Taming the Tiger: Partial Input Block Results in a Stable, Organized Coronary Sinus Activation During Atrial Fibrillation.

In this manuscript, we present a case where coronary sinus activation was organized and stable despite the rhythm being atrial fibrillation. We discuss the possible mechanisms of this rare occurrence.

Bipolar radiofrequency ablation between middle cardiac vein and left ventricular endocardium for intramural ventricular tachycardia originating from the left ventricular inferobasal septum.

Ventricular tachycardia ablation in the post-surgical patients is complicated by difficult epicardial access. Endocardial-only ablation may lead to failure which can be prevented by mapping and ablating inside the coronary venous system. Radiofrequency ablation inside the coronary venous system is dependent on anatomical and biophysical factors. Herein we report a ventricular tachycardia case necessitating bipolar ablation between the middle cardiac vein and the left ventricular endocardium.

Long-term follow-up of patients undergoing add-on pacing/sensing lead vs. ICD lead implantation for failed IS-1/DF-1 ICD leads: a single centre experience.

BACKGROUND: Intracardiac defibrillator/cardioverter (ICD) is a cornerstone device for prevention of sudden cardiac death. Lead failure (LF) is one of the most important long-term complications. In this study, we sought to investigate mid-to-long term clinical, device and lead characteristics of patients who have undergone pacing sensing lead (PSL) implantation for an ICD LF and compare them to the patients who have undergone a new ICD lead implantation. METHODS: In this retrospective, single centre, case-control study, we have screened all ICD patients presenting with LF. Patients with IS-1/DF-1 ICD leads with intact high-voltage conductor were included in the study group, while other patients were included in the control arm. Study group patients underwent PSL implantation, control group patients underwent ICD lead implantation. RESULTS: Thirty patients were included in each arm of the study. The mean duration of follow-up after intervention was similar in both groups (47.6 months ± 20.4 vs. 46.1 months ± 25.7, p = .808). The total failure rate was not different between two groups (p = .640). Rate of high-voltage conductor disfunction was also similar between two arms: 1 (3.3%) in PSL arm and 0 in control arm (p = .303). CONCLUSIONS: Addition of a PSL for IS-1/DF-1 ICD LF with normal high-voltage conductor measurements is a viable treatment option with similar long-term results to addition of a new ICD lead. This approach is potentially less costly, technically less demanding, and, in case of concomitant extraction procedure, associated with less acute complication risk.

Cardioneuroablation for carotid sinus syndrome mediated by complete atrioventricular block.

Carotid sinus syndrome (CSS) is a rare condition leading to recurrent syncope. Permanent pacemaker implantation is the mainstay treatment of cardioinhibitory CSS. In this report, we present a CSS patient with reproducible atrioventricular block during carotid massage, who was treated with cardioneuroablation.

Electrophysiological characteristics of epicardial atrial tachycardias and endocardial breakthrough site targeting for ablation: a single center experience.

BACKGROUND: Despite being increasingly observed in daily practice, epicardial atrial tachycardias (Epi AT) have not been extensively characterized. In the present study, we retrospectively characterize electrophysiological properties, electroanatomic ablation targeting, and outcomes of this ablation strategy. METHODS: Patients who underwent scar-based macro-reentrant left atrial tachycardia mapping and ablation patients with at least one Epi AT, which had a complete endocardial map, were selected for the inclusion. Based on current electroanatomical knowledge, Epi ATs were classified based by utilization of following epicardial structures: Bachmann's bundle, septopulmonary bundle, vein of Marshall. Endocardial breakthrough (EB) sites were analyzed as well as entrainment parameters. EB site was targeted for initial ablation. RESULTS: Among seventy-eight patients undergoing scar-based macro-reentrant left atrial tachycardia ablation, fourteen (17.8%) patients met the inclusion criteria for Epi AT and were included in the study. Sixteen Epi ATs were mapped, four utilizing Bachmann's bundle, five utilizing septopulmonary bundle, and seven utilizing vein of Marshall. Fractionated, low amplitude signals were present at EB sites. Rf terminated the tachycardia in ten patients; activation changed in five patients and in one patient atrial fibrillation ensued. During the follow-up, there were three recurrences. CONCLUSIONS: Epicardial left atrial tachycardias are a distinct type of macro-reentrant tachycardias that can be characterized by activation and entrainment mapping, without need for epicardial access. Endocardial breakthrough site ablation reliably terminates these tachycardias with good long-term success.

Stepwise mapping and ablation algorithm in patients undergoing ablation of unstable, unmappable scar-based atrial tachycardias.

BACKGROUND: Scar based atrial tachycardia (AT)'s usually presents with a complex electrophysiological substrate. It is not uncommon that multiple instable ATs are present in a single patient. The aim of this study was to analyze clinical and electrophysiological characteristics of patients who had undergone ablation for instable ATs, and report outcomes of the stepwise substrate ablation procedure during the follow-up. METHODS: Patients scheduled to undergo AT ablation were screened for enrollment to the study. When instable ATs were diagnosed a stepwise mapping and ablation algorithm was applied to all patients. After the procedure, patients were clinically and electrocardiographically followed. RESULTS: Twenty-six patients were enrolled in the study. The mean number of ATs observed during the procedures is 3.1±0.7. At the end of the procedure, 18 (69.2%) patients had isolated posterior wall. Anterior mitral line ablation was successfully performed in 13 (50%), mitral isthmus line in 4 (15.4%), roof line in 4 (15.4%) patients. The mean follow-up was 13.5±5.4 months. During the follow-up period 6(23.1%) patients developed arrhythmia recurrence. CONCLUSIONS: A reasonable mid-term success can be expected in patients with instable ATs undergoing ablation according to the stepwise substrate modification algorithm, however due to extensive ablation it should be reserved for patients where conventional activation mapping cannot be performed.

Relationship between left atrial scar and P wave dispersion in patients undergoing atrial fibrillation catheter ablation.

BACKGROUND: Left atrial scar is an important entity in the atrial fibrillation substrate. P wave dispersion (PWD) is an indicator of slow and inhomogeneous conduction in the atria. In this study, we aim to investigate the relation between PWD and left atrial scars identified by electroanatomical mapping. METHODS: Patients who had an electroanatomical map obtained during sinus rhythm as well as at least one electrocardiogram in sinus rhythm prior to the procedure were included in the study. Left atrial scar (defined as <0.5 mV) area was calculated on the electroanatomical map. Maximum and minimum P wave duration and PWD were compared between patients with and without left atrial scar. RESULTS: A total of 224 patients were enrolled in the study. Of them, 47.9% of the patients were female. On the electroanatomical map, left atrial scar was identified in 103 patients, and no scar was present in 121 patients. PWD was significantly increased in patients with left atrial scar when compared to the no-scar group (46 ms ± 20 vs. 38 ms ± 15, respectively, p < 0.001). Similarly, PWD was significantly increased in patients with moderate-to-severe scar, when compared to patients with mild scar (50 ms ± 19 vs. 41 ms ± 19, respectively, p = 0.026). PWD was found not to be a good predictor of left atrial scar with an AUC of 0.625 for scar vs. no scar. CONCLUSION: PWD is significantly increased in patients with left atrial scar identified by electroanatomical mapping, however, the receiver operating characteristic analysis showed that PWD is not a good predictor of presence of left atrial scar.

Association between Demodex folliculorum and Metabolic Syndrome.

BACKGROUND: Demodex folliculorum mite infestation is associated with many diseases such as rosacea, pityriasis found with acne vulgaris, and blepharitis. AIM: In this research, the aim of this study was to investigate an association between patients who have metabolic syndrome and presence of Demodex folliculorum. PATIENTS/METHODS: This research was planned prospectively as a case-control study. Fifty cases who have metabolic syndrome and 50 control subjects in good health were included. Metabolic syndrome was diagnosed according to the NCEP Adult Treatment Panel III criteria. Standard superficial skin biopsy was performed for the presence of Demodex folliculorum mite infestation. RESULTS: It was detected that number of Demodex affected from the glucose level and each increase in glucose level cause an increase on Demodex as 0.190 (P = .00, t = 4.746, B = 0.190, r = 0.57, Durbin-Watson = 1.801, confidence interval = 0.110 to 0.271 (for glucose)). CONCLUSION: In this study, the presence of Demodex folliculorum was found to be higher in the cases who have metabolic syndrome compared to the healthy group. These results show that in cases with metabolic syndrome, high blood sugar levels make them more susceptible to infestation of Demodex folliculorum.

Late elimination of challenging idiopathic ventricular arrhythmias originating from left ventricular summit by anatomical ablation.

Ablation of premature ventricular complexes (PVCs) originating from left ventricular outflow tract (LVOT)/left ventricular summit (LVS) is challenging with considerable rate of failure. Recently, in a novel approach to ablation of these arrythmias, application of radiofrequency energy to anatomically opposite sites of presumed origin of arrythmia, has been associated with moderate procedure success. Although late elimination of PVCs that are persistent following an ablation procedure has been previously reported, this observation has not been studied sufficiently. In this report, firstly, we present three cases of lately eliminated LVS PVCs, then, we discuss possible mechanism of this observation and conclude that after an initial failed attempt of anatomic ablation, operators may choose a period of watchful waiting before attempting a redo procedure.

Serum neuron-specific enolase, a marker of neuronal injury, increases after catheter ablation of atrial fibrillation.

OBJECTIVE: Catheter ablation of atrial fibrillation (AF) can lead to thromboembolic complications, especially stroke. We measured the periprocedural serum neuron-specific enolase (NSE) level, which is a biomarker of neuronal injury, after ablation of AF. METHODS: Forty-three patients with paroxysmal AF were prospectively enrolled before radiofrequency ablation. A neurological examination was performed before and after the procedure. The serum NSE level was determined before and at the end of the procedure and at 2, 24, and 48 h after the procedure. RESULTS: No patients developed new neurological deficits. However, the median (interquartile range) NSE level increased after ablation from 6.7 (3.87) ng/mL at baseline to 11.48 (5.3) ng/mL at 24 h postoperatively. The NSE level exceed the upper reference limit of normal (17 ng/mL) in 14 patients (33%), and these patients were found to have a larger left atrium. CONCLUSIONS: Serum NSE increased in most of the patients undergoing ablation for AF, and it exceeded the normal limit in one-third of the patients. Although NSE is a biomarker of neuronal injury, the clinical importance of this increase after AF ablation and its relationship with the left atrial diameter should be evaluated in a longitudinal study.

Evaluation of right ventricular pacing parameters in patients with proliferative scar.

BACKGROUND: Dermal and myocardial injury results in a healing process, characterized by inflammation and fibrosis. We aimed to investigate association between proliferative scarring at the operation site and right ventricular (RV) pacing and sensing parameters, two clinical outcomes associated with impaired dermal and myocardial healing, respectively. METHODS: We performed an observational retrospective study among regularly followed pacemaker (PM)/implantable cardioverter defibrillator (ICD)-implanted patients at our medical center. Patients, who had a first RV active fixation PM/ICD lead implantation procedure and a minimum follow-up of 1 year, were included in the study. Redo procedures, passive fixation RV leads, epicardial leads, generator replacement procedures, and patients using class I and III anti-arrhythmic drugs were excluded. Patients in the control group, matched by age, sex and implanted device and lead type, were randomly selected from the patient pool. Lead impedance, pacing threshold, and R wave measurements obtained at baseline and at 3rd, 6th, and 12th month were analyzed. RESULTS: Baseline characteristics of study and control groups were similar. While baseline and follow-up lead impedance and R wave measurements along with baseline and 3rd-month pacing thresholds showed no significant difference between two groups, 6th- and 12th-month pacing thresholds revealed statistically significant increase in proliferative scar group compared to control group (0.87 vs 0.72 p = 0.003 and 0.87 vs 0.71 p = 0.003, respectively). CONCLUSIONS: PM/ICD-implanted patients with proliferative scar on pocket wound may show increased RV pacing thresholds compared to patients with normal healing of pocket wound.

Effect of radiofrequency on epicardial myocardium after ablation of ventricular arrhythmias from within coronary sinus.

BACKGROUND: Radiofrequency (RF) ablation of idiopathic ventricular arrhythmias (IVA) from the coronary venous system (CVS) has been increasingly performed, but real effect of ablation lesions from CVS on epicardial myocardium has not been studied. OBJECTIVE: To compare effects of RF delivered inside the distal CVS during ablation of IVAs originating from left ventricular summit (LVS) with IVAs ablated from right ventricular outflow tract (RVOT) using cardiac magnetic resonance imaging (CMRI). METHODS: Twenty consecutive patients with IVAs who underwent acutely successful RF ablation at initial appropriate sites, i.e., distal CVS (Group 1, n = 10) or RVOT (Group 2; n = 10) were enrolled. Detailed contrast-enhanced CMRI of each patient was performed 3 months later. Presence and location of scars, distance of CVS to epicardial ventricular myocardium were measured and analyzed. RESULTS: Group 1 consisted of 10 and Group 2 consisted of 10 patients. Three months after the ablation, only three patients in Group 1 had detectable late gadolinium enhancement (LGE) on CMRI while nine out of 10 patients in Group 2 had evident LGE on CMRI (P: 0.02). The mean distance of distal CVS to epicardial anterobasal myocardium was measured to be 8.8 ± 1.6 mm in Group 1. In three cases that had detectable scar on superior anterobasal LV epicardium, the mean distance was 7.4 ± 1.1 mm. CONCLUSIONS: RF delivery inside the CVS is less likely to produce detectable LGE on CMRI compared to RVOT. This may partially explain less than ideal long-term results after ablation of LVS IVAs from within the great cardiac vein/anterior interventricular vein.

Extrathoracic subclavian-axillary vein location and morphological features over the first rib for pacemaker and defibrillator lead implantation.

BACKGROUND: We aimed to describe the variations of extrathoracic subclavian-axillary vein location and its morphology over the first rib by venography in order to facilitate venous puncture using fluoroscopic landmarks without contrast venography, and evaluate the success rate of punctures, which is made with our method. METHODS: Patients who had undergone de novo lead implantation with the help of prepuncture venography between 2011 and 2015 were enrolled. For detection of the segmental location of the axillary vein, the zones were defined (Zone 1: Posterior, Zone 2: Lateral, Zone 3: Medial) at the first rib by fluoroscopy. Additionally, patients, who underwent venous puncture with our method after January 2017, were evaluated in terms of puncture success. RESULTS: Four hundred thirty-three patients who had prepuncture contrast venography for defibrillator or pacemaker lead implantation in 2011-2015 were analyzed. The most common position of the axillary vein was found to be over zone 2 (91%) while the zone 1 location was 8.5% and the zone 3 was 0.5%. Venous valves were detected on the first rib in 98 patients. After January 2017, venous puncture using fluoroscopic landmarks was performed to 171 patients. The punctures were successfully performed over zone 2 with our method in 90.7% of the patients. CONCLUSIONS: The most common radioanatomic position of the extrathoracic subclavian-axillary vein was observed at zone 2 according to our method and the probability of presence of venous valve over the first rib is 22%. Additionally, the success rate of puncture using fluoroscopic landmarks over zone 2 was 90.7%.

Ablation of parahisian premature ventricular extrasystoles by subtricuspid retrograde approach using inverted catheter technique: back to the anatomy.

This report illustrates a feasible and anatomical solution aiming to improve the success and decrease the possible hazards such as atrioventricular block during ablation of parahisian PVCs. We tried to illustrate the specific anatomy pertaining parahisian region and to explain a retrograde subvalvular catheter technique to overcome these procedural obstacles.

Transvenous extraction of a 26-year-old Accufix atrial lead using TightRail rotating dilator sheath.

With the increasing number of implanted pacemakers and implantable cardioverter defibrillators, removal is required more frequently. Presently described is the transvenous extraction of a 26-year-old Accufix atrial lead using a mechanical dilator sheath. A 50-year-old male patient was admitted to the clinic with a pacemaker pocket infection. The atrial lead was an Accufix Bipolar J-Atrial active fixation lead, a model that was recalled in 1994, after reports of 2 deaths and 2 nonfatal injuries related to protrusion of the J retention wire. Both the atrial and ventricular leads were extracted using a mechanical dilator sheath. The Pacemaker Lead Extraction with the Excimer Sheath (PLEXES) Trial reported that of the 57 Accufix leads randomized to a non-laser approach, only 47% were removed successfully, compared with 96% of laser-randomized cases. Since laser sheaths are not available in Turkey, use of a mechanical dilator sheath was required. To our knowledge, this is the oldest Accufix lead extracted with a non-laser sheath. During the extraction of the ventricular lead, the tip of the lead broke off inside the right ventricle and the residual part was left inside the heart. During 3 months of follow-up, no signs of infection or any other undesirable events were encountered.