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- Does a left common pulmonary trunk anatomy represent a real limitation for atrial fibrillation cryoablation success?Publication . Brito, Joana; Rodrigues, Tiago; António, Pedro Silvério; Ferreira, Afonso Nunes; Lima Da Silva, Gustavo; Bernardes, Ana; Barreiros, Céu; Ribeiro, João; Carpinteiro, Luís; Cortez-Dias, Nuno; Pinto, Fausto J.; De Sousa, JoãoCryoballoon ablation (CBA) has been increasingly used for atrial fbrillation (AF) ablation. The presence of pulmonary vein (PV) anatomical variants, particularly left common pulmonary trunk (LCPT), may limit the cryoballoon adaptability and performance. To evaluate the impact of the presence of LCPT in CBA, we compared the success, safety, and procedure characteristics in consecutive patients referred for a frst-ever PVI attempt, irrespective of AF type and PV anatomy.
- Chronic thromboembolic pulmonary hypertension: initial experience of patients undergoing pulmonary thromboendarterectomyPublication . Plácido, Rui; Guimarães, Tatiana; Jenkins, David; Cortez-Dias, Nuno; Couto Pereira, Sara Cristina; Campos, Paula; Mineiro, Ana; Lousada, Nuno; Martins, Susana; Moreira, Susana; Dias, Ana Rocha; Resende, Catarina; Vieira, Rita; Pinto, Fausto J.Introduction and objectives: Pulmonary endarterectomy (PEA) is a potentially curative procedure in patients with chronic thromboembolic pulmonary hypertension (CTEPH). This study reports the initial experience of a Portuguese PH center with patients undergoing PEA at an international surgical reference center. Methods: Prospective observational study of consecutive CTEPH patients followed at a national PH center, who underwent PEA at an international surgical reference center between October 2015 and March 2019. Clinical, functional, laboratory, imaging and hemodynamic parameters were obtained in the 12 months preceding the surgery and repeated between four and six months after PEA. Results: 27 consecutive patients (59% female) with a median age of 60 (49-71) years underwent PEA. During a median follow-up of 34 (21-48) months, there was an improvement in functional class in all patients, with only one cardiac death. From a hemodynamic perspective, there was a reduction in mean pulmonary artery pressure from 48 (42-59) mmHg to 26 (22-38) mmHg, an increase in cardiac output from 3.3 (2.9-4.0) L/min to 4.9 (4.2-5.5) L/min and a reduction in pulmonary vascular resistance from 12.1 (7.2-15.5) uW to 3.5 (2.6-5,2) uW. During the follow-up, 44% (n=12) of patients had no PH criteria, 44% (n=12) had residual PH and 11% (n=3) had PH recurrence. There was a reduction of N-terminal pro-B-type natriureticpeptide from 868 (212-1730) pg/mL to 171 (98-382) pg/mL. Rright ventricular systolic function parameters revealed an improvement in longitudinal systolic excursion and peak velocity of the plane of the tricuspid ring from 14 (13-14) mm and 9 (8-10) cm/s to 17 (16-18) mm and 13 (11-15) cm/s, respectively. Of the 26 patients with preoperative right ventricular dysfunction, 85% (n=22) recovered. The proportion of patients on specific vasodilator therapy decreased from 93% to 44% (p<0.001) and the proportion of those requiring oxygen therapy decreased from 52% to 26% (p=0.003). The six-minute walk test distance increased by about 25% compared to the baseline and only eight patients had significant desaturation during the test. Conclusion: Pulmonary endarterectomy performed at an experienced high-volume center is a safe procedure with a very favorable medium-term impact on functional, hemodynamic and right ventricular function parameters in CTEPH patients with operable disease. It is possible for PH centers without PEA differentiation to refer patients safely and effectively to an international surgical center in which air transport is necessary.
- Anticoagulation after typical atrial flutter ablation: systematic review and meta‐analysisPublication . Ferreira, Afonso Nunes; Alves, Mariana; Lima Da Silva, Gustavo; Cortez-Dias, Nuno; De Sousa, João; Pinto, Fausto J.; Caldeira, DanielBackground: Cavotricuspid isthmus (CTI) ablation in typical atrial flutter (AFL) restores sinus rhythm in 95% of patients, which may lead to the discontinuation of oral anticoagulation during follow-up. Therefore, we aimed to systematically review the clinical impact of oral anticoagulation in the incidence of thromboembolic events (TE) after typical AFL ablation. Methods: We searched for controlled studies evaluating the impact of anticoagulation in the incidence of TE in patients submitted to AFL ablation in MEDLINE, CENTRAL, PsycINFO database (June/2021). The primary outcome was TE events (ischemic stroke or systemic embolism). A meta-analysis was performed deriving risk ratios (RR) and 95% confidence intervals (CI). Statistical heterogeneity was measured through I2 metric. The confidence in the evidence was appraised with Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Results: Eight observational studies with 4870 patients were included. TE events were not significantly reduced (RR 1.18, 95% CI 0.59-2.36; n = 4870; GRADE very low). A meta-regression showed that for each 10% increase in the prevalence of previous AF in the studied population, anticoagulation reduced TE risk in 32%. There were no significant differences regarding bleeding events (RR 2.16, 95% CI 0.43-10.97, I2 = 0%; GRADE low), but there was a lower all-cause mortality (RR 0.24, 95% CI 0.17-0.32, GRADE low). Conclusion: The best available evidence lacks robustness and the data did not definitely associate anticoagulation after typical AFL ablation with reduced TE.
- Impact of different activation wavefronts on ischemic myocardial scar electrophysiological properties during high‐density ventricular tachycardia mapping and ablationPublication . Lima Da Silva, Gustavo; Cortez-Dias, Nuno; Ferreira, Afonso Nunes; Nakar, Elad; Francisco, Raquel; Pereira, Mariana; Moreno, Javier; Martins, Raphaël P.; Pinto, Fausto J.; De Sousa, JoãoIntroduction: Scar-related ventricular tachycardia (VT) usually results from an underlying reentrant circuit facilitated by anatomical and functional barriers. The later are sensitive to the direction of ventricular activation wavefronts. We aim to evaluate the impact of different ventricular activation wavefronts on the functional electrophysiological properties of myocardial tissue. Methods: Patients with ischemic heart disease referred for VT ablation underwent high-density mapping using Carto®3 (Biosense Webster). Maps were generated during sinus rhythm, right and left ventricular pacing, and analyzed using a new late potential map software, which allows to assess local conduction velocities and facilitates the delineation of intra-scar conduction corridors (ISCC); and for all stable VTs. Results: In 16 patients, 31 high-resolution substrate maps from different ventricular activation wavefronts and 7 VT activation maps were obtained. Local abnormal ventricular activities (LAVAs) were found in VT isthmus, but also in noncritical areas. The VT isthmus was localized in areas of LAVAs overlapping surface between the different activation wavefronts. The deceleration zone location differed depending on activation wavefronts. Sixty-six percent of ISCCs were similarly identified in all activating wavefronts, but the one acting as VT isthmus was simultaneously identified in all activation wavefronts in all cases. Conclusion: Functional based substrate mapping may improve the specificity to localize the most arrhythmogenic regions within the scar, making the use of different activation wavefronts unnecessary in most cases.
- Long-standing persistent atrial fibrillation : what can we achieve with ablation?Publication . Nunes-Ferreira, Afonso; Cortez-Dias, Nuno; Silverio Antonio, P.; Silva, Gustavo Lima da; Gonçalves, Inês; Aguiar-Ricardo, Inês; Rigueira, Joana; Agostinho, João R.; Santos, R.; Rodrigues, T.; Cunha, N.; Barreiros, C.; Carpinteiro, L.; Pinto, Fausto J.; Sousa, J. deIntroduction: Atrial fibrillation (AF) ablation presents suboptimal results in patients (pts) with persistent long-lasting forms (LSPAF, AF ≥12 months). Recently, the STAR AF-II trial has shown that in these pts complex additional strategies do not improve success compared to only performing pulmonary vein isolation (PVI). Objectives: To evaluate the success of AF ablation, particularly in long-standing persistent AF
- Novel “late potential map” algorithm: abnormal potentials and scar channels detection for ventricular tachycardia ablationPublication . Cortez-Dias, Nuno; Lima Da Silva, Gustavo; Ferreira, Afonso Nunes; Nakar, Elad; Francisco, Raquel; Pereira, Mariana; Carpinteiro, Luís; Pinto, Fausto J.; De Sousa, JoãoBackground: Automated systems for substrate mapping in the context of ventricular tachycardia (VT) ablation may annotate far-field rather than near-field signals, rendering the resulting maps hard to interpret. Additionally, quantitative assessment of local conduction velocity (LCV) remains an unmet need in clinical practice. We evaluate whether a new late potential map (LPM) algorithm can provide an automatic and reliable annotation and localized bipolar voltage measurement of ventricular electrograms (EGMs) and if LCV analysis allows recognizing intrascar conduction corridors acting as VT isthmuses. Methods: In 16 patients referred for scar-related VT ablation, 8 VT activation maps and 29 high-resolution substrate maps from different activation wavefronts were obtained. In offline analysis, the LPM algorithm was compared to manually annotated substrate maps. Locations of the VT isthmuses were compared with the corresponding substrate maps in regard to LCV. Results: The LPM algorithm had an overall/local abnormal ventricular activity (LAVA) annotation accuracy of 94.5%/81.1%, which compares to 83.7%/23.9% for the previous wavefront algorithm. The resultant maps presented a spatial concordance of 88.1% in delineating regions displaying LAVA. LAVA median localized bipolar voltage was 0.22 mV, but voltage amplitude assessment had modest accuracy in distinguishing LAVA from other abnormal EGMs (area under the curve: 0.676; p < .001). LCV analysis in high-density substrate maps identified a median of two intrascar conduction corridors per patient (interquartile range: 2-3), including the one acting as VT isthmus in all cases. Conclusion: The new LPM algorithm and LCV analysis may enhance substrate characterization in scar-related VT.
- Triple-site pacing for cardiac resynchronization in permanent atrial fibrillation : acute phase results from a prospective observational studyPublication . Marques, Pedro; Menezes, Miguel Nobre; Lima da Silva, Gustavo; Bernardes, Ana; Magalhaes, Andreia; Cortez-Dias, Nuno; Carpinteiro, Luis A.; Sousa, João Carvalho de; Pinto, Fausto J.Introduction and Aim: Multi-site pacing is emerging as a new method for improving response to cardiac resynchronization therapy (CRT), but has been little studied, especially in patients with atrial fibrillation. We aimed to assess the effects of triple-site (Tri-V) vs. biventricular (Bi-V) pacing on hemodynamics and QRS duration. Methods: This was a prospective observational study of patients with permanent atrial fibrillation and ejection fraction <40% undergoing CRT implantation (n=40). One right ventricular (RV) lead was implanted in the apex and another in the right ventricular outflow tract (RVOT) septal wall. A left ventricular (LV) lead was implanted in a conventional venous epicardial position. Cardiac output (using the FloTracTM VigileoTM system), mean QRS and ejection fraction were calculated. Results: Mean cardiac output was 4.81±0.97 l/min with Tri-V, 4.68±0.94 l/min with RVOT septal and LV pacing, and 4.68±0.94 l/min with RV apical and LV pacing (p<0.001 for Tri-V vs. both BiV). Mean pre-implantation QRS was 170±25 ms, 123±18 ms with Tri-V, 141±25 ms with RVOT septal pacing and LV pacing and 145±19 with RV apical and LV pacing (p<0.001 for Tri-V vs. both BiV and pre-implantation). Mean ejection fraction was significantly higher with Tri-V (30±11%) vs. Bi-V pacing (28±12% with RVOT septal and LV pacing and 28±11 with RV apical and LV pacing) and pre-implantation (25±8%). Conclusion: Tri-V pacing produced higher cardiac output and shorter QRS duration than Bi-V pacing. This may have a significant impact on the future of CRT.
- First intention epicardial VT ablation : what are the results?Publication . Rodrigues, T. E. Graça; Cortez-Dias, Nuno; Silva, Gustavo Lima da; Agostinho, João R.; Aguiar-Ricardo, Inês; Rigueira, Joana; Nunes-Ferreira, Afonso; Santos, Rui; Cunha, N.; Morais, P.; Pereira, S.; António, Pedro Silvério; Carpinteiro, L.; Pinto, Fausto J.; Sousa, J.Introduction: Ventricular tachycardia (VT) endocardial mapping and ablation may not be sufficient in several arrhythmogenic contexts, because ventricular myocardium may comprise intricate endocardial, intramural and epicardial substract. Thus, epicardial ablation has lately become a complementary and necessary tool to approach some VTs in different types of cardiomyopathies.
- circRNA-miRNA cross-talk in the transition from paroxysmal to permanent atrial fibrillationPublication . Costa, Marina C.; Cortez-Dias, Nuno; Gabriel, André F.; De Sousa, João; Fiuza, Manuela; Gallego, Javier; Nobre, Ângelo; Pinto, Fausto J.; Enguita, Francisco J.Background: Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in western countries. The factors governing the progression of AF to a permanent chronic condition are still not well characterized. Among epigenetic factors, non-coding RNAs (ncRNAs) such as miRNAs and lncRNAs have been recently described as important players involved in the AF progression. We hypothesize about the existence of additional regulatory layers in AF involving an intricate cross-talk between different ncRNA species, namely miRNAs and circRNAs for the establishment of a chronic AF condition. Methods and results: We have performed an unbiased study analyzing the expression profile for miRNAs and circRNAs in left-atrial biopsies from patients with paroxysmal and permanent AF by RNA-seq. The transition from paroxysmal to permanent AF is characterized by a pattern of down-regulated miRNAs, concomitant to the appearance of specific circRNA species. The analysis of the sponging activities of the circRNAs exclusively expressed in permanent AF samples, allowed us to determine that they could be responsible for the downregulation of specific miRNAs in establishment of a permanent AF condition. Conclusion: Sponging activity of circRNAs sequestering specific miRNAs is an important factor to be considered for the determination of the molecular mechanisms involved in AF progression.
- Anticoagulation after typical atrial flutter ablation: systematic review and meta‐analysisPublication . Ferreira, Afonso Nunes; Alves, Mariana; Lima Da Silva, Gustavo; Cortez-Dias, Nuno; De Sousa, João; Pinto, Fausto J.; Caldeira, DanielBackground: Cavotricuspid isthmus (CTI) ablation in typical atrial flutter (AFL) restores sinus rhythm in 95% of patients, which may lead to the discontinuation of oral anticoagulation during follow-up. Therefore, we aimed to systematically review the clinical impact of oral anticoagulation in the incidence of thromboembolic events (TE) after typical AFL ablation. Methods: We searched for controlled studies evaluating the impact of anticoagulation in the incidence of TE in patients submitted to AFL ablation in MEDLINE, CENTRAL, PsycINFO database (June/2021). The primary outcome was TE events (ischemic stroke or systemic embolism). A meta-analysis was performed deriving risk ratios (RR) and 95% confidence intervals (CI). Statistical heterogeneity was measured through I2 metric. The confidence in the evidence was appraised with Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Results: Eight observational studies with 4870 patients were included. TE events were not significantly reduced (RR 1.18, 95% CI 0.59-2.36; n = 4870; GRADE very low). A meta-regression showed that for each 10% increase in the prevalence of previous AF in the studied population, anticoagulation reduced TE risk in 32%. There were no significant differences regarding bleeding events (RR 2.16, 95% CI 0.43-10.97, I2 = 0%; GRADE low), but there was a lower all-cause mortality (RR 0.24, 95% CI 0.17-0.32, GRADE low). Conclusion: The best available evidence lacks robustness and the data did not definitely associate anticoagulation after typical AFL ablation with reduced TE.