Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

BACKGROUND

Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories.

METHODS

We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5-19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For school-aged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median).

FINDINGS

From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness.

INTERPRETATION

The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity.

FUNDING

UK Medical Research Council, UK Research and Innovation (Research England), UK Research and Innovation (Innovate UK), and European Union.

Modern physiological approach to inappropriate ICD shocks due to atrial fibrillation with very fast ventricular response. A case report

BACKGROUND

Fast-conducting atrial fibrillation misinterpreted as ventricular tachycardia is the leading cause for inappropriate shocks in patients with implantable cardiac defibrillators (ICD). These inappropriate shocks are associated with significant morbidity and mortality and cause great discomfort and stress.

CASE PRESENTATION

We report the case of a patient with ischemic cardiomyopathy, permanent atrial fibrillation, and a single-chamber DF-1 ICD implanted for the primary prevention of sudden cardiac death, who presented for multiple inappropriate internal shocks due to very fast-conducting atrial fibrillation, which was mislabeled as ventricular fibrillation by the ICD. Since the patient was under maximal atrioventricular nodal blocking medical therapy (beta-blockers and digitalis) and we didn`t find any reversible causes for the heart rate acceleration, we opted for rate control with atrioventricular node ablation. To counteract the risk of pacing-induced cardiomyopathy in this patient who would become totally pacemaker-dependent, we successfully performed left bundle branch area pacing. Because the patient`s ICD had a DF-1 connection and the battery had a long life remaining, we connected the physiological pacing lead to the IS-1 sense-pace port of the ICD. The 6-month follow-up showed an improvement in left ventricular function with no more inappropriate shocks.

CONCLUSIONS

Left bundle branch area pacing and atrioventricular node ablation in patients with an implantable single-chamber DF-1 defibrillator and fast-conducting permanent atrial fibrillation is a cost-efficient and very effective method to prevent and treat inappropriate shocks, avoiding the use of an additional dual-chamber or CRT-D device.

Ventricular Tachycardia Catheter Ablation: Retrospective Analysis and Prospective Outlooks-A Comprehensive Review

Ventricular tachycardia is a potentially life-threatening arrhythmia associated with an overall high morbi-mortality, particularly in patients with structural heart disease. Despite their pivotal role in preventing sudden cardiac death, implantable cardioverter-defibrillators, although a guideline-based class I recommendation, are unable to prevent arrhythmic episodes and significantly alter the quality of life by delivering recurrent therapies. From open-heart surgical ablation to the currently widely used percutaneous approach, catheter ablation is a safe and effective procedure able to target the responsible re-entry myocardial circuit from both the endocardium and the epicardium. There are four main mapping strategies, activation, entrainment, pace, and substrate mapping, each of them with their own advantages and limitations. The contemporary guideline-based recommendations for VT ablation primarily apply to patients experiencing antiarrhythmic drug ineffectiveness or those intolerant to the pharmacological treatment. Although highly effective in most cases of scar-related VTs, the traditional approach may sometimes be insufficient, especially in patients with nonischemic cardiomyopathies, where circuits may be unmappable using the classic techniques. Alternative methods have been proposed, such as stereotactic arrhythmia radioablation or radiotherapy ablation, surgical ablation, needle ablation, transarterial coronary ethanol ablation, and retrograde coronary venous ethanol ablation, with promising results. Further studies are needed in order to prove the overall efficacy of these methods in comparison to standard radiofrequency delivery. Nevertheless, as the field of cardiac electrophysiology continues to evolve, it is important to acknowledge the role of artificial intelligence in both the pre-procedural planning and the intervention itself.

Statins-Beyond Their Use in Hypercholesterolemia: Focus on the Pediatric Population

Statins are a class of medications primarily used in adults to lower cholesterol levels and reduce the risk of cardiovascular events. However, the use of statins in children is generally limited and carefully considered despite the well-documented anti-inflammatory, anti-angiogenic, and pro-apoptotic effects, as well as their effect on cell signaling pathways. These multifaceted effects, known as pleiotropic effects, encompass enhancements in endothelial function, a significant reduction in oxidative stress, the stabilization of atherosclerotic plaques, immunomodulation, the inhibition of vascular smooth muscle proliferation, an influence on bone metabolism, anti-inflammatory properties, antithrombotic effects, and a diminished risk of dementia. In children, recent research revealed promising perspectives on the use of statins in various conditions including neurological, cardiovascular, and oncologic diseases, as well as special situations, such as transplanted children. The long-term safety and efficacy of statins in children are still subjects of ongoing research, and healthcare providers carefully assess the individual risk factors and benefits before prescribing these medications to pediatric patients. The use of statins in children is generally less common than in adults, and it requires close monitoring and supervision by healthcare professionals. Further research is needed to fully assess the pleiotropic effects of statins in the pediatric population.

Nanotechnology Innovations in Pediatric Cardiology and Cardiovascular Medicine: A Comprehensive Review

(1) Background: Nanomedicine, incorporating various nanoparticles and nanomaterials, offers significant potential in medical practice. Its clinical adoption, however, faces challenges like safety concerns, regulatory hurdles, and biocompatibility issues. Despite these, recent advancements have led to the approval of many nanotechnology-based products, including those for pediatric use. (2) Methods: Our approach included reviewing clinical, preclinical, and animal studies, as well as literature reviews from the past two decades and ongoing trials. (3) Results: Nanotechnology has introduced innovative solutions in cardiovascular care, particularly in managing myocardial ischemia. Key developments include drug-eluting stents, nitric oxide-releasing coatings, and the use of magnetic nanoparticles in cardiomyocyte transplantation. These advancements are pivotal for early detection and treatment. In cardiovascular imaging, nanotechnology enables noninvasive assessments. In pediatric cardiology, it holds promise in assisting the development of biological conduits, synthetic valves, and bioartificial grafts for congenital heart defects, and offers new treatments for conditions like dilated cardiomyopathy and pulmonary hypertension. (4) Conclusions: Nanomedicine presents groundbreaking solutions for cardiovascular diseases in both adults and children. It has the potential to transform cardiac care, from enhancing myocardial ischemia treatment and imaging techniques to addressing congenital heart issues. Further research and guideline development are crucial for optimizing its clinical application and revolutionizing patient care.

Feasibility of Conduction System Pacing in Patients with Baseline Bundle Branch Block-A Single-Center Mid-Term Follow-Up Study

BACKGROUND

The primary prerequisite for a successful conduction system pacing (CSP) procedure is the integrity of the conduction system, which may be impaired if a baseline bundle branch block (BBB) is present. This study aimed to evaluate the feasibility and mid-term performance of permanent CSP in patients with baseline BBB and to compare the results between left bundle branch block (LBBB) and right bundle branch block (RBBB) patterns.

MATERIAL AND METHODS

A total of 101 patients with typical BBB and an attempt at CSP were retrospectively reviewed. Procedural characteristics, pacing, sensing parameters, and complications at baseline and after a mid-term follow-up were analyzed.

RESULTS

The global procedural success for CSP was 93%. His bundle pacing (HBP) had a significantly lower success rate than left bundle branch area pacing (LBBAP) (50.5% vs. 86%). The paced QRS duration was significantly narrower with HBP. The pacing and sensing thresholds were significantly better with LBBAP. Procedural complications occurred only in the LBBAP group (two acute perforations in the LV cavity and one acute chest pain during lead fixation) without long-term sequelae. The HBP and the LBBAP procedural success rates were higher in the RBBB versus the LBBB group (62.5% vs. 44.9% and 100% vs. 81.5%, respectively). Baseline QRS duration, atrial volumes, and right ventricular diameters were significantly associated with HBP procedural failure. The follow-up pacing and sensing thresholds were similar to the baseline values for all pacing methods and BBB morphology. Only one device-related complication leading to pacing interruption was recorded.

CONCLUSION

In patients with bundle branch blocks, CSP is a feasible procedure associated with a high success rate, stable pacing and sensing parameters, and low complication rates over a mid-term follow-up.

Arrhythmogenic Right Ventricular Cardiomyopathy in Children: A Systematic Review

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited disease characterized by the progressive replacement of the normal myocardium by fibroadipocytic tissue. The importance of an early diagnosis is supported by a higher risk of sudden cardiac death in the pediatric population. We reviewed the literature on diagnosis, risk stratification, and prognosis in the pediatric population with ARVC. In case reports which analyzed children with ARVC, the most common sign was ventricular tachycardia, frequently presenting as dizziness, syncope, or even cardiac arrest. Currently, there is no gold standard for diagnosing ARVC in children. Nevertheless, genetic analysis may provide a proper diagnosis tool for asymptomatic cases. Although risk stratification is recommended in patients with ARVC, a validated prediction model for risk stratification in children is still lacking; thus, it is a matter of further research. In consequence, even though ARVC is a relatively rare condition in children, it negatively impacts the survival and clinical outcomes of the patients. Therefore, appropriate and validated diagnostic and risk stratification tools are crucial for the early detection of children with ARVC, ensuring a prompt therapeutic intervention.

Can Artificial Intelligence Revolutionize the Diagnosis and Management of the Atrial Septal Defect in Children?

Atrial septal defects (ASDs) present a significant healthcare challenge, demanding accurate and timely diagnosis and precise management to ensure optimal patient outcomes. Artificial intelligence (AI) applications in healthcare are rapidly evolving, offering promise for enhanced medical decision-making and patient care. In the context of cardiology, the integration of AI promises to provide more efficient and accurate diagnosis and personalized treatment strategies for ASD patients. In interventional cardiology, sometimes the lack of precise measurement of the cardiac rims evaluated by transthoracic echocardiography combined with the floppy aspect of the rims can mislead and result in complications. AI software can be created to generate responses for difficult tasks, like which device is the most suitable for different shapes and dimensions to prevent embolization or erosion. This paper reviews the current state of AI in healthcare and its applications in cardiology, emphasizing the specific opportunities and challenges in applying AI to ASD diagnosis and management. By exploring the capabilities and limitations of AI in ASD diagnosis and management. This paper highlights the evolution of medical practice towards a more AI-augmented future, demonstrating the capacity of AI to unlock new possibilities for healthcare professionals and patients alike.

Arrhythmic Risk and Treatment after Transcatheter Atrial Septal Defect Closure

Atrial septal defect (ASD) represents the most common congenital heart defect identified in adulthood. Atrial and ventricular geometric remodeling due to intracardiac shunt increase the risk of arrhythmias, especially atrial fibrillation (AF). Clinical, echocardiography, electrocardiogram, and device-related predictors may be used to assess the risk of atrial arrhythmias after ASD closure. The underlying mechanisms in these patients are complex and at least in part independent of the structural remodeling secondary to hemodynamic overload. Device closure of the ASD itself and its timing impact future arrhythmia risk, as well as posing a challenge for when transseptal puncture is required. Sudden cardiac death (SCD) risk is higher than in the general population and an implantable cardioverter-defibrillator (ICD) may be indicated in selected cases.

Optimal Cardiac Resynchronization Therapy with Conduction System Pacing Guided by Electro-Anatomical Mapping: A Case Report

INTRODUCTION

Biventricular pacing has been the gold standard for cardiac resynchronization therapy in patients with left bundle branch block and severely reduced left ventricular ejection fraction for decades. However, in the past few years, this role has been challenged by the promising results of conduction system pacing in these patients, which has proven non-inferior and, at times, superior to biventricular pacing regarding left ventricular function outcomes. One of the most important limitations of both procedures is the long fluoroscopy times.

CASE DESCRIPTION

We present the case of a 60-year-old patient with non-ischemic dilated cardiomyopathy and left bundle branch block in whom conduction system pacing was chosen as the first option for resynchronization therapy. A 3D electro-anatomical mapping system was used to guide the lead to the His bundle region, where correction was observed at high amplitudes, and afterward to the optimal septal penetration site. After reaching the left endocardium, left bundle branch pacing achieved a narrow, paced QRS complex with low fluoroscopy exposure. The three-month follow-up showed a significant improvement in clinical status and left ventricular function.

CONCLUSION

Since conduction system pacing requires a great deal of precision, targeting specific, narrow structures inside the heart, 3D mapping is a valuable tool that increases the chances of success, especially in patients with complex anatomies, such as those with indications for cardiac resynchronization therapy.

Autoinflammatory Recurrent Pericarditis Associated with a New NLRP12 Mutation in a Male Adolescent

Idiopathic recurrent pericarditis (IRP) can be the hallmark of an autoinflammatory syndrome with recurrent attacks of chest pain and symptom-free intervals following an acute episode. The recurrence rate may be 35% in the pediatric population, frequently with less severe manifestations than at the first episode. Pericarditis can be the sole clinical manifestation or may be part of a systemic autoinflammatory disease (SAID), especially in the case of a recurrence. Familial Mediterranean Fever (FMF), Tumor Necrosis Factor Receptor-Associated Periodic Syndrome (TRAPS), Mevalonate-Kinase Deficiency (MKD), nucleotide-binding oligomerization domain 2 (NOD2)-associated autoinflammatory syndrome, and others are closely related to IRP based on similar clinical manifestations and treatment responses to anti-interleukin 1 (IL-1) agents, such as anakinra, and should therefore be excluded in patients with IRP. A newly described SAID, an autosomal dominant disorder known as NLRP12-AID (nucleotide-binding leucine-rich repeat-containing receptor 12-related autoinflammatory disease) is caused by heterozygous mutations in the NLRP12 gene and most commonly affects children. Fewer than 40 pediatric patients with NLRP12-AID have been described in the medical literature, with none presenting with RP. We report a case of relapsing pericarditis responsive to anti-IL-1 therapy in a male adolescent who carried a missense mutation in the NLRP12 gene potentially causative of the excessive activation of inflammatory pathways. This is a unique case in the medical literature that associates recurrent pericarditis in an adolescent presumed to be related to the missense mutation in the NLRP12 gene. The role of the NLRP12 inflammasome in generating and maintaining recurrent pericardial inflammation should be considered.

Non-revascularized chronic total occlusions impact on substrate and post-ablation results in drug-refractory electrical storm

Background and aims

There is limited data concerning the effect of non-revascularized chronic total occlusions (NR-CTOs) after VT ablation. This study sought to evaluate the impact of NR-CTOs after ablation for electrical storm (ES).

Methods

Post-hoc retrospective analysis of data regarding 64 consecutive post-myocardial infarction patients (out of which 12 patients with NR-CTOs and 52 without NR-CTOs) undergoing substrate ablation for ES with an available median follow-up of 37.53 (7.25-64.65) months. Ablation result was assessed by inducibility of sustained monomorphic VT (SMVT) during final programmed ventricular stimulation (PVS). The primary endpoints were all-cause mortality and VT/VF recurrences after ablation, respectively, stratified by the presence of NR-CTOs. The secondary endpoint was to assess the predictive effect of NR-CTOs on all-cause mortality and VT/VF recurrences in relation to other relevant prognostic factors.

Results

At baseline, the presence of NR-CTOs was associated with higher bipolar BZ-to-total scar ratio (72.4% ± 17.9% vs. 52% ± 37.7%, p = 0.022) and more failure to eliminate the clinical VT (25% (3) vs. 0% (0), p < 0.001). During follow-up, overall all-cause mortality and recurrences were more frequent in the NR-CTO subgroup (75% (9) vs. 19.2% (10), log rank p = 0.003 and 58.3% vs. 23.1% (12), log rank p = 0.042 respectively). After adjusting for end-procedural residual SMVT inducibility, NR-CTOs predicted death during follow-up (HR 3.380, p = 0.009) however not recurrence (HR 1.986, p = 0.154).

Conclusions

NR-CTO patients treated by RFCA for drug-refractory ES demonstrated a higher ratio of BZ-to-total-scar area. In this analysis, NR-CTO was associated with worse acute procedural results and may as well impact long-term outcomes which should be further assessed in larger patient populations.

Transvenous Lead Extraction of Cardiac Implantable Electronic Devices: Reimplant Strategy and Outcomes in a Single-Center Experience

Cardiac implantable electronic devices are now widely used worldwide and the numbers are increasing exponentially. Subsequently, long-term complications have increased. Transvenous lead-extraction (TLE) is the gold standard for removing infected devices, treating systemic device-related infections including endocarditis, and removing devices for other non-infectious complications. Most patients still require device therapy after TLE for several indications, including lifesaving defibrillation or pacing in pacemaker-dependent patients. The decision to reimplant is challenging, particularly when the primary cause for device removal includes device-related infections and patients frequently are pacemaker dependent. We aim to present our strategy for reimplanting after performing TLE in 88 consecutive patients. We performed transvenous removal of 150 pacemaker and defibrillator leads, of which 74% for local or systemic infection. We report a 99.3% clinical success after TLE. Out of 88 patients who had undergone TLE and after reanalysing the device indication, 67 patients (76%) still had indication for device removal, but three of them refused to undergo reimplant and 58 were re-implanted. Of the re-implanted patients, 58.6% were implanted on the contra-lateral side, 38% on the ipsilateral side and two patients who had been previously implanted with ICD were reimplanted with a subcutaneous implantable cardioverter defibrillator (S-ICD). Up to 34.4% of patients were re-implanted during the same TLE procedure, which was performed for device up-grade in patients with venous occlusion, 24% were implanted during the same hospital admission for TLE but not during TLE, and 41.3% were discharged and reimplanted afterwards. With this strategy for reimplantation, we report no re-infections and no device-removal-related arrhythmic major events or deaths during one-year follow-up. In conclusion, most patients still require device therapy after TLE. In patients with previous infection of the device, the reimplantation strategy should be carefully analyzed to prevent infection relapse and limit the consequences of the absence of the device.

Infective Endocarditis among Pediatric Patients with Prosthetic Valves and Cardiac Devices: A Review and Update of Recent Emerging Diagnostic and Management Strategies

Infective endocarditis (IE) is a disease of the endocardium, which leads to the appearance of vegetation on the valves, cardiac structures, or, potentially, vascular endothelium of the heart. The risk of IE can be increased more than 140 times by congenital heart disease (50-59% of all IE), particularly if cyanotic. An increase in mortality may result from IE in patients with a complex cardiac pathology or patients with an implanted prosthetic material, most frequently conduits in a pulmonary position. Cardiac implantable electronic devices (CIED) infective endocarditis is a life-threatening complication representing 10% of all cases of endocarditis. Common signs of presentation are often fever and chills; redness and swelling at the pocket of the pacemaker, including the erosion and exteriorization of the device; and life-threatening sepsis. The use of intracardiac echocardiography for the diagnosis of IE is an innovative method. This may be needed, especially in older children undergoing complex cardiac surgery, when transthoracic echocardiography (TTE) and transesophageal echocardiography (TOE) failed to provide a reliable diagnosis. The 2018 European Heart Rhythm Association (EHRA) experts' consensus statement on transvenous lead extraction recommends complete device removal and antimicrobial therapy for any device-related infection, including CIED-IE. The most detected microorganism was Staphylococcus Aureus. In addition, cardiac surgery and interventional cardiology associated with the placement of prostheses or conduits may increase the risk of IE up to 1.6% for Melody valve implantation. Our manuscript presents a comprehensive review of infective endocarditis associated with cardiac devices and prostheses in the pediatric population, including recent advances in diagnosis and management.

Not Just a One-Way: Mahaim Accessory Pathway Concomitantly Supporting Orthodromic Atrioventricular Re-Entrant Tachycardia

INTRODUCTION

We report the case of a 41-year-old female with documented narrow QRS tachycardia. During electrophysiological study, both orthodromic and antidromic atrioventricular reentry tachycardia (AVRT) were demonstrated as well as short episodes of pre-excited atrial fibrillation. Programmed atrial stimulation resulted in decremental anterograde conduction on the AP, thus confirming an unexpected Mahaim accessory pathway (AP) diagnosis.

DISCUSSION

Limited 3D activation maps of the right atrium during orthoAVRT, respectively, and the right ventricle (RV) during antiAVRT were constructed and helped accurately describe the atrial and ventricular insertion points, which were superposed on the tricuspid ring, confirming the existence of a single short atrio-ventricular right free wall AP. Short atrioventricular APs with anterograde Mahaim-type conduction concomitantly sustaining orthodromic AVRT are extremely rare.

CONCLUSIONS

Electroanatomical 3D mapping may help both to clarify the diagnosis and increase the success rate by accurately describing the insertion points of complex accessory pathways.

Three-dimensional left and right atrioventricular coupling indices as prognostic markers in heart failure with reduced ejection fraction

Background

While left atrial and left ventricular functional parameters are established prognostic markers in heart failure (HF), recent studies suggest that parameters assessing the atrio-ventricular interaction are better predictors. Left atrioventricular coupling index (LACI) assessed with cardiac magnetic resonance is an emerging outcome predictor in HF patients, however its assessment by three-dimensional (3D) echocardiography hasn't been studied so far. Moreover, the role of the right atrioventricular coupling index (RACI) in HF remains to be established.

Purpose

We sought to evaluate the LACI, RACI and combined left and right atrioventricular coupling index (CACI) with 3D echocardiography in a cohort of patients with HF and reduced ejection fraction (HFrEF) and to assess their prognostic role.

Methods

We prospectively enrolled 60 consecutive patients with HFrEF in sinus rhythm, who underwent two dimensional and 3D echocardiographic acquisitions. LACI was calculated as the ratio between 3D left atrial and 3D left ventricular end-diastolic volumes. RACI was calculated as the ratio between 3D right atrial and 3D right ventricular end-diastolic volumes. CACI was defined as the sum between LACI and RACI. Patients were followed for major adverse cardiac events (MACE), defined as a composite endpoint of cardiac death or HF decompensation requiring hospitalization.

Results

After a mean follow-up of 19±9 months, 33 patients reached the endpoint. Patients with MACE had higher LACI (33.5±21.1% vs. 19.9±12.4%, p=0.003), higher RACI (33.6±23.6% vs. 20.8±13.8%, p=0.01) and higher CACI (67.0±38.0% vs. 40.7±24.4%, p=0.002) – suggestive of atrioventricular decoupling. In ROC analysis, CACI had the best AUC for event prediction (AUC=0.750, p=0.001, cut-off=42.8%, Sen=69.7%, Spe=77.7%), followed by LACI (AUC=0.745, p=0.001, cut-off=20.4%, Sen=72.7%, Spe=70.4%), and then RACI (AUC=0.717, p=0.004, cut-off=18.6%, Sen=75.8%, Spe=70.4%).

In unadjusted Cox regression, all three atrioventricular coupling indices were predictors of MACE: HR=3.30 [95% CI, 1.52–7.14], p=0.002 for LACI, HR=4.54 [95% CI, 2.03–10.17], p&lt;0.001 for RACI, HR=3.87 [95% CI, 1.82–8.23], p&lt;0.001 for CACI. A multivariable model was constructed using well-established event predictors in HFrEF: age, global longitudinal strain of the left ventricle, global longitudinal strain of the right ventricular free wall and pulmonary artery systolic pressure. All three atrioventricular coupling indices remained independent predictors of MACE in multivariable regression: HR=3.11 [95% CI, 1.36–7.14], p=0.007 for LACI, HR=4.38 [95% CI, 1.84–10.41], p=0.001 for RACI, HR=3.98 [95% CI, 1.75–9.03], p=0.001 for CACI.

Conclusion

Greater 3D LACI, RACI and CACI, reflecting atrioventricular uncoupling, are all independent prognostic markers in HFrEF.

Funding Acknowledgement

Type of funding sources: None.

Combined left and right atrial stiffness index as an independent predictor of rehospitalization in dilated cardiomyopathy

Background

Left atrial stiffness index (LASI) derived from speckle-tracking echocardiography (STE) is a marker of pressure transfer to the pulmonary circulation and a predictor of symptoms in patients with heart failure (HF). However, the role of the right atrial stiffness index (RASI) in the setting of left-sided HF is incompletely understood.

Purpose

We sought to evaluate the left, right and combined bi-atrial stiffness index (BASI) in a cohort of patients with dilated cardiomyopathy (DCM) and to assess their prognostic role.

Methods

We prospectively enrolled 60 consecutive patients with DCM in sinus rhythm, who underwent transthoracic echocardiography. As previously described, LASI was defined as the ratio between early diastolic transmitral flow velocity/lateral mitral annulus myocardial velocity (E/e') and left atrial reservoir strain derived from STE. RASI was defined as the ratio between early diastolic tricuspid flow velocity/lateral tricuspid annulus myocardial velocity (Et/e't) and right atrial reservoir strain. BASI was defined as the sum of LASI and RASI. Patients were followed for 19±9 months for an endpoint of HF decompensation requiring hospitalization.

Results

29 patients reached the endpoint. Patients with rehospitalization had higher LASI (2.50±2.15 vs. 1.23±1.61, p=0.01), higher RASI (0.76±0.77 vs. 0.36±0.41, p=0.02) and higher BASI (3.25±2.65 vs. 1.59±1.71, p=0.006). In univariate Cox regression, all three stiffness indices were predictors of adverse outcome: HR=2.63 [95% CI, 1.22–5.66], p=0.014 for LASI, HR=2.86 [95% CI, 1.26–6.48], p=0.012 for RASI, HR=3.49 [95% CI, 1.49–8.20], p=0.004 for BASI. A multivariable model was constructed using well-established event predictors in DCM. After adjustment for age, left ventricular ejection fraction and indexed maximal left atrial volume, BASI was the only stiffness index that remained an independent predictor of rehospitalization for HF: HR=2.76 [95% CI, 1.08–7.03], p=0.03. In ROC analysis, a BASI greater than 1.25 had a 75.9% sensitivity and 64.5% specificity for event prediction (AUC=0.716, p=0.004).

Conclusion

Stiffness of both atria is significantly greater in patients with DCM who get hospitalized for HF decompensation. Combining the left and right atrial stiffness indices provides a better prognostic stratification than left or right atrial stiffness alone, since BASI was the only stiffness index that remained an independent predictor of rehospitalization after adjustment for confounders.

Funding Acknowledgement

Type of funding sources: None.

Mechanisms, time course and predictability of premature ventricular contractions cardiomyopathy-an update on its development and resolution

Frequent premature ventricular contractions (PVCs) associated left ventricular systolic dysfunction (LVSD) is a well-known clinical scenario and numerous predictors for cardiomyopathy (CMP) development have been already thoroughly described. It may present as a "pure" form of dissynchrony-induced cardiomyopathy or it may be an aggravating component of a multifactorial structural heart disease. However, the precise risk to develop PVC-induced CMP (which would allow for tailored-patient monitoring and/or early treatment) and the degree of CMP reversibility after PVC suppression/elimination (which may permit appropriate candidate selection for therapy) are unclear. Moreover, there is limited data regarding the time course of CMP development and resolution after arrhythmia suppression. Even less known are the other components of PVC-induced CMP, such as right ventricular (RV) and atrial myopathies. This review targets to synthetize the most recent information in this regard and bring a deeper understanding of this heart failure scenario. The mechanisms, time course (both in experimental models and clinical experiences) and predictors of reverse-remodelling after arrhythmia suppression are described. The novel experience hereby presented may aid everyday clinical practice, promoting a new paradigm involving more complex, multi-level and multi-modality evaluation and possible earlier intervention at least in some patient subsets.

Nonischemic Super-Responders in Fusion CRT Pacing with Normal Atrioventricular Conduction

Background: Fusion CRT pacing (FCRT) is noninferior to biventricular pacing, according to the current data. The aim of this study is to assess the response to FCRT and to identify predictors of super-responders (SRs) in a nonischemic population with normal AV conduction. Methods: LV-only CRT patients (pts) with a right atrium/left ventricle pacing system implanted in two CRT centers in Romania were included. Device interrogation, exercise tests, echocardiography, and individualized drug optimization were performed every 6 months during close follow-up. SRs pts were defined as those with left ventricular end-systolic volume (LVESV) improvement ≥30% and stable ejection fraction (LVEF) ≥45%. Results: A total of 25 out of 83 pts (31%) were SRs, with nonischemic LBBB low EF cardiomyopathy (50 male, 62 ± 9 y.o.) initially included. Mean follow-up was 5 years ± 27 months. Patients were divided in two groups: SRs and non-SRs (52 responders/6 hypo-responders). Two predictors were found in the SRs group: a higher baseline LVEF (SRs 29 ± 5% vs. non-SRs 26 ± 5%, p = 0.02) and a lower pulmonary arterial systolic pressure (SRs 38 ± 11 mm Hg vs. non-SRs 50 ± 15 mmHg, p = 0.003). Baseline severe mitral regurgitation was found in 11% of SRs vs. 64% in the non-SRs group. Conclusions: SRs in the selected NICM-FCRT group are significative high. Higher baseline LVEF and mild pulmonary arterial hypertension were independently associated with super-response.

Ratio between Right Ventricular Longitudinal Strain and Pulmonary Arterial Systolic Pressure: Novel Prognostic Parameter in Patients Undergoing Cardiac Resynchronization Therapy

BACKGROUND

We aimed to evaluate whether right ventricle (RV) longitudinal strain indexed to pulmonary arterial systolic pressure (PASP) has prognostic significance in patients undergoing cardiac resynchronization therapy (CRT).

METHODS

Patients undergoing CRT were prospectively included. The primary endpoint was adverse cardiovascular events (death and HF-related hospitalizations). RV global longitudinal strain (RVGLS) and RV free wall strain (RVfwS) were measured by speckle tracking and indexed to echocardiographic estimated PASP.

RESULTS

A total of 54 patients (64.0 ± 13.8 years; 58% male) were included. After 33 ± 12.9 months, the primary endpoint occurred in 18 patients. Baseline RVGLS/PASP and RVfwS/PASP showed good discriminative ability for response to CRT (AUC = 0.88, 95% CI (0.74-1) and AUC = 0.87, 95% CI (0.77-1)). RVGLS/PASP and RVfwS/PASP were significantly associated with high risk of events at univariate analysis (HR 0.039, 95% CI (0.001-0.8) p < 0.05, respectively HR = 0.049, 95% CI (0.0033-0.72), p < 0.05). Upon multivariate Cox regression analysis, RVGLS/PASP and RVfwS/PASP remained associated with high risk of events (HR 0.018, 95% CI (0.0005-0.64), p = 0.02 and HR 0.015, 95% CI (0.0004-0.524), p = 0.01) after correction for gender, etiology, QRS duration and morphology. Conclusions: Indexing RV longitudinal strain (global and free wall) by PASP provides a parameter, which independently identifies patients with high risk of cardiovascular events and predicts non-response to CRT.

Right ventricular-arterial coupling - A new perspective for right ventricle evaluation in heart failure patients undergoing cardiac resynchronization therapy

BACKGROUND

Right ventricular - arterial (RV-PA) coupling can be estimated by echocardiography using the ratio between (TAPSE) and pulmonary arterial systolic pressure (PASP). TAPSE/PASP ratio proved to be a prognostic parameter in patients with heart failure and reduced ejection fraction (HFrEF).

OBJECTIVE

To evaluate the significance of RV-PA coupling in patients with HFrEF undergoing cardiac resynchronization therapy (CRT).

METHODS

Patients undergoing CRT in our center between January 2017 and November 2019 were eligible. Response to CRT was defined by a reduction of more than 15% of left ventricle systolic volume (LVESV) one year after CRT. Primary endpoint was a composite of HF hospitalizations and death during follow-up.

RESULTS

54 patients (Age 64.0 ± 13.8 years; 58% male; left ventricular ejection fraction (LVEF) 28.4 ± 1.3%) were prospectively included. After a mean follow-up of 31 ± 12.9months, the primary endpoint had occurred in 18 (33.3%) patients. A lower TAPSE/PASP ratio was associated with baseline worse HF symptoms, lower LVEF and long-term less LV reverse remodeling (P < .05). After one year CRT improved RV systolic function (TAPSE, RV global longitudinal strain, P < .05), but not TAPSE/PASP ratio (P = .4). The ratio TAPSE/PASP (AUC=0.834) ≥ 0.58 mm/mm Hg showed good sensitivity (90%) and specificity (81.8%) for predicting response to CRT while a ratio <0.58 mm/mm Hg was associated with a higher risk of death and HF hospitalizations during the follow-up (HR 5.37 95%CI [1.6-18], P < .001).

CONCLUSION

RV-PA coupling evaluation using TAPSE/PASP ratio predicts CRT response. A lower TAPSE/PASP ratio is associated with a higher risk of adverse cardiovascular events.

Premature ventricular complex site of origin and ablation outcomes in patients with prior myocardial infarction

BACKGROUND

Frequent premature ventricular complexes (PVCs) are common after a myocardial infarction (MI), but data on PVC ablation in this population are limited.

OBJECTIVE

The purpose of this study was to analyze data on PVC ablation in post-MI patients.

METHODS

Three hundred thirty-two patients with frequent PVCs and left ventricular (LV) dysfunction were prospectively studied. Data from 67 patients (20%; age 63 ± 10 years; 65 men [93%]) with previous MI were compared with the remaining 265 patients.

RESULTS

PVCs in post-MI patients originate predominantly from the LV (92% LV vs 6% right ventricle [RV]; P <.001). The most frequent sites of origin (SOO) were MI scar in 23 patients (34%) and left ventricular outflow tract (LVOT) in 22 patients (33%). A papillary muscle origin was more frequent in post-MI patients (16% vs 4%; P = .001), whereas an RV outflow tract origin was less frequent (1% vs 33%; P <.001) compared to patients without MI. In post-MI patients, PVC burden decreased from 29% ± 12% at baseline to 4.6% ± 7% (P <.001); left ventricular ejection fraction (LVEF) improved from 33.6% ± 8% to 42% ± 10% (P <.001); and New York Heart Association functional class improved from 2.1 ± 0.7 to 1.4 ± 0.5 points (P <.001) at 12 months. Compared with the remaining 265 patients, there were no differences in acute ablation success (85% vs 85%; P = .45), complication rate (6% vs 6%; P = .41), or absolute improvement in LVEF (8.8 ± 10 vs 9.9 ± 11 absolute points; P = .38).

CONCLUSION

PVC ablation significantly improves cardiac function and functional status in post-MI patients. PVCs predominantly originate from MI scar and LVOT. A papillary muscle SOO was found to be strongly associated with previous MI.

Influence of baseline QRS on the left ventricular ejection fraction recovery after frequent premature ventricular complex ablation

Aims

Frequent premature ventricular complexes (PVCs) can induce or worsen left ventricular systolic dysfunction. We aimed to investigate the influence of the baseline QRS in the response after PVC ablation in patients with depressed left ventricular ejection fraction (LVEF).

Methods and results

Two hundred and fifteen [59 ± 13 years old, 152 (71%) men] consecutive patients with left ventricular (LV) systolic dysfunction and frequent PVCs referred for ablation were included and followed-up for 12 months. Echocardiographic response was defined as an improvement of at least five absolute points in LVEF. Clinical, electrocardiogram, and electrophysiological characteristics were analysed. Mean baseline QRS duration was 110 ms [97–140]. Premature ventricular complex burden significantly decreased after ablation from 23% [16–33] at baseline to 1% [0–8] at 12 months, P &lt; 0.001. Mean PVC burden reduction was 18 [8–30] points. There was a significant improvement of LVEF from 35% [29–40] at baseline to 44% [35–55] at 12 months, P &lt; 0.001. One hundred and thirty (61%) patients were considered as echocardiographic responders. Baseline QRS duration (ms) [odds ratio (OR) 0.98 (0.97–0.99), P = 0.01] was an independent predictor of echocardiographic response. Mean LVEF improvement was 16 [10–21] points when the baseline QRS duration was &lt;90 ms; 12 [4–20] when it was 90–110 ms; 5 [0–15] when it was 110 ± 130 ms; and 0 [0–6] points when it was &gt;130 ms.

Conclusions

In patients with LV systolic dysfunction, intrinsic QRS duration is inversely related to the probability and the degree of echocardiographic response after frequent PVC ablation. Patients with a QRS duration &gt;130 ms at baseline have the poorer response after ablation.

P888 How many diagnoses can one heart gather?

Purpose

We present the case of a 76 years old patient with multiple cardiovascular risk factors (hypertension, dyslipidemia, obesity, former smoker) with history of unprovoked pulmonary embolism - PE (2018), without evidence of deep venous thrombosis, in treatment with rivaroxaban, who presented with worsening severe dyspnea at effort and peripheral edemas, symptoms started a few days before admission. He denied angina or palpitations.

Methods

On clinical examination we identified obesity grade II and bilateral leg edema and routine laboratory tests revealed controlled dyslipidemia. The electrocardiogram (ECG) showed atrial flutter (AF) with block 5:1, heart rate 50/min, with negative T waves in DI, aVL and V2-V6. Transthoracic echocardiography with contrast was performed showing no wall motion abnormalities otherwise with a mild concentric left ventricle hypertrophy (LVH) except for the apex where there was severe LVH suggestive for AHCM; there was an increased aortic velocity with an aortic valve with degenerative changes. We thought that the changes on the ECG were most likely due to AHCM. A thoracic tomography scan with contrast was also performed because of associated dyspnea which excluded an acute recurrence of PE. The next day the T waves on ECG normalized, putting forward for consideration an acute coronary syndrome. We performed a coronarography which confirmed a 80% stenosis of proximal left anterior descending (LAD) artery with subsequent placement of a drug eluting stent. We also did a transesophageal echocardiography (noncompliant patient) for exclusion of intracardiac thrombi (which also showed bicuspid aortic valve) and then we performed radiofrequency ablation of the cavotricuspid isthmus followed by atrial overdrive pacing for typical AF, but unsuccessful, with degeneration into atrial fibrillation.

Results

Sometimes heart failure might occur due to multiple etiological factors and mechanisms of decompensation. We had a patient with AHCM with an ECG that could be interpreted as typical for this pathology but with concomitent severely affected LAD coronary artery, with AF and high grade atrioventricular block plus mild aortic stenosis with a bicuspid aortic valve with indication for strict follow up.

Conclusions

AHCM was first described in Japan where has the highest prevalence, but is also documented in other countries (rare in Caucasian population). Note that AHCM often mimic acute coronary syndromes through clinical manifestations and electrocardiographic aspects. Our case report showed a Caucasian patient with AHCM with concomitent severe atherosclerotic desease and aortic stenosis on a bicuspid valve.

P898 Role and evolution of the right ventricle in heart failure patients treated with cardiac resynchronization therapy delivered by left ventricle pacing alone

Funding Acknowledgements

This work was supported by CREDO Project - ID: 49182, financed through the SOP IEC -A2-0.2.2.1-2013-1 cofinanced by the ERDF.

Background

Cardiac resynchronization therapy (CRT) is an effective treatment for patients with heart failure (HF) with reduced ejection fraction. Biventricular pacing is the most common mode of delivering CRT. However, several studies have demonstrated non-inferiority of LV pacing alone. There are several trials about the role and evolution of right ventricle (RV) systolic function in CRT patients delivered by biventricular pacing showing that RV function is an independent predictor of long-term outcome following CRT, and improvement in RV function after CRT.

Purpose

To examine if RV function and dimensions prior to CRT could have an impact on CRT response and assessment of the evolution of RV function after 1 year follow up in patients with LV pacing alone.

Methods

22 patients with a mean age of 63 ± 10.6 years including 9 (40,9%) females and 13 man (59,1%), with HF (EF &lt; 35%, LBBB &gt; 120 ms, or non-LBBB &gt; 150 ms, with NYHA II to IV) were enrolled and underwent CRT implantation LV pacing alone . Each patient benefited from standard two dimensional (2D) echocardiography, tissue Doppler imaging, with assessment of Left ventricular (LV) end-diastolic (LVEDV), and end-systolic volumes (LVESV), ejection fraction, RV maximum basal (RVD basal), TAPSE, fractional area change (FAC), and tricuspid lateral annular systolic velocity (S′) , RV TEI index , RV systolic pressure using Bernoulli equation, at inclusion before CRT and 12 ± 2 months after CRT implantation. Patients presenting with reductions of LVESV of &gt;15% were termed volumetric responders for further statistical analysis and patients with reduction of NYHA class were termed clinical responders.

Results

14 patients (63.63 %) cases were volumetric responders and 21 patients were clinical responders showing an improvement in NYHA class at one year. 1 patient died. Among echocardiographic parameters of RV: RVD basal , TAPSE , FAC , TEI index, RV systolic pressure (p &lt; 0.01) were good predictors for volumetric response proving that a dilated RV with poor systolic function may be a predictor for non response to CRT even in patients with LV alone pacing. TAPSE and FAC have the best AUC for prediction of response to CRT therapy.We proposed cutoff values for predicting response versus non response to CRT therapy TAPSE 16.6mm (AUC 0.827, 95% CI, p &lt; 0.05, sensibility 100%, specificity 71.4% ) and FAC 36% (AUC 0.826, 95%CI, p &lt; 0.05, specificity 91%, sensibility 66%) and RVD basal 37,5mm (AUC 0.805, 95%CI, p = 0.03, sensibility 63%, specificty 85%). In volumetric non-responders, RV function improves at one year follow up with an increase in TAPSE (p = 0.008) and a decrease of RV TEI index (p = 0.04).

Conclusions

LV pacing alone CRT improves RV systolic function and may account for clinical benefit in patients without LV function improvement at one year follow-up. RV systolic function and dimensions before CRT implantation could predict response to LV pacing alone CRT therapy.

Clinical implementation of cardiac resynchronization therapy-regional disparities across selected ESC member countries

Background

The present analysis aimed to estimate the penetration of cardiac resynchronization therapy (CRT) on the basis of the prevalence and incidence of eligible patients in selected European countries and in Israel.

Methods and Results

The following countries were considered: Italy, Slovakia, Greece, Israel, Slovenia, Serbia, the Czech Republic, Poland, Romania, Hungary, Ukraine, and the Russian Federation. CRT penetration was defined as the number of patients treated with CRT (CRT patients) divided by the prevalence of patients eligible for CRT. The number of CRT patients was estimated as the sum of CRT implantations in the last 5 years, the European Heart Rhythm Association (EHRA) White Book being used as the source. The prevalence of CRT indications was derived from the literature by applying three epidemiologic models, a synthesis of which indicates that 10% of heart failure (HF) patients are candidates for CRT. HF prevalence was considered to range from 1% to 2% of the general population, resulting in an estimated range of prevalence of CRT indication between 1000 and 2000 patients per million inhabitants. Similarly, the annual incidence of CRT indication, representing the potential target population once CRT has fully penetrated, was estimated as between 100 and 200 individuals per million. The results showed the best CRT penetration in Italy (47–93%), while in some countries it was less than 5% (Romania, Russian Federation, and Ukraine).

Conclusion

CRT penetration differs markedly among the countries analyzed. The main barriers are the lack of reimbursement for the procedure and insufficient awareness of guidelines by the referring physicians.

Biventricular / left ventricular pacing in hypertrophic obstructive cardiomyopathy: an overview

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant inherited genetic disease characterized by compensatory pathological left ventricle (LV) hypertrophy due to sarcomere dysfunction. In an important proportion of patients with HCM, the site and extent of cardiac hypertrophy results in severe obstruction to LV outflow tract (LVOT), contributing to disabling symptoms and increasing the risk of sudden cardiac death (SCD). In patients with progressive and/or refractory symptoms despite optimal pharmacological treatment, invasive therapies that diminish or abolish LVOT obstruction relieve heart failure-related symptoms, improve quality of life and could be associated with long-term survival similar to that observed in the general population. The gold standard in this respect is surgical septal myectomy, which might be supplementary associated with a reduction in SCD. Percutaneous techniques, particularly alcohol septal ablation (ASA) and more recently radiofrequency (RF) septal ablation, can achieve LVOT gradient reduction and symptomatic benefit in a large proportion of HOCM patients at the cost of a supposedly limited septal myocardial necrosis and a 10-20% risk of chronic atrioventricular block. After an initial period of enthusiasm, standard DDD pacing failed to show in randomized trials significant LVOT gradient reductions and objective improvement in exercise capacity. However, case reports and recent small pilot studies suggested that atrial synchronous LV or biventricular (biV) pacing significantly reduce LVOT obstruction and improve symptoms (acutely as well as long-term) in a large proportion of severely symptomatic HOCM patients not suitable to other gradient reduction therapies. Moreover, biV/LV pacing in HOCM seems to be associated with significant LV reverse remodelling.

Extrasystolic stimulation with bi-ventricular pacing: an acute haemodynamic evaluation

AIMS

Cardiac resynchronization therapy (CRT) by means of biventricular pacing (BiVP) is well established as a treatment for patients with heart failure (HF). Post-extrasystolic potentiation, (PESP) which involves a transient increase in myocardial contractility following a ventricular extrasystole, can be achieved using extrasystolic stimulation (ESS). On this basis, ESS has been proposed as a therapeutic. We assessed acute haemodynamic effects of ESS in the context of BiVP.

METHODS AND RESULTS

Patients (n = 15, left ventricular ejection fraction < 40%, QRS ≥ 125 ms) with HF, received BiVP in combination with right ventricular (RV) ESS (single stimulus or pulse train). Left ventricular (LV) and peripheral arterial pressures were recorded and dP/dt was monitored. Addition of RV ESS to BiVP pacing led to a 21% increase in maximum (max) dP/dt (P < 0.001) and an 8.5 mm Hg increase in a systolic arterial pressure (P < 0.001). The modest fall in end-diastolic pressure (3.3 mmHg, P < 0.001) observed during ESS and BiVP was prevented by maintaining baseline sinus rate. Varying ESS modes or pacing outputs was not associated with differences in haemodynamic parameters.

CONCLUSIONS

Biventricular pacing in combination with ESS, with maintenance of sinus rate, improves myocardial contractility in patients undergoing CRT.

Midterm 'super-response' to cardiac resynchronization therapy by biventricular pacing with fusion: insights from electro-anatomical mapping

Aims

Some authors recommend avoiding fusion with left ventricular (LV) intrinsic depolarization during cardiac resynchronization therapy (CRT). If fusion is still present during optimized biventricular (Biv) pacing and its long-term effects on the response to CRT are currently unknown. The aim of the study was to analyse the endocardial LV activation pattern induced by echocardiographically optimized Biv pacing and its influence on LV reverse remodelling.

Methods and results

Contact electro-anatomical mapping was performed in 15 heart failure (HF) patients with left bundle branch block and echocardiographically optimized CRT (seven ischaemic aetiology, 64 ± 8 years, three women, New York Heart Association class 3 ± 0.4, LV ejection fraction 25 ± 5%). Left ventricular activation maps were performed in sinus rhythm (SR), during DDD right ventricular apical (RVA) and optimized Biv pacing. Fusion with intrinsic rhythm during pacing was considered when LV septal activation was produced at least partially by intrinsic depolarization, when compared with LV activation map during SR. Patients were considered responders to CRT if they had ≥10% reduction in LV end-systolic volume (LVESV) after 6 months of CRT. During SR, the LV breakthrough was mid-septal (n = 12), basal septum (n = 2), and apical (n = 1). During RVA pacing, LV breakthrough shifted apical in all patients. Right ventricular apical/Biv pacing proved fusion with intrinsic depolarization in 8 of 15 patients. The PR interval was shorter in patients with fusion RVA/Biv pacing (164 ± 24 vs. 234 ± 55 ms, P = 0.006). There was a trend for shorter LV activation time (LV_at) in patients with fusion during RVA pacing (87 ± 33 vs. 113 ± 21 ms, P = 0.08) as well as during optimized Biv pacing (83 ± 18 vs. 104 ± 24 ms, P = 0.07), although LV_at was similar in SR (100 ± 22 vs. 106 ± 20, P = NS). In patients with fusion, 6 months responder rate was significantly higher (100 vs. 28.5%, P < 0.007) as was the degree of LVESV reduction (39 ± 17 vs. 1.0 ± 14%, P < 0.001).

Conclusion

Biventricular pacing with fusion may substantially increase the structural responder rate probably by shortening LV_at.

Bi-atrial and right atrial activation times help to differentiate focal from macroreentrant right atrial tachycardias

OBJECTIVE

The objective was to study atrial activation intervals and their relation to the tachycardia cycle length (TCL) as electrophysiologic parameters differentiating focal (FAT) from macroreentrant atrial tachycardias (MRAT) originating in the right atrium.

METHODS

In 21 patients (8 men) with 30 successfully ablated right atrial tachycardias (15 focal) the endocardial activity during tachycardia was registered using multipolar catheters in the right atrium and the coronary sinus. Using this catheter configuration we measured the tachycardia cycle length (TCL), biatrial activation (BAA), right atrial activation (RAA), left atrial activation (LAA), as well as the proportion of those intervals to TCL. In 14 patients, the measurements were repeated in sinus rhythm as well. The diagnostic accuracy of the ratio of BAA to TCL was assessed.

RESULTS

TCL was longer, but all other intervals and ratios were significantly shorter in FAT compared to MRAT (P < 0.05 for all parameters, except for LAA - P = NS). During sinus rhythm, patients with MRAT had prolonged RAA (P = 0.003), but not BAA and LAA (P = NS), compared to patients with FAT. A discriminating value of 40% for the ratio of BAA to TCL, compared to 50% and 30%, was found to have the best sensitivity, specificity, positive and negative predictive values for MRAT, as well as for FAT.

CONCLUSIONS

BAA, RAA, LAA and their relation to the TCL are significantly shorter in FATs compared to MRATs arising from the right atrium. The ratio of BAA to TCL obtained using a simple 2-catheter configuration, allows a rapid and reliable differentiation between FAT and MRAT.

Ice mapping during tachycardia in close proximity to the AV node is safe and offers advantages for transcatheter ablation procedures

BACKGROUND

Ablation during ongoing orthodromic reentry tachycardia (AVRT) and atrioventricular nodal reentry tachycardia (AVNRT) is not recommended using radiofrequency energy when the arrhythmia substrate is located in close proximity to the atrioventricular (AV) node due to a significant risk for inadvertent AV block. The aim of the study is to test the feasibility of ice mapping during tachycardias involving arrhythmia substrate located in close proximity to the AV node.

METHODS

This was a single-centre, prospective, randomized study. A total of 65 patients was screened and 30 patients with supraventricular arrhythmias were assigned either to a cryo or RF energy group after diagnosis of AVNRT (17 pts) or AVRT (13 pts) with an anteroseptal accessory pathway. RF ablation was performed using standard ablation techniques. In the cryo group, ice mapping was performed during tachycardia with cooling of the catheter tip temperature to a maximum of -40 degrees C. Ablation was performed only if ice mapping terminated the tachycardia without prolongation of the AV conduction.

RESULTS

The overall acute success rate was 84%, and was not different in the cryo and RF groups (85% vs. 82.4%, P = 0.43). Both fluoroscopy and the procedure times were comparable. There was a marked reduction in the mean number of applications in the cryo group [2 (1-6) vs. 7 (1-41), P = 0.002]. In one patient ablation was not attempted in the cryo group because of AV prolongation, and in two patients temporary second-degree AV block was observed in the RF group. After 12 months follow-up the long-term success rate was similar between the two groups.

CONCLUSIONS

(I) Ice mapping is a feasible method to determine the exact location of accessory pathways and of the slow pathway during tachycardia. (2) Ice mapping performed during tachycardia causes less ablation lesions without increasing the procedure and fluoroscopy times.

Mid-term echocardiographic follow up of left ventricular function with permanent right ventricular pacing in pediatric patients with and without structural heart disease

Background

Chronic right ventricular apical pacing may have detrimental effect on left ventricular function and may promote to heart failure in adult patients with left ventricular dysfunction.

Methods

A group of 99 pediatric patients with previously implanted pacemaker was studied retrospectively. Forty-three patients (21 males) had isolated congenital complete or advanced atrioventricular block. The remaining 56 patients (34 males) had pacing indication in the presence of structural heart disease. Thirty-two of them (21 males) had isolated structural heart disease and the remaining 24 (13 males) had complex congenital heart disease. Patients were followed up for an average of 53 ± 41.4 months with 12-lead electrocardiogram and transthoracic echocardiography. Left ventricular shortening fraction was used as a marker of ventricular function. QRS duration was assessed using leads V₅ or II on standard 12-lead electrocardiogram.

Results

Left ventricular shortening fraction did not change significantly after pacemaker implantation compared to preimplant values overall and in subgroups. In patients with complex congenital heart malformations shortening fraction decreased significantly during the follow up period. (0.45 ± 0.07 vs 0.35 ± 0.06, p = 0.015). The correlation between the change in left ventricular shortening fraction and the mean increase of paced QRS duration was not significant. Six patients developed dilated cardiomyopathy, which was diagnosed 2 months to 9 years after pacemaker implantation.

Conclusion

Chronic right ventricular pacing in pediatric patients with or without structural heart disease does not necessarily result in decline of left ventricular function. In patients with complex congenital heart malformations left ventricular shortening fraction shows significant decrease.

Evolution of left ventricular function in paediatric patients with permanent right ventricular pacing for isolated congenital heart block: a medium term follow-up

AIMS

We aimed to assess the evolution of left ventricular (LV) systolic function in children with right ventricular apical (RVA) pacing for isolated congenital heart block (ICHB) and to identify possible predictors of LV function deterioration. Right ventricular apical pacing can be detrimental to LV function in a significant number of adults. Effects in children are still controversial.

METHODS AND RESULTS

Left ventricular shortening fraction (LV SF) and QRS duration were retrospectively assessed in 45 children with RVA pacing for ICHB: before pacemaker (PM) implantation, immediately after and then regularly during a follow-up of 58.69 +/- 45.23 months. Patients were categorized as stable or deteriorators according to an arbitrarily chosen cut-off point of > or =7% decrease in LV SF. Lupus status was unknown. Overall LV SF did not change significantly (41.42% +/- 8.21 before pacing, 39.77% +/- 7.03 immediately after PM implant, 37.43% +/- 9.91 with chronic pacing, P = NS). Deteriorators (n = 13) had significantly higher baseline heart rate (57.5 +/- 8.7 vs. 46.9 +/- 10.5 bpm, P < 0.05) and baseline LV SF (46.17 +/- 8.13 vs. 38.4 +/- 6.4%; P < 0.05), a significantly higher proportion of them being implanted before 2 years of age: 8 of 13 (61.5%) vs. 5 of 25 (20%) in the stable group (P < 0.05). Deteriorators had a higher incidence of an initial epicardial lead and narrower native QRS.

CONCLUSION

Permanent RVA pacing for ICHB does not necessarily affect LV function in children. The risk of deterioration of LV function seems to be higher in children with higher baseline heart rate and better baseline LV SF, especially with pacing at a younger age, a narrower native QRS and RVA epicardial pacing site.

Right diaphragmatic paralysis following endocardial cryothermal ablation of inappropriate sinus tachycardia

Inappropriate sinus tachycardia (IST) is a rare disorder amenable to catheter ablation when refractory to medical therapy. Radiofrequency (RF) catheter modification/ablation of the sinus node (SN) is the usual approach, although it can be complicated by right phrenic nerve paralysis. We describe a patient with IST, who had symptomatic recurrences despite previous acutely successful RF SN modifications, including the use of electroanatomical mapping/navigation system. We decided to try transvenous cryothermal modification of the SN. We used 2 min applications at -85 degrees C at sites of the earliest atrial activation guided by activation mapping during isoprenaline infusion. Every application was preceded by high output stimulation to reveal phrenic nerve proximity. During the last application, heart rate slowly and persistently fell below 85 bpm despite isoprenaline infusion, but right diaphragmatic paralysis developed. At 6 months follow-up, the patient was asymptomatic and the diaphragmatic paralysis had partially resolved. This is the first report, we believe, of successful SN modification for IST by endocardial cryoablation, although this case also demonstrates the considerable risk of right phrenic nerve paralysis even with this ablation energy.

A simple algorithm for defining the mechanism and the chamber of origin in atrial tachycardias

INTRODUCTION

Although macroreentrant atrial tachycardia (MRAT) and focal atrial tachycardia (FAT) can be successfully cured by catheter ablation, the proper diagnosis and treatment of these arrhythmias can still be challenging.

AIM

The objective of this study is to develop an algorithm allowing rapid diagnosis of the mechanism and the chamber of origin of atrial tachycardia based on intracardiac catheter recordings from the right atrium and the coronary sinus (CS).

METHODS

A 2-stepped algorithm was designed: (1) The time of biatrial activation expressed as a percentage of the tachycardia cycle length served to discriminate FAT from MRAT. (2) In FAT, the direction of activation of the CS catheter and the earliest atrial activation were used to define the chamber of origin. In MRAT, the time of right atrium activation was determined or entrainment was used at different sites. Thirty-two intracardiac recordings were reviewed off-line after the algorithm by 4 electrophysiologists blinded to the mechanism and the chamber of origin. The results of their analysis were compared with the intraoperative diagnosis.

RESULTS

The algorithm correctly identified 11 (100%) of 11 FATs and 19 (90.4%) of 21 MRATs. The site of origin was correctly identified in 8 (72.7%) of 11 FATs and in 20 of 21 (95.2%) MRATs. The site of origin was misidentified in 3 FATs, all arising from the CS ostium.

CONCLUSIONS

This algorithm allows rapid discrimination between FAT and MRAT. The chamber of origin is detected with a high accuracy in MRAT. However, the earliest atrial activation taken as an isolated event is not a good predictor for the chamber of origin in FAT arising from the ostium of the CS.

Slow and wide QRS complex tachycardia as a unique complication following radiofrequency catheter ablation of a left-sided accessory pathway in a child

Radiofrequency lesions can, theoretically, be the substrate for new persistent arrhythmias. As far as we know, this has never previously been encountered after transcatheter ablation of accessory pathways. A child with Wolff-Parkinson-White syndrome was referred for radiofrequency catheter ablation of a left-sided accessory pathway. After successful ablation of the accessory pathway using a retrograde transaortic approach, the child developed an incessant wide QRS complex tachycardia at slow rate that was resistant to pharmacologic interventions. The focus of the tachycardia was identical to the ventricular site of insertion of the eliminated accessory pathway.

A comparative study of EEG suppressions induced by global cerebral ischemia and anoxia

Cerebral ischemia and anoxia induce sequential changes that include ionic redistribution, alteration of enzimatic reactions governing metabolism and intracellular signaling. Despite high technology instrumentation including positron emission, tomography and magnetic resonance imaging used to unravel the intricacies of cerebral blood flow and metabolism, the electroencephalography (EEG) retains a useful place in the evaluation of processes induced by cerebral ischemia, especially in experimental conditions. We have investigated in this study EEG suppression and recovery following global cerebral ischemia, obtained by "four vessel occlusion model", reperfusion and anoxia. Both cerebral ischemia and anoxia have produced a sudden diminution of electrical brain activity and flat line was recorded after 8-10 sec. in the ischemic rats, but after 35-40 sec. in the anoxic rats. After same period of time (2 min) of ischemia and anoxia EEG recovery has been faster in the ischemic rat.