune cell type. Unlike mast cells, basophils can be easily derived from primary human blood and can act as a sentinel for allergy. However, merely testing any one type of MoS₂ in basophils could result in different biological results. We thus decided to compare 2D MoS₂ from the two companies BeDimensional© (BD) and Biograph Solutions (BS), manufactured with two different but commonly exploited methods (BD, deoxycholate surfactant in a high-pressure liquid exfoliation, and BS using glycine in ball-milling exfoliation) to elucidate immunological end-points common to both MoS₂ and to demonstrate the need for biological verification for end-users who may require a change of supplier. We report higher histamine production in human basophils with MoS₂. No effects on either surface basophil activation markers CD63 and CD203c or reactive oxygen species (ROS) production and cell viability were observed. However, different cytokine production patterns were evidenced. IL-6 and IL-1β but not TNF and GM-CSF were increased for both MoS₂. BS-MoS₂ increased IL-4, while BD-MoS₂ decreased IL-4 and increased IL-13. Molybdate ion itself only increased IL-1β and IL-4. Deoxycholate surfactant decreased viability at 18 h and increased ROS upon basophil activation. Therefore, these results demonstrate the safety of MoS₂ in human basophils in general and highlight the importance of considering manufacturer additives and variability when selecting and investigating 2D materials such as MoS₂.

Bonding of Neuropeptide Y on Graphene Oxide for Drug Delivery Applications to the Central Nervous System

Nanoscale graphene-based materials (GBMs) enable targeting subcellular structures of the nervous system, a feature crucial for the successful engineering of alternative nanocarriers to deliver drugs and to treat neurodisorders. Among GBMs, graphene oxide (GO) nanoflakes, showing good dispersibility in water solution and being rich of functionalizable oxygen groups, are ideal core structures for carrying biological active molecules to the brain, such as the neuropeptide Y (NPY). In addition, when unconjugated, these nanomaterials have been reported to modulate neuronal function per se. Although some GBM-based nanocarriers have been tested both in vitro and in vivo, a thorough characterization of covalent binding impact on the biological properties of the carried molecule and/or of the nanomaterial is still missing. Here, a copper(I)-catalyzed alkyne-azide cycloaddition strategy was employed to synthesize the GO-NPY complex. By investigating through electrophysiology the impact of these conjugates on the activity of hippocampal neurons, we show that the covalent modification of the nanomaterial, while making GO an inert platform for the vectorized delivery, enhances the duration of NPY pharmacological activity. These findings support the future use of GO for the development of smart platforms for nervous system drug delivery.

Hard Nanomaterials in Time of Viral Pandemics

The SARS-Cov-2 pandemic has spread worldwide during 2020, setting up an uncertain start of this decade. The measures to contain infection taken by many governments have been extremely severe by imposing home lockdown and industrial production shutdown, making this the biggest crisis since the second world war. Additionally, the continuous colonization of wild natural lands may touch unknown virus reservoirs, causing the spread of epidemics. Apart from SARS-Cov-2, the recent history has seen the spread of several viral pandemics such as H2N2 and H3N3 flu, HIV, and SARS, while MERS and Ebola viruses are considered still in a prepandemic phase. Hard nanomaterials (HNMs) have been recently used as antimicrobial agents, potentially being next-generation drugs to fight viral infections. HNMs can block infection at early (disinfection, entrance inhibition) and middle (inside the host cells) stages and are also able to mitigate the immune response. This review is focused on the application of HNMs as antiviral agents. In particular, mechanisms of actions, biological outputs, and limitations for each HNM will be systematically presented and analyzed from a material chemistry point-of-view. The antiviral activity will be discussed in the context of the different pandemic viruses. We acknowledge that HNM antiviral research is still at its early stage, however, we believe that this field will rapidly blossom in the next period.

P1266 Infectious endocarditis- still a diagnostic dilemma

INTRODUCTION

Infectious endocarditis is still a challenge with a high mortality and complication rate despite the progress made in its management.

DESCRIPTION OF CLINICAL CASE

A 58 years old female, with a history of mitral and aortic mechanical prosthesis for rheumatic valvular disease and mitral infectious endocarditis with Aggregatibacter Actinomycetemcomita due to an apical abscess was referred to our service for persistent fever.

The clinical examination revealed irregular mechanical prosthesis beats, with no heart murmurs and no signs of heart failure, but with a tender splenomegaly.

The laboratory tests showed an inflammatory syndrome, but no positive blood cultures. An extensive panel for endocarditis was negative for Coxiella burnetii, Brucella Spp, Legionella Spp, Mycoplasma Spp and for the immunology markers (rheumatoid factor, antinuclear antibodies and anti-cardiolipin antibodies)

ECG

AF, 88 bpm, PVC bigeminy, LBBB.

Infectious endocarditis was the most likely diagnosis considering the fever, the inflammatory syndrome, the presence of the mechanical valves and the history of endocarditis.

An echocardiography was performed that showed a non-dilated left ventricle with a preserved EF, no aortic prosthesis dysfunction, nor mitral; a dilated RV with normal function, moderate tricuspid regurgitation, no intracardiac masses and no pericardial effusion.

The TEE revealed no vegetation, no abscess or pseudoaneurysms and no dehiscence of the prosthetic valves.

The Endocarditis Team was reunited and empirical antimicrobial therapies with Amoxiciline, Gentamicine and Cloxaciline for 6 weeks, as well as a PET scan were recommended.

The PET-CT revealed abnormal fixation in the posterior-inferior part of the aortic valve.

As we had only one major criterion and two minor criteria for the diagnosis of endocarditis a radiolabeled leukocytes SPECT CT that showed no pathological fixation was realised. The result was inconclusive as it was performed at the end of the antimicrobial treatment.

A computed tomography of the brain, thorax, abdomen and pelvis didn’t reveal any vascular phenomena. The tender splenomegaly was secondary to two hemangiomas.

Also a dental computed tomography revealed an apical abscess of 1.2 that was treated after discharge with antibiotic prophylaxis.

DISCUSSION

This clinical case confirms that the diagnosis on infectious endocarditis can be challenging in patients with prosthetic valves. The multimodality imaging is of major importance for the diagnosis of these patients.

Additionally the microbiological criteria was not met in this case as it was a blood culture-negative endocarditis with a history of previous antibiotic therapy.

CONCLUSION

Our knowledge of infectious endocarditis is constantly evolving. Blood culture negative endocarditis accounts for one third of cases and is still a challenge. The Endocarditis Team and multimodality imaging play a central role in the diagnosis and treatment of these patients.

Abstract P1266 Figure. PET-CT showing AV abnormal fixation

Sequential dual-site High-Definition transcranial Direct Current Stimulation (HD-tDCS) treatment in chronic subjective tinnitus: study protocol of a double-blind, randomized, placebo-controlled trial

Background

Chronic tinnitus is a highly prevalent symptom, with many patients reporting considerable effects of tinnitus on quality of life. No clear evidence-based treatment options are currently available. While counseling-based methods are valuable in some cases, they are not sufficiently effective for all tinnitus patients. Neuromodulation techniques such as high-definition transcranial direct current stimulation (HD-tDCS) are proposed to have positive effects on tinnitus severity but, to date, these effects have not been proven conclusively. The proposed trial will investigate the hypothesis that chronic tinnitus patients receiving HD-tDCS will report a positive effect on the impact of tinnitus on daily life, as compared to patients receiving sham stimulation.

Methods

This study proposes a randomized, double-blind, placebo-controlled trial with parallel group design. A total of 100 chronic tinnitus patients will be randomly allocated to an experimental group or a sham group, with allocation stratified according to gender and tinnitus severity. Patient and researcher will be blinded to the patient’s allocation. Patients will undergo six sessions of sequential dual-site HD-tDCS of the left temporal area and the right dorsolateral prefrontal cortex. Evaluations will take place at baseline, immediately following treatment, and at three and six months after the start of the therapy. The primary outcome measure is the change in Tinnitus Functional Index (TFI) score. Secondary outcome measures include audiological measurements, cortical auditory evoked potentials, the Repeatable Battery for the Assessment of Neuropsychological Status adjusted for hearing-impaired individuals (RBANS-H), and supplementary questionnaires probing tinnitus severity and additional symptoms. By use of a linear regression model, the effects of HD-tDCS compared to sham stimulation will be assessed.

Discussion

The objective of this study is to evaluate whether HD-tDCS can reduce the impact of tinnitus on daily life in chronic tinnitus patients. To date, published trials on the effects of HD-tDCS on tinnitus suffer from a lack of standardization and few randomized controlled trials exist. The proposed study will be the first adequately powered trial to investigate the effects of sequential dual-site HD-tDCS on tinnitus severity.

Trial registration

ClinicalTrials.gov, NCT03754127. Registered on 22 November 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3594-y) contains supplementary material, which is available to authorized users.

Predictive factors of speech understanding in adults with cochlear implants

OBJECTIVE

The aim of this study was to analyse the factors that influenced speech recognition scores in quiet conditions and speech reception threshold levels (SRT) in fixed noise conditions, after cochlear implant (CI) surgery in adults with postlinguistic deafness.

STUDY DESIGN

Combined retrospective and prospective study in a tertiary referral centre.

METHODS

We included 66 patients that received implants between 2002 and 2013. We retrospectively collected speech recognition scores and 14 demographic, audiological, and technical factors, including gender, age at implantation, aetiology, hearing loss progression, preoperative Pure Tone Average (PTA), hearing loss onset age and duration, duration and use of hearing aids (HAs); implantation in the best or worst ear; implantation on the right or left side; use of HA after implantation; and the duration and type of CI. We prospectively tested a subgroup of 21 patients for SRT in fixed noise.

RESULTS

The hearing loss duration significantly affected speech recognition scores in quiet conditions (H (4) = 10.567, p =0.032) and SRTs in fixed noise conditions (rs = 0.466, p = 0.033). The PTA of the better ear significantly affected only the SRT in fixed noise conditions (rs = 0.57 1, p = 0.007).

CONCLUSION

The duration of hearing loss and the PTA of the best ear had significant effects on the outcomes of speech recognition and SRT in quiet and fixed noise conditions, respectively. These findings are important for counselling CI candidates. Further studies in larger study populations are warranted.

[Prehospital treatment with bivalirudin in acute myocardial infarction referred for primary angioplasty. About 152 consecutive patients study]

OBJECTIVE OF THE STUDY

Bivalirudin, a direct thrombin inhibitor, demonstrated an improvement in the prognosis of acute coronary syndromes by a decrease in major bleeding complications. This observational study evaluated inhospital outcome of patients with acute myocardial infarction treated by prehospital bivalirudin before primary angioplasty.

PATIENTS AND METHODS

We included, from June 2010 to June 2012, all patients with acute myocardial infarction receiving prehospital bivalirudin with bolus of 0.75mg/kg followed by an infusion of 1.75mg/kg per hour until the arrival in the catheterization laboratory. Bivalirudin was possibly continued after primary angioplasty.

RESULTS

We included 152 patients aged 57.6±11.6 years. A prehospital 60mg loading dose of prasugrel was given in 77% of patients. Coronary angiography with radial access (77.6%) was performed before a successful angioplasty in 97.3% of cases. The bivalirudin infusion was continued after the procedure in 81.6% of patients. Inhospital outcome showed two deaths (1.3%) and two re-infarctions (1.3%) of which one was related to the single acute stent thrombosis (0.6%). Major bleeding complications were limited irrespective of the Gusto (0.6%), Timi (0.6%) or Horizons-MI (4.6%) classification. Bleeding complications rate was similar when bivalirudin was followed or not after primary angioplasty.

CONCLUSION

The use of bivalirudin in the prehospital setting for primary angioplasty seems to be effective and safe about ischemic and bleeding complications during the inhospital outcome.

Incomplete bundle-branch block and ST-segment elevation: syndrome associated with sustained monomorphic ventricular tachycardia in patients with apparently normal heart

This paper reports on three cases of patients with an apparently normal heart admitted for sustained monomorphic ventricular tachycardia. The only abnormal finding showed in the electrocardiogram (ECG) in sinus rhythm that exhibited an entity associated with incomplete right bundle-branch block and persistent ST-segment elevation. The ECG entity was variable and disappeared transiently. Spontaneous ventricular tachycardia in one patient was inducible by programmed stimulation. There was no underlying heart disease. The origin of the ventricular tachycardia in one patient was located by pace mapping in the left ventricle at the left ventricular basal septum. The follow-up (from 6 months up to 6 years) demonstrated a good prognosis. This particular ECG entity associated with monomorphic ventricular tachycardia could have been missed because of the variations in the ECG in sinus rhythm and was associated with a favorable prognosis.

[Non ST elevation acute coronary syndromes and normal coronary angiography: is it truly good news?]

Among 10% of all patients presenting with non ST elevation acute coronary syndromes (ACS), coronary angiography do not show non lesions at all (50%) or mild atheromatous stenosis (50%). ACS without angiographic stenosis are more prevalent in female sex and young patients but can be seen in older ones and in men. Pathogenic mechanisms include acute evolution of vulnerable non-significant plaques and endothelial dysfunction. In hospital and mean term prognosis is not as benign as expected. Six months deaths and myocardial infarction incidence is around 6%. Numerous rehospitalizations due to ischemic recurrences are also very often seen. Therefore, such surprising coronary angiograms do not preclude a fair follow-up. These patients need a careful therapeutic strategy.

[Acute myocardial infarction with cardiogenic shock following stress echocardiography: case report]

Acute myocardial infarction is a rare complication of dobutamine stress echocardiography (DSE). We report the case of a 60-year-old man with moderate apical sequela of a myocardial infarction (MI) which had an inferior MI complicated with cardiogenic shock and circulatory arrest two hours after a positive DSE in that very circulatory topography. Emergency coronarography objectivizes a dissection of the circumflex artery. The patient required a circulatory assistance device. He survived the episode and left the hospital with 50% left ventricular ejection fraction.

[Acute myocardial infarction in octogenarians treated by primary coronary angioplasty: in hospital outcome, social evolution and long-term mortality. About a forty-seven consecutive patients study]

This study evaluated the hospital outcome of octogenarian patients treated by primary angioplasty for acute myocardial infarction less than 12 hours. The long-term mortality and social outcome were evaluated, social outcome was based on IADL and IADL-E scales corresponding to physical autonomy and level of dependence. We included from 1999 to 2005 47 old patients of 83.5+/-3.2 years. The reperfusion of the obstructed coronary artery was obtained in 45 patients (95.7%) with TIMI 3 flow. Hospital mortality was 25.5% and 4.2% without hemodynamic complication. A multivariate analysis identified a Killip score>1 as predictive factor of hospital mortality (OR=8.9 and p=0.05). The long-term survival without death with a follow-up of 26.3+/-18.3 months was 82.2% at 24 months and 70.6% at 48 months according to the Kaplan-Meier method. In an multivariate analysis, hospitalization exit without aspirine was associated with a higher long term mortality (OR=34.8 and p=0.04). According to the evolution of scores of IADL and IADL-E scales, patients had an excellent autonomy and good capacities before the infarction and they kept them on the long term. Thus octogenarians with acute myocardial infarction treated by primary angioplasty have a high in hospital and long term mortality but the survivors preserve an excellent daily autonomy.

[Primary angioplasty in acute coronary syndromes with ST-segment elevation: experience of three Alsacian centers]

The guidelines of the European Society of Cardiology, published in 2003, consider primary angioplasty as the preferred treatment strategy in acute coronary syndromes with ST-segment elevation, if the procedure can be performed within 90 min after first medical contact. We report the experience of three Alsacian centers running a common prospective registry with 2504 consecutive patients enroled between January 1999 and December 2004. The average age of the patients was 62 years with a proportion of 24% women. The time delay "pain to admission" was > or =3 hours in 55.9% of the cases. The treatment delay "door to catheterisation needle" was 59 min and the mean delay "door-to-reperfusion" was 79 min. The study population was representative of the real world including subsets of patients with a particulary high risk profile: age > or =70 years in 33%, a Killip grade > or =3 in 11.5%, rescucitated sudden death in 6.6% and cardiogenic shock in 10.9% of the patients respectively. The immediate procedural success rate (Timi 3 flow) in the treated coronary artery was 96.5%. The overall inhospital mortality-rate was 9.3%. The combinations of rescucitated sudden death--cardiogenic shock or age > or =75 years--cardiogenic shock were associated with a poor clinical outcome and mortality rates of 69% and 72.6% respectively, where as in the absence of abovementioned clinical high risk settings, the mortality rate was as low as 1.4%. The overall bleeding complication rate was 1.4%. The policy of systematic primary angioplasty in acute coronary syndromes with ST-Segment elevation appears to be coherent. The procedural complications and the in-hospital mortality rates were low, except in the presence of above mentioned clinical high risk settings.

Infarctus du myocarde du sujet de plus de 75 ans

OBJECTIVES

This prospective multicenter study assessed the prevalence and feasibility of percutaneous coronary angioplasty (PTCA) in the acute phase of ST-elevation myocardial infarction (STEMI) in 3 nonacademic interventional cardiology centers (Alsace, France).

METHODS

We studied the clinical characteristics, angiographic data, and PCTA results of all STEMI patients and analyzed the revascularization rates and adverse events during hospitalization. We compared patients at least 75 years of age and younger patients for these data and with the literature.

RESULTS

Of the 1672 patients admitted for STEMI, 342 (20.45%) were at least 75 years of age. Half the patients in this high-risk subgroup were women. These patients had more co-morbidities (e.g., hypertension and diabetes mellitus) than younger patients, and more of them had three-vessel disease. Mortality rate was high in this subgroup and always higher than for comparable younger subjects, but it varied according to the initial clinical profile. Their global mortality rate was 20.47%, but it fell to 5.41% when we excluded patients with cardiogenic shock or in Killip stage ill, and those who were resuscitated. PTCA is a coronary reperfusion technique especially indicated for elderly patients with STEMI. It is an effective revascularization technique, with a reperfusion rate (exclusively TIMI III flow) reaching 93.88% in the elderly group, only slightly lower than among younger patients (97.18%).

CONCLUSION

PTCA is a technique particularly indicated in the elderly in Alsace because of regional geographic and medical specificities: nearby emergency services are available to virtually the entire population of Alsace, and most interventional cardiology teams apply a strategy of exclusive primary PTCA.

[Late stent-thrombosis-related myocardial infarction]

The objective of the study was to assess the frequency of late stent-thrombosis-related acute myocardial infarction in patients with LAD stents. A series of 930 PCI procedures involving LAD stenting were performed in 920 patients (mean age: 63 years, 667 men) from January 1999 to December 2001. Among those 14 patients had late (> 30 days), thrombosis-related acute myocardial infarction after a mean delay of 135 +/- 131 days. Three-year thrombosis-free survival was 97.6%. By univariate analysis, risk of late thrombosis was associated with LAD-diagonal bifurcation stenting, placement of a stent on the ostium of a diagonal branch and number of stents implanted on the LAD. Patients with these risk factors might be appropriate candidates for long-term combined antiplatelet therapy.

[Acute STEMI in old and very old patients. The real life]

OBJECTIVES

From a prospective multicenter registry, we evaluated in three non-academic interventional cardiologic centers (Alsace/France), the coverage and the feasibility of the percutaneous coronary angioplasty (PTCA) in the acute phase of STEMI in the elderly (patients 75-years old and more).

METHODS

We studied clinical characteristics and angiographic data of patients older than 75 years, and the PTCA results: the revascularisation rates and the intrahospital events were analysed. These data were compared with those of the younger patients and confronted with the literature data.

RESULTS

Of a total of 1672 patients admitted for a STEMI, 342 (20.45%) were older than 75 years. These patients represented a high-risk group with a high proportion of women (50%), and many co-morbidities (e.g.: hypertension and diabetes mellitus), and three-vessel disease was found more often than in younger patients. Mortality rate was high in this subgroup and always more severe as compared to younger subjects, but remains variable according to the initial clinical profile. The global mortality was 20.47% but fell to 5.41% if we excluded the patients with cardiogenic shock, in Killip III and after resuscitation. PTCA is a coronary reperfusion technique particularly indicated in the management of the elderly presenting a STEMI. It is an effective technique in term of revascularisation, the reperfusion success (exclusively TIMI III flow) was indeed raised in the elderly even though it is lower than in younger patients (93.88 vs 97.18%). It is a quickly accessible technique, cath-lab accessibility provided, allowing a fast reperfusion and reducing hospitalization to a minimum. The management of the elderly presenting a STEMI has to focus on reducing the preadmission delay since this subgroup of patients hesitates to call the emergency (SMUR) when presenting an acute coronary symptomatology. The shorter the delay till admittance, the better the outcome.

CONCLUSION

PTCA is a technique particularly indicated in the elderly in Alsace because of regional specificities: first of all geographic (proximity of the SMUR for virtually all the population of Alsace), and secondly the medical infrastructure since the strategy of exclusive primary PTCA is granted by numerous interventional cardiologic teams. In Alsace, the proportion of elderly patients (> or = 75 years) is going to increase significantly with a parallel rise of STEMI--"a frightening perspective". We have to take into account this evolution, this reperfusion technique presenting numerous advantages and very few complications.

[Primary cardiogenic shock in the acute phase of myocardial infarction treated by angioplasty: experience of three non-university public centers in Alsace]

OBJECTIVE AND METHOD

Evaluation of angioplasty for primary cardiogenic shock in acute myocardial infarction in three non-universitary alsacians centres between 1999 and 2002.

RESULTS

One hundred and eighty-two patients were included. Hospitalisation survival rate is 43.96% after hospital discharge. One hundred and forty-nine patients were treated by primary angioplasty. Angioplasty is successful in 79.12%. The predictives factors of death are: age > 75, TIMI = 0 at the admission, three vessels disease. Twenty-four months survival is 91% (follow-up data available on 28.75% of the patients alive at hospital discharge).

CONCLUSION

Angioplasty seems to be the right choice in case of acute myocardial infarction complicated by cardiogenic shock, the results are better than medical treatment at short- and mid-term.

Genomic studies in AIDS: problems and answers. Development of a statistical model integrating both longitudinal cohort studies and transversal observations of extreme cases

Genomic studies developed to understand HIV-1 infection and pathogenesis have often lead to conflicting results. This is linked to various factors, including differences in cohort design and selection, the numbers of patients involved, the influence of population substructure, the ethnic origins of the participants, and phenotypic definition. These difficulties in the interpretation of results are examined through published studies on the role of polymorphisms in HLA and the chemokine receptors genes in AIDS. Our analysis suggests that the use of haplotypes will strengthen the results obtained in a given cohort, and meta-analysis including multiple cohorts to gather large-enough numbers of patients should also allow clarification of the genetic associations observed. A P-value of 0.001 appears to be a good compromise for significance on candidate genes in a genetic study. Due to the generally limited size of available cohorts, results will have to be validated in other cohorts. We developed a model to fit transversal case studies (extreme case-control studies) with longitudinal cohorts (all-stages patients) for observations on two gene polymorphisms of CCR5 and NQO1. Interestingly, we observe a protective effect for the CCR5-Delta32 mutant allele in 95% of the simulations based on that model when using a population of 600 subjects; however, when using populations of 250 subjects we find a significant protection in only 59% of the simulations. Our model gives thus an explanation for the discrepancies observed in the various genomic studies published in AIDS on CCR5-Delta32 and other gene polymorphisms: they result from statistical fluctuations due to a lack of power. The sizes of most seroconverter cohorts presently available seem thus insufficient since they include less than a few hundred subjects. This result underlines the power and usefulness of the transversal studies involving extreme patients and their complementarity to longitudinal studies involving seroconverter cohorts. The transposition approach of extreme case-control data into longitudinal analysis should prove useful not only in AIDS but also in other diseases induced by chronic exposure to a foreign agent or with chronic clinical manifestations.

[Off-pump beating heart coronary artery bypass. Technical points of view and surgical results]

A consecutive series of 746 patients undergoing heart beating myocardial revascularization was reviewed. An average of 2.30 grafts/patients was performed. The rate of mortality in the first 30 postoperative days was 0.28%. Two cases had to be terminated on-pump. We used the inotropic drugs in 0.6% of cases. The postoperative events were: atrial fibrillation (12.6%), myocardial infarction (0.3%). The rate of transfusion was 7.4%. The extubation was performed in the first 24 h postoperatively in 94.7% of cases. The majority of patients (91.3%) left the hospital in the first 8 d postoperatively. Off pump coronary artery bypass grafting gives good result for the most of the patients even for those with multiple vessel disease and high operating risk.

[Incidence and prognosis of atrioventricular block induced by radiofrequency ablation of intranodal reentrant tachycardia. A multicenter study]

The object of this study was to assess the incidence and significance of atrioventricular block (AVB) induced by radiofrequency ablation of intranodal reentrant tachycardias. The study population was 18 patients aged 44 to 83, selected from a total population of 144 patients treated for recurrent, refractory tachycardias. These patients developed complete AVB (9 cases), 2nd degree ABV (3 cases) and 1st degree AVB (6 cases) either immediately or in the chronic phase after radiofrequency ablation. The outcomes were as follows: 1. In the 9 patients with complete AVB, the block regressed in a period ranging from 7 seconds to 5 minutes. It recurred as complete AVB 1 to 4 days later in 2 patients, and regressed again after a maximum of 10 days. One 47 year old woman had definitive complete AVB; 2. In the 3 patients with 2nd degree AVB, the block regressed within 7 days; 3. In the 6 cases of 1st degree AVB, 2 patients developed transient complete AVB the following day. The possible causes of AVB were: increased vagal tone in 1 case, ablation of the rapid pathway located in a postero-septal site in 8 cases and, in the remainder, pre-existing conduction defects. The authors conclude that transient complete AVB is common and usually has a good prognosis. Definitive complete AVB is a rare but possible (0.7%) complication of radiofrequency ablation of reentrant intranodal tachycardias; other forms of AVB generally regress quickly and, although they may recur within days, they carry a good prognosis in the following months. However, long-term follow-up remains necessary.

[Curative radiofrequency ablation of paroxysmal junctional tachycardia in patients over 70 years of age. A multicenter study]

Curative radiofrequency ablation of the reentry circuit of paroxysmal junctional tachycardia is a relatively common method of treating this condition. The aim of this study was to determine whether the age of the patients should be taken into account for assessing the indication. The study population was 178 patients aged 18 to 86 years (average 56 +/- 19 years), who had paroxysmal junctional tachycardia and normal interatrial ECGs. One hundred and thirty-five patients were under 70 years of age (Group I) and 43 were over 70 (Group II). No significant differences in the mechanism of reentry, which was intranodal in 67% of cases, in the risk of immediate complications (11%) or in recurrence of tachycardia were observed between the two groups. Functional improvement was more spectacular in Group II with regression of the symptoms of associated cardiac disease and, above all, in reduction in the number of hospital admissions. The common association of cardiac disease and other pathologies in Group II should however lead to more careful management and follow-up of the more elderly patients. The authors conclude that radiofrequency ablation of paroxysmal junctional tachycardia in the over 70s is feasible and often provides better clinical results than observed in younger patients.

[Angioplasty or surgery in the patient with multivessel disease]

The aims of myocardial revascularisation are to treat angina, reduce ischaemia and improve life expectancy. Patients with multivessel disease have a poor prognosis, especially when the lesions are proximal, when the preseptal left anterior descending artery is involved and when left ventricular dysfunction is present. In this particular group of patients, coronary bypass surgery has been shown to improve 10 year survival. Coronary angioplasty has been compared with surgical treatment in many clinical trials. The medium-term survival is the same in both groups, but with a higher number of repeat procedures except in diabetic patients in whom mortality is higher after angioplasty. The use of coronary stents should reduce the number of post-angioplasty procedures. Constant technical improvements, the introduction of surgery without cardiopulmonary bypass, combined revascularisation procedures, new antiplatelet drugs, the absence of long-term comparative results, all this results in a personalized choice of revascularisation procedure based on the overall clinical and angiography features of each particular case.

[Long-term follow up of 115 patients with ischemic heart disease and ventricular flutter induced by programmed ventricular stimulation in the absence of ventricular arrhythmia]

The clinical significance of rapid monomorphic ventricular tachycardia (VT) (> 270 beats/min), also called ventricular flutter, remains controversial in patients without documented spontaneous sustained VT. The aim of this study was to evaluate the outcome of 115 patients with ischaemic heart disease, aged 58 +/- 10 years, without spontaneous ventricular arrhythmias, but who had inducible ventricular flutter during programmed ventricular stimulation. The patients underwent stimulation to evaluate the prognosis after myocardial infarction or to investigate a malaise with or without loss of consciousness. Sustained ventricular flutter was the only inducible arrhythmia in all patients. The mean left ventricular ejection fraction (LVEF) was 42 +/- 14%. During an average follow-up period of 66 +/- 43 months, 31 deaths, including 27 of cardiac causes, were observed. The 1, 5, and 11 year survival of the whole population was 94, 79 and 64% respectively. In univariate analysis, anterior wall myocardial infarction, a low LVEF, the presence of non-sustained ventricular tachycardia (NSVT) on 24 hour Holter monitoring and Class III antiarrhythmic treatment, were poor prognostic factors (p 0.05). In multivariate analysis, the only independent predictive factors of mortality were low LVEF (p = 0.006), the presence of NSVT on Holter monitoring (p = 0.003) and the absence of betablocker therapy (p = 0.015). Medical therapy with betablockers or the implantation of an automatic defibrillator may be indicated in these patients at higher risk.

Increased atrial vulnerability in arrhythmogenic right ventricular disease

Supraventricular tachyarrhythmias (SVTA) may occur in patients with the arrhythmogenic right ventricular dysplasia (ARVD). The purpose of the study was to evaluate the incidence of SVTA in 47 patients with ARVD proved by right ventricular angiography. Thirty-three men and 14 women, aged 21 to 72 years (mean 44 +/- 18) were admitted for nonsustained or sustained ventricular tachycardia. Eight patients had a history of spontaneous SVTA several years before ventricular tachycardia occurrence. Protocol of the study consisted of programmed atrial stimulation with one and two extrastimuli delivered during sinus rhythm and two driven rhythms (600 and 400 msec), programmed ventricular stimulation with up to three extrastimuli and was performed in the control state and after infusion of isoproterenol. The results of programmed atrial stimulation were compared with those obtained in 36 asymptomatic subjects without heart disease and with a mean age of 50 +/- 18 years (control group). Sustained SVTA (> 1 minute) was induced in seven of eight patients with spontaneous SVTA, in 27 (69%) of those with ARVD, who did not have spontaneous SVTA, and in two control subjects (5.5%) (p < 0.001). SVTA was inducible in the control state, but ventricular tachycardia induction required isoproterenol in 11 of 27 patients. Two patients without SVTA history but with inducible SVTA developed later spontaneous SVTA. ARVD was associated with a significantly higher incidence of inducible SVTA than in a control population. Supraventricular tachycardias may precede ventricular tachycardias. This association argues for a diffuse myocardial disorder in ARVD.

[Evaluation of high amplification ECG and the study of sinus variability in the detection of patients at risk of sudden death]

In order to define the best strategy of prognostic evaluation in relation to patients in heart failure, 415 patients with impaired left ventricular function (ejection fraction < 40%) were prospectively included, between June 1993 and 1996, in a study comparing the respective value of high amplification ECG and Holter analysis of sinus variability, 308 patients in sinus rhythm and narrow QRS complexes were included. The patients were distributed into 4 groups according to the presence or absence of late potentials and altered sinus variability (group I with 2 normal examinations, group II with late potentials and normal variability, group III without late potentials, but with altered variability and group IV with 2 abnormal examinations). The sudden and overall mortality was significantly greater in groups III (28 and 11%) and IV (28 and 9%) than in group I (7 and 3%) and II (11 and 2%). The presence of potential was unable to identify patients at risk of ventricular tachycardia and sudden death. In another 60 patients with complete branch block, the prognosis was also correlated with the alteration of sinus variability. In conclusion, high amplification ECG correctly evaluated the prognosis of subjects in heart failure. However, analysis of sinus variability should be systematically proposed to detect subjects at high risk of mortality, whether the subject has large or narrow QRS complexes.

[Hospital results of angioplasty in multiple coronary vessel disease in 1990-1991 and 1994-1995. What conclusions should be drawn about the improvement of results with respect to the relevance of data of randomized trials comparing angioplasty and surgery]

The aim of this study was to determine whether advances in angioplasty techniques have improved results in multiple vessel coronary disease and to compare present results with those reported in randomised trials comparing angioplasty and surgery. The hospital results of two cohorts of multivessel coronary patients treated by angioplasty during two different periods were compared (group 1: 1990-1991. group 2: 1994-1995). The first period corresponded to the inclusion period of randomised trials comparing surgery and angioplasty. The patients in group 2 (n = 449) were older than those in group 1 (n = 424), had more triple vessel disease, more severe angina and more previous angioplasty attempts. Moreover, there were more cases of unfavourable lesions. Nevertheless, the clinical success rate was high in group 2 (92% vs 84%; p < 0.001) and the major complication rate (death, myocardial infarction or emergency bypass surgery) was lower (2.9% vs 6.1%; p = 0.02). The main technical difference between the two periods concerned the use of coronary stents (12% vs 8%; p < 0.001). The fact of being in group 2 was identified by multivariate analysis as an independent predictor for clinical success and a lower major complication rate. The authors conclude that, since the publication of randomised trials comparing angioplasty with coronary surgery, the hospital results of angioplasty have significantly improved. This should be taken into account in considering the clinical applications of the results of these trials.

[Betablocker therapy in acute myocardial infarction]

A review of the results of randomised trials of the use of betablockers in acute myocardial infarction shows by techniques of meta-analysis that their prescription in the early hours of the acute event leads to a reduction in short-term mortality: the reduction of risk is 12% as compared with groups which are not given betablockers. In addition to its impact on mortality, early betablocker therapy is associated with a reduction in the risk of recurrence of myocardial infarction and a proven antalgic effect. However, in patients receiving thrombolysis, the beneficial effect on mortality and recurrence of infarction of intravenous betablockers seems less evident. In daily clinical practice, the prescription of betablockers in the first days of infarction has significantly increased over the last ten years. In the USIK trial carried out in France in November 1995, nearly two thirds of patients received betablocker therapy. In the same study, the prescription of betablockers is associated with a reduction in mortality independent of the classical risk factors and the prescription of angiotensin converting enzyme inhibitors. These results confirm the value of this therapeutic class in the acute phase of myocardial infarction.

[Alteration of sinus variability after cardiac surgery]

Sinus tachycardia is frequent after cardiac surgery and this tachycardia is probably due to changes of the autonomic nervous system. The objective of this study was to evaluate the changes possibly induced by cardiac surgery, by studying sinus variability (SV) during a 24-hour Holter monitoring. The examination was performed in 28 patients who had undergone cardiac surgery 1 to 6 weeks previously. These patients had no alteration of left ventricular function, or any causes likely to modify SV and they had a normal postoperative course. Their results were compared to those of 4 subjects developing a postoperative complication (1 case of ventricular tachycardia and 3 cases of resuscitated cardiac arrest). The results were also compared to those of 24 age-matched adult controls without heart disease (control group). The study of SV included temporal and spectral analysis of SV with measurement of the standard deviation of normal RR intervals (SD), mean heart rate (HR), percentage of RR intervals differing by more than 50 m/sec from the adjacent interval (pNN50), coefficient of variability (CV) (SD/RR), square root of the differences between successive RR (rMSSD), spectral properties of low frequencies (LF) and high frequencies (HF) and the fractionated spectral property (LF/HF).

RESULTS

(see tables, page 151 and 152). An alteration of SV was therefore observed in the surgical group, and lasted 4 to 6 months after surgery. No difference was observed between subjects without cardiac events and those presenting a cardiac event.

IN CONCLUSION

cardiac surgery decreases all parameters of SV during the first few postoperative months. Certain unexpected cardiac accidents during this period could be explained by these changes.

[Influence of time (4 years) on the results of programmed ventricular stimulation]

The reproducibility of programmed ventricular stimulation has been previously demonstrated for periods of a few hours to several months. It has not been studied over longer intervals. The aim of this study was to assess the reproducibility of the method at long-term (> 2 years). Forty-six patients with underlying cardiac disease underwent two programmed ventricular stimulations in the absence of antiarrhythmic treatment at intervals of 2 to 6 years (mean 4 years). None of the patients had myocardial infarction or cardiac surgery during this period. The protocol was identical: up to 3 extra-stimuli were delivered in the two right ventricular sites over 3 cycles. Twenty-eight patients had inducible sustained monomorphic ventricular tachycardia during the first investigation (Group I): the investigation was negative in the remaining 18 patients (Group II). During the second investigation, 26 of the 28 patients in Group I had inducible ventricular tachycardia, the rate of which decreased from 206 +/- 50 bpm to 196 +/- 54 bpm. The induced ventricular tachycardia was slower in 15 patients and faster in 5 patients. The mode of induction was different in 12 cases. In Group II, 4 patients (22%) had inducible sustained ventricular tachycardia at the second investigation. The authors conclude that the reproducibility of programmed ventricular stimulation remains good in the long-term in subjects within inducible tachycardia, demonstrating the stability of the arrhythmogenic substrate; the frequency of this tachycardia is generally slower. In subjects with an abnormal initial investigation who became symptomatic, it may be useful to repeat programmed ventricular stimulation.

[Reproducibility of heart rate variability in the chronic phase of myocardial infarction]

Evaluation of heart rate variability is a common method of assessing autonomic nervous system function and its effects on heart rate in different conditions. The reproducibility of the technique is not known in the chronic phase of myocardial infarction. The aim of this study was therefore to assess the reproducibility of the measurement in 54 subjects who were clinically stable with no change in treatment at a distance from acute or semi-recent (> 2 years) myocardial infarction, after an interval of one month. The temporal and spectral analysis of heart rate variability included measurement of the standard deviation of the normal RR intervals (SDNN), on the mean heart rate, the percentage of RR intervals greater than 50 ms than the adjacent interval (pNN50), the coefficient of variability (CV), the square root of the differences between successive RR intervals (rMSSD), the power of low frequencies (LF) and high frequencies (HF) and of the fractional spectral power (LF/HF). No significant changes in these parameters were observed. Analysis of individual variations showed that the heart rate was the most stable parameter: for evaluation of vagal tone, the rMSSD showed less variability than the pNN50 and HF. The presence of cardiac disease did not influence these results. The authors conclude that parameters of evaluation of heart rate variability in temporal and spectral analysis are globally reproducible in stable subjects. However, individual values may change from one measurement to another. Nevertheless, abnormal variability is constantly observed at the second investigation and, similarly, normal variability also remains unchanged. These individual variations suggest that, for the demonstration of change in these parameters of variability with treatment, large population groups must be studied.

[Prognostic value of serial electrophysiological tests in inducible sustained ventricular tachyarrhythmias]

The authors report the results of a study evaluating serial electrophysiological tests on a series of 166 patients with inducible sustained ventricular tachyarrhythmia. The initial electrophysiological investigation was indicated because of sustained ventricular arrhythmias documented in 95 patients or suspected in 71 symptomatic patients. Serial tests allowed identification of a protective antiarrhythmic treatment (non-inducible ventricular tachycardia) in 74 responding patients (44.6%) (group R) after 1.3 +/- 0.5 therapeutic trials versus 1.8 +/- 0.8 inconclusive trials in 92 non responding patients (group NR). Multivariate analysis demonstrated the absence of any underlying ischaemic heart disease (p < 0.01) and the presence of spontaneous ventricular fibrillation (p < 0.01) as independent predictive factors of success during serial testing. A follow-up of 43 +/- 29 months was available for 151 patients (91%). kaplan-Meier survival curves showed a better long-term prognosis for group R with survival rates of 97%, 87% and 70% at 1.3 and 6 years, respectively, versus 83%, 68% and 45% for group NR. Two variables were considered on multivariate analysis to be predictive factors of survival: left ventricular ejection fraction (p < 0.001) and response to serial electrophysiological tests (p < 0.02). Therapeutic ventricular pacing therefore remains a reliable method to select patients whose prognosis is improved with antiarrhythmic treatment after induction of sustained ventricular arrhythmia.

[Analysis of heart rate variability before and at the moment of cardiac death]

The study of heart rate variability is a new means of assessing autonomic nervous system function and the risks of cardiac and sudden death in patients with advandec cardiac disease. The aim of this study was to analyse changes in heart rate variability in the hours preceding cardiac death and just before its occurrence. Seventeen subjects aged 78.5 +/- 10 years, with advanced cardiac disease responsible for a reduction of left ventricular ejection fraction below 40%, died during Holter ECG recording. Ten died of ventricular fibrillation, 5 of bradycardia and 2 of non-rhythmic causes. General analysis of heart rate variability showed a decrease in all but 1 patient, the average standard deviation of normal RR intervals in subjects in sinus rhythm being 53 +/- 14 msec and the fractioned spectral power (low frequency/high frequency power) being 1 +/- .07. The change in heart rate variability did not allow prediction of the mechanism of death: the mean heart rate only increased before death in 3 of the patients with an ischaemic component in the hours before death, the indices of vagal tone were very low in the majority of patients and, just before death, a disequilibrium between the spectral powers with a sudden increase in LF/HF ratio of 10 of the 17 patients, irrespective of the cause of death, appeared. In conclusion, a decrease in heart rate variability was observed in all cases but did not predict the mechanism of death. Just before death occurred, some patients, especially those with acute ischaemia, showed a sudden change in the indices of heart rate variability indicating a terminal vaso-sympathetic disequilibrium.

[Long-term reproducibility of programmed atrial stimulation]

Programmed atrial stimulation is a technique increasingly used to assess different pathologies but the reproducibility of the results is totally unknown. The aim of this study was to determine its reproducibility. Two electrophysiological studies were undertaken without antiarrhythmic therapy in an interval of one to three months (average 18 months) in 48 patients. The programmed atrial stimulation used 1 and 2 extrastimuli delivered in sinus rhythm and then three paced rhythms (sinus cycle -10%, 600 ms, 400 ms). Twenty-one patients had documented atrial arrhythmias (atrial fibrillation n = 13, flutter n = 3 or tachycardia n = 5) (group 1) and the 27 other patients had no spontaneous arrhythmias (group II). In group I, clinical tachycardial was reproduced in 18 patients during the initial stimulation procedure. During the second investigation, 17 remained inducible and in the 3 in whom stimulation was negative, it remained so in 2 of the cases. The reproducibility was therefore 90%. In group II, 12 patients had inducible sustained (for over 1 minute) tachycardia during the first procedure (44%) but this only remained inducible in 6 patients. In the other 15 subjects, stimulation was negative during the first procedure but 7 of them had inducible tachycardial during the second procedure. The reproducibility of the technique was therefore only of 52%. The authors conclude that the reproducibility of programmed atrial stimulation in patients with documented spontaneous paroxysmal arrhythmias is excellent. However, the reproducibility is mediocre in subjects without spontaneous arrhythmias and the induction of tachycardial in this group of patients should be interpreted with caution given the variability of the response to programmed atrial stimulation.

[Coronary angiography: 1st or 2nd-line test?]

Coronary angiography, although now performed extremely frequently, remains an invasive and expensive examination, whose place, as first-line diagnostic method, must be discussed; Its main advantage is to provide a definitive diagnosis of coronary atherosclerosis as well as simple prognostic indicators (single vessel, two-vessel or three-vessel disease; concomitant evaluation of left ventricular function by associated radiological ventriculography). However, it is unable to precisely assess the degree of coronary wall disease and, more importantly, cannot evaluate the functional repercussions of stenosis. Under these conditions, only cases in which myocardial revascularization is expected to provide a definite clinical benefit (presence of frank angina symptoms) probably justify first-line coronary angiography. In all other cases, coronary angiography is a useful examination to provide reference "mapping" of the coronary lesions, but an obvious clinical benefit for the patient cannot be expected from systematic use of this technique. In particular, in such situations, coronary angiography should not be the only element on which the decision to perform myocardial revascularization should be based: the "oculostenotic reflex" must always be avoided.

Bradycardia-induced polymorphic ventricular tachycardia after radiofrequency catheter modification of atrioventricular junction

We report the case of a 59-year-old man with a dilated nonischemic cardiomyopathy who had chronic rapid atrial fibrillation despite several therapies. Radiofrequency modification of the atrioventricular (AV) junction slowed the mean ventricular rate from 120 beats per minute (bpm) to 60 bpm. Five hours after the procedure and during the following 1 week, despite ventricular pacing at 90 bpm, the patient developed nonsustained or sustained polymorphic ventricular tachycardias. Finally, pacing at 90 bpm was successfully used in this patient. In conclusion, patients who have undergone modification of AV conduction may be at high risk of life-threatening ventricular arrhythmias in the first week following the procedure.

Prognostic significance of angina pectoris > or = 30 days before acute myocardial infarction in patients > or = 75 years of age

We compared the prognostic significance of prior angina pectoris in 151 patients > or = 75 years of age admitted for acute myocardial infarction. There was a similar in-hospital course, but the long-term outcome was poorer in patients with prior angina.

[Can 1/1 atrial flutter be foreseen by class I anti-arrhythmics?]

1/1 atrial tachycardia or "quinidine" flutter under class I antiarrhythmic drugs is a serious complication of these agents which, unfortunately, cannot be anticipated. The aim of this study was to review the cases of 11 patients who had suffered this complication of class I antiarrhythmic therapy to see if it could have been prevented. All drugs of this class were included. The 11 subjects were aged 57 to 78: 7 had no apparent underlying cardiac disease and the others had valvular (n = 1), hypertensive (n = 1) and ischaemic (n = 2) heart disease. They were treated for episodes of paroxysmal atrial fibrillation or tachycardia. In the absence of treatment, 7 patients had a short PR interval on the ECG (PR between 0.11 and 0.14 s). In the other 4, the PR interval was normal (0.16 to 0.20 s), but the P wave was widened with appearances of left atrial hypertrophy or an intra-atrial conduction defect. High amplification ECG performed in 3 patients showed continuity of atrial and ventricular depolarisation. Atrial stimulation showed excellent nodal conduction with a Wenckebach point of 200/min. The authors conclude that a short PR interval is predisposing factor to 1/1 atrial tachycardia with class I antiarrhythmics. High amplification ECG which allows identification of the end of the P wave with respect to the QRS complex could help identify subjects at risk when the P wave is widened and that, consequently, the PR interval appears to be normal.

Relationships between heart rate variability and antiarrhythmic effects of hydroquinidine

Class I antiarrhythmic drugs may increase the incidence of cardiac death, and controlled treatment is required in patients with severe ventricular arrhythmias. Electrophysiologically guided antiarrhythmic therapy remains an important method to manage patients with sustained ventricular tachycardia (VT). The purpose of the study was to evaluate the correlations between baseline heart rate variability in ambulatory electrocardiographic recordings of patients with sustained ventricular tachycardia and the response to hydroquinidine on VT inducibility, and to look for the changes in heart rate variability during hydroquinidine treatment. Thirty-five patients with spontaneous and inducible sustained VT were studied. Programmed ventricular stimulation and time and frequency domain analysis of heart rate variability were studied in the control state and 9-12 days after treatment with 300-600 mg of hydroquinidine. In 11 patients (group I), hydroquinidine prevented VT induction. In 24 patients (group II), sustained VT remained inducible during treatment with hydroquinidine. In the control state, heart rate variability was similar in both groups. During treatment with hydroquinidine, heart rate variability tended to decrease in groups I and II, but the changes were significant only in group II: the coefficient of variance (CV) decreased from 13 +/- 4% to 10% +/- 3% (p < 0.01) and low frequency/high frequency amplitude ratio decreased from 4.6 +/- 3.3 to 2.87 +/- 2.42 (p < 0.05). In conclusion, baseline heart rate variability does not differentiate the responders and nonresponders to hydroquinidine. Hydroquinidine decreases heart rate variability in all patients, but principally in those with still inducible VT.

[Influence of anti-arrhythmia agents on heart rate variability]

Since analysis of heart rate variability (HRV) is able to identify subjects at risk of sudden death and as antiarrhythmics can interfere with this prognosis, the objective of this study was to determine whether antiarrhythmics (AA) modified the HRV measured on a 24-hour Holter recording and after rapid ventricular stimulation and whether the initial HRV and its possible modification during treatment with AA were correlated with the results of AA treatment in patients with ventricular tachycardia (sustained VT). The HRV was studied in 50 patients with heart disease and spontaneous sustained VT, reproduced by programmed ventricular stimulation. This analysis was performed at baseline with antiarrhythmic treatment consisting of low-dose beta-blocker and quinidines in 26 patients (group I) or amiodarone in 24 patients (group II). Treatment was effective (i.e. prevented induction of VT) in 9 patients in group I (group la) and 5 patients in group II (group IIa). Treatment was ineffective in the other 17 patients of group I (group Ib) and 19 patients of group II (group IIb). The initial HRV was similar in the patients of groups Ia and Ib or groups IIa and IIb. Temporal analysis did not reveal any significant variation of HRV during AA treatment. In contrast, spectral analysis of HRV and the HRV observed during ventricular stimulation demonstrated a significant reduction of this parameter (p < 0.05 for groups I and II combined).

IN CONCLUSION

the initial HRV is not predictive of the results of treatment. Quinidines and amiodarone tend to decrease HRV regardless of the effect of the AA on the prevention of VT.

Hypertrophic cardiomyopathy: value of atrial programmed electrical stimulation in patients with or without syncope with special reference to the role of atrial arrhythmias

Hypertrophic cardiomyopathy may be associated with both supraventricular and ventricular arrhythmias, which may play a role in the genesis of syncope. The aim of this study was to assess the findings of electrophysiological study and programmed atrial and ventricular stimulation and their possible role in syncope. Programmed atrial and ventricular stimulation using up to two extrastimuli in right atrium and three in right ventricle at three cycle lengths (600, 400 ms and spontaneous) was systematically performed in 56 patients with hypertrophic cardiomyopathy. Thirty seven had unexplained dizzinesses or syncopes (group I) and 19 did not present loss of consciousness (group II). Patients with syncopes had a higher prevalence of induced sustained supraventricular tachyarrhythmia (73%) than those of group II (16%) (P<0.05). Inducible supraventricular tachycardia was the only finding in 16 patients with syncopes. During the follow-up (3 years+/-6 months), empirical antiarrhythmic therapy suppressed the symptoms, except in two patients who developed atrial fibrillation despite therapy. The high incidence of inducible atrial tachycardia of these patients was not correlated with particular Holter findings or echocardiographic data. However, their mean age was rather high (58+/-12 years). In conclusion, atrial tachyarrhythmias may play a role in syncopes of middle-aged patients with hypertrophic cardiomyopathy. Moreover programmed atrial stimulation is an useful means to identify this syncope mechanism.