[Show abstract][Hide abstract] ABSTRACT: A 60-year-old male patient with previous myocardial infarction (30 years ago) presented to our cardiology department for sustained monomorphic ventricular tachycardia. The patient presented multiple episodes of tachycardia treated by his internal cardiac defibrillator. Radiofrequency ablation was proposed as curative treatment. The mechanism of the ventricular tachycardia was demonstrated by electrophysiological study using three-dimensional mapping system: Carto 3 (Biosense Webster). Ventricular tachycardia was induced either mechanically or by programmed ventricular stimulation. The tachycardia cycle length was 380 msec. The voltage map confirmed the presence of the septo-apical aneurysm with a local voltage < 0.5 mV. Activation mapping revealed a figure-in-8 circuit of VT with the entrance point inside the dense scar and the exit point at the border zone (between the aneurysm and the healthy tissue of the left ventricular septo-apical region). Radiofrequency energy was delivered at the isthmus of the tachycardia rendering it uniducible by programmed ventricular stimulation.
Full-text · Article · Oct 2015 · International Journal of Clinical and Experimental Medicine
[Show abstract][Hide abstract] ABSTRACT: Aim:
To determine whether ventricular tachycardia (VT) recurrences in arrhythmogenic RV cardiomyopathy (ARVC) and nonischemic cardiomyopathy (NICM) are related to incomplete ablation or disease progression.
ARVC and NICM patients with 2 substrate maps of the same diseased ventricle with an interprocedural delay of ≥12months were included. Disease progression was defined as ≥1 factor: Scar area progression (PROG,+5%), ventricular remodeling [dilatation (+25ml) or decreased ejection fraction (-5%EF)]. Incomplete ablation was defined as index VT recurrence or ablation in previously unablated regions inside index scar without PROG.
Twenty patients from 9 centers were included (80% male 55±16 years, 7 ARVC and 13 NICM, LVEF 43±14%). Mean delay was 28±18 months. Disease progression occurred in 75% with ventricular remodeling in 70%: Ventricular dilation in 45% [ARVC (71%); NICM (38%)], decreased EF in 60% [RVEF in ARVC (71%); LVEF in NICM (54%)] and scar progression in 50% [in ARVC (57%): and in NICM (46%)]. Index VT recurrence was observed in 40%. Redo ablation sites were located in previously unablated regions inside the index scar in 70% of patients. VT recurrence following the second procedure was seen in 25%. Fifteen percent died during a follow-up of 17±17months.
Disease progression is the rule in ARVC and NICM while scar progression occurs in half. However, even if disease progression is frequently observed, incomplete index ablation is the most common finding, strongly suggesting the need for more extensive ablation. This article is protected by copyright. All rights reserved.
No preview · Article · Oct 2015 · Journal of Cardiovascular Electrophysiology
[Show abstract][Hide abstract] ABSTRACT: Left ventricular posterior fascicular tachycardia (LVPFT) is an idiopathic
form of VT characterized by right bundle branch block morphology and left axis deviation. The mechanism of LPFVT is thought to be localized reentry close to the posterior fascicle. We present the case of a 24-year-old medical student who was admitted to the emergency department complaining of palpitations. The ECG showed an aspect suggestive of LVPFT. Vagal maneuvers, adenosine and i.v. Metoprolol were ineffective in terminating the arrhythmia. Conversion to sinus rhythm was obtained 10 h later, with i.v Amiodarone. The ECG in sinus rhythm showed left posterior fascicular block. Because antiarrhythmic drugs were not desired by the patient, VT ablation was proposed. The electrophysiological study identified the mechanism of arrhythmia to be reentry using the slowly conducting verapamil-sensitive fibers as the antegrade limb and the posterior fascicle as the retrograde limb. Radiofrequency applications near the posterior fascicle, in the lower half of the interventricular septum, at the junction of the two proximal thirds with the distal third interrupted the tachycardia and made it non-inducible at programmed stimulation. The case is unusual as the patient had a left posterior fascicular block during sinus rhythm before ablation. This demonstrates that the reentry circuit of VT does not need antegrade conduction through the posterior fascicle for perpetuation.
[Show abstract][Hide abstract] ABSTRACT: Ventriculoatrial (VA) conduction can have negative consequences for patients with implanted pacemakers and defibrillators. There is concern whether impaired VA conduction could recover during stressful situations. Although the influence of isoproterenol and atropine are well established, the effect of adrenaline has not been studied systematically. The objective of this study was to determine if adrenaline can facilitate recovery of VA conduction in patients implanted with pacemakers.
A prospective study was conducted on 61 consecutive patients during a 4 month period (April to July 2014). The presence of VA conduction was assessed during the pacemaker implantation procedure. In case of an impaired VA conduction, adrenaline infusion was used as a stress surrogate to test conduction recovery.
The indications for pacemaker implantation were: sinus node dysfunction in 18 patients, AV block in 40 patients, binodal dysfunction (sinus node+ AV node) in 2 patients and other (carotid sinus syndrome) in 1 patient. In the basal state, 15/61 (24.6%) presented spontaneous VA conduction and 46/61 (75.4%) had no VA conduction. After administration of adrenaline, there was VA conduction recovery in 5/46 (10.9%) patients.
Adrenaline infusion produced recovery of VA conduction in 10.9% of patients with absent VA conduction in a basal state. Recovery of VA conduction during physiological or pathological stresses could be responsible for the pacemaker syndrome, PMT episodes or certain ICD detection issues. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Ventricular fibrillation in the absence of structural heart disease represents an important mechanism of sudden cardiac death. It is initiated by triggers originating in the distal Purkinje fibers, arising from either the right or the left ventricle. Catheter ablation of these triggers has the potential of terminating the arrhythmia and preventing recurrence.We present the case of an electrical storm in a 39-year old female patient with no cardiac past medical history, with recurrent episodes of idiopathic ventricular fibrillation, who was referred to our hospital for repeated episodes of syncope. The 12-lead ECG showed the presence of frequent ventricular premature beats (VPB), having a left-bundle branch block morphology and superior axis, with an "R on T" phenomenon, initiating non-sustained episodes of ventricular fibrillation. Using a three-dimensional, non-fluoroscopic mapping system (CARTO 3, Biosense Webster), the origin of the ventricular premature beat responsible for the initiation of VFib was identified and successfully ablated.Catheter ablation of idiopathic ventricular fibrillation using a 3-dimensional mapping system is a feasible therapeutic option for patients with this type of arrhythmia.
Full-text · Article · Mar 2015 · Egyptian Heart Journal
[Show abstract][Hide abstract] ABSTRACT: The aim of study was to report different and unusual patterns of preexcitation syndrome (PS) noted in patients referred for studied for poorly-tolerated arrhythmias and their frequency. Electrophysiologic study (EPS) is an easy means to identify a patient with PS at risk of serious events. However the main basis for this diagnosis is the ECG which associates short PR interval and widening of QRS complex with a delta wave.
ECGs of 861 patients in whom PS related to an atrioventricular accessory pathway (AP) was identified at electrophysiological study (EPS), were studied.
The most frequent unusual presentation (9.6%) was the PS presenting with a normal or near normal ECG, noted preferentially for left lateral AP and rarely for posteroseptal or right lateral location. More exceptional (0.1%) was the presence of a long PR interval, which did not exclude a rapid conduction over AP. The association of a complete AV block with symptomatic tachycardias was exceptional (0.3%) and was shown related to a rapid conduction over AP after isoproterenol. Most of the presented patients were at high-risk at EPS.
The diagnosis of PS is not always evident and symptoms should draw attention to minor abnormalities and lead to enlarge indications of EPS, only means to confirm or not PS.
Full-text · Article · Apr 2014 · International Journal of Cardiology
[Show abstract][Hide abstract] ABSTRACT: The most commonly used drug for the facilitation of supraventricular tachycardia (SVT) induction in the electrophysiological (EP) laboratory is isoprenaline. Despite isoprenaline's apparent indispensability, availability has been problematic in some European countries. Alternative sympatomimethic drugs such as adrenaline have therefore been tried. However, no studies have determined the sensitivity and specificity of adrenaline for the induction of SVT. The objective of this study was to determine the sensitivity and specificity of adrenaline for the induction of SVT.METHODS AND RESULTS: Between February 2010 and July 2013, 336 patients underwent an EP study for prior documented SVT. In 66 patients, adrenaline was infused because tachycardia was not induced under basal conditions. This group was compared with 30 control subjects with no history of SVT. Programmed atrial stimulation was carried out during baseline state and repeated after an infusion of adrenaline (dose ranging from 0.05 mcg/kgc to 0.3 mcg/kgc). The endpoint was the induction of SVT. Among 66 patients with a history of SVT but no induction under basal conditions, adrenaline facilitated induction in 54 patients (82%, P < 0.001). Among the 30 control subjects, SVT was not induced in any patient (0%) after infusion. Adrenaline was generally well tolerated, except for two patients (3.0%), where it had to be discontinued due to headache and high blood pressure or lumbar pain.CONCLUSION: Adrenaline infusion has a high sensitivity (82%) and specificity (100%) for the induction of SVT in patients with prior documented SVT. Therefore, it could serve as an acceptable alternative to isoprenaline, when the latter is not available.
[Show abstract][Hide abstract] ABSTRACT: Patients with well-tolerated sustained monomorphic ventricular tachycardia (SMVT) and left ventricular ejection fraction (LVEF) over 30% may benefit from a primary strategy of VT ablation without immediate need for a 'back-up' implantable cardioverter-defibrillator (ICD).
One hundred and sixty-six patients with structural heart disease (SHD), LVEF over 30%, and well-tolerated SMVT (no syncope) underwent primary radiofrequency ablation without ICD implantation at eight European centres. There were 139 men (84%) with mean age 62 ± 15 years and mean LVEF of 50 ± 10%. Fifty-five percent had ischaemic heart disease, 19% non-ischaemic cardiomyopathy, and 12% arrhythmogenic right ventricular cardiomyopathy. Three hundred seventy-eight similar patients were implanted with an ICD during the same period and serve as a control group. All-cause mortality was 12% (20 patients) over a mean follow-up of 32 ± 27 months. Eight patients (40%) died from non-cardiovascular causes, 8 (40%) died from non-arrhythmic cardiovascular causes, and 4 (20%) died suddenly (SD) (2.4% of the population). All-cause mortality in the control group was 12%. Twenty-seven patients (16%) had a non-fatal recurrence at a median time of 5 months, while 20 patients (12%) required an ICD, of whom 4 died (20%).
Patients with well-tolerated SMVT, SHD, and LVEF > 30% undergoing primary VT ablation without a back-up ICD had a very low rate of arrhythmic death and recurrences were generally non-fatal. These data would support a randomized clinical trial comparing this approach with others incorporating implantation of an ICD as a primary strategy.
No preview · Article · Feb 2014 · European Heart Journal
[Show abstract][Hide abstract] ABSTRACT: Background
Most postinfarct ventricular tachycardias (VTs) are sustained by a reentrant mechanism. The “protected isthmus” of the reentrant circuit is critical for the maintenance of VTs and the target for catheter ablation. Various techniques based on conventional electrophysiology and/or detailed three-dimensional (3D) reconstruction of the VT circuit are used to unmask this isthmus.
The purpose of this study was to assess pace-maps (PMs) to identify postinfarct VT isthmuses. We hypothesized that an abrupt change in paced QRS morphology may be used to identify a VT isthmus and be targeted for successful ablation.
High-density 3D PMs were matched to the subsequent 3D endocardial reentrant VT activation mapping in 10 patients (8 men; age 70.7 ± 10.8 years) who underwent successful postinfarct VT ablation. At each pacing site in a given patient, the 12-lead ECG recorded during pacing was compared to that of VT, with the resulting matching percentage (up to 100% for perfect matches) allocated to this point to generate color-coded PMs.
With respect to VT isthmuses, the best percentages of matching were found in the exit zones and isthmus exit part (89% ± 8% and 84% ± 7%, respectively) and the poorest adjacent to scar border in the outer entrance zones (23% ± 28%), in the entrance zones (39% ± 34%), and in the entrance part of the isthmus (32% ± 26%). The color-coded sequence (from the best to the poorest matching sites) on the PMs revealed figure-of-eight pictures matching the VT activation time maps and identifying VT isthmuses.
Pace-mapping is useful for unmasking VT isthmuses in patients with well-tolerated postinfarct endocardial reentrant VTs.
No preview · Article · Feb 2014 · Heart rhythm: the official journal of the Heart Rhythm Society
[Show abstract][Hide abstract] ABSTRACT: Purpose of the study: Typical Atrioventricular (AV) Node Re-entrant Tachycardia (AVNRT) occurs in patients with dual AV nodal pathway, a rapid pathway used for retrograde conduction and a slow pathway used for the anterograde conduction. In sinus rhythm the patients have generally the signs of conduction through the rapid pathway with a normal or short PR interval. The purpose of the study was to evaluate the prevalence of patients with 1st degree AV block and with AVNRT and their clinical characteristics.
Methods: 1040 patients, 366 males, 665 females were admitted for typical AVNRT. They were aged from 6 to 90 years (mean age 50±19). Initial ECG and clinical data were collected. Electrophysiological study was systematic.
Results: Spontaneous 1st degree AV Block (AVB) was rare and noted in 8 patients. The prevalence of the association 1st degree AV Block and AVNRT was 0.8%. AVB was suprahisian in 7 of 8 and infrahisian in one of them. Five patients complained of AVNRT at exercise. Two patients had an ischemic heart disease. Patients with AVB were significantly older (71.5±16 years) than patients without AVB (50±19) (p<0.002). AVNRT was induced in control state in 5 patients. The rate of tachycardia was slow between 130 and 160 bpm. AVNRT was induced after isoproterenol in 3 patients and the rate was higher (180 to 200 bpm). Ablation of slow pathway was performed in 7 patients. Transitory 2nd degree AVB was noted in 1 patient. AVNRT was not inducible after ablation. PR interval remained unchanged. At atrial pacing, the rate of 2nd degree AVB occurrence decreased, due to the disappearance of the conduction through the slow pathway. Two patients developed transitory well-tolerated 2nd degree AVB one day after ablation. One patient presented apparent sinus bradycardia related to a concealed conduction through AV node. One year after ablation none of the patients required pacemaker implantation and patients were free of tachycardia.
Conclusions: The occurrence of AVNRT in patients with 1st degree AV block is exceptional and concerns old patients. The prevalence was 0.8%. Ablation of slow pathway might be safely performed without a need of pacemaker implantation. Transitory 2nd degree AVB can be noted the day after ablation.
Preview · Article · Aug 2013 · European Heart Journal
[Show abstract][Hide abstract] ABSTRACT: Unlabelled:
Little is known about the epidemiology of 1:1 atrial flutter (AFL). Our objectives were to determine its prevalence and predisposing conditions.
1037 patients aged 16 to 93 years (mean 64±12) were consecutively referred for AFL ablation. 791 had heart disease (HD). Patients admitted with 1/1 AFL were collected. Patients were followed 3±3 years.
1:1 AFL-related tachycardiomyopathy was found in 85 patients, 59 men (69%) with a mean age of 59±12 years. The prevalence was 8%. They were compared to 952 patients, 741 men (78%, 0.04), with a mean age of 65±12 years (0.002) without 1:1 AFL. Factors favoring 1:1 AFL was the absence of HD (35 vs 23%, 0.006), the history of AF (42 vs 30.5%)(0.025) and the use of class I antiarrhythmic drugs (34 vs 13%)(p<0.0001), while use of amiodarone or beta blockers was less frequent in patients with 1:1 AFL (5, 3.5%) than in patients without 1:1 AFL (25, 15%) (p<0.0001, 0.03). The failure of ablation (9.4 vs 11%), ablation-related complications (2.3 vs 1.4%), risk of subsequent atrial fibrillation (AF) (20 vs 24%), risk of AFL recurrences (19 vs 13%) and risk of cardiac death (5 vs 6%) were similar in patients with and without 1:1 AFL.
The prevalence of 1:1 AFL in patients admitted for AFL ablation was 8%. These patients were younger, had less frequent HD, had more frequent history of AF and received more frequently class I antiarrhythmic drugs than patients without 1:1 AFL. Their prognosis was similar to patients without 1:1 AFL.
No preview · Article · Apr 2013 · International journal of cardiology
[Show abstract][Hide abstract] ABSTRACT: Background:
The occurrence of ventricular tachycardia (VT) after myocardial infarction is associated with poorer prognosis. In such patients, implantable cardioverter-defibrillators are recommended. Catheter ablation of VT is currently recommended only as an adjunctive therapy. Whether a successful VT ablation alone might be a viable strategy in some of these patients, however, remains unknown. The aim of the present study was to evaluate this strategy.
Methods and results:
Between January 2002 and December 2011, 189 patients with cardiomyopathy underwent 259 VT ablations in our center. Forty-five patients (mean age, 65.2±9.6 years; 91% men) with a history of myocardial infarction and mean left ventricular ejection fraction of 39.7±9.7% matched the study criteria and were included in this analysis. Acute success was obtained in 40 of 45 patients (88.9%). During a follow-up, on the basis of our stepwise algorithm (using acute success, repeat electrophysiological study, and recurrence of VT), 19 of 45 patients (42.2%) underwent implantable cardioverter-defibrillators implantation. During a median follow-up of 4.5 (interquartile range, 2.1-7.0) years, all-cause mortality occurred in 14 of 45 patients (31.1%). Using multivariate Cox regression analysis, age (hazard ratio, 1.13; 95% confidence interval, 1.03-1.22; P=0.007) was the only independent predictor of mortality, whereas implantable cardioverter-defibrillators implantation was not (hazard ratio, 0.54; 95% confidence interval, 0.18-1.64; P=0.28)
Our results suggest that a stepwise approach to the management of VT with ablation as a first-line treatment in postinfarct patients presenting with VT might be a reasonable option. Further studies are required to confirm these results.
Full-text · Article · Mar 2013 · Circulation Arrhythmia and Electrophysiology
[Show abstract][Hide abstract] ABSTRACT: Background:
Syncope in Wolff-Parkinson-White syndrome (WPW) is without relationship with WPW or reveals a poorly tolerated arrhythmia. Electrophysiologic study (EPS) is recommended. The purpose of the study was to evaluate the influence of the patient's age on the causes and prognosis of syncope.
A total of 98 patients, mean age 35 ± 18 years, with WPW were admitted for syncope. Note that 29 were aged between 9 and 19 years (mean 15 ± 3) (children and teenagers/group I), 45 between 20 and 49 years (mean 34 ± 8) (adults/group II), and 24 between 50 and 70 years (mean 60 ± 8) (elderly/group III). EPS consisted of atrial pacing and programmed atrial stimulation in control state and after isoproterenol.
Potentially malignant form (rapid conduction in accessory pathway >240 beats/min in control state or >300 beats/min after isoproterenol and atrial fibrillation [AF] induction) was more frequent in group I (34%) than in groups II (7%) (P < 0.002) and III (0%) (P < 0.001). Orthodromic atrioventricular reentrant tachycardia (AVRT) and AF were induced as frequently in groups I (59, 34%), II (47, 15.5%), and III (54, 17%). AVRT was induced in all but one patient with malignant form. EPS was as frequently negative in groups I (27.5%), II (44%), and III (37.5%). Natural follow-up (mean 8 ± 6 years) indicated a favorable prognosis, only related to AVRT induction. Induced AF was without significance.
Data in syncope and WPW syndrome depended on age: electrophysiological malignant form was frequent in children/teenagers, rare in adults, and absent in elderly. AVRT, the main cause of syncope, was as frequent in all ranges of age. AF's induction alone had no significance. Final prognosis was favorable.
No preview · Article · Feb 2013 · Pacing and Clinical Electrophysiology
[Show abstract][Hide abstract] ABSTRACT: Unlabelled:
Sex-related differences were not reported for the atrial flutter (AF). The purpose of the study was to look for the influence of gender on indications, clinical data and long-term results of AFl ablation.
985 patients, [227 females (23%)] were referred for radiofrequency AFl ablation. Clinical history, echocardiography were collected. Patients were followed from 3 months to 10 years.
Age of women and men was similar (65.5 ± 12 vs 64 ± 11.5 years). Underlying heart disease (HD) was as frequent in women as men (77.5 vs 77%), but women had more congenital HD (10 vs 2%;p<0.001), valvular HD (18 vs 10%;p<0.002), hypertensive HD (24 vs 18%;p<0.05), and less chronic lung disease (5 vs 10%;p<0.01), and ischemic HD (5 vs 20%;p<0.001). Atrial fibrillation (AF) history was more frequent in women (36 vs 27%;p<0.001). AFl-related tachycardiomyopathy (4.5 vs 8%;p<0.03) was more frequent, but 1/1 AFl (10 vs 6%;p=NS) as frequent. Failure of ablation (16 vs 10%;p<0.01), ablation-related major complications (3.5 vs 0.9%;p<0.005) were more frequent in women. After 3 ± 3 years, AFl recurrences were as frequent in women and men (10 vs 14%), AF occurrence more frequent in women (34 vs 19.5%; p<0.001). After excluding patients with previous AF, AF risk remained higher in women (19 vs 12%; p<0.004).
In patients admitted for ablation, AFL was less common in women than in men, despite similar age and similarly prevalent HD. More than men, women had frequent AF history, a higher risk of failure of ablation and AFl ablation-related major complications and a higher risk of AF after ablation.
Full-text · Article · Jan 2013 · International journal of cardiology
[Show abstract][Hide abstract] ABSTRACT: Aims Orthodromic atrioventricular reentrant tachycardia (ORT) is the most common arrhythmia at electrophysiological study (EPS) in patients with pre-excitation. The purpose of the study was to determine the clinical significance and the electrophysiological characteristics of patients with inducible antidromic tachycardia (ADT).Methods and resultsElectrophysiological study was performed in 807 patients with a pre-excitation syndrome in control state and after isoproterenol. Antidromic tachycardia was induced in 63 patients (8%). Clinical and electrophysiological data were compared with those of 744 patients without ADT. Patients with and without ADT were similar in term of age (33 ± 18 vs. 34 ± 17), male gender (68 vs. 61%), clinical presentation with spontaneous atrioventricular reentrant tachycardia (AVRT) (35 vs. 42%), atrial fibrillation (AF) (3 vs. 3%), syncope (16 vs. 12%). In patients with induced ADT, asymptomatic patients were less frequent (24 vs. 37%; <0.04), spontaneous ADT and spontaneous malignant form more frequent (8 vs. 0.5%; <0.001) (16 vs. 6%; <0.002). Left lateral accessory pathway (AP) location was more frequent (51 vs. 36%; P < 0.022), septal location less frequent (40 vs. 56%; P < 0.01). And 1/1 conduction through AP was more rapid. Orthodromic AVRT induction was as frequent (55.5 vs. 55%), but AF induction (41 vs. 24%; P < 0.002) and electrophysiological malignant form were more frequent (22 vs. 12%; P < 0.02). The follow-up was similar; four deaths and three spontaneous malignant forms occurred in patients without ADT. When population was divided based on age (<20/≥20 years), the older group was less likely to have criteria for malignant form.Conclusion
Antidromic tachycardia induction is rare in pre-excitation syndrome and generally is associated with spontaneous or electrophysiological malignant form, but clinical outcome does not differ.
[Show abstract][Hide abstract] ABSTRACT: The number of scar-related ventricular tachycardia (VT) ablation procedures is increasing worldwide. This is certainly due to the ever growing number of patients implanted with an implantable cardioverter defibrillator in whom an ablation procedure may be required to better control the ventricular arrhythmia burden, but is also likely related to our better understanding of the arrhythmias mechanisms as well as the improvement of the mapping techniques during the last 15 years. Most VTs, especially those arising after myocardial infarction, depend on a critical isthmus. Defining precisely the critical isthmus of postinfarct VT may be challenging, particularly when the arrhythmia is poorly tolerated. In the literature, there are extensive data concerning the value of conventional electrophysiological techniques, especially entrainment mapping in association with postpacing interval measurements, regarding the identification of postinfarct VT isthmuses. There are, however, other--sometimes emerging--approaches to image critical postinfarct VT channels. We have summarized these, reviewing data from the published literature as well as our own experience.
No preview · Article · May 2012 · Pacing and Clinical Electrophysiology