Role of genetic testing in young patients with idiopathic atrioventricular conduction disease.

AIMS: To investigate the role of genetic testing in patients with idiopathic atrioventricular conduction disease requiring pacemaker (PM) implantation before the age of 50 years. METHODS AND RESULTS: All consecutive PM implantations in Southern Switzerland between 2010 and 2019 were evaluated. Inclusion criteria were: (i) age at the time of PM implantation: < 50 years; (ii) atrioventricular block (AVB) of unknown aetiology. Study population was investigated by ajmaline challenge and echocardiographic assessment over time. Genetic testing was performed using next-generation sequencing panel, containing 174 genes associated to inherited cardiac diseases, and Sanger sequencing confirmation of suspected variants with clinical implication. Of 2510 patients who underwent PM implantation, 15 (0.6%) were young adults (median age: 44 years, male predominance) presenting with advanced AVB of unknown origin. The average incidence of idiopathic AVB computed over the 2010-2019 time window was 0.7 per 100 000 persons per year (95% CI 0.4-1.2). Most of patients (67%) presented with specific genetic findings (pathogenic variant) or variants of uncertain significance (VUS). A pathogenic variant of PKP2 gene was found in one patient (6.7%) with no overt structural cardiac abnormalities. A VUS of TRPM4, MYBPC3, SCN5A, KCNE1, LMNA, GJA5 genes was found in other nine cases (60%). Of these, three unrelated patients (20%) presented the same heterozygous missense variant c.2531G > A p.(Gly844Asp) in TRPM4 gene. Diagnostic re-assessment over time led to a diagnosis of Brugada syndrome and long-QT syndrome in two patients (13%). No cardiac events occurred during a median follow-up of 72 months. CONCLUSION: Idiopathic AVB in adults younger than 50 years is a very rare condition with an incidence of 0.7 per 100 000 persons/year. Systematic investigations, including genetic testing and ajmaline challenge, can lead to the achievement of a specific diagnosis in up to 20% of patients. Heterozygous missense variant c.2531G > A p.(Gly844Asp) in TRPM4 gene was found in an additional 20% of unrelated patients, suggesting possible association of the variant with the disease.

Paediatric and adolescent athletes in Switzerland: age-adapted proposals for pre-participation cardiovascular evaluation.

High-level sports competition is popular among Swiss youth. Even though preparticipation evaluation for competitive athletes is widespread, screening strategies for diseases responsible for sudden death during sport are highly variable. Hence, we sought to develop age-specific preparticipation cardiovascular evaluation (PPCE) proposals for Swiss paediatric and adolescent athletes (under 18 years of age). We recommend that all athletes practising in a squad with a training load of at least 6 hours per week should undergo PPCE based on medical history and physical examination from the age of 12 years on. Prior to 12 years, individual judgement of athletic performance is required. We suggest the inclusion of a standard 12-lead electrocardiogram (ECG) evaluation for all post-pubertal athletes (or older than 15 years) with analysis in accordance with the International Criteria for ECG Interpretation in Athletes. Echocardiography should not be a first-line screening tool but rather serve for the investigation of abnormalities detected by the above strategies. We recommend regular follow-up examinations, even for those having normal history, physical examination and ECG findings. Athletes with an abnormal history (including family history), physical examination and/or ECG should be further investigated and pathological findings discussed with a paediatric cardiologist. Importantly, the recommendations provided in this document are not intended for use among patients with congenital heart disease who require individualised care according to current guidelines.

Management of hemodynamically stable wide QRS complex tachycardia in patients with implantable cardioverter defibrillators.

Management of hemodynamically stable, incessant wide QRS complex tachycardia (WCT) in patients who already have an implantable cardioverter defibrillator (ICD) is challenging. First-line treatment is performed by medical staff who have no knowledge on programmed ICD therapy settings and there is always some concern for unexpected ICD shock. In these patients, a structured approach is necessary from presentation to therapy. The present review provides a systematic approach in four distinct phases to guide any physician involved in the management of these patients: PHASE I: assessment of hemodynamic status and use of the magnet to temporarily suspend ICD therapies, especially shocks; identification of possible arrhythmia triggers; risk stratification in case of electrical storm (ES). PHASE II: The preparation phase includes reversal of potential arrhythmia "triggers", mild patient sedation, and patient monitoring for therapy delivery. Based on resource availability and competences, the most adequate therapeutic approach is chosen. This choice depends on whether a device specialist is readily available or not. In the case of ES in a "high-risk" patient an accelerated patient management protocol is advocated, which considers urgent ventricular tachycardia transcatheter ablation with or without mechanical cardiocirculatory support. PHASE III: Therapeutic phase is based on the use of intravenous anti-arrhythmic drugs mostly indicated in this clinical context are presented. Device interrogation is very important in this phase when sustained monomorphic VT diagnosis is confirmed, then ICD ATP algorithms, based on underlying VT cycle length, are proposed. In high-risk patients with intractable ES, intensive patient management considers MCS and transcatheter ablation. PHASE IV: The patient is hospitalized for further diagnostics and management aimed at preventing arrhythmia recurrences.

Swiss National Registry on Catheter Ablation Procedures: Changing Trends over the Last 20 Years.

The Swiss Ablation Registry provides a national database for electrophysiologic studies and catheter ablations. We analyzed the database to provide an in-depth look at changing trends over the last 20 years. During the study period a total of 78622 catheter ablations (age 61.0 ± 1.2 years; 63.7% male) were performed in 29 centers. The number of ablations increased by approximately ten-fold in 20 years. Ablation for atrial fibrillation (AF) was the main driver behind this increase, with more than hundred-fold (39.7% of all ablations in 2019). Atrioventricular-nodal-reentrant-tachycardia (AVNRT) and accessory pathways, being the main indications for ablation in 2000 (44.1%/25.1%, respectively), made up of only a small proportion (15.2%/3.5%,) respectively in 2019. Fluoroscopy, ablation, and procedure durations were reduced for all ablations over time. The highest repeat ablations were performed for ventricular tachycardia and AF (24.4%/24.3%). The majority of ablations (63.0%) are currently performed in private hospitals and non-university public hospitals whereas university hospitals had dominated (82.4%) at the turn of the century. A pronounced increase in the number of catheter ablations in Switzerland was accompanied by a marked decrease in fluoroscopy, ablation, and procedure durations. We observed a shift toward more complex procedures in older patients with comorbidities.

Pediatric athletes' ECG and diagnostic performance of contemporary ECG interpretation criteria.

BACKGROUND: Electrocardiographic (ECG) pre-participation screening(PPS) can prevent sudden cardiac death(SCD) but the Interpretation of the athlete's ECG is based on specific criteria addressed for adult athletes while few data exist about the pediatric athlete's ECG. We aimed to assess the features of pediatric athletes' ECG and compared the diagnostic performance of 2017 International ECG recommendation, 2010 European Society of Cardiology recommendation and 2013-Seattle criteria in detecting clinical conditions at risk of SCD. METHODS: 886 consecutive pediatric athletes (mean age 11.7 ± 2.5 years; 7-16-years) were enrolled and prospectively evaluated with medical history, physical examination, resting and exercise ECG and transthoracic echocardiography during their PPS. RESULTS: The most common physiological ECG patterns in pediatric athletes were isolated left ventricular hypertrophy criteria (26.9%), juvenile T-wave pattern (22%) and early repolarization pattern (13.2%). The most frequent borderline abnormalities were left axis deviation (1.8%) and right axis deviation (0.9%) while T-wave inversion (0.8%) especially located in inferior leads (0.7%) was the most prevalent abnormal findings. Seven athletes (0.79%) were diagnosed with a condition related to SCD. Compared to Seattle and ESC, the International improved ECG specificity (International = 98% ESC = 64% Seattle = 95%) with lower sensitivity (ESC and Seattle 86%vs International 57%). The false-positive rate decreases from 36% of ESC to 2.2% of International but the latter showed a higher false-negative rate(0.34%). CONCLUSION: Pediatric athletes like the adult counterpart exhibit a high prevalence of ECG abnormalities mostly representing training-related ECG adaptation. The International criteria showed a lower false-positive rate but at the cost of loss of sensitivity.

Impact of early sports specialisation on paediatric ECG.

Athletes of pediatric age are growing in number. They are subject to a number of risks, among them sudden cardiac death (SCD). This study aimed to characterize the pediatric athlete population in Switzerland, to evaluate electrocardiographic findings based on the International Criteria for electrocardiography (ECG) Interpretation in Athletes, and to analyze the association between demographic data, sport type, and ECG changes. Retrospective, observational study of pediatric athletes (less than 18 years old) including medical history, physical examination, and a 12-lead resting ECG. The primary focus was on identification of normal, borderline, and abnormal ECG findings. The secondary observation was the relation between ECG and demographic, anthropometric, sport-related, and clinical data. The 891 athletes (mean 14.8 years, 35% girls) practiced 45 different sports on three different levels, representing all types of static and dynamic composition of the Classification of Sports by Mitchell. There were 75.4% of normal ECG findings, among them most commonly early repolarization, sinus bradycardia, and left ventricular hypertrophy; 4.3% had a borderline finding; 2.1% were abnormal and required further investigations, without SCD-related diagnosis. While the normal ECG findings were related to sex, age, and endurance sports, no such observation was found for borderline or abnormal criteria. Our results in an entirely pediatric population of athletes demonstrate that sex, age, and type of sports correlate with normal ECG findings. Abnormal ECG findings in pediatric athletes are rare. The International Criteria for ECG Interpretation in Athletes are appropriate for this age group.

Prevalence of abnormal electrocardiograms in Swiss elite athletes detected with modern screening criteria.

AIMS OF THE STUDY: Sudden cardiac arrest in athletes is a rare but dramatic event. The value of a routine electrocardiogram (ECG) during preparticipation screening (PPS) remains controversial, partly because of the relatively high number of false positive findings. Our study aimed to evaluate the prevalence of abnormal ECGs in consecutive Swiss elite athletes, overall and with regard to different sports classes, using modern screening criteria. METHODS: We analysed the 12-lead resting ECGs of high-level elite athletes (age ≥14 years) recorded at the Swiss Olympic Medical Centre Magglingen between 2013 and 2016 during routine PPS. The overall prevalence of abnormal ECGs was evaluated and compared in accordance with the original and revised Seattle criteria. Sports disciplines were categorised according to their static (estimated percentage of maximal voluntary contraction, I-III) and dynamic (estimated percentage of maximal oxygen uptake, A-C) components, and the prevalence of abnormal ECGs compared between sports classes by Fisher's exact test (with alpha set at 0.05). RESULTS: ECGs from 287 consecutive athletes were analysed (64.1% male; 99.7% Caucasian; median age 20.4 ± 4.9 years; median weekly training volume 17.7 ± 7.1 hours). Based on original Seattle criteria, eight (2.8%) ECGs were classified as abnormal: three T-wave inversion (TWI), one Q-wave duration >40 ms, two QRS left axis deviation, two Q-wave amplitude >3 mm. The use of the revised Seattle criteria reduced the number of abnormal ECGs to four (1.4%): three TWI, one Q-wave duration >40 ms. Further cardiological work-up revealed an underlying structural heart disease in only one of these four athletes (inferolateral TWI on ECG), consisting of very localised mid-wall fibrosis suggestive of former myocarditis. There was a significant difference in occurrence of abnormal ECGs between the different sports categories (p = 0.018). All four abnormal ECGs according to the revised Seattle criteria occurred in the high dynamic sport classes (IIC and IIIC); three out of the four were found in the high dynamic high static class (IIIC). CONCLUSIONS: In our cohort of high-level elite athletes, the prevalence of abnormal ECGs according to modern screening criteria was very low. All athletes with an abnormal ECG performed high dynamic sports. Less than one percent of our athletes had a new relevant cardiac diagnosis.

Cardiovascular evaluation of middle-aged individuals engaged in high-intensity sport activities: implications for workload, yield and economic costs.

BACKGROUND: The European Association of Cardiovascular Prevention and Rehabilitation (EACPR) recommends cardiovascular evaluation of middle-aged individuals engaged in sport activities. However, very few data exist concerning the impact of such position stand. We assessed the implications on workload, yield and economic costs of this preventive strategy. METHODS: Individuals aged 35-65 years engaged in high-intensity sports were examined following the EACPR protocol. Athletes with abnormal findings or considered at high-cardiovascular risk underwent additional examinations. The costs of the overall evaluation until diagnosis were calculated according to Swiss medical rates. RESULTS: 785 athletes (73% males, 46.8±7.3 years) were enrolled over a 13-month period. Among them, 14.3% required additional examinations: 5.1% because of abnormal ECG, 4.7% due to physical examination, 4.1% because of high-cardiovascular risk and 1.6% due to medical history. A new cardiovascular abnormality was established in 2.8% of athletes, severe hypercholesterolaemia in 1% and type 2 diabetes in 0.1%. Three (0.4%) athletes were considered ineligible for high-intensity sports, all of them discovered through an abnormal ECG. No athlete was diagnosed with significant coronary artery disease on the basis of a high-risk profile or an exercise ECG. The cost was US$199 per athlete and US$5052 per new finding. CONCLUSIONS: Cardiovascular evaluation of middle-aged athletes detected a new cardiovascular abnormality in about 3% of participants and a high-cardiovascular risk profile in about 4%. Some of these warranted exclusion of the athlete from high-intensity sport. The overall evaluation seems to be feasible at reasonable costs.

Costs and yield of a 15-month preparticipation cardiovascular examination with ECG in 1070 young athletes in Switzerland: implications for routine ECG screening.

BACKGROUND: The usefulness and modalities of cardiovascular screening in young athletes remain controversial, particularly concerning the role of 12-lead ECG. One of the reasons refers to the presumed false-positive ECGs requiring additional examinations and higher costs. Our study aimed to assess the total costs and yield of a preparticipation cardiovascular examination with ECG in young athletes in Switzerland. METHODS: Athletes aged 14-35 years were examined according to the 2005 European Society of Cardiology (ESC) protocol. ECGs were interpreted based on the 2010 ESC-adapted recommendations. The costs of the overall screening programme until diagnosis were calculated according to Swiss medical rates. RESULTS: A total of 1070 athletes were examined (75% men, 19.7±6.3 years) over a 15-month period. Among them, 67 (6.3%) required further examinations: 14 (1.3%) due to medical history, 15 (1.4%) due to physical examination and 42 (3.9%) because of abnormal ECG findings. A previously unknown cardiac abnormality was established in 11 athletes (1.0%). In four athletes (0.4%), the abnormality may potentially lead to sudden cardiac death and all of them were identified by ECG alone. The cost was 157,464 Swiss francs (CHF) for the overall programme, CHF147 per athlete and CHF14,315  per finding. CONCLUSIONS: Cardiovascular preparticipation examination in young athletes using modern and athlete-specific criteria for interpreting ECG is feasible in Switzerland at reasonable cost. ECG alone is used to detect all potentially lethal cardiac diseases. The results of our study support the inclusion of ECG in routine preparticipation screening.

Rapid-growing left intraventricular cardiac hemangioma.

A 62 years old man with Child B liver cirrhosis, prostate cancer and a recent colon carcinoma resection was referred to our cardiology department for trans-thoracic-echocardiography (TTE) in order to establish left ventricular function before starting chemotherapy. TTE revealed a mobile mass (16 x 8 mm) attached to the anterior-medial left ventricular wall, protruding and swinging within the left ventricle cavity. At follow-up TTE showed growing of the intra-cardiac tumor up to 27 x 10 mm, corresponding to a size increase of 1 mm/month. Among different pathologies a rapid growing benign tumor with a high risk of systemic embolisation or an endocardial blood cyst were retained as possible diagnoses. Given the progression of the cardiac finding and the patient's improved general condition, surgical resection of the cardiac mass was performed. Histological examination revealed a mixed capillary/cavernous hemangioma. This case shows the unusual concomitant appearance of a rapid growing cavernous hemangioma which rarely located at ventricular level and the feasibility of cardiac resection without further sequelae in a poly-morbid patient.