ABSTRACT
X-ray absorption near-edge structure (XANES) spectroscopy has been used, in conjunction with extended X-ray absorption fine structure (EXAFS), to determine the coordination structure of the Ag+ ion in a dimethyl sulfoxide (DMSO) solution. From the EXAFS data analysis, the Ag-O first shell distance in DMSO was found to be 2.31(3) Å, with 4.1(5) oxygen atoms surrounding the Ag+ ion, in fair agreement with previous results. This technique did not allow us to determine the geometry of the 4-fold coordination complex and a quantitative analysis of the XANES region was carried out to shed light on this issue. The XANES data analysis confirmed the presence of a four-coordinated complex, unambiguously showing that a regular tetrahedral [Ag(DMSO)4]+ complex is formed when silver triflate is dissolved in DMSO solution.
ABSTRACT
We report a case of successful implantation of a subcutaneous implantable cardioverter-defibrillator in a young patient with severe pectus excavatum presenting with out-of-hospital ventricular fibrillation arrest who was recently surgically repaired with a MIRPE-Nuss procedure. No complications in lead positioning were observed, and the device was tested to determine that it functioned properly.
ABSTRACT
The metal-based deep eutectic solvent (MDES) formed by NiCl2·6H2O and urea in 1:3.5 molar ratio has been prepared for the first time and characterized from a structural point of view. Particular accent has been put on the role of water in the MDES formation, since the eutectic could not be obtained with the anhydrous form of the metal salt. To this end, mixtures at different water/MDES molar ratios (W) have been studied with a combined approach exploiting molecular dynamics and ab initio simulations, UV-vis and near-infra-red spectroscopies, small- and wide-angle X-ray scattering, and X-ray absorption spectroscopy measurements. In the pure MDES, a close packing of Ni2+ ion clusters forming oligomeric agglomerates is present thanks to the mediation of bridging chloride anions and water molecules. Conversely, urea poorly coordinates the metal ion and is mostly found in the interstitial regions among the Ni2+ ion oligomers. This nanostructure is disrupted upon the introduction of additional water, which enlarges the Ni-Ni distances and dilutes the system up to an aqueous solution of the MDES constituents. In the NiCl2·6H2O 1:3.5 MDES, the Ni2+ ion is coordinated on average by one chloride anion and five water molecules, while water easily saturates the metal solvation sphere to provide a hexa-aquo coordination for increasing W values. This multidisciplinary study allowed us to reconstruct the structural arrangement of the MDES and its aqueous mixtures on both short- and intermediate-scale levels, clarifying the fundamental role of water in the eutectic formation and challenging the definition at the base of these complex systems.
ABSTRACT
X-ray absorption spectroscopy (XAS) has been employed to study the coordination of the Ag+ ion in aqueous solution. The conjunction of extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) data analysis provided results suggesting the preference for a first shell linear coordination with a mean Ag-O bond distance of 2.34(2) Å, different from the first generally accepted tetrahedral model with a longer mean Ag-O bond distance. Ab initio molecular dynamics simulations with the Car-Parrinello approach (CPMD) were also performed and were able to describe the coordination of the hydrated Ag+ ion in aqueous solution in very good agreement with the experimental data. The high sensitivity for the closest environment of the photoabsorber of the EXAFS and XANES techniques, together with the long-range information provided by CPMD and large-angle X-ray scattering (LAXS), allowed us to reconstruct the three-dimensional model of the coordination geometry around the Ag+ ion in aqueous solution. The obtained results from experiments and theoretical simulations provided a complex picture with a certain amount of water molecules with high configurational disorder at distances comprised between the first and second hydration spheres. This evidence may have caused the proliferation of the coordination numbers that have been proposed so far for Ag+ in water. Altogether these data show how the description of the hydration of the Ag+ ion in aqueous solution can be complex, differently from other metal species where hydration structures can be described by clusters with well-defined geometries. This diffuse hydration shell causes the Ag-O bond distance in the linear [Ag(H2O)2]+ ion to be ca. 0.2 Å longer than in isolated ions in solid state.
ABSTRACT
Effective and stable contact between the catheter tip and the tissue is crucial for both mapping and lesion formation during cardiac ablation procedures. Contact force catheter may be not only a therapeutic approach to arrhythmias, but also a tool for achieving accurate characterization of the arrhythmic substrate.
ABSTRACT
Early identification of atrial fibrillation (AF) is now a priority in cardiovascular prevention because AF is common although often asymptomatic, and is associated with poor outcomes that are highly preventable with appropriate medical treatment. In Italy, AF prevalence among subjects aged ≥65 years ranges from 5 to 6% in observational studies based on the diagnosis recorded by general practitioners to 10-11% in studies where ECG screening is routinely offered. It is thus evident that a large number of subjects are not detected by conventional approach, and new strategies are required to increase early detection of AF. In particular, the changing position of pharmacies in the health system should be considered. Because of its small geographical size, insular nature and captive population, the Isle of Elba represents an ideal setting to test new strategies for stroke reduction. The Elba-FA project was thus designed to determine the feasibility and impact of the combined involvement of pharmacies and general practices to screen undiagnosed AF, with the ultimate aim of reducing the burden of stroke and arterial thromboembolism. The findings obtained with this approach might have broad implications for cardiovascular prevention at the general population level in Italy.
Subject(s)
Atrial Fibrillation/diagnosis , Atrial Fibrillation/drug therapy , Mass Screening/methods , Pharmacists/standards , Aged , Aged, 80 and over , Atrial Fibrillation/epidemiology , Cross-Sectional Studies , Female , Humans , Italy/epidemiology , Male , Pharmacies/trends , Prevalence , Risk Assessment/methods , Stroke/prevention & controlABSTRACT
BACKGROUND: Chinese people are one of the fastest growing immigrant populations in Europe, and their health has become a key issue to host nations. Although type 2 diabetes (T2DM) is a big burden among migrant populations, data on Chinese immigrants in Europe are limited. METHODS: A cross-sectional survey was performed in 2014, adopting principles of community-based participatory research to investigate T2DM, diagnosed by the American Diabetes Association fasting criteria, in Chinese first-generation migrants aged 16 to 59 years settled in Prato (Italy). Association with different factors was investigated using logistic regression. RESULTS: Of the 1608 participants, 177 had T2DM (11.0%), 119 being newly diagnosed (7.4%). Among subjects with diabetes, 58 (32.8%) were aware of the disease; among subjects with diabetes aware of their condition, 46 (79%) were treated with glucose lowering drugs. Age-standardized (World Health Organization 2001 population) prevalence of T2DM was 9.6% (95% CI 9.1 to 10.2%), being 12.0% (95% CI 11.0 to 12.9%) in men, and 7.8% (95% CI 7.1 to 8.4%) in women. At adjusted logistic regression, diabetes was associated with hypertension, current smoking, adiposity indices (waist circumference, waist-to-hip ratio, waist-to-height ratio, and body mass index), and high triglycerides. T2DM, adiposity indices, and high triglycerides were not associated with duration of stay in Italy. CONCLUSIONS: The high prevalence of T2DM among first-generation Chinese immigrants in Europe stresses the need for specific health programs for T2DM early diagnosis, treatment, and prevention. There is an urgent need for policies to support this group because current policies will produce major social and economic costs. Copyright © 2016 John Wiley & Sons, Ltd.
Subject(s)
Asian People/statistics & numerical data , Diabetes Mellitus, Type 2/epidemiology , Obesity/complications , Transients and Migrants/statistics & numerical data , Adolescent , Adult , Cross-Sectional Studies , Diabetes Mellitus, Type 2/etiology , Female , Follow-Up Studies , Humans , Italy/epidemiology , Male , Middle Aged , Prevalence , Prognosis , Risk Factors , Surveys and Questionnaires , Waist Circumference , Young AdultABSTRACT
INTRODUCTION: Cardiac resynchronization therapy (CRT) device implantation guided by an electroanatomic mapping system (EAMS) is an emerging technique that may reduce fluoroscopy and angiography use and provide information on coronary sinus (CS) electrical activation. We evaluated the outcome of the EAMS-guided CRT implantation technique in a multicenter registry. METHODS: During the period 2011-2014 we enrolled 125 patients (80% males, age 74 [71-77] years) who underwent CRT implantation by using the EnSite system to create geometric models of the patient's cardiac chambers, build activation mapping of the CS, and guide leads positioning. Two hundred and fifty patients undergoing traditional CRT implantation served as controls. Success and complication rates, fluoroscopy and total procedure times in the overall study population and according to center experience were collected. Centers that performed ≥10 were defined as highly experienced. RESULTS: Left ventricular lead implantation was successful in 122 (98%) cases and 242 (97%) controls (P = 0.76). Median fluoroscopy time was 4.1 (0.3-10.4) minutes in cases versus 16 (11-26) minutes in controls (P < 0.001). Coronary sinus angiography was performed in 33 (26%) cases and 208 (83%) controls (P < 0.001). Complications occurred in 5 (4%) cases and 17 (7%) controls (P = 0.28). Median fluoroscopy time (median 11 minutes vs. 3 minutes, P < 0.001) and CS angiography rate (55% vs. 21%, P < 0.001) were significantly higher in low experienced centers, while success rate and complications rate were similar. CONCLUSIONS: EAMS-guided CRT implantation proved safe and effective in both high- and low-experienced centers and allowed to reduce fluoroscopy use by ≈75% and angiography rate by ≈70%.
Subject(s)
Arrhythmias, Cardiac/therapy , Cardiac Resynchronization Therapy Devices , Cardiac Resynchronization Therapy , Electrophysiologic Techniques, Cardiac , Heart Failure/therapy , Imaging, Three-Dimensional , Therapy, Computer-Assisted/instrumentation , Action Potentials , Aged , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/physiopathology , Case-Control Studies , Coronary Angiography , Feasibility Studies , Female , Fluoroscopy , Heart Failure/diagnosis , Heart Failure/physiopathology , Heart Rate , Humans , Image Interpretation, Computer-Assisted , Italy , Male , Patient-Specific Modeling , Predictive Value of Tests , Radiography, Interventional , Registries , Signal Processing, Computer-Assisted , Time Factors , Treatment Outcome , Ventricular Function, LeftABSTRACT
BACKGROUND: Despite the public health burden of atrial fibrillation (AF) and its complications in China, there is no literature on AF among Chinese living in Europe. The present study was performed to investigate the prevalence of and risk factors for AF in Chinese first generation migrants settled in Europe. METHODS: A cross-sectional survey was performed in 2014 on Chinese first generation migrants aged 16 to 59years settled in Prato (Italy) adopting principles of community based participatory research. All participants underwent recording of 30s of a single-channel ECG and associations of AF with socio-demographic, anthropometric, clinical factors, and sleep history were examined using logistic regression. RESULTS: Of the 1608 participants, 12 had AF (0.75%; 95% CI 0.33 to 1.17) - four men and eight women. All subjects with AF had a CHA2DS2VASc index≥1. Although no participant with AF had contraindications to oral anticoagulation, none was treated with oral anticoagulants. At multivariable adjusted logistic regression AF was associated with hypertension with an OR of 4.40 (95% CI 1.09-17.81; p=0.038). CONCLUSIONS: Chinese are one of the fastest growing migrant populations in Europe and their health has become a key issue to host nations. The issue of AF is to be considered in future prevention programs for elusive ethnic minorities and adequately powered trials specifically designed to investigate AF prevalence and to test prevention approaches are now needed.
Subject(s)
Asian People/statistics & numerical data , Atrial Fibrillation/epidemiology , Hypertension/epidemiology , Adolescent , Adult , Atrial Fibrillation/ethnology , China/ethnology , Community-Based Participatory Research , Cross-Sectional Studies , Female , Health Surveys , Humans , Italy/epidemiology , Logistic Models , Male , Middle Aged , Prevalence , Risk Factors , Transients and Migrants , Young AdultABSTRACT
BACKGROUND: Fluoroscopic guidance is the standard tool used in device implantation. This means that both the patient and the operator are exposed to radiation, which may sometimes be high. The possibility of single-lead permanent pacemaker implantation without fluoroscopy has already been demonstrated. OBJECTIVE: The aim of our study was to investigate the feasibility and reliability of biventricular device implantation guided only by an electroanatomic navigation system. METHODS: Sixty-one patients with heart failure underwent implantation of a cardiac resynchronization therapy (CRT) device with or without defibrillator (CRT-D; CRT-P). The procedure was performed with or without fluoroscopy guidance (Rx+; Rx0). In the latter case, the EnSite Velocity system was used; this system is able to reconstruct the anatomy and activation of the cardiac chambers by simultaneously collecting a "cloud" of anatomical points from multiple electrodes. RESULTS: Lead positioning was achieved in 24 of 26 patients undergoing CRT implantation without fluoroscopy (92% success). No complications were observed during the procedure and no catheter dislodgment occurred the day after the implantation or during 1-month follow-up. Procedure time progressively decreased from 136 minutes in the first case to 59 minutes in the last one, suggesting that operators gradually gained confidence while using the new technique. CONCLUSION: Our study demonstrates the feasibility, efficacy, and safety of lead positioning guided only by the nonfluoroscopic EnSite Velocity mapping system without the use of fluoroscopy in CRT-P or CRT-D implantation. The benefits in terms of significantly reduced fluoroscopy exposure are associated with technical and clinical advantages.
Subject(s)
Body Surface Potential Mapping/methods , Cardiac Resynchronization Therapy/methods , Fluoroscopy , Heart Failure/surgery , Prosthesis Implantation/methods , Radiation Exposure/prevention & control , Aged , Cardiac Resynchronization Therapy Devices , Feasibility Studies , Female , Fluoroscopy/adverse effects , Fluoroscopy/methods , Humans , Italy , Male , Middle Aged , Prosthesis Fitting/methods , Reproducibility of Results , Surgery, Computer-Assisted/adverse effects , Surgery, Computer-Assisted/methods , Treatment OutcomeABSTRACT
BACKGROUND: Radiation exposure related to conventional tachyarrhythmia radiofrequency catheter ablation (RFCA) carries small but not negligible stochastic and deterministic effects on health. These effects are cumulative and potentially more harmful in younger individuals. Nonfluoroscopic mapping systems can significantly reduce the radiological exposure and in some cases it can completely eliminate it. OBJECTIVE: The aim of this study was to assess the safety, feasibility, and efficacy of a complete nonfluoroscopic approach for RFCA compared with ablation procedures performed under fluoroscopic guidance. METHODS: RFCA was performed in 442 consecutive patients (mean age 58 ± 19 years). The first 145 patients (group 1) were treated only under fluoroscopic guidance, and the following 297 patients (group 2) were treated using a nonfluoroscopic electroanatomic mapping system (EnSite Velocity). RFCA was completely performed without fluoroscopy in 255 of 297 patients in group 2 (86%). RESULTS: The acute success rate did not differ between group 1 and group 2 (97% vs 96%; P = .46), and there were no differences in either procedure time (87 ± 57 minutes vs 91 ± 52 minutes; P = .41) or complication rate. Fluoroscopic exposure in group 2 was significantly reduced in comparison with group 1 (14 ± 6 seconds vs 1159 ± 833 seconds; P < .0001). CONCLUSION: Compared with the conventional fluoroscopic technique, the near-zero radiation (RX) approach provides similar outcomes and may significantly reduce or eliminate ionizing radiation exposure in RFCA. These reductions are achieved without altering the duration or compromising the safety and effectiveness of the procedure.
Subject(s)
Body Surface Potential Mapping/methods , Catheter Ablation/methods , Fluoroscopy/methods , Radiation Monitoring/methods , Tachycardia/surgery , Adult , Aged , Female , Humans , Male , Middle Aged , Monitoring, Intraoperative/methods , Operative Time , Radiologic Health/methods , Retrospective Studies , Tachycardia/diagnosis , Tachycardia/physiopathology , Time Factors , Treatment OutcomeSubject(s)
Atrial Flutter/diagnosis , Atrial Flutter/physiopathology , Myotonic Dystrophy/diagnosis , Myotonic Dystrophy/physiopathology , Atrial Flutter/pathology , Echocardiography, Three-Dimensional/methods , Electrocardiography/methods , Heart Atria/diagnostic imaging , Heart Atria/pathology , Humans , Middle Aged , Myotonic Dystrophy/pathology , RecurrenceABSTRACT
AIMS: Despite its proven efficacy, the Cox-Maze III procedure did not gain widespread acceptance for the treatment of stand-alone atrial fibrillation (SA-AF) because of its complexity and technical difficulty. Surgical ablation for SA-AF can now be successfully performed utilizing minimally invasive surgery (MIS). This study provides an overview of state-of-the-art MIS for the treatment of SA-AF. METHODS AND RESULTS: Studies selected for this review were identified on PUBMED and exclusion and inclusion criteria were applied to select the publication to be screened. Twenty-eight studies were included; 27 (96.4%) were observational in nature whereas 1 was prospective non-randomized. The total number of patients was 1051 (range 14-114). Mean age ranged from 45.3 to 67.1 years. Suboptimal results were obtained when employing microwave and high focused ultrasound energies. In contrast, MIS ablation of SA-AF achieved satisfactory 1-year results when the bipolar radiofrequency was employed as energy source, with antiarrhythmic drug-free success rate comparable to percutaneous catheter ablation (PCA). The success rate in paroxysmal was even higher than in PCA. In contrast, ganglionated plexi ablation and left atrial appendage removal seem not to influence the recurrence of AF and the occurrence of postoperative thromboembolic events. CONCLUSION: Minimally invasive surgery ablation of SA-AF achieved satisfactory 1-year results when the bipolar radiofrequency was employed. Nevertheless, the relatively high complication rate reported suggest that such techniques require further refinement. Finally, the preliminary results of the hybrid approach are promising but they need to be confirmed.
Subject(s)
Atrial Fibrillation/surgery , Catheter Ablation , Minimally Invasive Surgical Procedures , HumansABSTRACT
BACKGROUND: We compared short-term results of a hybrid versus a standard surgical bilateral thoracoscopic approach employing radiofrequency (RF) sources in the surgical treatment of lone atrial fibrillation (LAF). METHODS: Between January 2008 and July 2010 sixty-three consecutive patients with LAF underwent minimally invasive surgery. Thirty-five (55.5%) underwent surgery with the hybrid approach whereas 28 (45.5%) underwent bilateral thoracoscopic standard procedure (no-hybrid group). All patients underwent continuous 7-day Holter Monitoring (HM) at 3 months, 6 months and 1 year. RESULTS: At 1 year, 91.4% and 82.1% (time-related prevalence 5.2% vs.6.0% [p=0.56]) of the patients were free of AF and AAD. The hybrid group yielded better results in long standing persistent AF (8.2% [time related prevalence 81.8% vs. 44.4%, p=0.001] vs.14.9%, p=0.04). One-year success rates were 87.5% vs. 100% (p=0.04) in persistent [time related prevalence 3.8% vs. 0%, p<0.001] and 87.5% vs. 100% (p=0.04) in paroxysmal AF [time related prevalence 3.2% vs. 0%, p<0.001] in the two groups. One-year prevalence of Warfarin use was significantly higher in the hybrid group (29.0% [26.2-33.1] and 13.4% [9.9-16.3]) with no difference by AF type. LA reverse remodeling occurred in 81.7% (n=30) of hybrid patients and 67.8% (n=19) of no-hybrid patients at latest control (p=0.02). Left atrial emptying fraction increased in both groups (50 ± 14%, p<0.001 and 52 ± 12%, p=0.004 in hybrid and no-hybrid, respectively) without differences between groups (p=0.6). CONCLUSIONS: The hybrid procedure yielded excellent results in long-standing persistent AF. Our findings need to be confirmed by further larger studies.
Subject(s)
Atrial Fibrillation/diagnostic imaging , Atrial Fibrillation/surgery , Catheter Ablation/methods , Minimally Invasive Surgical Procedures/methods , Aged , Catheter Ablation/standards , Echocardiography, Doppler, Pulsed/methods , Female , Follow-Up Studies , Humans , Male , Middle Aged , Minimally Invasive Surgical Procedures/standards , Practice Guidelines as Topic/standards , Treatment OutcomeABSTRACT
Situs viscerum inversus totalis (SVIT) is a congenital disorder characterized by mirror reversal of the thoracic and abdominal organs. Different studies have shown that the ablation procedure can be performed without fluoroscopy with safety and effectiveness, in the setting of supraventricular tachycardia. We successfully performed an anatomical map and a radiofrequency catheter ablation of ventricular arrhythmia in a patient with SVIT without fluoroscopy.
Subject(s)
Catheter Ablation/methods , Situs Inversus/surgery , Tachycardia, Ventricular/surgery , Electrocardiography , Fluoroscopy , Humans , Male , Middle Aged , Situs Inversus/diagnostic imaging , Tachycardia, Ventricular/diagnostic imaging , Treatment OutcomeABSTRACT
OBJECTIVE: Postoperative atrial fibrillation (AF) is a frequent complication after cardiac surgery. AF may also occur after hospital discharge during postacute rehabilitation. Several studies have addressed the AF that occurs in the hospital after surgery, and predictors have already been identified. Postoperative AF that occurs after hospital discharge has not been investigated thoroughly, and predictors are still unknown. In this study, we hypothesized that moderate-intensity physical activity in the year before surgery might favorably affect the incidence of AF during postacute rehabilitation. DESIGN: We tested our hypothesis in a cohort of 158 older patients admitted to a medical rehabilitation facility for postacute inpatient rehabilitation after coronary surgery and continuously monitored by telemetry for the duration of the rehabilitation. RESULTS: Independent of potential confounders, patients who reported low-intensity physical activity in the year before surgery showed a significantly higher incidence of AF during postacute rehabilitation when compared with those who reported moderate-intensity physical activity (32.1% vs. 8.1%; P = 0.029). Other independent predictors of AF during postacute rehabilitation were the occurrence of AF during the patients' stay in hospital, larger left atrial volume, and lower left atrial emptying fraction. CONCLUSIONS: These findings confirm our hypothesis that physical activity in the year before surgery affects the incidence of postoperative AF during postacute rehabilitation. The results also provide information regarding possible predictors that may assist in identifying patients who could benefit from preventive treatments.
Subject(s)
Atrial Fibrillation/epidemiology , Coronary Artery Bypass/rehabilitation , Motor Activity , Postoperative Complications , Rehabilitation Centers , Aged , Aged, 80 and over , Cardiovascular Diseases/complications , Cardiovascular Diseases/physiopathology , Cardiovascular Diseases/therapy , Cohort Studies , Exercise , Female , Humans , Incidence , Life Style , Male , Risk Factors , TelemetryABSTRACT
Isolated ventricular premature beats are the most common arrhythmia in clinical practice. Not all ventricular premature beats are equal, as they may evolve into worsening of the arrhythmia and even severe left ventricular dysfunction in some subsets of patients, particularly those with frequent ventricular premature beats originating from the left ventricle. The resulting systolic dysfunction is reversible following arrhythmia termination. Radiofrequency ablation allows us to achieve effective and safe results and should be considered the treatment of choice. We report a case of left ventricular dysfunction without signs of structural heart disease, secondary to left ventricular premature beats evolved into runs of non-sustained ventricular tachycardia, successfully treated with radiofrequency ablation of the arrhythmic focus.
Subject(s)
Ventricular Dysfunction, Left/etiology , Ventricular Premature Complexes/complications , Ventricular Premature Complexes/surgery , Adolescent , Catheter Ablation/methods , Humans , MaleABSTRACT
PURPOSE: We hypothesized that inducibility of the VT responsible for ICD therapies at the end of RFCA, would also be associated with a differential risk, depending on left ventricular function. METHODS: We retrospectively studied 66 patients with previous myocardial infarction and with ICD who also underwent RFCA for recurrent refractory VTs. RESULTS: During the follow-up only 19 patients (29%) showed VTs. Among patients with ejection fraction (EF)
Subject(s)
Catheter Ablation/adverse effects , Coronary Artery Disease/complications , Coronary Artery Disease/surgery , Defibrillators, Implantable , Tachycardia, Ventricular/etiology , Tachycardia, Ventricular/prevention & control , Female , Humans , Male , Middle Aged , Tachycardia, Ventricular/diagnosis , Treatment OutcomeABSTRACT
Simultaneous stimulation of 2 left ventricular (LV) sites could enhance the effectiveness of cardiac resynchronization therapy (CRT). The aim of this study was to evaluate the acute hemodynamic response to dual-site LV CRT. Two LV pacing leads were successfully implanted in 12 CRT candidates (New York Heart Association classes III to IV, QRS >or=120 ms). Target positions were the lateral or posterolateral vein (site A) and anterior or anterolateral vein (site B). A conductance catheter was placed in the left ventricle for pressure-volume measurements. Tested CRT configurations were alternated by atrial overdrive pacing at a fixed rate and included site A and B single-site CRT and dual-site LV CRT (2 LV sites plus right ventricular apex) at 4 atrioventricular intervals. Overall, single-site LV CRT significantly enhanced stroke volume, stroke work, maximum pressure derivative, and conductance-derived indexes of LV synchrony when delivered in site A, whereas no significant changes were noticed with pacing in site B. Specifically, site-A pacing resulted in a higher stroke volume increase (LV pacing site associated with the best hemodynamic response [best-LV]) in 8 patients, and site-B pacing, in 4 patients. At intermediate atrioventricular intervals, dual-site LV CRT resulted in improved stroke volume, stroke work, maximum pressure derivative, and LV synchrony with respect to single-site CRT when delivered at the best-LV (all p <0.05). However, single-site CRT at best-LV produced results similar to dual-site LV CRT when the atrioventricular interval was optimized in each patient. In conclusion, adding a second LV lead does not result in further improvement in acute hemodynamic response with respect to standard CRT when the single LV pacing site and atrioventricular interval are optimal.
Subject(s)
Cardiac Pacing, Artificial/methods , Heart Failure/therapy , Hemodynamics , Adult , Aged , Aged, 80 and over , Female , Heart Failure/physiopathology , Heart Rate , Humans , Male , Middle Aged , Pacemaker, Artificial , Stroke Volume , Ventricular PressureABSTRACT
BACKGROUND: Whether cooling catheters should be preferred for atrial fibrillation (AF) ablation is not yet clear. METHODS: From April 2005 to October 2006, 991 (74% men) consecutive patients who underwent AF ablation were prospectively enrolled in 10 Italian centers. For the present subanalysis, patients were ranked in the two study groups on the basis of the catheter system chosen: 8-mm tip was used in 86 patients (9% conventional group) and open-irrigated tip in 905 patients (91% cooled group). RESULTS: The registry clinical data of both groups showed marked heterogeneity due to the fact that the higher number of patients of the cooled group had longer AF history (4.9+/-4.1 versus 1.2+/-1.8 years; P=0.0001), permanent/persistent AF (41.2 versus 27.9%; P=0.01), and larger left atrium (LA) size (44.1+/-6.2 versus 33.4+/-10.5 mm; PSubject(s)
Atrial Fibrillation/surgery
, Catheter Ablation/instrumentation
, Catheter Ablation/adverse effects
, Catheter Ablation/methods
, Female
, Humans
, Male
, Middle Aged