Circulating intermediate CD14++CD16+monocytes are increased in patients with atrial fibrillation and reflect the functional remodelling of the left atrium.

AIMS: A recent large clinical study demonstrated the association between intermediate CD14++CD16+monocytes and cardiovascular events. However, whether that monocyte subset contributes to the pathogenesis of atrial fibrillation (AF) has not been clarified. We compared the circulating monocyte subsets in AF patients and healthy people, and investigated the possible role of intermediate CD14++CD16+monocytes in the pathophysiology of AF. METHODS AND RESULTS: This case-control study included 44 consecutive AF patients without systemic diseases referred for catheter ablation at our hospital, and 40 healthy controls. Patients with systemic diseases, including structural heart disease, hepatic or renal dysfunction, collagen disease, malignancy, and inflammation were excluded. Monocyte subset analyses were performed (three distinct human monocyte subsets: classical CD14++CD16-, intermediate CD14++CD16+, and non-classical CD14+CD16++monocytes). We compared the monocyte subsets and evaluated the correlation with other clinical findings. A total of 60 participants (30 AF patients and 30 controls as an age-matched group) were included after excluding 14 AF patients due to inflammation. Atrial fibrillation patients had a higher proportion of circulating intermediate CD14++CD16+monocytes than the controls (17.0 ± 9.6 vs. 7.5 ± 4.1%, P < 0.001). A multivariable logistic regression analysis demonstrated that only the proportion of intermediate CD14++CD16+monocytes (odds ratio: 1.316; 95% confidence interval: 1.095-1.582, P = 0.003) was independently associated with the presence of AF. Intermediate CD14++CD16+monocytes were negatively correlated with the left atrial appendage flow during sinus rhythm (r= -0.679, P = 0.003) and positively with the brain natriuretic peptide (r = 0.439, P = 0.015). CONCLUSION: Intermediate CD14++CD16+monocytes might be closely related to the pathogenesis of AF and reflect functional remodelling of the left atrium.

Predictors and Clinical Outcomes of Transient Responders to Cardiac Resynchronization Therapy.

BACKGROUND: Left ventricular end-systolic volume (LVESV) changes at 6 months and clinical status are useful for assessing responses to cardiac resynchronization therapy (CRT). Regression of the LVESV following CRT has not been described beyond 6 months. This study aimed to assess the proportion, predictors, and clinical outcomes of responders whose LVESVs had regressed. METHODS: We retrospectively analyzed 104 consecutive CRT patients. A responder was defined as a patient with a relative reduction in the LVESV ≥15% at 6 months after CRT. Fifty-six responders participated in this study. A transient responder was defined as a responder without a relative reduction in the LVESV ≥15% at 2 years after CRT or who died of cardiac events during the 24-month follow-up period. RESULTS: Of the 56 responders, 16 (29%) were transient responders. Multivariable logistic regression analysis showed that chronic atrial fibrillation (odds ratio [OR] = 19.2, 95% confidence interval [CI] [1.93, 190], P = 0.012) and amiodarone usage (OR = 60.9, 95% CI [4.18, 886], P = 0.003) were independent predictors of transient responses. Hospitalizations for heart failure were significantly higher among the transient responders than among the lasting responders during a mean follow-up period of 7.6 years (log-rank P < 0.001), and all-cause mortality tended to be higher among the transient responders (log-rank P = 0.093). CONCLUSIONS: One-third of the responders were transient responders at 2 years after CRT, and their long-term prognoses were poor. Careful attention should be paid to maintain the reduction in LVESV especially in patients with chronic AF.

Slit-Like Deformation of the Coronary Sinus Orifice due to Compression of the Inferior Pyramidal Space by the Severely Dilated Left Ventricle.

The coronary sinus is located within the inferior pyramidal space, which is the part of the epicardial visceral fibroadipose tissue wedging between the four cardiac chambers from the bottom of the heart. Therefore, this region is susceptible to the morphological changes of the cardiac chambers. We present a case of slit-like deformation of the coronary sinus orifice due to compression of the inferior pyramidal space by the severely dilated left ventricle, which has not been previously described.

Characteristics of Residual Atrial Posterior Wall and Roof-Dependent Atrial Tachycardias after Pulmonary Vein Isolation.

BACKGROUND: Roof-dependent atrial tachycardia (roof AT) sometimes occurs after pulmonary vein isolation (PVI) of atrial fibrillation (AF). This study aimed to investigate the relationship between the anatomy of the residual left atrial posterior wall and occurrence of roof AT. METHODS: A total of 265 patients with AF who underwent PVI were enrolled. After the PVI, induced or recurrent roof AT was confirmed by an entrainment maneuver or activation mapping using a three-dimensional (3D) mapping system. To identify the predictors of roof AT, the minimum distance between both PVI lines (d-PVI) was measured by a 3D mapping system and the anatomical parameters, including the left atrial (LA) diameter, left atrial volume index (LAVi), and shape of the left atrial roof, were analyzed by 3D computed tomography. RESULTS: Roof AT was documented in 11 (4.2%) of 265 patients. A multivariable analysis demonstrated that the d-PVI, Deep V shape of the LA roof, and LAVi were associated with roof AT occurrences (d-PVI: odds ratio: 0.72, confidence interval [CI]: 0.61-0.86, P < 0.001; Deep V shape: odds ratio: 0.19, CI: 0.04-0.82, P = 0.03; LAVi: odds ratio: 1.05, CI: 1.02-1.07, P = 0.001). A receiver-operating characteristic curve analysis yielded an optimal cut-off value of 15.5 mm and 55.7 mL/m2 for the d-PVI and LAVi, respectively. CONCLUSION: The shorter d-PVI at the LA roof, greater LAVi, and Deep V shape were associated with the occurrence of a roof AT.

The Relationship Between Cardiac Vulnerability and Restitution Properties of the Ventricular Activation Recovery Interval.

INTRODUCTION: The restitution of the action potential duration (APD) is an important contributor to ventricular fibrillation (VF) initiation by a single critically timed ectopic beat. We hypothesized that a steep slope of the activation recovery interval restitution curve was related to the upper limit of vulnerability (ULV). METHODS AND RESULTS: Fifty-four consecutive patients with implantable cardioverter defibrillators (ICDs) implanted between April 2012 and July 2013 were included. At the implantation, pacing from the right ventricular (RV) coil to an indifferent electrode inserted in the ICD pocket was performed, and the unipolar electrograms from the RV coil were simultaneously recorded. We assessed the standard restitution by introducing extra-stimuli, while measuring the activation recovery interval (ARI). Our protocol for the vulnerability test consisted of delivering three 15 J shocks on the T-peak and within ±20 milliseconds of it. If VF was not induced by that procedure, a ULV of ≤15 J was defined. The relationship between the ULV and maximum slope of the restitution curve was analyzed. A restitution curve could finally be obtained in a total of 40 patients. The background characteristics were similar between the two groups. The maximum slope of the restitution curve was steeper in the ULV > 15 J group than ULV ≤ 15 J group (1.55 ± 0.45 vs. 0.91 ± 0.64, P < 0.05). A maximum slope exceeding 1.0 was the optimal point for discriminating patients with a ULV > 15 J from a ULV ≤ 15 J (sensitivity 61.5% and specificity 96.3%). CONCLUSION: The maximum slope of the restitution curve was significantly related to the ULV. High defibrillation threshold patients could be detected by the ARI dynamics.

Crista Terminalis as the Anterior Pathway of Typical Atrial Flutter: Insights from Entrainment Map with 3D Intracardiac Ultrasound.

BACKGROUND: The precise location of truly active reentry circuits of typical atrial flutter (AFL) has not been well identified. The purpose of this study was to verify our hypothesis that the posterior block line is located along the posteromedial right atrium (PMRA) and the crista terminalis (CT) is the anterior pathway of AFL, with real-time intracardiac echo (ICE). METHODS: The entire right atrium (RA) three-dimensional activation and entrainment mapping were evaluated during AFL in 18 patients using CARTO sound. RESULTS: The CT was clearly visualized by ICE and the local electrograms along the CT were single potentials in all the patients. The CT was recognized as the truly active anterior pathway based on entrainment mapping in all patients. Double potentials were recorded along the PMRA. Entire RA entrainment mapping could be performed in 16 patients. The reentry circuits were separated into three passages. The first was around the tricuspid annulus (TA), the second the anterior superior vena cava (SVC; AFL waves passed between the anterior SVC and RA appendage), and the last the posterior SVC (between the posterior SVC and upper limit of the PMRA). All three of these passages were active in four, around the TA and anterior SVC in eight, around the TA and posterior SVC in three, and around only the anterior SVC in one patient. CONCLUSIONS: The CT functions as the anterior pathway of typical AFL, and the posterior block line was located along the PMRA. Dual or triple circuits were recognized in the majority of AFL patients.

Upper limit of vulnerability during defibrillator implantations predicts the occurrence of appropriate shock therapy for ventricular fibrillation.

BACKGROUND: The utility of the upper limit of vulnerability (ULV) test in patients undergoing defibrillator implantation has been reported, so the purpose of this study was to evaluate the difference in the clinical outcomes between patients with ULV ≤15 J or >15 J. METHODS AND RESULTS: A total of 165 patients receiving an implantable cardioverter-defibrillator underwent a vulnerability test. At the time of the implantation, we delivered a 15-J shock on the T-peak and ±20 ms later to cover the most vulnerable part of the cardiac cycle. The clinical outcomes were prospectively analyzed. A 15-J shock induced ventricular fibrillation (VF) in 30 patients (ULV >15 J) and did not in 135 (ULV ≤15 J). The characteristics of the 2 groups were comparable. After a mean follow-up of 757 days, Kaplan-Meier curve analysis showed that the ULV ≤15 J group experienced less VF than the ULV >15 J group (log-rank P=0.003). The occurrence of ventricular tachycardia was similar between the 2 groups (P=0.140). Furthermore, the effectiveness of ATP was comparable. After adjusting for other known predictors of shock therapy, a ULV >15 J was independently associated with the occurrence of VF (hazard ratio: 6.25; 95% confidence interval: 1.913-20.40; P<0.01). CONCLUSIONS: A high ULV value was associated with a high incidence of VF, which suggests that cardiac vulnerability to electrical shock may be linked to electrical instability.

Visualization of the antegrade fast and slow pathway inputs in patients with slow-fast atrioventricular nodal reentrant tachycardia.

INTRODUCTION: Mapping of the antegrade fast pathway (A-FP) exact sites and antegrade slow pathway (A-SP) input locations has not been well described. METHODS: In 56 patients with slow-fast atrioventricular nodal reentrant tachycardia (SF-AVNRT), pacing during sinus rhythm and entrainment pacing during SF-AVNRT were performed at various sites in the triangle of Koch and coronary sinus (CS) to identify the A-FP and A-SP inputs. User-defined three-dimensional electro-anatomical mapping of the stimulus-His potential (St-H) interval and anatomical location was performed. The A-FP input was defined as the site of the shortest St-H interval, and A-SP input as the site of the shortest St-H interval and with a postpacing-interval equal to the tachycardia cycle length. The locations of the A-FP and A-SP inputs were mapped as a ratio of the distance between the His bundle (HB) and CS orifice (CSO), and the HB-CSO axis was divided into three zones: superior-, mid-, and inferior septum. The distance between the A-SP and A-FP inputs was calculated using the distance from each input to the HB and HB-CSO axis. RESULTS: Only 30 patients were included in this study because the A-SP mapping failed in 26. The A-SP input was distributed to the superior septum in four, mid- or inferior septum in 25, and CS in one. An A-SP input which was located less than 10 mm from the A-FP input was observed in one of four patients with a superior septum A-SP. CONCLUSIONS: An A-SP input at the superior septum seemed to be a potential risk for atrioventricular nodal injury during ablation.

Pulmonary tumor thrombotic microangiopathy showing aggressive course after transurethral resection of urinary bladder: an autopsy case report.

A 77-year-old man developed pulmonary tumor thrombotic microangiopathy (PTTM) 2 days after undergoing transurethral resection for urothelial carcinoma (G3) of the urinary bladder and died of respiratory failure 6 days later. Histological findings demonstrated marked intimal fibrocellular proliferation, fibrin thrombi, and both cancer cells and fibrin thrombi in the arteries of the lungs, findings consistent with PTTM. Prominent stenosis in arteries smaller than 300 µm was also seen. The Ki-67 labeling index of primary and metastasized cancer cells was 62.4 % and 70.2 %, respectively. The membranes of metastasized cancer cells expressed E-cadherin, similar to membranes in the urinary bladder. An aggressive PTTM course is affected by intimal fibrocellular proliferation and the high cell proliferation of cancer cells. Furthermore, prominent stenosis in small arteries and membranous staining of E-cadherin of metastasized cells suggest that cancer cells formed clusters by maintaining adhesion molecules and migrated into the arteries of the lungs, where they easily caused damage to the endothelium of small arteries, in contrast to dispersed cancer cells.

Percutaneous Pericardiocentesis With the Anterior Approach: Demonstration of the Precise Course With Computed Tomography.

OBJECTIVES: This study aimed to confirm the precise course of a pericardiocentesis with the anterior approach using post-procedural computed tomography (CT). BACKGROUND: Percutaneous epicardial ventricular tachycardia (VT) ablation has been increasingly performed. Although the inferior approach has been the common method, the feasibility of the anterior approach has subsequently been reported. However, the precise course of the anterior approach has not been presented. METHODS: An epicardial ablation with the anterior approach was performed in 15 patients. At the end of the procedure, the epicardial sheath was exchanged for a drainage tube to monitor bleeding. Of those patients, in 9 procedures in 8 patients a CT scan was performed just after the procedure to confirm the course of the drainage tube and to rule out any complications. Epicardial ablation was indicated for a failed endocardial VT ablation in 7 patients and epicardial substrate modification in 1 patient with Brugada syndrome. RESULTS: Volume-rendered images reconstructed from CT demonstrated each course of the drainage tubes and their relation to the surrounding organs. These images revealed that the tube had a curved trace, and did not penetrate the diaphragm or pass through the abdominal cavity. No injury to the surrounding organs was detected in any of the cases. CONCLUSIONS: The precise course of the drainage tube placed along the trajectory of the anterior approach was able to be confirmed using post-procedural CT images. These images support the safety and feasibility of the anterior approach from the anatomic standpoint with a low incidence of abdominal viscera injury.

Trans-aortic pulmonary vein isolation using magnetic navigation system for paroxysmal atrial fibrillation in a patient with dextrocardia, situs inversus, and inferior vena cava continuity with azygos vein.

A 51-year-old male with dextrocardia and situs inversus underwent catheter ablation for paroxysmal atrial fibrillation. Because the procedure through the trans-septal approach was impossible due to the inferior vena cava continuity with azygos vein, we performed pulmonary vein isolation using magnetic navigation system through the retrograde trans-aortic approach. Superior and inferior left-sided and superior right-sided pulmonary veins could be isolated which was confirmed by the ablation catheter. The patient was free from atrial fibrillation episode at the 12 months follow-up except only one palpitation episode lasting nearly 12 hours at 9 months after the ablation.

The lesion characteristics assessed by LGE-MRI after the cryoballoon ablation and conventional radiofrequency ablation.

Background: Rhythm outcomes after the pulmonary vein isolation (PVI) using the cryoballoon (CB) are reported to be excellent. However, the lesions after CB ablation have not been well discussed. We sought to characterize and compare the lesion formation after CB ablation with that after radiofrequency (RF) ablation. Methods: A total of 42 consecutive patients who underwent PVI were enrolled (29 in the CB group and 13 in the RF group). The PVI lesions were assessed by late gadolinium enhancement magnetic resonance imaging 1-3 months after the PVI. The region around the PVs was divided into eight segments: roof, anterior-superior, anterior-carina, anterior-inferior, bottom, posterior-inferior, posterior-carina, and posterior-superior segment. The lesion width and lesion gap in each segment were compared between the two groups. Lesion gaps were defined as no-enhancement sites of >4 mm. Results: As compared to the RF group, the overall lesion width was significantly wider and lesion gaps significantly fewer at the anterior-superior segment of the left PV (LAS) and anterior-inferior segment of the right PV (RAI) in the CB group (lesion width: 8.2 ± 2.2 mm vs 5.6 ± 2.0 mm, P = .001; lesion gap at LAS: 7% vs 38%, P = .02; lesion gap at RAI: 7% vs 46%, P = .006). Conclusions: The PVI lesions after CB ablation were characterized by extremely wider and more continuous lesions than those after RF ablation.

The details of an unusual "ghost" after transvenous lead extraction: Three-dimensional computed tomography analysis.

Transvenous lead extraction (TLE) is performed to prevent deaths in patients with device infections. Intracardiac masses detected by echocardiography, i.e., "ghosts," are reported in 8% of patients after a TLE in retrospective studies and in 14% in prospective studies. We herein describe a case with unusual ghosts after a TLE. Three-dimensional computed tomography (3DCT) is useful for revealing all the details of unusual ghosts. In this case, the residual silicone insulation and "cast," including the fibrous sheath and severe calcifications could be visualized and differentiated by 3DCT.

Anatomical dilatation of the superior vena cava associated with an arrhythmogenic response induced by SVC scan pacing after atrial fibrillation ablation.

BACKGROUND: The relationship between pulmonary vein (PV) arrhythmogenicity and its anatomy has been reported. However, that of the superior vena cava (SVC) has not been well discussed. Arrhythmogenic response induced by pacing stimulation at SVC might help with identifying SVC arrhythmogenicity. The purpose of this study was to investigate the relationship between the anatomical dilatation of SVC and the arrhythmogenic response induced by pacing at SVC. METHODS: Forty-three patients who underwent atrial fibrillation (AF) ablation were enrolled in this study. After PV isolation, scan pacing (up to triple extra stimulation following intrinsic sinus beats) was performed at SVC. The arrhythmogenic response was defined as following: (1) repetitive atrial responses, (2) non-sustained, and (3) sustained AF/ atrial tachycardia. To assess the dilatation of SVC, we measured the cross-sectional area of the SVC (SVC-area) using multi-planar reconstruction CT imaging. RESULTS: Arrhythmogenic responses were documented in 24 patients (Group 1). No arrhythmogenic responses were documented in the remaining 19 patients (Group 2). The SVC-area was significantly larger in Group 1 than Group 2 (3.1±0.9 vs. 2.2±0.8 cm2, P=0.004). A multivariate analysis revealed only SVC-area was associated with arrhythmogenic responses (odds ratio=2.87, CI 1.05-7.82, P=0.04). Furthermore, AF recurrence rate was significantly higher in patients with SVC-area>2.56 cm2 than those with SVC-area <2.56 cm2 (9 [42.9%] of 21 vs. 3 [13.6%] of 22, P=0.026). CONCLUSION: Dilatation of SVC was associated with an arrhythmogenic response, and the AF recurrence rate was significantly higher in patients with large SVC-area. Adjunctive catheter intervention for the SVC might be indicated in patients with a dilated SVC and an arrhythmogenic response.