Artificial Intelligence-Based Clinical Decision Support Systems in Cardiovascular Diseases

Despite all the advancements in science, medical knowledge, healthcare, and the healthcare industry, cardiovascular disease (CVD) remains the leading cause of morbidity and mortality worldwide. The main reasons are the inadequacy of preventive health services and delays in diagnosis due to the increasing population, the failure of physicians to apply guide-based treatments, the lack of continuous patient follow-up, and the low compliance of patients with doctors' recommendations. Artificial intelligence (AI)-based clinical decision support systems (CDSSs) are systems that support complex decision-making processes by using AI techniques such as data analysis, foresight, and optimization. Artificial intelligence-based CDSSs play an important role in patient care by providing more accurate and personalized information to healthcare professionals in risk assessment, diagnosis, treatment optimization, and monitoring and early warning of CVD. These are just some examples, and the use of AI for CVD decision support systems is rapidly evolving. However, for these systems to be fully reliable and effective, they need to be trained with accurate data and carefully evaluated by medical professionals.

Perspectives on the Use of Digital Health Technologies in Cardiology Among Specialists from an ESC Member Country: Results from a Survey

OBJECTIVE

In this study, we aimed to identify the reasons for and perceived challenges associated with the use of digital health technologies (DHT) in cardiology.

METHOD

We distributed an online survey to Turkish Society of Cardiology member cardiologists (n = 2789) between January 10 and March 3, 2022.

RESULTS

A total of 308 subjects responded (27.6% females, 62.0% aged 30-44 years). Of these, 42.5% worked at university hospitals, and 44.8% at state hospitals. Smart devices were used by 44.2% (136/308) for personal health monitoring. Additionally, 40.3% (117/290) used social media to provide medical information to patients, while 64.6% (193/299) did so for communication with other physicians. The self-reported recommendation frequencies of wearables, cardiac implantable electronic device telemonitorization, mobile health applications, and teleconsultation/televisit technologies were lower than the proportion of respondents who found DHT beneficial for both patients and physicians. The most frequently mentioned barriers for physicians were increased work burden and responsibilities (78.8%, 193/245), lack of financial compensation (66.9%, 164/245), and lack of relevant training (66.5%, 163/245). For patients, low technological adaptability (81.6%, 200/245), low health literacy (80.4%, 197/245), and low affordability (79.6%, 195/245) were the most frequently mentioned barriers. Additionally, the cost of technologies (69.4%, 170/245), concerns regarding data privacy and security (57.6%, 141/245), and data storage challenges (48.2%, 118/245) were the most significant technical impediments.

CONCLUSION

The findings suggest that although the majority of physicians believe DHT to be beneficial for both themselves and their patients, the frequency of recommendations to patients remains low. A large-scale joint effort is required to address these issues and facilitate the integration of DHT into clinical practice.

Digital Technologies in Heart Failure Management

Heart Failure (HF) is an important public health problem in Turkey and in the world. Hospitalizations due to HF decompensation are associated with increased mortality. The use of digital technologies, especially wearable technologies, is increasing. As physicians, with the use of these devices, patients could be closely followed up and hospitalization, mortality are tried to be prevented by increased awareness of decomposition before clinical symptoms or at the beginning of symptoms. In this review, digital biomarkers, digital technologies, remote monitoring systems and the evidence supporting their use, artificial intelligence applications and the reasons limiting their use of digital technologies in clinical practice will be discussed.

Cardioneuroablation for treatment of carotid sinus syndrome secondary to orofarengeal squamoz cell cancer

INTRODUCTION

Cardioneuroablation may be an alternative to pacing therapy to treat carotid sinus syndrome secondary to inoperable head and neck tumors.

METHODS

We performed, bi-atrial electroanatomic-mapping-guided (a fractionated electrogram-based) cardioneuroablation treatment.

RESULTS

Ablation procedure led to an increase in resting sinus heart rhythm (from 54 to 81 bpm). During the follow-up period of approximately 6 months, neither any bradycardia episodes (sinus bradycardia, sinus pause, AV block, etc.) nor any symptoms were observed in the patient.

CONCLUSION

In this case, we performed successful cardioneuroablation therapy for the first time in a patient with carotid sinus syndrome secondary to oropharyngeal squamous cell carcinoma. This article is protected by copyright. All rights reserved.

Permanent pacing versus cardioneuroablation for cardioinhibitory vasovagal syncope

BACKGROUND

We compared the efficacy and safety of cardioneuroablation (CNA) vs. permanent pacing (PM) for recurrent cardioinhibitory vasovagal syncope (CI-VVS).

METHODS

One hundred sixty-two patients (CNA = 61, PM = 101), age 36 + 11 years) with syncope frequency of 6.7 ± 3.9/year were included in this multicenter study. All patients with CNA were provided by a single center, while patients with PM were provided by 4 other centers. In the CNA arm, an electroanatomic mapping guided approach was used to detect and ablate ganglionated plexus sites. Dual chamber rate drop response (RDR) or close loop stimulation (CLS) transvenous and leadless pacemakers were implanted using standard technique. The primary endpoint was freedom from syncope.

RESULTS

Of 101 patients in the PM group, 39 received dual-chamber pacemaker implants with the CLS algorithm, 38 received dual-chamber pacemakers with the RDR algorithm, and 24 received a leadless pacemaker. At 1-year follow-up, 97% and 89% in the CNA and PM group met the primary endpoint (adjusted HR = 0.27, 95% CI 0.06-1.24, p = 0.09). No significant differences in adverse events were noted between groups. There was no significant association between age (HR:1.01, 95% CI 0.96-1.06, p = 0.655), sex (HR:1.15, 95% CI 0.38-3.51, p = 0.809), and syncope frequency in the past year (HR:1.10, 95% CI 0.97-1.25, p = 0.122) and the primary outcome in univariable analyses.

CONCLUSIONS

After adjustment for patient characteristics, the medium-term syncope recurrence risk of CI-VVS patients who underwent CNA was similar to that of a population of patients undergoing pacemaker implantation with a similar safety profile.

Perspectives on the use of digital health technologies in cardiology among specialists from an ESC member country: results from a survey

Background

Digital health technologies (DHTs) have the potential of facilitating both physicians' and patients' lives with regards to the diagnosis, treatment and follow-up of cardiovascular disease. A huge acceleration in relevant research has been noted particularly after the COVID-19 pandemic.

Purpose

The goal of this study was to determine the reasons for using DHTs in cardiology, as well as the perceived barriers to its use.

Methods

An electronic survey with 43 question multiple-choice questionnaire was conducted between January 10-March 3, 2022. National cardiac society member cardiology fellows in training and specialists were contacted via e-mail (n=2789).

Results

308/2789 (11.04%) subjects responded to the survey (72.40% males, 62.01% aged 30–44 years). 42.53% and 44.81% were affiliated with university hospitals and state hospitals, respectively. 88/297 (29.63%) stated having at least good understanding of DHTs in cardiology. 44.16% utilized smart devices to track their own health status. 117/290 (40.34%) and 193/299 (64.55%) used social media platforms to share medical information with their patients and other physicians, respectively. WhatsApp and Instagram were the most popular platforms for sharing with patients (92/117, 78.63% and 48/117, 41.03%), while WhatsApp and Twitter were the most popular platforms for sharing with other physicians (151/193, 78.24% and 91/193, 47.15%). Considerations and recommendation/utilization patterns of DHTs by physicians are summarized in Table 1. Perceived barriers to the use of DHTs in cardiology is shown on Figure 1 (A: physician-related, B: patient-related, C: technical).

Conclusion

Findings suggest that nearly half of the physicians use DHTs to collect their own health data and use social media to disseminate health information. The majority of physicians believe that DHT is beneficial to both themselves and their patients, and that DHT use in cardiology has increased as a result of the COVID-19 pandemic. To overcome the challenges to the use of DHTs in cardiology, a multilayered collaborative effort involving patient and professional organizations, as well as technical stakeholders and lawmakers, is required.

Funding Acknowledgement

Type of funding sources: None.

Cardioneuroablation for Treatment of Atrioventricular Block

[Figure: see text].

The anatomical basis behind the neuromodulation effects associated with pulmonary vein isolation

The anatomical basis underlying the neuromodulation effects seen with pulmonary vein (PV) isolation (PVI) is not fully understood. Left atrial (LA) electro-anatomical maps of 38 patients who underwent catheter cardioneuroablation for vagally mediated bradycarrhythmias were studied. During the procedure, LA ganglionic plexi (GPs) were systematically identified and ablated. Design PVI lines were created on these maps by a blinded observer, and the degree of overlap between four GPs and individual PVs was assessed. Here, 1.7 ± 7 (35.5 ± 17.0%) of the total 31.6 ± 10 GP ablation sites per patient were found to overlap with the design PVI lines. The overlap was higher for the right-sided GPs, p < .001. The degree of GP-PV overlap varied: 1 PV in 5 (13.2%) patients, 2 PVs in 15 (39.2%), 3 PVs in 16 (42.1%), and all 4 PVs in 2 (5.3%). No patient had zero GP-PV overlap. A vagal response was most commonly observed during ablation at the left superior GP (89.5%), while a sympathetic response was observed most often during the right superior GP ablation (97.4%). Some degree of GP-PV antral overlap is the norm, and this is more pronounced for the right-sided PVs. There is significant individual variability in the degree of overlap which may explain why neuromodulation effects are not seen universally following PVI.

QTc shortening effect of ganglionated plexi ablation

BACKGROUND

In previous studies, patients undergoing ablation of ganglionated plexi (GPA) for vagally mediated bradyarrhythmias were noted to have shortening of their corrected QT interval (QTc).

AIMS

To compare the effects of GPA (group 1) to pulmonary vein isolation + GPA (group 2) on QTc.

MATERIAL AND METHODS

We enrolled 39 patients, n = 25 in group 1 and n = 14 in group 2. QTc was calculated at baseline, at 24 h after ablation, and at 9-12 months in the follow-up. Recurrent syncope, asystole >2 s, and/or second- or third-degree AVB episodes were carefully documented as the primary outcome in group 1. Any atrial arrhythmia ≥30 seconds documented on 24-h Holter monitoring was defined as the primary outcome in group 2.

RESULTS

The mean follow-up time was 14.9 ± 4 months. Acute success was achieved in all cases. In whole cohort, a significant shortening on QTcBazett, QTcFramingham, QTcFredericia, and QTcHodges was observed [416 vs 398ms (p = .002), 411vs 378 ms (p < .001), 412 vs 379ms (p < .001), and 420 vs 383ms (p < .001), respectively]. In the linear mixed model analysis, the longitudinal reduction tendency in the QTc level was more pronounced in group 1. Event-free survival was detected in 90.7% (59/65) of cases.

DISCUSSION

Our results demonstrate a significant shortening of QTc in addition to high medium-term success rates after GPA. Pulmonary vein isolation + GPA was associated with lower QTc shortening effect which implies structural disease may change electrophysiological response to ablation. The most likely mechanism is the effect of GPA on the sympathetic system.

Ultrasound guided percutaneous cephalic venipuncture for implantation of cardiac implantable electronic devices

BACKGROUND

Preoperative ultrasound (US) for cephalic cut-down is related to shorter procedure time and higher success rate. This study aimed to assess efficiency of US-guided percutaneous cephalic vein (CV) puncture for placement of cardiac implantable electronic devices (CIEDs).

METHODS

Patients undergoing a procedure including both US-guided pectoral nerve block (PECS) and percutaneous CV puncture were retrospectively investigated. Patient medical history and demographic data was collected. Clinical features of the procedures and intra- and post-operative complications occurring were collected from patient records. Clinical data included target vessel features, and the time taken for the following: CV puncture; CV and PECS puncture; total procedure.

RESULTS

In total 34 patients had CV puncture with US-guided PECS block was attempted in all patients and the procedure was successful in 27 of 34 (79.4%) patients. The total number of CV puncture attempts was 62 for 34 leads (mean attempts per lead = 1.82). The mean ± standard deviation time for CV puncture was 137.5 ± 27.4 s. There were no venous access-related complications.

CONCLUSION

US-guided CV puncture appears feasible and safe with an acceptable success rate. In case of failure of the US-guided axillary or subclavian vein approach, it may be preferred as an alternative to the cephalic cut-down procedure, where the success rate is relatively lower and the risk of bleeding is higher.

Ultrasound guided percutaneous cephalic venipuncture for implantation of cardiac implantable electronic devices

BACKGROUND

Preoperative ultrasound (US) for cephalic cut-down is related to shorter procedure time and higher success rate. This study aimed to assess efficiency of US-guided percutaneous cephalic vein (CV) puncture for placement of cardiac implantable electronic devices (CIEDs).

METHODS

Patients undergoing a procedure including both US-guided pectoral nerve block (PECS) and percutaneous CV puncture were retrospectively investigated. Patient medical history and demographic data was collected. Clinical features of the procedures and intra- and post-operative complications occurring were collected from patient records. Clinical data included target vessel features, and the time taken for the following: CV puncture; CV and PECS puncture; total procedure.

RESULTS

In total 34 patients had CV puncture with US-guided PECS block was attempted in all patients and the procedure was successful in 27 of 34 (79.4%) patients. The total number of CV puncture attempts was 62 for 34 leads (mean attempts per lead = 1.82). The mean ± standard deviation time for CV puncture was 137.5 ± 27.4 s. There were no venous access-related complications.

CONCLUSION

US-guided CV puncture appears feasible and safe with an acceptable success rate. In case of failure of the US-guided axillary or subclavian vein approach, it may be preferred as an alternative to the cephalic cut-down procedure, where the success rate is relatively lower and the risk of bleeding is higher.

Elevated levels of short-term blood pressure variability: A marker for ascending aortic dilatation in hypertensive patients

Background: Ascending aortic aneurysms are one of the primary causes of mortality. However, not much is known about the etiologies of aortic aneurysm. Recently, in hypertensive (HT) patients, blood pressure variability (BPV) has been recommended as a remarkable risk factor for adverse cardiovascular outcomes. This study aimed to explore the association between short-term BPV and ascending aortic dilatation (AAD).Methods: In this study, a total of 53 HT patients with AAD (aortic size index [ASI] ≥21 mm/m²) and 126 HT patients with a normal ascending aortic diameter (ASI <21 mm/m²) were included. Baseline, echocardiographic, and 24-h ambulatory blood pressure (BP) monitoring results were compared between groups. Standard deviation (SD) and coefficient of variation (CV) of BP were used to determine short-term BPV.Results: Except for daytime SBP values, daytime, nighttime, and 24-h mean systolic (SBP) and diastolic (DBP) BP levels were similar between groups. Compared with the HT patients with normal AA, daytime SBP, daytime SD of SBP, 24-h SD of SBP, daytime CV of SBP, and 24-h CV of SBP were significantly higher in HT patients with AAD. Compared with the HT patients with normal AA, the frequency of nondipper pattern was higher and dipper pattern was lower in HT patients with AAD. In multivariate logistic regression analysis, the daytime CV of SBP, daytime SD of SBP, 24-h SD of SBP, daytime SBP, and left ventricular mass index were independently associated with AAD. In receiver operating characteristic curve analysis, the daytime CV of SBP levels of >12.95 had a sensitivity of 61% and a specificity of 59% (area under the curve, 0.659; 95% CI, 0.562-0.756; P= .01); moreover, daytime SD of SBP > 16.4 had sensitivity of 62% and specificity of 61% (AUC, 0.687; 95% CI, 0.591-0.782; P< .001).:Conclusion Increased short-term BPV is independently associated with AAD and may be recommended as a remarkable factor risk for AAD in HT patients.

Fractionated Mapping-Guided Ablation Strategy in Patients with Long-Standing Persistent Atrial Fibrillation: a Case Series

Although pulmonary vein isolation (PVI) remains the cornerstone of ablation for paroxysmal atrial fibrillation (AF), optimal ablation strategy for long-standing persistent AF (LSPAF) remains unclear. This article presents two patients with LSPAF in whom acute AF termination was achieved during ablation by using fractionated-guided extended PVI, posterior wall isolation, and mitral isthmus.

Catheter Ablation of Atrioventricular Block: From Diagnosis to Selection of Proper Treatment

A 39-year-old man presented with recurrent syncope. A 12-lead electrocardiogram and a 24-h Holter recording demonstrated atypical persistent Mobitz type I and high-degree atrioventricular block, respectively. The functional nature of the atrioventricular block was confirmed by atropine challenge, exercise testing, and electrophysiological study. The patient was successfully treated with a cardioneuroablation procedure. (Level of Difficulty: Intermediate.).

Usefulness of post-procedural heart rate response to predict syncope recurrence or positive head up tilt table testing after cardioneuroablation

Aims

Previous reports have suggested that cardioneuroablation (CNA) can be effective in reducing syncopal recurrences in patients with vasovagal syncope (VVS). This study assessed the efficacy of CNA in preventing a positive response to head-up tilt testing (HUT).

Methods and results

This is a single-centre retrospective study reviewing prospectively collected data. Fifty-one consecutive patients with VVS were included in the study. After confirmation of &gt;3 s asystole on HUT, all patients underwent CNA. Head-up tilt testing was repeated 1 month after CNA. The main outcome measures were recurrence of syncope episode and positive response on HUT. During a median follow-up period of 11 months (interquartile range 3–27 months), all but 3 (5.8%) of 51 patients were free of syncope. Repeated HUTs were negative in 44 (86.2%) patients. When patients with recurrent syncope were excluded, vasodepressor response was seen in three cases and cardioinhibitory response in one case, respectively. Cardioneuroablation caused significant and durable shortening of RR interval in all cases. This effect was significantly higher in patients without positive HUT responses.

Conclusion

This pilot study shows that CNA can effectively prevent recurrent syncopal episodes in patients with refractory VVS. Head-up tilt testing seems as a valuable diagnostic tool not only to select suitable candidates and but also to evaluate success of CNA.

Initial experience with fractionation mapping-guided ablation strategy in patients with long-standing persistent atrial fibrillation

PURPOSE

We aimed to define the role of extended pulmonary vein isolation (PVI), posterior wall isolation, and mitral isthmus lines to eliminate electrograms exhibiting fractionation pattern during stepwise ablation on acute atrial fibrillation (AF) termination rate in patients with long-standing persistent AF (LSPAF).

METHODS

Twelve patients with LSPAF underwent ablation during AF. Using the fractionation mapping tool of the Ensite™ (Abbott Medical, Chicago, USA) system, sites exhibiting discrete atrial complexes and consistent activation sequence were mapped. The areas with a fractionation score above 4 were accepted as potential drivers for AF. During stepwise ablation consisting of circumferential PVI, roof and floor lines for posterior wall isolation, and mitral isthmus lines, ablation lines were extended toward potential AF drivers on the fractionation map as much as possible until sinus was achieved by ablation.

RESULTS

Fractionation-guided ablation caused acute AF termination in 8 of 12 patients. In 6 of 12 cases, AF returned to sinus rhythm during the extended ablation. In 2 patients, AF shifted to sinus after cavotricuspid isthmus ablation. Sinus was achieved by cardioversion in 3 of cases. Procedural failure was seen in one case with significant scar tissue. During a mean follow-up of 31.5 ± 11 months, overall arrhythmia-free survival was 92% with 2 procedures.

CONCLUSIONS

This pilot study demonstrates that fractionation mapping-guided ablation may provide an adjunctive benefit in terms of acute AF termination in patients with LSPAF. These results should be confirmed by larger, randomized, comparison studies between linear ablation and extended ablation without elimination of electrograms (EGMs) with fractionation.

Moving Air in the Esophagus During Cryoballoon Ablation

A 56-year-old male patient underwent cryoballoon ablation for symptomatic paroxysmal atrial fibrillation. Massive air movement reminiscent of an air esophagram was detected during cryoballoon application in the right superior pulmonary vein. In this case report, we sought to consider all possible explanations of this finding.

P1127Occurrence, management and outcomes of iatrogenic aortic dissections as a complication of catheter ablation. A multicenter study

Background

Data on occurrence, management and outcomes of iatrogenic aortic dissections (IAD) as a complication of catheter ablation (CA) do not exist.

Purpose

To evaluate multicenter data on occurrence, management and outcomes of IAD as a complication of CA.

Methods

Data on occurrence, management and outcomes of documented vascular dissections from 10 centers were evaluated.

Results

IADs occurred in 7 patients (2 females, age 63 ± 8 years). Indications for CA were frequent premature ventricular complexes (PVC)/ventricular tachycardia (VT) in 6 patients (86%) and left-sided accessory pathway in the remaining one (14%). Hypertension was most frequent comorbidity (4 pts, 57%).  All IADs occurred during retrograde advancement of ablation catheter. In the vast majority of patients creation of IAD during catheter advancement was not associated with any symptoms (6 pts, 86%). IAD was initially detected using trans-luminal angiogram in 5 (71%) and further confirmed using computed tomography (CT) (5 pts, 71%), conventional angiography (2 pts, 28%) and ultrasound (2 pts, 28%). One IAD was detected during CT scan performed for other indication after CA. There was one IAD-related death and IAD was evaluated post-mortem. Follow-up lasted 10 ± 19 months. Four patients were treated conservatively, one patient underwent descending aorta stenting and one femoral artery stenting.

Conclusions

IAD during CA is a rare but can be devastating. Early recognition can be difficult. Conservative management of IAD is an option of treatment.

Utility of Head up Tilt Table Testing to Demonstrate Selective Denervation of the Sinus Node after Cardioneuroablation

A 65-year-old female who underwent cardioneuroablation for recurrent vasovagal syncope presented for 6 month follow-up visit. She had no further syncope after the procedure. A follow up tilt table testing (TT) demonstrated sinus tachycardia and variable degrees of atrioventricular block (AVB) after sublingual glyceryl trinitrate. She had no syncope during the test. As per existing knowledge, the occurrence of AVB during vasovagal reaction induced by TT should be preceded by sinus rhythm slowing.  In this patient, sinus tachycardia during TT demonstrates highly specific denervation of ganglion cells which send postganglionic fibers directly to the sinus node without obvious influence on the atrioventricular node.

Why is pulmonary vein isolation not enough for vagal denervation in all cases?

Pulmonary vein isolation (PVI) may cause vagal response during radiofrequency application or increase on heart rate after ablation. All those responses are related to inadvertent ablation effect on ganglionated plexi. In the present case, we aimed to explain why vagal response effects of PVI are not same in all cases.

Usage of a new mapping algorithm to detect possible critical substrate for continuity of atrial fibrillation: fractionation mapping in preliminary experience

Although treatment of atrial fibrillation (AF) classically focuses on eliminating the pulmonary vein (PV) triggers, isolation of PVs is associated with limited success rates in patients with persistent AF. The role of the left atrial appendage (LAA) as both trigger and driver in arrhythmogenesis of AF was previously demonstrated. In the present case, fractionation mapping software of Ensite system was firstly tested to detect critical substrate during AF. Focusing on the width and continuity of fractionation pattern, the LAA was accepted as main driver for maintenance of AF. Ablation in fractionated electrograms around the LAA caused acute AF termination. After isolation of the LAA, no AF was inducible with atrial stimulation with and without isoproterenol infusion. Fractionation mapping may be used to detect potential importance of the LAA in AF continuity.

Vagal responses during cardioneuroablation on different ganglionated plexi: Is there any role of ablation strategy?

BACKGROUND

Cardioneuroablation has been used to treat vagally mediated bradyarrhythmias (VMB). The aim of this study is to assess vagal response (VR) characteristics during radiofrequency catheter ablation (RFCA) with different ganglionated plexus (GP) order.

METHODS

A total of 49 consecutive patients with VMB who underwent cardioneuroablation were enrolled. GPs were identified by electroanatomic-mapping-guided strategy. After all GP targets have been identified, patients were divided into 2 groups according to GP ablation strategy. In the left side first group, ablation order of GPs were left superior GP (LSGP), left inferior GP (LIGP), right superior GP (RSGP), and right inferior GP (RIGP). In the right side first group, ablation order was RSGP, RIGP, LSGP, and LIGP.

RESULTS

In the left side first group, LSGP was the most common GP site at which a VR was observed (36 of 40 cases, 90%). LIGP causes a VR in 9 of 40 (22.5%) cases. In the right side first group, VR was seen only 2 of 9 (22.2%) cases. Comparison of ablation strategy demonstrated a significant difference in VR during ablation on LSGP between groups. Despite, LSGP was the most common GP site at which a VR was observed both groups (90% in left side first group vs 11.1% in right side first group, p < 0.0001). In remaining GPs, VRs were not dependent on the ablation strategy and were not statistically different between groups.

CONCLUSION

The present study demonstrates that the characteristics of VR during RFCA might change according to ablation order of GPs.

Acute Procedural Complications of Cryoballoon Ablation: A Comprehensive Review

Catheter ablation is increasingly performed for treatment of atrial fibrillation (AF). Balloon based procedures have been developed aiming at safer, easier and more effective treatment as compared to point to point ablation. In the present review article, we aimed to discuss acute procedural complications of cryoballoon ablation.

Reprogramming the tachycardia parameters with long-detection strategy in patients with pre-existing implantable cardioverter-defibrillator

Background: A long-detection interval (LDI) programming has been proved to reduce shock therapy in patients who underwent de novo implantable cardioverter defibrillator (ICD) implantation. We aimed to evaluate effectiveness and safety of this new strategy in old ICD recipients. Methods: We included 147 primary prevention patients with ischaemic and non-ischaemic aetiology. Conventional setting parameters (18 of 24 intervals to detect ventricular arrhythmias (VA's)) were reprogrammed with LDI strategy (30 of 40 intervals to detect VA's). One monitoring zone (between 360 and 330 ms) and two therapy zones were programmed, treating all rhythms of cycle length <330 ms that met the duration criterion of 30/40 intervals and were discriminated as ventricular tachycardia/ventricular fibrillation (VT/VF). The supraventricular tachycardia (SVT) discriminators were used in all patients. Results: At a median follow-up of 24 months, 12.9% (n = 19) of patients received shock therapies (± antitachycardia pacing (ATP)). Appropriate and inappropriate shocks occurred in 7.5 and 5.4% of patients during follow-up, respectively. Only one patient experienced an arrhythmic syncope during the follow-up period. There was no death related to LDI programming. The LDI programming helped to stop unnecessary in 10 patients (6.8%), who otherwise would have been treated in the conventional programming. Conclusions: LDI programming was found safe and effective. Hence, old ICD recipients will benefit from this strategy.

Potential usage of cardioneuroablation in vagally mediated functional atrioventricular block

An increase in parasympathetic tone may be the main cause of some transient or permanent atrioventricular block cases. Some of these patients, defined as vagally mediated functional atrioventricular block, may be severely symptomatic and refractory to conventional therapies and may necessitate cardiac pacing. Cardioneuroablation is a relatively new strategy for management of patients with excessive vagal activation based on radiofrequency catheter ablation of main ganglionated plexi around the heart. Present review was dedicated to discuss potential usage of cardioneuroablation in patients with vagally mediated functional atrioventricular block.

What role might cardioneuroablation strategy have in syncope guidelines?

Vasovagal syncope (VVS) is the most common type of syncope. Although it is not related to an increase in mortality, recurrent syncope episodes may be disabling and reduce the quality of life. There are no optimal treatment strategies currently available, especially for the cardioinhibitory type of VVS. Cardioneuroablation (CNA) is a relatively novel technique that aims to eliminate vagal efferent output during VVS. The objective of this review was to explore the potential role of CNA strategy in syncope guidelines.

A new and simple technique for vagal ganglia ablation in a patient with functional atrioventricular block: Electroanatomical approach

Increased parasympathetic tone may cause symptomatic functional atrioventricular block (AVB) and necessitate pacemaker implantation. In these patients, where there is no structural damage to the conduction system, removal of the vagal activity using radiofrequency ablation seems to be a theoretically rational approach. Several methods have been used to determine suitable areas for vagal ganglia ablation. The aim of this report was to describe a new method to detect parasympathetic innervation sites without the need to use additional equipment or extend procedure time. A 51-year-old man was referred to the clinic for implantation of a permanent pacemaker because of symptomatic second-degree AVB and recurrent syncope. The functional nature of the AVB and a supra-Hisian location were verified with standard electrocardiography, Holter recordings, atropine sulfate test, and a standard electrophysiological study. Using conventional recordings, the electrograms were divided into 3 subgroups and sites demonstrating a fractionated pattern were targeted. All of the fractionated electrogram sites considered suitable for usual ganglion settlement were ablated. Biatrial ablation was initiated from the left atrial side. During left atrial ablation, the intrinsic basic cycle length of sinus node accelerated to 800 milliseconds despite AVB persistence. Subsequently, 1:1 atrioventricular conduction was achieved when ablation was applied around the coronary sinus ostium. The patient was completely asymptomatic, experiencing no episodes of dizziness or syncope, and was taking no medications at the end of 9 months of follow-up. In conclusion, electroanatomically guided vagal ganglia ablation may be a good alternative to pacemaker implantation in well-selected patients with functional AVB.

Transient ST-segment elevation due to coronary slow flow during cryoballoon application

This report is a description of a rare case of transient ST-segment elevation during cryoballoon application for paroxysmal atrial fibrillation (PAF). A 74-year-old male with symptomatic PAF was referred to the center for ablation. During cryoablation of the left superior pulmonary vein (188 seconds, -48°C), ST-segment elevation in the anterolateral leads was observed suddenly, though without any significant complaint. Upon the increase in the ST segment, the cryoapplication was immediately terminated. Coronary artery angiography was performed less than 5 minutes after balloon deflation and demonstrated coronary slow flow with a corrected Thrombolysis In Myocardial Infarction (TIMI) frame count of 48.4 (normal range: 21±3) in the left anterior descending artery (LAD). There was no significant flow-limiting lesion, coronary vasospasm, thromboembolus, or air embolus in any coronary vessel. The TIMI frame count for the right coronary artery and the circumflex artery was normal. The ST-segment elevation gradually returned to the baseline in 14 minutes without any intervention. A control TIMI frame count of the LAD was 22. A decision was made not to repeat the cryoapplication in this vein because there was both an entrance and an exit block. The other 3 pulmonary veins were then isolated uneventfully. The patient was discharged from the hospital the next day without symptoms or unusual electrocardiogram activity.

Can We Predict Vagal Response to Cryoballoon Application Using Intracardiac Recordings?

The effects of cryoballoon (CB) ablation in non-pulmonary vein sites have not clearly elucidated. Herein we present a new definition method which helps to predict autonomic modification effect of CB application using atrial electrogram (EGM) characteristics and vagal responses (VRs). A 54-year-old man underwent pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation. Both atria were mapped with the aid of electroanatomical mapping system prior to ablation procedure. The atrial EGMs were divided into 3 groups according to duration, amplitude, and number of deflections. The sites demonstrating fractionated pattern on 2.5 centimeters outside of pulmonary vein ostia were tagged on the mapping to predict the relationship between VR and EGM characteristics during CB application. CB application in the PV demonstrating intensive fractionated EGMs caused a significant VR. We concluded that our case may be starting point to understand mechanism of PVI induced VR during CB application.

Stepwise Approach to the Different Parts of Vasovagal Syncope in a Patient Undergoing Cardioneuro Ablation

A 30-year-old man underwent ganglionated plexi ablation due to cardioinhibitory type vasovagal syncope with asystole. After asymptomatic period of 15-month following the procedure, the patient experienced 2 new syncope episodes. Tilt test demonstrated vasodepressor response without significant bradycardia. Following the onset of midodrine therapy, the patient was asymptomatic for 1 year and tilt test demonstrate normal response.

Elevated levels of vitamin B12 in chronic stable heart failure: a marker for subclinical liver damage and impaired prognosis

Background

Elevated vitamin B12 is a sign for liver damage, but its significance in chronic stable heart failure (HF) is less known. The present study investigated the clinical correlates and prognostic significance of vitamin B12 levels in stable systolic HF.

Methods

A total of 129 consecutive patients with HF and 50 control subjects were enrolled. Data regarding demographics, clinical signs, therapeutic and conventional echocardiographic measurements were recorded for all patients. Right-sided HF was defined as the presence of at least one of the typical symptoms (ankle swelling) or specific signs (jugular venous distention or abdominojugular reflux) of right HF. Cox proportional hazards regression analyses were performed to determine the independent prognostic determinants of mortality.

Results

Baseline B12 levels in HF patients (n=129) with and without right sided HF were significantly higher compared to healthy controls (n=50): Median 311 pg/mL and 235 pg/mL vs 198 pg/mL, respectively (P=0.005). Folic acid levels were similar between the study groups. Age, ejection fraction, left atrial size, estimated glomerular filtration rate, and direct and indirect bilirubin levels were significantly correlated to serum B12 level in univariate analysis. In multivariate analysis, independent correlates of B12 were direct bilirubin (R=0.51, P<0.001) and age (R=0.19, P=0.028). Patients with HF were followed-up for a median period of 32 months. Median B12 levels were significantly higher in patients who subsequently died (n=35) compared to survivors, but folic acid was not different between the two groups. ROC analysis showed that B12 values ≥270 pg/mL had 80% sensitivity and 58% specificity for predicting all-cause mortality (area under the curve=0.672, 95% CI=0.562−0.781; P=0.003). However, in Cox regression analysis, only left atrial diameter, level of direct bilirubin, and the presence of abdominojugular reflux were independent predictors of death.

Conclusion

Increased B12 in stable HF patients is associated with increased direct bilirubin due to right HF, indicating a cardiohepatic syndrome, but neither B12 nor folic acid are independently associated with mortality.

Renal sympathetic denervation assisted treatment of electrical storm due to polymorphic ventricular tachycardia in a patient with cathecolaminergic polymorphic ventricular tachycardia

Electrical storm (ES) is not a rare clinical entity. Sympathetic hyperactivity may play critical role in development and continuation of ES. Some recent reports have demonstrated that catheter-based renal sympathetic denervation (RSD) may reduce sympathetic activation and have a potential role in reducing arrhythmic burden. A 46-year-old man was admitted to clinic with frequent implantable cardioverter defibrillator shocks and ES related to catecholaminergic polymorphic ventricular tachycardia (VT). Tachycardia was unresponsive to administration of beta-blockers, verapamil, and flecainide. Catheter ablation failed to suppress initial premature ventricular contractions. Based on aggravating effects of sympathetic system in clinical tachycardia, decision was made to perform RSD. After the procedure, sinus rhythm was achieved and no polymorphic VT was detected. Sustained monomorphic VT with right ventricular origin was successfully ablated via endocardial radiofrequency ablation. This new treatment modality may be a potential alternative method for patients in whom other ablative strategies have been unsuccessful.