MNS ablation is a feasible treatment for various human arrhythmias, with a high success rate. Mapping with a magnetic catheter is safe. However, magnetic ablation of typical atrial flutter remains challenging, probably because of insufficient pressure for cavotricuspid isthmus ablation.

At the time of initial complete bidirectional isthmus conduction block (CBIB) identification as the best predictor of long-term success for ablation of typical atrial flutter, the assessment required detailed mapping of activation at both sides of the ablation line during proximal coronary sinus (PCS) and antero-inferior right atrium (AIRA) pacing. 1 Complete block after radiofrequency applications was clearly associated with a change of activation pattern at the AIRA compared to baseline and this implied the use of three catheters (one for mapping each side of the ablation zone and one for ablation). Like any new concepts it brought as many questions as answers. Technically speaking mapping of the AIRA had to be done as anteriorly as possible as the circuit in its typical form is peritricuspidian. Standard multipolar catheters bend in a single plane and are thus hard to manipulate in this area as they have a tendency to stay posterior in the lateral right atrium. In addition, even if they stay close to the tricuspid annulus, the tip of the catheter rarely reaches the area close from the ablation line. As a consequence, this leaves a large unmapped area which is why we favored the use of multipolar preshaped catheters (commonly referred to as "Halo catheter." Most of these incorporate a high number of electrodes (typically 20) but all dipoles are not equally useful and indeed the two most distal are sufficient to assess conduction in the immediate vicinity of the ablation line. In practice, we use a decapolar Halo catheter for reasons explained below. Several methods have later been proposed and the purpose of this article is to review the technique used for assessment of the conduction block during catheter ablation of atrial flutter in our laboratory.Surface ECG changes have been proposed with CBIB as appearance of a purely descending lateral RA wavefront during PCS pacing accompanied by a positive second part of the paced P wave, but this lacks sensitivity and specificity and we do not use it. Unipolar mapping using the ablation electrode has proven effective when a change from a RS pattern before block to a single monophasic R after identifies the end of the activation wave front. We also do not use it as it seems a bit more difficult to interpret and has not been stud-

We report a case where real-time 3D TEE proved the non-thrombotic nature of a particular pectinated muscle arrangement within the LAA.

Typical atrial flutter is due to a counterclockwise macro-re-entry circuit localized in the right atrium with a surface ECG pattern showing predominantly negative F waves in the inferior leads and positive F waves in V1. Recently it has been proposed to classify atrial flutter on the basis of its cavo-tricuspid isthmus dependence rather than on the ECG pattern. Therefore some atrial flutters are considered typical even if the ECG does not exhibit a typical pattern. This is the case for reverse typical atrial flutter, lower loop re-entry and partial-isthmus-dependent short circuit flutter. The term atypical flutter refers to a non-isthmus dependent flutter. Usually these patients have had previous cardiac surgery with a right or left atriotomy. Flutter involving a spontaneous right atrial scar is not uncommon.

BackgroundHelcococcus kunzii is a facultative anaerobic bacterium that was first described by Collins et al. in 1993, and was initially considered as a commensal of the human skin, in particular of lower extremities. Human infections caused by H. kunzii remain rare with only a few cases published in the pubmed database. Nevertheless recent reports indicate that this microorganism has to be considered as an opportunistic pathogen that can be involved in severe infections in human. To the best of our knowledge, we describe here the first known case of infectious endocarditis caused by H. kunzii.Case presentationA 79 year-old man reporting severe polyvascular medical history attended the emergency ward for rapid deterioration of his general state of health. After physical examination and paraclinical investigations, the diagnosis of infectious endocarditis on native mitral valve caused by Helcococcus kunzii was established based on Dukes criteria. MALDI-TOF mass spectrometry and 16S rDNA sequencing allowed an accurate identification to the species level of Helcococcus kunzii. The patient was successfully treated by a medico-surgical approach. The treatment consisted in intravenous amoxicillin during four weeks and mitral valve replacement with a bioprosthestic valve. After an in depth review of patient’s medical file, the origin of infection remained unknown. However, a cutaneous portal of entry cannot be excluded as the patient and his General Practitioner reported chronic ulcerations of both feet.ConclusionsWe describe here the first case of endocarditis caused by H. kunzii in an elderly patient with polyvascular disease. This report along with previous data found in the literature emphasizes the invasive potential of this bacterial species as an opportunistic pathogen, in particular for patient with polyvascular diseases. MALDI-TOF mass spectrometry and 16S rDNA sequencing are reliable tools for H. kunzii identification. We also sequenced in this work H.kunzii type strain 103932T CIP and deposited in the Genbank under accession number KM403387. We noticed a 14 base difference between our sequence and the original sequence deposited by Collins et al. under Genbank accession number X69837. Hopefully, the spread of next generation sequencing tools would lead to a more accurate classification of clinical strains.