Safety and efficacy of cryoablation for atrial fibrillation in young patients: A multicenter experience in the 1STOP project.

BACKGROUND: Atrial fibrillation (AF) is an uncommon arrhythmia in young adults without structural heart disease, and cryoballoon pulmonary vein isolation (CB-PVI) is an important therapeutic strategy for rhythm control in patients with drug-refractory AF. The aim of this analysis was to evaluate efficacy and safety of CB-PVI in a large cohort of young patients in comparison with middle-aged adults in a real-world setting. METHODS: From 2012 to 2020, a total of 3033 patients with AF underwent CB-PVI and were followed prospectively in the framework of the 1STOP Clinical Service project, involving 34 Italian centers. Out of 3033 total 1STOP project subjects, a subgroup of 1318 patients were defined which included a YOUNG group (age ≤ 45 years; n = 368) and a MIDDLE-AGED group (age 60-65 years; n = 950). RESULTS: The acute success rate of PVI did not differ between the two cohorts (99.9 ± 1.3% vs. 99.8 ± 3.2%, p = 0.415). There was no difference in procedural characteristics, and periprocedural complication rates were similar among the two cohort (1.9% vs. 2.3%, p = 0.646). The 12-month freedom from AF recurrence was 88.9% (95% confidence interval [CI]: 84.7-92.0) in the YOUNG cohort and 85.6% (95% CI: 82.9-88.0) in the MIDDLE-AGED group. At 36-month follow-up, freedom from AF recurrence was 72.4% (65.5%-78.2%) and 71.8% (67.7%-75.6%), respectively with no significant difference among groups (p = 0.550). CONCLUSION: CB-PVI had similar efficacy and safety in YOUNG and MIDDLE-AGED patients. Younger age did not affect acute procedural results, complication rate, or AF recurrence after a single procedure.

Multiparametric identification of subclinical atrial fibrillation after an embolic stroke of undetermined source.

BACKGROUND: Subclinical atrial fibrillation (SCAF) may represent a cause of embolic stroke of undetermined source (ESUS) and its detection has important implications for secondary prevention with anticoagulation. Indications to implantable cardiac monitors (ICM) include SCAF detection. The aims of this study were to (1) evaluate the frequency of ICM-detected SCAF; (2) determine predictors of SCAF; and (3) identify patients who would benefit most from ICM implantation. METHODS: Between February 2017 and November 2020, all consecutive patients referred for ICM implantation after a diagnosis of ESUS and without previous history of atrial fibrillation or atrial flutter were included in this study. SCAF was diagnosed if the ICM electrogram demonstrated an episode of irregularly irregular rhythm without distinct P waves lasting > 2 min. RESULTS: We enrolled 109 patients (age 66, SD = 13 years; 36% females). During a median follow-up of 19.2 (IQR 11.0-27.5) months, SCAF episodes were detected in 36 (33%) patients. Only abnormal P wave terminal force in lead V1, left atrial end-systolic indexed volume > 34 ml/m2, and BMI > 25 kg/m2 were independently associated with an increased risk of SCAF (HR 2.44, 95% CI 1.14-5.21, p = 0.021; HR 2.39, 95% CI 1.11-5.13, p = 0.026; and HR 2.64, 95% CI 1.06-6.49, p = 0.036 respectively). The ROC curve showed that the presence of all three parameters had the best accuracy (74%) to predict SCAF detection (sensitivity 39%, specificity 91%). CONCLUSION: A multiparametric evaluation has the best accuracy to predict SCAF in ESUS patients and may help identifying those who would benefit most from ICM.

Characteristics and hospital course of patients admitted for acute cardiovascular diseases during the coronavirus disease-19 outbreak.

INTRODUCTION: During the coronavirus disease-19 (COVID-19) outbreak in spring 2020, people may have been reluctant to seek medical care fearing infection. We aimed to assess the number, characteristics and in-hospital course of patients admitted for acute cardiovascular diseases during the COVID-19 outbreak. METHODS: We enrolled all consecutive patients admitted urgently for acute myocardial infarction, heart failure or arrhythmias from 1 March to 31 May 2020 (outbreak period) and 2019 (control period). We evaluated the time from symptoms onset to presentation, clinical conditions at admission, length of hospitalization, in-hospital medical procedures and outcome. The combined primary end point included in-hospital death for cardiovascular causes, urgent heart transplant or discharge with a ventricular assist device. RESULTS: A similar number of admissions were observed in 2020 (N = 210) compared with 2019 (N = 207). Baseline characteristics of patients were also similar. In 2020, a significantly higher number of patients presented more than 6 h after symptoms onset (57 versus 38%, P < 0.001) and with signs of heart failure (33 versus 20%, P = 0.018), required urgent surgery (13 versus 5%, P = 0.004) and ventilatory support (26 versus 13%, P < 0.001). Hospitalization duration was longer in 2020 (median 10 versus 8 days, P = 0.03). The primary end point was met by 19 (9.0%) patients in 2020 versus 10 (4.8%) in 2019 (P = 0.09). CONCLUSION: Despite the similar number and types of unplanned admissions for acute cardiac conditions during the 2020 COVID-19 outbreak compared with the same period in 2019, we observed a higher number of patients presenting late after symptoms onset as well as longer and more complicated clinical courses.

Screening of unknown atrial fibrillation through handheld device in the elderly.

OBJECTIVE: To estimate the prevalence of unknown atrial fibrillation (AF) in the elderly population of the Veneto Region, Italy. METHODS: 1820 patients aged ≥ 65 years with no history of AF and not anticoagulated were enrolled in primary-care settings. They underwent an opportunistic electrocardiogram screening with a handheld device (MyDiagnostick) designed to specifically detect AF. The electrocardiogram recordings were reviewed by the researchers, who confirmed the presence of AF. RESULTS: The device detected an arrhythmia in 143 patients, which was confirmed as AF in 101/143 (70.6%), with an overall prevalence of AF of 5.5% (101/1820). Prevalence of unknown AF resulted in 3.6% in patients aged 65-74 years, and 7.5% in patients age 75 or older, and increased according to CHA2DS2-VASc score: 3.5% in patients with a score of 1 or 2, 5.6% in patients with a score of 3, 7.0% in patients with a score of 4, and 7.2% in patients with a score ≥ 5. The detection rate was significantly higher in patients with mild symptoms compared to asymptomatic counterparts (24.1% vs. 4.0%, P < 0.0001). At multivariate analysis, congestive heart failure and age ≥ 75 years-old were independent predictors for screen-detected AF. CONCLUSIONS: An opportunistic screening with handheld device revealed an unexpectedly high prevalence of unknown AF in elderly patients with mild symptoms. Prevalence increased with age and CHA2DS2-VASc score.

Evaluation of mexiletine effect on conduction delay and bradyarrhythmic complications in patients with myotonic dystrophy type 1 over long-term follow-up.

BACKGROUND: Myotonic dystrophy type 1 (DM1) is a multisystemic disorder characterized by progressive cardiac conduction impairment, arrhythmias, and sudden death. Mexiletine is a sodium channel blocker drug used by patients with DM1 for treatment of myotonia, even though definitive proof of its safety over long-term follow-up is lacking. OBJECTIVE: The purpose of this study was to assess the impact of mexiletine for treatment of neurological symptoms on the composite endpoint of significant electrocardiogram modification (new onset or worsening of atrioventricular [AV] or intraventricular conduction delay) and bradyarrhythmic complications requiring pacemaker (PM) implantation (advanced AV block, symptomatic sinus pause >3 seconds). METHODS: This retrospective longitudinal study included a series of consecutive patients with genetically confirmed DM1 evaluated at our neurology and cardiology clinics from January 1, 2011, to January 1, 2020, who received mexiletine 200 mg twice daily. Patients with a PM, implantable cardioverter-defibrillator, or severe conduction abnormality (PQ interval ≥230 ms, complete bundle branch block, or atrial fibrillation) at enrollment were excluded. RESULTS: The study comprised 18 mexiletine-treated patients and 68 mexiletine-free controls. Over median follow-up of 53 months, the endpoint was reached by 4 (22%) mexiletine-treated patients and 23 (33%) non-mexiletine-treated patients (log-rank P = .45). In 3 non-mexiletine-treated patients, bradyarrhythmic complications requiring PM implantation were observed. At univariable analysis, only the presence of mild conduction delay (first-degree AV block with PQ interval <230 ms or left anterior fascicular block) at baseline predicted the endpoint (hazard ratio 2.22; 95% confidence interval 1.04-4.76). CONCLUSION: Mexiletine 200 mg twice daily is safe in patients with DM1 and no severe conduction abnormality.

The association between atrial fibrillation and Alzheimer's disease: fact or fallacy? A systematic review and meta-analysis.

BACKGROUND: The association between atrial fibrillation and dementia has been described. Whether a specific association exists between atrial fibrillation and Alzheimer's disease remains uncertain. This study aims to assess the association between atrial fibrillation and Alzheimer's disease through a systematic review and meta-analysis of the literature. METHODS: An exhaustive search of electronic databases up to October 2018 was conducted. Studies that identified patients with and without atrial fibrillation as well as patients with and without Alzheimer's disease and reported results of at least one relevant outcome, including hazard ratio of the association between atrial fibrillation and Alzheimer's disease were included in this analysis. The hazard ratios and their confidence interval were then pooled using a DerSimonian and Laird random effects model. RESULTS: Six studies enrolling a total of 56 370 patients were included. At baseline, the mean or median ages ranged from 50 to 78 years with a subsequent follow-up of 3 to 25 years. The random-effect pooled analysis showed a hazard ratio of 1.30 (95% confidence interval 1.01-1.59) and the heterogeneity was not significant, I 48.1%. All of the included studies were rated as good quality. CONCLUSION: Pooled analysis suggest that patients with atrial fibrillation may be exposed to an increased risk of developing new onset of Alzheimer's disease. Given the relevant clinical implications, further studies are required to corroborate these findings.