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2.
Artigo em Inglês | MEDLINE | ID: mdl-31934784

RESUMO

Background - ECG Imaging (ECGI) has been used to guide treatment of ventricular ectopy and arrhythmias. However, the accuracy of ECGI in localizing the origin of arrhythmias during catheter ablation of ventricular tachycardia (VT) in structurally abnormal hearts remains to be fully validated. Methods - During catheter ablation of VT, simultaneous mapping was performed using electro-anatomical mapping (EAM) (CARTO, Biosense-Webster) and ECGI (CardioInsight™, Medtronic) in 18 patients. Sites of entrainment, pace-mapping and termination during ablation were used to define the VT site of origin (SoO). Distance between SoO and the site of earliest activation on ECGI were measured using co-registered geometries from both systems. The accuracy of ECGI vs a 12-lead surface ECG algorithm was compared. Results - A total of 29 VTs were available for comparison. Distance between SoO and sites of earliest activation in ECGI was 22.6, 13.9-36.2 mm (median, first-third quartile). ECGI mapped VT sites of origin onto the correct AHA segment with higher accuracy than a validated 12-lead ECG algorithm (83.3% vs 38.9%, P=0.015). Conclusions - This simultaneous assessment demonstrates that CardioInsight™ localizes VT circuits with sufficient accuracy to provide a region of interest for targeting mapping for ablation. Resolution is not sufficient to guide discrete radiofrequency lesion delivery via catheter ablation without concomitant use of an electro-anatomical mapping system, but may be sufficient for segmental ablation with radiotherapy.

4.
Curr Med Chem ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31838987

RESUMO

Atrial fibrillation (AF) is a growing public health issue, associated with significant morbidity and mortality. In addition to pharmacological therapy, catheter ablation is an effective strategy in restoring and maintaining sinus rhythm. However, ablation is not without risk, and AF recurs in a significant proportion of patients. Non-invasive, easily accessible markers or indices that could stratify patients depending on the likelihood of a successful outcome following ablation would allow us to select the most appropriate patients for the procedure, reducing the AF recurrence rate and exposure to potentially life-threatening risks. There has been much attention paid to brain natriuretic peptide (BNP) and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) as possible predictive markers of successful ablation. Several studies have demonstrated an association between higher pre-ablation levels of these peptides, and a greater likelihood of AF recurrence. Therefore, there may be a role for measuring brain natriuretic peptides levels when selecting patients for catheter ablation.

5.
Heart Rhythm ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31751771

RESUMO

BACKGROUND: Identifying arrhythmogenic sites to improve ventricular tachycardia (VT) ablation outcomes remains unresolved. The re-entry vulnerability index (RVI) combines activation and repolarization timings to identify sites critical for re-entrant arrhythmia initiation without inducing VT. OBJECTIVE: To provide the first assessment of RVI's capability to identify VT sites of origin using high-density contact mapping and comparison with other activation-repolarization markers of functional substrate. METHODS: 18 VT ablation patients (16M, 72% ischemic) were studied. Unipolar electrograms were recorded during ventricular pacing and analysed off-line. Activation time (AT), activation-recovery interval (ARI), repolarization time (RT) were measured. Vulnerability to re-entry was mapped based on RVI and spatial distribution of AT, ARI and RT. The distance from sites identified as vulnerable to re-entry to the VT site of origin was measured, with distances <10 mm and >20 mm indicating accurate and inaccurate localization, respectively. RESULTS: The origin of 18 VTs was identified (n=6 entrainment, n=12 pace-mapping). RVI maps included 1012, 408-2098 (median, 1st-3rd quartiles) points/patient. RVI accurately localized 72.2% VT sites of origin, with median distance equal to 5.1, 3.2-10.1 mm. Inaccurate localization was significantly less frequent for RVI than AT (5.6% vs 33.3%, OR=0.12, P=0.035). Compared to RVI, distance to VT sites of origin was significantly larger for sites showing prolonged RT and ARI, and non-significantly larger for sites showing highest AT and ARI gradients. CONCLUSION: RVI identifies vulnerable regions closest to VT sites of origin. Activation-repolarization metrics may improve VT substrate delineation and inform novel ablation strategies.

8.
Pacing Clin Electrophysiol ; 42(12): 1541-1551, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31677279

RESUMO

BACKGROUND: Use of the subcutaneous implantable defibrillator (S-ICD) has increased because the device received US Food and Drug Administration approval in 2012, but we still know little about whether the quality of life (QoL) of patients with an S-ICD versus a transvenous ICD (TV-ICD) is comparable. We compared S-ICD patients with TV-ICD patients on QoL, depression, and anxiety up to 12 months' follow-up. METHODS: A matched cohort of S-ICD (N = 167) and TV-ICD patients (N = 167) completed measures on QoL, depression, anxiety, and personality at baseline, 3, 6, and 12 months post implant. Data were analyzed using multivariable modeling with repeated measures. RESULTS: In adjusted analyses, we found no statistically significant differences between cohorts on physical and mental QoL and depression (all Ps > .05), while S-ICD patients reported lower anxiety than TV-ICD patients (P = 0.0007). Both cohorts experienced improvements in physical and mental QoL and symptoms of depression and anxiety over time (all Ps < .001), primarily between implant and 3 months. These improvements were similar for both cohorts with respect to physical and mental QoL and anxiety (Ps > .05), while S-ICD patients experienced greater reductions in depressive symptoms (P = .0317). CONCLUSION: The QoL and depression levels were similar in patients with an S-ICD and a TV-ICD up to 12 months' follow-up, while S-ICD patients reported lower anxiety levels and a greater reduction in depression over time as compared to TV-ICD patients. This knowledge may be important for patients and clinicians, if the indication for implantation allows both the S-ICD and the TV-ICD, making a choice possible.

9.
J Am Heart Assoc ; 8(20): e012253, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31581876

RESUMO

Background Outcomes of catheter ablation of atrial fibrillation (AF) are variable and the predictors of success require further elucidation since the identification of correctable risk factors could help to optimize therapy. We aimed to assess the impact of body mass index (BMI) in the overall safety and efficacy of catheter ablation of AF, with emphasis on the use of cryoballoon ablation and novel oral anticoagulants. Methods and Results There were 2497 consecutive patients undergoing catheter ablation of AF in 7 European high volume centers were stratified according to BMI (normal weight <25 kg/m2, pre-obese 25-30 kg/m2, obesity 30-35 kg/m2, and morbid obesity ≥35 kg/m2) and comparisons of procedural outcomes evaluated. Pre-obese and obese patients presented more comorbidities (hypertension, diabetes mellitus, and sleep apnea), and had higher rates of non-paroxysmal AF ablation procedures. The rate of atrial 12-month arrhythmia relapse increased alongside with BMI (35.2%, 35.7%, 43.6%, and 48.0% P<0.001). During a median follow-up of 18.8 months (interquartile range 11-28), after adjusting for all baseline differences, BMI was an independent predictor of relapse (hazard ratio=1.01 per kg/m2; 95% CI 1.01-1.02; P=0.002), adding incremental predictive value to obstructive sleep apnea. BMI was not a predictor for any of the reported complications. Using novel oral anticoagulants and cryoballoon ablation was safe and efficacy was comparable with vitamin-K antagonists and radiofrequency ablation. Conclusions Obese patients present with a more adverse comorbidity profile, more advanced forms of AF, and have lower chances of being free from AF relapse after ablation. Use of novel oral anticoagulants and cryoballoon ablation may be an option in this patient group.

10.
J Cardiovasc Electrophysiol ; 30(12): 2900-2906, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31578806

RESUMO

INTRODUCTION: Implantable loop recorders (ILR) are predominantly implanted by cardiologists in the catheter laboratory. We developed a nurse-delivered service for the implantation of LINQ (Medtronic; Minnesota) ILRs in the outpatient setting. This study compared the safety and cost-effectiveness of the introduction of this nurse-delivered ILR service with contemporaneous physician-led procedures. METHODS: Consecutive patients undergoing an ILR at our institution between 1st July 2016 and 4th June 2018 were included. Data were prospectively entered into a computerized database, which was retrospectively analyzed. RESULTS: A total of 475 patients underwent ILR implantation, 271 (57%) of these were implanted by physicians in the catheter laboratory and 204 (43%) by nurses in the outpatient setting. Six complications occurred in physician-implants and two in nurse-implants (P = .3). Procedural time for physician-implants (13.4 ± 8.0 minutes) and nurse-implants (14.2 ± 10.1 minutes) were comparable (P = .98). The procedural cost was estimated as £576.02 for physician-implants against £279.95 with nurse-implants, equating to a 57.3% cost reduction. In our center, the total cost of ILR implantation in the catheter laboratory by physicians was £10 513.13 p.a. vs £6661.55 p.a. with a nurse-delivered model. When overheads for running, cleaning, and maintaining were accounted for, we estimated a saving of £68 685.75 was performed by moving to a nurse-delivered model for ILR implants. Over 133 catheter laboratory and implanting physician hours were saved and utilized for other more complex procedures. CONCLUSION: ILR implantation in the outpatient setting by suitably trained nurses is safe and leads to significant financial savings.

11.
Circ Arrhythm Electrophysiol ; 12(10): e007549, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31607149

RESUMO

BACKGROUND: Early prediction of cardiovascular risk in the general population remains an important issue. The T-wave morphology restitution (TMR), an ECG marker quantifying ventricular repolarization dynamics, is strongly associated with cardiovascular mortality in patients with heart failure. Our aim was to evaluate the cardiovascular prognostic value of TMR in a UK middle-aged population and identify any genetic contribution. METHODS: We analyzed ECG recordings from 55 222 individuals from a UK middle-aged population undergoing an exercise stress test in UK Biobank (UKB). TMR was used to measure ventricular repolarization dynamics, exposed in this cohort by exercise (TMR during exercise, TMRex) and recovery from exercise (TMR during recovery, TMRrec). The primary end point was cardiovascular events; secondary end points were all-cause mortality, ventricular arrhythmias, and atrial fibrillation with median follow-up of 7 years. Genome-wide association studies for TMRex and TMRrec were performed, and genetic risk scores were derived and tested for association in independent samples from the full UKB cohort (N=360 631). RESULTS: A total of 1743 (3.2%) individuals in UKB who underwent the exercise stress test had a cardiovascular event, and TMRrec was significantly associated with cardiovascular events (hazard ratio, 1.11; P=5×10-7), independent of clinical variables and other ECG markers. TMRrec was also associated with all-cause mortality (hazard ratio, 1.10) and ventricular arrhythmias (hazard ratio, 1.16). We identified 12 genetic loci in total for TMRex and TMRrec, of which 9 are associated with another ECG marker. Individuals in the top 20% of the TMRrec genetic risk score were significantly more likely to have a cardiovascular event in the full UKB cohort (18 997, 5.3%) than individuals in the bottom 20% (hazard ratio, 1.07; P=6×10-3). CONCLUSIONS: TMR and TMR genetic risk scores are significantly associated with cardiovascular risk in a UK middle-aged population, supporting the hypothesis that increased spatio-temporal heterogeneity of ventricular repolarization is a substrate for cardiovascular risk and the validity of TMR as a cardiovascular risk predictor.

12.
J Am Heart Assoc ; 8(18): e012097, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31496332

RESUMO

Background The relationship between structural pathology and electrophysiological substrate in cardiac amyloidosis is unclear. Differences between light-chain (AL) and transthyretin (ATTR) cardiac amyloidosis may have prognostic implications. Methods and Results ECG imaging and cardiac magnetic resonance studies were conducted in 21 cardiac amyloidosis patients (11 AL and 10 ATTR). Healthy volunteers were included as controls. With respect to ATTR, AL patients had lower amyloid volume (51.0/37.7 versus 73.7/16.4 mL, P=0.04), lower myocardial cell volume (42.6/19.1 versus 58.5/17.2 mL, P=0.021), and higher T1 (1172/64 versus 1109/80 ms, P=0.022) and T2 (53.4/2.9 versus 50.0/3.1 ms, P=0.003). ECG imaging revealed differences between cardiac amyloidosis and control patients in virtually all conduction-repolarization parameters. With respect to ATTR, AL patients had lower epicardial signal amplitude (1.07/0.46 versus 1.83/1.26 mV, P=0.026), greater epicardial signal fractionation (P=0.019), and slightly higher dispersion of repolarization (187.6/65 versus 158.3/40 ms, P=0.062). No significant difference between AL and ATTR patients was found using the standard 12-lead ECG. T1 correlated with epicardial signal amplitude (cc=-0.78), and extracellular volume with epicardial signal fractionation (cc=0.48) and repolarization time (cc=0.43). Univariate models based on single features from both cardiac magnetic resonance and ECG imaging classified AL and ATTR patients with an accuracy of 70% to 80%. Conclusions In this exploratory study cardiac amyloidosis was associated with ventricular conduction and repolarization abnormalities, which were more pronounced in AL than in ATTR. Combined ECG imaging-cardiac magnetic resonance analysis supports the hypothesis that additional mechanisms beyond infiltration may contribute to myocardial damage in AL amyloidosis. Further studies are needed to assess the clinical impact of this approach.

14.
Europace ; 21(11): 1670-1677, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504477

RESUMO

AIMS : To define the clinical characteristics and long-term clinical outcomes of a large cohort of patients with idiopathic ventricular fibrillation (IVF) and normal 12-lead electrocardiograms (ECGs). METHODS AND RESULTS: Patients with ventricular fibrillation as the presenting rhythm, normal baseline, and follow-up ECGs with no signs of cardiac channelopathy including early repolarization or atrioventricular conduction abnormalities, and without structural heart disease were included in a registry. A total of 245 patients (median age: 38 years; males 59%) were recruited from 25 centres. An implantable cardioverter-defibrillator (ICD) was implanted in 226 patients (92%), while 18 patients (8%) were treated with drug therapy only. Over a median follow-up of 63 months (interquartile range: 25-110 months), 12 patients died (5%); in four of them (1.6%) the lethal event was of cardiac origin. Patients treated with antiarrhythmic drugs only had a higher rate of cardiovascular death compared to patients who received an ICD (16% vs. 0.4%, P = 0.001). Fifty-two patients (21%) experienced an arrhythmic recurrence. Age ≤16 years at the time of the first ventricular arrhythmia was the only predictor of arrhythmic recurrence on multivariable analysis [hazard ratio (HR) 0.41, 95% confidence interval (CI) 0.18-0.92; P = 0.03]. CONCLUSION : Patients with IVF and persistently normal ECGs frequently have arrhythmic recurrences, but a good prognosis when treated with an ICD. Children are a category of IVF patients at higher risk of arrhythmic recurrences.

15.
Sci Rep ; 9(1): 13016, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506584

RESUMO

Almost a third of patients fulfilling current guidelines criteria have suboptimal responses following cardiac resynchronization therapy (CRT). Circulating biomarkers may help identify these patients. We aimed to assess the predictive role of full blood count (FBC) parameters in prognosis of heart failure (HF) patients undergoing CRT device implantation. We enrolled 612 consecutive CRT patients and FBC was measured within 24 hours prior to implantation. The follow-up period was a median of 1652 days (IQR: 837-2612). The study endpoints were i) composite of all-cause mortality or transplant, and ii) reverse left ventricular (LV) remodeling. On multivariate analysis [hazard ratio (HR), 95% confidence interval (CI)] only red cell count (RCC) (p = 0.004), red cell distribution width (RDW) (p < 0.001), percentage of lymphocytes (p = 0.03) and platelet count (p < 0.001) predicted all-cause mortality. Interestingly, RDW (p = 0.004) and platelet count (p = 0.008) were independent predictors of reverse LV remodeling. This is the first powered single-centre study to demonstrate that RDW and platelet count are independent predictors of long-term all-cause mortality and/or heart transplant in CRT patients. Further studies, on the role of these parameters in enhancing patient selection for CRT implantation should be conducted to confirm our findings.

16.
Europace ; 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31408153

RESUMO

AIMS: To evaluate population-based electronic health record (EHR) definitions of atrial fibrillation (AF) and valvular heart disease (VHD) subtypes, time trends in prevalence and prognosis. METHODS AND RESULTS: A total of 76 019 individuals with AF were identified in England in 1998-2010 in the CALIBER resource, linking primary and secondary care EHR. An algorithm was created, implemented, and refined to identify 18 VHD subtypes using 406 diagnosis, procedure, and prescription codes. Cox models were used to investigate associations with a composite endpoint of incident stroke (ischaemic, haemorrhagic, and unspecified), systemic embolism (SSE), and all-cause mortality. Among individuals with AF, the prevalence of AF with concomitant VHD increased from 11.4% (527/4613) in 1998 to 17.6% (7014/39 868) in 2010 and also in individuals aged over 65 years. Those with mechanical valves, mitral stenosis (MS), or aortic stenosis had highest risk of clinical events compared to AF patients with no VHD, in relative [hazard ratio (95% confidence interval): 1.13 (1.02-1.24), 1.20 (1.05-1.36), and 1.27 (1.19-1.37), respectively] and absolute (excess risk: 2.04, 4.20, and 6.37 per 100 person-years, respectively) terms. Of the 95.2% of individuals with indication for warfarin (men and women with CHA2DS2-VASc ≥1 and ≥2, respectively), only 21.8% had a prescription 90 days prior to the study. CONCLUSION: Prevalence of VHD among individuals with AF increased from 1998 to 2010. Atrial fibrillation associated with aortic stenosis, MS, or mechanical valves (compared to AF without VHD) was associated with an excess absolute risk of stroke, SSE, and mortality, but anticoagulation was underused in the pre-direct oral anticoagulant (DOAC) era, highlighting need for urgent clarity regarding DOACs in AF and concomitant VHD.

17.
Arrhythm Electrophysiol Rev ; 8(3): 161-165, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31463053

RESUMO

The British Heart Rhythm Society's Clinical Practice Guidelines on the Management of Patients Developing QT Prolongation on Antipsychotic Medication are written for heart rhythm consultants, primary care physicians, specialist registrars, nurses and physiologists who may be requested to review ECGs or advise on cases where antipsychotic-induced QT prolongation is suspected or proven. The guidance is adapted from the latest Maudsley Prescribing Guidelines in Psychiatry, published in 2018.

18.
Pediatr Cardiol ; 40(8): 1553-1558, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31446474

RESUMO

The patterns and prevalence of early repolarization pattern (ER) in pediatric populations from ethnic backgrounds other than Caucasian have not been determined. Black African children (ages 4-12) from north-west Madagascar were prospectively recruited and their ECGs compared with those of age- and sex-matched Caucasian ethnicity individuals. ER was defined by ≥ 0.1 mV J-point elevation in at least two contiguous inferior and/or lateral ECG leads. A total of 616 children were included. There was a trend toward a higher frequency of ER in the Africans compared to the Caucasians (23.3% vs. 17.1%, respectively, p = 0.053). The subtype (slurred vs. notched) and location of ER (lateral, inferior, or inferior-lateral) were significantly different in the two groups (p < 0.001 and p = 0.020, respectively). There was no significant difference in the number of high-risk ECG features of ERP (i.e., horizontal/descendent pattern, inferior or inferior-lateral location or J-waves ≥ 2 mm) between African and Caucasian children. On the multivariate analysis, African ethnicity was an independent predictive factor of ER (OR 3.57, 95% CI 2.04-6.25, p < 0.001). African children have an increased risk of ER compared to Caucasian counterparts. Future studies should clarify the clinical and prognostic significance of ER in the pediatric population, and whether ethnicity has an impact on the outcomes.

19.
Am J Physiol Cell Physiol ; 317(3): C576-C583, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31291141

RESUMO

A murine line haploinsufficient in the cardiac sodium channel has been used to model human Brugada syndrome: a disease causing sudden cardiac death due to lethal ventricular arrhythmias. We explored the effects of cholinergic tone on electrophysiological parameters in wild-type and genetically modified, heterozygous, Scn5a+/- knockout mice. Scn5a+/- ventricular slices showed longer refractory periods than wild-type both at baseline and during isoprenaline challenge. Scn5a+/- hearts also showed lower conduction velocities and increased mean increase in delay than did littermate controls at baseline and blunted responses to isoprenaline challenge. Carbachol exerted limited effects but reversed the effects of isoprenaline with coapplication. Scn5a+/- mice showed a reduction in conduction reserve in that isoprenaline no longer increased conduction velocity, and this was not antagonized by muscarinic agonists.

20.
Am Heart J ; 214: 167-174, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31220775

RESUMO

In transvenous implantable cardioverter-defibrillator (TV-ICD) implants, routine defibrillation testing (DFT) does not improve shock efficacy or reduce arrhythmic death but patients are exposed to the risk of complications related to DFT. The conversion rate of DFT in subcutaneous ICD (S-ICD) is high and first shock efficacy is similar to TV-ICD efficacy rates. STUDY DESIGN: The PRAETORIAN-DFT trial is an investigator-initiated, randomized, controlled, multicenter, prospective two-arm trial designed to demonstrate non-inferiority of omitting DFT in patients undergoing S-ICD implantation in which the S-ICD system components are optimally positioned. Positioning of the S-ICD will be assessed with the PRAETORIAN score. The PRAETORIAN score is developed to systematically evaluate implant position of the S-ICD system components which determine the defibrillation threshold on post-operative chest X-ray. A total of 965 patients, scheduled to undergo a de novo S-ICD implantation without contra-indications for either DFT strategy, will be randomized to either standard of care S-ICD implantation with DFT, or S-ICD implantation without DFT but with evaluation of the implant position using the PRAETORIAN score. The study is powered to claim non-inferiority of S-ICD implantation without DFT in de novo S-ICD patients in respect to the primary endpoint of first shock efficacy in spontaneous arrhythmia episodes. Patients with a high PRAETORIAN score (≥90) in the interventional arm of this study will undergo DFT according to the same DFT protocol as in the control arm. CONCLUSION: The PRAETORIAN-DFT trial is a randomized trial that aims to gain scientific evidence to safely omit a routine DFT after S-ICD implantation in patients with correct device positioning.

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