True idiopathic ventricular fibrillation in out-of-hospital cardiac arrest survivors in the Swiss Canton Ticino: prevalence, clinical features, and long-term follow-up.

Aims: Out-of-hospital cardiac arrest (OHCA) in the absence of evident structural heart disease is rare and can be due to subclinical cardiomyopathy and primary electrical disorders, including idiopathic ventricular fibrillation (IVF) with early repolarization (ER) pattern. Aim of this study was to investigate prevalence, clinical features, and long-term prognosis of IVF in OHCA survivors with otherwise normal 12-lead electrocardiograms (ECGs). Methods and Results: Patients with IVF in the absence of ER pattern or atrioventricular conduction abnormalities were considered eligible for this study. A total of 3407 OHCAs occurred in our region from 2000 to 2014. Out-of-hospital cardiac arrests of presumed cardiac origin were 2192; of them, 644 presented with a ventricular arrhythmia (VT/VF) as first shockable rhythm. Among them, a total of 74 implantable cardioverter-defibrillators were implanted for secondary prevention. Ventricular arrhythmia was considered idiopathic in 11 (15%) of these patients. Over a mean follow-up time of 85 ± 47 months (median: 42 months), ECG was found abnormal in three cases. In the remaining eight patients (6 males; median age: 45 years), no ECG or structural abnormalities were detected during the follow-up. Prevalence of IVF in OHCA survivors with first-shockable rhythm was 1.2%. During the long-term follow-up, no patient died or experienced ICD interventions. No new echocardiographic abnormal findings were revealed. Conclusion: Idiopathic ventricular fibrillation is rare occurring in 1.2% of OHCA survivors presenting with a shockable rhythm. The initial diagnosis can change in up to 27% of cases. Patients with IVF and no ER pattern or AV conduction disturbances have a good prognosis during a long-term follow-up.

Occlusion of the infarct-related coronary artery presenting as acute coronary syndrome with and without ST-elevation: impact of inflammation and outcomes in a real-world prospective cohort.

BACKGROUND: Patients with ST-segment elevation typically feature total coronary occlusion (TCO) of the infarct-related artery (IRA) on angiography, which may result in worse outcomes. Yet, relying solely on electrocardiogram (ECG) findings may be misleading and those presenting with non-ST-segment elevation acute coronary syndromes (NSTE-ACSs) may have TCO as well. Herein, we aimed to delineate clinical characteristics and outcomes of patients with ACS stratified by IRA location. METHODS: A total of 4787 ACS patients were prospectively recruited between 2009 and 2017 in SPUM-ACS (ClinicalTrials.gov Identifier: NCT01000701). The primary endpoint was major adverse cardiovascular events (MACEs), a composite of all-cause death, non-fatal myocardial infarction and non-fatal stroke at 1 year. Multivariable-adjusted survival models were fitted using backward selection. RESULTS: A total of 4412 ACS patients were included in this analysis, 56.0% (n = 2469) ST-elevation myocardial infarction (STEMI) and 44.0% (n = 1943) NSTE-ACS. The IRA was the right coronary artery (RCA) in 33.9% (n = 1494), the left-anterior descending coronary artery (LAD) in 45.6% (n = 2013), and the left circumflex (LCx) in 20.5% (n = 905) patients. In STEMI patients, TCO (defined as TIMI 0 flow at angiography) was observed in 55% of cases with LAD, in 63% with RCA, and in 55% with LCx. In those presenting with NSTE-ACS, TCO was more frequent in those with LCx and RCA as compared to the LAD (27 and 24%, respectively, vs. 9%, P < 0.001). Among patients with NSTE-ACS, occlusion of the LCx was associated with an increased risk of MACE during 1 year after the index ACS (fully adjusted hazard ratio 1.68, 95% confidence interval 1.10-2.59, P = 0.02; reference: RCA and LAD). Features of patients with NSTE-ACS associated with TCO of the IRA included elevated lymphocyte and neutrophil counts, higher levels of high-sensitivity C reactive protein (hs-CRP) and high-sensitivity cardiac troponin T, lower eGFR, and notably a negative history of MI. CONCLUSION: In NSTE-ACS, both LCx and RCA involvement was associated with TCO at angiography despite the absence of ST-segment elevation. Involvement of the LCx, but not the LAD or RCA, as the IRA represented an independent predictor of MACE during 1-year follow-up. Hs-CRP, lymphocyte, and neutrophil counts were independent predictors of total IRA occlusion, suggesting a possible role of systemic inflammation in the detection of TCO irrespective of ECG presentation.

Temporal trends and long term follow-up of implantable cardioverter defibrillator therapy for secondary prevention: A 15-year single-centre experience.

BACKGROUND: The aim of this study was to determine overall and aetiology-related incidence of secondary prevention ICD implantation over the last 15years in Canton Ticino and to assess clinical outcome according to time period of implantation. METHODS AND RESULTS: Consecutive patients treated by implantation of an ICD for secondary prevention from 2000 to 2015 were included in the current study and compared between 5-year cohorts (2000/2004; 2005/2009; 2010/2015). Yearly implantation rate, changing in clinical presentation over years and events during follow-up were evaluated. One-hundred fifty six patients were included. ICD implantation rate increased from 2.1 in 2000-2005 to 5.1 in 2010-2015, respectively (p 0.001). There was an increase in the proportion of non-ischaemic patients and of ventricular tachycardia (VT) as presenting rhythm. No differences in appropriate ICD interventions were observed according to aetiology, presenting arrhythmia or type of device. Reverse remodelling was observed more often in non-ischaemic patients, without any influence on the occurrence of appropriate interventions. Previous myocardial infarction (MI), atrial fibrillation (AF), NYHA class 2-3 and left ventricular ejection fraction (LVEF)<35% were predictors of appropriate therapies during follow-up. CONCLUSIONS: Rate of implants for secondary prevention indication has almost doubled during the last 15years. Importantly, there has been a progressive increase of non-ischaemic patients receiving an ICD, and of VT as presenting rhythm. Patients had an overall good survival and a relatively low incidence of appropriate therapies. Improvement of ejection fraction did not correlate with risk reduction of ventricular arrhythmias.