Fulvio Gabbarini - Academia.edu (original) (raw)

Papers by Fulvio Gabbarini

Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology, 2021

Background. The long QT syndrome (LQTS), a leading cause of sudden death under 20 years of age, i... more Background. The long QT syndrome (LQTS), a leading cause of sudden death under 20 years of age, is due to mutations in genes which encode ion channels involved in the control of ventricular repolarization. In a prospective study on 34,000 neonates we found that a prolonged QT interval was associated with a 41 times greater risk for sudden infant death syndrome (SIDS) and, recently, in a case-control study on 201 cases of SIDS we found disease-causing LQTS mutations in 9.5% of the victims. Based on these results the Italian Ministry of Health is considering the possibility of introducing in the National Health Service an electrocardiographic (ECG) screening program in the first month of life to identify infants affected by LQTS. A realistic assessment of the prevalence of infants with LQTS becomes necessary. Methods. An ECG was recorded in the first month of life in 44,596 neonates. The QT interval was measured and corrected for heart rate according to the Bazett’s formula (QTc). In the neonates with a markedly prolonged QT (QTc ≥ 470 msec) molecular screening of the LQTS genes was performed. Results. A QTc between 440 and 470 msec was observed in 611 neonates (1.4%). A QTc ≥ 470 ms was found in 31 neonates (0.07%). Genetic analysis was performed in 28/31 (90%) neonates and LQTS mutations were identified in 14 of them (50%): 8 were LQT1, 4 LQT2 and 2 LQT3. Besides one de novo mutation, all other cases were familial and genetic analysis identified additional family members (37/72, 51%) affected by LQTS who had not been previously diagnosed. Within these 28 infants QTc was longer in the positively genotyped neonates (493±22 vs 479±6 ms, p=0.037) and a LQTS mutation was identified in all the neonates (n=5) with a QTc > 496 ms. Conclusions. An ECG performed in the first month of life, with genetic analysis in selected cases, allows early diagnosis of infants with sporadic and familial forms of LQTS, thus leading to institution of effective therapies aimed at preventing sudden death either in infancy or later on in life, not only in the neonates but also in their affected family members. This study also provides a first data-based estimate of LQTS prevalence, likely to be between 1/3,000 and 1/2,500 live births.

EuroIntervention, 2012

Limited data exists on midterm results concerning paediatric interventions on stenotic or occlude... more Limited data exists on midterm results concerning paediatric interventions on stenotic or occluded systemic veins following indwelling lines, cardiac surgery, or catheterisations. The purpose of this study was to report our acute and intermediate results concerning patients with (Group A) and without (Group B) congenital heart diseases (CHD) over a 10-year period. From January 2000 to December 2010, 32 patients (23 in Group A and nine in Group B, respectively) underwent 39 interventional catheterisations aimed to dilate or recanalise occluded iliofemoral veins, inferior or superior venae cavae. Initial and follow-up catheterisation data were reviewed retrospectively. Midterm results were evaluated by means of echography, angiography, and CT scan in all 15 and 17 patients, respectively. Median age and weight of all patients at catheterisation were five years (range 0.1-18) and 15 kg (range 2-60), respectively. Fifty-two stents were implanted in 29 patients (32 vessels). In 25 patients 28 vessels were occluded and required recanalisation. There were no major complications. In all but three patients it was possible to treat the lesion. There were two procedural complications (5.1%): one acute stent occlusion and one local dissection. At a median follow-up of 2.5 years (range 1-10) we observed six complications of stenting (11.5%): two fractures, two occlusions and two restenoses. Interventional catheterisation of stenotic or occluded systemic veins grants good immediate results at a low rate of complication. Stent dilatation or recanalisation may open the vessel for use during future procedures. However, long-term results are yet to be established.

Pacing and Clinical Electrophysiology, 2015

Background. Fluoroscopic catheter ablation of cardiac arrhythmias in pediatric patients exposes t... more Background. Fluoroscopic catheter ablation of cardiac arrhythmias in pediatric patients exposes the patients to the potential risk of radiation considering the sensitivity of this population and its longer life expectancy. We evaluated the feasibility, safety and efficacy of accessory pathway (AP) ablation guided by CARTO3 electroanatomic mapping (EAM) system with both cryoenergy and radiofrequency (RF) energy in order to avoid x-ray exposure in pediatric patients.

Pacing and Clinical Electrophysiology, 2013

Anatomical considerations and risks related to x-ray exposure make atrioventricular nodal reentra... more Anatomical considerations and risks related to x-ray exposure make atrioventricular nodal reentrant tachycardia (AVNRT) ablation in pediatric patients a concerning procedure. We aimed to evaluate the feasibility, safety, and efficacy of performing fluoroless slow-pathway cryoablation guided by the electroanatomic (EA) mapping in children and adolescents. Twenty-one consecutive patients (mean age 13.5 ± 2.4 years) symptomatic for AVNRT were prospectively enrolled to right atrium EA mapping and electrophysiological study prior to cryoablation. Cryoablation was guided by slow-pathway potential and performed using a 4-mm-tip catheter. Sustained slow-fast AVNRT was inducible in all the patients with a dual AV nodal physiology in 95%. Acute success was achieved in 100% of the patients with a median of two cryo-applications. Fluoroless ablation was feasible in 19 patients, while in two subjects 50 seconds and 45 seconds of x-ray were needed due to difficult progression of the catheters along the venous system. After a mean follow-up of 25 months, AVNRT recurred in five patients. All the recurrences were successfully treated with a second procedure. In three patients, a fluoroless cryoablation with a 6-mm-tip catheter was successfully performed, while in the remaining two patients, a single pulse of 60 seconds of radiofrequency energy was applied under fluoroscopic monitoring. No complications occurred. Combination of EA mapping systems and cryoablation may allow to perform fluoroless slow-pathway ablation for AVNRT in children and adolescents in the majority of patients. Fluoroless slow-pathway cryoablation showed a high efficacy and safety comparable to conventional fluoroscopy guided procedures.

Journal of Interventional Cardiology, 2012

Background: Total cavopulmonary connection (TCPC) is performed in patients having a single ventri... more Background: Total cavopulmonary connection (TCPC) is performed in patients having a single ventricle to allow the passive flow of systemic venous blood to the lungs. Interventional catheterization is needed to treat residual defects or complications. Aims: We discuss our results concerning 68 patients who had had TCPC from January 1995 to December 2010. Methods: Initial and follow-up catheterization data were reviewed retrospectively. Mid-term results were evaluated by means of angiography and/or CT scan. Results: Mean age at TCPC was 5 years (2.5-18); mean interval between TCPC and catheterization was 5.6 years (1.5-15). Sixty-nine catheterizations were performed in 53 patients. Eleven patients (21%) had low venous pressure, did not display a right-to-left shunt, and did not need any intervention. Fifteen patients (28%) had low venous pressure and only needed the closure of the fenestration. The remaining 27 patients (51%) needed the following interventions: embolization of venous vessels prompting right-to-left shunt (n , stenting or reconnection of pulmonary arteries (n = 5), stenting or recanalization of systemic veins (n = 11), other procedures (n = 5). In 3 patients the fenestration could not be closed due to high venous pressure. After the interventions oxygen saturation increased from 90.5% ± 4.8% to 94.7% ± 3.6% (P = 0.002). Conclusions: Our data show that 49% of patients with TCPC are in good condition late after surgery. However, half of these patients continue to need interventions generally aimed at suppressing stenoses at various levels of TCPC or at occluding vessels prompting right-to-left shunt. This population should enter a multicenter program aimed at identifying patients at risk. (J Interven Cardiol 2012; * * :1-6)

International Journal of Cardiology, 2014

Heart, 2011

Background Chronic right ventricular (RV) pacing is associated with deleterious effects on cardia... more Background Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function.

European Heart Journal, 2011

Europace, 2009

The aim of this study was to evaluate the feasibility and reliability of selective-site pacing by... more The aim of this study was to evaluate the feasibility and reliability of selective-site pacing by means of a new lead system in a paediatric population. This lead system is composed of a 4.1 Fr, active-fixation lead and a steerable catheter that allows easy positioning in selective sites. Thirty young patients (mean age 9.0 +/- 4.5 years, range 2-16 years) received a single- (10) or dual- (20) chamber pacemaker. The 3830 lead was implanted successfully in the targeted chambers in all patients. The selective RV sites of pacing in 26 of the patients were: 18 mid-septum, 5 outflow tract, 1 low-septum, and 2 LEVO-RV-Apex. In all patients, an intracardiac loop was left in order to avoid stretching of the lead with growth. Mean follow-up duration was 11 +/- 10 months. Atrial sensing and pacing thresholds were 3.2 +/- 1.7 mV and 0.8 +/- 0.6 V at 0.5 ms at implantation and 3.4 +/- 2.1 mV and 0.6 +/- 0.3 V at 0.5 ms at follow-up. Ventricular sensing and pacing thresholds were 12.1 +/- 4.9 and 0.7 +/- 0.4 V at 0.5 ms on implantation and 12.7 +/- 6.1 mV and 0.8 +/- 0.5 V at 0.5 ms at follow-up (P = NS). No adverse events were reported. Select Secure is a promising system for selective-site pacing in children.

Europace, 2011

region of interest. General statements about this point are definitely lacking in the paediatric ... more region of interest. General statements about this point are definitely lacking in the paediatric setting, therefore the operative strategy is mainly constrained by safety issues. We performed the ablation through the transseptal route in order to avoid the bulky effect of the catheter across the small aortic orifice which could have led to even fatal consequences, particularly in such compromised patient. Moreover as general believing the small size of the arterial structures and aortic root definitely increase the risk of vascular complications and limit manoeuvrability of the ablation catheter. 10,11 Conventional RF energy was employed instead of cryo, balancing the benefit of a more predictable and long-term-effective lesion against the risk of permanent and clinically relevant damage to the conduction tissue, that we estimated to be quite low.

Europace, 2010

In pacemaker patients with Gram-positive occult bacteremia, it is reasonable to remove the whole ... more In pacemaker patients with Gram-positive occult bacteremia, it is reasonable to remove the whole stimulation system, but therapeutic decision is sometimes very challenging. A young patient at 6 years of age underwent dual-chamber pacemaker implantation due to complete atrioventricular block after mitral valve replacement. He felt well until November 2008, when he suffered from febrile illness with blood cultures disclosing methicillin-resistant staphylococcus aureus strain. Repeated antibiotic courses were effective only in obtaining temporary remissions. Consecutive transoesophageal echocardiography examinations were inconclusive. A labelled leucocyte scintigraphy, showing increased captation along leads, was very helpful and critical in guiding our decision to extract leads. In equivocal cases, or when the hazard of extraction procedure is presumably high, every accessory diagnostic tool (like scintigraphy with labelled leucocytes) is helpful in establishing a definitive diagnosis and in strengthening a somewhat difficult decision.

Europace, 2010

Few data are available about selective-site pacing in children. A 4.1 Fr lead is now available: i... more Few data are available about selective-site pacing in children. A 4.1 Fr lead is now available: it has to be introduced through an 8.4 Fr steerable catheter, and it raises concerns as to the long-term patency of the subclavian vein. The aim of this study was to systematically evaluate the patency of the subclavian vein in children who had selective-site pacing by the SelectSecure Lead System (SSLS) for atrioventricular block and look for possible local early and late complications.

Circulation, 2013

We evaluated the effects of the site of ventricular pacing on left ventricular (LV) synchrony and... more We evaluated the effects of the site of ventricular pacing on left ventricular (LV) synchrony and function in children requiring permanent pacing. One hundred seventy-eight children (aged <18 years) from 21 centers with atrioventricular block and a structurally normal heart undergoing permanent pacing were studied cross-sectionally. Median age at evaluation was 11.2 (interquartile range, 6.3-15.0) years. Median pacing duration was 5.4 (interquartile range, 3.1-8.8) years. Pacing sites were the free wall of the right ventricular (RV) outflow tract (n=8), lateral RV (n=44), RV apex (n=61), RV septum (n=29), LV apex (n=12), LV midlateral wall (n=17), and LV base (n=7). LV synchrony, pump function, and contraction efficiency were significantly affected by pacing site and were superior in children paced at the LV apex/LV midlateral wall. LV dyssynchrony correlated inversely with LV ejection fraction (R=0.80, P=0.031). Pacing from the RV outflow tract/lateral RV predicted significantly decreased LV function (LV ejection fraction <45%; odds ratio, 10.72; confidence interval, 2.07-55.60; P=0.005), whereas LV apex/LV midlateral wall pacing was associated with preserved LV function (LV ejection fraction ≥55%; odds ratio, 8.26; confidence interval, 1.46-47.62; P=0.018). Presence of maternal autoantibodies, gender, age at implantation, duration of pacing, DDD mode, and QRS duration had no significant impact on LV ejection fraction. The site of ventricular pacing has a major impact on LV mechanical synchrony, efficiency, and pump function in children who require lifelong pacing. Of the sites studied, LV apex/LV midlateral wall pacing has the greatest potential to prevent pacing-induced reduction of cardiac pump function.

Circulation, 2009

The prevalence of genetic arrhythmogenic diseases is unknown. For the long QT syndrome (LQTS), fi... more The prevalence of genetic arrhythmogenic diseases is unknown. For the long QT syndrome (LQTS), figures ranging from 1:20,000 to 1:5,000 were published but none was based on actual data. Our objective was to define the prevalence of LQTS.

Catheterization and Cardiovascular Interventions, 2012

The objective of this study was to evaluate the technical feasibility, safety, and efficacy of th... more The objective of this study was to evaluate the technical feasibility, safety, and efficacy of the new device Amplatzer duct occluder II additional sizes (ADO II AS) for closure of patent ductus arteriosus (PDA). Transcatheter device closure is the standard care for PDA. Currently available technology is not designed for closure of small PDA in young children. From April to July 2011, seven children (five females, median age 1.5 years, median weight 11.4 kg) underwent PDA closure with the ADO II AS. Six had isolated PDA, one had PDA associated with preductal coarctation. We evaluated early and short-term results. All but one PDA was closed via an antegrade approach. Mean fluoroscopy and procedural times were 8.0 ± 3.9 and 49.8 ± 27.9 min, respectively. No complications occurred. Immediate trivial residual shunt was present in one patient. In all devices, the retention disks laid flat against the walls of the pulmonary artery and aorta, without protrusion into the vessel lumen. The echocardiography performed after 24 hr did not show any residual shunt. At a median follow-up of 2 months, the PDAs were completely occluded without obstruction of the pulmonary arteries or aorta. The new device ADO II AS was safely deployed with complete resolution of the PDA shunt. The lower profile and symmetry of this device allows for venous or arterial approach and smaller delivery catheter size. The ADO II AS might be a preferable alternative for closure of small-moderate PDAs.

Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology, 2021

Background. The long QT syndrome (LQTS), a leading cause of sudden death under 20 years of age, i... more Background. The long QT syndrome (LQTS), a leading cause of sudden death under 20 years of age, is due to mutations in genes which encode ion channels involved in the control of ventricular repolarization. In a prospective study on 34,000 neonates we found that a prolonged QT interval was associated with a 41 times greater risk for sudden infant death syndrome (SIDS) and, recently, in a case-control study on 201 cases of SIDS we found disease-causing LQTS mutations in 9.5% of the victims. Based on these results the Italian Ministry of Health is considering the possibility of introducing in the National Health Service an electrocardiographic (ECG) screening program in the first month of life to identify infants affected by LQTS. A realistic assessment of the prevalence of infants with LQTS becomes necessary. Methods. An ECG was recorded in the first month of life in 44,596 neonates. The QT interval was measured and corrected for heart rate according to the Bazett’s formula (QTc). In the neonates with a markedly prolonged QT (QTc ≥ 470 msec) molecular screening of the LQTS genes was performed. Results. A QTc between 440 and 470 msec was observed in 611 neonates (1.4%). A QTc ≥ 470 ms was found in 31 neonates (0.07%). Genetic analysis was performed in 28/31 (90%) neonates and LQTS mutations were identified in 14 of them (50%): 8 were LQT1, 4 LQT2 and 2 LQT3. Besides one de novo mutation, all other cases were familial and genetic analysis identified additional family members (37/72, 51%) affected by LQTS who had not been previously diagnosed. Within these 28 infants QTc was longer in the positively genotyped neonates (493±22 vs 479±6 ms, p=0.037) and a LQTS mutation was identified in all the neonates (n=5) with a QTc > 496 ms. Conclusions. An ECG performed in the first month of life, with genetic analysis in selected cases, allows early diagnosis of infants with sporadic and familial forms of LQTS, thus leading to institution of effective therapies aimed at preventing sudden death either in infancy or later on in life, not only in the neonates but also in their affected family members. This study also provides a first data-based estimate of LQTS prevalence, likely to be between 1/3,000 and 1/2,500 live births.

EuroIntervention, 2012

Limited data exists on midterm results concerning paediatric interventions on stenotic or occlude... more Limited data exists on midterm results concerning paediatric interventions on stenotic or occluded systemic veins following indwelling lines, cardiac surgery, or catheterisations. The purpose of this study was to report our acute and intermediate results concerning patients with (Group A) and without (Group B) congenital heart diseases (CHD) over a 10-year period. From January 2000 to December 2010, 32 patients (23 in Group A and nine in Group B, respectively) underwent 39 interventional catheterisations aimed to dilate or recanalise occluded iliofemoral veins, inferior or superior venae cavae. Initial and follow-up catheterisation data were reviewed retrospectively. Midterm results were evaluated by means of echography, angiography, and CT scan in all 15 and 17 patients, respectively. Median age and weight of all patients at catheterisation were five years (range 0.1-18) and 15 kg (range 2-60), respectively. Fifty-two stents were implanted in 29 patients (32 vessels). In 25 patients 28 vessels were occluded and required recanalisation. There were no major complications. In all but three patients it was possible to treat the lesion. There were two procedural complications (5.1%): one acute stent occlusion and one local dissection. At a median follow-up of 2.5 years (range 1-10) we observed six complications of stenting (11.5%): two fractures, two occlusions and two restenoses. Interventional catheterisation of stenotic or occluded systemic veins grants good immediate results at a low rate of complication. Stent dilatation or recanalisation may open the vessel for use during future procedures. However, long-term results are yet to be established.

Pacing and Clinical Electrophysiology, 2015

Background. Fluoroscopic catheter ablation of cardiac arrhythmias in pediatric patients exposes t... more Background. Fluoroscopic catheter ablation of cardiac arrhythmias in pediatric patients exposes the patients to the potential risk of radiation considering the sensitivity of this population and its longer life expectancy. We evaluated the feasibility, safety and efficacy of accessory pathway (AP) ablation guided by CARTO3 electroanatomic mapping (EAM) system with both cryoenergy and radiofrequency (RF) energy in order to avoid x-ray exposure in pediatric patients.

Pacing and Clinical Electrophysiology, 2013

Anatomical considerations and risks related to x-ray exposure make atrioventricular nodal reentra... more Anatomical considerations and risks related to x-ray exposure make atrioventricular nodal reentrant tachycardia (AVNRT) ablation in pediatric patients a concerning procedure. We aimed to evaluate the feasibility, safety, and efficacy of performing fluoroless slow-pathway cryoablation guided by the electroanatomic (EA) mapping in children and adolescents. Twenty-one consecutive patients (mean age 13.5 ± 2.4 years) symptomatic for AVNRT were prospectively enrolled to right atrium EA mapping and electrophysiological study prior to cryoablation. Cryoablation was guided by slow-pathway potential and performed using a 4-mm-tip catheter. Sustained slow-fast AVNRT was inducible in all the patients with a dual AV nodal physiology in 95%. Acute success was achieved in 100% of the patients with a median of two cryo-applications. Fluoroless ablation was feasible in 19 patients, while in two subjects 50 seconds and 45 seconds of x-ray were needed due to difficult progression of the catheters along the venous system. After a mean follow-up of 25 months, AVNRT recurred in five patients. All the recurrences were successfully treated with a second procedure. In three patients, a fluoroless cryoablation with a 6-mm-tip catheter was successfully performed, while in the remaining two patients, a single pulse of 60 seconds of radiofrequency energy was applied under fluoroscopic monitoring. No complications occurred. Combination of EA mapping systems and cryoablation may allow to perform fluoroless slow-pathway ablation for AVNRT in children and adolescents in the majority of patients. Fluoroless slow-pathway cryoablation showed a high efficacy and safety comparable to conventional fluoroscopy guided procedures.

Journal of Interventional Cardiology, 2012

Background: Total cavopulmonary connection (TCPC) is performed in patients having a single ventri... more Background: Total cavopulmonary connection (TCPC) is performed in patients having a single ventricle to allow the passive flow of systemic venous blood to the lungs. Interventional catheterization is needed to treat residual defects or complications. Aims: We discuss our results concerning 68 patients who had had TCPC from January 1995 to December 2010. Methods: Initial and follow-up catheterization data were reviewed retrospectively. Mid-term results were evaluated by means of angiography and/or CT scan. Results: Mean age at TCPC was 5 years (2.5-18); mean interval between TCPC and catheterization was 5.6 years (1.5-15). Sixty-nine catheterizations were performed in 53 patients. Eleven patients (21%) had low venous pressure, did not display a right-to-left shunt, and did not need any intervention. Fifteen patients (28%) had low venous pressure and only needed the closure of the fenestration. The remaining 27 patients (51%) needed the following interventions: embolization of venous vessels prompting right-to-left shunt (n , stenting or reconnection of pulmonary arteries (n = 5), stenting or recanalization of systemic veins (n = 11), other procedures (n = 5). In 3 patients the fenestration could not be closed due to high venous pressure. After the interventions oxygen saturation increased from 90.5% ± 4.8% to 94.7% ± 3.6% (P = 0.002). Conclusions: Our data show that 49% of patients with TCPC are in good condition late after surgery. However, half of these patients continue to need interventions generally aimed at suppressing stenoses at various levels of TCPC or at occluding vessels prompting right-to-left shunt. This population should enter a multicenter program aimed at identifying patients at risk. (J Interven Cardiol 2012; * * :1-6)

International Journal of Cardiology, 2014

Heart, 2011

Background Chronic right ventricular (RV) pacing is associated with deleterious effects on cardia... more Background Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function.

European Heart Journal, 2011

Europace, 2009

The aim of this study was to evaluate the feasibility and reliability of selective-site pacing by... more The aim of this study was to evaluate the feasibility and reliability of selective-site pacing by means of a new lead system in a paediatric population. This lead system is composed of a 4.1 Fr, active-fixation lead and a steerable catheter that allows easy positioning in selective sites. Thirty young patients (mean age 9.0 +/- 4.5 years, range 2-16 years) received a single- (10) or dual- (20) chamber pacemaker. The 3830 lead was implanted successfully in the targeted chambers in all patients. The selective RV sites of pacing in 26 of the patients were: 18 mid-septum, 5 outflow tract, 1 low-septum, and 2 LEVO-RV-Apex. In all patients, an intracardiac loop was left in order to avoid stretching of the lead with growth. Mean follow-up duration was 11 +/- 10 months. Atrial sensing and pacing thresholds were 3.2 +/- 1.7 mV and 0.8 +/- 0.6 V at 0.5 ms at implantation and 3.4 +/- 2.1 mV and 0.6 +/- 0.3 V at 0.5 ms at follow-up. Ventricular sensing and pacing thresholds were 12.1 +/- 4.9 and 0.7 +/- 0.4 V at 0.5 ms on implantation and 12.7 +/- 6.1 mV and 0.8 +/- 0.5 V at 0.5 ms at follow-up (P = NS). No adverse events were reported. Select Secure is a promising system for selective-site pacing in children.

Europace, 2011

region of interest. General statements about this point are definitely lacking in the paediatric ... more region of interest. General statements about this point are definitely lacking in the paediatric setting, therefore the operative strategy is mainly constrained by safety issues. We performed the ablation through the transseptal route in order to avoid the bulky effect of the catheter across the small aortic orifice which could have led to even fatal consequences, particularly in such compromised patient. Moreover as general believing the small size of the arterial structures and aortic root definitely increase the risk of vascular complications and limit manoeuvrability of the ablation catheter. 10,11 Conventional RF energy was employed instead of cryo, balancing the benefit of a more predictable and long-term-effective lesion against the risk of permanent and clinically relevant damage to the conduction tissue, that we estimated to be quite low.

Europace, 2010

In pacemaker patients with Gram-positive occult bacteremia, it is reasonable to remove the whole ... more In pacemaker patients with Gram-positive occult bacteremia, it is reasonable to remove the whole stimulation system, but therapeutic decision is sometimes very challenging. A young patient at 6 years of age underwent dual-chamber pacemaker implantation due to complete atrioventricular block after mitral valve replacement. He felt well until November 2008, when he suffered from febrile illness with blood cultures disclosing methicillin-resistant staphylococcus aureus strain. Repeated antibiotic courses were effective only in obtaining temporary remissions. Consecutive transoesophageal echocardiography examinations were inconclusive. A labelled leucocyte scintigraphy, showing increased captation along leads, was very helpful and critical in guiding our decision to extract leads. In equivocal cases, or when the hazard of extraction procedure is presumably high, every accessory diagnostic tool (like scintigraphy with labelled leucocytes) is helpful in establishing a definitive diagnosis and in strengthening a somewhat difficult decision.

Europace, 2010

Few data are available about selective-site pacing in children. A 4.1 Fr lead is now available: i... more Few data are available about selective-site pacing in children. A 4.1 Fr lead is now available: it has to be introduced through an 8.4 Fr steerable catheter, and it raises concerns as to the long-term patency of the subclavian vein. The aim of this study was to systematically evaluate the patency of the subclavian vein in children who had selective-site pacing by the SelectSecure Lead System (SSLS) for atrioventricular block and look for possible local early and late complications.

Circulation, 2013

We evaluated the effects of the site of ventricular pacing on left ventricular (LV) synchrony and... more We evaluated the effects of the site of ventricular pacing on left ventricular (LV) synchrony and function in children requiring permanent pacing. One hundred seventy-eight children (aged <18 years) from 21 centers with atrioventricular block and a structurally normal heart undergoing permanent pacing were studied cross-sectionally. Median age at evaluation was 11.2 (interquartile range, 6.3-15.0) years. Median pacing duration was 5.4 (interquartile range, 3.1-8.8) years. Pacing sites were the free wall of the right ventricular (RV) outflow tract (n=8), lateral RV (n=44), RV apex (n=61), RV septum (n=29), LV apex (n=12), LV midlateral wall (n=17), and LV base (n=7). LV synchrony, pump function, and contraction efficiency were significantly affected by pacing site and were superior in children paced at the LV apex/LV midlateral wall. LV dyssynchrony correlated inversely with LV ejection fraction (R=0.80, P=0.031). Pacing from the RV outflow tract/lateral RV predicted significantly decreased LV function (LV ejection fraction <45%; odds ratio, 10.72; confidence interval, 2.07-55.60; P=0.005), whereas LV apex/LV midlateral wall pacing was associated with preserved LV function (LV ejection fraction ≥55%; odds ratio, 8.26; confidence interval, 1.46-47.62; P=0.018). Presence of maternal autoantibodies, gender, age at implantation, duration of pacing, DDD mode, and QRS duration had no significant impact on LV ejection fraction. The site of ventricular pacing has a major impact on LV mechanical synchrony, efficiency, and pump function in children who require lifelong pacing. Of the sites studied, LV apex/LV midlateral wall pacing has the greatest potential to prevent pacing-induced reduction of cardiac pump function.

Circulation, 2009

The prevalence of genetic arrhythmogenic diseases is unknown. For the long QT syndrome (LQTS), fi... more The prevalence of genetic arrhythmogenic diseases is unknown. For the long QT syndrome (LQTS), figures ranging from 1:20,000 to 1:5,000 were published but none was based on actual data. Our objective was to define the prevalence of LQTS.

Catheterization and Cardiovascular Interventions, 2012

The objective of this study was to evaluate the technical feasibility, safety, and efficacy of th... more The objective of this study was to evaluate the technical feasibility, safety, and efficacy of the new device Amplatzer duct occluder II additional sizes (ADO II AS) for closure of patent ductus arteriosus (PDA). Transcatheter device closure is the standard care for PDA. Currently available technology is not designed for closure of small PDA in young children. From April to July 2011, seven children (five females, median age 1.5 years, median weight 11.4 kg) underwent PDA closure with the ADO II AS. Six had isolated PDA, one had PDA associated with preductal coarctation. We evaluated early and short-term results. All but one PDA was closed via an antegrade approach. Mean fluoroscopy and procedural times were 8.0 ± 3.9 and 49.8 ± 27.9 min, respectively. No complications occurred. Immediate trivial residual shunt was present in one patient. In all devices, the retention disks laid flat against the walls of the pulmonary artery and aorta, without protrusion into the vessel lumen. The echocardiography performed after 24 hr did not show any residual shunt. At a median follow-up of 2 months, the PDAs were completely occluded without obstruction of the pulmonary arteries or aorta. The new device ADO II AS was safely deployed with complete resolution of the PDA shunt. The lower profile and symmetry of this device allows for venous or arterial approach and smaller delivery catheter size. The ADO II AS might be a preferable alternative for closure of small-moderate PDAs.