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Pablo Ramos Ardanáz

Publicaciones científicas más recientes (desde 2010)

Autores: Garcia-Bolao, I, (Autor de correspondencia); Ballesteros, Gabriel Alejandro; Ramos, P.; et al.
ISSN 1099-5129  Vol. 21  Nº Supl. 1  2019  págs. i4 - i11
Despite the emerging technical evolution of the last two decades, the primary success rate of single-procedure pulmonary vein isolation (PVI), the cornerstone for any atrial fibrillation ablation procedure, is highly variable ranging from 53% to 92%. The recent development of ultra-high-density electroanatomic mapping systems, capable of acquiring and annotating multiple electrograms, with high spatiotemporal precision, which are processed by automated algorithms to generate activation and substrate maps to support and guide ablation procedures, has opened a new stage in cardiac electrophysiology. In this article, we review the existing evidence on the utility of high-density mapping on catheter-based PVI, the possibility to detect pulmonary vein potentials that remain undetected when using a standard approach and its potential relevance to the clinical outcome, and how this new technology is providing novel pathophysiological insights on complete PVI and atrial fibrillation ablation outcomes.
Autores: Ravassa, S; Ballesteros, Gabriel Alejandro; López, B; et al.
ISSN 0735-1097  Vol. 73  Nº 12  2019  págs. 1398 - 1410
Background A combination of circulating biomarkers associated with excessive myocardial collagen type-I cross-linking or CCL+ (i.e., decreased carboxy-terminal telopeptide of collagen type-I to matrix metalloproteinase-1 ratio) and with excessive myocardial collagen type-I deposition or CD+ (i.e., increased carboxy-terminal propeptide of procollagen type-I) has been described in heart failure (HF) patients and associates with poor outcomes. Objectives The purpose of this study was to investigate whether the CCL+CD+ combination of biomarkers associates with atrial fibrillation (AF). Methods Biomarkers were analyzed in serum samples from 242 HF patients (study 1) and 150 patients referred for AF ablation (study 2). Patients were classified into 3 groups (CCL¿CD¿, CCL+CD¿ or CCL¿CD+, and CCL+CD+) in accordance to biomarker threshold values. Left atrial electroanatomic high-density mapping was performed in 71 patients from study 2. Results In study 1, 53.7% patients had AF at baseline and 19.6% developed AF (median follow-up 5.5 years). Adjusted odds and hazard ratios associated with baseline and new-onset AF, respectively, were both ¿3.3 (p ¿ 0.050) in CCL+CD+ patients compared with CCL¿CD¿ patients, with nonsignificant changes in the other group. In study 2, 29.3% patients had AF recurrence during 1-year post-ablation.
Autores: Ballesteros, Gabriel Alejandro; Ravassa, S; Bragard, Jean René Alfred; et al.
ISSN 1045-3873  Vol. 30  Nº 8  2019  págs. 1231 - 1240
Introduction Ultrahigh-density-voltage mapping (uHD(V)M) is a new tool that can add new insights into the pathophysiology of atrial fibrillation (AF). The aim of this study was to evaluate the performance of uHD(V)M in predicting postablation AF recurrence (AFR). Methods and Results We included 98 consecutive patients undergoing pulmonary vein isolation for AF (40.8% persistent) using an uHD(V)M system and followed for 1 year. The left atrium (LA) mean voltage (V-m) and the V-slope (slope of the voltage histogram calculated by linear interpolation, with the relative frequency on the vertical axis and the bipolar potential on the horizontal axis) were calculated from 12 567 +/- 5486 points per map. Patients with AFR (N = 29) had lower V-m and higher V-slope as compared with patients without AFR (N = 69). Receiver operating characteristic curves identified V-m as the strongest predictor of AFR, with a higher incidence of AFR in patients with V-m 0.758 mV (57.6%) or lower than patients with V-m higher than 0.758 mV (15.4%; P < .0001). Among patients with V-m higher than 0.758 mV, patients with V-slope 0.637 or higher exhibited higher (P = .043) AFR incidence (31.3%) than patients with V-slope lower than 0.637 (10.2%). This classification showed incremental predictive value over relevant covariables. V-m values were lower and V-slope values were higher in patients that progressed from paroxysmal to persistent AF. Patients with V-slope 0.637 or higher had a 14.2% incidence of postablation atypical atrial flutter, whereas patients with V-slope lower than 0.637 did not present this outcome. Conclusions The risk of AFR, atrial flutter, and progression from paroxysmal to persistent AF can be detected by quantitative analysis of LA uHD(V)M identifying diverse patterns of atrial substrate alterations.
Autores: Ruiz-Granell, R., (Autor de correspondencia); Ballesteros, Gabriel Alejandro; Andreu, D.; et al.
ISSN 1099-5129  Vol. 21  Nº 2  2019  págs. 250 - 258
Aims Atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) is usually associated to conduction gaps in pulmonary veins (PVs). Our objective was to characterize gaps in patients with recurrences after a first radiofrequency (RF) or cryoballoon (CB) PVI procedure, using a high-density mapping (HDM) system. Methods and results Fifty patients with AF recurrence after a first PVI procedure (pre-RF 25 patients; pre-CB 25 patients) were included at two centres. Activation map (AM) and voltage map (VM) of the left atrium and PVs were built using the HDM Rhythmia (R) system. Superior PVs were reconnected more frequently in both groups. Right PVs were reconnected more frequently in pre-RF patients. Pre-RF patients had more reconnected veins than pre-CB patients (meanstandard deviation: 3.00 +/- 0.96 vs. 1.88 +/- 1.13; P<0.001) and more gaps (4.84 +/- 2.06 vs. 2.16 +/- 1.49; P<0.001). Gaps in the VM were wider in pre-CB patients (16.5 +/- 9.5mm vs. 12.1 +/- 4.8mm; P=0.006). There was a gap in 179 of the 800 PV segments analysed (22%); 52% were identified in both AM and VM maps; 39% only in the AM and 8% only in the VM. The highest sensitivity and specificity for gap detection was obtained with VM in pre-CB patients and with AM in pre-RF patients. Conclusion In conclusion, HDM seems to be a useful and precise tool to detect conduction gaps after a first PVI procedure. The anatomical pattern and location of gaps depends on the technique used previously, usually being multiple, smaller, and better detected by AM after RF, and fewer, wider, and better detected by VM after CB.
Autores: Ballesteros, Gabriel Alejandro; Ramos, P.; et al.
ISSN 0009-7322  Vol. 137  Nº 7  2018  págs. 743 - 746
Autores: Garcia-Bolao, I, (Autor de correspondencia); Ballesteros, Gabriel Alejandro; Ramos, P.; et al.
ISSN 1099-5129  Vol. 20  Nº Supl. 3  2018  págs. F351 - F358
Aims Maps obtained by means of electroanatomic high-density mapping (HDM) systems have shown their use in the identification of conduction gaps in experimental atrial linear lesion models. The objective of this study was to assess the use of HDM in the recognition of reconnection gaps in pulmonary veins (PV) in redo atrial fibrillation (AF) ablation procedures. Methods and results One hundred and eight patients were included in a non-randomized study that assessed the recognition of reconnection gaps in PV by means of HDM compared to a control group that received conventional non-fluoroscopic guidance with a circular multipolar catheter (CMC). Among the HDM group, adequate recognition of reconnection gaps was obtained in 60.99% of the reconnected PVs (86 of 141), a figure significantly higher than that achieved with analysis of CMC recorded signals (39.66%, 48 of 121; P = 0.001). The number of applications and total radiofrequency time were also significantly lower in the HDM group (12.46 +/- 6.1 vs. 15.63 +/- 7.7 and 7.61 +/- 3 vs. 9.29 +/- 5; P = 0.02, and P = 0.03, respectively). At the 6-month follow-up, no statistically significant differences were found in recurrence of AF or any other atrial tachycardia between the HDM group (8 patients, 14.8%) and the control group in (16 patients, 29.6%; P = 0.104). Conclusion An analysis of the high-density activation maps allows greater precision in the identification of reconnection gaps in PV, which results in lower radiofrequency time for the new isolation.
Autores: Ballesteros, Gabriel Alejandro, (Autor de correspondencia); Ramos, P.; et al.
ISSN 0009-7322  Vol. 138  Nº 4  2018  págs. 439 - 440
Autores: Ballesteros, Gabriel Alejandro; Ramos, P.; et al.
ISSN 1885-5857  Vol. 70  Nº 9  2017  págs. 706 - 712
INTRODUCTION AND OBJECTIVES: Rhythmia is a new nonfluoroscopic navigation system that is able to create high-density electroanatomic maps. The aim of this study was to describe the acute outcomes of atrial fibrillation (AF) ablation guided by this system, to analyze the volume provided by its electroanatomic map, and to describe its ability to locate pulmonary vein (PV) reconnection gaps in redo procedures. METHODS: This observational study included 62 patients who underwent AF ablation with Rhythmia compared with a retrospective cohort who underwent AF ablation with a conventional nonfluoroscopic navigation system (Ensite Velocity). RESULTS: The number of surface electrograms per map was significantly higher in Rhythmia procedures (12 125 ± 2826 vs 133 ± 21 with Velocity; P < .001), with no significant differences in the total procedure time. The Orion catheter was placed for mapping in 99.5% of PV (95.61% in the control group with a conventional circular mapping catheter; P = .04). There were no significant differences in the percentage of PV isolation between the 2 groups. In redo procedures, an ablation gap could be identified on the activation map in 67% of the reconnected PV (40% in the control group; P = .042). The measured left atrial volume was lower than that calculated by computed tomography (109.3 v 15.2 and 129.9 ± 13.2 mL, respectively; P < .001). There were no significant differences in the number of complications. CONCLUSIONS: The Rhythmia system is effective for AF ablation procedures, with procedure times and safety profiles similar to conventional nonfluoroscopic navigation systems. In redo procedures, it appears to be more effective in identifying reconnected PV conduction gaps.
Autores: Ballesteros, Gabriel Alejandro; Ramos, P.; et al.
ISSN 1885-5857  Vol. 70  Nº 7  2017  págs. 598 - 600
Autores: Ballesteros, Gabriel Alejandro; Ramos, P.; et al.
ISSN 0147-8389  Vol. 40  Nº 5  2017  págs. 545 - 550
BackgroundFirst description of a technique for left atrium transseptal puncture (TSP) with minimal radiation exposure by using the nonfluoroscopic MediGuide tracking system (MG; St. Jude Medical, St. Paul, MN, USA) without the assistance of intracardiac echocardiography. MethodsThis study included 31 consecutive patients with atrial fibrillation undergoing an MG-assisted percutaneous catheter ablation procedure. A Brockenbrough transseptal needle (BRK) is connected to a standard pressure transducer through a two-input valve. Then, an MG-enabled guidewire is inserted so that its tip exactly matches the BRK's distal tip. After the acquisition of two short radioscopic cine-loops we are able to trace the needle tip on the MG screen, performing the usual TSP maneuver but without fluoroscopy. Successful left atrium access is confirmed by noticing the change in the pressure curve and by advancing the guidewire into the left pulmonary veins. As a control group, 31 matched patients who underwent atrial fibrillation ablation with fluoroscopically guided, pressure-monitored TSP were included. ResultsSixty-two MG-assisted TSP attempts were performed; all but two were successfully accomplished without changing to the conventional technique (96.7%). The mean total fluoroscopy time, until the double transseptal access was performed, was 26.65 37.97 seconds in the MG group and 129.13 +/- 37.77 seconds in the conventional-TSP group (P < 0.001). No major complications occurred during any of the procedures. ConclusionThis new technique for TSP using MG is feasible and can be performed with minimal radiation exposure without the need for additional imaging techniques, achieving a significant reduction of fluoroscopy time.
Autores: Calvo, N; Ramos, P.; S; et al.
ISSN 1099-5129  Vol. 18  Nº 1  2016  págs. 57-63
A history of ¿2000 h of vigorous endurance training, tall stature, abdominal obesity, and OSA are frequently encountered as risk factors in patients with Ln-AF. Fewer than 2000 total hours of high-intensity endurance training associates with reduced Ln-AF risk.
Autores: N; V; m; et al.
ISSN 0300-2896  Vol. 52  Nº 1  2016  págs. 17-23
CPAP therapy only partially improves heart rate variability, and exclusively during waking hours, and reduces incidence of atrial tachycardia, both of which can influence cardiovascular morbidity and mortality in sleep apnea¿hypopnea syndrome patients.
Autores: Garcia-Bolao, I; Calvo, N; et al.
ISSN 1941-6911  Vol. 8  Nº 5  2016  págs. 61-66
Autores: Ramos, P.; c; m; et al.
ISSN 1465-9921  Vol. 15  2014  págs. 54
OSA induces selective atrial fibrosis in a chronic murine model, which can be mediated in part by the systemic and local inflammation and by decreased collagen-degradation. MSCs transplantation prevents atrial fibrosis, suggesting that these stem cells could counterbalance inflammation in OSA.
Autores: e; e; f; et al.
ISSN 2047-9980  Vol. 3  Nº 5  2014  págs. e000877
The linear block at the LA roof is not associated with an improved clinical outcome compared with PV isolation alone.
Autores: Calvo, N; f; e; et al.
ISSN 0167-5273  Vol. 168  Nº 4  2013  págs. 4093-7
The study groups included 659 consecutive patients undergoing CA between 2003 and 2011: TMP group (n = 61), HF group (n = 36) and control group (n = 562). Compared to controls, patients with TMP were younger, had a shorter AF course and more often had persistent AF. Regarding echocardiographic parameters, the TMP group had lower LVEF (40% vs. 62%, P < 0.05), larger left atrial diameter (LAD: 46 vs. 41 mm, P < 0.05) and LV end-diastolic diameter (LVEDD: 55 vs. 51 mm, P < 0.05) compared to controls, with significant improvement at six-month follow-up, including those patients with AF recurrence. The probability of being arrhythmia-free did not differ between the TMP group and the other groups after a first or last procedure. The only independent predictor of AF recurrence was LAD. CONCLUSIONS: Patients with tachycardiomyopathy secondary to AF benefit from CA, with a significant improvement in LVEF, LVEDD and LAD. The outcome after CA of this group did not differ from patients with no structural cardiomyopathy.