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Biomedical subjects

A Cribier

Publications and source records attributed to A Cribier.

At least 19 recordsLinked to original sources
PubMed2000

Randomized comparison of two targets in typical atrial flutter ablation.

Typical atrial flutter ablation has become anatomically guided to 2 separate sites within the isthmus at the inferior right atrium: (1) between the inferior vena cava and the tricuspid annulus (anterior side of the isthmus [A]), (2) between the eustachian crest, the coronary sinus ostium and tricuspid annulus (posterior side of the isthmus [P]). We prospectively compared ablation results at these sites in 72 consecutive patients. Patients were randomized in group P or A according to the initial target site. If ablation failed at 1 site after 15 radiofrequency (RF) pulses, the other side of the isthmus was targeted. Before 15 RF pulses, complete bidirectional isthmus block was achieved in 30 of 36 group A patients and in 25 of 36 group P patients, with similar mean RF pulses number, procedure time, and fluoroscopy time. After shifting to the other target, success was finally obtained at P in 2 of 6 group A patients, and at A in 8 of 11 group P patients before a maximum of 30 RF pulses. Among successful patients, number of RF pulses, procedure time, and fluoroscopy time were significantly lower in group A (7.2 +/- 5.4 vs 11.0 +/- 8.1 pulses, p = 0.03; 131 +/- 44 vs 163 +/- 66 minutes, p = 0.03; 31 +/- 19 vs 46 +/- 24 minutes, p = 0.01, respectively). Impairment of atrioventricular (AV) nodal conduction occurred in 5 patients only during ablation at P. AV block was transient in 4 patients and permanent in 1. Although atrial flutter ablation is equally effective at P and A, success seems easier to obtain when A is first targeted. Ablation at P is associated with a significant risk of AV block.

Adult↗
PubMed2000

Assessment of nonuniformity of transmural myocardial velocities by color-coded tissue Doppler imaging: characterization of normal, ischemic, and stunned myocardium.

BACKGROUND: Transmural myocardial contractile performance is nonuniform across the different layers of the left ventricular wall. We evaluated the accuracy of color M-mode tissue Doppler imaging (TDI) to assess the transmural distribution of myocardial velocities and to quantify the severity of dysfunction induced by acute ischemia and reperfusion in the inner and outer myocardial layers. METHODS AND RESULTS: Thirteen open-chest dogs underwent 15 minutes of left anterior descending coronary artery occlusion followed by 120 minutes of reperfusion. M-mode TDI was obtained from an epicardial short-axis view. Systolic velocities were calculated within endocardium and epicardium of the anterior and posterior walls. Regional myocardial blood flow was assessed by radioactive microspheres. Segment shortening was measured by sonomicrometry in endocardium and epicardium of both the anterior and posterior walls. At baseline, endocardial velocities were higher than epicardial velocities, resulting in an inner/outer myocardial velocity gradient. Ischemia caused a significant and comparable reduction in endocardial and epicardial systolic velocities in the anterior wall with the disappearance of the velocity gradient. Systolic velocities significantly correlated with segment shortening in both endocardium and epicardium during ischemia and reperfusion. In the first minutes after reflow, endocardial velocities showed a greater improvement than epicardial velocities, and the velocity gradient resumed although to a limited extent, indicative of stunning. CONCLUSIONS: TDI is an accurate method to assess the nonuniformity of transmural velocities and may be a promising new tool for quantifying ischemia-induced regional myocardial dysfunction.

Animals↗
PubMed2000

Effect of temporal sampling on evaluation of left ventricular ejection fraction by means of thallium-201 gated SPET: comparison of 16- and 8-interval gating, with reference to equilibrium radionuclide angiography.

Gated myocardial single-photon emission tomography (SPET) allows the evaluation of left ventricular ejection fraction (LVEF), but temporal undersampling may lead to systolic truncation and ejection fraction underestimation. The aim of this study was to evaluate the impact of temporal sampling on thallium gated SPET LVEF measurements. Fifty-five consecutive patients (46 men, mean age 62+/-12 years) with a history of myocardial infarction (anterior 31, inferior 24) were studied. All patients underwent equilibrium radionuclide angiography (ERNA) and gated SPET 4 h after a rest injection of 185 MBq (5 mCi) of thallium-201 using either 8-interval (group 1, n=25) or 16-interval gating (group 2, n=30). In group 2, gated SPET acquisitions were automatically resampled to an 8-interval data set. Projection data were reconstructed using filtered back-projection (Butterworth filter, order 5, cut-off 0.20). LVEF was then calculated using commercially available software (QGS). A higher correlation between gated SPET and ERNA was obtained with 16-interval gating (r=0.94) compared with the resampled data set (r=0.84) and 8-interval gating (r=0.71). Bland-Altman plots showed a dramatic improvement in the agreement between gated SPET and ERNA with 16-interval gating (mean difference: -0.10%+/-5%). Using multiple ANOVA, temporal sampling was the only parameter to influence the difference between the two methods. When using 8-interval gating, gated SPET LVEF was overestimated in women and underestimated in men (ERNA minus gated SPET = -4.0%+/-9.6% in women and 3.6%+/-7.6% in men, P=0.01). In conclusion, 16-interval thallium gated SPET offered the best correlation and agreement with ERNA, and should be preferred to 8-interval gated acquisition for LVEF measurement.

Adult↗
PubMed2000

Pacing in prevention of atrial fibrillation: the PIPAF studies.

The PIPAF trials are a set of randomized multicenter studies which seeks to evaluate the potential preventive effect of different modes of pacing in patients with drug refractory paroxysmal atrial fibrillation by means of a permanent pacemaker. The objective of the studies are (1) to significantly prolong the time to first recurrence of atrial arrhythmia and (2) to significantly reduce the cumulative arrhythmia duration. The role of the atrial pacing site (left or right), the overdriving of the sinus rate, and the suppression of the post extrasystolic compensatory pause are evaluated alone or in association, giving rise to four distinct pacing protocols. Over a period of 2 years, 220 patients will be included in 35 centers from 5 different countries.

Atrial Fibrillation↗
PubMed2000

[New invasive cartography techniques in electrophysiology].

Fulguration, a widely used technique in the 80s, has been replaced by radiofrequency ablation. The limited and better controlled intra-cardiac lesions obtained by this method allowed the elimination of a large number of tachycardias with a high success rate. However, there are many arrhythmias, particularly at the atrial level, which are so complex that a limited analysis at a number of points of endocardial recording is inadequate. Recently, a number of systems has been introduced which considerably increased the acuity of observation of arrhythmias and the efficacy of their ablation. First of all, there are improved techniques of classical electrophysiological recording. Then, new systems of temporo-spatial recordings were developed and are described in this article. These use computer systems and enable particularly reliable and detailed approaches to cardiac anatomy and electrophysiology. However, the optimal use of these techniques can only be in specialised centres, by highly trained cardiologists in classical electrophysiology, for which they are complementary to rather than substitute for.

Cardiovascular Physiological Phenomena↗
PubMed2000

[Percutaneous mitral commissurotomy by metallic dilator. Multicenter experience with 500 patients].

A clinical investigation has been conducted since January 1996 with a new valve dilator for percutaneous treatment of mitral stenosis: metallic commissurotome. This new technique is based on the principle of surgical commissurotome but, in its mechanism of action, differs from the usual techniques with balloon catheters. It also offers the unique possibility for multiple utilizations of the same device after resterilization. This article reports a multicenter international investigation involving 500 patients, mean age of 34 +/- 13 years, with a isolated mitral stenosis and an echography score of 7.7 +/- 1.9. Our technique has been feasible in 489 cases (98%) with a success rate (mitral area > 1.5 cm2 without MR > grade 2) of 93%. The transmitral gradient has diminished from 20 +/- 8 mmHg to 4 +/- 3 mm Hg and the mitral area (assessed by planimetry at 24 hrs) has increased from 0.91 +/- 0.20 to 2.12 +/- 0.34 cm2. Complications were uncommon (13 patients: 2.6%) and consisted in 6 tamponades, 5 mitral insufficiencies (one patient required an emergency valve replacement) and 2 neurological transient accidents. The outcomes of this clinical investigation appear most encouraging and at least comparable to those being reported with the commonly used techniques. The most serious complications appear to be closely related to the level of experience with this technique. Considering the possibility to reutilize the metal segments of the apparatus, this technique notably reduces the cost of the procedure per patient and it represents a significant benefit in countries with limited resources.

Adult↗
PubMed1999

How smart should pacemakers Be?

The concept of the "smart" pacemaker has been continuously changing during 40 years of progress in technology. When we talk today about smart pacemakers, it means optimal treatment, diagnosis, and follow-up for patients fitting the current indications for pacemakers. So what is smart today becomes accepted as "state of the art" tomorrow. Originally, implantable pacemakers were developed to save lives from prolonged episodes of bradycardia and/or complete heart block. Now, in addition, they improve quality of life via numerous different functions acting under specific conditions, thanks to the introduction of microprocessors. The devices have become smaller, with the miniaturization of the electrical components, without compromising longevity. Nevertheless, there are still some unmatched objectives for these devices, for example, the optimization of cardiac output and the management of atrial arrhythmias in dual-chamber devices. Furthermore, indications continue to evolve, which in turn require new, additional functions. These functions are often very complex, necessitating computerized programming to simplify application. In addition, the follow-up of these devices is time-consuming, as appropriate system performance has to be regularly monitored. A great many of these functions could be automatically performed and documented, thus enabling physicians and paramedical staff to avoid losing time with routine control procedures. In addition, modern pacemakers offer extensive diagnostic functions to help diagnose patient symptoms and pacemaker system problems. Different types of data are available, and their presentation differs from one company to the other. This huge amount of data can only be managed with automatic diagnostic functions. Thus, the smart pacemaker of the near future should offer high flexibility to permit easy programming of available therapies and follow-up, and extensive, easily comprehensible diagnostic functions.

Arrhythmias, Cardiac↗
PubMed1999

Percutaneous mechanical mitral commissurotomy with a newly designed metallic valvulotome: immediate results of the initial experience in 153 patients.

BACKGROUND: Percutaneous balloon valvotomy has become a common treatment of mitral stenosis, but the cost of the procedure remains a limitation in countries with restricted financial resources, leading to a frequent reuse of the disposable catheters. To overcome this limitation, a reusable metallic valvotomy device has been developed with the goals of both improving the mitral valvotomy results and decreasing the cost of the procedure. METHODS AND RESULTS: The device consists of a detachable metallic cylinder with 2 articulated bars screwed onto the distal end of a disposable catheter whose proximal end is connected to an activating pliers. By the transseptal route, the device is advanced across the valve over a traction guidewire. Squeezing the pliers opens the bars up to a maximum extent of 40 mm. The clinical experience consisted of 153 patients with a broad spectrum of mitral valve deformities. The procedure was successful in 92% of cases and resulted in a significant increase in mitral valve area, from 0.95+/-0.2 to 2. 16+/-0.4 cm2. No increase in mitral regurgitation was noted in 80% of cases. Bilateral splitting of the commissures was observed in 87%. Complications were 2 cases of severe mitral regurgitation (1 requiring surgery), 1 pericardial tamponade, and 1 transient cerebrovascular embolic event. In this series, the maximum number of consecutive patients treated with the same device was 35. CONCLUSIONS: The results obtained with this new device are encouraging and at least comparable to those of current balloon techniques. Multiple uses after sterilization should markedly decrease the procedural cost, a major advantage in countries with limited resources and high incidence of mitral stenosis.

Adolescent↗
PubMed1999

Radiofrequency catheter ablation of common atrial flutter: significance of palpitations and quality-of-life evaluation in patients with proven isthmus block.

BACKGROUND: Creation of a complete bidirectional inferior vena cava-tricuspid annulus isthmus block (CBIB) by radiofrequency catheter ablation is now a well-accepted criterion for prevention of common atrial flutter (AFl) recurrences. However, some patients still complain of palpitations after ablation, and it is not known whether these are related to AFl recurrences or to other arrhythmias. METHODS AND RESULTS: Among 100 consecutive patients referred to our institution for AFl ablation, CBIB was created in 83. There were 54 patients (group A) in whom AFl was the only documented arrhythmia before ablation and 29 patients (group B) in whom atrial fibrillation (AFib) had been documented in addition to AFl. An electrophysiological control study was performed in 40 patients 1 to 3 months after ablation. Arrhythmic events, medications, and functional status were evaluated at midterm follow-up (n=77; 14. 7+/-8.4 months; range, 4 to 34 months). The SF-36 questionnaire and the Symptom Checklist--Frequency and Severity Scale specific for cardiac arrhythmia were used to assess quality of life in 63 patients at long-term follow-up (27.1+/-8.5 months). Recurrence of AFl was documented in only 1 patient 6 months after ablation. AFib was recorded in 28 patients (36.4%), and atypical AFl was found in 3 patients. Thirty-two group A patients (66.7%) and 17 group B patients (58.6%) were still arrhythmia free at midterm follow-up. Even at long-term follow-up and in group B patients, AFl ablation was followed by a clear improvement in quality of life. CONCLUSIONS: Palpitations after creation of CBIB are due mostly to AFib but not to AFl recurrence. This technique provides a significant and persistent clinical benefit and may suppress all atrial arrhythmia in a subset of patients suffering from both AFl and AFib.

Aged↗
PubMed1999

Value and limitations of the Duke criteria for the diagnosis of infective endocarditis.

OBJECTIVES: The purpose of this study was to assess the value and limitations of Duke criteria for the diagnosis of infective endocarditis (IE). BACKGROUND: Duke criteria have been shown to be more sensitive in diagnosing IE than the von Reyn criteria, but the diagnosis of IE remains difficult in some patients. METHODS: Both classifications were applied in 93 consecutive patients with pathologically proven IE. Blood cultures, and transthoracic and transesophageal echocardiography were performed in all patients. RESULTS: Sensitivities for the diagnosis of IE were 56% and 76% for von Reyn and Duke criteria, respectively. Fifty-two patients were correctly classified as "probable IE" by von Reyn and "definite IE" by Duke criteria (group 1). However, discrepancies were observed in 41 patients. Eleven patients (group 2) were misclassified as "rejected" by von Reyn, but were "definite IE" by Duke criteria; this difference could be explained by negative blood cultures and positive echocardiogram in all patients. In eight patients (group 3), the diagnosis of IE was "possible" by von Reyn but "definite" by Duke criteria. This difference was essentially explained by the failure of the von Reyn classification to consider echocardiographic abnormalities as major criteria. Twenty-two patients (group 4) were misclassified as possible IE using Duke criteria, being false negative of this classification. Echocardiographic major criteria were present in 19 patients, but blood cultures were negative in 21 patients. The cause of negative blood cultures was prior antibiotic therapy in 11 patients and Q-fever endocarditis diagnosed by positive serology in three cases. CONCLUSIONS: Twenty-four percent of patients with proved IE remain misclassified as "possible IE" despite the use of Duke criteria, especially in cases of culture-negative and Q-fever IE. Increasing the diagnostic value of echographic criteria in patients with prior antibiotic therapy and typical echocardiographic findings and considering the serologic diagnosis of Q fever as a major criterion would further improve the clinical diagnosis of IE.

Bacteria↗
PubMed1999

Entrainment of typical AV nodal reentrant tachycardia using para-Hisian pacing: evidence for a lower common pathway within the AV node.

INTRODUCTION: Despite the ability to cure atrioventricular nodal reentrant tachycardia (AVNRT) by radiofrequency catheter ablation with a high success rate, the exact localization of the tachycardia circuit is still not well established. The presence of AV nodal tissue between the typical AVNRT circuit and the His bundle, constituting a lower common pathway (LCP), remains controversial. METHODS AND RESULTS: Entrainment of AVNRT during para-Hisian stimulation allows accurate measurement of the His- to- atrial (HA) interval which is part of the same circuit as that of the tachycardia. With an LCP, during tachycardia, there is simultaneous conduction from the low turnaround of the circuit to the atrium (via the fast pathway) and to the His bundle (via the LCP). However, during entrainment by para-Hisian pacing, the impulse has to retrogradely depolarize sequentially the LCP and the fast pathway. Therefore, in the presence of an LCP, the HA interval duration during tachycardia (HAt) should be shorter than that of during entrainment by para-Hisian stimulation (HAe). We considered an LCP present when Hae - HAt was > or = 10 msec. Entrainment of typical AVNRT with para-Hisian stimulation was performed in 23 consecutive patients (21 females) with a mean age of 45+/-17 years. LCP was considered to be present in 18 of 23 patients (78%). In addition, transient His-bundle dissociation from the ongoing tachycardia occurred in seven patients (30%). CONCLUSION: These results support the presence of a LCP during typical AVNRT.

Adolescent↗
PubMed1999

[Distinguishing between physiologic hypertrophy in athletes and primary hypertrophic cardiomyopathies. Importance of tissue color Doppler].

In order to assess the value of Doppler tissue imaging (DTI) in the differentiation of physiological hypertrophy of athletes from primary hypertrophic cardiomyopathy (HCM), the authors compared a group of 20 normal, non-athletic subjects, a group of 43 competitive athletes and a group of 20 patients with mild HCM. In addition to the conventional echocardiographic criteria, the velocity of wall motion at the endocardium and epicardium of the interventricular septum and the posterior wall as well as their gradients, were measured throughout the cardiac cycle. No significant difference was observed between normal subjects and the athletes with respect to velocities and the gradients of velocity. Early diastolic velocities of the posterior wall and interventricular septum were significantly lower than those of normal subjects and athletes. The systolic and early diastolic gradients of velocity of the posterior wall were significantly lower in HCM compared with the normal subjects and athletes. The gradient of velocity between the endocardium and epicardium of the interventricular septum was significantly lower in HCM compared with normal subjects in early diastole and with athletes in systole and early diastole. The best Doppler tissue imaging parameter to differentiate pathological hypertrophy of HCM from physiological hypertrophy of athletes was analysis of the gradient of velocity in early diastole of the posterior wall. A value of 0.7 sec-1 differentiated HCM with a sensitivity of 89%, a specificity of 95% and a diagnostic accuracy of 94%. Doppler tissue imaging is a more sensitive and specific technique than conventional Doppler echocardiography for detecting moderate forms of HCM.

Adult↗
PubMed1999

Thallium-gated SPECT in patients with major myocardial infarction: effect of filtering and zooming in comparison with equilibrium radionuclide imaging and left ventriculography.

UNLABELLED: The effect of filtering and zooming on 201TI-gated SPECT was evaluated in patients with major myocardial infarction. METHODS: Rest thallium (TI)-gated SPECT was performed with a 90 degrees dual-head camera, 4 h after injection of 185 MBq 201TI in 32 patients (mean age 61 +/- 11 y) with large myocardial infarction (33% +/- 17% defect on bull's eye). End diastolic volume (EDV), end systolic volume (ESV) and left ventricular ejection fraction (LVEF) were calculated using a commercially available semiautomatic validated software. First, images were reconstructed using a 2.5 zoom, a Butterworth filter (order = 5) and six Nyquist cutoff frequencies: 0.13 (B5.13), 0.15 (B5.15), 0.20 (B5.20), 0.25 (B5.25), 0.30 (B5.30) and 0.35 (B5.35). Second, images were reconstructed using a zoom of 1 and a Butterworth filter (order = 5) (cutoff frequency 0.20 [B5.20Z1]) (total = 32 x 7 = 224 reconstructions). LVEF was calculated in all patients using equilibrium radionuclide angiocardiography (ERNA). EDV, ESV and LVEF were measured with contrast left ventriculography (LVG). RESULTS: LVEF was 39% +/- 2% (mean +/- SEM) for ERNA and 40% +/- 13% for LVG (P = 0.51). Gated SPECT with B5.20Z2.5 simultaneously offered a mean LVEF value (39% +/- 2%) similar to ERNA (39% +/- 2%) and LVG (40% +/- 3%), optimal correlations with both ERNA (r = 0.83) and LVG (r = 0.70) and minimal differences with both ERNA (-0.9% +/- 7.5% [mean +/- SD]) and LVG (1.1% +/- 10.5%). As a function of filter and zoom choice, correlation coefficients between ERNA or LVG LVEF, and gated SPECT ranged from 0.26 to 0.88; and correlation coefficients between LVG and gated SPECT volumes ranged from 0.87 to 0.94. There was a significant effect of filtering and zooming on EDV, ESV and LVEF (P < 0.0001). Low cutoff frequency (B5.13) overestimated LVEF (P < 0.0001 versus ERNA and LVG). Gated SPECT with 2.5 zoom and high cutoff frequencies (B5.15, B5.20, B5.25, B5.30 and B5.35) overestimated EDV and ESV (P < 0.04) compared with LVG. This volume overestimation with TI-gated SPECT in patients with large myocardial infarction was correlated to the infarct size. A zoom of 1 underestimated EDV, ESV and LVEF compared with a 2.5 zoom (P < 0.02). CONCLUSION: Accurate LVEF measurement is possible with TI-gated SPECT in patients with major myocardial infarction. However, filtering and zooming greatly influence EDV, ESV and LVEF measurements, and TI-gated SPECT overestimates left ventricular volumes, particularly when the infarct size increases.

Female↗
PubMed1999

[Analysis and quantification of longitudinal contraction of the left ventricle in myocardial infarction. Value of Doppler myocardial tissue imaging].

The authors compared the results of conventional 2D echocardiography and those of Doppler tissue imaging in 30 patients in the intensive care unit for acute pulmonary myocardial infarction and 10 normal control subjects, to assess the longitudinal contraction of the left ventricle. Echocardiography was performed in the apical 2 and 4 chamber views to analyse the septal, lateral, posterior and anterior left ventricular walls. Each wall was divided into 3 segments: basal, median and apical. Each segment was scored: 1-normo or hyperkinetic, 2-hypokinetic, 3-akinetic and 4-dyskinetic. Doppler tissue imaging provided the maximum instantaneous velocities in systole and diastole in each segment. In control subjects, the myocardial velocities decreased significantly from the base to the apex, resulting in a systolic and diastolic pressure gradient with each wall between the base and the apex. In patients with myocardial infarction, the myocardial velocities were decreased compared with the control group. Moreover, the myocardial velocity gradient between the base and apex was significantly reduced in the hypo and akinetic walls, both in systole and diastole. These results show that, in myocardial infarction, the longitudinal left ventricular contraction is abnormal and may be analysed and quantified by new indices of myocardial systolic and diastolic function, provided by Doppler tissue imaging.

Echocardiography↗
PubMed1999

201Tl and 99mTc-MIBI gated SPECT in patients with large perfusion defects and left ventricular dysfunction: comparison with equilibrium radionuclide angiography.

UNLABELLED: Left ventricular ejection fraction (LVEF) is a major prognostic factor in coronary artery disease and may be computed by 99mTc-methoxyisobutyl isonitrile (MIBI) gated SPECT. However, 201Tl remains widely used for assessing myocardial perfusion and viability. Therefore, we evaluated the feasibility and accuracy of both 99mTc-MIBI and 201Tl gated SPECT in assessing LVEF in patients with myocardial infarction, large perfusion defects and left ventricular (LV) dysfunction. METHODS: Fifty consecutive patients (43 men, 7 women; mean age 61 +/- 17 y) with a history of myocardial infarction (anterior, 26; inferior, 18; lateral, 6) were studied. All patients underwent equilibnum radionuclide angiography (ERNA) and rest myocardial gated SPECT, either 1 h after the injection of 1110 MBq 99mTc-MIBI (n = 19, group 1) or 4 h after the injection of 185-203 MBq 201Tl (n = 31, group 2) using a 90 degrees dual-head camera. After filtered backprojection (Butterworth filter: order 5, cutoff 0.25 99mTc or 0.20 201Tl), LVEF was calculated from reconstructed gated SPECT with a previously validated semiautomatic commercially available software quantitative gated SPECT (QGS). Perfusion defects were expressed as a percentage of the whole myocardium planimetered by bull's-eye polar map of composite nongated SPECT. RESULTS: Gated SPECT image quality was considered suitable for LVEF measurement in all patients. Mean perfusion defects were 36% +/- 18% (group 1), 33% +/- 17% (group 2), 34% +/- 17% (group 1 + group 2). LVEF was underestimated using gated SPECT compared with ERNA (34% +/- 12% and 39% +/- 12%, respectively; P = 0.0001). Correlations were high (group 1, r= 0.88; group 2, r = 0.76; group 1 + group 2, r = 0.82), and Bland-Altman plots showed a fair agreement between gated SPECT and ERNA. The difference between the two methods did not vary as LVEF, perfusion defect size or seventy increased or when the mitral valve plane was involved in the defect. CONCLUSION: LVEF measurement is feasible using myocardial gated SPECT with the QGS method in patients with large perfusion defects and LV dysfunction. However, both 201Tl and 99mTc-MIBI gated SPECT similarly and significantly underestimated LVEF in patients with LV dysfunction and large perfusion defects.

Electrocardiography↗
PubMed1999

[Indications for electrophysiological investigation of tachycardia].

Cardiologists are often confronted by the situation of discussing the indications for invasive electrophysiological procedures. In this field, the recommendations of American scientific societies have been published but they are relatively dated and require updating. These procedures require the introduction of one or more catheters by a femoral venous or arterial approach, or by the endoesophageal route for positioning at different sites in the heart. The first stage of the procedure is usually to evaluate the electrophysiological properties of the cardiac chamber under investigation; followed by provocative manoeuvres such as electrical stimulation, injection of a drug, the delivery of a CEE electrical shock percutaneously or by an intracardiac radiofrequency stimulation, according to the type of procedure or the centre concerned. Schematically, the indications of these procedures may be determined in different contexts according to the benefits that may be expected in a given clinical situation. This article is devoted to the principal rhythmological situations which may be encountered but, however, the indications of radiofrequency ablation are not discussed.

Bundle of His↗