Left ventricular assist device in the presence of subcutaneous implantable cardioverter defibrillator: Data from a multicenter experience.

BACKGROUND: Left ventricular assist devices (LVADs) are an increasingly used strategy for the management of patients with advanced heart failure (HF). Subcutaneous implantable cardioverter defibrillator (S-ICD) might be a viable alternative to conventional ICDs with a lower risk of short- and long-term of device-related complications and infections.The aim of this multicenter study was to evaluate the outcomes and management of S-ICD recipients who underwent LVAD implantation. METHODS: The study population included patients with a preexisting S-ICD who underwent LVAD implantation for advanced HF despite optimal medical therapy. RESULTS: The study population included 30 patients (25 male; median age 45 [38-52] years).The HeartMate III was the most common LVAD type. Median follow-up in the setting of concomitant use of S-ICDs and LVADs was 7 months (1-20).There were no reports of inability to interrogate S-ICD systems in this population. Electromagnetic interference (EMI) occurred in 21 (70%) patients. The primary sensing vector was the one most significantly involved in determining EMI. Twenty-seven patients (90%) remained eligible for S-ICD implantation with at least one optimal sensing vector. The remaining 3 patients (10%) were ineligible for S-ICD after attempts of reprogramming of sensing vectors. Six patients (20%) experienced inappropriate shocks (IS) due to EMI. Six patients (20%) experienced appropriate shocks. No S-ICD extraction because of need for antitachycardia pacing, ineffective therapy or infection was reported. CONCLUSIONS: Concomitant use of LVAD and S-ICD is feasible in most patients. However, the potential risk of EMI oversensing, IS and undersensing in the post-operative period following LVAD implantation should be considered. Careful screening for EMI should be performed in all sensing vectors after LVAD implantation.

Third-generation subcutaneous implantable cardioverter defibrillator and intermuscular two-incision implantation technique in patients with Arrhythmogenic cardiomyopathy: 3-year follow-up.

BACKGROUND: Long-term data on the potential advantages of combining the third-generation subcutaneous implantable cardioverter defibrillator (S-ICD) with modern software upgrade including the "SMART Pass", modern programming strategies and the intermuscular (IM) two-incision implantation technique in arrhythmogenic cardiomyopathy (ACM) with different phenotypic variants are lacking. In this study we evaluated the long-term outcome of patients with ACM who underwent third-generation S-ICD (Emblem, Boston Scientific) and IM two-incision technique. METHODS: The study population included 23 consecutive patients [70% male, median age 31 (24-46) years] diagnosed with ACM with different phenotypic variants who received third-generation S-ICD implantation with the IM two-incision technique. RESULTS: During a median follow-up of 45.5 months [16-65], 4 patients (17.4%) received a at least one inappropriate shock (IS), with median annual event rate of 4.5%. Extra-cardiac oversensing (myopotential) during effort represented the only cause of IS. No IS due to T-wave oversensing (TWOS) were recorded. Only one patient (4.3%) experienced device-related complication consisting of premature cell battery depletion requiring device replacement. No device explantation because of need for anti-tachycardia pacing or ineffective therapy occurred. There was no significant difference between patients who did and did not experienced IS with regard to baseline clinical, ECG and technical characteristics. Five patients (21.7%) received appropriate shocks on ventricular arrythmias. CONCLUSIONS: According to our findings, although the third-generation S-ICD implanted with the IM two-incision technique appears to be associated with a low risk of complications and IS due to cardiac oversensing, the risk of IS due to myopotential mainly during effort should be considered.

Outcomes of transvenous lead extraction in octogenarians using bidirectional rotational mechanical sheaths.

BACKGROUND: Outcomes of transvenous lead extraction (TLE) are well reported in the general population, However, data on safety, efficacy of TLE in octogenarians with a long lead dwell time, using powered extraction tools are limited. The aim of this multicenter study was to evaluate the safety, effectiveness of TLE in octogenarians using the bidirectional rotational mechanical sheaths and mid-term outcome after TLE. METHODS: The study population comprised 83 patients (78.3% male; mean age 85 ± 3 years; [range 80-94 years]) with 181 target leads. All the leads (mean implant duration 112 ± 77 months [range 12-377]) were extracted exclusively using the Evolution RL sheaths (Cook Medical, Bloomington, IN, USA). RESULTS: The main indication for TLE was infection in 84.3% of cases. Complete procedural success rate, clinical success rate, per lead were 93.9% and 98.3%, respectively. Failure of lead extraction was seen in 1.7% of leads. The additional use of a snare was required in 8.4% of patients. Major complications occurred in one patient (1.2%). Thirty-day mortality after TLE was 6%. During a mean time follow-up of 22 ± 21 months, 24 patients (29%) died. No procedure-related mortality occurred. Predictors of mortality included ischemic cardiomyopathy (HR 4.35; 95% CI 1.87-10.13; p = .001), left ventricularejection fraction ≤35% (HR 7.89; 95% CI 3.20-19.48; p < .001), and TLE for systemic infection (HR 4.24; 95% CI 1.69-10.66; p = .002). CONCLUSIONS: At experienced centers bidirectional rotational mechanical sheaths combined with different mechanical tools and femoral approach allowreasonable success and safety in octogenarian with long lead dwell time. Patient's age should not influence the decision to extract or not the leads, although the 30-day and mid-term mortality are significant, especially in the present of specific comorbidities.

Intermuscular two-incision technique for implantation of the subcutaneous implantable cardioverter defibrillator: a 3-year follow-up.

PURPOSE: The aim of the present study was to evaluate the outcome of patients underwent subcutaneous implantable cardioverter defibrillator (S-ICD) implantation with the intermuscular (IM) two-incision technique during 3-year follow-up. METHODS: the study population consisted of 105 consecutive patients (79 male; median 50 [13-77] years) underwent S-ICD implantation with the IM two-incision technique. The composite primary end point of the study consisted of device-related complications and inappropriate shocks (IAS). Secondary end points included the individual components of the primary end point, death from any cause, appropriate therapy, major adverse cardiac events, hospitalization for heart failure, and heart transplantation. RESULTS: According to the PRAETORIAN score, the risk of conversion failure was classified as low in 99 patients (94.3%), intermediate in 6 (5.7%).Ventricular fibrillation was successfully converted at ≤65 J in 97.4% of patients. During a median follow-up of 39 (16-53) months, 10 patients (9.5%) experienced device-related complications, and 9 (8.5%) patients reported IAS. Lead-associated complications were the most common (5 patients, 4.7%), including 2 cases of lead failure (1.9%). Pocket complications were reported in 2 patients (1.9%). Extra-cardiac oversensing (3.8%) represented the leading cause of IAS. No T-wave oversensing episodes were recorded. Twelve patients (11.4%) experienced appropriate shocks. Eight patients (7.6%) died during follow-up. IAS or device-related complications did not impact on mortality. CONCLUSIONS: The overall device-related complications and IAS rates over 3 years of follow-up were 9.5% and 8.5%, respectively. According to our findings, the IM two-incision technique allows for optimal positioning of the device achieving a low PRAETORIAN score with a high conversion rate. IM two-incision technique allows low incidence of pocket complications, shifting the type of complications towards lead-related complications, which represent the most common complications. The IM two-incision technique would not seem to impact the occurrence of IAS. Management of complications are safe without impact on the outcome.

Propofol dose and efficacy of defibrillation testing during implantation of subcutaneous implantable cardioverter-defibrillators: A retrospective, single center cohort study.

INTRODUCTION: Defibrillation testing (DFT) is recommended during subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation. Previous studies analyzing the potential interference of propofol with defibrillation threshold are inconsistent. The purpose of this study was to analyze whether propofol affects DFT post S-ICD placement. METHODS: All patients with S-ICD implantation between 01/2017 and 11/2020 at the University Heart Center Freiburg were retrospectively analyzed. Two groups were generated depending on the success of the first shock during DFT. Implantation characteristics and dose of anesthetics were analyzed. RESULTS: In 12 of the included 80 (15%) patients, first shock during DFT failed. The absolute dose of propofol was significantly higher in patients with first shock failure (median 653 mg [IQR 503-855]) compared to patients with first shock termination (376 mg [200-600]; p = 0.027). Doses of opioids and midazolam as well as type of anesthesia did not differ between the groups. A multivariable binary logistic regression analysis confirmed an independent association of first shock termination and propofol dose (per 100 mg: OR 0.73 (95% CI: 0.56-0.95); p = 0.021). CONCLUSION: There is an independent association of propofol dose and first shock failure in routine S-ICD defibrillation testing.

Outcomes of transvenous lead extraction of very old leads using bidirectional rotational mechanical sheaths: Results of a multicentre study.

INTRODUCTION: Lead dwell time >10 years is a recognized predictor for transvenous lead extraction (TLE) failure and complications. Data on the efficacy and safety of TLE using the bidirectional rotational mechanical sheaths in patients with very old leads are lacking. In this multicenter study, we reported the outcomes of transvenous rotational mechanical lead extraction in patients with leads implanted for ≥10 years. METHODS: A total of 441 leads (median: 159 months [135-197]; range: 120-487) in 189 consecutive patients were removed with the Evolution RL sheaths (Cook Medical, Bloomingtom, IN, USA) and mechanical ancillary tools supporting the procedures. RESULTS: The main indication for TLE was infection in 74% of cases. Complete procedural success rate, clinical success rate, per lead were 94.8% and 98.2%, respectively. Failure of lead extraction was seen in 1.8% of leads. The additional use of a snare via the femoral approach was required in 9% of patients. Lead dwell time was the only predictor of incomplete led removal (odds ratio: 1.009; 95% confidence interval [CI]: 1.003-1.014; p = .002). Four major complication (2%) were encountered. During a mean time follow-up of 31 ± 27 months, 21 patients (11%) died. No procedure-related mortality occurred. Predictors of mortality included severe left ventricular systolic dysfunction (hazard ratio [HR]: 8.06; 95% CI: 2.99-21.73; p = .001), TLE for infection (HR: 8.0; 95% CI: 1.04-62.5; p = .045), diabetes (HR: 3.7; 95% CI: 1.48-9.5; p = .005), and previous systemic infection (HR: 3.1; 95% CI: 1.17-8.24; p = .022). Incomplete lead removal or failure lead extraction did not impact on survival during follow-up. CONCLUSION: Our findings demonstrated that the use of bidirectional rotational TLE mechanical sheaths combined with different mechanical tools and femoral approach allows reasonable success and safety in patients with very old leads at experienced specialized centers.

Initial Clinical Experience With a Novel 8-Spline High-Resolution Mapping Catheter.

BACKGROUND: The Octaray (Biosense Webster) is a novel, multispline mapping catheter with 48 closely spaced microelectrodes enabling high-resolution electroanatomical mapping. OBJECTIVES: This study sought to report the initial clinical mapping experience with this novel catheter in a variety of cardiac arrhythmias and to compare the mapping performance with the 5-spline Pentaray. METHODS: Fifty consecutive procedures among 46 patients were retrospectively analyzed regarding safety, efficacy, and acute procedural success defined as termination or noninducibility of clinical tachycardia, conduction block across an ablation line, or pulmonary vein isolation. In addition, another 10 patients with sustained atrial tachycardia mapped with the 5-spline catheter (2-5-2 spacing) or the novel 8-spline catheter (2-2-2-2-2 spacing) were analyzed. RESULTS: Left atrial and ventricular mapping by either transseptal (n = 41) or retroaortic (n = 2) access was feasible without any complications related to the multispline design of the novel catheter. The acute procedural success rate was 94%. In sustained atrial tachycardia compared with the 5-spline catheter, the novel 8-spline catheter recorded more electrograms per map (3,628 ± 714 vs 11,350 ± 1,203; P < 0.001) in a shorter mapping time (13 ± 2 vs 9 ± 1 minutes; P = 0.08) resulting in a higher point density (18 ± 4 vs 59 ± 10 electrograms/cm2; P < 0.01) and point acquisition rate (308 ± 69 vs 1,332 ± 208 electrograms/min.; P < 0.01). CONCLUSIONS: In this initial experience, mapping with the novel catheter was safe and efficient with a high electroanatomical resolution. In sustained atrial tachycardia the novel 8-spline catheter demonstrated a marked increase in point density and mapping speed compared with those of the 5-spline catheter. These initial results should be validated in a larger multicenter cohort with longer follow-up.

Subcutaneous implantable cardioverter defibrillator after transvenous lead extraction: safety, efficacy and outcome.

BACKGROUND: Subcutaneous implantable cardioverter defibrillator (S-ICD) is a suitable alternative for transvenous ICD (TV-ICD) patients who have undergone transvenous lead extraction (TLE). Limited data are available on the outcome of S-ICD patients implanted after TLE. We assessed the safety, efficacy, and outcome of S-ICD implantation after TLE of TV-ICD. METHODS: The study population consisted of 36 consecutive patients with a median age of 52 (44-66) years who underwent S-ICD implantation after TLE of TV-ICD. RESULTS: Indications for TLE were infection (63.9%) and lead malfunction (36.1%). During a median follow-up of 31 months, 3 patients (8.3%) experienced appropriate therapy and 7 patients (19.4%) experienced complications including inappropriate therapy (n = 4; 11.1%), isolated pocket erosion (n = 2; 5.5%), and ineffective therapy (n = 1; 2.8%). No lead/hardware dysfunction was reported. Premature device explantation occurred in 4 patients (11%). Eight patients (22.2%) died during follow-up, six of them (75%) because of refractory heart failure (HF). There were no S-ICD-related deaths. Predictors of mortality included NYHA class ≥ 2 (HR 5.05; 95% CI 1.00-26.38; p = 0.04), hypertension (HR 22.72; 95% CI 1.05-26.31; p = 0.02), diabetes (HR 10.64; 95% CI 2.05-55.60; p = 0.001) and ischemic heart disease (HR 5.92; 95% CI 1.17-30.30; p = 0.01). CONCLUSION: Our study provides evidences on the use of S-ICD as an alternative after TV-ICD explantation for both infection and lead failure. Mortality of S-ICD patients who underwent TV-ICD explantation does not appear to be correlated with the presence of a prior infection, S-ICD therapy (appropriate or inappropriate), or S-ICD complications but rather to worsening of HF or other comorbidities.

The valuable interaction among cardiac surgeon and electrophysiologist for transvenous rotational mechanical lead extraction.

BACKGROUND: Recent studies have shown that Evolution RL bidirectional rotational mechanical sheath (Cook Medical, USA) is an effective and safe technique for transvenous lead extraction (TLE). We reported our experience with the bidirectional rotational mechanical tools using a multidisciplinary approach highlighting the value of a joint cardiac surgeon and electrophysiologist collaboration. METHODS: The study population comprised 84 patients (77% male; mean age 65 ± 18 years) undergoing TLE. After a multidisciplinary evaluation, a combined procedure was considered. RESULTS: The main indication for TLE was infection in 54 cases (64%). Overall, 152 leads were extracted with a mean implant duration of 94 ± 63 months (range 12-421). Complete procedural success rate, clinical success rate, and lead removal with clinical success rate were 91.6% (77/84), 97.6% (82/84), and 98.6% (150/152), respectively. Eighteen combined procedures were performed in 12 patients (14%), such as "hybrid approach" (n = 2) or TLE concomitant to: 1) transcatheter aspiration procedure for large vegetation (n = 8); 2) left ventricular assistance device implantation as bridge to cardiac transplantation (n = 1); 3) permanent pacing with epicardial leads (n = 6); 4) tricuspid valve replacement (n = 1). One major complication (1.2%) and 11 (13%) minor complications were encountered. No injury to the superior vena cava occurred and no procedure-related deaths were reported. During a mean time follow-up of 21 ± 18 months, 17 patients (20%) died. They were more often diabetics (p = .02), and they underwent TLE more often for infection (p = .004). CONCLUSIONS: Our results support the finding that excellent outcomes can be achieved in performing TLE of chronically implanted leads by using the Evolution RL bidirectional rotational mechanical sheath and a multidisciplinary team approach involving both electrophysiologist and cardiac surgeon as first line operators.

Electrocardiographic Predictors of Primary Ventricular Fibrillation and 30-Day Mortality in Patients Presenting with ST-Segment Elevation Myocardial Infarction.

Primary ventricular fibrillation (PVF) may occur in the early phase of ST-elevation myocardial infarction (STEMI) prior to primary percutaneous coronary intervention (PCI). Multiple electrocardiographic STEMI patterns are associated with PVF and short-term mortality including the tombstone, Lambda, and triangular QRS-ST-T waveform (TW). We aimed to compare the predictive value of different electrocardiographic STEMI patterns for PVF and 30-day mortality. We included a consecutive cohort of 407 STEMI patients (75% males, median age 66 years) presenting within 12 h of symptoms onset. At first medical contact, 14 (3%) showed the TW or Lambda ECG patterns, which were combined in a single group (TW-Lambda pattern) characterized by giant R-wave and downsloping ST-segment. PVF prior to primary PCI occurred in 39 (10%) patients, significantly more often in patients with the TW-Lambda pattern than those without (50% vs. 8%, p < 0.001). For the multivariable analysis, Killip class ≥3 (OR 6.19, 95% CI 2.37-16.1, p < 0.001) and TW-Lambda pattern (OR 9.64, 95% CI 2.99-31.0, p < 0.001) remained as independent predictors of PVF. Thirty-day mortality was also higher in patients with the TW-Lambda pattern than in those without (43% vs. 6%, p < 0.001). However, only LVEF (OR 0.86, 95% CI 0.82-0.90, p < 0.001) and PVF (OR 4.61, 95% CI 1.49-14.3, p = 0.042) remained independent predictors of mortality. A mediation analysis showed that the effect of TW-Lambda pattern on mortality was mediated mainly via the reduced LVEF. In conclusion, among patients presenting with STEMI, the electrocardiographic TW-Lambda pattern was associated with both PVF before PCI and 30-day mortality. Therefore, this ECG pattern may be useful for early risk stratification of STEMI.

Significance of post-pacing intervals shorter than tachycardia cycle length for successful catheter ablation of atypical flutter.

AIMS: During entrainment mapping of macro-reentrant tachycardias, the time difference (dPPI) between post-pacing interval (PPI) and tachycardia cycle length (TCL) is thought to be a function of the distance of the pacing site to the re-entry circuit and dPPI < 30 ms is considered within the re-entry circuit. This study assessed the importance of PPI < TCL as a successful target for atypical flutter ablation. METHODS AND RESULTS: A total of 177 ablation procedures were investigated. Surface electrocardiograms (ECGs) were evaluated and combined activation and entrainment mapping were performed to choose ablation sites. Each entrainment sequence immediately preceding static radiofrequency delivery at the same site was analysed. A total of 545 entrainment sequences were analysed. dPPI < 0 ms was observed in 45.3% (247/545) sequences. Ablation resulted in tachycardia termination more often at sites with dPPI < 0 (27.8% vs. 14.5%, P < 0.001) and with a progressively increasingly inverse correlation between dPPI duration and ablation success [odds ratio (OR): 0.974; 95% confidence interval (CI) 0.960-0.988; P < 0.001]. Tachycardia termination or cycle length prolongation also occurred more often at sites with dPPI < 0 (50.6% vs. 33.2%, P < 0.001) and with a similar inverse correlation with dPPI duration (OR: 0.972; 95% CI 0.960-0.984; P < 0.001). Twelve-lead synchronous isoelectric intervals were observed in 64.4% (163/253) flutter ECGs and were associated with a dPPI < 0 (75.3% vs. 55.8%, P < 0.001). CONCLUSION: When combined with activation mapping, a negative dPPI is a more effective parameter for identifying a target for successful ablation compared to a dPPI = 0-30 ms. Its occurrence is associated with a critical small narrow slow-conducting isthmus at the target site.

Electrophysiological and Anatomical Correlates of Sites With Postpacing Intervals Shorter Than Tachycardia Cycle Length in Atypical Atrial Flutter.

Background Although entrainment mapping is an established approach to atypical atrial flutter ablation, postpacing intervals shorter than tachycardia cycle length (difference between postpacing interval and tachycardia cycle length [dPPI] <0 ms) remain of unknown significance. We sought to compare anatomic and electrophysiological properties of sites with dPPI <0, dPPI=0-30, and dPPI >30 ms. Methods We studied 24 noncavotricuspid isthmus-dependent macroreentrant atypical atrial flutter in 19 consecutive patients. Ultra high-density electroanatomic activation maps were acquired with a 64-electrode basket catheter. Entrainment mapping was performed at multiple candidate sites. Ablation was performed at the narrowest accessible slow-conducting critical isthmuses. Results Of 102 entrainment mapping sites, dPPI <30 was observed at 72 sites on complete maps of 24 atypical atrial flutter. Compared with dPPI=0-30 sites (N=45), dPPI<0 sites (N=27) were more commonly located within isthmuses <15 mm wide (67% versus 6.7%, P<0.00001; odds ratio, 28.0; 95% CI, 6.8-115.7), more frequently located within 5 mm of the leading wavefront (93% versus 64%, P=0.008), exhibited slower local conduction velocity (0.49±0.43 versus 0.93±0.57 m/s, P=0.0005), lower voltages (0.48±0.79 versus 0.92±0.97 mV, P=0.04), and more frequently fractionated electrograms (67% versus 24%, P=0.0004). High rates of arrhythmia termination or cycle length increase >15 ms by ablation were observed in both dPPI groups (94% versus 86%, P=0.53). Compared with all dPPI <30, dPPI >30 sites (N=30) were less commonly observed within isthmuses (3.3%, P<0.001) or within 5 mm of the leading wavefront (30%, P<0.0001); conduction velocity (1.0±0.7 m/s, P=0.002) and voltage (1.1±1.4 mV, P=0.049) were higher compared with dPPI<0 but similar to dPPI=0-30 sites. Conclusions In atypical atrial flutter, sites with dPPI <0 are markers of limited width critical isthmuses with slower conduction velocity, whereas sites with dPPI=0-30 ms are often not in close proximity to the reentry circuit. Virtual electrode simultaneous down and upstream (antidromic) capture of a confined isthmus of slow conduction can explain a dPPI <0. Identifying these sites may improve selective and efficient ablation strategies compared with the standard 30-ms threshold.