Predictors of a high defibrillation threshold test during routine ICD implantation.

BACKGROUND: There is growing evidence that routine defibrillation threshold (DFT) testing during implantable cardioverter defibrillator (ICD) implantation is not necessary. However a small group of patients might be at risk if no DFT testing is performed. METHODS: Patients with a new pectoral ICD implantation in our hospital between 2006 and 2014 were included in a retrospective registry. A clinical high DFT was defined as a safety margin <10 J of the maximal device output. Logistic regression for prediction of high DFT was performed using patient characteristics, clinical, echocardiographic and device-related parameters. RESULTS: DFT testing was performed in 788/864 (91.2%) procedures. In 76 (8.8%) patients no DFT testing was performed mainly due to atrial fibrillation, intra-cardiac thrombus, hemodynamic instability or logistical reasons. A high DFT was present in 44 (5.6%) patients. A QRS duration ≥150 ms, a low left ventricular ejection fraction (LVEF ≤25%), a severely dilated left ventricle ≥60 mm and right sided pre-pectoral implantations were univariate predictors of a high DFT. Independent predictors of a high DFT were a LVEF ≤25% (HR 2.195, 95%CI 1.085-4.443) and right sided pre-pectoral implantations (HR 3.135, 95% CI 1.186-8.287). CONCLUSIONS: A high DFT is still present in about 5% of patients and is more frequent in patients with a severely dilated left ventricle, a very low LVEF, right sided pre-pectoral implantation and wider QRS duration. It might be clinically important to continue DFT testing in these high risk patients.

[Inadvertent implantation of a defibrillation lead in the left ventricle through a patent foramen ovale]. / Le cas clinique du mois: Implantation fortuite d'une sonde de défibrillation dans le ventricule gauche au travers d'un foramen ovale perméable.

Inadvertent insertion of a defibrillation lead in the left ventricle is a rare complication generally underdiagnosed after device implantation. Management is not strictly codified due to the small number of observed cases. We report the case of a 78 year-old man in whom the diagnosis has been performed lately during an echocardiography.

[Clinical case of the month. Purulent pericarditis in a patient with pulmonary sarcoidosis]. / Péricardite purulente chez un patient atteint de sarcoïdose pulmonaire.

We report the case of a patient, suffering from pulmonary sarcoidosis, who developed a purulent pericarditis complicated with a cardiac tamponade. The widespread use of antibiotics has progressively reduced the number of purulent pericarditis. However, it remains a serious disease that has to be rapidly diagnosed to be treated timely. We will review the required tests for the diagnosis and the treatment of this pathology that leads to death otherwise. The link with pulmonary sardoidosis is uncertain.

[The student diagnostic vignette. Electrocardiographical criteria for the diagnosis of ventricular tachycardia]. / La vignette diagnostique de l'étudiant. Critères électrocardiographiques d'une tachycardie ventriculaire.

Recording of a regular wide QRS tachycardia is often source of panic and anxiety for the young clinician who has to make the differential diagnosis between ventricular tachycardia and supraventricular tachycardia with aberration associated with fundamentally different vital prognosis. Most of the time, a rigorous approach and a systematic analysis of the electrocardiogram associated with clinical examination allow to obtain the correct diagnosis.

[How I treat...paroxysmal narrow complex QRS tachycardia]. / Comment je traite...une tachycardie paroxystique à QRS fins par réentrée.

Paroxysmal narrow complex QRS tachycardias are a clinical entity characterized by abrupt onset and termination of palpitations, dyspnea, dizziness. They depend on mechanisms of reentry within the atrio-ventricular node or with the participation of an accessory pathway (reciprocating orthodromic tachycardia). We review the clinical and electrocardiographical diagnosis as well as the acute and long term treatment of these tachycardias.

[First episode of atrial fibrillation]. / La vignette thérapeutique de l'étudiant. Premier épisode de fibrillation auriculaire.

We report the case of a patient seen at the outpatient clinic for a first episode of atrial fibrillation. We discussed the steps of the treatment including anticoagulation, rate and rhythm control.

[Adherence to the rules for antithrombotic treatment in atrial fibrillation]. / Adhésion aux règles du traitement anti-thrombotique dans la fibrillation auriculaire.

Adherence to the rules for antithrombotic ment in atrial fibrillation patients significantly reduces the risk of stroke. We review the criteria for the use of anti-vitamin K as well as its daily management in patients with atrial fibrillation.

[The long QT syndrome]. / Le syndrome du QT long congénital.

The congenital long QT syndrome (LQTS) is a hereditary cardiac disease characterized by a prolongation of the QT interval > 440 ms at rest ECG associated with a high risk of ventricular arrhythmias (torsade de pointe). Clinical manifestations are syncope and sudden cardiac death. The implicated genes encode cardiac ion channel subunits or proteins involved in modulating ionic currents. The diagnosis of LQTS can be complex in borderline cases. Etiology, pathogenesis, diagnosis and treatment are discussed.

Functional connectivity in the default network during resting state is preserved in a vegetative but not in a brain dead patient.

Recent studies on spontaneous fluctuations in the functional MRI blood oxygen level-dependent (BOLD) signal in awake healthy subjects showed the presence of coherent fluctuations among functionally defined neuroanatomical networks. However, the functional significance of these spontaneous BOLD fluctuations remains poorly understood. By means of 3 T functional MRI, we demonstrate absent cortico-thalamic BOLD functional connectivity (i.e. between posterior cingulate/precuneal cortex and medial thalamus), but preserved cortico-cortical connectivity within the default network in a case of vegetative state (VS) studied 2.5 years following cardio-respiratory arrest, as documented by extensive behavioral and paraclinical assessments. In the VS patient, as in age-matched controls, anticorrelations could also be observed between posterior cingulate/precuneus and a previously identified task-positive cortical network. Both correlations and anticorrelations were significantly reduced in VS as compared to controls. A similar approach in a brain dead patient did not show any such long-distance functional connectivity. We conclude that some slow coherent BOLD fluctuations previously identified in healthy awake human brain can be found in alive but unaware patients, and are thus unlikely to be uniquely due to ongoing modifications of conscious thoughts. Future studies are needed to give a full characterization of default network connectivity in the VS patients population.

[Clinical case of the month. An elderly patient with bronchiectasis: a case report]. / Bronchectasies chez une dame de 84 ans.

This case report describes a geriatric patient suffering from infected bronchiectasis and severe denutrition. This pathology is common and its treatment clearly defined, but an adapted and specific therapeutic approach, consisting in a global assessment and geriatric multidisciplinary interventions should be performed because of the frailty of the patient. This approach has result in a favorable issue for the patient.

Inferior and anterior QRS fragmentation have different prognostic value in patients who received an implantable defibrillator in primary prevention of sudden cardiac death.

AIMS: QRS fragmentation (fQRS) has been proposed as a predictor of sudden cardiac death (SCD) and all-cause mortality in ischemic (ICM) and non-ischemic cardiomyopathy patients. However the value of fQRS in patients with a LVEF <35% is a matter of debate. METHODS: All consecutive patients with an indication for an ICD in primary prevention of SCD were included in a retrospective registry from 1996 until 2013. Twelve lead electrocardiograms before implant were analyzed for the presence of fQRS in different regions. Adjusted Cox regression analysis for first appropriate ICD shock (AS) and all-cause mortality was performed. RESULTS: In total 407 patients were included with a mean follow-up of 4.2±3.3y (age 60.6±11.9y, 15.7% female and 52.8% ICM). fQRS was present in 46.7% of patients, predominantly inferior (30.7%) followed by anterior (21.4%) and lateral (11.1%) coronary artery territories. fQRS was significantly more prevalent in ICM (p=0.004). Inferior fQRS was an independent predictor of a first AS within 1y (HR 2.55, 95%CI 1.28-5.07) and 3y (HR 1.90, 95%CI 1.14-3.18) after implantation. Whereas, anterior fQRS was an independent predictor of all-cause mortality within 1y (HR 4.58, 95%CI 1.29-16.19), 3y (HR 3.92, 95%CI 1.77-8.65) and the complete follow-up (HR 2.22, 95%CI 1.33-3.69). Lateral fQRS was only a predictor of late (>3y of follow-up) all-cause mortality (HR 2.04, 95%CI 1.09-3.81). CONCLUSIONS: fQRS in a specific coronary artery territory might be promising to discriminate arrhythmic from mortality risk. Inferior fQRS was a predictor of early arrhythmia, while anterior fQRS was related to mortality.

[Arrhythmogenic right ventricular dysplasia]. / Dysplasie arythmogène du ventricule droit.

Arrhythmogenic right ventricular dysplasia is an unfrequent disease that associates ventricular tachycardia with left bundle branch block morphology and right ventricular fibro-fatty degeneration. The etiology, pathogenesis, criteria for diagnosis and treatment are discussed.

[Ghrelin and obesity]. / Ghréline et obésité.

Ghrelin is a peptide hormone secreted by the stomach. It was initially described as a stimulant of growth hormone secretion. Soon, however, it was discovered to play an important role in feeding behaviour in animals and in appetite regulation in man: ghrelin stimulates appetite, and as such is an orexigenic peptide implicated in energy balance mechanisms and weight gain. Abnormal ghrelin activity leads to over- or underweight. Additionally, the efficacy of different treatment strategies against obesity seems to be related to modifications in plasma ghrelin levels. This review summarizes the current knowledge about ghrelin and its implications in obesity medicine.