Ripple-Mapping for the Detection of Long Duration Action Potential Areas in Patients with Brugada Syndrome

Providencia, R.; Cavaco, D.; Carmo, P.; Pisani, C.; Costa, F. M.; Faustino, M.; Morgado, F.; Lambiase, P. D.; Scanavacca, M.; Adragao, P.

doi:10.1101/263145

bioRxiv · 10.1101/263145

Ripple-Mapping for the Detection of Long Duration Action Potential Areas in Patients with Brugada Syndrome

Providencia, R.·Cavaco, D.·Carmo, P.·Pisani, C.·Costa, F. M.·Faustino, M.·Morgado, F.·Lambiase, P. D.·Scanavacca, M.·Adragao, P.

View original source ↗Export metadata ↓

Abstract

PurposeCatheter ablation has been recently utilised in patients with Brugada syndrome to prevent ventricular arrhythmias. We hypothesized whether a mapping algorithm \"Ripple-mapping\" would be able to rapidly identify the areas of long-duration multicomponent electrograms which constitute the targets for ablation for an automated strategy.\n\nMethodsRipple-Mapping analysis was performed in all patients undergoing catheter ablation of Brugada syndrome in 2 centers. The activity propagation pattern determined by Ripple-Mapping was assessed, and areas of long duration potentials identified by visual inspection. The area of interest with long-duration potentials was correlated with the location of the ablation lesions.\n\nResultsDetection of long duration potentials was possible in all four patients in this analysis. Points marking the ablation area in 2 patients were a perfect match to abnormal areas identified by Ripple-mapping. However, in 2 patients Ripple-mapping identified additional sites of long duration potentials which were not ablated. Acute and mid-term normalization of the ECG pattern was observed in three patients, and all these were free from arrhythmia relapse during a 10.3{+/-}3.2 months follow-up. In one patient, who had no ECG normalization and had arrhythmia relapse, the ablated area corresponded to <25% of the Ripple-map region of interest.\n\nConclusionsThis study shows the potential use of Ripple-mapping for identifying areas of long duration multicomponent electrograms in patients with Brugada syndrome and recurrent ventricular arrhythmias. This technique enables the rapid definition of an area of interest which should then be validated by the operator before performing ablation with an end-point of ECG normalisation.

Explore related subjects

clinical trials Preprint

Keep this discovery

BibTeX RIS

Providencia, R., Cavaco, D., Carmo, P., Pisani, C., Costa, F. M., Faustino, M., Morgado, F., Lambiase, P. D., Scanavacca, M., Adragao, P.. 2018-02-19. Ripple-Mapping for the Detection of Long Duration Action Potential Areas in Patients with Brugada Syndrome. https://doi.org/10.1101/263145

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2018

Multi-Center Study of Resectable Lung Lesions by Ultra-Deep Sequencing of Targeted Genes in Plasma Cell-Free DNA to Assess Nodule Malignancy and Detect Lung Cancers

BACKGROUNDEarly detection of lung cancer to allow curative treatment remains challenging. Cell-free circulating tumor DNA (ctDNA) analysis may aid in malignancy assessment and early cancer diagnosis of lung nodules found in screening imagery.\n\nMETHODSThe multi-center clinical study enrolled 192 patients with operable occupying lung diseases. Plasma ctDNA, white blood cell genomic DNA (gDNA) and tumor tissue gDNA of each patient were analyzed by ultra-deep sequencing to an average of 35,000X of the coding regions of 65 lung cancer-related genes.\n\nRESULTSThe cohort consists of a quarter of benign lung diseases and three quarters of cancer patients with all histopathology subtypes. 64% of the cancer patients is at Stage I. Gene mutations detection in tissue gDNA and plasma ctDNA results in a sensitivity of 91% and specificity of 88%. When ctDNA assay was used as the test, the sensitivity was 69% and specificity 96%. As for the lung cancer patients, the assay detected 63%, 83%, 94% and 100%, for Stage I, II, III and IV, respectively. In a linear discriminant analysis, combination of ctDNA, patient age and a panel of serum biomarkers boosted the overall sensitivity to 80% at a specificity of 99%. 29 out of the 65 genes harbored mutations in the lung cancer patients with the largest number found in TP53 (30% plasma and 62% tumor tissue samples) and EGFR (20% and 40%, respectively).\n\nCONCLUSIONPlasma ctDNA was analyzed in lung nodule assessment and early cancer detection while an algorithm combining clinical information enhanced the test performance.

clinical trials↗

bioRxiv2018

Bacterial strain displacement in inflammatory bowel diseases after fecal microbiota transplantation

Fecal microbiota transplantation (FMT), which is thought to have the potential to correct dysbiosis of gut microbiota, has recently been used to treat inflammatory bowel disease (IBD). To elucidate the extent and principles of microbiota engraftment in IBD patients after FMT treatment, we conducted an interventional prospective cohort study. The cohort included two categories of patients: (1) patients with moderate to severe Crohns disease (CD) (Harvey-Bradshaw Index [≥] 7, n = 11, and (2) patients with ulcerative colitis (UC) (Montreal classification, S2 and S3, n = 4). All patients were treated with a single FMT (via mid-gut, from healthy donors) and follow-up visits were performed at baseline, 3 days, one week, and one month after FMT (missing time points included). At each follow-up time point, fecal samples of the participants were collected along with their clinical metadata. For comparative analysis, 10 fecal samples from 10 healthy people were included to represent the diversity level of normal gut microbiota. Additionally, the metagenomic data of 25 fecal samples from 5 individuals with metabolic syndrome who underwent autologous FMT treatment were downloaded from a previous published paper to represent natural microbiota shifts during FMT. All fecal samples underwent shotgun metagenomic sequencing. We found that 3 days after FMT, 11 out of 15 recipients were in remission (3 out of 4 UC recipients; 8 out of 11 CD recipients). Generally, bacterial colonization was observed to be lower in CD recipients than in UC recipients at both species and strain levels. Furthermore, across species, different strains displayed disease-specific displacement advantages under two-disease status. Finally, most post-FMT species (> 80%) could be properly predicted (AUC > 85%) using a random forest classification model, with the gut microbiota composition and clinical parameters of pre-FMT recipients acting as the most contributive factors for prediction accuracy.

clinical trials↗

bioRxiv2018

Dosage Matters: A Randomized Controlled Trial of Rehabilitation Dose in the Chronic Phase after Stroke

Background and PurposeFor stroke rehabilitation, task-specific training in animal models and human rehabilitation trials is considered important to trigger inherent neuroplasticity, promote motor learning, and functional recovery. Little is known, however, about what constitutes an effective dosage of therapy.\n\nMethodsThis is a parallel group, four arm, single blind, phase I, randomized control trial of four dosages of upper extremity therapy delivered in an outpatient setting during the chronic phase after stroke. Participants were randomized into groups that varied in total dosage of therapy (i.e., 0, 15, 30, or 60 hours). Seven hundred and four participants were assessed for eligibility, 50 were eligible to enroll, 45 were randomized, 44 participated and 41 completed the study. Planned primary analyses used linear mixed effects regression to model baseline to post-intervention changes in the Motor Activity Log-Quality of Movement rating (MALQ) and the Wolf Motor Function Test (WMFT) time score as a function of therapy dosage. A series of hierarchical models were constructed using the MALQ and WMFT.\n\nResultsWe observed a significant dose response curve: the greater the dosage of training, the greater the change in MALQ, with the dose by week slope parameter of 0.0045 ({Delta}MAL/hour/week; p = 0.0011; 95% CI = [0.0019; 0.0071]). Over the 3 weeks of therapy, this corresponds to a gain of 0.81 in MALQ for the 60 hour dose.\n\nConclusionsFor mild-to-moderately impaired stroke survivors, the dosage of a patient-centered, task specific motor therapy was shown to systematically influence the gain in quality of arm use in the natural environment, but not functional capacity as measured in the laboratory. We highlight the importance of recovery outcomes that capture arm use vs. functional capacity.\n\nClinical Trial RegistrationURL: http://www.clinicaltrials.gov. Unique identifier: NCT 01749358

clinical trials↗