Background: Impaired renal function and atrial fibrillation (AF) can form a vicious cycle. Although there have been reports on improved renal function in patients who undergo successful AF ablation, renal function in patients with recurrence of AF has not been studied separately. We explored the changes in renal function in AF patients with mild renal dysfunction after an index failed catheter ablation and the influencing factors. Methods: We retrospectively recruited non-valvular AF (NVAF) patients with mildly impaired renal function admitted for catheter ablation and readmitted due to recurrence of AF. The estimated glomerular filtration rate (eGFR) was calculated before the index procedure and during readmission. △eGFR was defined as the difference between eGFR readmission and eGFR baseline. The same calculation applied for △CHA2DS2-VASc score. The primary endpoint was improved renal function (△eGFR > 0) after AF catheter ablation in patients with atrial arrhythmia recurrence. Results: A total of 132 NVAF patients were included in this study. The mean eGFR at readmission was significantly increased compared with the eGFR at baseline before the index ablation procedure (P < 0.01). The multivariable Cox regression analysis showed that a lower △CHA2DS2-VASc score (HR: 0.416, P = 0.003) and paroxysmal recurrent atrial arrhythmia (HR: 2.965, P = 0.001) were associated with better renal function. Conclusion: In NVAF patients with mildly impaired renal function, even those with recurrence after the initial catheter ablation, we observed improvements in renal function, which was associated with a lower △CHA2DS2-VASc score and paroxysmal recurrent arrhythmia.

Introduction: Cardiac magnetic resonance (CMR) is the gold standard for evaluating myocardial fibrosis. Few studies have explored the association between ventricular arrhythmias (VAs) and fibrosis in apparently normal hearts. We aimed to investigate the association between the occurrence and morphology of VAs and left ventricular late gadolinium enhancement (LV-LGE) in patients without known structural heart diseases. Methods: This study enrolled 78 patients with apparently normal hearts who underwent simultaneous 24-h ambulatory Holter electrocardiogram (ECG) and CMR examinations. The presence and extent of LGE was determined using CMR imaging and compared based on occurrence and morphology of VAs. The clinical characteristics were also recorded and calculated. Results: LV-LGE was observed in 19 (37.3%) and 4 (14.8%) patients with and without VAs, respectively (P=0.039). It was more frequently observed in patients with polymorphic VAs (P=0.024) and ST-segment depression (P=0.001), and its extent was greater in polymorphic VAs than monomorphic VAs, with a difference that approached significance (P=0.055). In multivariate analyses adjusted for other clinical variables, the presence of ST-segment depression (HR: 8.83; 95% CI: 2.23-35.50; P=0.002), drinking (HR: 6.84; 95% CI: 1.63-28.56; P=0.008), and polymorphic VAs (HR: 25.24; 95% CI: 3.88-164.06; P=0.001) were associated with greater prevalence of LV-LGE. Conclusion: In this cohort of patients without structural heart diseases, myocardial fibrosis was associated with multiple VA morphologies and ST-segment depression on Holter ambulatory ECG measurements.

Aims Idiopathic epicardial ventricular arrhythmias (VAs) are clustered in the areas of the summit and crux. This study was to report a group of idiopathic epicardial VAs remote from the summit and crux areas. Methods In total, 9 patients (6 males, mean age 32±13 years) were enrolled. The locations were identified by epicardial mapping and ablation. The electrocardiographic and electrophysiological characteristics were compared to those of 9 patients who had VAs ablated at the opposite endocardial site. Results VAs were identified at the epicardium, with 4 patients had VAs located at the inferior wall, one at the anterior wall, one at the apex and 3 patients had VAs at the lateral wall. A “QS” type at the location-related leads was the only identified surface electrocardiogram indication suggesting epicardial origin (compared to that of the controls, 100% vs 0%, p<0.001). Endocardial and epicardial mapping revealed pre-maturities of -11±4 ms and -25±8 ms, respectively (VS. -28±8 ms revealed by endocardial mapping in control patients, p<0.001 and p=0.389, respectively). All of the study cases demonstrated an “rS” pattern in the endocardial unipolar electrogram. Acute and long-term successful ablation (a median of 11 months of follow-up) was achieved in all patients without complications. Conclusion A distinct group of idiopathic VAs remote from the summit and crux areas warranting ablation by a subxiphoid approach were identified. Morphological ECG features of a “QS” type among the location-related grouped leads combined with the mapping findings helped in the identification of the epicardial site of origin.

Background: Combination of endocardial and epicardial approach has improved the overall success rate of ventricular tachycardia (VT) ablation in patients with cardiomyopathy. However, the origins of some VTs are truly intramural or close to coronary arteries, which make this combined strategy either prone to failure or too risky. Objectives: This observational study aimed to explore the feasibility and efficacy of direct epicardial ablation combined with intramural ethanol injection via surgical approach for such VTs. Methods: Six consecutive patients with recurrent sustained VT refractory to combined endocardial and epicardial radiofrequency ablation were included. Direct epicardial access was achieved through limited left thoracotomy in 3 patients and median sternotomy in other 3 patients. Ablation was performed using irrigation catheter guided by electroanatomic mapping. Ethanol was injected in all patients to reinforce transmural lesions. The primary outcome was freedom of sustained VT determined by device interrogation and periodical 24h-holter recordings subsequently. Results: Over a median follow-up of 22 months (range, 6~65), all patients remained free of sustained VT. One patient died of pulmonary infection one year after the procedure. Conclusions: A hybrid strategy of surgical ablation combined with intramural ethanol injection is feasible and effective in patients with multiple failed percutaneous ablation attempts.