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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 -
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 -
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 -
Sensors (Basel, Switzerland) May 2022Microwave ablation systems allow for performing tumoral destruction in oncology. The objective of this study was to assess the early response and reliability of the...
Microwave ablation systems allow for performing tumoral destruction in oncology. The objective of this study was to assess the early response and reliability of the microwave ablation zone size at one month for liver, kidney and lung lesions, as compared to the manufacturer's charts. Patients who underwent microwave ablation with the Emprint ablation system for liver, kidney and lung lesions between June 2016 and June 2018 were retrospectively reviewed. Local response and ablation zone size (major, , and minor, , axes) were evaluated on the one-month follow-up imaging. Results were compared to the manufacturers' charts using the Bland-Altman analysis. Fifty-five patients (mean age 68 ± 11 years; 95 lesions) were included. The one-month complete response was 94%. Liver ablations showed a good agreement with subtle, smaller ablation zones (: -2 ± 5.7 mm; : -5.2 ± 5.6 mm). Kidney ablations showed a moderate agreement with larger ablations for L (: 8.69 ± 7.94 mm; : 0.36 ± 4.77 mm). Lung ablations showed a moderate agreement, with smaller ablations for l (: -5.45 ± 4.5 mm; : -9.32 ± 4.72 mm). With 94% of early complete responses, the system showed reliable ablations for liver lesions, but larger ablations for kidney lesions, and smaller for lung lesions.
Topics: Aged; Humans; Kidney; Liver; Lung; Microwaves; Middle Aged; Reproducibility of Results; Retrospective Studies
PubMed: 35684594
DOI: 10.3390/s22113973 -
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 -
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 -
IEEE Transactions on Ultrasonics,... Sep 2021A 34-mm aperture transducer was designed and tested for proof of concept to ablate tissues using an endocavity histotripsy device. Several materials and two drivers were...
A 34-mm aperture transducer was designed and tested for proof of concept to ablate tissues using an endocavity histotripsy device. Several materials and two drivers were modeled and tested to determine an effective piezoelectric-matching layer combination and driver design. The resulting transducer was fabricated using 1.5 MHz porous PZT and PerFORM 3-D printed acoustic lenses and was driven with a multicycle class-D amplifier. The lower frequency, compared to previously developed small form factor histotripsy transducers, was selected to allow for more efficient volume ablation of tissue. The transducer was characterized and tested by measuring pressure field maps in the axial and lateral planes and pressure output as a function of driving voltage. The axial and lateral full-width-half-maximums of the focus were found to be 6.1 and 1.1 mm, respectively. The transducer was estimated to generate 34.5-MPa peak negative focal pressure with a peak-to-peak driving voltage of 1345 V. Performance testing was done by ablating volumes of bovine liver tissues ( n = 3 ). The transducer was found to be capable of ablating tissues at its full working distance of 17 mm.
Topics: Acoustics; Animals; Cattle; Equipment Design; High-Intensity Focused Ultrasound Ablation; Liver; Transducers
PubMed: 33507869
DOI: 10.1109/TUFFC.2021.3055138 -
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 Feb 2020This study sought to examine clinical characteristics of procedural and long-term outcomes in patients undergoing catheter ablation (CA) of outflow tract ventricular...
OBJECTIVES
This study sought to examine clinical characteristics of procedural and long-term outcomes in patients undergoing catheter ablation (CA) of outflow tract ventricular arrhythmias (OT-VAs) over 16 years.
BACKGROUND
CA is an effective treatment strategy for OT-VAs.
METHODS
Patients undergoing CA for OT-VAs from 1999 to 2015 were divided into 3 periods: 1999 to 2004 (early), 2005 to 2010 (middle), and 2011 to 2015 (recent). Successful ablation site (right ventricular OT, aortic cusps/left ventricular OT, or coronary venous system/epicardium), VA morphology (right bundle branch block or left bundle branch block), and acute and clinical success rates were assessed.
RESULTS
Six hundred eighty-two patients (336 female) were included (early: n = 97; middle: n = 204; recent: n = 381). Over time there was increase in use of irrigated ablation catheters and electroanatomic mapping, and more VAs were ablated from the aortic cusp/left ventricular OT or coronary venous system/epicardium (14% vs. 45% vs. 56%; p < 0.0001). Acute procedural success was achieved in 585 patients (86%) and was similar between groups (82% vs. 84% vs. 88%; p = 0.27). Clinical success was also similar between groups (86% vs. 87% vs. 88%; p = 0.94), but more patients in earlier periods required repeat ablation (18% vs. 17% vs. 9%; p = 0.02). Overall complication rate was 2% (similar between groups).
CONCLUSIONS
Over a 16-year period there was an increase in patients undergoing CA for OT-VTs, with more ablations performed at non-right ventricular outflow tract locations using electroanatomic mapping and irrigated-tip catheters. Over time, single procedure success has improved and complications have remained limited.
Topics: Adult; Arrhythmias, Cardiac; Bundle-Branch Block; Catheter Ablation; Female; Heart Ventricles; Humans; Male; Middle Aged; Retrospective Studies; Treatment Outcome
PubMed: 32081227
DOI: 10.1016/j.jacep.2019.10.004