Feasibility and long-term effectiveness of a non-apical Micra pacemaker implantation in a referral centre for lead extraction.

AIMS: To demonstrate the feasibility and long-term performances of a non-apical Micra pacemaker implantation. METHODS AND RESULTS: Fifty-two consecutive patients underwent Micra implantation, targeting a non-apical site of delivery when feasible. Each patient received a regular follow-up (mean 13 ± 9 months). The first 17 patients were also enrolled in the Micra transcatheter pacing system trial (Group 1); the remaining ones presented broader indications and included post-extraction subjects (Group 2). In 19 of 52 patients (Group 1: 6%, Group 2: 51%; P = 0.002) Micra was implanted because of high-risk characteristics that discouraged the implantation of a traditional pacemaker. In 31 of 52 patients (60%) Micra was implanted in a non-apical location, with a lower rate of single delivery compared with apical sites (48% vs. 81%, P = 0.035), but without any impact on electrical performance. Pacing threshold remained optimal in the majority of patients (94%), regardless of the site of implantation (apical vs. non-apical location: 0.50 vs. 0.52 V/0.24 ms; P = 0.856) and group membership, with only 6% of the subjects showing elevated values (mean 1.92 ± 0.92 V/0.24 ms) at the last follow-up. No device-related adverse events were registered. CONCLUSION: Micra pacemaker implant is a safe and effective procedure even in a real life cohort of high-risk patients. A non-apical site of implantation is feasible in the majority of patients allowing stable electrical performance at long-term follow-up.

Micra pacemaker implant after cardiac implantable electronic device extraction: feasibility and long-term outcomes.

AIMS: We aimed at investigating the feasibility and outcome of Micra implant in patients who have previously undergone transvenous lead extraction (TLE), in comparison to naïve patients implanted with the same device. METHODS AND RESULTS: Eighty-three patients (65 males, 78.31%; 77.27 ± 9.96 years) underwent Micra implant at our centre. The entire cohort was divided between 'post-extraction' (Group 1) and naïve patients (Group 2). In 23 of 83 patients (20 males, 86.96%; 73.83 ± 10.29 years), Micra was implanted after TLE. Indication to TLE was an infection in 15 patients (65.21%), leads malfunction in four (17.39%), superior vena cava syndrome in three (13.05%), and severe tricuspid regurgitation in one case (4.35%). The implant procedure was successful in all patients and no device-related events occurred at follow-up (median: 18 months; interquartile range: 1-24). No differences were observed between groups in fluoroscopy time (13.88 ± 10.98 min vs. 13.15 ± 6.64 min, P = 0.45), single device delivery (Group 1 vs. Group 2: 69.56% vs. 55%, P = 0.22), electrical performance at implant and at 12-month follow-up (Group 1 vs. Group 2: pacing threshold 0.48 ± 0.05 V/0.24 ms vs. 0.56 ± 0.25 V/0.24 ms, P = 0.70; impedance 640 ± 148.83 Ohm vs. 583.43 ± 99.7 Ohm, P = 0.27; and R wave amplitude 10.33 ± 2.88 mV vs. 12.62 ± 5.31 mV, P = 0.40). A non-apical site of implant was achievable in the majority of cases (72.3%) without differences among groups (78.26% vs. 70%; P = 0.42). CONCLUSION: Micra implant is an effective and safe procedure in patients still requiring a ventricular pacing after TLE, with similar electrical performance and outcome compared with naïve patients at long-term follow-up.

What Is New in Risk Assessment in Nuclear Cardiology?

Nuclear cardiology techniques allow in-depth evaluation of cardiac patients. A body of literature has established the use of nuclear cardiology. The results obtained with traditional cameras have been reinforced by those obtained with a series of innovations that have revolutionized the field of nuclear cardiology. This article highlights the role of nuclear cardiology in the risk assessment of patients with cardiac disease and sheds light on advancements of nuclear imaging techniques in the cardiovascular field. Patient risk stratification has a key role in modern precision medicine. Nuclear cardiac imaging techniques may quantitatively investigate major disease mechanisms of different cardiac pathologies.

Comparison between leadless and transvenous single-chamber pacemaker therapy in a referral centre for lead extraction.

PURPOSE: The aim of the study was to compare the long-term clinical and electrical performance of Micra leadless pacemaker with transvenous single-chamber pacemaker (TV-VVI PM) in a high-volume centre for transvenous lead extraction (TLE). METHODS: One-hundred patients (group 1) undergoing Micra implant were matched with 100 patients undergoing TV-VVI PM implant (group 2) by age, sex, left ventricular systolic ejection fraction and previous TLE. RESULTS: The implant procedure was successful in all patients. In group 1, the procedure duration was lower than in group 2 (43.86 ± 22.38 vs 58.38 ± 17.85 min, p < 0.001), while the fluoroscopy time was longer (12.25 ± 6.84 vs 5.32 ± 4.42 min, p < 0.001). There was no difference about the rate of septal implant at the right ventricle (76% vs 86%, p = 0.10). Patients were followed-up for a median of 12 months. No acute and chronic procedure-related complication was observed in group 1, while we reported acute complications in seven patients (7%, p = 0.02) and long-term complications in three patients (3%, p = 0.24), needing for a system revision in 6 cases (6%, p = 0.038), in group 2. One systemic infection occurred in TV-VVI PM group. Electrical measurements were stable during follow-up in both groups, with a longer estimated battery life in group 1 (mean delivered energy at threshold at discharge: 0.14 ± 0.21 vs 0.26 ± 0.22 µJ, p < 0.001). CONCLUSION: Micra pacemaker implant is a safe and effective procedure, with a lower rate of acute complications and system revisions compared with TV-VVI PM, even in a real-life setting including patients who underwent TLE.

Predictors of zero X ray procedures in supraventricular arrhythmias ablation.

To evaluate predictors of zero-X ray procedures for supraventricular arrhythmias (SVT) using minimally fluoroscopic approach (MFA). Patients referred for RF catheter ablation of SVT were admitted for a MFA with an electro-anatomical navigation system or a conventional fluoroscopic approach (ConvA). Exclusion criterion was the need to perform a transseptal puncture. 206 patients (98 men, age 53 ± 19 years) underwent an EP study, 93 (45%) with an MFA and 113 (55%) with a ConvA. Fifty-five had no inducible arrhythmias (EPS). Fifty-four had AV nodal reentrant tachycardia (AVNRT), 49 patients had typical atrial flutter (AFL), 37 had AV reciprocating tachycardia (AVRT/WPW), 11 had focal atrial tachycardia (AT), and underwent a RF ablation. X-ray was not used at all in 51/93 (58%) procedures (zero X ray). MFA was associated with a significant reduction in total fluoroscopy time (5.5 ± 10 vs 13 ± 18 min, P = 0.01) and operator radiation dose (0.8 ± 2.5 vs 3 ± 8.2 mSV, P < 0.05). The greatest absolute dose reduction was observed in AVNRT (0.1 ± 0.3 vs 5.1 ± 10 mSV, P = 0.01, 98% relative dose reduction) and in AFL (1.3 ± 3.6 vs 11 ± 16 mSV, P = 0.003, 88% relative dose reduction) groups. Both AVNRT or AFL resulted the only statistically significant predictors of zero x ray at multivariate analysis (OR 4.5, 95% CI 1.5-13 and OR 5, 95% CI 1.7-15, P < 0.001, respectively). Success and complication rate was comparable between groups (P = NS). Using MFA for SVT ablation, radiological exposure is significantly reduced. Type of arrhythmia is the strongest predictor of zero X ray procedure.

Utility of risk scores to predict adverse events in cardiac lead extraction.

INTRODUCTION: Increasing device implantations, patient comorbidities, and longer life expectancy contribute to an increased need for lead extraction. Even if transvenous lead extraction (TLE) is a highly successful procedure, some serious procedural complications are reported. In order to identify those patients who are at higher risk, risk stratification scores were proposed. Areas covered: The major obstacles to lead extractions are represented by the body's response to the foreign implanted material and by the following development of fibrotic reaction between the lead and the vascular system. Several clinical factors and device features are associated with major complications and worse outcomes. Although different multiparametric scores predicting the safety and the efficacy of TLE procedures were reported, none of these scores were prospective evaluated. Expert commentary: A correct risk stratification is needed in order to refer complex patients to centers with proven experience and avoid futile procedures. Furthermore, the identification of high-risk patients allows to perform the extraction procedure in the operating room instead of electrophysiology lab. Albeit some risk scores able to predict adverse event in cardiac lead extraction were described, there are still several limitations to their use and reproducibility.