Fluoroless cavotricuspid isthmus radiofrequency ablation of typical atrial flutter achieves success with zero radiation and shorter procedural duration

Funding Acknowledgements

Type of funding sources: None.

Background

Cavotricuspid isthmus (CTI) ablation in patients with typical atrial flutter (AFL) has improved in the past years, especially by the use of threedimensional (3D) electroanatomic mapping systems. These mapping tools contributed to reduce radiation exposure, but most ablation procedures still require varying amounts of fluoroscopy.

Purpose

We aim to examine whether fluoroless CTI ablation is effective and safe in reducing AFL recurrence, compared with CTI ablation using fluoroscopy and a 3D mapping system.

Methods

A retrospective analysis of CTI ablation procedures performed at a tertiary center between December 2008 and December 2020 was conducted. Cases were divided in two groups: fluoroless and fluoroscopic, according to the use of radiation. Procedural duration, fluoroscopy time (FT), use of 3D mapping system, complications and recurrence rate at one year were analyzed.

Results

A total of 324 CTI ablations performed on patients with documented typical AFL were included. Mean age was 62.3±14.0, with 78.1% male patients. Fluoroless ablations were performed based on a 3D mapping system, and all fluoroscopic procedures also used 3D electroanatomic mapping. The FT was zero in the fluoroless group - 31 cases (9.6%), and 7.0±4.4 minutes in the fluoroscopic group - 291 cases (90.4%) (p<0.001). There was no statistically significant difference between the two groups, regarding AFL recurrence at one year (21.7% in the fluoroless group versus 13% in the fluoroscopic group; odds ratio [OD] 0.54; 95% confidence interval [CI] 0.18-1.62; p=0.27). Total procedure duration was significantly shorter in the fluoroless group (1h07m versus 1h40m; t-test 4.261, p<0.001, CI 0h16m-0h50m). There were no acute complications for both groups.

Conclusion

Fluoroless CTI ablation avoids radiation exposure to the patient and operator and can be performed in patients with typical AFL, without compromising duration, safety or efficacy of the procedure.

Combined pulmonary vein isolation and cavotricuspid isthmus ablation shows no benefit in recurrence of atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Pulmonary vein isolation (PVI) is the mainstay of catheter ablation (CA) for atrial fibrillation (AF). Strategies have been proposed to improve the success rate of CA, such as prophylactic cavotricuspid isthmus (CTI) ablation. Despite some studies providing no, or limited, incremental benefit of CTI ablation in patients with AF, it is still frequently performed worldwide.

Purpose

The aim of this study is to examine whether CTI ablation, combined with PVI, is associated with improvement in recurrence of AF, compared with PVI alone in AF patients with or without atrial flutter (AFL).

Methods

We conducted a retrospective analysis of CA for AF performed at a tertiary center between September 2004 and December 2020. The procedures were divided in two groups: "PVI alone" and "PVI plus CTI ablation". Demographic, clinical, and procedure related data was retrieved. Atrial fibrillation recurrence rate at one year was analyzed for both groups and compared using logistic regression.

Results

A total of 453 procedures were analyzed: PVI alone (n=378; 83.4%) and PVI with CTI ablation (n=75; 16.6%). In the PVI alone group, 12.9% of the patients had concomitant typical AFL and in the PVI plus CTI ablation, 45.8% had typical AFL. Mean age was 57.3±12.1 years, with 63.6% male patients. At one year, AF recurrence rate was higher in the combined PVI with CTI ablation group (30.4%; n=21), compared with the PVI alone group (28.4%; n=97), with no statistical difference between the two groups (Odds Ratio [OD] 1.10; 95% confidence interval [CI] 0.62-1.94; p=0.73). In the subgroup analysis, there was no difference in recurrence between patients with AF without AFL (OR: 1.9; 95% CI: 0.39-9.36; p=0.43), and in patients with AF with concomitant AFL (OR: 10.0; 95% CI: 0.9-110.3; p=0.06).

Conclusion

In AF patients, irrespective of the presence of typical AFL, additional CTI ablation, compared with PVI alone, was not associated with improvement in recurrence of AF.

Long-term impact of activation circuit-based ventricular tachycardia ablation on ventricular arrhythmia burden

Funding Acknowledgements

Type of funding sources: None.

Background

Ventricular arrhythmias (VA) are a major cause of morbidity and mortality in heart failure patients. Ventricular tachycardia (VT) ablation is an established treatment for the reduction of recurrent implantable cardioverter-defibrillator (ICD) therapies in this population. In patients with substrate-related VT, mapping of the entire tachycardia circuit, when feasible, may allow for more accurate targeting of the clinical VT.

Purpose

To assess the long-term impact of catheter ablation based on activation mapping of substrate-related VT on VA burden.

Methods

Consecutive patients submitted to VT ablation between January 2013 and October 2021 were included. A comprehensive review of clinical records and device monitoring was performed to assess VA burden, defined as all ICD therapies and clinically documented VTs, before and after ablation. The primary outcome was reduction in the overall burden of VA after ablation. The impact of ablation on VA burden was assessed by fixed-effects Poisson regression; comparison at fixed time intervals was performed with a paired-sample Wilcoxon signed-rank test (STATA 12, JASP).

Results

A total of 134 VT ablation procedures were performed during the study period. Of these, there were 21 procedures where complete mapping of the VT activation circuit was achieved, corresponding to 18 patients. Mean age was 56.7 years, 88% male sex, mean left ventricular ejection fraction 39 ± 13%, BNP 540 ± 627 pg/mL. Etiology was ischemic in 44%, non-ischemic dilated cardiomyopathy in 39%, arrhythmogenic right ventricular dysplasia in 11% and hypertrophic cardiomyopathy in 6%. Mechanical support was in situ in 3 patients (two with temporary VA ECMO and one with LVAD as destination therapy); all but one patient had an ICD. Procedural duration was 209 ± 61 minutes. One patient developed complete AV block; no other peri-procedural complications were observed. During follow-up two patients died due to heart failure, one patient died from refractory cardiogenic shock with refractory incessant VT and one patient underwent orthotopic heart transplant. The mean follow-up time after ablation was 2.2 ± 1.9 years. A significant reduction in VA burden was observed (Figure 1) at 3 months (92.5% reduction, p=0.002) and 6 months after ablation (83.3% reduction, p=0.041). After fixed-effects Poisson regression, there was an estimated long-term reduction of 75% (CI 12-93%, p=0.031) of VA burden after VT circuit ablation.

Conclusion

Targeted circuit ablation is feasible in a subset of patients referred to VT ablation and leads to a significant sustained decrease in VA burden and device therapies.

Lead extraction with the "pisa technique" - experience of a portuguese tertiary care center

Funding Acknowledgements

Type of funding sources: None.

Background

The "Pisa Technique" (PT) is an increasingly used method of lead extraction (LE) that has shown excellent results in terms of clinical (Cs) and radiological success (Rs) associated with the lowest rate of complications reported in ELECTRa Registry.

Purpose

To characterize the adult population submitted to LE with the PT and evaluate its short-term results.

Methods

A single-center prospective study of consecutive procedures (P) of LE using the PT between February 2013 and October 2019. Demographic, clinical, and P related variables, mortality (M) and reimplantation (R) data were assessed.

Results

320 electrodes (E) were removed in a total of 171 Ps and 159 patients (pts). 80.7% of these P’s were due to CIED infection (55.1% due to pocket site infection, 18.8% to occult bacteremia with probable CIED infection and 26.1% due to both local and systemic infection, with 44% of pts presenting with valvular/ lead vegetation) and the remainder due to E dysfunction or venous occlusion. Pts averaged 67.7 years of age, 71.9% were male with a mean left ventricular ejection fraction of 47.8%.

19.3% presented coronary artery disease, 42.1% overt heart failure and 43.9% atrial fibrillation. 29 pts had cardiac resynchronization devices, 20 pts implantable cardioverter-defibrillator devices and 110 pts pacemaker systems (mostly DDD). The mean "age" of the extracted E’s was 83.2 months, 244 of which were atrial or ventricular pacing, 26 pacing E’s via the coronary sinus and 50 shock E’s. In 31.0% of the cases, the E’s were of active fixation, with 42.7% of the pts being pacing dependent. 14% of pts had a previous attempt of LE, 37.4% had already been submitted to generator replacement and a third to CIED upgrade. In 66.7% of pts, a new contralateral CIED was implanted during the hospital stay - H -(mean time for R of 6 days) and in 19% of R’s an antibacterial envelope was used. The Rs and Cs rates were 91.2% and 98.3%, respectively. There was 1 case of cardiac tamponade during LE, which was stabilized by pericardiocentesis and 2 pocket site hematomas requiring surgical drainage. There were no deaths during the P. During a mean follow-up (FU) of 33 months, 11 pts had to undergo a new P, 5 of them due to pocket reinfections. The M rate during FU was 24.2% (37 pts), with 8 pts (5.0%) dying during H, mostly due to septic shock, and 19 pts during the first year post-P.

Conclusion

Our center’s experience with the PT confirms the method’s high efficacy and safety in the percutaneous extraction of E’s in pts with CIED.

Impact of anticoagulation therapy on outcomes in patients undergoing transvenous lead extraction

Funding Acknowledgements

Type of funding sources: None.

Background

Oral anticoagulation (OAC) is essential for patients (pts) at high risk for thromboembolism. However,uninterrupted anticoagulation and bridging with enoxaparin increases the risk of pocket hematoma (PH) andinfection (I).

Aim

To evaluate the impact of OAC in the rate of PH and outcomes in pts undergoing lead extraction (LE) usingthe Pisa Technique (PT).

Methods

A single centre prospective study of consecutive procedures (Pr) of LE using the PT between February2013 and October 2019. Demographic, clinical, device and procedure related variables, morbidity and mortality(M) data were compared between pts without OAC (O0) and pts with AC (O1).

Results

320 electrodes (E) were removed in a total 171 Pr in 159 pts (mean age - 67.7 years, mean LVEF - 48%,male - 72%). The LE were from the following implanted systems: pacemaker – 110 pts, cardiac resynchronizationtherapy – 29 pts, cardioverter-defibrillator – 20 pts. The radiological success rate was 91.2% and the clinicalsuccess rate was 98.3%. There were 14 cases of PH. During a mean follow-up (FU) of 33 months, 11 pts had toundergo a new Pr, 5 of them due to pocket I. 8 pts (5.0%) died during hospital stay, and 19 pts during the firstyear post-Pr. There were no deaths during the Pr. O1 included 56 pts (35.4%), of which 51.9% were under vitaminK antagonists (AVK) and 48.1% under direct oral anticoagulants (DOAC). 11 pts were receiving OAC due toprosthetic mechanical valve, and the remainder due to atrial fibrillation (AF). Pts in O1 were significantly older(p=0.026), presented a lower LVEF (p=0.001), a higher prevalence of valvular heart disease - VHD -(p=0.002),overt heart failure (p=0.006), AF (p<0.001) and previous cardiac surgery - CS - (p<0.001). OAC was associatedwith a higher rate of PH (OR 2,44, IC 95% 1.02-5,84, p=0.046) and pts with PH presented a significantlyprolonged hospital stay (22.7 vs 9.8 days, p=0.031). These pts also presented a higher hospitalization rate duringthe first year post-Pr (OR 2,48, IC95% 1.27-4.88, p=0.009). There was no difference in all-cause hospital M(p=0.522), all-cause M during first year of follow-up (p=0.551) or need for reintervention (p=0.375). Among pts inO1, pts under AVK presented a significantly higher rate of PH (OR 18,67, IC95% 2,23-156,17, p=0.007).

Conclusion

Pts receiving OAC, particularly pts under AVK, presented a higher rate of PH after LE. PerioperativeOAC management is crucial to reduce the morbidity rate in this population.

Left atrial strain imaging and integrated backscatter: predictors of recurrence in patients with paroxysmal, persistent and long-standing persistent atrial fibrillation undergoing catheter ablation

Introduction

Left atrial (LA) strain imaging by echocardiography (TTE) is a promising tool in the evaluation of LA mechanical function. The aim of this study was to compare LA longitudinal strain and integrated backscatter (IBS) between paroxysmal (PAF), persistent (PersAF) and long-standing persistent AF (LsAF) and evaluate its association with AF recurrence post-index catheter ablation.

Methods

Analysis of consecutive patients (P) with symptomatic PAF and PersAF who underwent index AF catheter ablation and had performed TTE in our centre prior to AF ablation. LA reservoir phase longitudinal strain (LASr) and strain rate was assessed by 2D speckle-tracking at baseline. LA volume index (LAVi) and IBS were analysed. AF recurrence was documented with 12-lead ECG, 24h Holter monitoring, external loop recorder or pacemaker analysis in a 12-month follow-up period.

Results

78 P, 69% PAF vs 31% PersAF (46% LsAF), 65% male, 40% with structural heart disease, who underwent pulmonary vein isolation were studied (cryoballoon ablation in 53% and radiofrequency ablation in 47%). P with PersAF had a higher LAVi (46±15 mL/m2 vs 36±13 mL/m2 p=0.004), particularly LsAF P (55±17 mL/m2) and impaired LASr (9.2±4.9% vs 23.9±9.3%, p<0.001) (especially LsAF 5.61±3.08% vs 12.20±4.04%, p<0.001) as well as strain rate (0.58±0.25 s–1 vs 1.08±0.40 s–1, p<0.001). There was no significant difference between groups regarding IBS (116.6±36.1 dB vs 106.6±21.5 dB, p=0.134), including LsAF (128.8±21.5 dB vs 102.1±45.1 dB, p=0.071). During follow-up there was a 28% (22P) AF recurrence rate, higher in PersAF (50% vs PAF 20%, adjusted HR 3.44 [95% CI 1.44–7.69], p=0.005), particularly in LsAF (72% vs 31%, adjusted HR 3.24 [95% CI 0.98–10.9], p=0.048). P with AF recurrence showed significantly impaired baseline LASr both in PersAF (6.44±3.26% vs 11.93±4.79%, p=0.003), as well as PAF (13.86±5.65% vs 26.29±8.47%, p<0.001). LsAF P with AF recurrence demonstrated a considerably impaired LASr (4.99±2.93% vs 9.34±1.40%, p=0.006) vs PersAF. Multivariate analysis showed that impaired baseline LASr was an independent predictor of AF recurrence both in PersAF (adjusted HR 0.82 [95% CI 0.68–0.98], p=0.028) and PAF (adjusted HR 0.78 [95% CI 0.68–0.88], p<0.001). Kaplan-Meier analysis (Fig. 1) showed that both PAF and PersAF P with baseline LASr below the 18% cut-off had a significantly higher rate of AF recurrence, with earlier recurrence in PersAF. PAF P with AF recurrence had a higher baseline IBS (109.3±22.1 dB vs 94.7±14 dB, p=0.016) vs non-recurring P, in contrast to PersAF P (117.8±31.1 dB vs 115.4±42.1 dB, p=0.876), however IBS was not a significant predictor of AF recurrence in PAF (HR 1.03 [95% CI 0.99–1.07], p=0.060) or PersAF.

Conclusion

P with PersAF (and particularly LsAF) showed significantly impaired LASr, and PAF P with AF recurrence had superior baseline IBS vs non-recurring P. Reduced baseline LASr was an independent predictor of AF recurrence both in PAF and in PersAF P.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Familial hypercholesterolemia in acute coronary syndrome patients: underdiagnosis in female and in young patients

Introduction

Familial hypercholesterolemia (FH) is often underdiagnosed, particularly in female patients (P), even during hospital admission for acute coronary syndromes (ACS). The aim of this study was to apply the Dutch Lipid Clinic Network (DLCN) Criteria in P admitted for ACS and evaluate gender and age differences.

Methods

Prospective evaluation of P with ACS admitted to a tertiary center from 2005 to 2019. Data including family history and laboratory tests was analysed for the application of the DLCN criteria and results were stratified according to ACS subtype, gender and age groups (20–39, 40–59, 60–79 and ≥80 years [y]). P were followed up for 30 days for hospitalization, recurring ACS and mortality.

Results

3811 P were evaluated, mean age 63±13 years, 28% female and mean LDL cholesterol of 125±43 mg/dL. The admission diagnosis was unstable angina (UA) in 5%, non-ST-segment elevation myocardial infarction (NSTEMI) in 27% and ST-segment elevation MI (STEMI) in 68%.

Applying the DLCN criteria, 3089 P (81%) had a score of <3 (unlikely FH), 675P (17.7%) a score of 3 to 5 (possible FH), 41P (1.1%) a score of 6 to 8 (probable FH) and 1P (0.03%) a score of >8 (definite FH). Stratifying according to ACS type: among UA, 31P (16%) had possible FH and 4P (2.1%) had probable FH. Among NSTEMI, 145P (14.2%) had possible FH, 9P (0.9%) probable FH and 1P (0.03%) definite FH. Finally, among STEMI P, 497P (19.1%) had possible FH and 28P (1.1%) probable FH. Regarding female P, 158P (14.7%) had possible FH and 16 P (1.5%) probable FH. Among male P, 517P (18.9%) had possible FH and 25P (0.9%) probable FH (p=0.016 for interaction).

According to age groups, among P aged 20–39 y (136P), 61P (44.9%) had possible FH and 6P (4.4%) had probable FH. Concerning P aged 40–59 y (1766P), 575P (32.6%) had possible FH, 31 P (1.8%) probable FH and 1P (0.1%) definite FH. With regard to P aged 60–80 y (2122P), 80P (3.8%) had possible FH and 4P (0.2%) probable FH. Among P aged ≥80 y (1837P), only 9P (0.5%) had possible FH and no P had probable FH.

In a 30-day follow-up, there was an hospitalization rate of 3.5% (134P) and recurring ACS in 1.7% (65P), while the all-cause mortality was 2% (78P) and cardiovascular (CV) death was 1.3% (49P). Female P had a significantly lower hospitalization rate (1.8% vs 3.2%, p=0.003) as well as fewer recurring ACS (0.6% vs 1.7%, p=0.001). There was no significant gender difference regarding all-cause mortality (female 1.7% vs 1.5%, p=0.552) or CV death (0.8% vs 1.1%, p=0.323). The DLCN criteria score was significantly correlated with admission for recurring ACS (OR 1.19 [95% CI 1.04–1.36], p=0.04).

Conclusion

Application of the DLCN criteria in female P admitted for ACS revealed 158P (14.7%) with possible FH and 16P (1.5%) with probable FH. Regarding younger ACS P (20–39y), 44.9% had criteria for possible FH and 4.4% for probable FH, prompting us to do not overlook these P subgroups in daily practice and routinely assess the likelihood of FH.

Funding Acknowledgement

Type of funding sources: None.

Radiofrequency catheter ablation of focal atrial tachycardia: characteristics and results of a series in a tertiary hospital

Funding Acknowledgements

Type of funding sources: None.

Background

Focal atrial tachycardia (AT) is a relatively uncommon arrhythmia with poor response to medical treatment. Radiofrequency (RF) ablation appears to be a good option for treatment of symptomatic patients (P).

Purpose

To describe the clinical characteristics, electrophysiological (EP) findings, safety and short-term efficacy of catheter ablation in P with AT.

Methods

Retrospective analysis of consecutive P submitted to AT ablation using electroanatomical mapping between 2015 and 2020. If the AT was not present spontaneously, pacing maneuvers (atrial drive or burst pacing with up to 3 extra-stimuli) and isoprenaline was employed until reproducible induction of an ectopic atrial rhythm. Radiofrequency (RF) ablation was delivered at the site of earliest activation after validation of local electrograms until non-inducibility.

Results

A total of 46P (61% female) were included, with a mean age of 48 ± 23 years (minimum 8 months, maximum 86 years). Idiopathic AT was observed in 47,8%, while 52.2% had other relevant comorbidities (chronic pulmonary disease 17.4%; previous cardiac surgery 8,7%; congenital heart disease 10.9%; coronary artery disease 6.5%). Despite anti-arrhythmic therapy, daily palpitations were present in 87% of the cases and dizziness or syncope occurred in 22%). Nearly half (47.8%) had previously sought urgent medical care and 30.4% had a hospital admission due to arrhythmia. The clinical arrhythmia was documented in 34P (47.8% by 12-lead electrocardiography and 26.1% in 24h Holter monitoring). During the EP study a focal AT was documented in all P (spontaneously in 54.3% and induced with pacing maneuvers in 45.7%). AT origin after electroanatomical activation mapping is depicted in figure 1. After focal RF ablation, a second AT was induced in 16P (34.8%) and a new ablation was performed in 15 cases (93.8%). Total RF time was 508 ± 386 sec. One P developed right phrenic nerve palsy after ablation on the lateral wall of the right atrium. No other complications were noted. On follow-up (mean 320 ± 92 days), symptoms improved in 88.1% of the P, with a 3-fold decrease in urgent medical care visits and hospital admission for arrhythmia. Three P (8.7%) were submitted to a new EP study, in which an AT was documented and ablated in 2P.

Conclusion

AT is a very symptomatic arrhythmia, associated with increased usage of hospital resources and poor response to antiarrhythmic therapy. Ablation is an efficient treatment option, with a high success rate, low rate of complications and short-term clinical benefits. Abstract Figure. Distribution of focal atrial tachycardia

Left atrial strain imaging evaluation: a strong predictor of atrial fibrillation recurrence after single-procedure catheter ablation

Funding Acknowledgements

Type of funding sources: None.

Introduction

Identification of predictors of arrhythmia recurrence after catheter ablation of atrial fibrillation (AF) is a clinically relevant issue. Transthoracic echocardiography (TTE) is a readily accessible exam that can be useful in estimating left atrial (LA) mechanical function. The aim of this study was to evaluate LA structure and LA strain imaging at baseline and its association with AF recurrence after an index AF catheter ablation. Methods: Analysis of patients with symptomatic paroxysmal and persistent AF who underwent a single-procedure for AF ablation between 2015 and 2019 and had performed TTE in our centre prior to AF ablation. LA parameters were assessed by 2D speckle-tracking at baseline. LA diameter index (LAVi), LA ejection fraction, LA phasic strain: reservoir (LASr), conduit (LAScd) and contraction phases (LASct), as well as integrated backscatter (IBS) values were analysed. AF recurrence was documented with 12-lead ECG, 24h Holter monitoring, external loop recorder or pacemaker analysis during a 12-month follow-up period. Results: Of a total of 106 patients, 28 patients were excluded due to poor image quality. We studied 78 patients who underwent pulmonary veins isolation (PVI) (age 59 ± 14 years, 65% male, 40% with structural heart disease, 69% paroxysmal AF) with cryoballoon ablation in 53% and radiofrequency ablation in 47%. In a 12-month follow-up there was a 28% (22 patients) AF recurrence rate. Patients with AF recurrence had a baseline significantly superior LAVi (47 ± 17 mL/m2 vs. 36 ± 12 mL/m2, adjusted HR 1.04 [95% CI 1.01-1.06], p = 0.002) and lower estimated LA ejection fraction (25 ± 19.7% vs. 45.4 ± 21%, adjusted HR 0.96 [95% CI 0.94-0.98], p = 0.001). Multivariate analysis showed that baseline LA strain parameters were independent predictors of AF recurrence, as patients with AF recurrence showed impaired LASr (9.81 ± 5.79% vs 22.94 ± 9.98%, adjusted HR 0.81 [95% CI 0.73-0.89], p < 0.001) and LAScd (-6.74 ± 4.11% vs. -11.85 ± 7%, adjusted HR 1.11 [95% CI 1.03-1.19], p = 0.004). In patients in sinus rhythm during baseline TTE, LASct also correlated with AF recurrence, as patients with recurrence also showed impaired baseline LASct (-7.49 ± 3.65% vs -13.74 ± 5.4%, adjusted HR 1.39 [95% CI 1.11-1.75], p = 0.005). LASr <18% showed a sensitivity of 86% and specificity of 70% to predict AF recurrence. Kaplan-Meier curves (figure 1) showed that patients with LASr below the 18% cut-off had a significantly higher rate of AF recurrence. Baseline IBS did not reveal significant differences in AF recurrence (111.2 ± 23.9 dB vs. 105.9 ± 33.5 dB, HR 1.007 [0.993-1.002], p = 0.349). Conclusion: Baseline LA strain imaging parameters, including reservoir phase LA strain, were demonstrated to be independent predictors of AF recurrence after PVI. A LASr <18% showed good accuracy to predict AF recurrence. Abstract Figure. Kaplan-Meier curves - time to recurrence

Low-fluoro workflows and impact in radiation exposure in the electrophysiology lab

Funding Acknowledgements

Type of funding sources: None.

Background

 During electrophysiology (EP) procedures, fluoroscopy imaging is employed to visualise catheters position in real-time. However, ionizing radiation is a health hazard to both the patient and operator. In recent years, the use of electroanatomical mapping systems and operator adoption of low-fluoro workflows has allowed a reduction of radiation exposure. The aim of this study was to assess the evolution of fluoroscopy time (FT) in EP procedures, using conventional technique or an electroanatomical mapping system (EMS).

Methods

A retrospective analysis of consecutive EP procedures performed at a tertiary centre between September 2018 and October 2020 was conducted. The procedures were divided in 3 tertiles according to date (T1, T2 and T3), with T3 corresponding to the most recent interventions. Procedural duration, FT, use of EMS, radiofrequency time (RT), acute ablation success and procedural complications were examined.

Results

A total of 615 procedures were analysed: atrioventricular node reentry tachycardia (AVNRT) – n = 144, accessory pathways (AP) – n = 83, typical atrial flutter – n = 106, atrial fibrillation (AF) ablation with radiofrequency (RF) – n = 61, AF ablation with cryoballoon – n = 92, ablation of ventricular arrhythmias – n = 53, and 75 miscellaneous procedures (including atrioventricular node ablation, left atrial flutter ablation and cardioneuroablation). Mean age was 54.6 ± 18.2 years with 59.4% male sex patients. An EMS was used in 75% of the procedures, without significant differences between tertiles. A progressive reduction in median FT was observed over the tertiles (T1 6.3 min, interquartile range [IQR] 2.9-13.6; T2 5.4 min, IQR 2.1-12.0, and T3 3.1 min, IQR 1.2-7.2, Figure 1), and a statistical significant difference was found when comparing T1 to T3 (p < 0.001) and T2 to T3 (p < 0.001). The decrease in FT was observed throughout the study period for all different EP procedures (Figure 2). The number of procedures with zero fluoroscopy had gradually increased (T1 6.1%, T2 8.5% and T3 14.1%; T1 vs. T3 p <0.01). Younger patients (<20 years) were submitted to low fluoroscopy doses with a significant decrease over tertiles (T1 1.2 min, IQR 0.0-4.3; T2 0.9 min, IQR 0.0-2.5; T3 0.0, IQR 0.0-2.2, T1 vs.T3 p < 0.001). No significant difference in procedural duration, RT, acute procedural success or complication rate were noted between tertiles.

Conclusion

Reduction in radiation exposure can be achieved without compromising duration, safety and effectiveness of the procedure.  The commitment of operators to reduce radiation exposure using 3D mapping technology can lead to a significant decrease in the use of fluoroscopy. Abstract Figure. Fluoroscopic time analysis

Late gadolinium enhancement as a predictor of arrhythmias in patients with hypertrophic cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

Introduction

Patients with hypertrophic cardiomyopathy (HCM) are at increased risk of arrhythmias and sudden cardiac death (SCD). The Late gadolinium enhancement (LGE) in cardiovascular magnetic resonance (CMR) has been associated with the occurrence of arrhythmic events.

Purpose

The aim was to analyze the association between LGE burden and location and arrhythmic events in HCM patients (P).

Methods

Retrospective analysis of P with HCM in a single tertiary center. Baseline clinical, echocardiographic and CMR characteristics were collected. On follow up arrhythmias (ventricular fibrillation (VF), sustained ventricular tachycardia (SVT), non-sustained ventricular tachycardia (NSVT), paroxysmal supraventricular tachycardia (PSVT), atrial fibrillation (AF) and atrial flutter (AFL)) were identified. LGE on CMR was compared between patients with and without arrhythmias.

Results

61P (59% male) were included, with a mean age of 58 ± 2 years. The HCM risk-SCD score was 3.35 ± 0.28%. On echocardiography mean left ventricle ejection fraction was 62.16 ± 1.36% and maximum wall thickness 20.59 ± 0.596mm. 31.1% had systolic anterior movement of mitral valve and 26.7% had left ventricle outflow tract obstruction. LGE was present in 88.5% P with a median number of 5 ± 7 segments involved. Interventricular septum (IVS) was involved in 78.7% P, anterior wall

in 57.4%, inferior wall in 54.1%, lateral wall in 52.5%, posterior wall in 9.8%, basal segments in 62.3%, median segments in 68.9% and apical segments in 63.9%. On follow up 3.3%P died, 45.8% had hospitalizations (22,2% because of an arrhythmia) and 75% had arrhythmias (1.6% VF, 6.6% SVT, 50% NSVT, 9.8% PSVT, 37.7% AF and 6.6% AFL). The number of segments with LGE correlated with arrhythmias (p = 0.05 for arrhythmias, p = 0.03 for SVT, p = 0.008 for NSVT and p = 0.042 for PSVT). A cut off of 5 segments involved was a good predictor of arrhythmias (p = 0.002), NSVT (p= 0.006), PSVT (p = 0.024) and AF (p = 0.0029). For SVT the best cut off was 9 (p = 0.003). Considering the LGE location, we found an association between the segments involved and the occurrence of different arrhythmias (table 1).

Conclusion

Supraventricular and ventricular Arrhythmias are frequent in patients with HCM, with the most frequents being NSVT and AF. The LGE burden (>5 segments) and location (median inferior IVS, median anterior IVS, median anterior wall, basal anterior IVS, apical anterior wall, median inferior wall, apical anterior wall and basal inferior IVS) were correlated with arrhythmic events. Abstract Figure.

Predictors of atrial fibrillation occurrence in patients with hypertrophic cardiomyopathy

Introduction

Patients with hypertrophic cardiomyopathy (HCM) are at increased risk of dysrhythmias, especially atrial fibrillation (AF).

Purpose

The aim of this study was to evaluate the incidence of AF in HCM patients (P) and to determine predictors of AF.

Methods

Retrospective analysis of HCM P at a single tertiary center. Baseline clinical, echocardiographic and cardiovascular magnetic resonance (CMR) characteristics were collected. On follow up AF was identified by electrocardiogram and/or 24 hours Holter monitoring.

Results

61P (59% male) were included, with a mean age of 58±2 years. 27.9% had angina (all of them CCS 2), 34.4% were in NYHA II and 14.8% in NYHA III, 8.2% had syncope and 39.3% had palpitations. A family history of sudden cardiac death (SCD) or cardiomyopathy was present in 40.4% of the cases. The mean HCM risk SCD score was 3.35±0.28%. On echocardiography left atrium (LA) diameter was 44.86±0.87mm, LA volume (LAvol) was 89.97±5.39mL (indexed LAvol 46.05±2.55mL/m2), interventricular septum (IVS) was 16.83±0.663mm, left ventricle (LV) mass was 290.94±13.897g and maximum wall thickness (MWT) was 20.59±0.596mm. 77% P had LA enlargement. 88.5%P had late gadolinium enhancement (LGE) in CMR with a median number of 5±7 segments involved. AF developed in 23P (37.7%), with a mean age of 58±3 years. Predictors of AF development were NYHA III (p=0.007), risk score (p=0.007), LA diameter (p=0.007), LAvol (p=0.005) and indexed LAvol (p=0.002), MWT (p=0.0015), LGE in more than 5 segments (p=0.029) and LGE in the inferior basal and inferior median IVS (p=0.033 and p=0.042). The only independent predictor was LAvol (p=0.0012), with an area under the curve of 0.755 and a cut off of 85.9mL being the best predictor (p=0.004). Combining LAvol >85.9mL with LGE involving >5 segments and LAvol >85.9mL with LGE in inferior basal IVS (IBIVS) a statistically significant difference between groups was achieved (p=0.009 in the combined predictor LAvol + LGE >5 segments and p=0.002 in the combined predictor LAvol + LGE in IBIVS) (figure 1 and figure 2). In a multivariable analysis including these 2 combined predictors and LAvol alone the only independent predictor was the combination of LAvol + IBIVS involvement.

Conclusion

AF is frequent in patients with HCM and develops in younger ages than in general population. NYHA III, risk score, LA diameter, LAvol, MWT, LGE >5 segments and LGE in IBIVS and in IMIVS were predictors of AF, with LAvol being the independent predictor. The combination of LAvol with LGE >5 segments and LAvol with LGE in IBIVS presented stronger predictor value comparing with these characteristics alone.

Funding Acknowledgement

Type of funding source: None

Performance of the padit score in patients undergoing transvenous lead extraction

Background

The PADIT trial identified 5 independent predictors of cardiac implantable electronic device (CIED) infection (prior procedure, age, chronic kidney disease, immunosuppression and type of procedure) and developed a novel infection risk score.

Aim

To assess whether the PADIT score (PS) could predict CIED reinfection and adverse events in patients (pts) submitted to transvenous lead extraction (LE) using the Pisa Technique (PT) due to CIED infection.

Methods

We conducted a single-centre prospective study of consecutive procedures (P) of LE using the PT between February 2013 and October 2019. Demographic, clinical, microbiological, device/ procedure related variables, morbidity and mortality data were retrieved during follow-up (FUP). An univariate analysis was performed to evaluate the ability of the PS to predict CIED reinfection (Re), procedural complications (C), all-cause hospital mortality (M), all-cause mortality/ hospitalization during first year of follow-up (MH1) and cardiovascular mortality (CM).

Results

A total 171 Ps including 159 pts, of which 80.7% (130 pts)were due to CIED infection: 55.1% due to pocket site infection, 18.8% to occult bacteremia with probable CIED infection and 26.1% due to both pocket site and systemic infection, with 44% of pts presenting with valvular/ lead vegetation (mean age - 70.3Y, 77.7% male, mean LVEF of 49.6%). The Rs rate was 93.1% and the clinical success rate was 99.2%. There were no deaths related to the procedure. During a mean FUP of 33 months, 11 pts had to undergo a new P, 5 of them due to pocket reinfection. The mortality rate was 24.2% (37 pts), with 8 pts dying during hospital stay, and 19 pts during the first year post-P. The mean PS was 2.9±2.5 (min- 0, max- 10). A higher PS value was associated with Re (HR - 1,43, CI95% 1.09–1.87, p=0.011), CM (HR - 1,39, CI95% 1.06–1.85, p=0.018) and MH1 (OR - 1,19, CI95% 1.03–1.38, p=0.021). There was no association between the PS and the rate of clinical success of the procedure (2.9% vs 4.5%, p=0.395), procedural complications (2.9% vs 3.3%, p=0.656) and M (4.0% vs 2.8%, p=0.192). Interestingly, a higher PS was not associated with a higher use of an antibacterial envelope during device reimplantation (3.5% vs 2.9%, p=0.371).

Conclusion

The PADIT score revealed a high predictive power for reinfection, all-cause mortality/ hospitalization during first year of follow-up and cardiovascular mortality in pts submitted to LE using the PT for CIED infection.

Funding Acknowledgement

Type of funding source: None

New onset atrial fibrillation after dual chamber pacemaker implantation: long term predictors

Background

Preserving atrioventricular synchrony has been accepted as a significant advantage of atrial and dual-chamber (DDD) pacing. However, little is known about the incidence of atrial fibrillation (AF) after DDD implantation and its prognostic predictors in long term.

Purpose

To determine the incidence of new AF episodes and to identify risk factors and prognostic predictors for new-onset AF and all-cause mortality after implantation of dual-chamber pacemakers.

Population and methods

713 consecutive patients (P) who underwent colocation of DDD pacemaker, due to AV block (AVB) or sinus node disease (SND), with no prior history of AF, from 2011 to 2015. Through periodic PM interrogation, occurrence of AF (“automatic mode switch” episodes with documented AF), switch to ventricular pacing (VVIR), pacing site (apical or septal) and cumulative right ventricular (RV) pacing % were analysed.

Results

Follow-up data was available for 669 patients (93.8%) for a mean follow-up (FU) time of 47.8±22.7 months. Mean age was 72.9±10.8 years with 60.1% male. New occurrence of AF was observed in 345 P (51.6%) during the FU period; 45.7% of them were consequently anticoagulated (59.0% with NOACs). Median time to 1st AF episode since implantation was 21.6 months and in 50.9% of the cases it lasted ≥1h. In univariate analysis, 1st AF episode lasting more than 1 hour and existence of at least one episode longer than 24 hours were directly related to switch to VVIR (p<0.0005; p<0.0005; p<0.0005) as well as prescription of anticoagulation (p=0.001; p=0.011; p<0.0005).

Compared to non-AF P, those with AF were older (74.0±9.9 vs. 71.8±11.7 years; p=0.008), had higher prevalence of SND (50.0% vs 40.20%; p=0.015), had superior % of RV pacing (65.9±39.3% vs. 58.3±44.3%; p=0.021) and more frequently had RV apical pacing (70.1% vs 57.3%; p=0.001). The prevalence of hypertension, diabetes mellitus and dyslipidemia were similar in the two groups. With multivariable Cox-regression, age (HR 1.02; p=0.017), SND (HR 1.49; p=0.010), admission for HF (HR 1.55; p=0.012) and % RV pacing (HR 1.01; p=0.003) were significantly associated with the incidence of FA. Predictors of all-cause mortality in Cox regression were the occurrence of AF in 1st of FU (HR 1.67; p=0.018) and % RV pacing (HR 1.01; p=0.043).

Conclusions

New onset AF is a frequent finding after DDD pacemaker implantation and is associated with all-cause mortality in long term. Age, admission for heart failure, sinus node disease and % of RV pacing were independent predictors for AF during follow-up.

Funding Acknowledgement

Type of funding source: None

External validation of a heart failure risk prediction model in a remote monitoring cohort submitted to cardiac resynchronization therapy

Background

Patients (P) submitted to cardiac ressynchronization therapy (CRT) are at high risk of heart failure (HF) events during follow-up. Continuous analysis of various physiological parameters, as reported by remote monitoring (RM), can contribute to point out incident HF admissions. Tailored evaluation, including multi-parameter modelling, may further increase the accuracy of such algorithms.

Purpose

Independent external validation of a commercially available algorithm (“Heart Failure Risk Status” HFRS, Medtronic, MN USA) in a cohort submitted to CRT implantation in a tertiary center.

Methods

Consecutive P submitted to CRT implantation between January 2013 and September 2019 who had regular RM transmissions were included. The HFRS algorithm includes OptiVol (Medtronic Plc., MN, USA), patient activity, night heart rate (NHR), heart rate variability (HRV), percentage of CRT pacing, atrial tachycardia/atrial fibrillation (AT/AF) burden, ventricular rate during AT/AF (VRAF), and detected arrhythmia episodes/therapy delivered. P were classified as low, medium or high risk. Hospital admissions were systematically assessed by use of a national database (“Plataforma de Dados de Saúde”). Accuracy of the HFRS algorithm was evaluated by random effects logistic regression for the outcome of unplanned hospital admission for HF in the 30 days following each transmission episode.

Results

1108 transmissions of 35 CRT P, corresponding to 94 patient-years were assessed. Mean follow-up was 2.7 yrs. At implant, age was 67.6±9.8 yrs, left ventricular ejection fraction 28±7.8%, BNP 156.6±292.8 and NYHA class >II in 46% of the P. Hospital admissions for HF were observed within 30 days in 9 transmissions. Stepwise increase in HFRS was significantly associated with higher risk of HF admission (odds ratio 12.7, CI 3.2–51.5). HFRS had good discrimination for HF events with receiving-operator curve AUC 0.812.

Conclusions

HFRS was significantly associated with incident HF admissions in a high-risk cohort. Prospective use of this algorithm may help guide HF therapy in CRT recipients.

Funding Acknowledgement

Type of funding source: None

P1377Substrate-based ablation in patients with frequent appropriate ICD therapy and dilated cardiomyopathy: long-term experience with high-density mapping

Recurrent ventricular tachydisrhythmias (VT) episodes have a negative impact in the outcome of patients (P) already with an implantable cardioverter-defibrillator (ICD). Elimination of arrhythmic reentry circuits represents a difficult challenge, mainly due to the induction of intolerable VTs, with multiple ECG morphologies, requiring rapid interruption. Substrate guided ablation has been used as a promising approach strategy to treat recurrent VTs. Aim: to assess long-term results of a VT substrate-based ablation using high-density mapping in P with an ICD, severe left ventricular (LV)  dysfunction and recurrent appropriate ICD therapy. Methods: 16P (12 men, non-ischemic cardiomyopathy 67%, 55 ± 13 years, LV ejection fraction 32 ± 6%) and recurrent appropriate shocks despite antiarrhythmic drug therapy and optimal heart failure medication. All P underwent a protocol of ventricular programmed stimulation (600 ms/S3) to obtain baseline VT documentation. A sinus rhythm (SR) voltage map was created using a 3D electroanatomic mapping system (CARTO) with a high-density mapping catheter (PentaRay) to delineate areas of scarred myocardium (ventricular bipolar voltage ≤0,5 mV – dense scar; 0,5-1,5 mV – border zone; ≥1,5 mV – healthy tissue) and provide high-resolution electrophysiological mapping. The substrate modification included catheter elimination of local abnormal ventricular activities (LAVA) - fractionated, splited, low-amplitude/long-lasting, late potentials, pre-systolic potentials - and linear ablation to obtain scars homogenization and scar dechanneling. Pace-mapping techniques were used when capture was possible. LV approach was retrograde in 6 cases, transeptal in 4 and endo-epicardial in 2 cases. In 2P the ablation was performed in the right ventricle. Results: VTs were induced and interrupted with bursts or external DC shocks. LAVA were identified and ablated in all P. Eleven P underwent modification of scar areas. The mean duration of the procedure was 153 mn (103-218 mn), with radiofrequency ranging from 18 to 60 mn (mean 33 min), and a mean fluoroscopy time of 16 mn. Non-inducibility was achieved in 75% of the cases. There was 1 pericardial tamponade drained successfully. During a follow-up of 48 ± 18 months, 75% had no VT recurrences, 2P underwent redo ablation, 1P died from stroke. Conclusion: Catheter ablation of VT based on substrate modification guided by high-density mapping is feasible and safe in P with LV dysfunction. This approach may be of clinical relevance, with potential benefits in reducing VT burden.

P1136Is there a negative impact of permanent pacemaker implantation in long-term outcomes after transcatheter aortic valve implantation?

Introduction

Transcatheter aortic valve implantation (TAVI) is an established treatment in patients (P) with aortic stenosis. Despite the continuous developments of this procedure, high-grade conduction disturbances requiring permanent pacemaker (PPM) implantation is still a major and common complication of TAVI. Furthermore, long-term chronic right ventricular pacing has been associated with negative effects on ventricular function and heart failure (HF).

Aim

  to evaluate the long-term impact of PPM after TAVI focusing on mortality and HF hospitalization.

Methods

 We retrospectively examined P who underwent TAVI with a self-expanding valve from 2009 to 2018 at our institution. All P had pre-procedural clinical evaluation, including ECG, cardiac computed tomographic angiography and transthoracic echocardiography. P with previous PPM were excluded.

Results

 265P (57% male, mean age 81.4 years, 20% with left ventricular ejection fraction <40%) were analysed. Mean STS score and mean Euroscore II were 6.33% and 7.07%, respectively. Mean transvalvular gradient was 52.78 mmHg and mean aortic valve area 0.67 cm2. Forty-seven P (17%) underwent PPM implantation during the first 30 days after TAVI. P requiring PPM had higher prevalence of diabetes mellitus, chronic renal disease, atrial fibrillation and right bundle branch block. During a mean follow-up of 20.3 months, post-TAVI PPM was associated with similar mortality rate (29.8% vs. 25.6%, HR 1.28, 95% CI 0.72-2.29, p = 0.42) and similar cardiovascular mortality (9.8% vs. 6.4%, HR 0.72, 95% CI 0.21-2.4, p = 0.59) compared to P without PPM. There were no significant differences in HF hospitalization (4.9% vs. 2.4%, p = 0.47). Kaplan-Meier curves of total mortality and cardiovascular mortality according to the need for PPM post-TAVI were similar. 

Conclusions

 In P submitted to TAVI, PPM implantation is a relatively common finding, not associated with higher risk of total mortality, cardiovascular mortality or HF hospitalization in a long-term follow-up.

1185 Three-dimensional speckle tracking echocardiography for the global and regional assessment of myocardial deformation in breast cancer patients submitted to anthracyclines

Introduction

Serial echocardiographic assessment of 2D/3D left ventricular ejection fraction (LVEF) and 2D global longitudinal strain (GLS) is the gold standard for screening for cancer therapeutics-related cardiac dysfunction (CTRCD). Although 3D speckle tracking echocardiography (STE) has several technical advantages, is more reproducible, and has a better correlation to magnetic resonance than 2D STE, it is still not currently used in this setting. We aimed to investigate the usefulness of 3D STE in evaluating left ventricle mechanics and its relation to CTRCD.

Methods

Prospective study of female breast cancer patients submitted to anthracycline chemotherapy who underwent one transthoracic echocardiography (ETT) before and at least one ETT during/after chemotherapy. Standard ETT parameters and 3D volumetric measurements were assessed. STE was used to estimate 2D GLS – average and 18 segments – and 3D GLS, global circumferential strain (GCS), global radial strain (GRS) and global area strain (GAS) – average and 17 segments. CTRCD was defined as an absolute decrease in 2D or 3D LVEF >10% to a value <54% or a relative decrease in 2D GLS >15%.

Results

105 patients (mean age 53.8 ± 12.5 years, 52.4% immunotherapy, 77.2% radiotherapy, 2.8 echocardiograms/patient) were included. During a mean follow-up of 12.1 months, 24 patients (22.9%) developed CTRCD. During anthracycline therapy, there was a significant worsening of 2D LVEF (65.6 vs. 57.8), 3D LVEF (61.5 vs. 54.4), 2D GLS (-21.1 vs. -18.0), 3D GLS (-15.6 vs. -10.9), 3D GCS (-14.0 vs. -11.0), 3D GRS (42.0 vs. 28.5) and 3D GAS (-27.0 vs. -20.0) [all p <0.001]. More than 73% of patients presented 3D global strain values below the limits of normal during chemotherapy. On 3D strain regional analysis, impaired contractility was observed in the anterior, inferior and septal walls. Logistic regression analysis showed that 3D GRS and 3D GCS were associated with a higher incidence of CTRCD. In the multivariate model, 3D GRS remained the only independent predictor of CTRCD. The receiver operating curve analysis showed a good calibration and discrimination of 3D GCS and 3D GRS in predicting CTRCD with areas under de curve of 0.748 and 0.719, with the optimal cut-off values being 0.342 for GCS and 0.344 for GRS. These variations were observed a median of 45 days and 22.5 days before the diagnosis of CTRCD, respectively.

Conclusion

3D strain parameters worsened during anthracycline therapy, with predominant involvement of septal, anterior and inferior walls. Variations of 3D GCS and GRS were predictive of subsequent CTRCD, and thus can be considered an earlier sign of CTRCD, with added value over the currently recommended 2D/3D LVEF and 2D GLS. Routine application of this technique should be considered in order to offer targeted monitoring and timely initiation of cardioprotective treatment.

P672 Predictors of ventricular arrythmias and mortality after implantation of primary prevention antitachycardia devices

Background

Patients (pts) with reduced left ventricular (LV) systolic function have high risk of sudden cardiac death and benefit from implantable cardioverter-defibrillators (ICDs/CRT-Ds). However, the risk for arrhythmic events and device therapies is extremely heterogeneous in this population, so more accurate tools for risk stratification are required.

Purpose

To assess predictors of mortality and arrhythmic events in pts receiving primary prevention ICDs/ CRTs.

Methods

Retrospective analysis of 150 pts submitted to primary prevention ICD/ CRT-D implantation with remote monitoring between 2014-2018. Demographic, clinical and echocardiographic data from implantation and follow-up period were retrieved. Arrhythmic events and device therapies were retrieved from remote monitoring and clinic visits. Univariate analysis was performed followed by a multivariate Cox analysis to evaluate predictors of events. p < 0.05 were considered significant.

Results

150 pts, 80.7% male, with a mean age of 64.30 ± 12.9 years (Y) and a mean follow-up (FU) time of 38 ± 15 months. 66% of pts implanted an ICD. 52.0% of pts presented with an ischemic cardiomyopathy and 41.3% had atrial fibrillation. 35.3% had chronic kidney disease (GFR < 60mL/min) and 24.0% were diabetic. Mean BNP value of 449.6 ± 631.3pg/mL and mean peak VO2 of 15.3mL/kg/min. Mean LV ejection fraction (LVEF) during FU of 35.9 ± 12.1% and a mean average global longitudinal strain (GLS) of -8.7 ± 5.5%. 63pts (42.0%) suffered a ventricular arrhythmia, mostly non-sustained ventricular tachycardia, of which 47.6% received appropriate therapies. Mortality rate of 13.3% during follow-up (20 pts). Baseline diabetes (p = 0.040) and post-procedural pulmonary artery systolic pressure (PASP) (p = 0.002) were independent predictors of overall mortality in the follow-up. Male gender (p = 0.041), baseline diabetes (p = 0.011) and atrial fibrillation (p = 0.038) were associated with ventricular events. In patients with CRT-D, a percentage of biventricular pacing superior to 95% was found to be protective against ventricular arrhythmias. Interestingly despite being associated with a higher overall mortality (p = 0.028), a reduced LVEF wasn’t related to the arrhythmic burden of our population, neither the GLS nor the LV mechanical dispersion were predictors of ventricular arrhythmias.

Conclusion

Baseline diabetes and PASP were independent predictors of mortality in our population of ICD/CRT-D pts implanted in primary prevention setting. An increased percentage of biventricular pacing was associated to improved clinical outcomes in patients receiving cardiac resynchronization therapy. Identification of predictors of events in this population can help individualize its management.

P1256 Salvage mitraclip implantation for postmyocardial infarction mitral regurgitation: 2 case reports

Introduction

Acute mitral regurgitation (MR) secondary to AMI is associated with a poor clinical outcome. The role of MitraClip implantation (MCI) in this population is still not well established. We report two successful cases of salvage MCI in acute ischaemic MR.

Case Report 1: A 66-year-old diabetic woman was admitted to our institution due to extensive anterior STEMI with cardiogenic shock. Urgent cardiac catheterization (CC) revealed 100% occlusion of the left anterior descending and critical stenosis of the obtuse marginal artery, with successful PCI of both vessels and implantation of an intra-aortic balloon pump. Early transthoracic echocardiogram (TTE) revealed a dilated left ventricle with severe systolic dysfunction (LVEF – 35%), apical and anterior wall akinesia and functional grade IV MR (EROA - 40mm2 and regurgitant volume - 45mL), that was later confirmed by transesophageal echocardiography (TEE). 48h after AMI, the patient developed an arrhythmic storm requiring multiple shocks and a prolonged period of mechanical ventilation. Due to an extremely slow clinical improvement, with the need for prolonged inotropic support and refractory pulmonary congestion (NYHA IV), she was submitted to MCI, resulting in post-procedural grade I MR (EROA 7mm2 and regurgitant volume 11mL) and a marked clinical and hemodynamic improvement. An ICD for secondary prevention was implanted. At the 3 month follow-up the patient presented in NYHA II functional class without congestive symptoms.

Case Report 2: An 82-year old female patient was admitted with an inferior STEMI, with CC documenting severe 3 vessel disease with a calcified occlusion of the right coronary artery, not amenable to PCI, so the patient was submitted to emergent CABG. There was a prolonged period of post-operatory mechanical ventilation with an extremely difficult weaning process, including the need for re-intubation due to acute pulmonary edema. TTE revealed LVEF of 39% with a large inferobasal aneurysm and severe eccentric MR due to tendinous cord rupture. The patient was submitted to MCI with immediate significant improvement of the MR, allowing successful extubation 36 hours after the procedure. In the end of first month of follow-up, the TTE revealed a well-positioned clip with mild-to-moderate MR (EROA – 21.5mm2 and regurgitant volume – 38mL) with the patient being completely asymptomatic.

Conclusion

Treatment of acute MR following AMI with MCI may be a safe and effective approach in critically ill patients. In our experience, it can lead to a rapid clinical recovery and resolution of cardiogenic shock.

P1262 If anything can go wrong, it will: management of a pericardial effusion in a young patient

Case Report

A 25 year-old male patient with an unremarkable past medical history presented to the Emergency Department due to a hemodynamically stable wide complex tachycardia at 260bpm with no response to adenosine, which was successfully treated with synchronized electrical cardioversion. Post cardioversion EKG revealed a pre excitation pattern and the transthoracic echocardiogram showed a large pericardial effusion with diastolic right atrial collapse. The patient was admitted in the Cardiology Department for emergent pericardiocentesis and further investigation. A total of 800 mL of bloody pericardial fluid was removed, compatible with an exudate, but fluid culture and cytology were inconclusive. Due to a rapid reaccumulation of pericardial fluid, the patient underwent a pericardial window, after which he developed an intractable pleuritic thoracalgia, refractory to the combination of ibuprofen, colchicine and oral steroid, despite the resolution of the pericardial effusion. He was also submitted to an electrophysiologic study with successful ablation of a right sided accessory pathway. Analysis of the pericardial fluid and biopsy were inconclusive once again, including a low level of adenosine deaminase and negative acid-fast bacilli test and nucleic acid amplification test for Mycobacterium tuberculosis. The patient was afebrile and denied any constitutional symptoms or relevant epidemiological context. The remainder etiological study was unremarkable, with the exception of fluctuating antibody titers for adenovirus, Borrelia burgdorferi and Mycoplasma pneumoniae, which were interpreted as a result of cross-reactivity. Nevertheless, a course of 21 days of doxycycline was tried without any significant improvement. Thoracic-abdominal-pelvic CT and PET scan were normal. Direct inoculation in guinea pig led to positive results for Mycobacterium tuberculosis and antituberculous therapy was started. Despite pathogen directed antibiotic treatment, there was no clinical improvement and the pericardial effusion gradually relapsed, evolving to cardiac tamponade requiring emergent drainage. Histologic examination of pericardial fragments finally revealed massive infiltration by an undifferentiated malignant tumor compatible with a malignant epithelioid hemangioendothelioma. Due to the patient’s poor performance status and rapidly deteriorating clinical course, it was decided not to start chemotherapy. The patient eventually died, 6 months after his admission to the ED and 2 weeks after the neoplasm’s diagnosis.

Conclusion

In regions with a high Tuberculosis incidence, there should be a high degree of suspicion for tuberculous pericarditis, especially in cases of recurrent pericardial effusion. Immunosuppressed individuals, such as oncologic patients, are at an increased risk for tuberculosis. The management of relapsing pericardial effusion remains a diagnostic challenge as described in this clinical case.

P697Regional analysis of 3D-derived speckle tracking for the assessment of myocardial deformation in breast cancer patients submitted to anthracycline chemotherapy

Introduction

Serial echocardiographic assessment of left ventricular ejection fraction (LVEF) and 2D left ventricular global longitudinal strain (GLS) is the gold standard in screening for cancer therapeutics-related cardiac dysfunction (CTRCD). Myocardial deformation assessed with 3D speckle tracking is not currently used in this setting, because of the lack of standardization and cut-off values, in spite of a potential for a greater reliability.

Methods

Prospective study of female breast cancer patients submitted to anthracycline chemotherapy with or without adjuvant immunotherapy and/or radiotherapy who underwent serial monitoring by 2D and 3D transthoracic echocardiography (ETT). Standard ETT measures and 3D-derived volumetric measures were assessed. Speckle tracking was used to estimate 2D-derived GLS – average and 18 segments – and 3D-derived GLS, global circumferential strain (GCS), global area strain (GAS) and global radial strain (GRS) – average and 17 segments. CTRCD was defined as an absolute decrease in 2D or 3D LVEF >10% to a value <54% or a relative decrease in 2D GLS >15%. Variables were compared using the t-student paired test and the Wilcoxon sign-rank test, when appropriate.

Results

106 patients (mean age 54.6±12.9 years, 33.0% immunotherapy, 16.5% radiotherapy, baseline LVEF 64.5% ± 8.5%, baseline 2D GLS −21.0±2.8) were included. During a mean follow-up of 16.5±9.6 months, an average of 3.9 echocardiographic examinations were performed per patient and 28 patients (26.4%) developed CTRCD. Overall, 3D regional longitudinal strain was determined in 88.9% of the segments analyzed, with lower success rates in the inferobasal (75.0%), the posterobasal (77.7%) and the laterobasal (82.4%) walls. When comparing variables before and during treatment, there was a significant difference in 2D-derived LVEF (64.5 vs. 57.6 p<0.001), 3D-derived LVEF (60.1 vs. 55.7 p 0.002), 2D-derived GLS (−20.6 vs. −18.2 p<0.001), 3D-derived GLS (−13.8 vs. −12.9 p 0.035), 3D-derived GRS (31.9 vs. 33.4 p 0.024), but not in GCS (−14.5 vs. −13.2 p 0.656) and GAS (−21.5 vs. −22.1 p 0.640). Figure 1 shows the segmental analysis of 2D and 3D strain parameters. In 2D GLS, 11 out of 18 segments showed decreased contractility during follow-up (mainly anterior septum and anterior, lateral and inferior walls). In 3D-derived strain parameters, only 3 out 17 for GLS, 2 out of 17 for GCS, 1 out 17 for GRS and none for GAS showed decreased contractility during follow-up.

Segmental analysis of 2D and 3D strain

Conclusion

In this population, there was worsening of 3D GLS and GRS, besides conventional values, such as LVEF and 2D GLS, during anthracycline-based cancer treatment. 3D-derived myocardial deformation parameters show promise in the setting of CTRCD, since 2D and 3D regional strain parameters might shed a light onto the mechanisms of CTRCD, such that subendocardial myocardial fibers seem to be more affected than medial and subepicardial fibers.

Tuberculous Skeletal Muscle Involvement in Acute Leukemia: Report on Two Cases

Bacterial infection of skeletal muscle (pyomyositis) is usually followed by abscess formation. The most commonly isolated pathogen is Staphylococcus aureus. Tuberculosis rarely affects patients with acute leukemia. The authors report on 2 patients, one with acute myelogenous leukemia and the other with acute lymphoblastic leukemia whose clinical course was complicated by tuberculous skeletal muscle abscesses. In both instances, musculoskeletal pain was accompanied by evidence of muscle abscesses by imaging studies of the painful areas. Therefore, in patients with acute leukemia and evidence of muscle abscesses with initial cultures negative for bacteria and fungi, one should include tuberculosis in the differential diagnosis.