Clinical application of virtual reality in patients with cardiovascular disease: state of the art.

Virtual reality offers a multisensory experience to patients, allowing them to hear, watch, and interact in a virtual environment. Immersive virtual reality is particularly suitable for the purpose of completely isolating patients from the external environment to transport them away from the suffering related to the disease. On this state of the art, we summarize the available literature on the effectiveness of virtual reality on various physical and psychological outcomes in patients with atherosclerotic cardiovascular disease. Virtual reality has been employed in the cardiovascular field in various settings such as cardiac rehabilitation, interventional cardiology, and cardiac surgery. This technology offers promising opportunities to improve several outcomes related to cardiovascular disease, but further research is needed to entirely capture its benefits and to standardize the intervention.

Computer-aided detection of arrhythmogenic sites in post-ischemic ventricular tachycardia.

Nowadays, catheter-based ablation in patients with post-ischemic ventricular tachycardia (VT) is performed in arrhythmogenic sites identified by electrophysiologists by visual inspection during electroanatomic mapping. This work aims to present the development of machine learning tools aiming at supporting clinicians in the identification of arrhythmogenic sites by exploiting innovative features that belong to different domains. This study included 1584 bipolar electrograms from nine patients affected by post-ischemic VT. Different features were extracted in the time, time scale, frequency, and spatial domains and used to train different supervised classifiers. Classification results showed high performance, revealing robustness across the different classifiers in terms of accuracy, true positive, and false positive rates. The combination of multi-domain features with the ensemble tree is the most effective solution, exhibiting accuracies above 93% in the 10-time 10-fold cross-validation and 84% in the leave-one-subject-out validation. Results confirmed the effectiveness of the proposed features and their potential use in a computer-aided system for the detection of arrhythmogenic sites. This work demonstrates for the first time the usefulness of supervised machine learning for the detection of arrhythmogenic sites in post-ischemic VT patients, thus enabling the development of computer-aided systems to reduce operator dependence and errors, thereby possibly improving clinical outcomes.

Parylene C-Based, Breathable Tattoo Electrodes for High-Quality Bio-Potential Measurements.

A breathable tattoo electrode for bio-potential recording based on a Parylene C nanofilm is presented in this study. The proposed approach allows for the fabrication of micro-perforated epidermal submicrometer-thick electrodes that conjugate the unobtrusiveness of Parylene C nanofilms and the very important feature of breathability. The electrodes were fully validated for electrocardiography (ECG) measurements showing performance comparable to that of conventional disposable gelled Ag/AgCl electrodes, with no visible negative effect on the skin even many hours after their application. This result introduces interesting perspectives in the field of epidermal electronics, particularly in applications where critical on-body measurements are involved.

Spectral characterisation of ventricular intracardiac potentials in human post-ischaemic bipolar electrograms.

Abnormal ventricular potentials (AVPs) are frequently referred to as high-frequency deflections in intracardiac electrograms (EGMs). However, no scientific study performed a deep spectral characterisation of AVPs and physiological potentials in real bipolar intracardiac recordings across the entire frequency range imposed by their sampling frequency. In this work, the power contributions of post-ischaemic physiological potentials and AVPs, along with some spectral features, were evaluated in the frequency domain and then statistically compared to highlight specific spectral signatures for these signals. To this end, 450 bipolar EGMs from seven patients affected by post-ischaemic ventricular tachycardia were retrospectively annotated by an experienced cardiologist. Given the high variability of the morphologies observed, three different sub-classes of AVPs and two sub-categories of post-ischaemic physiological potentials were considered. All signals were acquired by the CARTO® 3 system during substrate-guided catheter ablation procedures. Our findings indicated that the main frequency contributions of physiological and pathological post-ischaemic EGMs are found below 320 Hz. Statistical analyses showed that, when biases due to the signal amplitude influence are eliminated, not only physiological potentials show greater contributions below 20 Hz whereas AVPs demonstrate higher spectral contributions above ~ 40 Hz, but several finer differences may be observed between the different AVP types.

Predictors of inappropriate shock in Brugada syndrome patients with a subcutaneous implantable cardiac defibrillator.

BACKGROUND: Subcutaneous implantable cardioverter defibrillators (S-ICDs) avoid complications secondary to transvenous leads, but inappropriate shocks (ISs) are frequent. Furthermore, IS data from patients with Brugada syndrome (BrS) with an S-ICD are scarce. OBJECTIVE: We aimed to establish the frequency and predictors of IS in this population. METHODS: We analyzed the clinical and electrocardiographic characteristics, automated screening test data, device programming, and IS occurrence in adult patients with BrS with an S-ICD. RESULTS: Thirty-nine patients were enrolled (69% male, mean age at diagnosis 46 ± 13 years, mean age at implantation 48 ± 13 years). During a mean follow-up of 26 ± 21 months, 18% patients experienced IS. Patients with IS were younger at the time of diagnosis (36 ± 8 vs. 48 ± 13 years, p = .018) and S-ICD implantation (38 ± 9 vs. 50 ± 23 years, p = .019) and presented with spontaneous type 1 Brugada electrocardiogram pattern more frequently at diagnosis or during follow-up (71% vs. 25%, p = .018). During automated screening tests, patients with IS showed lower QRS voltage in the primary vector in the supine position (0.58 ± 0.26 vs. 1.10 ± 0.35 mV, p = .011) and lower defibrillator automated screening score in the primary vector in the supine (123 ± 165 vs. 554 ± 390 mV, p = .005) and standing (162 ± 179 vs. 486 ± 388 mV, p = .038) positions. Age at diagnosis was the only independent predictor of IS (hazard ratio = 0.873, 95% confidence interval: 0.767-0.992, p = .037). CONCLUSION: IS was a frequent complication in patients with BrS with an S-ICD. Younger age was independently associated with IS. A more thorough screening process might help prevent IS in this population.

Brugada phenocopy in a patient with unstable angina and three-vessel coronary artery disease.

A 52-year-old male was admitted with unstable angina and three-vessel coronary artery disease. Electrocardiography (ECG) changes consistent with type-1 Brugada ECG pattern were noted during admission. The patient was asymptomatic for syncope and had no family history of sudden cardiac death, ICD implantation, and Brugada syndrome. After coronary by-pass graft the Brugada ECG pattern resolved, and ajmaline test did not elicit type-1 ECG pattern, confirming the suspicion of Brugada phenocopy.

Safety, efficacy, and reproducibility of cavotricuspid isthmus ablation guided by the ablation index: acute results of the FLAI study.

AIMS: Ablation index (AI) is a marker of lesion quality during catheter ablation that incorporates contact force, time, and power in a weighted formula. This index was originally developed for pulmonary vein isolation as well as other left atrial procedures. The aim of our study is to evaluate the feasibility and efficacy of the AI for the ablation of the cavotricuspid isthmus (CTI) in patients presenting with typical atrial flutter (AFL). METHODS AND RESULTS: This prospective multicentre non-randomized study enrolled 412 consecutive patients with typical AFL undergoing AI-guided cavotricuspid isthmus ablation. The procedure was performed targeting an AI of 500 and an inter-lesion distance measurement of ≤6 mm. The primary endpoints were CTI 'first-pass' block and persistent block after a 20-min waiting time. Secondary endpoints included procedural and radiofrequency duration and fluoroscopic time. A total of 412 consecutive patients were enrolled in 31 centres (mean age 64.9 ± 9.8; 72.1% males and 27.7% with structural heart disease). The CTI bidirectional 'first-pass' block was reached in 355 patients (88.3%), whereas CTI block at the end of the waiting time was achieved in 405 patients (98.3%). Mean procedural, radiofrequency, and fluoroscopic time were 56.5 ± 28.1, 7.8 ± 4.8, and 1.9 ± 4.8 min, respectively. There were no major procedural complications. There was no significant inter-operator variability in the ability to achieve any of the primary endpoints. CONCLUSION: AI-guided ablation with an inter-lesion distance ≤6 mm represents an effective, safe, and highly reproducible strategy to achieve bidirectional block in the treatment of typical AFL.

Conservative Management of Spontaneous Coronary Artery Dissection.

Spontaneous coronary artery dissection (SCAD) is caused by separation of the vessel wall and hematoma development. We demonstrate that SCAD often resolves spontaneously, with an average period of 35 days from the event usually sufficient to demonstrate angiographic healing.

Reproducibility of pulmonary vein isolation guided by the ablation index: 1-year outcome of the AIR registry.

BACKGROUND: Ablation index (AI) is a new lesion quality marker that has been demonstrated to allow a high single-procedure arrhythmia-free survival in single-center studies. This prospective, multi-center study was designed to evaluate the reproducibility of pulmonary vein (PV) isolation guided by the AI. METHODS: A total of 490 consecutive patients with paroxysmal (80.4%) and persistent AF underwent first time PV isolation and were divided in four study groups according to operator's preference in choosing the ablation catheter (a contact force (ST) or contact force surround flow (STSF) catheter) and the AI setting (330-450 or 380-500 at anterior wall or posterior wall, respectively). RESULTS: At 12 months a high rate of freedom from AF recurrences was observed in patients with both paroxysmal and persistent AF (91% vs 83.3%; P = .039). There was no difference in the rate of AF recurrence among the four study groups (4.5% in group ST330-450, 12.2% in group ST 380-500, 14.9% in group STSF330-450, 9.4% in group STSF380-500; P = .083). Recurrence was also similar between patients treated with a ST (8%) or STSF catheter (12.1%; P = .2), and within patients targeting an AI settings of 330 to 450 (10.9%) or 380 to 500 (10.3%; P = .64). In patients with paroxysmal AF, there was no difference (P = .12) in the 1-year freedom from AF recurrence among 14 operators that performed ≥10 ablation procedure. CONCLUSIONS: An ablation protocol respecting strict criteria for contiguity and quality lesion resulted in high rate of 1-year freedom from AF recurrence, irrespective of the ablation catheters, AI settings, and operator.

Left Atrial Appendage Occlusion in High Bleeding Risk Patients.

OBJECTIVES: The aim of this study was to investigate the outcomes of left atrial appendage occlusion (LAAO) in high bleeding risk patients suffering atrial fibrillation (AF) and to analyze the different antithrombotic therapies following the intervention. BACKGROUND METHODS: This monocentric study included 68 patients with nonvalvular AF with an absolute contraindication to OAT or at high bleeding risk. Follow-up was done with a clinical visit at 3-6-12 months. RESULTS: Successful LAAO was achieved in 67/68 patients. At discharge, 32/68 patients were on dual antiplatelet therapy (APT), 34/68 were without any antithrombotic therapy or with a single antiplatelet drug, and 2/68 were on anticoagulant therapy. At three-month follow-up visit, 73.6% of the patients did not receive dual APT, of whom 14.7% had no thrombotic therapy and 58.9% were on single antiplatelet therapy. During a follow-up of 1.4 ± 0.9 years, 3/62 patients had late adverse effects (2 device-related thrombus without clinical consequences and 1 extracranial bleeding). The device-related thrombosis was not related to the antithrombotic therapy. CONCLUSIONS: LAAO is feasible and safe and prevents stroke in patients with AF with contraindication to oral anticoagulant therapy. After LAAO, single antiplatelet therapy seems to be a safe alternative to dual antiplatelet therapy, especially in patients at high bleeding risk. No benefit has been observed with dual APT.

Rendered OCT Imaging of an Impressive Stent Malapposition in the Left Main Coronary Artery.

This case emphasizes the need to use intravascular imaging to optimize stent implantation in the left main coronary artery. Despite recommendations, intravascular imaging is still widely under-utilized. The recently developed stent apposition OCT software (OPTIS Stent Optimization Software; Abbott Vascular) confirmed its usefulness in optimizing stent implantation in unprotected left main PCI.

Anomalous Origin of Right Coronary Artery From Left Sinus of Valsalva.

We present the imaging series of a 52-year-old woman with no cardiovascular risk factors who was admitted for acute coronary syndrome without persistent ST elevation (NSTEMI). Coronary angiography and cardiac computed tomography demonstrated anomalous origination of the coronary artery from the opposite sinus (ACAOS), which is an uncommon coronary anomaly; the incidence is about 1.07% in general, and only 0.12%-0.9% in the case of right ACAOS. The clinical consequences can be relevant if the ectopic artery has intramural intussusception or courses between the aorta and pulmonary artery.

Reproducibility of acute pulmonary vein isolation guided by the ablation index.

BACKGROUND: Atrial fibrillation (AF) ablation outcome is still operator dependent. Ablation Index (AI) is a new lesion quality marker that has been demonstrated to allow acute durable pulmonary vein (PV) isolation followed by a high single-procedure arrhythmia-free survival. This prospective, multicenter study was designed to evaluate the reproducibility of acute PV isolation guided by the AI. METHODS: A total of 490 consecutive patients with paroxysmal (80.4%) and persistent AF underwent first time PV encircling and were divided in four study groups according to operator preference in choosing the ablation catheter (a contact force [ST] or contact force surround flow [STSF] catheter) and the AI setting (330 at posterior and 450 at anterior wall or 380 at posterior and 500 at anterior wall). Radiofrequency was delivered targeting interlesion distance ≤6 mm. RESULTS: The rate of first-pass PV isolation (ST330 90 ± 16%, ST380 87 ± 19%, STSF330 90 ± 17%, STSF380 91 ± 15%, P = .585) was similar among the four study groups, whereas procedure (ST330 129 ± 44 minutes, ST380 144 ± 44 minutes, STSF330 120 ± 72 minutes, STSF380 125 ± 73 minutes, P < .001) and fluoroscopy time (ST330 542 ± 285 seconds, ST380 540 ± 416 seconds, STSF330 257 ± 356 seconds, STSF380 379 ± 454 seconds, P < 0.001) significantly differed. The difference in the rate of first-pass isolation was not statistical different (P = .06) among the 12 operators that performed at least 15 procedures. CONCLUSIONS: An ablation protocol respecting strict criteria for contiguity and quality lesion results in high and comparable rate of acute PV isolation among operator performing ablation with different catheters, AI settings, procedure, and fluoroscopy times.

High-resolution Mapping in Patients with Persistent AF.

Ablation of AF through electrical isolation of the pulmonary veins is a well-established technique and a cornerstone in the ablation of AF, although there are a variety of techniques and ablation strategies now available. However, high numbers of patients are returning to hospital after ablation procedures such as pulmonary vein isolation (PVI). Scar tissue (as identified by contact voltage mapping) is found to be present in many of these patients, especially those with persistent AF and even those with paroxysmal AF. This scarring is associated with poor outcomes after PVI. Cardiac mapping is necessary to locate triggers and substrate so that an ablation strategy can be optimised. Multipolar mapping catheters offer more information regarding the status of the tissue than standard ablation catheters. A patient-tailored catheter ablation approach, targeting the patient-specific low voltage/fibrotic substrate can lead to improved outcomes.

QRS Variations During Arrhythmias: Mechanisms and Substrates. Toward a Precision Electrocardiology.

Electrocardiogram (ECG) analysis trying to understand the mechanisms of QRS widening is often problematic. During WCTs, identification of P waves and atrioventricular relationship is often difficult and increasingly so if the number of recording leads available for examination is limited. For this reason, it is necessary to use every information available in an ECG tracing. The goal of this article is to focus on the reasons for QRS variations occurring during tachycardia. Correct interpretation of these data can offer the key to understand the arrhythmia mechanism.

Nonvalvular atrial fibrillation in high-hemorrhagic-risk patients: state of the art of percutaneous left atrial appendage occlusion.

: Atrial fibrillation is the most common cardiac arrhythmia and its prevalence is constantly increasing. The main complications related to atrial fibrillation are death and major stroke. Oral anticoagulant therapy is the cornerstone of management of atrial fibrillation patients at increased stroke risk. Unfortunately, a significant proportion of patients do not receive adequate anticoagulant therapy due to increased or prohibitive hemorrhagic risk. The observation that most thrombi are generated in the left atrial appendage (LAA) had led to the consideration of surgical or percutaneous occlusion as an alternative. During recent years, the WATCHMAN percutaneous occlusion device has proven to be not inferior to anticoagulant therapy for the prevention of thromboembolic events, with the added benefit of a lower rate of hemorrhagic events. Numerous data showed the same results for the AMPLATZER cardiac plug and Amulet devices. Left atrial appendage occlusion (LAAO) often represents the only therapeutic strategy in this group of patients. We describe the current state of the art of percutaneous LAAO in atrial fibrillation patients with a high hemorrhagic risk.

An Impressive Case of "Honeycomb" In-Stent Restenosis.

Our image shows an impressive "honeycomb" pattern of neoatherosclerosis in the context of very late in-stent restenosis. In this case, OCT excluded the most common mechanisms of late in-stent restenosis, underlying the complexity of this unpredictable disease.

Predictors of Zero X-Ray Ablation for Supraventricular Tachycardias in a Nationwide Multicenter Experience.

BACKGROUND: This multicenter, prospective study evaluated the determinants of zero-fluoroscopy (ZFL) ablation of supraventricular tachycardias. METHODS AND RESULTS: Four hundred thirty patients (215 male, 55.4±22.1 years) with indication to electrophysiological study or ablation of supraventricular tachycardias were enrolled. All participating physicians agreed to follow the as low as reasonably achievable policy. A procedure was defined as ZFL when no fluoroscopy was used. The total fluoroscopy time inversely correlated to the number of procedures previously performed by each operator since study start (r=-0.112; P=0.02). Two hundred eighty-nine procedures (67.2%) were ZFL; multivariable analysis identified as predictors of ZFL: procedure after the 30th for each operator, compared with procedures up to the ninth (P=0.011; hazard ratio, 3.49; 95% confidence interval [CI], 1.79-6.80); the type of arrhythmia (P=0.031; electrophysiological study and atrioventricular nodal reentry tachycardia ablation having the highest probability of ZFL; hazard ratio, 6.87; 95% CI, 2.08-22.7 and hazard ratio, 2.02; 95% CI, 1.04-3.91, respectively); the operator's (P=0.002) and patient's age (P=0.009). Among operators, achievement of ZFL varied from 0% to 100%; 8 (22.8%) operators achieved ZFL in <25% of their procedures; 17 (48.6%) operators achieved ZFL in >75% of their procedures. The probability of ZFL increased by 2.8% (hazard ratio, 0.98; 95% CI, 0.97-0.99) as patient's age decreased by 1 year. Acute procedural success was obtained in all cases. CONCLUSIONS: The use of 3-dimensional mapping system completely avoided the use of fluoroscopy in most cases, with very low fluoroscopy time in the remaining and high safety and effectiveness profiles. Achievement of ZFL was predicted by the type of arrhythmia, operator's experience, and patient's age.