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JACC. Clinical Electrophysiology Apr 2023QDOT MICRO (QDM) is a novel contact force-sensing catheter optimized for temperature-controlled radiofrequency (RF) ablation. The very high-power short-duration (vHPSD)...
BACKGROUND
QDOT MICRO (QDM) is a novel contact force-sensing catheter optimized for temperature-controlled radiofrequency (RF) ablation. The very high-power short-duration (vHPSD) algorithm modulates power, maintaining target temperature during 90 W ablations for ≤4 seconds.
OBJECTIVES
This study aims to evaluate safety and 12-month effectiveness of the QDM catheter in paroxysmal atrial fibrillation (AF) ablation using the vHPSD mode combined with conventional-power temperature-controlled (CPTC) mode.
METHODS
In this prospective, multicenter, nonrandomized study, patients with drug-refractory, symptomatic paroxysmal AF underwent pulmonary vein (PV) isolation with QDM catheter with vHPSD as primary ablation mode, with optional use of the CPTC mode (25 to 50 W) for PV touch-up or non-PV ablation. The primary safety endpoint was incidence of primary adverse events within ≤7 days of ablation. The primary effectiveness endpoint was freedom from documented atrial tachyarrhythmia recurrence and acute procedural, repeat ablation, and antiarrhythmic drug failure.
RESULTS
Of 191 enrolled participants, 166 had the catheter inserted, received RF ablation, and met eligibility criteria. Median procedural, RF application for ablating PVs, and fluoroscopy times were 132.0, 8.0, and 9.1 minutes, respectively. The primary adverse event rate was 3.6%. Imaging conducted in a subset of participants (n = 40) at 3 months did not show moderate or severe PV stenosis. The Kaplan-Meier estimated 12-month rate for primary effectiveness success was 76.7%; freedom from atrial tachyarrhythmia recurrence was 82.1%; clinical success (freedom from symptomatic recurrence) was 86.0%; and freedom from repeat ablation was 92.1%.
CONCLUSIONS
Temperature-controlled paroxysmal AF ablation with the novel QDM catheter in vHPSD mode (90 W, ≤4 seconds), alone or with CPTC mode (25 to 50 W), is highly efficient and effective without compromising safety. (Evaluation of QDOT MICRO Catheter for Pulmonary Vein Isolation in Subjects With Paroxysmal Atrial Fibrillation [Q-FFICIENCY]; NCT03775512).
Topics: Humans; Atrial Fibrillation; Temperature; Prospective Studies; Treatment Outcome; Catheter Ablation; Radiofrequency Ablation
PubMed: 36752484
DOI: 10.1016/j.jacep.2022.10.019 -
Journal of Arrhythmia Jun 2021Coronary injury presenting as ST segment elevation (STE) during ablation procedures for different arrhythmias is a rare and most feared complication. There have been... (Review)
Review
Coronary injury presenting as ST segment elevation (STE) during ablation procedures for different arrhythmias is a rare and most feared complication. There have been multiple reports on STE during various ablation procedures in the recent past. Herein, we review various mechanisms, presentations, and management of STE observed during various ablations, including atrial fibrillation ablation cavotricuspid isthmus and ablation, supraventricular tachycardia ablations, coronary sinus ablation, and ventricular arrhythmia ablations.
PubMed: 34141005
DOI: 10.1002/joa3.12526 -
Arrhythmia & Electrophysiology Review Aug 2018Techniques to ablate persistent atrial fibrillation (AF) continue to evolve. Recent technological and strategic innovations have included a focus on mapping and ablating... (Review)
Review
Techniques to ablate persistent atrial fibrillation (AF) continue to evolve. Recent technological and strategic innovations have included a focus on mapping and ablating AF sources. These attempts have not yet yielded a consistent improvement in clinical outcomes following AF ablation. Advancements in these techniques in the next few years, however, may enhance our ability to map and ablate AF as well as further our understanding of the mechanisms behind AF initiation, perpetuation, and recurrence.
PubMed: 30416729
DOI: 10.15420/aer:2018:25:2 -
International Journal of Hyperthermia :... Oct 2019A growing body of evidence is being published regarding the safety and efficacy of minimally invasive image-guided ablation techniques. While clinical applications of... (Review)
Review
A growing body of evidence is being published regarding the safety and efficacy of minimally invasive image-guided ablation techniques. While clinical applications of these techniques are increasing, international societies have started to publish treatment guidelines and to make efforts to standardize both terminology and reporting criteria for image-guided thyroid ablations. Laser ablation and radiofrequency ablation (RFA) are among the most common ablation techniques either for benign and malignant thyroid nodules. Unlike laser ablation and RFA in the treatment of benign thyroid nodules, where safety and efficacy have been widely demonstrated, evidence regarding local tumor control of thyroid malignancies is still limited. However, preliminary results are encouraging and image-guided thermal ablation techniques can be considered a valid alternative to surgery for the treatment of benign thyroid nodules and recurrent thyroid cancers. This review evaluates the basic concept of RFA and laser ablations, their techniques, clinical outcomes, and complications based on the suggestions of several society guidelines. Multidisciplinary collaboration remains critical to identify patients which may benefit from minimally invasive image-guided thermal ablations, especially if surgery or radioiodine therapy are not feasible options.
Topics: Catheter Ablation; Humans; Laser Therapy; Thyroid Neoplasms; Treatment Outcome
PubMed: 31537159
DOI: 10.1080/02656736.2019.1622795 -
Circulation Journal : Official Journal... 2012The aortic root is at the center of the heart. Each of the aortic sinuses of Valsalva, positioned at the base of the aortic root, is in contact with the atrial... (Review)
Review
The aortic root is at the center of the heart. Each of the aortic sinuses of Valsalva, positioned at the base of the aortic root, is in contact with the atrial myocardium and/or ventricular myocardium at their bases, which enables mapping and ablating of some ventricular arrhythmias with an outflow tract origin and supraventricular tachycardias (ie, atrial tachycardia, accessory pathways) from the aortic sinuses of Valsalva. These arrhythmias have characteristic electrocardiographic findings associated with their origins, and almost all are difficult to ablate from an atrial or ventricular endocardial site. Site-specific and potential complications, such as a coronary artery occlusion or atrioventricular block, can occur with catheter ablation at the aortic sinuses of Valsalva. Therefore, accurate diagnosis and proper ablation at the aortic sinuses of Valsalva are required for a cure. This review describes the anatomic features of the aortic sinuses of Valsalva and focuses on the diagnosis and radiofrequency catheter ablation of arrhythmias that can be ablated from this site. (Circ J 2012; 76: 791-800).
Topics: Arrhythmias, Cardiac; Catheter Ablation; Electrocardiography; Humans; Magnetic Resonance Imaging; Sinus of Valsalva; Tomography, X-Ray Computed; Treatment Outcome
PubMed: 22451447
DOI: 10.1253/circj.cj-11-1554 -
JACC. Clinical Electrophysiology Oct 2017This study sought to assess the impact of ablation power and catheter irrigation during clinical radiofrequency ablation using impedance drop.
OBJECTIVES
This study sought to assess the impact of ablation power and catheter irrigation during clinical radiofrequency ablation using impedance drop.
BACKGROUND
In preclinical studies, ablation power and catheter irrigation are determinants of ablation efficacy.
METHODS
Static 30-s left atrial ablations were delivered in patients undergoing their first atrial fibrillation ablation. Impedance drop during ablation (as a measure of efficacy) was compared using the following: the force time integral (FTI); the FTI-P (a cumulative multiple FTI and ablation power), and ablation index (AI), a weighted algorithm including contact force, power, and duration. Comparison was also made between a conventionally irrigated (SmartTouch [ST]) versus surround flow (STSF) contact force-sensing catheter.
RESULTS
We analyzed 1,013 ablations. For both catheters, the Spearman correlation was higher between impedance drop and AI (rho = 0.89 ST, 0.84 STSF) than FTI-P (rho = 0.71 ST, 0.53 STSF) or FTI (rho = 0.77 ST, 0.52 STSF); p < 0.0005 for each. STSF ablations had lower minimum catheter tip temperatures (25°C [interquartile range (IQR): 25°C to 27°C] vs. 35°C [IQR: 34°C to 36°C]; p < 0.005), and lesser impedance drop per FTI or AI (p < 0.005 for both). For STSF, impedance drop plateaued sooner than for ST with respect to FTI (184g.s vs. 463g.s) and AI (370 AI vs. 430 AI).
CONCLUSIONS
AI is a more complete ablation descriptor than is FTI or FTI-P, reflected by a stronger correlation with impedance drop. STSF ablations have lower impedance drop per AI or FTI than ST ablations do, suggesting different targets should be used if ablating guided by impedance drop with STSF. With ST, ablation beyond 430 AI provides minimal additional biophysical efficacy, suggesting an upper limit to use for clinical ablation.
Topics: Aged; Algorithms; Atrial Fibrillation; Biophysical Phenomena; Catheter Ablation; Equipment Design; Female; Humans; Male; Middle Aged; Therapeutic Irrigation; Treatment Outcome
PubMed: 29759489
DOI: 10.1016/j.jacep.2017.03.011 -
Therapeutic Advances in Gastroenterology 2021Insulinoma is the most common neuroendocrine neoplasm of the pancreas, characterised by hypoglycaemic symptoms. Endoscopic ultrasound-guided radiofrequency ablation... (Review)
Review
BACKGROUND
Insulinoma is the most common neuroendocrine neoplasm of the pancreas, characterised by hypoglycaemic symptoms. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) and ethanol ablation (EUS-EA) are novel methods for treating insulinoma.We aimed to perform a systematic review to assess the efficacy and safety of EUS-guided ablation techniques for pancreatic insulinomas.
METHODS
We systematically searched for articles detailing EUS-guided ablations of insulinomas. We performed a qualitative analysis and summarised data on the efficacy and safety of EUS-RFA and EUS-EA techniques.
RESULTS
In total, we identified 35 case reports and case series describing 75 patients with insulinomas treatment with EUS-guided ablation. Twenty-seven patients were treated with EUS-RFA, 47 patients with EUS-EA, and 1 patient received EUS-EA and EUS-RFA in the same session. In total, 84 insulinomas were ablated (EUS-RFA: 31, EUS-EA: 53). Most insulinomas were in the head of the pancreas (40%). The clinical success rate for EUS-guided ablation techniques was 98.5%. The median glucose level was 1.95 (Q1-Q3: 1.69-2.13) mmol/L before ablation compared to 6.20 (Q1-Q3: 5.30-7.05) mmol/L after treatment. The median insulin and C-peptide levels before and after RFA/EA were 230 (Q1-Q2: 120-257) pmol/L and 41 (Q1-Q2 35-42) pmol/L; 2077 (Q1-Q2 1644-2459) pmol/L and 819 (Q1-Q2 696-1072) pmol/L, respectively. There were eleven adverse events: seven abdominal pain, two mild acute pancreatitis, one necrotising acute pancreatitis and one local hematoma. All patients recovered, and there were no periprocedural deaths.
CONCLUSIONS
EUS-guided ablation of insulinoma seems to be a safe and effective treatment and is an alternative to surgical resection in selected cases.
PubMed: 34819995
DOI: 10.1177/17562848211042171 -
Cardiovascular Research Jun 2021Modern cardiac electrophysiology has reported significant advances in the understanding of mechanisms underlying complex wave propagation patterns during atrial... (Review)
Review
Modern cardiac electrophysiology has reported significant advances in the understanding of mechanisms underlying complex wave propagation patterns during atrial fibrillation (AF), although disagreements remain. One school of thought adheres to the long-held postulate that AF is the result of randomly propagating wavelets that wonder throughout the atria. Another school supports the notion that AF is deterministic in that it depends on a small number of high-frequency rotors generating three-dimensional scroll waves that propagate throughout the atria. The spiralling waves are thought to interact with anatomic and functional obstacles, leading to fragmentation and new wavelet formation associated with the irregular activation patterns documented on AF tracings. The deterministic hypothesis is consistent with demonstrable hierarchical gradients of activation frequency and AF termination on ablation at specific (non-random) atrial regions. During the last decade, data from realistic animal models and pilot clinical series have triggered a new era of novel methodologies to identify and ablate AF drivers outside the pulmonary veins. New generation electroanatomical mapping systems and multielectrode mapping catheters, complimented by powerful mathematical analyses, have generated the necessary platforms and tools for moving these approaches into clinical procedures. Recent clinical data using such platforms have provided encouraging evidence supporting the feasibility of targeting and effectively ablating driver regions in addition to pulmonary vein isolation in persistent AF. Here, we review state-of-the-art technologies and provide a comprehensive historical perspective, characterization, classification, and expected outcomes of current mechanism-based methods for AF ablation. We discuss also the challenges and expected future directions that scientists and clinicians will face in their efforts to understand AF dynamics and successfully implement any novel method into regular clinical practice.
Topics: Action Potentials; Animals; Atrial Fibrillation; Catheter Ablation; Heart Atria; Heart Rate; Humans; Recurrence; Treatment Outcome
PubMed: 33744913
DOI: 10.1093/cvr/cvab108 -
Cardiovascular and Interventional... Nov 2021To compare laser ablation (LA) zone dimensions at two predetermined energy parameters to cover a theoretical 10 mm zone + 2 mm margin in a thyroid swine model.
BACKGROUND
To compare laser ablation (LA) zone dimensions at two predetermined energy parameters to cover a theoretical 10 mm zone + 2 mm margin in a thyroid swine model.
METHODS
Approval of the Institutional Animal Care and Use Committee was obtained. After hydrodissection, an ultrasound-guided LA (Elesta Echolaser X4 with Orblaze technology, 1064 nm) was performed in the periphery of the thyroid in 10 swine. Two cohorts were established to ablate a region of 10mm diameter with 2mm margin based on manufacturer's ex vivo data (n= 5 at 3W/1400J and n= 5 at 3W/1800J). The ablation zone was measured on contrast-enhanced computed tomography (CT) and compared to the pathological specimen. Euthanasia was performed 48 hours following ablation.
RESULTS
All ablations in the 3W/1800J group achieved a diameter of 12 mm ± 1 mm in three dimensions. In the 3W/1400J group, 1 ablation reached 12 mm ± 1 mm in 2 dimensions and 4 ablations reached this size in one dimension. Maximum diameter was higher in the 3W/1800J compared to the 3W/1400J group, both on histology (1.46 cm ± 0.05 vs. 1.1 cm ± 0.0, p< 0.01) and CT (1.52 cm ± 0.04 vs. 1.18 cm ± 0.04, p< 0.01). Similar results were obtained regarding volumes, both on histology (1.12 mL ± 0.13 vs. 0.57 mL ± 0.06, p< 0.01) and CT (1.24 mL ± 0.13 vs. 0.59 mL ± 0.07, p< 0.01). Histology showed coagulation necrosis and correlated well with CT measurements.
CONCLUSION
Optimal parameters to obtain a LA zone of 10 mm with 2 mm margin utilizing a single needle are 3W/1800J.
Topics: Ablation Techniques; Animals; Catheter Ablation; Laser Therapy; Swine; Thyroid Gland; Ultrasonography; Ultrasonography, Interventional
PubMed: 34254175
DOI: 10.1007/s00270-021-02915-0 -
Current Cardiology Reviews Nov 2012Atrial fibrillation (AF) ablation has evolved to the treatment of choice for patients with drug-resistant and symptomatic AF. Pulmonary vein isolation at the ostial or... (Review)
Review
Atrial fibrillation (AF) ablation has evolved to the treatment of choice for patients with drug-resistant and symptomatic AF. Pulmonary vein isolation at the ostial or antral level usually is sufficient for treatment of true paroxysmal AF. For persistent AF ablation, drivers and perpetuators outside of the pulmonary veins are responsible for AF maintenance and have to be targeted to achieve satisfying arrhythmia-free success rate. Both complex fractionated atrial electrogram (CFAE) ablation and linear ablation are added to pulmonary vein isolation for persistent AF ablation. Nevertheless, ablation failure and necessity of repeat ablations are still frequent, especially after persistent AF ablation. Pulmonary vein reconduction is the main reason for arrhythmia recurrence after paroxysmal and to a lesser extent after persistent AF ablation. Failure of persistent AF ablation mostly is a consequence of inadequate trigger ablation, substrate modification or incompletely ablated or reconducting linear lesions. In this review we will discuss these points responsible for AF recurrence after ablation and review current possibilities on how to overcome these limitations.
Topics: Angioplasty, Balloon, Coronary; Atrial Fibrillation; Cardiac Catheters; Catheter Ablation; Electrophysiologic Techniques, Cardiac; Humans; Magnetics; Pulmonary Veins; Robotics
PubMed: 22920482
DOI: 10.2174/157340312803760802