Multi-catheter cryotherapy for the treatment of resistant accessory pathways

OBJECTIVE

To investigate the utility of simultaneous multi-catheter cryotherapy for the treatment of APs that were previously resistant to standard radiofrequency (RF) catheter ablation.

BACKGROUND

Catheter ablation is established in the treatment of accessory pathways (AP), with high rates of permanent procedural success with a single attempt. However, there are still instances of acute procedural failure and AP recurrences with standard RF and cryotherapy methods.

METHODS

Seven consecutive cases of pre-excitation syndromes with prior failed RF catheter ablation had the novel treatment. Cryotherapy was delivered using two 8 mm tip focal cryoablation catheters (Freezor® Max, Medtronic, Minneapolis, Minnesota, USA).

RESULTS

Accessory pathway localisation was septal in 5 cases, left posterolateral in 1, right lateral in 1. In all cases, ablation of the AP was acutely successful with no procedural complications. Median procedure and fluoroscopy durations were 199 and 35 min, sequentially. Median Procedure duration fell significantly in the second half of series (174 min) compared to the first half (233 min, P = 0.05). One patient had evidence of a recurring AP conduction with pre-excitation at 5-week follow up. After a median follow up of 66.8+-6.5 months, 6 out of 7 patients remained asymptomatic and free of pre-excitation.

CONCLUSION

Simultaneous multi-catheter cryotherapy is feasible, safe and can provide definitive cure of accessory pathways that were previously resistant to standard radiofrequency ablation. Further study is required in the assessment of this novel form of advanced cryotherapy to treat complex and resistant arrhythmias.

Randomized comparison of oesophageal protection with a temperature control device: results of the IMPACT study

Aims 

Thermal injury to the oesophagus is an important cause of life-threatening complication after ablation for atrial fibrillation (AF). Thermal protection of the oesophageal lumen by infusing cold liquid reduces thermal injury to a limited extent. We tested the ability of a more powerful method of oesophageal temperature control to reduce the incidence of thermal injury.

Methods and results 

A single-centre, prospective, double-blinded randomized trial was used to investigate the ability of the ensoETM device to protect the oesophagus from thermal injury. This device was compared in a 1:1 randomization with a control group of standard practice utilizing a single-point temperature probe. In the protected group, the device maintained the luminal temperature at 4°C during radiofrequency (RF) ablation for AF under general anaesthesia. Endoscopic examination was performed at 7 days post-ablation and oesophageal injury was scored. The patient and the endoscopist were blinded to the randomization. We recruited 188 patients, of whom 120 underwent endoscopy. Thermal injury to the mucosa was significantly more common in the control group than in those receiving oesophageal protection (12/60 vs. 2/60; P = 0.008), with a trend toward reduction in gastroparesis (6/60 vs. 2/60, P = 0.27). There was no difference between groups in the duration of RF or in the force applied (P value range= 0.2–0.9). Procedure duration and fluoroscopy duration were similar (P = 0.97, P = 0.91, respectively).

Conclusion 

Thermal protection of the oesophagus significantly reduces ablation-related thermal injury compared with standard care. This method of oesophageal protection is safe and does not compromise the efficacy or efficiency of the ablation procedure.

Multi-catheter cryotherapy compared with radiofrequency ablation in long-standing persistent atrial fibrillation: a randomized clinical trial

AIMS

Restoring sinus rhythm (SR) by ablation alone is an endpoint used in radiofrequency (RF) ablation for long-standing persistent atrial fibrillation (AF) but not with cryotherapy. The simultaneous use of two cryotherapy catheters can improve ablation efficiency; we compared this with RF ablation in chronic persistent AF aiming for termination to SR by ablation alone.

METHODS AND RESULTS

Consecutive patients undergoing their first ablation for persistent AF of >6 months duration were screened. A total of 100 participants were randomized 1:1 to multi-catheter cryotherapy or RF. For cryotherapy, a 28-mm Arctic Front Advance was used in tandem with focal cryoablation catheters. Open-irrigated, non-force sensing catheters were used in the RF group with a 3D mapping system. Pulmonary vein (PV) isolation and non-PV triggers were targeted. Participants were followed up at 6 and 12 months, then yearly. Acute PVI was achieved in all cases. More patients in the multi-catheter cryotherapy group were restored to SR by ablation alone, with a shorter procedure duration. Sinus rhythm continued to the last available follow-up in 16/49 patients (33%) in the multi-catheter at 3.0 ± 1.6 years post-ablation and in 12/50 patients (24%) in the RF group at 4.0 ± 1.2 years post-ablation. The yearly rate of arrhythmia recurrence was similar.

CONCLUSION

Multi-catheter cryotherapy can restore SR by ablation alone in more cases and more quickly than RF ablation. Long-term success is difficult to achieve by either methods and is similar with both.

A registry review of 2532 catheter ablations for atrial fibrillation using active thermal protection

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Dr Leung has received research support from Attune Medical (Chicago, IL). Dr Gallagher has received research funding from Attune Medical (Chicago, IL).

Background

  Thermal injury to the oesophagus causes a spectrum of adverse effects after ablation for atrial fibrillation (AF); at the most severe end, atrio-oesophageal fistula carries a high mortality rate. Controlled active thermal protection in the oesophagus during ablation is the most promising method of oesophageal protection. Randomized evidence from the IMPACT trial (NCT03819946) showed an 83.4% reduction in endoscopically detected oesophageal lesions compared to standard care when an oesophageal temperature control device was used to control the local temperature. The IMPACT patients who were randomized to the use of the device had no adverse event related to its use.  Real world registry data on applications of this device have not previously been available. 

Purpose

To determine the safety of an oesophageal temperature control device by review of real-world registry data on its clinical use and any reported device-related adverse events.

Methods

  We reviewed the following databases for any reported oesophageal temperature control device-related complications: The United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE), FDA Medical and Radiation Emitting Device Recalls, the Medicines and Healthcare products Regulatory Agency (MHRA) Medical Device Alerts and SwissMedic records of Field Safety Corrective Actions (FSCA). An internal registry (post-marketing follow up) database maintained by the manufacturer of the device was used to quantify the number used for each indication.  Reported events were reviewed and catalogued for description and identification of any events related to its use in the cardiac electrophysiology lab. The IMPACT study patients were reviewed for any device-related events.

Results

  Of the 13, 284 oesophageal temperature control devices used, 2532 were recorded as having been used for the purpose of oesophageal protection during catheter ablation for AF.  A total of 5 events associated with the device were identified, all from the MAUDE database.  Three were from 2017, one from 2018, and one from 2019.  All involved its use in critical care or trauma patients and were related to user error or contraindicated patient selection; none resulted in serious harm to the patient. No adverse events occurred related to its use in the cardiac electrophysiology lab. No case of clinically significant oesophageal injury was reported in a patient who had been protected by the oesophageal temperature control device.

Conclusions

Real world registry data has shown no adverse events reported to date in over 2500 uses of an oesophageal temperature control device in the cardiac electrophysiology lab, for the purpose of active thermal protection. This data supports the randomized trial evidence of its clinical effectiveness. Abstract Figure. Oesophageal active thermal protection

Patient outcomes after AF ablation using Ablation Index technology with oesophageal protection: insight from the IMPACT study

Background

Atrio-oesophageal fistula formation accounts for the majority of AF ablation-related morbidity and mortality. Thermal injury to the oesophagus can be significantly reduced by application of oesophageal cooling for protection during AF ablation. The effect of this method of oesophageal protection in patients receiving radiofrequency (RF) ablation guided by Ablation Index technology is currently unknown.

Objective

To investigate the ability of a temperature control device to protect the oesophagus from ablation-related thermal injury in patients receiving AF ablation guided by Ablation Index technology.

Methods

The IMPACT study is a single-centre, prospective, double-blind randomized controlled trial, which investigated the ability of a controlled method of oesophageal cooling to protect the oesophagus from ablation-related thermal injury. The EnsoETM device was used to deliver oesophageal cooling. This method was compared in a 1:1 randomization to a control group of standard practice utilizing a single-sensor temperature probe. In the study group, the device was used to keep the luminal temperature at 4°C during RF ablation. All participants received AF ablation using Ablation Index technology at posterior and anterior settings (30W at 350–400 and 40W at 450–500, respectively). Endoscopic examination was performed within 7 days post-ablation and oesophageal injury was graded. The patient and the endoscopist were blinded to the randomization. Structured clinical follow up occurred after 3 months post-ablation; both patient and follow up clinician were blinded.

Results

We recruited 188 patients, of whom 120 underwent endoscopic evaluation. Thermal injury to the mucosa was significantly more common in the control group than in those receiving oesophageal protection (12/60 versus 2/60; P=0.008). There was no difference between groups in RF time, lesion duration, force, power and combined ablation index (P value range= 0.2–0.9). Procedure and fluoroscopy duration were similar (P=0.97, P=0.91 respectively). The majority of those who passed through the 1st follow up evaluation (n=136) did not have gastrointestinal or chest pain symptoms post ablation and there was no difference between the randomized groups. Only 4.4% overall had severe symptoms and they were poorly correlated against those who sustained mucosal lesions. AF recurrence was similar in both groups (8% vs 8.8%). There were 2 cases of vascular trauma needing intervention in the control group and 1 case of conservatively managed pericardial effusion in the protected group only. Clinical and endoscopy findings did not report any EnsoETM device-related trauma.

Conclusion

Thermal protection of the oesophagus significantly reduces ablation-related thermal injury compared to standard care when ablation is performed using radiofrequency with Ablation Index technology. This method of oesophageal protection is safe and does not compromise the efficacy of the ablation procedure.

Endoscopy findings and patient symptoms.

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): 1. Public hospital: St. George's NHS Foundation Trust; 2. Private company: Attune Medical (Chicago, IL)

P1862Phrenic nerve damage after atrial fibrillation ablation using second generation cryoballoon

Background

Cryoballoon (CB) ablation is a safe alternative to radiofrequency ablation in the treatment of atrial fibrillation (AF). However, phrenic nerve damage (PND) is a bothersome complication of the procedure.

Purpose

In this study, we aimed to establish the incidence of PND during CB and define the characteristics of affected patients.

Methods

In this retrospective analysis, all patients with AF that underwent CB ablation between 2013 and 2018 were included into the study. Characteristics and outcomes of patients complicated with PND were evaluated. PND was detected by palpation of diaphragma contractions or observation of reduced diaphragma motility by fluoroscopy during the procedure.

Results

Totally 653 patients were included in the study. PND was detected in 3.5% (23/653) of the patients. Median age of the patients with PNP was 56 (25–78) years and 10 patients (43.4%) were male. The most common ablation site related with PND was right superior pulmonary vein (RSPV) (18 patients, 78%). Transient PND was observed in 16 patients (69%) of the patients which resolved within 24 hours after the procedure. In the remaining 5 patients (21%) diaphragmatic contraction was recovered at the 6th month control visit. In 2 patients (10%), phrenic nerve paralysis was still present >1 year visit.

Table 1. Baseline characteristics of patients with PND Age (years), median (min–max) 56 (25–78) Gender, n (male %) 10 (43.4%) Hypertension, n (%) 9 (39.1%) LA (mm), (mean ± sd) 38.5±5.8 EF (%), (mean ± sd) 60.8±6.5 Structrual heart disease, n (%) 3 (0.13%) – HCMP 2 (0.087%) – DCMP 1 (0.043%) DCMP: Dilated cardiomyopathy; HCMP: Hypertrophic cardiomyopathy; EF: Ejection fraction; LA: Left atrium; PND: Phrenic nerve damage.

Conclusion

PND is not a rare complication of CB ablation despite all the preventive maneuvers during the procedure and technological developments. However, most of the PND recovered during the follow-up.

P1920Long-term outcomes of pulmonary vein isolation using second-generation cryoballoon during atrial fibrillation ablation: A single-center large-scale study

Background

Currently available second-generation cryoballoon (CB2) is accepted as an effective and safe tool for pulmonary vein isolation (PVI). Although much more data exists about 1-year outcomes of CB2 ablation, data on long-term outcomes are scarce. Objective: We aimed to assess the long-term outcomes of PVI using CB2 in a large-scale symptomatic AF population at our tertiary referral center.

Methods

In this non-randomized prospective observational study, a total of 486 patients with paroxysmal (71%) or persistent (29%) AF who underwent index PVI using CB2 at our hospital between January 2013 and June 2017 were enrolled. Atrial tachyarrhythmia (ATa) free survival was defined as absence of AF, atrial flutter or atrial tachycardia recurrence >30 s following 3-months blanking period. Predictors of recurrence were evaluated by univariate and multivariate Cox proportional hazards regression models.

Results

Acute procedural success rate was 99.8% (1898/1902 PVs). Mean procedural and fluoroscopy time were 64.9±9.2 and 12.1±2.6, respectively. At median 39 (IQR: 26–56) months follow-up, ATa free survival was 78.6% after a single procedure (280/345 [81.2%] for paroxysmal AF vs 102/141 [72.3%] for persistent AF, p=0.019) and 84.4% after a mean 1.48±0.42 ablations.Cox regression analysis showed that left atrium diameter, duration of AF history and early ATa recurrence were found as the independent predictors of late recurrence. PNP was observed in 17 (3.5%) patients.

Figure 1

Conclusions

Second-generation CB based PVI is effective to maintain sinus rhythm in a significant proportion of paroxysmal and early persistent AF patients with an acceptable complication rates at long-term follow-up.

Long-term outcomes of pulmonary vein isolation using second-generation cryoballoon during atrial fibrillation ablation

BACKGROUND

Currently available second-generation cryoballoon (CB2) is accepted as an effective and safe tool for pulmonary vein isolation (PVI). Although much more data exist about 1-year outcomes of CB2 ablation, data on long-term outcomes are scarce.

OBJECTIVE

We aimed to assess the long-term outcomes of PVI using CB2 in a large-scale symptomatic atrial fibrillation (AF) population at our tertiary referral center.

METHODS

In this nonrandomized prospective observational study, a total of 486 patients with paroxysmal (71%) or persistent (29%) AF who underwent index PVI using CB2 at our hospital between January 2013 and June 2017 were enrolled. Atrial tachyarrhythmia (ATa)-free survival was defined as the absence of AF, atrial flutter, or atrial tachycardia recurrence ≥30 s following a 3 months blanking period. Predictors of recurrence were evaluated by univariate and multivariate Cox proportional hazards regression models.

RESULTS

Acute procedural success rate was 99.8% (1898/1902 PVs). Mean procedural and fluoroscopy time were 64.9 ± 9.2 and 12.1 ± 2.6, respectively. At median 39 (interquartile range: 26-56) months follow-up, ATa-free survival was 78.6% after a single procedure (280/345 [81.2%] for paroxysmal AF vs. 102/141 [72.3%] for persistent AF, P = .019) and 84.4% after a mean 1.48 ± 0.42 ablations. Cox regression analysis showed that left atrium diameter, duration of AF history, and early ATa recurrence were found as the independent predictors of late recurrence. Phrenic nerve palsy was observed in 17 (3.5%) patients.

CONCLUSIONS

CB2-based PVI is effective to maintain sinus rhythm in a significant proportion of paroxysmal and persistent AF patients with an acceptable complication rate at long-term follow-up.

Half a century of continuous pacing: a living witness to the evolution of a technology

To chart the development of pacing technology and its pitfalls we present the experience of a patient who has benefitted from it but also suffered as a result of it from its earliest days. A 53-year-old physician was referred to us with obstruction of the superior and inferior vena cava on a background of more than 50 years of continuous ventricular pacing and 24 previous pacemaker-related interventions. In a single surgical procedure, his existing pacing system and redundant leads were extracted, the superior vena cava was reconstructed, and a new biventricular pacing system with epicardial leads was implanted. Pacemakers can maintain life and preserve the quality of life for many decades. The quality of this therapy has improved due to advances in the technology and in techniques. Maintaining safe pacing in the very long term requires labour, patience, and ingenuity.

Remanufactured circular mapping catheters: safety, effectiveness and cost

Background

The use of remanufactured single-use devices (SUDs), including cardiac electrophysiology catheters, has become established in the USA and other health care systems but without much published scientific evaluation on the relative safety or efficacy of these devices. In the United Kingdom (UK), the use of remanufactured SUDs has not been routine. We performed a structured evaluation of the safety and efficacy of a remanufactured circular mapping catheter (Stryker® remanufactured Lasso NAV 2515) during its introduction in our centre.

Methods

We prospectively evaluated the performance of a remanufactured circular mapping catheter in 100 consecutive patients undergoing an AF ablation. Operator feedback was obtained, assessing the device appearance, ease of use and function. As an indirect measurement of efficacy, acute procedure metrics were compared to those in 100 propensity-matched cases performed by the same operators using a new device. Cost savings were calculated.

Results

No complication occurred in association with the remanufactured device. There was one reported failure of device malfunction—the flexion-extension mechanism of a remanufactured catheter and none in the matched-control group. There was satisfactory communication with the electro-anatomic mapping system. Ease of use of the remanufactured catheter was reported to be similar to a newly manufactured device. Procedural duration was similar with remanufactured devices and matched controls. With 100 cases using the remanufactured device, cost savings amounted to £30,444.

Conclusions

The use of remanufactured circular mapping catheters is safe, efficient and reliable. Widespread use of remanufactured SUDs offers the possibility of significant economic benefit.

Left ventricular lead misplacement discovered a decade after cardiac resynchronization therapy-defibrillator implantation: a case report

Introduction

Satisfactory left ventricular (LV) lead placement into the coronary sinus (CS) can be achieved in the majority of patients but there are still instances of acute failure most often due to anatomical differences, for example due to tortuous CS anatomy. Chronic LV lead misplacement and its delayed discovery is not a common scenario. It is unclear if chronic dual right ventricular pacing can hasten the progression of heart failure.

Case presentation

A 73-year-old lady presented to our cardiac centre with severe heart failure. She had non-ischaemic dilated cardiomyopathy with underlying left bundle branch block and a cardiac resynchronization therapy-defibrillator device in situ for the past decade. She also had a chronic pericardial effusion of unknown aetiology. Whilst the patient was being treated for acute heart failure, it was noted on patient telemetry that the QRS morphology for supposed bi-ventricular pacing was unusual. This led to a lateral chest radiograph and a CS venogram to be performed, both of which confirmed that the LV lead was in fact not in the CS. Plans were made to place a new LV lead but unfortunately the patient continued to clinically deteriorate despite maximal treatment and died before this could be performed.

Discussion

It is only with thorough review of the electrocardiographic data and chest radiography that led to the discovery of chronic LV lead misplacement. This case illustrates the importance of expert review of radiographic imaging and electrocardiographic data in patients with implanted cardiac devices.

Demographics, treatment and outcomes of atrial fibrillation in a developing country: the population-based TuRkish Atrial Fibrillation (TRAF) cohort

Aims

Although atrial fibrillation (AF) is increasingly common in developed countries, there is limited information regarding its demographics, co-morbidities, treatments and outcomes in the developing countries. We present the profile of the TuRkish Atrial Fibrillation (TRAF) cohort which provides real-life data about prevalence, incidence, co-morbidities, treatment, healthcare utilization and outcomes associated with AF.

Methods and results

The TRAF cohort was extracted from MEDULA, a health insurance database linking hospitals, general practitioners, pharmacies and outpatient clinics for almost 100% of the inhabitants of the country. The cohort includes 507 136 individuals with AF between 2008 and 2012 aged >18 years who survived the first 30 days following diagnosis. Of 507 136 subjects, there were 423 109 (83.4%) with non-valvular AF and 84 027 (16.6%) with valvular AF. The prevalence was 0.80% in non-valvular AF and 0.28% in valvular AF; in 2012 the incidence of non-valvular AF (0.17%) was higher than valvular AF (0.04%). All-cause mortality was 19.19% (97 368) and 11.47% (58 161) at 1-year after diagnosis of AF. There were 35 707 (7.04%) ischaemic stroke/TIA/thromboembolism at baseline and 34 871 (6.87%) during follow-up; 11 472 (2.26%) major haemorrhages at baseline and 10 183 (2.01%) during follow-up, and 44 116 (8.69%) hospitalizations during the follow-up.

Conclusion

The TRAF cohort is the first population-based, whole-country cohort of AF epidemiology, quality of care and outcomes. It provides a unique opportunity to study the patterns, causes and impact of treatments on the incidence and outcomes of AF in a developing country.

Left atrial appendage isolation in addition to pulmonary vein isolation in persistent atrial fibrillation: one-year clinical outcome after cryoballoon-based ablation

Aims

In this study, we sought to evaluate the safety and efficacy of cryoballoon (CB) based empirical left atrial appendage (LAA) isolation as an adjunct to pulmonary vein isolation (PVI) compared to the PVI-only strategy in patients with persistent AF.

Objectives

Clinical outcomes of catheter ablation were less beneficial for persistent atrial fibrillation (AF) than paroxysmal AF.

Methods and results

A total of 100 consecutive patients with persistent AF underwent both PVI and additional LAA isolation using CB (Group II). As a control group (Group I), among persistent AF patients, we conducted a retrospective, propensity-score matched cohort, in whom only PVI was performed using CB. Recurrence of atrial tachyarrhythmia (Ata) at the 12th month follow-up was the primary endpoint. Baseline demographic and clinical characteristics were similar between two groups. At the 12th month follow-up, 67 (67%) patients in Group I and 86 (86%) patients in Group II were free of ATa after the index procedure (P < 0.001). As a unique complication of LAA isolation, left circumflex artery spasm was observed in 4% of the Group II. After adjusting for several baseline variables, PVI-only strategy was found as a significant predictor for recurrence (HR: 3.37; 95% CI: 1.73-6.56; P < 0.001). Transoesophageal echocardiography examination during the follow-up revealed no thrombus in the LAA.

Conclusion

Our findings indicated that LAA isolation as an adjunct to PVI improved 1-year outcomes in persistent AF compared with the PVI-only strategy using CB without an increase in thromboembolic complications.

Echocardiographic assessment of regional right ventricular systolic function using two-dimensional strain echocardiography and evaluation of the predictive ability of longitudinal 2D-strain imaging for pulmonary arterial hypertension in systemic sclerosis patients

Systemic sclerosis (SSc) is a generalized connective tissue disorder, and SSc patients are at risk of developing pulmonary arterial hypertension (PAH). The aims of this study are to evaluate the right ventricular regional systolic function using two-dimensional speckle-tracking echocardiography (2D STE) and to determine the predictive ability of peak longitudinal systolic strain (PLSS) at the RV lateral wall for PAH in SSc patients. 80 SSc patients (mean age 51 ± 12 years) were included in the study. Echocardiography and 2D STE were performed at baseline and after 12 months. RHC was performed only in SSc patients with clinical indications. PLSS at the apical segment of the RV free wall was significantly impaired in PAH patients compared with non-PH patients (-14.6 ± 5.9 vs. - 22.2 ± 7.5%, p = 0.034). PLSS at the basal, mid, and apical segments of the RV free wall was lower in both groups at follow-up compared to baseline, but the drop in strain values was statistically significant only in the non-PH group (p < 0.05). Right atrial area (OR 1.758; p = 0.023), peak tricuspid regurgitation velocity (OR 24.23; p = 0.011) and PLSS at the apical segment of the RV lateral wall (OR 2.47; p = 0.005) were independent predictors of PAH. A cut-off value of - 14.48% PLSS at the apical segment of the RV lateral wall resulted in 100% specificity for predicting PAH in SSc patients. RV pressure overload affects RV systolic function as manifested by impaired RV longitudinal deformation. Evaluating RV regional systolic function with 2D STE could be useful as an additional echocardiographic parameter for screening PAH in SSc patients.

Entrapment of focal atrial tachycardia using cryoballoon ablation; Sinus rhythm in the left atrium and ongoing atrial tachycardia in the left atrial appendage

Left atrial appendage (LAA) is a well-known source of focal atrial tachycardias (AT). Although radio-frequency (RF) energy is the most commonly used technique in such cases, there was an option other than epicardial approach when RF technique fails. Cryoballoon technology is primarily developed to be used for pulmonary vein isolation (PVI). Also, there was no report regarding the isolation of LAA by using cryo-balloon in patients with focal AT. In this case, for the first time in the literature, we successfully isolated the LAA because of failed attempts of RF ablation for focal AT in whom the surface electrogram showed a sinus rhythm while arrhythmia continues inside the LAA.

Exercise heart rate recovery assessment of the cardiac autonomic nervous system in workers occupationally exposed to lead

OBJECTIVE

The aim of the present study was to assess cardiac autonomic function via indices of exercise heart rate recovery (HRR) in workers occupationally exposed to lead.

METHODS

A total of 98 lead-exposed workers and 98 healthy controls were enrolled. All underwent exercise testing and transthoracic echocardiography. HRR indices were calculated by subtracting 1st- (HRR1), 2nd- (HRR2), and 3rd-minute (HRR3) heart rates from maximal heart rate (HR). Exercise test parameters- HRR in particular- were compared between groups, and correlation analysis of blood, 24-hour urine lead levels, and test parameters was performed.

RESULTS

Baseline demographic and clinical characteristics were found to be similar between groups. Mean HRR1 (26.2±3.6 vs 29.0±4.1 bpm, p<0.001), HRR2 (42.6±3.9 vs 46.9±3.7 bpm, p<0.001), and HRR3 (56.6±4.5 vs 61.8±4.3 bpm, p<0.001) values were significantly lower in the lead-exposed group than in the healthy controls. HRR1 was found to be significantly correlated with blood (r:-0.415; p<0.001) and 24-hour urine lead levels (r:-0.446; p<0.001). HRR2 and HRR3 were significantly correlated with 24-hour urine lead level (r:-0.396; p<0.001 and r:-0.233; p=0.021, respectively).

CONCLUSION

Lead-exposed workers had lower HRR indices than normal subjects. Blood and 24-hour urine lead levels were significantly associated with HRR indices. Cardiac autonomic functions may be affected by exposure to lead, and those occupationally exposed should be closely followed for adverse cardiovascular outcome.

Serum galectin-3 level as a marker of thrombogenicity in atrial fibrillation

BACKGROUND

Left atrial appendage flow velocity (LAAFV) and presence of spontaneous echo contrast (SEC) have been reported to be predictors of thromboembolism in atrial fibrillation (AF) patients. Galectin-3 is a biomarker reflecting pro-inflammatory status, whose role in AF has recently drawn attention, particularly in persistent AF population.

AIM

In this study we aimed to investigate the association between serum galectin-3 levels and echocardiographic predictors of thromboembolism in persistent AF patients.

METHODS

We included 65 persistent AF patients (55.50±10.67 years, 46.15% male). Transesophageal echocardiography (TEE) was performed to assess LAAFV and presence of left atrial (LA)/LA appendage (LAA)-located SEC and thrombus prior to direct current cardioversion or catheter ablation for AF.

RESULTS

Median galectin-3 level was 0.63 ng/mL. Serum galectin-3 levels were significantly correlated with LAAFV (r=-.440, P<.001). Serum galectin-3 levels were associated with presence of SEC (P<.001), and LA thrombus (P=.008). Receiver operating characteristic analysis revealed that a serum galectin-3 greater or equal to the cut-off value of 0.69 predicted presence of SEC with a sensitivity and specificity of 91.00% and 79.00%, respectively (P<.001).

CONCLUSION

In conclusion, in the setting of persistent AF, serum galectin-3 levels are associated with presence of SEC and LAAFV on TEE. Our findings suggest that serum galectin-3 level may have a place in thromboembolism risk stratification in persistent AF patients.

Pulmonary vein anatomy and its variations in a Turkish atrial fibrillation cohort undergoing cryoballoon-based catheter ablation

OBJECTIVE

Pulmonary vein (PV) anatomy has drawn attention since assumption that atrial fibrillation (AF) may originate from PVs and that electrical isolation of PVs may be beneficial in eliminating these triggers. The present study aims to investigate PV anatomy and its variations in a sample of Turkish patients undergoing PV isolation (PVI) for AF.

METHODS

250 patients underwent multidetector computed tomography before cryoballoon-based PVI for AF. PV and left atrial (LA) anatomy were evaluated in 3-dimensional epicardial reconstructions.

RESULTS

980 PVs were observed. All PVs drained into the LA. Mean superoinferior (SI) dimension for each vein was significantly larger than mean anteroposterior (AP) dimension. Accessory PVs were only seen on right side. Accessory veins were significantly smaller in both AP and SI diameter than other veins. Right-sided PV ostia were more round. Expected anatomy of 2 atrial ostia for right upper and lower lobe veins on each side was seen in 94.8% of patients. Remainder had other variant anatomy in right PVs. Conjoined ostium in the LA was seen in 35.6% of patients.

CONCLUSION

PV variations were common in Turkish AF cohort undergoing PVI, which may be important to know about prior to ablation therapy for procedural success.

Role of Adjuvant Renal Sympathetic Denervation in the Treatment of Ventricular Arrhythmias

Ventricular arrhythmias (VAs) are known to result in significant morbidity and mortality rates in patients with both ischemic and nonischemic dilated cardiomyopathy. Although catheter ablation has emerged as an adjunct treatment strategy in the management of VAs, 1-year follow-up data have revealed that ventricular tachycardia (VT)-free survival rate is ∼50%. Up to now, a few small case series with short-term follow-up have reported reduced VT recurrence after application of renal sympathetic denervation (RSDN) in patients with refractory VAs. In this study, we aimed to investigate the safety and efficacy of RSDN as an adjunctive therapy to catheter ablation for refractory VAs in patients with dilated cardiomyopathy. For this purpose, we conducted a retrospective, propensity score-matched cohort study. A total of 32 patients with implantable cardioverter-defibrillators (ICDs) who underwent catheter ablation or both catheter ablation and RSDN for refractory VAs were included in the analysis. Patients were followed up at a median of 15 months (6 to 20 months). Patient groups did not differ regarding the mean number of VT/ventricular fibrillation episodes in the last 6 months before the procedure (35.00 ± 4.10 in catheter ablation-only group vs 43.00 ± 5.30 in catheter ablation + RSDN group, p = 0.23). There was a significant decrease in burden of both VT/ventricular fibrillation and antitachycardia pacing and shock therapies delivered from ICDs in the patient group that received RSDN as an adjunct therapy (p <0.05). Mortality rates were similar in 2 groups (p >0.05). In conclusion, our findings suggest that adjunctive RSDN is a safe and effective method for reducing the arrhythmic burden in patients with refractory VAs. In the future, it may be performed routinely in patients with ICDs and refractory VAs.

Bethesda classification is a valuable guide for fine needle aspiration reports and highly predictive especially for diagnosing aggressive variants of papillary thyroid carcinoma

BACKGROUND

A fine needle aspiration biopsy (FNAB) is the most valuable diagnostic procedure for pre-operative discrimination of benign and malignant nodules. The Bethesda System for Reporting Thyroid Cytopathology provides standardised reporting and cytomorphological criteria in aspiration smears. The aim of the present study was to determine malignancy rates in nodules with different cytology results and evaluate the diagnostic value of Bethesda for variants of papillary thyroid carcinoma (PTC).

MATERIALS AND METHODS

A retrospective analysis of 2534 cases with 5784 thyroid nodules, who underwent FNAB followed by surgery, were included in this study. FNAB was performed with ultrasonography guidance. Cytological diagnoses were classified as: non-diagnostic (ND), benign, atypia of undetermined significance/follicular lesions of undetermined significance (AUS/FLUS), follicular neoplasm/suspicious for follicular neoplasm (FN/SFN), suspicious for malignancy (SUS) and malignant. Histopathological diagnoses were classified into four groups: benign, PTC, follicular thyroid cancer and other types of thyroid cancer (including medullary thyroid cancer, undifferentiated thyroid cancer and thyroid tumours of uncertain malignant potential). Cases with PTC were further divided into four categories: conventional variant, follicular variant, aggressive variants (tall cell, diffuse sclerosing and columnar variant) and other variants (oncocytic, solid/trabecular and warthin-like variants). FNAB results were compared with histopathological results.

RESULTS

Malignancy rates were 6.3%, 3.2%, 20.7%, 33.3%, 74.2% and 95.6% in the nodules with ND, benign, AUS/FLUS, FN/SFN, SUS and malignant cytology results, respectively. Pre-operative cytology was malignant or SUS in 56.6% of conventional, 24.3% of follicular, 92% of aggressive and 41.7% of other variants of histopathologically confirmed PTC. The difference between the groups was significant (P < 0.001).

CONCLUSION

The Bethesda classification is a reliable indicator of malignancy in nodules with different cytology results and seems to be very effective in predicting the malignancy for the nodules diagnosed with aggressive variant PTC on the final histological examination.

Transcatheter aortic valve implantation in patients with a mitral prosthesis; single center experience and review of literature

OBJECTIVES

Following the encouraging results of several registries and trials, transcatheter aortic valve implantation (TAVI) has been recognized as a valid option in patients with severe aortic stenosis deemed at high or prohibitive risk for surgical treatment. Good procedural success and good clinical outcomes have been showed and very limited data exist on TAVI in the setting of a preexisting mitral prosthesis regarding the technique, potential complications, and outcomes.

METHODS

Here, we report six cases of transfemoral TAVI with a self-expanding bioprosthesis (CoreValve; Medtronic, Inc) in patients who had previously undergone mitral valve replacement. Preprocedural, intraprocedural ve postprocedural outcome and data were analyzed and a brief literature review is also presented.

RESULTS AND CONCLUSION

Our experiences show that transfemoral CoreValve implantation can be performed successfully in patients with mechanical and bioprosthetic mitral valves.

Initial experience with the TightRail™ Rotating Mechanical Dilator Sheath for transvenous lead extraction

AIMS

In parallel with increasing implantation rates and patients' longer life expectancy, the need for transvenous lead extraction (TLE) as a specialized procedure has shown a significant growth over years. Herein, we aimed to present our initial experience in TLE by using a novel TightRail™ Rotating Mechanical Dilator Sheath.

METHODS AND RESULTS

Between October 2014 and March 2015, a total of 42 leads in 23 patients were removed at our tertiary referral centre. All of the extracted leads were >12 months old and indications for extraction were based on the recommendations of the Heart Rhythm Society. The leads were removed by using the TightRail™ Mechanical Dilator Sheath (Spectranetics Corporation) with the rotational cutting force only. Indications for lead removal included cardiac device infection in 12 (52.2%) cases, lead malfunction in the 10 (43.5%) cases, and upgrade to cardiac resynchronization therapy-defibrillator (CRT-D) in the remaining 1 case (4.3%). The extracted devices were pacemaker in 10 (43.4%) cases, implantable cardioverter-defibrillator (ICD) in 7 (30.4%) cases, and CRT in the remaining 6 (26.0%) subjects. Among 42 leads, 10 (23.8%) were right ventricular, 14 (33.3%) were atrial, 13 (31.0%) were defibrilator, and 5 (11.9%) were coronary sinus electrodes. The median time from implantation was 72 (18-216) months. Complete procedural success with TightRail™ system alone was achieved in 22 (95.7%) patients (41/42 leads) and overall clinical success was 100%. One right ventricular lead was completely removed with the help of femoral snare. All the patients were discharged uneventfully without any complication.

CONCLUSION

Our preliminary data with small sample size show that TightRail™ Mechanical Dilator Sheath is a new useful tool for chronically implanted pacemaker (PM)/ICD leads. Continued investigation including large patient cohort is required to evaluate success and complication rates in comparison to other tools and techniques.

Periatrial epicardial adipose tissue thickness is an independent predictor of atrial fibrillation recurrence after cryoballoon-based pulmonary vein isolation

BACKGROUND

Epicardial adipose tissue (EAT) is a metabolically active fat depot. Studies have investigated the effect of EAT thickness on outcomes of radiofrequency catheter ablation of atrial fibrillation (AF). However, data on the relationship between EAT thickness and outcome of cryoballoon-based pulmonary vein isolation (PVI) are lacking.

OBJECTIVE

In this study, we investigate the association between EAT thickness and AF recurrence after cryoballoon-based PVI.

METHODS

Patients with symptomatic paroxysmal or persistent AF despite ≥1 antiarrhythmic drug(s) were scheduled for cryoballoon-based PVI for AF per the recent recommendations. Periatrial, periventricular, and total EAT thickness measurements were obtained from preprocedural multidetector CT scans.

RESULTS

A total of 249 patients (55.6 ± 10.7 years; 48.2% male; 18.5% persistent AF) were involved in the study. Patients were followed-up for 29 months (8-48 months). When blanking period was considered, freedom from AF after the ablation procedure was 75.9% at a median follow-up of 29 months. Total periatrial EAT thickness (18.1 ± 6.2 vs. 14.7 ± 4.7 mm; P < .001) was greater in patients with late AF recurrence when compared to those without. On the other hand, periventricular or total EAT thickness measurements did not differ between both groups (P > .05). Multivariate Cox proportional hazard regression analysis showed that periatrial EAT thickness (hazard ratio, 1.086; P = .001) and left atrial volume index (hazard ratio, 1.144; P < .001) were independent predictors for late AF recurrence.

CONCLUSION

Quantification of EAT thickness from preprocedural multidetector CT scans may serve as a beneficial parameter for prediction of AF recurrence after cryoballoon-based PVI.

The Association of Serum Galectin-3 Levels with Atrial Electrical and Structural Remodeling

INTRODUCTION

Left atrial (LA) interstitial fibrosis is known to have a role in the initiation and maintenance of atrial fibrillation (AF). The role of galectin-3 in the pathogenesis of cardiac fibrosis has been demonstrated in previous studies. We aimed to determine whether serum galectin-3 level is associated with markers of atrial remodeling, including the extent of LA fibrosis detected by delayed enhancement magnetic resonance imaging (DE-MRI) and atrial electromechanical delay (AEMD) in paroxysmal AF patients with preserved left ventricular (LV) functions.

METHODS AND RESULTS

Thirty-three patients (58 [28-74] years, 51.5% male) with paroxysmal AF who underwent DE-MRI prior to cryoballoon-based AF ablation were included in the study. Serum galectin-3 levels were measured with ELISA. LA volume index (B ± SE: 0.424 ± 0.504, 95% CI: 0.560-2.627, P = 0.004) and serum galectin-3 levels (B ± SE: 0.549 ± 7.745, 95% CI: 16.874-47.550, P < 0.001) were found to be independently correlated with extent of LA fibrosis detected with DE-MRI in paroxysmal AF patients with preserved LV function. Correlation analysis between AEMD parameters and baseline characteristics showed that galectin-3 was significantly correlated with intra-left (ρ = 0.432, P = 0.012) and inter-AEMD (ρ = 0.395, P = 0.023). Duration of AF, LAD, and extent of LA fibrosis were also found to be significantly correlated with AEMD parameters.

CONCLUSION

This is a hypothesis-generating study pointing out that serum galectin-3 level is significantly associated with atrial remodeling in paroxysmal AF patients with preserved LV function. Further studies are necessary to provide exact pathophysiological mechanisms.