BACKGROUND: The clinical utilization of leadless pacemakers (LPs) as an alternative to traditional transvenous pacemakers is likely to increase with the advent of dual-chamber LP systems. Since device retrieval to allow LP upgrade or replacement will become an important capability, the first such dual-chamber, helix-fixation LP system (Aveir DR; Abbott, Abbott Park, IL) was specifically designed to allow catheter-based retrieval. In this study, the preclinical performance and safety of retrieving chronically implanted dual-chamber LPs was evaluated. METHODS: Atrial and ventricular LPs were implanted in the right atrial appendage and right ventricular apex of 9 healthy ovine subjects. After ≈2 years, the LPs were retrieved using a dedicated transvenous retrieval catheter (Aveir Retrieval Catheter; Abbott) by snaring, docking, and unscrewing from the myocardium. Comprehensive necropsy/histopathology studies were conducted to evaluate device- and procedure-related outcomes. RESULTS: At a median of 1.9 years postimplant (range, 1.8-2.6), all 18 of 18 (100%) LPs were retrieved from 9 ovine subjects without complications. The median retrieval procedure duration for both LPs, from first-catheter-in to last-catheter-out, was 13.3 minutes (range, 2.5-36.4). Postretrieval, all right atrial, and right ventricular implant sites demonstrated minimal tissue disruption, with intact fibrous tissue limited to the distal device body. No significant device-related trauma, perforation, pericardial effusion, right heart or tricuspid valve injury, or chronic pulmonary thromboembolism were observed at necropsy. CONCLUSIONS: This preclinical study demonstrated the safe and effective retrieval of chronically implanted, helix-fixation, dual-chamber LP systems, paving the way for clinical studies of LP retrieval.
- MeSH
- design vybavení MeSH
- fibrilace síní * MeSH
- kardiostimulátor * MeSH
- lidé MeSH
- lipopolysacharidy MeSH
- ovce domácí MeSH
- ovce MeSH
- srdeční komory MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: During electrophysiological mapping of tachycardias, putative target sites are often only truly confirmed to be vital after observing the effect of ablation. This lack of mapping specificity potentiates inadvertent ablation of innocent cardiac tissue not relevant to the arrhythmia. But if myocardial excitability could be transiently suppressed at critical regions, their suitability as targets could be conclusively determined before delivering tissue-destructive ablation lesions. We studied whether reversible pulsed electric fields (PFREV) could transiently suppress electrical conduction, thereby providing a means to dissect tachycardia circuits in vivo. METHODS: PFREV energy was delivered from a 9-mm lattice-tip catheter to the atria of 12 swine and 9 patients, followed by serial electrogram assessments. The effects on electrical conduction were explored in 5 additional animals by applying PFREV to the atrioventricular node: 17 low-dose (PFREV-LOW) and 10 high-dose (PFREV-HIGH) applications. Finally, in 3 patients manifesting spontaneous tachycardias, PFREV was applied at putative critical sites. RESULTS: In animals, the immediate post-PFREV electrogram amplitudes diminished by 74%, followed by 78% recovery by 5 minutes. Similarly, in patients, a 69.9% amplitude reduction was followed by 84% recovery by 3 minutes. Histology revealed only minimal to no focal, superficial fibrosis. PFREV-LOW at the atrioventricular node resulted in transient PR prolongation and transient AV block in 59% and 6%, while PFREV-HIGH caused transient PR prolongation and transient AV block in 30% and 50%, respectively. The 3 tachycardia patients had atypical atrial flutters (n=2) and atrioventricular nodal reentrant tachycardia. PFREV at putative critical sites reproducibly terminated the tachycardias; ablation rendered the tachycardias noninducible and without recurrence during 1-year follow-up. CONCLUSIONS: Reversible electroporation pulses can be applied to myocardial tissue to transiently block electrical conduction. This technique of pulsed field mapping may represent a novel electrophysiological tool to help identify the critical isthmus of tachycardia circuits.
- MeSH
- atrioventrikulární blokáda * MeSH
- atrioventrikulární nodální reentry tachykardie * MeSH
- elektrofyziologické techniky kardiologické MeSH
- elektrokardiografie MeSH
- katetrizační ablace * škodlivé účinky metody MeSH
- lidé MeSH
- nodus atrioventricularis MeSH
- prasata MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: The inspIRE study (Study for Treatment of Paroxysmal Atrial Fibrillation [PAF] by Pulsed Field Ablation [PFA] System With Irreversible Electroporation [IRE]) evaluated safety and effectiveness of a fully integrated biphasic pulsed field ablation (PFA) system with a variable-loop circular catheter for the treatment of drug-refractory paroxysmal atrial fibrillation. METHODS: Subjects underwent pulmonary vein (PV) isolation with the PFA system, using at least 12 applications per vein; adenosine/isoproterenol was administered to confirm entrance block. Wave I assessed initial safety, including for esophageal lesions, silent cerebral lesions, and PV stenosis. Wave II (pivotal phase) tested (1) primary safety, incidence of early-onset primary adverse events, and (2) primary effectiveness, confirmed PV isolation with freedom from documented atrial arrhythmia at 12 months. The study design specified an interim analysis to determine early success once 30 subjects reached the 12-month follow-up and all subjects reached 3-month follow-up. RESULTS: Across 13 centers in Europe/Canada, 226 subjects were enrolled, met criteria for safety and effectiveness evaluations, and received PFA (Wave I, 40; Wave II, 186). Wave I demonstrated no esophageal thermal lesions or PV stenosis. Among 39 subjects with cerebral magnetic resonance imaging, silent cerebral lesions were detected in 4 of the first 6 subjects, after which workflow enhancements, including a 10-second pause between PFA applications, were implemented; subsequently, only 4 of 33 subjects had silent cerebral lesions. In the Wave II phase, no primary adverse events were reported. Upon declaring early success, 83 subjects reached 12-month follow-up. With 100% entrance block, PV isolation without acute reconnection was achieved in 97.1% of targeted veins. For Wave II, the primary effectiveness end point per Kaplan-Meier at the time of interim analysis was 70.9%; 12-month freedom from symptomatic atrial fibrillation/atrial flutter/atrial tachycardia recurrence and repeat ablation was 78.9% and 92.3%, respectively. Total procedure and transpired PFA times were 70.1±27.7 and 26.7±14.0 minutes, respectively. CONCLUSIONS: The inspIRE trial confirmed the safety and effectiveness of the novel mapping-integrated PFA system. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; unique identifier: NCT04524364.
- MeSH
- fibrilace síní * diagnóza chirurgie etiologie MeSH
- katetrizační ablace * škodlivé účinky metody MeSH
- katétry MeSH
- lidé MeSH
- recidiva MeSH
- stenóza plicní žíly * etiologie MeSH
- stenóza etiologie chirurgie MeSH
- venae pulmonales * chirurgie MeSH
- výsledek terapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- Geografické názvy
- Evropa MeSH
BACKGROUND: Leadless pacemakers (LPs) can mitigate conventional pacemaker complications related to the transvenous leads and subcutaneous pocket surrounding the pulse generator. Although single-chamber leadless pacing has been established, multichamber pacing requires wireless bidirectional communication across multiple LPs to maintain synchrony. This preclinical study demonstrates the chronic performance of implant-to-implant (i2i) communication that achieves synchronous, dual-chamber pacing with 2 LPs. METHODS: The i2i communication modality employs subthreshold electrical signals conducted between implanted LPs through the blood and myocardial tissue on a beat-by-beat basis. Right atrial and right ventricular LPs were implanted in 9 ovine subjects. The i2i transmission performance was evaluated 13 weeks after implant. RESULTS: Right atrial and right ventricular LPs were implanted successfully and without complication in 9 ovine subjects. A total of 8715±457 right atrial-to-right ventricular and right ventricular-to-right atrial transmissions were sent per hour, with a success rate of 99.2±0.9%. Of periods with i2i communication failure when DDD pacing was not possible, 97.3±1.8% were resolved within 6 s. CONCLUSIONS: For the first time, synchronized, dual-chamber pacing has been demonstrated in a chronic preclinical feasibility study by 2 leadless pacemakers using beat-to-beat, wireless communication, achieving a success rate of 99.2%.
BACKGROUND: Maximal left ventricular wall thickness (MLVWT) is a risk factor for sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). In adults, the severity of left ventricular hypertrophy has a nonlinear relationship with SCD, but it is not known whether the same complex relationship is seen in childhood. The aim of this study was to describe the relationship between left ventricular hypertrophy and SCD risk in a large international pediatric HCM cohort. METHODS: The study cohort comprised 1075 children (mean age, 10.2 years [±4.4]) diagnosed with HCM (1-16 years) from the International Paediatric Hypertrophic Cardiomyopathy Consortium. Anonymized, noninvasive clinical data were collected from baseline evaluation and follow-up, and 5-year estimated SCD risk was calculated (HCM Risk-Kids). RESULTS: MLVWT Z score was <10 in 598 (58.1%), ≥10 to <20 in 334 (31.1%), and ≥20 in 143 (13.3%). Higher MLVWT Z scores were associated with heart failure symptoms, unexplained syncope, left ventricular outflow tract obstruction, left atrial dilatation, and nonsustained ventricular tachycardia. One hundred twenty-two patients (71.3%) with MLVWT Z score ≥20 had coexisting risk factors for SCD. Over a median follow-up of 4.9 years (interquartile range, 2.3-9.3), 115 (10.7%) had an SCD event. Freedom from SCD event at 5 years for those with MLVWT Z scores <10, ≥10 to <20, and ≥20 was 95.6%, 87.4%, and 86.0, respectively. The estimated SCD risk at 5 years had a nonlinear, inverted U-shaped relationship with MLVWT Z score, peaking at Z score +23. The presence of coexisting risk factors had a summative effect on risk. CONCLUSIONS: In children with HCM, an inverted U-shaped relationship exists between left ventricular hypertrophy and estimated SCD risk. The presence of additional risk factors has a summative effect on risk. While MLVWT is important for risk stratification, it should not be used either as a binary variable or in isolation to guide implantable cardioverter defibrillator implantation decisions in children with HCM.
- MeSH
- defibrilátory implantabilní * škodlivé účinky MeSH
- dítě MeSH
- dospělí MeSH
- hodnocení rizik MeSH
- hypertrofická kardiomyopatie * komplikace diagnostické zobrazování MeSH
- hypertrofie levé komory srdeční komplikace diagnostické zobrazování MeSH
- lidé MeSH
- náhlá srdeční smrt epidemiologie etiologie MeSH
- retrospektivní studie MeSH
- rizikové faktory MeSH
- srdeční komory diagnostické zobrazování MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
[Figure: see text].
- MeSH
- časové faktory MeSH
- chirurgie s pomocí počítače metody MeSH
- design vybavení MeSH
- dospělí MeSH
- fibrilace síní patofyziologie chirurgie MeSH
- fluoroskopie metody MeSH
- katetrizační ablace přístrojové vybavení MeSH
- lidé středního věku MeSH
- lidé MeSH
- následné studie MeSH
- převodní systém srdeční patofyziologie MeSH
- prospektivní studie MeSH
- recidiva MeSH
- senioři MeSH
- srdeční katétry * MeSH
- venae pulmonales chirurgie MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
[Figure: see text].
- MeSH
- akční potenciály MeSH
- časové faktory MeSH
- délka operace MeSH
- design vybavení MeSH
- doba přežití bez progrese choroby MeSH
- endoskopie škodlivé účinky přístrojové vybavení MeSH
- endoskopy * MeSH
- fibrilace síní diagnóza patofyziologie chirurgie MeSH
- katetrizační ablace škodlivé účinky přístrojové vybavení MeSH
- lidé středního věku MeSH
- lidé MeSH
- prospektivní studie MeSH
- recidiva MeSH
- senioři MeSH
- srdeční frekvence MeSH
- studie případů a kontrol MeSH
- venae pulmonales patofyziologie chirurgie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
BACKGROUND: Morbidity and mortality outcomes for patients admitted for acute decompensated heart failure are poor and have not significantly changed in decades. Current therapies are focused on symptom relief by addressing signs and symptoms of congestion. The objective of this study was to test a novel neuromodulation therapy of stimulation of epicardial cardiac nerves passing along the posterior surface of the right pulmonary artery. METHODS: Fifteen subjects admitted for defibrillator implantation and ejection fraction ≤35% on standard heart failure medications were enrolled. Through femoral arterial access, high fidelity pressure catheters were placed in the left ventricle and aortic root. After electro anatomic rendering of the pulmonary artery and branches, either a circular or basket electrophysiology catheter was placed in the right pulmonary artery to allow electrical intravascular stimulation at 20 Hz, 4 ms pulse width, and ≤20 mA. Changes in maximum positive dP/dt (dP/dtMax) indicated changes in ventricular contractility. RESULTS: Of 15 enrolled subjects, 5 were not studied due to equipment failure or abnormal pulmonary arterial anatomy. In the remaining subjects, dP/dtMax increased significantly by 22.6%. There was also a significant increase in maximum negative dP/dt (dP/dtMin), mean arterial pressure, systolic pressure, diastolic pressure, and left ventricular systolic pressure. There was no significant change in heart rate or left ventricular diastolic pressure. CONCLUSIONS: In this first-in-human study, we demonstrated that in humans with stable heart failure, left ventricular contractility could be accentuated without an increase in heart rate or left ventricular filling pressures. This benign increase in contractility may benefit patients admitted for acute decompensated heart failure.
- MeSH
- autonomní nervový systém patofyziologie MeSH
- časové faktory MeSH
- funkce levé komory srdeční * MeSH
- kardiostimulace umělá škodlivé účinky metody MeSH
- kontrakce myokardu * MeSH
- lidé středního věku MeSH
- lidé MeSH
- obnova funkce MeSH
- ověření koncepční studie MeSH
- senioři MeSH
- srdce inervace MeSH
- srdeční selhání diagnóza patofyziologie terapie MeSH
- výsledek terapie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: The tissue selectivity of pulsed field ablation (PFA) provides safety advantages over radiofrequency ablation in treating atrial fibrillation. One-shot PFA catheters have been shown capable of performing pulmonary vein isolation, but not flexible lesion sets such as linear lesions. A novel lattice-tip ablation catheter with a compressible 9-mm nitinol tip is able to deliver either focal radiofrequency ablation or PFA lesions, each in 2 to 5 s. METHODS: In a 3-center, single-arm, first-in-human trial, the 7.5F lattice catheter was used with a custom mapping system to treat paroxysmal or persistent atrial fibrillation. Toggling between energy sources, point-by-point pulmonary vein encirclement was performed using biphasic PFA posteriorly and either temperature-controlled irrigated radiofrequency ablation or PFA anteriorly (RF/PF or PF/PF, respectively). Linear lesions were created using either PFA or radiofrequency ablation. RESULTS: The 76-patient cohort included 55 paroxysmal and 21 persistent atrial fibrillation patients undergoing either RF/PF (40 patients) or PF/PF (36 patients) ablation. The pulmonary vein isolation therapy duration time (transpiring from first to last lesion) was 22.6±8.3 min/patient, with a mean of 50.1 RF/PF lesions/patient. Linear lesions included 14 mitral (4 RF/2 RF+PF/8 PF), 34 left atrium roof (12 RF/22 PF), and 44 cavotricuspid isthmus (36 RF/8 PF) lines, with therapy duration times of 5.1±3.5, 1.8±2.3, and 2.4±2.1 min/patient, respectively. All lesion sets were acutely successful, using 4.7±3.5 minutes of fluoroscopy. There were no device-related complications, including no strokes. Postprocedure esophagogastroduodenoscopy revealed minor mucosal thermal injury in 2 of 36 RF/PF and 0 of 24 PF/PF patients. Postprocedure brain magnetic resonance imaging revealed diffusion-weighted imaging+/fluid-attenuated inversion recovery- and diffusion-weighted imaging+/fluid-attenuated inversion recovery+ asymptomatic lesions in 5 and 3 of 51 patients, respectively. CONCLUSIONS: A novel lattice-tip catheter could safely and rapidly ablate atrial fibrillation using either a combined RF/PF approach (capitalizing on the safety of PFA and the years of experience with radiofrequency energy) or an entirely PF approach. Registration: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT04141007 and NCT04194307.
- MeSH
- akční potenciály MeSH
- časové faktory MeSH
- design vybavení MeSH
- elektrofyziologické techniky kardiologické MeSH
- fibrilace síní diagnóza patofyziologie chirurgie MeSH
- katetrizační ablace škodlivé účinky přístrojové vybavení MeSH
- léčebná irigace škodlivé účinky přístrojové vybavení MeSH
- lidé středního věku MeSH
- lidé MeSH
- prospektivní studie MeSH
- senioři MeSH
- srdeční frekvence MeSH
- srdeční katetrizace škodlivé účinky přístrojové vybavení MeSH
- srdeční katétry * MeSH
- venae pulmonales patofyziologie chirurgie MeSH
- výsledek terapie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
- klinické zkoušky MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Litva MeSH
BACKGROUND: A novel ablation and mapping system can toggle between delivering biphasic pulsed field (PF) and radiofrequency energy from a 9-mm lattice-tip catheter. We assessed the preclinical feasibility and safety of (1) focal PF-based thoracic vein isolation and linear ablation, (2) combined PF and radiofrequency focal ablation, and (3) PF delivered directly atop the esophagus. METHODS: Two cohorts of 6 swine were treated with pulsed fields at low dose (PFLD) and high dose (PFHD) and followed for 4 and 2 weeks, respectively, to isolate 25 thoracic veins and create 5 right atrial (PFLD), 6 mitral (PFHD), and 6 roof lines (radiofrequency+PFHD). Baseline and follow-up voltage mapping, venous potentials, ostial diameters, and phrenic nerve viability were assessed. PFHD and radiofrequency lesions were delivered in 4 and 1 swine from the inferior vena cava onto a forcefully deviated esophagus. All tissues were submitted for histopathology. RESULTS: Hundred percent of thoracic veins (25 of 25) were successfully isolated with 12.4±3.6 applications/vein with mean PF times of <90 seconds/vein. Durable isolation improved from 61.5% PFLD to 100% with PFHD (P=0.04), and all linear lesions were successfully completed without incurring venous stenoses or phrenic injury. PFHD sections had higher transmurality rates than PFLD (98.3% versus 88.1%; P=0.03) despite greater mean thickness (2.5 versus 1.3 mm; P<0.001). PF lesions demonstrated homogenous fibrosis without epicardial fat, nerve, or vessel involvement. In comparison, radiofrequency+PFHD sections revealed similar transmurality but expectedly more necrosis, inflammation, and epicardial fat, nerve, and vessel involvement. Significant ablation-related esophageal necrosis, inflammation, and fibrosis were seen in all radiofrequency sections, as compared with no PF sections. CONCLUSIONS: The lattice-tip catheter can deliver focal PF to durably isolate veins and create linear lesions with excellent transmurality and without complications. The PF lesions did not damage the phrenic nerve, vessels, and the esophagus.
- MeSH
- akční potenciály MeSH
- elektrofyziologické techniky kardiologické MeSH
- katetrizační ablace škodlivé účinky přístrojové vybavení metody MeSH
- léčebná irigace * škodlivé účinky přístrojové vybavení MeSH
- modely u zvířat MeSH
- pooperační komplikace patologie patofyziologie MeSH
- srdeční frekvence MeSH
- srdeční katétry MeSH
- srdeční síně patologie patofyziologie chirurgie MeSH
- studie proveditelnosti MeSH
- Sus scrofa MeSH
- venae pulmonales patologie patofyziologie chirurgie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
