Alessandra Marzi

Catheter ablation of ventricular arrhythmia in nonischemic cardiomyopathy: anteroseptal versus inferolateral scar sub-types.

Background—The aim was to relate distinct scar distributions found in nonischemic cardiomyopathy with ventricular tachycardia (VT) morphology, late potential distribution, ablation strategy, and outcome. Methods and Results—Eighty-seven patients underwent catheter ablation for drug-refractory VT. Based on endocardial unipolar voltage, 44 were classified as predominantly anteroseptal and 43 as inferolateral. Anteroseptal patients more frequently fulfilled diagnostic criteria for dilated cardiomyopathy (64% versus 36%), associated with more extensive endocardial unipolar scar (41 [22–83] versus 9 [1–29] cm2; P<0.001). Left inferior VT axis was predictive of anteroseptal scar (positive predictive value, 100%) and right superior axis for inferolateral (positive predictive value, 89%). Late potentials were infrequent in the anteroseptal group (11% versus 74%; P<0.001). Epicardial late potentials were common in the inferolateral group (81% versus 4%; P<0.001) and correlated with VT termination sites (&kgr;=0.667; P=0.014), whereas no anteroseptal patient had an epicardial VT termination (P<0.001). VT recurred in 44 patients (51%) during a median follow-up of 1.5 years. Anteroseptal scar was associated with higher VT recurrence (74% versus 25%; log-rank P<0.001) and redo procedure rates (59% versus 7%; log-rank P<0.001). After multivariable analysis, clinical predictors of VT recurrence were electrical storm (hazard ratio, 3.211; P=0.001) and New York Heart Association class (hazard ratio, 1.608; P=0.018); the only procedural predictor of VT recurrence was anteroseptal scar pattern (hazard ratio, 5.547; P<0.001). Conclusions—Unipolar low-voltage distribution in nonischemic cardiomyopathy allows categorization of scar pattern as inferolateral, often requiring epicardial ablation mainly based on late potentials, and anteroseptal, which frequently involves an intramural septal substrate, leading to a higher VT recurrence.Background— The aim was to relate distinct scar distributions found in nonischemic cardiomyopathy with ventricular tachycardia (VT) morphology, late potential distribution, ablation strategy, and outcome. Methods and Results— Eighty-seven patients underwent catheter ablation for drug-refractory VT. Based on endocardial unipolar voltage, 44 were classified as predominantly anteroseptal and 43 as inferolateral. Anteroseptal patients more frequently fulfilled diagnostic criteria for dilated cardiomyopathy (64% versus 36%), associated with more extensive endocardial unipolar scar (41 [22–83] versus 9 [1–29] cm2; P <0.001). Left inferior VT axis was predictive of anteroseptal scar (positive predictive value, 100%) and right superior axis for inferolateral (positive predictive value, 89%). Late potentials were infrequent in the anteroseptal group (11% versus 74%; P <0.001). Epicardial late potentials were common in the inferolateral group (81% versus 4%; P <0.001) and correlated with VT termination sites (κ=0.667; P =0.014), whereas no anteroseptal patient had an epicardial VT termination ( P <0.001). VT recurred in 44 patients (51%) during a median follow-up of 1.5 years. Anteroseptal scar was associated with higher VT recurrence (74% versus 25%; log-rank P <0.001) and redo procedure rates (59% versus 7%; log-rank P <0.001). After multivariable analysis, clinical predictors of VT recurrence were electrical storm (hazard ratio, 3.211; P =0.001) and New York Heart Association class (hazard ratio, 1.608; P =0.018); the only procedural predictor of VT recurrence was anteroseptal scar pattern (hazard ratio, 5.547; P <0.001). Conclusions— Unipolar low-voltage distribution in nonischemic cardiomyopathy allows categorization of scar pattern as inferolateral, often requiring epicardial ablation mainly based on late potentials, and anteroseptal, which frequently involves an intramural septal substrate, leading to a higher VT recurrence.

Noninducibility and Late Potential Abolition A Novel Combined Prognostic Procedural End Point for Catheter Ablation of Postinfarction Ventricular Tachycardia

Background— Successful late potential (LP) abolition and postprocedural ventricular tachycardia (VT) noninducibility constitute significant end points after catheter ablation for VT. We investigated the prognostic impact of a combined procedural end point of VT noninducibility and LP abolition in a large series of post–myocardial infarction patients with VT. Methods and Results— A total of 160 (154 men, 94% with implantable cardioverter defibrillators) consecutive post–myocardial infarction patients undergoing first-time ablation procedures from 2010 to 2012 were included. Of the 159 patients surviving the procedure, 137 (86%) were either inducible or in VT at baseline and 103 (65%) had baseline LP presence, of which 79 (77%) underwent successful LP abolition. The combined end point was assessable in 155 (97%) patients. There were 50 (32%) patients with VT recurrences and 17 (11%) cardiac deaths during follow-up. Patients who fulfilled the combined end point of VT noninducibility and LP abolition compared with inducible patients exhibited a significantly lower incidence of VT recurrence (16.4% versus 47.4%; log-rank P <0.001) and cardiac death (4.1% versus 42.1%; log-rank P <0.001). Among noninducible patients, those with additional LP abolition also had a lower incidence of VT recurrence (16.4% versus 46.0%; log-rank P <0.001). After multivariate analysis, the combined end point of VT noninducibility and LP abolition (hazard ratio, 0.205, P <0.001) was independently associated with VT recurrence and cardiac death (hazard ratio, 0.106; P =0.001). Conclusions— Achieving a combined catheter ablation procedural end point of VT noninducibility and LP abolition reduces VT recurrence rates to low levels (16%). The overall strategy was associated with a significant impact on cardiac survival.Background—Successful late potential (LP) abolition and postprocedural ventricular tachycardia (VT) noninducibility constitute significant end points after catheter ablation for VT. We investigated the prognostic impact of a combined procedural end point of VT noninducibility and LP abolition in a large series of post–myocardial infarction patients with VT. Methods and Results—A total of 160 (154 men, 94% with implantable cardioverter defibrillators) consecutive post–myocardial infarction patients undergoing first-time ablation procedures from 2010 to 2012 were included. Of the 159 patients surviving the procedure, 137 (86%) were either inducible or in VT at baseline and 103 (65%) had baseline LP presence, of which 79 (77%) underwent successful LP abolition. The combined end point was assessable in 155 (97%) patients. There were 50 (32%) patients with VT recurrences and 17 (11%) cardiac deaths during follow-up. Patients who fulfilled the combined end point of VT noninducibility and LP abolition compared with inducible patients exhibited a significantly lower incidence of VT recurrence (16.4% versus 47.4%; log-rank P<0.001) and cardiac death (4.1% versus 42.1%; log-rank P<0.001). Among noninducible patients, those with additional LP abolition also had a lower incidence of VT recurrence (16.4% versus 46.0%; log-rank P<0.001). After multivariate analysis, the combined end point of VT noninducibility and LP abolition (hazard ratio, 0.205, P<0.001) was independently associated with VT recurrence and cardiac death (hazard ratio, 0.106; P=0.001). Conclusions—Achieving a combined catheter ablation procedural end point of VT noninducibility and LP abolition reduces VT recurrence rates to low levels (16%). The overall strategy was associated with a significant impact on cardiac survival.

Electrical Storm Induced by Cardiac Resynchronization Therapy Is Determined by Pacing on Epicardial Scar and Can be Successfully Managed by Catheter Ablation

Background—The mechanism of cardiac resynchronization therapy (CRT)–induced proarrhythmia remains unknown. We postulated that pacing from a left ventricular (LV) lead positioned on epicardial scar can facilitate re-entrant ventricular tachycardia. The aim of this study was to investigate the relationship between CRT-induced proarrhythmia and LV lead location within scar. Methods and Results—Twenty-eight epicardial and 63 endocardial maps, obtained from 64 CRT patients undergoing ventricular tachycardia ablation, were analyzed. A positive LV lead/scar relationship, defined as a lead tip positioned on scar/border zone, was determined by overlaying fluoroscopic projections with LV electroanatomical maps. CRT-induced proarrhythmia occurred in 8 patients (12.5%). They all presented early with electrical storm (100% versus 39% of patients with no proarrhythmia; P<0.01), requiring temporary biventricular pacing discontinuation in half of cases. They more frequently presented with heart failure/cardiogenic shock (50% versus 7%; P<0.01), requiring intensive care management. Ventricular tachycardia was re-entrant in all. The LV lead location within epicardial scar was significantly more frequent in the proarrhythmia group (60% versus 9% P=0.03 on epicardial bipolar scar, 80% versus 17% P=0.02 on epicardial unipolar scar, and 80% versus 17% P=0.02 on any-epicardial scar). Ablation was performed within epicardial scar, close to the LV lead, and allowed CRT reactivation in all patients. Conclusions—CRT-induced proarrhythmia presented early with electrical storm and was associated with an LV lead positioning within epicardial scar. Catheter ablation allowed for resumption of biventricular stimulation in all patients.

Electroanatomical Voltage and Morphology Characteristics in Postinfarction Patients Undergoing Ventricular Tachycardia Ablation Pragmatic Approach Favoring Late Potentials Abolition

Background—Catheter ablation is an important therapeutic option in postmyocardial infarction patients with ventricular tachycardia (VT). We analyzed the endo–epicardial electroanatomical mapping (EAM) voltage and morphology characteristics, their association with clinical data and their prognostic value in a large cohort of postmyocardial infarction patients. Methods and Results—We performed total and segmental analysis of voltage (bipolar dense scar [DS] and low voltage areas, unipolar low voltage and penumbra areas) and morphology characteristics (presence of abnormal late potentials [LPs] and early potentials [EPs]) in 100 postmyocardial infarction patients undergoing electroanatomical mapping–based VT ablation (26 endo–epicardial procedures) from 2010–2012. All patients had unipolar low voltage areas, whereas 18% had no identifiable endocardial bipolar DS areas. Endocardial bipolar DS area >22.5 cm2 best predicted scar transmurality. Endo–epicardial LPs were recorded in 2/3 patients, more frequently in nonseptal myocardial segments and were abolished in 51%. Endocardial bipolar DS area >7 cm2 and endocardial bipolar scar density >0.35 predicted epicardial LPs. Isolated LPs are located mainly epicardially and EPs endocardially. As a primary strategy, LPs and VT-mapping ablation occurred in 48%, only VT-mapping ablation in 27%, only LPs ablation in 17%, and EPs ablation in 6%. Endocardial LP abolition was associated with reduced VT recurrence and increased unipolar penumbra area predicted cardiac death. Conclusions—Endocardial scar extension and density predict scar transmurality and endo–epicardial presence of LPs, although DS is not always identified in postmyocardial infarction patients. LPs, most frequently located in nonseptal myocardial segments, were abolished in 51% resulting in improved outcome.

Advanced techniques for chronic lead extraction: heading from the laser towards the evolution system

AIM The evolution mechanical dilator sheath has been reported to be an effective tool for chronic lead extraction (LE). We examined safety and efficacy of evolution system as compared with laser system. METHODS AND RESULTS From 2005 to 2009, all extractions requiring the use of a powered sheath were performed using the excimer laser system (n = 73). Since 2009, laser system was no longer available and the evolution system was introduced as the first-line method for powered extraction (n = 48). All procedures were performed by a single first operator. Success and complications were defined according to the current guidelines. Patients of the evolution group compared with those of the laser group had a greater number of extracted leads per patient (2.77 vs. 2.4, P = 0.049) and a longer implant duration (101.1 vs. 62.4 months, P = 0.001). Additional use of snare was required in 27.1% of the evolution group and 8.2% of the laser group (P = 0.005). Complete procedural success was achieved in 91.7% of the evolution group and 97.3% of the laser group (P = 0.16). There was also no difference between evolution and laser groups in clinical success (97.9 vs. 98.6%, P = 0.76), as well as regarding major (4.2 vs. 2.7%, P = 0.66) or minor complications (4.2 vs. 5.5%, P = 0.76). CONCLUSION Use of the recently introduced evolution system for LE exhibit acceptably high levels of safety, as well as of procedural and clinical success, although additional use of snare was required more frequently in the evolution compared with the laser group.

Left Atrial Appendage: Physiology, Pathology, and Role as a Therapeutic Target

Atrial fibrillation (AF) is the most common clinically relevant cardiac arrhythmia. AF poses patients at increased risk of thromboembolism, in particular ischemic stroke. The CHADS2 and CHA2DS2-VASc scores are useful in the assessment of thromboembolic risk in nonvalvular AF and are utilized in decision-making about treatment with oral anticoagulation (OAC). However, OAC is underutilized due to poor patient compliance and contraindications, especially major bleedings. The Virchow triad synthesizes the pathogenesis of thrombogenesis in AF: endocardial dysfunction, abnormal blood stasis, and altered hemostasis. This is especially prominent in the left atrial appendage (LAA), where the low flow reaches its minimum. The LAA is the remnant of the embryonic left atrium, with a complex and variable morphology predisposing to stasis, especially during AF. In patients with nonvalvular AF, 90% of thrombi are located in the LAA. So, left atrial appendage occlusion could be an interesting and effective procedure in thromboembolism prevention in AF. After exclusion of LAA as an embolic source, the remaining risk of thromboembolism does not longer justify the use of oral anticoagulants. Various surgical and catheter-based methods have been developed to exclude the LAA. This paper reviews the physiological and pathophysiological role of the LAA and catheter-based methods of LAA exclusion.

Predictors of Advanced Lead Extraction Based on a Systematic Stepwise Approach: Results from a High Volume Center

Lead extraction (LE) techniques have evolved from simple traction to extraction with dilators and powered sheaths with very high success rates. On the basis of the systematic implementation of a stepwise approach, we aimed to identify those characteristics that can predict the need for advanced LE techniques.

Safety and efficacy of the new bidirectional rotational Evolution® mechanical lead extraction sheath: results from a multicentre Italian registry

Aims The aim of this prospective multicentre study is to evaluate safety and efficacy of the new bidirectional rotational mechanical lead extraction (LE) sheath (Evolution RL, Cook Medical, USA) in chronically implanted leads (>1-year-old leads). Methods and results Between September 2013 and June 2016, a total of 238 leads in 124 consecutive patients were removed by using the new Evolution RL rotational mechanical sheath. Indications for LE were cardiac device infection in 63 (50.8%) cases, lead malfunction in 41 (33.1%), upgrade in 1 (0.8%) case and for other reasons in the remaining 19 cases (15.3%). Ninety-one leads (38.2%) were implantable cardioverter defibrillator leads (81 dual coil vs. 10 single coil), 38 (16%) right ventricular leads, 86 (36.1%) right atrial leads, and 23 (9.7%) coronary sinus leads. The mean implant duration was 92.2 ± 52.9 months (range 12-336). 91.6% of the leads (218/238) were extracted completely with the Evolution RL alone, with the complete success rate rising to 98.7% (235/238 leads) with combined use of a snare. Overall clinical success rate was 100%. No Evolution sheath-related complications were noted. There were no deaths or major complications. Five minor complications (4%) were encountered. In cases of companion leads no wrapping or lead damage were observed. Conclusion On the basis of our prospective multicentre study, the new hand-powered bidirectional rotational mechanical LE sheath is an effective and safe tool for the extraction of chronically implanted leads without major complications and lead wrapping or lead damage.

Left atrial appendage closure: A single center experience and comparison of two contemporary devices

To compare indications and clinical outcomes of two contemporary left atrial appendage (LAA) percutaneous closure systems in a “real‐world” population.

Catheter Ablation of Ventricular Arrhythmia in Non-Ischaemic Cardiomyopathy: Anteroseptal versus Inferolateral Scar Sub-Types

Background—The aim was to relate distinct scar distributions found in nonischemic cardiomyopathy with ventricular tachycardia (VT) morphology, late potential distribution, ablation strategy, and outcome. Methods and Results—Eighty-seven patients underwent catheter ablation for drug-refractory VT. Based on endocardial unipolar voltage, 44 were classified as predominantly anteroseptal and 43 as inferolateral. Anteroseptal patients more frequently fulfilled diagnostic criteria for dilated cardiomyopathy (64% versus 36%), associated with more extensive endocardial unipolar scar (41 [22–83] versus 9 [1–29] cm2; P<0.001). Left inferior VT axis was predictive of anteroseptal scar (positive predictive value, 100%) and right superior axis for inferolateral (positive predictive value, 89%). Late potentials were infrequent in the anteroseptal group (11% versus 74%; P<0.001). Epicardial late potentials were common in the inferolateral group (81% versus 4%; P<0.001) and correlated with VT termination sites (&kgr;=0.667; P=0.014), whereas no anteroseptal patient had an epicardial VT termination (P<0.001). VT recurred in 44 patients (51%) during a median follow-up of 1.5 years. Anteroseptal scar was associated with higher VT recurrence (74% versus 25%; log-rank P<0.001) and redo procedure rates (59% versus 7%; log-rank P<0.001). After multivariable analysis, clinical predictors of VT recurrence were electrical storm (hazard ratio, 3.211; P=0.001) and New York Heart Association class (hazard ratio, 1.608; P=0.018); the only procedural predictor of VT recurrence was anteroseptal scar pattern (hazard ratio, 5.547; P<0.001). Conclusions—Unipolar low-voltage distribution in nonischemic cardiomyopathy allows categorization of scar pattern as inferolateral, often requiring epicardial ablation mainly based on late potentials, and anteroseptal, which frequently involves an intramural septal substrate, leading to a higher VT recurrence.Background— The aim was to relate distinct scar distributions found in nonischemic cardiomyopathy with ventricular tachycardia (VT) morphology, late potential distribution, ablation strategy, and outcome. Methods and Results— Eighty-seven patients underwent catheter ablation for drug-refractory VT. Based on endocardial unipolar voltage, 44 were classified as predominantly anteroseptal and 43 as inferolateral. Anteroseptal patients more frequently fulfilled diagnostic criteria for dilated cardiomyopathy (64% versus 36%), associated with more extensive endocardial unipolar scar (41 [22–83] versus 9 [1–29] cm2; P <0.001). Left inferior VT axis was predictive of anteroseptal scar (positive predictive value, 100%) and right superior axis for inferolateral (positive predictive value, 89%). Late potentials were infrequent in the anteroseptal group (11% versus 74%; P <0.001). Epicardial late potentials were common in the inferolateral group (81% versus 4%; P <0.001) and correlated with VT termination sites (κ=0.667; P =0.014), whereas no anteroseptal patient had an epicardial VT termination ( P <0.001). VT recurred in 44 patients (51%) during a median follow-up of 1.5 years. Anteroseptal scar was associated with higher VT recurrence (74% versus 25%; log-rank P <0.001) and redo procedure rates (59% versus 7%; log-rank P <0.001). After multivariable analysis, clinical predictors of VT recurrence were electrical storm (hazard ratio, 3.211; P =0.001) and New York Heart Association class (hazard ratio, 1.608; P =0.018); the only procedural predictor of VT recurrence was anteroseptal scar pattern (hazard ratio, 5.547; P <0.001). Conclusions— Unipolar low-voltage distribution in nonischemic cardiomyopathy allows categorization of scar pattern as inferolateral, often requiring epicardial ablation mainly based on late potentials, and anteroseptal, which frequently involves an intramural septal substrate, leading to a higher VT recurrence.