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JACC. Clinical Electrophysiology Oct 2019This study aimed to develop a novel premature ventricular contraction (PVC) mapping method to predict PVC origins in whole ventricles by merging a magnetocardiography...
OBJECTIVES
This study aimed to develop a novel premature ventricular contraction (PVC) mapping method to predict PVC origins in whole ventricles by merging a magnetocardiography (MCG) image with a cardiac computed tomography (CT) image.
BACKGROUND
MCG can noninvasively discriminate PVCs originating from the aortic sinus cusp from those originating from the right ventricular outflow tract.
METHODS
This study was composed of 22 candidates referred for catheter ablation of idiopathic PVCs. MCG and CT were performed the same day before ablation. Estimated origins by MCG-CT imaging using the recursive null steering spatial filter algorithm were compared with origins determined by electroanatomic mapping (CARTO, Biosense Webster, Inc., Diamond Bar, California) during the ablation procedure. Radiopaque acrylic markers for the CT scan and coil markers generating a weak magnetic field during MCG measurements were used as reference markers to merge the 2 images 3-dimensionally.
RESULTS
PVC origins were determined by endocardial and epicardial mapping and ablation results in 18 (86%) patients (right ventricular outflow tract in 10 patients, aortic sinus cusp in 2 patients, interventricular septum in 1 patient, near His bundle in 1 patient, right ventricular free wall in 1 patient, and left ventricular free wall in 3 patients). Estimated origins by MCG-CT imaging matched the origins determined during the procedure in 94% (17 of 18) of patients, whereas the electrocardiography algorithms were accurate in only 56% (10 of 18). Discrimination of an epicardium versus an endocardium or right- versus left-sided septum was successful in 3 of 4 patients (75%).
CONCLUSIONS
The diagnostic accuracy of noninvasive MCG-CT mapping was high enough to allow clinical use to predict the site of PVC origins in the whole ventricles.
Topics: Adult; Aged; Aged, 80 and over; Bundle-Branch Block; Catheter Ablation; Female; Heart Ventricles; Humans; Imaging, Three-Dimensional; Magnetocardiography; Male; Middle Aged; Multimodal Imaging; Sinus of Valsalva; Tomography, X-Ray Computed; Treatment Outcome; Ventricular Premature Complexes
PubMed: 31648739
DOI: 10.1016/j.jacep.2019.06.010 -
ELife Mar 2023Long noncoding RNAs (lncRNAs) are emerging as critical regulators of heart physiology and disease, although the studies unveiling their modes of action are still limited...
Long noncoding RNAs (lncRNAs) are emerging as critical regulators of heart physiology and disease, although the studies unveiling their modes of action are still limited to few examples. We recently identified pCharme, a chromatin-associated lncRNA whose functional knockout in mice results in defective myogenesis and morphological remodeling of the cardiac muscle. Here, we combined Cap-Analysis of Gene Expression (CAGE), single-cell (sc)RNA sequencing, and whole-mount in situ hybridization analyses to study pCharme cardiac expression. Since the early steps of cardiomyogenesis, we found the lncRNA being specifically restricted to cardiomyocytes, where it assists the formation of specific nuclear condensates containing MATR3, as well as important RNAs for cardiac development. In line with the functional significance of these activities, pCharme ablation in mice results in a delayed maturation of cardiomyocytes, which ultimately leads to morphological alterations of the ventricular myocardium. Since congenital anomalies in myocardium are clinically relevant in humans and predispose patients to major complications, the identification of novel genes controlling cardiac morphology becomes crucial. Our study offers unique insights into a novel lncRNA-mediated regulatory mechanism promoting cardiomyocyte maturation and bears relevance to Charme locus for future theranostic applications.
Topics: Animals; Humans; Mice; Cell Differentiation; Heart Ventricles; Myocardium; Myocytes, Cardiac; Nuclear Matrix-Associated Proteins; RNA, Long Noncoding; RNA-Binding Proteins
PubMed: 36877136
DOI: 10.7554/eLife.81360 -
Heart Rhythm Jan 2019Bilateral thoracoscopic stellectomy has antiarrhythmic effects, but the procedure is invasive with associated morbidity. Sympathetic nerves from both stellate ganglia...
BACKGROUND
Bilateral thoracoscopic stellectomy has antiarrhythmic effects, but the procedure is invasive with associated morbidity. Sympathetic nerves from both stellate ganglia form the deep cardiac plexus (CP) in the aortopulmonary window, anterior to the trachea.
OBJECTIVE
The purpose of this study was to demonstrate a novel and minimally invasive transtracheal approach to block the CP in porcine models.
METHODS
In 12 Yorkshire pigs, right (RSG) and left (LSG) stellate ganglia were electrically stimulated and sympathetic baseline response recorded (hemodynamic parameters and T-wave pattern). Aortopulmonary window was accessed transtracheally with endobronchial ultrasound guidance, and local stimulation of CP confirmed the location. Injection of 1% lidocaine (n = 10) or saline solution (n = 2) was performed, and RSG and LSG responses were re-evaluated and compared with baseline.
RESULTS
Transtracheal lidocaine injection into the CP successfully blocked bilateral sympathetic induced changes (%) in T-wave amplitude (282.8% ± 152.2% vs 20.1% ± 16.5%; P <.001 [LSG]; 338.9% ± 189.8% vs 28% ± 18.3%; P <.001 [RSG]), Tp-Te interval (87.9% ± 37.2% vs 6.9% ± 6.7%; P <.001 [LSG]; 32.6% ± 27.4% vs 6.9% ± 4.7%; P <.035 [RSG]), and left ventricular dP/dT (148.3% ± 108.5% vs 16.5% ± 13.4%; P <.001 [LSG]; 243.1% ± 105.2% vs 19.0% ± 12.4%; P <.001 [RSG]). RSG-induced elevations of systemic, left ventricular, and pulmonary arterial pressures were blocked by lidocaine injection into CP (P <.005 for all comparisons). Stellate ganglia response was not affected in sham studies. No complications were observed during the procedures.
CONCLUSION
Minimally invasive transtracheal injection of lidocaine into the CP blocked the sympathetic response of either RSG and LSG. Transtracheal assessment of CP may allow for minimally invasive and selective ablation of cardiac innervation, extending the cardiac sympathectomy denervation benefits to those not suitable for surgery.
Topics: Animals; Autonomic Nerve Block; Disease Models, Animal; Electrocardiography; Endosonography; Female; Heart Conduction System; Heart Ventricles; Stellate Ganglion; Swine; Tachycardia, Ventricular; Trachea; Transcutaneous Electric Nerve Stimulation
PubMed: 30075280
DOI: 10.1016/j.hrthm.2018.07.037 -
Journal of the American College of... Apr 2018Guidelines recommend the use of implanted cardioverter-defibrillators in patients with Brugada syndrome and induced ventricular tachyarrhythmias, but there is no...
BACKGROUND
Guidelines recommend the use of implanted cardioverter-defibrillators in patients with Brugada syndrome and induced ventricular tachyarrhythmias, but there is no evidence supporting it.
OBJECTIVES
This prospective registry study was designed to explore clinical and electrophysiological predictors of malignant ventricular tachyarrhythmia inducibility in Brugada syndrome.
METHODS
A total of 191 consecutive selected patients with (group 1; n = 88) and without (group 2; n = 103) Brugada syndrome-related symptoms were prospectively enrolled in the registry. Patients underwent electrophysiological study and substrate mapping or ablation before and after ajmaline testing (1 mg/kg/5 min).
RESULTS
Overall, before ajmaline testing, 53.4% of patients had ventricular tachyarrhythmia inducibility, which was more frequent in group 1 (65.9%) than in group 2 (42.7%; p < 0.001). Regardless of clinical presentation, larger substrates with more fragmented long-duration ventricular potentials were found in patients with inducible arrhythmias than in patients without inducible arrhythmias (p < 0.001). One extrastimulus was used in more extensive substrates (median 13 cm; p < 0.001), and ventricular fibrillation was the more frequently induced rhythm (p < 0.001). After ajmaline, patients without arrhythmia inducibility had arrhythmia inducibility without a difference in substrate characteristics between the 2 groups. The substrate size was the only independent predictor of inducibility (odds ratio: 4.51; 95% confidence interval: 2.51 to 8.09; p < 0.001). A substrate size of 4 cm best identified patients with inducible arrhythmias (area under the curve: 0.98; p < 0.001). Substrate ablation prevented ventricular tachyarrhythmia reinducibility.
CONCLUSIONS
In Brugada syndrome dynamic substrate variability represents the pathophysiological basis of lethal ventricular tachyarrhythmias. Substrate size is independently associated with arrhythmia inducibility, and its determination after ajmaline identifies high-risk patients missed by clinical criteria. Substrate ablation is associated with electrocardiogram normalization and not arrhythmia reinducibility. (Epicardial Ablation in Brugada Syndrome [BRUGADA_I]; NCT02641431; Epicardial Ablation in Brugada Syndrome: An Extension Study of 200 BrS Patients; NCT03106701).
Topics: Adult; Brugada Syndrome; Electrocardiography; Epicardial Mapping; Female; Heart Ventricles; Humans; Male; Middle Aged; Prospective Studies
PubMed: 29650119
DOI: 10.1016/j.jacc.2018.02.022 -
JACC. Clinical Electrophysiology Jan 2019This study examined radiofrequency catheter ablation (RFCA) lesions within and around scar by cardiac magnetic resonance (CMR) imaging and histology.
OBJECTIVES
This study examined radiofrequency catheter ablation (RFCA) lesions within and around scar by cardiac magnetic resonance (CMR) imaging and histology.
BACKGROUND
Substrate modification by RFCA is the cornerstone therapy for ventricular arrhythmias. RFCA in scarred myocardium, however, is not well understood.
METHODS
We performed electroanatomic mapping and RFCA in the left ventricles of 8 swine with myocardial infarction. Non-contrast-enhanced T-weighted (T1w) and contrast-enhanced CMR after RFCA were compared with gross pathology and histology.
RESULTS
Of 59 lesions, 17 were in normal myocardium (voltage >1.5 mV), 21 in border zone (0.5 to 1.5 mV), and 21 in scar (<0.5 mV). All RFCA lesions were enhanced in T1w CMR, whereas scar was hypointense, allowing discrimination among normal myocardium, scar, and RFCA lesions. With contrast-enhancement, lesions and scar were similarly enhanced and not distinguishable. Lesion width and depth in T1w CMR correlated with necrosis in pathology (both; r = 0.94, p < 0.001). CMR lesion volume was significantly different in normal myocardium, border zone, and scar (median: 397 [interquartile range (IQR): 301 to 474] mm, 121 [IQR: 87 to 201] mm, 66 [IQR: 33 to 123] mm, respectively). RFCA force-time integral, impedance, and voltage changes did not correlate with lesion volume in border zone or scar. Histology showed that ablation necrosis extended into fibrotic tissue in 26 lesions and beyond in 14 lesions. In 7 lesions, necrosis expansion was blocked and redirected by fat.
CONCLUSIONS
T1w CMR can selectively enhance necrotic tissue in and around scar and may allow determination of the completeness of ablation intra- and post-procedure. Lesion formation in scar is affected by tissue characteristics, with fibrosis and fat acting as thermal insulators.
Topics: Animals; Arrhythmias, Cardiac; Cardiac Imaging Techniques; Catheter Ablation; Cicatrix; Electrophysiologic Techniques, Cardiac; Heart Ventricles; Magnetic Resonance Imaging; Myocardial Infarction; Swine
PubMed: 30678791
DOI: 10.1016/j.jacep.2018.11.001 -
JACC. Clinical Electrophysiology Oct 2017This study evaluated the use of half-normal saline (HNS) as the radiofrequency ablation (RFA) cooling irrigant.
OBJECTIVES
This study evaluated the use of half-normal saline (HNS) as the radiofrequency ablation (RFA) cooling irrigant.
BACKGROUND
Some instances of ventricular arrhythmia may originate deep within myocardium and can be refractory to standard ablation using open irrigated RFA. Recent data suggest that deeper ablation lesions can be created by decreasing the irrigant ionic concentration delivered through open irrigated RFA than by using normal saline (NS).
METHODS
Bovine myocardium was placed in a circulating saline bath. Two RFA catheters were oriented across from each other, with myocardium in between. Sequential unipolar HNS-irrigated RFA was performed and compared to bipolar ablation by using NS or HNS. Unipolar HNS ablation of the ventricles in a porcine model was performed and compared to ablation using NS.
RESULTS
Sequential ex vivo unipolar RFA with HNS produced larger lesions than sequential unipolar RFA with NS and produced lesions of similar size to those created with bipolar RFA using NS. Ex vivo bipolar RFA using HNS created the largest lesions. In vivo unipolar HNS ablation in porcine endocardium created larger lesion volumes, 152.9 ± 29.2 μl, compared to 94.7 ± 33.4 μl for unipolar ablation using NS.
CONCLUSIONS
By decreasing ionic concentration and charge density in RFA using HNS instead of NS irrigant, larger ablation lesions can be created and are similar in size to lesions created using bipolar ablation. This may be a useful ablation strategy for deep myocardial circuits refractory to standard ablation. Further studies are needed to evaluate this novel RFA strategy.
Topics: Animals; Arrhythmias, Cardiac; Biophysical Phenomena; Catheter Ablation; Cattle; Electrodes; Endocardium; Equipment Design; Heart Ventricles; Models, Animal; Saline Solution; Therapeutic Irrigation
PubMed: 29759492
DOI: 10.1016/j.jacep.2017.03.006 -
The Journal of International Medical... Jan 2020We herein describe a 33-year-old woman with a mechanical aortic and mitral valve who developed repetitive monomorphic ventricular tachycardia with unstable hemodynamics.... (Review)
Review
We herein describe a 33-year-old woman with a mechanical aortic and mitral valve who developed repetitive monomorphic ventricular tachycardia with unstable hemodynamics. Catheter ablation by direct puncture at the left ventricular apex through a minithoracotomy successfully terminated the ventricular tachycardia, which had originated from the apical-septal endocardium in the left ventricle, despite the hindrance to routine access. No procedure-related complications or recurrence of the clinical ventricular tachycardia developed during a 66-month follow-up, demonstrating that endocardial ablation through direct cardiac cavity puncture can be considered in select cases.
Topics: Adult; Electrocardiography; Female; Heart Valve Prosthesis; Heart Ventricles; Humans; Tachycardia, Ventricular
PubMed: 31996068
DOI: 10.1177/0300060519897667 -
Journal of Cardiology May 2023The neuromodulation effect after ventricular arrhythmia (VA) ablation is unclear. The study aimed to investigate skin sympathetic nerve activity (SKNA) changes in...
BACKGROUND
The neuromodulation effect after ventricular arrhythmia (VA) ablation is unclear. The study aimed to investigate skin sympathetic nerve activity (SKNA) changes in patients receiving catheter ablations for idiopathic VA.
METHODS
Of 43 patients with drug-refractory symptomatic VA receiving ablation, SKNA was continuously recorded for 10 min during resting from electrocardiogram lead I configuration and bipolar electrodes on the right arm 1 day before and 1 day after ablation.
RESULTS
Twenty-two patients with acute procedure success and no recurrence during follow-ups were classified as sustained success group (group 1). Other 21 patients were classified as failed ablation group (group 2). Baseline SKNA showed no significant difference between the two groups. Post-ablation SKNA in group 2 was significantly higher than in group 1. In patients with ablation involved right ventricular outflow tract (RVOT), the post-ablation SKNA was also significantly higher in group 2. In contrast, there was no difference in post-ablation SKNA between groups in patients receiving non-RVOT ablation.
CONCLUSION
The neuromodulation response after RVOT ablation may correspond to the sympathetic nerve distribution at RVOT. Augmentation of sympathetic activity after VA ablation indicates an unsuccessful VA suppression, especially in patients receiving ablation of RVOT VA.
Topics: Humans; Arrhythmias, Cardiac; Heart Ventricles; Catheter Ablation; Sympathetic Nervous System; Skin; Electrocardiography; Tachycardia, Ventricular; Treatment Outcome
PubMed: 36372323
DOI: 10.1016/j.jjcc.2022.11.003 -
Cardiology Journal 2022
Topics: Arrhythmias, Cardiac; Catheter Ablation; Electrocardiography; Fluoroscopy; Heart Ventricles; Humans; Tachycardia, Ventricular; Treatment Outcome
PubMed: 34671965
DOI: 10.5603/CJ.a2021.0131 -
Europace : European Pacing,... Dec 2023
Topics: Humans; Brugada Syndrome; Defibrillators, Implantable; Standard of Care; Heart Ventricles; Arrhythmias, Cardiac; Catheter Ablation
PubMed: 38252938
DOI: 10.1093/europace/euae020