Atrioventricular nodal reentry tachycardia treatment using CARTO 3 V7 activation mapping: a new era of slow pathway radiofrequency ablation is under coming.

Background: Slow pathway (SP) ablation is the cornerstone for atrioventricular nodal reentry tachycardia (AVNRT) treatment, and a low-voltage bridge offers a good target during mapping using low x-ray exposure. We aimed to assess a new tool to identify SP by activation mapping using the last CARTO3® version, i.e., CARTO PRIME® V7 (Biosense Webster, Diamond Bar, CA, USA). Methods and results: Right atrial septum and triangle of Koch 3D-activation map were obtained from intracardiac contact mapping during low x-ray CARTO 3® procedure. In 60 patients (mean age 60.3 ± 14.7, 61% females) undergoing ablation for AVNRT, an automatic activation map using a DECANAV® mapping catheter and CARTO® Confidense™, Coherent, and FAM DX software modules were obtained. The SP was identified in all patients as the latest atrioventricular node activation area; RF catheter ablation (RFCA) in that region elicited junctional beats. The mean procedural time was 150.3 ± 48.3 min, the mean fluoroscopy time exposure was 2.9 ± 2 min, the mean dose-area product (DAP) was 16.5 ± 2.7 cGy/cm2. The mean number of RF applications was 3.9 ± 2, the mean ablation index was 428.6 ± 96.6, and the mean contact force was 8 ± 2.8 g. There were no adverse event during the procedure, and no AVNRT recurrences occurred during a mean follow-up of 14.3 ± 8.3 months. Conclusion: Ablation of the SP by automatic mapping using Confidense™, Coherent, and FAM DX software modules is an innovative, safe, and effective approach to AVNRT ablation. The CARTO3® V7 system shows on a 3D map the latest AV node activation area during sinus rhythm allowing low fluoroscopy time and highly effective RFCA.

The "Defibrillation Testing, Why Not?" survey. Testing of subcutaneous and transvenous defibrillators in the Italian clinical practice.

BACKGROUND: Defibrillation testing (DT) can be omitted in patients undergoing transvenous implantable cardioverter-defibrillator (T-ICD) implantation, but it is still recommended for patients at risk for a high defibrillation threshold and for ICD generator changes. Moreover, DT is still recommended on implantation of subcutaneous ICD (S-ICD). The aim of the present survey was to analyze the current practice of DT during T-ICD and S-ICD implantations. METHODS: In March 2021, an ad hoc questionnaire on the current performance of DT and the standard practice adopted during testing was completed at 72 Italian centers implanting S-ICD and T-ICD. RESULTS: 48 (67%) operators reported never performing DT during de-novo T-ICD implantations, while no operators perform it systematically. The remaining respondents perform it for patients at risk for a high defibrillation threshold. DT is never performed at T-ICD generator change. At the time of de-novo S-ICD implantation, DT is never performed by 9 (13%) operators and performed systematically by 48 (66%). The remaining operators frequently omit DT in patients with more severe systolic dysfunction. DT is not performed at S-ICD generator change by 92% of operators. DT is conducted by delivering a first shock energy of 65 J by 60% of operators, while the remaining 40% test lower energy values. CONCLUSIONS: In current clinical practice, most operators omit DT at T-ICD implantation, even when still recommended in the guidelines. DT is also frequently omitted at S-ICD implantation, and a wide variability exists among operators in the procedures followed during DT.

Long-Term Outcome After Out-of-Hospital Cardiac Arrest: An Utstein-Based Analysis.

Background: No data are available regarding long-term survival of out-of-hospital cardiac arrest (OHCA) patients based on different Utstein subgroups, which are expected to significantly differ in terms of survival. We aimed to provide the first long-term survival analysis of OHCA patients divided according to Utstein categories. Methods: We analyzed all the 4,924 OHCA cases prospectively enrolled in the Lombardia Cardiac Arrest Registry (Lombardia CARe) from 2015 to 2019. Pre-hospital data, survival, and cerebral performance category score (CPC) at 1, 6, and 12 months and then every year up to 5 years after the event were analyzed for each patient. Results: A decrease in survival was observed during the follow-up in all the Utstein categories. The risk of death of the "all-EMS treated" group exceeded the general population for all the years of follow-up with standardized mortality ratios (SMRs) of 23 (95%CI, 16.8-30.2), 6.8 (95%CI, 3.8-10.7), 3.8 (95%CI, 1.7-6.7), 4.05 (95%CI, 1.9-6.9), and 2.6 (95%CI, 1.03-4.8) from the first to the fifth year of follow-up. The risk of death was higher also for the Utstein categories "shockable bystander witnessed" and "shockable bystander CPR": SMRs of 19.4 (95%CI, 11.3-29.8) and 19.4 (95%CI, 10.8-30.6) for the first year and of 6.8 (95%CI, 6.6-13) and 8.1 (95%CI, 3.1-15.3) for the second one, respectively. Similar results were observed considering the patients discharged with a CPC of 1-2. Conclusions: The mortality of OHCA patients discharged alive from the hospital is higher than the Italian standard population, also considering those with the most favorable OHCA characteristics and those discharged with good neurological outcome. Long-term follow-up should be included in the next Utstein-style revision.

Antecedent Administration of Angiotensin-Converting Enzyme Inhibitors or Angiotensin II Receptor Antagonists and Survival After Hospitalization for COVID-19 Syndrome.

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) utilizes the angiotensin-converting enzyme-2 (ACE-2) receptor to enter human cells. Angiotensin-converting enzyme inhibitors (ACEI) and angiotensin II receptor antagonists (ARB) are associated with ACE-2 upregulation. We hypothesized that antecedent use of ACEI/ARB may be associated with mortality in coronavirus disease 2019 (COVID-19). Methods and Results We used the Coracle registry, which contains data of patients hospitalized with COVID-19 in 4 regions of Italy, and restricted analyses to those ≥50 years of age. The primary outcome was in-hospital mortality. Among these 781 patients, 133 (17.0%) used an ARB and 171 (21.9%) used an ACEI. While neither sex nor smoking status differed by user groups, patients on ACEI/ARB were older and more likely to have hypertension, diabetes mellitus, and congestive heart failure. The overall mortality rate was 15.1% (118/781) and increased with age (PTrend<0.0001). The crude odds ratios (ORs) for death for ACEI users and ARB users were 0.98, 95% CI, 0.60-1.60, P=0.9333, and 1.13, 95% CI, 0.67-1.91, P=0.6385, respectively. After adjusting for age, hypertension, diabetes mellitus, and congestive heart failure, antecedent ACEI administration was associated with reduced mortality (OR, 0.55; 95% CI, 0.31-0.98, P=0.0436); a similar, but weaker trend was observed for ARB administration (OR, 0.58; 95% CI, 0.32-1.07, P=0.0796). Conclusions In those aged ≥50 years hospitalized with COVID-19, antecedent use of ACEI was independently associated with reduced risk of inpatient death. Our findings suggest a protective role of renin-angiotensin-aldosterone system inhibition in patients with high cardiovascular risk affected by COVID-19.

Inpatient Mortality According to Level of Respiratory Support Received for Severe Acute Respiratory Syndrome Coronavirus 2 (Coronavirus Disease 2019) Infection: A Prospective Multicenter Study.

OBJECTIVES: To describe patients according to the maximum degree of respiratory support received and report their inpatient mortality due to coronavirus disease 2019. DESIGN: Analysis of patients in the Coracle registry from February 22, 2020, to April 1, 2020. SETTING: Hospitals in the Piedmont, Lombardy, Tuscany, and Lazio regions of Italy. PATIENTS: Nine-hundred forty-eight patients hospitalized for coronavirus disease 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 948 patients, 122 (12.87%) received invasive ventilation, 637 (67.19%) received supplemental oxygen only, and 189 (19.94%) received no respiratory support. The median (quartile 1-quartile 3) age was 65 years (54-76.59 yr), and there was evidence of differential respiratory treatment by decade of life (p = 0.0046); patients greater than 80 years old were generally not intubated. There were 606 men (63.9%) in this study, and they were more likely to receive respiratory support than women (p < 0.0001). The rate of in-hospital death for invasive ventilation recipients was 22.95%, 12.87% for supplemental oxygen recipients, and 7.41% for those who received neither (p = 0.0004). A sensitivity analysis of the 770 patients less than 80 years old revealed a lower, but similar mortality trend (18.02%, 8.10%, 5.23%; p = 0.0008) among the 14.42%, 65.71%, and 19.87% of patients treated with mechanical ventilation, supplemental oxygen only, or neither. Overall, invasive ventilation recipients who died were significantly older than those who survived (median age: 68.5 yr [60-81.36 yr] vs 62.5 yr [55.52-71 yr]; p = 0.0145). CONCLUSIONS: Among patients hospitalized for coronavirus disease 2019, 13% received mechanical ventilation, which was associated with a mortality rate of 23%.

Performance of the Durata implantable cardioverter defibrillator lead: results of an independent multicenter study.

AIMS: The high rate of implantable cardioverter defibrillator (ICD) lead failures related to the Sprint Fidelis' and Riata's design have raised serious concerns about the reliability of ICD leads. The St. Jude Medical Durata family of leads replaced the preceding Riata line following increased rates of lead failure (1.17% per year). The aim of our study was to evaluate the long-term performance of the Durata lead. METHODS: Eight hundred and eighteen Durata ICD leads were implanted in 11 Italian centers. The incidence of lead failure, defined as a sudden rise in long-term pacing or defibrillation impedance and/or a sudden change in R-wave amplitude and capture thresholds, was assessed. The incidences of lead dislodgment and lead perforation were also evaluated. RESULTS: During a median follow-up of 1353 days (3.7 years; 25-75th interquartile range 806-1887 days) lead failure occurred in 16/818 leads (0.54%/year). The overall survival, free of lead failure, was 98.9% at 3 years, 98.2% at 4 years and 97.5% at 5 years. Lead dislodgment occurred in 12/818 leads with an incidence of 0.4%/year. No cases of cardiac perforation were reported. No major adverse events were reported except for two cases of inappropriate shocks as a consequence of failure or dislodgment. CONCLUSION: Our study suggests that the Durata lead does not engender a higher risk of failure. Overall survival, free from lead failure, was found to be higher than previously reported for the Riata lead.

High rate of subcutaneous implantable cardioverter-defibrillator sensing screening failure in patients with Brugada syndrome: a comparison with other inherited primary arrhythmia syndromes.

Aims: Subcutaneous implantable cardioverter-defibrillator (S-ICD) can avoid important complications associated with transvenous leads in patients with inherited primary arrhythmia syndromes, who do not need pacing therapy. Few data are available on the percentage of patients with inherited arrhythmia syndromes eligible for S-ICD implantation. Aim of this study was to analyse the eligibility for S-ICD in a series of patients with Brugada syndrome (BrS), and to compare it with patients with other channelopathies. Methods and results: Patients presenting with BrS, long-QT syndrome (LQTS), early repolarization syndrome (ERS), and idiopathic ventricular fibrillation (IVF) were considered eligible for this study. ECG screening was performed by analysis of QRS complex and T wave morphology recorded in standing and supine position. Eligibility was defined when ≥1 sense vector was acceptable in both supine and standing position. A total of 100 patients (72 males; mean age: 46 ± 17 years) underwent S-ICD sensing screening. Sixty-one patients presented with BrS, 21 with LQTS, 14 with IVF, and 4 with ERS. Thirty-four patients with BrS (56%) presented with spontaneous type 1 ECG. In the other 27 patients (44%), type 1 ECG was unmasked by ajmaline. Overall, rate of screening failure was 13%. Patients with BrS had a higher rate of inappropriate morphology analysis as compared with other channelopathies (18% vs. 5%, P = 0.07) and had a lower number of suitable sensing vectors (49.6% vs. 84.7% vs. P < 0.001). Ajmaline challenge unmasked sensing failure in 14.8% of drug-induced BrS patients previously considered eligible. In all patients, the reason for sensing inappropriateness was due to the presence of high T wave voltages. Conclusion: S-ICD screening failure occurs in up to 13% of patients with inherited primary arrhythmia syndromes. Patients with BrS present a higher rate of screening failure as compared with other cardiac channelopathies.

Submammary device implantation. Good long-term performance and better patients' satisfaction. A single-center experience.

INTRODUCTION: Device related distress negatively affects the quality of life of cardiac device recipients mostly of women. A submammary approach has been proposed to reduce the physical impact of the implantation. Our aim was to assess the safety of this approach and to evaluate the patients' acceptance of the device. METHODS: We enrolled 42 patients who underwent a submammary device. The primary endpoint was the need for implant revision that was assessed in the study group compared with the overall control group of 72 standard cardiac device recipients (29 females and 43 males)and with the female group (29 females of controls). In the female population (42 women of the submammary group and 29 of controls) patients' acceptance was calculated with the Florida Patient Acceptance Survey (FPAS). RESULTS: The rate of implant revision was similar in the two groups and the revision-free survival was comparable with a median follow-up of about six years (Log rank test p=0.949). Similar results were found when considering only the female population. Patients' acceptance was greater in the submammary group [total FPAS 85 (95%CI 83-86) vs 74.5 (95%CI 70.2-77.3) p<0,001] and a strongly significant superiority of the submammary group was found regarding body image concerns [10 (95%CI 10-10) vs 8 (95%CI 8-8) p<0.001) and device related distress [23 (95%CI 22-23) vs 1 (95%CI 1-1) p<0.001]. CONCLUSIONS: Submammary device implantation is safe and more accepted than standard approach. Our results should encourage cardiologists to suggest this approach to their patients for a better acceptance of the therapy.

Tumor necrosis factor-α predicts response to cardiac resynchronization therapy in patients with chronic heart failure.

BACKGROUND: Pro-inflammatory cytokines contribute to the pathophysiology of heart failure (HF) and are up-regulated in affected patients. We investigated whether pro-inflammatory cytokines might predict the response to cardiac resynchronization therapy (CRT). METHODS AND RESULTS: Plasma levels of tumor necrosis factor-α (TNF-α) and interleukin-6 were assessed in 91 patients before CRT. Response to CRT was defined as a decrease ≥15% in left ventricular end-systolic volume (LVESV) at 6 months. Baseline TNF-α did correlate with LVESV reduction (P=0.001) after CRT. The subject group was divided according to tertiles of TNF-α. From the lower to the upper tertile LVESV (-31±28%, -17±17%, -9±22%) and LV end-diastolic volume (-23±25%, -14±16%, -4±18%) were progressively less reduced after CRT (P<0.001). The proportion of responders to CRT was 70%, 42% and 33%, according to the lower, intermediate and upper tertile of TNF-α distribution (P=0.01). Serious cardiac events (cardiac death, HF hospitalization or urgent heart transplantation) occurred in 63% of patients in the upper tertile vs. 32% and 17% in the intermediate and lower tertiles, respectively, during a median follow-up of 47 months (P<0.001). CONCLUSIONS: Circulating TNF-α predicts the degree of LV reverse remodeling after CRT and may contribute to the early identification of those patients at higher risk of events after device implantation.

A comprehensive electrocardiographic, molecular, and echocardiographic study of Brugada syndrome: validation of the 2013 diagnostic criteria.

BACKGROUND: The debate on the diagnostic value of high intercostal spaces (ICSs) and of the number of diagnostic leads in Brugada syndrome (BrS) has been settled by a recent expert consensus statement. OBJECTIVE: To test the validity, and the underlying anatomy, of the new electrocardiographic (ECG) diagnostic criteria using echocardiographic, molecular, and clinical evidence in 1 clinical study population with BrS. METHODS: We analyzed 114 patients with BrS and with a spontaneous or drug-induced type 1 ECG pattern recorded in 1 or more right precordial leads in fourth, third, and second ICSs. The right ventricular outflow tract (RVOT) was localized by using echocardiography. All probands were screened on the SCN5A gene. RESULTS: The percentage of mutation carriers (MCs) and the event rate were similar regardless of the diagnostic ICS (fourth vs high ICSs: MCs 23% vs 19%; event rate 22% vs 28%) and the number of diagnostic leads (1 vs ≥2: MCs 20% vs 22%; event rate 22% vs 27%). The concordance between RVOT anatomical location and the diagnostic ICSs was 86%. The percentage of the diagnostic ECG pattern recorded was significantly increased by the exploration of the ICSs showing RVOT by echocardiography (echocardiography-guided approach vs conventional approach 100% vs 43%; P < .001). CONCLUSION: The high ICSs are not inferior to the standard fourth ICS for the ECG diagnosis of BrS, and the interindividual variability depends on the anatomical location of the RVOT as assessed by using echocardiography. This approach significantly increases diagnostic sensitivity without decreasing specificity and fully supports the recently published new diagnostic criteria.

Vagal reflexes following an exercise stress test: a simple clinical tool for gene-specific risk stratification in the long QT syndrome.

OBJECTIVES: The study assessed whether heart rate (HR) reduction following an exercise stress test (ExStrT), an easily quantifiable marker of vagal reflexes, might identify high- and low-risk long QT syndrome (LQTS) type 1 (LQT1) patients. BACKGROUND: Identification of LQTS patients more likely to be symptomatic remains elusive. We have previously shown that depressed baroreflex sensitivity, an established marker of reduced vagal reflexes, predicts low probability of symptoms among LQT1. METHODS: We studied 169 LQTS genotype-positive patients < 50 years of age who performed an ExStrT with the same protocol, on and off ß-blockers including 47 South African LQT1 patients all harboring the KCNQ1-A341V mutation and 122 Italian LQTS patients with impaired (I(Ks)-, 66 LQT1) or normal (I(Ks)+, 50 LQT2 and 6 LQT3) I(Ks) current. RESULTS: Despite similar maximal HR and workload, by the first minute after cessation of exercise the symptomatic patients in both I(Ks)- groups had a greater HR reduction compared with the asymptomatic (19 ± 7 beats/min vs. 13 ± 5 beats/min and 27 ± 10 beats/min vs. 20 ± 8 beats/min, both p = 0.009). By contrast, there was no difference between the I(Ks)+ symptomatic and asymptomatic patients (23 ± 9 beats/min vs. 26 ± 9 beats/min, p = 0.47). LQT1 patients in the upper tertile for HR reduction had a higher risk of being symptomatic (odds ratio: 3.28, 95% confidence interval: 1.3 to 8.3, p = 0.012). CONCLUSIONS: HR reduction following exercise identifies LQT1 patients at high or low arrhythmic risk, independently of ß-blocker therapy, and contributes to risk stratification. Intense exercise training, which potentiates vagal reflexes, should probably be avoided by LQT1 patients.

Congenital short QT syndrome.

The Short QT Syndrome is a recently described new genetic disorder, characterized by abnormally short QT interval, paroxysmal atrial fibrillation and life threatening ventricular arrhythmias. This autosomal dominant syndrome can afflict infants, children, or young adults; often a remarkable family background of cardiac sudden death is elucidated. At electrophysiological study, short atrial and ventricular refractory periods are found, with atrial fibrillation and polymorphic ventricular tachycardia easily induced by programmed electrical stimulation. Gain of function mutations in three genes encoding K(+) channels have been identified, explaining the abbreviated repolarization seen in this condition: KCNH2 for I(kr) (SQT1), KCNQ1 for I(ks) (SQT2) and KCNJ2 for I(k1) (SQT3). The currently suggested therapeutic strategy is an ICD implantation, although many concerns exist for asymptomatic patients, especially in pediatric age. Pharmacological treatment is still under evaluation; quinidine has shown to prolong QT and reduce the inducibility of ventricular arrhythmias, but awaits additional confirmatory clinical data.