A challenge of pulmonary vein isolation (PVI) in catheter ablation for paroxysmal atrial fibrillation (PAF) is electrical reconnection of the PV. EFFICAS I showed correlation between contact force ...(CF) parameters and PV durable isolation but no prospective evaluation was made. EFFICAS II was a multicentre study to prospectively assess the impact of CF guidance for an effective reduction of PVI gaps.
Pulmonary vein isolation using a radiofrequency (RF) ablation catheter with an integrated force sensor (TactiCath™) was performed in patients with PAF. Operators were provided EFFICAS I-based CF guidelines target 20 g, range 10-30 g, minimum 400 g s force-time integral (FTI). Conduction gaps were assessed by remapping of PVs after 3 months, and gap rate was compared with EFFICAS I outcome. At follow up, 24 patients had 85% of PVs remaining isolated, compared with 72% in EFFICAS I (P = 0.037) in which CF guidelines were not used. The remaining 15% of gaps correlated to the number of catheter moves at creating the PVI line, quantified as Continuity Index. For PV lines with contiguous lesions and low catheter moves, durable isolation was 81% in EFFICAS I and 98% in EFFICAS II (P = 0.005). At index procedure, the number of lesions was reduced by 15% in EFFICAS II vs. EFFICAS I.
The use of CF with the above guidelines and contiguous deployment of RF lesions in EFFICAS II study resulted in more durable PVI in catheter ablation of PAF.
The visually guided laser ablation (VGLA) catheter is a compliant, variable-diameter balloon that delivers laser energy around the pulmonary vein (PV) ostium under real-time endoscopic visualization. ...While acute PV isolation has been shown to be feasible, limited data exist regarding the durability of isolation.
We sought to determine the durability of PV isolation following ablation using the balloon-based VGLA catheter.
The VGLA catheter was evaluated in patients with paroxysmal atrial fibrillation (3 sites, 10 operators). Following transseptal puncture, the VGLA catheter was advanced through a 12-F deflectable sheath and inflated at the target PV ostium. Under endoscopic guidance, the 30° aiming arc was maneuvered around the PV and laser energy was delivered to ablate tissue in a contiguous/overlapping manner. At ∼3 months, all patients returned for a PV remapping procedure.
In 56 patients, 202 of 206 PVs (98%) were acutely isolated. At 105 ± 44 (mean ± SD) days, 52 patients returned for PV remapping at which time 162 of 189 PVs (86%) remained isolated and 32 of 52 patients (62%) had all PVs still isolated. On comparing the operators performing <10 vs ≥ 10 procedures, the durable PV isolation rate and the percentage of patients with all PVs isolated were found to be 73% vs 89% (P = .011) and 57% vs 66% (P = .746), respectively. After 2 procedures and 12.0 ± 1.9 months of follow-up, the drug-free rate of freedom from atrial fibrillation was 71.2%.
In this multicenter, multioperator experience, VGLA resulted in a very high rate of durable PV isolation with a clinical efficacy similar to that of radiofrequency ablation.
Complications of catheter ablation for atrial fibrillation (AF) are frequently related to vascular access. We hypothesized that ultrasound-guided (USG) venipuncture may facilitate the procedure and ...reduce complication rates.
We conducted a multicentre, randomized trial in patients undergoing catheter ablation for AF on uninterrupted anticoagulation therapy. The study enrolled consecutive 320 patients (age: 63 ± 8 years; male: 62%) and were randomized to USG or conventional venipuncture in 1:1 fashion. It was prematurely terminated due to substantially lower-than-expected complication rates, which doubled the population size needed to maintain statistical power. While the complication rates did not differ between two study arms (0.6% vs. 1.9%, P = 0.62), intra-procedural outcome measures were in favour of the USG approach (puncture time, 288 vs. 369 s, P < 0.001; first pass success, 74% vs. 20%, P < 0.001; extra puncture attempts 0.5 vs. 2.1, P < 0.001; inadvertent arterial puncture 0.07 vs. 0.25, P < 0.001; unsuccessful cannulation 0.6% vs. 14%, P < 0.001). Though these measures varied between trainees (49% of procedures) and expert operators, between-arm differences (except for unsuccessful cannulation) were comparably significant in favour of USG approach for both subgroups.
Ultrasound-guided puncture of femoral veins was associated with preferable intra-procedural outcomes, though the major complication rates were not reduced. Both trainees and expert operators benefited from the USG strategy. (www.clinicaltrials.gov ID: NCT02834221).
To investigate predictors of long-term outcomes after catheter ablation (CA) for ventricular tachycardia (VT) and the impact of electrical storm (ES) prior to index ablation procedures.
We studied ...consecutive patients with structural heart disease and VT (n = 328; age: 63±12 years; 88% males; 72% ischaemic cardiomyopathy; LVEF: 32±12%) who had undergone CA. According to presenting arrhythmia at baseline, they were divided into ES (n = 93, 28%) and non-ES groups. Clinical predictors of all-cause mortality were investigated and a clinically useful risk score (SCORE) was constructed.
During a median follow-up of 927 days (IQR: 564-1626), 67% vs. 60% of patients (p = 0.05) experienced VT recurrence in the ES vs. the non-ES group, respectively; and 41% vs. 32% patients died (p = 0.02), respectively. Five factors were independently associated with mortality: age >70 years (hazard ratio (HR): 1.6, 95% confidence interval (CI): 1.1-2.4, p = 0.01), NYHA class ≥3 (HR: 1.9, 95% CI: 1.2-2.9, p = 0.005), a serum creatinine level >1.3 mg/dL (HR: 1.6, 95% CI: 1.1-2.3, p = 0.02), LVEF ≤25% (HR: 2.4, 95% CI: 1.6-3.5, p = 0.00004), and amiodarone therapy (HR: 1.5, 95% CI: 1.0-2.2, p = 0.03). A risk SCORE ranging from 0-4 (1 point for either high-risk age, NYHA, creatinine, or LVEF) correlated with mortality. ES during index ablation independently predicted mortality only in patients with a SCORE ≤1.
Advanced LV dysfunction, older age, higher NYHA class, renal dysfunction, and amiodarone therapy, but not ES, were predictors of poor outcomes after CA for VT in the total population. However, ES did predict mortality in a low-risk sub-group of patients.
Device-based algorithms offer the potential for automated optimization of cardiac resynchronization therapy (CRT), but the process for accepting them into clinical use is currently still ad-hoc, ...rather than based on pre-clinical and clinical testing of specific features of validity. We investigated how the QuickOpt-guided VV delay (VVD) programming performs against the clinical and engineering heuristic of QRS complex shortening by CRT. A prospective, 2-center study enrolled 37 consecutive patients with CRT. QRS complex duration (QRSd) was assessed during intrinsic atrioventricular conduction, synchronous biventricular pacing, and biventricular pacing with QuickOpt-proposed VVD. The measurements were done manually by electronic calipers in signal-averaged and magnified 12-lead QRS complexes. Native QRSd was 174 ± 22 ms. Biventricular pacing with empiric AVD and synchronous VVD resulted in QRSd 156 ± 20 ms, a significant narrowing from the baseline QRSd by 17 ± 27 ms, P = 0.0003. In 36 of 37 patients, the QuickOpt algorithm recommended left ventricular preexcitation with VVD of 42 ± 18 ms (median 40 ms; interquartile range 30-55 ms, P <0.00001). QRSd in biventricular pacing with QuickOpt-based VVD was significantly longer compared with synchronous biventricular pacing (168 ± 25 ms vs. 156 ± 20 ms; difference 12 ± 11ms; P <0.00001). This prolongation correlated with the absolute VVD value (R = 0.66, P <0.00001). QuickOpt algorithm systematically favours a left-preexcitation VVD which translates into a significant prolongation of the QRSd compared to synchronous biventricular pacing. There is no reason to believe that a manipulation that systematically widens QRSd should be considered to optimize physiology. Device-based CRT optimization algorithms should undergo systematic mechanistic pre-clinical evaluation in various scenarios before they are tested in large clinical studies.
The aim of this study was to investigate the predictors of long-term clinical outcome of heart failure (HF) patients who survived first year after initiation of cardiac resynchronization therapy ...(CRT).
This was a single-center observational cohort study of CRT patients implanted because of symptomatic HF with reduced ejection fraction between 2005 and 2013. Left ventricle (LV) diameters and ejection fraction, New York Heart Association (NYHA) class, and level of N-terminal fragment of pro-brain natriuretic peptide (NT-proBNP) were assessed at baseline and 12 months after CRT implantation. Their predictive power for long-term HF hospitalization and mortality, and cardiac and all-cause mortality was investigated.
A total of 315 patients with left bundle branch block or intraventricular conduction delay who survived >1 year after CRT implantation were analyzed in the current study. During a follow-up period of 4.8±2.1 years from CRT implantation, 35.2% patients died from cardiac (19.3%) or non-cardiac (15.9%) causes. Post-CRT LV ejection fraction and LV end-systolic diameter (either 12-month value or the change from baseline) were equally predictive for clinical events. For NT-proBNP, however, the 12-month level was a stronger predictor than the change from baseline. Both reverse LV remodeling and 12-month level of NT-proBNP were independent and comparable predictors of CRT-related clinical outcome, while NT-proBNP response had the strongest association with all-cause mortality. When post-CRT relative change of LV end-systolic diameter and 12-month level of NT-proBNP (dichotomized at -12.3% and 1230 ng/L, respectively) were combined, subgroups of very-high and very-low risk patients were identified.
The level of NT-proBNP and reverse LV remodeling at one year after CRT are independent and complementary predictors of future clinical events. Their combination may help to improve the risk stratification of CRT patients.
This study evaluated hemodynamic feasibility and reproducibility of a new method for in vivo simulation of human atrial fibrillation (AF). The method was tested during sinus rhythm in 10 patients ...undergoing catheter ablation for AF. A simple electronic device was assembled that allowed triggering a cardiac stimulator by predefined series of RR intervals. Irregular RR interval sequences with a mean heart rate of 90/min and 130/min were obtained from ECG recordings of another patients with AF. Simultaneous atrioventricular pacing was delivered by catheters placed inside the coronary sinus and at the His bundle region. Hemodynamic effect of the simulated AF was assessed by invasive measurement of the left ventricular (LV) pressure, dP/dt, and Tau. Compared to regular pacing at the same mean heart rate, the simulated AF significantly impaired the LV both systolic and diastolic function. Repeated AF pacing in the same patients generated similar LV hemodynamics. The proposed method provides a realistic and reproducible in-vivo model of AF. It can be exploited for investigation of the hemodynamic consequences of AF in various patient populations.
The study was aimed at investigating the arterial stiffness assessed by aortic pulse wave velocity (PWV) in the presence of primary hyperparathyroidism (PH), with and without concomitant ...hypertension. Subsequently, we examined the effect of parathyroidectomy (PTX) on arterial stiffness. A total of 28 patients with PH and concomitant hypertension, and 16 with PH without hypertension were investigated in comparison with 28 essential hypertensive patients and 18 healthy controls, respectively. Patients were matched for age, blood pressure (BP), body mass index, lipid profile and fasting glucose. Six months after PTX, 15 patients were examined again (hypertensive as well as normotensive). PWV was obtained using the SphygmoCor applanation tonometer (AtCor Medical, West Ryde, Australia). PWV was significantly higher in patients with PH and hypertension when compared with patients with essential hypertension (10.1 vs. 8.5 ms(-1), P=0.013). PWV remained significant even after adjustment for age and BP (P=0.02). Similarly, PWV was significantly higher in PH patients without hypertension in comparison with healthy controls (7.6 vs. 5.8 ms(-1), P<0.001). Six months after surgery, in addition to a normalization of calcium metabolism, a significant decrease in systolic BP (131 vs. 123 mmHg, P=0.004) and PWV (9.1 vs. 8.5 ms(-1), P=0.024) was observed. After adjusting for BP reduction, the decrease in PWV appeared non-significant. Our data indicate that PH increases PWV as a marker of arterial stiffness, in both hypertensive and non-hypertensive patients. However, neither the calcium serum level nor the parathyroid hormone level has been associated with PWV. Specific treatment by PTX significantly decreases PWV, which may be determined primarily by improved BP control after surgery.
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