Nebojsa Mujovic

Prediction of very late arrhythmia recurrence after radiofrequency catheter ablation of atrial fibrillation: The MB-LATER clinical score

Reliable prediction of very late recurrence of atrial fibrillation (VLRAF) occuring >12 months after catheter ablation (CA) in apparently “cured” patients could optimize long-term follow-up and modify decision-making regarding the discontinuation of oral anticoagulant therapy. In a single-centre cohort of consecutive patients post radiofrequency AFCA, we retrospectively derived a novel score for VLRAF prediction. Of 133 consecutive post AFCA patients (mean age 56.9 ± 11.8 years, 63.9% male, 69.2% with paroxysmal AF) who were arrhythmia-free at 12 months (excluding 3-month “blanking period”), 20 patients expirienced a VLRAF during a 29.1 ± 10.1-month follow-up, with a 3-year cumulative VLRAF rate of 31.1%. The MB-LATER score (Male, Bundle brunch block, Left atrium ≥47 mm, Type of AF [paroxysmal, persistent or long-standing persistent], and ER-AF = early recurrent AF), had better predictive ability for VLRAF (AUC 0.782) than the APPLE, ALARMc, BASE-AF2, CHADS2, CHA2DS2VASc or HATCH score (AUC 0.716, 0.671, 0.648, 0.552, 0.519 and 0.583, respectively), resulted in an improved net reclassification index (NRI) of 48.6–95.1% and better identified patients with subsequent VLRAF using decision-curve analysis (DCA). The MB-LATER score provides a readily available VLRAF risk assessment, and performs better than other scores. Validation of the MB-LATER score in other cohorts is underway.

Preoperative pulmonary rehabilitation in patients with non-small cell lung cancer and chronic obstructive pulmonary disease

Introduction The aim of this study was to assess the effects of preoperative pulmonary rehabilitation (PPR) on preoperative clinical status changes in patients with chronic obstructive pulmonary disease (COPD) and non-small cell lung cancer (NSCLC), and net effects of PPR and cancer resection on residual pulmonary function and functional capacity. Material and methods This prospective single group study included 83 COPD patients (62 ±8 years, 85% males, FEV1 = 1844 ±618 ml, Tiffeneau index = 54 ±9%) with NSCLC, on 2–4-week PPR, before resection. Pulmonary function, and functional and symptom status were evaluated by spirometry, 6-minute walking distance (6MWD) and Borg scale, on admission, after PPR and after surgery. Results Following PPR significant improvement was registered in the majority of spirometry parameters (FEV1 by 374 ml, p < 0.001; VLC by 407 ml, p < 0.001; FEF50 by 3%, p = 0.003), 6MWD (for 56 m, p < 0.001) and dyspnoeal symptoms (by 1.0 Borg unit, p < 0.001). A positive correlation was identified between preoperative increments of FEV1 and 6MWD (r s = 0.503, p = 0.001). Negative correlations were found between basal FEV1 and its percentage increment (r s = –0.479, p = 0.001) and between basal 6MWD and its percentage change (r s = –0.603, p < 0.001) during PPR. Compared to basal values, after resection a significant reduction of most spirometry parameters and 6MWD were recorded, while Tiffeneau index, FEF25 and dyspnoea severity remained stable (p = NS). Conclusions Preoperative pulmonary rehabilitation significantly enhances clinical status of COPD patients before NSCLC resection. Preoperative increase of exercise tolerance was the result of pulmonary function improvement during PPR. The beneficial effects of PPR were most emphasized in patients with initially the worst pulmonary function and the weakest functional capacity.

Decision-Making in Clinical Practice: Oral Anticoagulant Therapy in Patients with Non-valvular Atrial Fibrillation and a Single Additional Stroke Risk Factor

Approximately 1 in 3–4 patients presenting with an ischemic stroke will also have atrial fibrillation (AF), and AF-related strokes can be effectively prevented using oral anticoagulant therapy (OAC), either with well-controlled vitamin K antagonists (VKAs) or non-vitamin K antagonist oral anticoagulants (NOACs). In addition, OAC use (both VKAs and NOACs) is associated with a 26% reduction in all-cause mortality (VKAs) or an additional 10% mortality reduction with NOACs relative to VKAs. The decision to use OAC in individual AF patient is based on the estimated balance of the benefit from ischemic stroke reduction against the risk of major OAC-related bleeding [essentially intracranial hemorrhage (ICH)]. Better appreciation of the importance of VKAs’ anticoagulation quality [a target time in therapeutic range (TTR) of ≥70%] and the availability of NOACs (which offer better safety compared to VKAs) have decreased the estimated threshold for OAC treatment in AF patients towards lower stroke risk levels. Still, contemporary registry-based data show that OAC is often underused in AF patients at increased risk of stroke. The uncertainty whether to use OAC may be particularly pronounced in AF patients with a single additional stroke risk factor, who are often (mis)perceived as having a “borderline” or insufficient stroke risk to trigger the use of OAC. However, observational data from real-world AF cohorts show that the annual stroke rates in such patients are higher than in patients with no additional stroke risk factors, and OAC use has been associated with reduction in stroke, systemic embolism, or death in comparison to no therapy or aspirin, with no increase in the risk of bleeding relative to aspirin. In this review article, we summarize the basic principles of stroke risk stratification in AF patients and discuss contemporary real-world evidence on OAC use and outcomes of OAC treatment in AF patients with a single additional stroke risk factor in various real-world AF cohorts.

Catheter ablation of lone atrial fibrillation

Atrial fibrillation is the most common sustained arrhythmia in clinical practice, associated with increased mortality, risk of stroke and heart failure, as well as the reduction of the quality of life. Atrial fibrillation may be encountered in young otherwise healthy individuals, due to the isolated electrophysiological disorder limited mostly to the pulmonary veins and posterior left atrial wall, or associated with the presence of advanced underlying heart disease and numerous cardiac and non-cardiac comorbidities with significant structural remodeling of the atrial myocardium. Due to limited efficacy and serious side effects of antiarrhythmic drugs, catheter ablation of atrial fibrillation, based on the pulmonary vein isolation for paroxysmal atrial fibrillation and adjunctive substrate modification for persistent atrial fibrillation, has emerged as an attractive and promissing alternative therapeutic option for selected patients with atrial fibrillation. In this review article, we discuss the electrophysiological left atrial abnormalities underlying lone atrial fibrillation and the role of pulmonary veins in pathophysiology of arrhythmia, and we summarize results of the studies on the long term outcome of catheter ablation of atrial fibrillation, as well as the studies on comparison of antiarrhythmic drugs with catheter ablation for treatment of atrial fibrillation. In addition, we present available data that provide better understanding of mechanisms, diagnosis, prevention and treatment of specific procedure-related complications and discuss current periprocedural anticoagulation strategies and their impact on the thromboembolic risk reduction.

Patient preferences at ten years following initial diagnosis of atrial fibrillation: the Belgrade Atrial Fibrillation Study.

Background Many atrial fibrillation (AF) patients have a poor understanding of the management of this condition. We investigated patient attitudes towards AF and a potential invasive treatment following an average 10-year period of prospective rhythm control in a cohort of newly diagnosed AF patients. Methods This was a prospective registry-based study. At the regular annual visit in 2007, patients were asked at random to answer several AF-related questions. Results Of 390 patients, 277 (71.0%) reported symptom reduction over time, but only 45 (11.5%) reported that they had “got used” to AF; 201 patients (51.5%) stated they would always prefer sinus rhythm, and 280 (71.2%) would accept an invasive AF treatment. Independent predictors for choosing an invasive procedure were younger age, impaired career/working capacity, and male gender (all P < 0.05). Conclusion Our findings suggest that most AF patients prefer sinus rhythm and would readily accept an invasive procedure if it offered the possibility of a cure for their AF.

Influence of Pulmonary Rehabilitation on Lung Function Changes After the Lung Resection for Primary Lung Cancer in Patients with Chronic Obstructive Pulmonary Disease

Influence of physiotherapy on the outcome of the lung resection is still controversial. Study aim was to assess the influence of physiotherapy program on postoperative lung function and effort tolerance in lung cancer patients with chronic obstructive pulmonary disease (COPD) that are undergoing lobectomy or pneumonectomy. The prospective study included 56 COPD patients who underwent lung resection for primary non small-cell lung cancer after previous physiotherapy (Group A) and 47 COPD patients (Group B) without physiotherapy before lung cancer surgery. In Group A, lung function and effort tolerance on admission were compared with the same parameters after preoperative physiotherapy. Both groups were compared in relation to lung function, effort tolerance and symptoms change after resection. In patients with tumors requiring a lobectomy, after preoperative physiotherapy, a highly significant increase in FEV1, VC, FEF50 and FEF25 of 20%, 17%, 18% and 16% respectively was registered with respect to baseline values. After physiotherapy, a significant improvement in 6-minute walking distance was achieved. After lung resection, the significant loss of FEV1 and VC occurred, together with significant worsening of the small airways function, effort tolerance and symptomatic status. After the surgery, a clear tendency existed towards smaller FEV1 loss in patients with moderate to severe, when compared to patients with mild baseline lung function impairment. A better FEV1 improvement was associated with more significant loss in FEV1. Physiotherapy represents an important part of preoperative and postoperative treatment in COPD patients undergoing a lung resection for primary lung cancer.

Persistency of left atrial linear lesions after radiofrequency catheter ablation for atrial fibrillation: Data from an invasive follow-up electrophysiology study

Data on the roof line (RL) and mitral isthmus line (MIL) reconnections after atrial fibrillation (AF) catheter ablation (CA) are scarce.

The Occurrence of New Arrhythmias after Catheter-Ablation of Accessory Pathway: Delayed Arrhythmic Side-Effect of Curative Radiofrequency Lesion?

INTRODUCTION New arrhythmias (NA) may appear late after accessory pathway (AP) ablation, but their relation to curative radiofrequency (RF) lesion is unknown. OBJECTIVE The aim of this study was to determine the prevalence and predictors for NA occurrence after AP ablation and to investigate pro-arrhythmic effect of RF. METHODS Total of 124 patients (88 males, mean age 43 +/- 14 years) with Wolff-Parkinson-White syndrome and single AP have been followed after successful RF ablation. Post-ablation finding of arrhythmia, not recorded before the procedure, was considered a NA. The origin of NA was assessed by analysis of P-wave and/or QRS-complex morphology, and, thereafter, it was compared with locations of previously ablated APs. RESULTS Over the follow-up of 4.3 +/- 3.9 years, NA was registered in 20 patients (16%). The prevalence of specific NAs was as follows: atrioventricular (AV) block 0.8%, atrial premature beats 1.6%, atrial fibrillation 5.4%, atrial flutter 0.8%, sinus tachycardia 4.8%, ventricular premature beats (VPBs) 7.3%. Multivariate Cox-regression analysis identified (1) pre-ablation history of pathway-mediated tachyarrhythmias >10 years (HR = 3.54, p = 0.016) and (2) septal AP location (HR = 4.25, p = 0.003), as the independent predictors for NA occurrence. In four NA cases (two cases of septal VPBs, one of typical AFL and one of AV-block) presumed NA origin was identified in the vicinity of previous ablation target. CONCLUSION NAs were found in 16% of patients after AP elimination. In few of these cases, late on-site arrhythmic effect of initially curative RF lesion might be possible. While earlier intervention could prevent NA occurrence, closer follow-up is advised after ablation of septal AP.

The relationship of early recurrence of atrial fibrillation and the 3-month integrity of the ablation lesion set

Early recurrence of atrial fibrillation (ERAF) after catheter-ablation (CA) can be a transient phenomenon due to inflammation, or a harbinger of late AF recurrence due to CA lesion (re)conduction. We studied the relationship between ERAF and the 3-month CA lesions integrity. Forty one consecutive AF patients who underwent a pulmonary vein isolation (PVI), roof line (RL) and mitral isthmus line (MIL) CA were enrolled. At 3 months all patients underwent invasive assessment of the lesion set integrity irrespective of ERAF. The PVI, RL and MIL ablation was successful in 100.0%, 95.1% and 82.9% patients, respectively. At the 3-month remapping, a gap in PVI-lesion(s), RL or MIL was identified in 61.0%, 31.7% and 36.6% patients, respectively. Patients with (n = 17, 41.5%) compared to those without ERAF (n = 24) had a significantly higher rate of any PV-reconnection (88.2% vs. 41.7%), the right PV(s)-reconnection (82.5% vs. 29.2%) and the RL gap (52.9% vs. 16.7%), as well as a higher number of reconnected right PVI-segments, all p < 0.05. On multivariate analysis, only the number of reconnected right PVI-segments was associated with ERAF (OR 4.26, p = 0.004). The ERAF following PVI + RL + MIL ablation was significantly related to 3-month PV-reconnections and the presence of RL gaps.

Validation of the MB-LATER score for prediction of late recurrence after catheter-ablation of atrial fibrillation

BACKGROUND Reliable identification of atrial fibrillation (AF) patients more likely to be AF-free long-term post-single catheter ablation (CA) would facilitate appropriate risk communication to patients. We validated the recently proposed MB-LATER score for prediction of late recurrences of AF (LRAF) post-CA. METHODS Patients who underwent CA for symptomatic AF refractory to ≥1 antiarrhythmic drugs at the Johns Hopkins Hospital, Baltimore, between March 2003 and December 2015, for whom ≥1-year post-CA follow-up data were available, were enrolled. RESULTS Of 226 patients (median age 58.5 years [IQR: 52.0-65.0], 163 males [72.1%], 142 [62.8%] with paroxysmal AF), LRAF occurred in 133 patients (58.8%) during a median 2-year follow-up (IQR: 1.1-4.1). The mean MB-LATER score was significantly higher in patients with versus those without LRAF (2.4 ± 1.2 vs. 1.9 ± 1.3, p = 0.002) and showed modest but significant predictive ability for LRAF (AUC: 0.62 [95% CI: 0.54-0.69], p = 0.003). A score cut-off value of >2 showed the best predictive ability for LRAF (70.4% [61.5-77.9]), with modest sensitivity (42.9% [34.3-51.7]) and specificity (74.2% [64.1-82.7]). Kaplan-Meyer survival free from AF was significantly better for patients with a MB-LATER score of ≤2 than for those with a score of >2 (log-rank p = 0.005). CONCLUSION In our study, the MB-LATER score showed a significant but modest predictive ability for LRAF post-AF ablation. Further prospective validation is needed to better define the potential role of the MB-LATER score in patient selection and treatment decision-making post-AF ablation.