Air pollution and out-of-hospital cardiac arrest risk: a 7-year study from a highly polluted area.

AIMS: Globally, nearly 20% of cardiovascular disease deaths were attributable to air pollution. Out-of-hospital cardiac arrest (OHCA) represents a major public health problem; therefore, the identification of novel OHCA triggers is of crucial relevance. The aim of the study was to evaluate the association between air pollution (short-, mid-, and long-term exposures) and OHCA risk, during a 7-year period in a highly polluted urban area in northern Italy, with a high density of automated external defibrillators (AEDs). METHODS AND RESULTS: Out-of-hospital cardiac arrests were prospectively collected from the 'Progetto Vita Database' between 1 January 2010 and 31 December 2017; day-by-day air pollution levels were extracted from the Environmental Protection Agency stations. Electrocardiograms of OHCA interventions were collected from the AED data cards. Day-by-day particulate matter (PM) 2.5 and 10, ozone (O3), carbon monoxide (CO), and nitrogen dioxide (NO2) levels were measured. A total of 880 OHCAs occurred in 748 days. A significant increase in OHCA risk with a progressive increase in PM2.5, PM10, CO, and NO2 levels was found. After adjustment for temperature and seasons, a 9% and 12% increase in OHCA risk for each 10 µg/m3 increase in PM10 (P < 0.0001) and PM2.5 (P < 0.0001) levels was found. Air pollutant levels were associated with both asystole and shockable rhythm risk, while no correlation was found with pulseless electrical activity. CONCLUSION: Short- and mid-term exposures to PM2.5 and PM10 are independently associated with the risk of OHCA due to asystole or shockable rhythm.

Ventricular Fibrillation Recurrences in Successfully Shocked Out-of-Hospital Cardiac Arrests.

Background and Objectives: The prognostic impact of ventricular fibrillation (VF) recurrences after a successful shock in out-of-hospital cardiac arrest (OOHCA) is still poorly understood, and some evidence suggests a potential pro-arrhythmic effect of chest compressions in this setting. In the present analysis, we looked at the short-term and long-term prognosis of VF recurrences in OOHCA. And their potential association with chest compressions. Materials and Methods: The Progetto Vita, prospectively collecting data on all resuscitation efforts in the Piacenza province (Italy), was used for the present analysis. From the 461 OOHCAs found in a shockable rhythm, only those with optimal ECG tracings and good audio recordings (160) were assessed. Rhythms other than VF post-shock were analyzed five seconds after shock delivery and survival to hospital admission, hospital discharge, and long-term survival data over a 14-year follow-up were collected. Results: Population mean age was 64.4 ± 16.9 years, and 31.9% of all patients were female. Mean time to EMS arrival was 5.9 ± 4.5 min. Short- and long-term survival without neurological impairment were higher in patients without VF recurrence when compared to patients with VF recurrence, independently from the pre-induction rhythm (p < 0.001). After shock delivery, VF recurrence was higher when chest compressions were resumed early after discharge and more vigorously. Conclusions: VF recurrences after a shock could worsen short and long-term survival. The potential pro-arrhythmic effect of chest compressions should be factored in when considering the real risks and benefits of this procedure.

Outcomes after sudden cardiac arrest in sports centres with and without on-site external defibrillators.

OBJECTIVE: Sudden cardiac arrest (SCA) is a rare but tragic event during amateur sports activities. Our aim is to analyse whether availability of automated external defibrillators (AEDs) in amateur sports centres could impact on SCA survival. METHODS: This is an observational study. During an 18-year period, data regarding exercise-related SCA in sports centres were prospectively collected. Survival rates and time to response were compared between centres with an AED already available and centres where an AED was not already present. RESULTS: Out of 252 sports facilities, 207 (82%) acquired an AED during follow-up while 45 (18%) did not. From 1999 to 2014, there were 26 SCAs (24 (92%) men, 54±17 years old) with 15 (58%) of them in centres with on-site AED. Neurologically intact survival rates were 93% in centres with on-site AED and 9% in centres without (P<0.001). Presence of on-site AED, presence of shockable rhythm, first assistance by a lay bystander and time to defibrillation were all related to neurological intact survival, but the presence of on-site AED was the only independent predictor in the multivariate analysis. The use of on-site AED resulted in a lower time to first shock when compared with emergency medical system-delivered AED (3.3±1.4min vs 7.3±3.2 min; P=0.001). CONCLUSIONS: The presence of on-site AEDs is associated with neurologically intact survival after an exercise-related SCA. Continuous efforts are recommended in order to introduce AEDs in sports and fitness centres, implement educational programmes and increase common awareness about SCA.

Community-based automated external defibrillator only resuscitation for out-of-hospital cardiac arrest patients.

BACKGROUND: Speed is the cornerstone of rescue for out-of-hospital cardiac arrest. As a consequence, community participation programs have been initiated to decrease response times. Even in the very best of these programs, however, short-term survival rates hover around 10% and long-term survival rates are half that. In most locales, survival is far worse. In Piacenza, Italy, responders have been trained for more than a decade to use publicly available automated external defibrillators (AEDs) and eschew the performance of cardiopulmonary resuscitation (CPR). It is known locally as "Progetto Vita." METHODS: From 2001 to 2014, we prospectively collected outcome data on all Progetto Vita-treated patients and all 3271 standard emergency medical services (EMS) patients. Progetto Vita rescuers simply accessed a public AED, turned it on, and only followed its instructions. Progetto Vita rescuers did not do CPR of any sort. If EMS arrived prior to initiation or even completion of the Progetto Vita protocol, EMS-supplanted Progetto Vita efforts and patients were not included in the Progetto Vita cohort. Follow-up was collected by each responder's data files, medical record review, and use of the Italian system death index. All cardiac arrest patients' death status was validated in 100% of patients through August 1, 2014. FINDINGS: Survival to hospital discharge occurred in 39 (41.4%) of the 95 patients treated by Progetto Vita and in 193 (5.9%) of the 3271 EMS patients. At 13-year follow-up, the Kaplan-Meier estimates of survival were 31.8% when AEDs only were used and 2.4% for standard EMS/CPR response. Estimates of survival are significantly better for Progetto Vita AED-only therapy when survival was stratified by time to respond, gender, location of cardiac arrest, and shockable rhythm. Relative to the 95 EMS patients with the fastest response times, Progetto Vita intervention was associated with a more than 2-fold increased rate of survival. INTERPRETATION: This is the first demonstration of excellent long-term survival from out-of-hospital cardiac arrest by promoting speed and ease of lay AED response without CPR.

Transient QRS amplitude attenuation is associated with clinical recovery in patients with takotsubo cardiomyopathy.

BACKGROUND/OBJECTIVES: Low voltage QRS complexes (LQRSV) and amplitude attenuation of QRS voltage (AAQRS) have been described in takotsubo (TC) patients, and postulated as valuable pre-angiographic markers. The aim of this observational study is to evaluate potential diagnostic and prognostic features of QRS amplitude in TC and acute coronary syndrome (ACS) patients. METHODS: Fifty-eight patients with TC were matched with 58 patients with ACS according to age, gender, and presence or absence of ST elevation at hospital admission. A 12-lead ECG was recorded within 12h after symptoms onset, the day after coronary angiography (CA) and before hospital discharge. When available, ECGs prior and subsequent to the acute event were also collected. RESULTS: QRS amplitude showed a time related trend, with a first phase characterized by an initial decrease in amplitude in both groups and a second phase, with a progressive recovery of QRS amplitude in TC patients up to pre-event levels, while QRS amplitude in ACS patients remained substantially unchanged from admission onwards. Rise in AAQRS during hospitalization showed a positive linear association with systolic function recovery and both troponin I and CK-MB decrease (all p<0.01) in TC patients. A 20% increase of mean AAQRS from admission is able to predict LVEF recovery and troponin I and CK-MB normalization in TC patients with good sensitivity and specificity. CONCLUSIONS: LQRSV and AAQRS are not reliable in differentiating ACS from TC. However, QRS amplitude attenuation in TC is transient, and is linearly associated with systolic function recovery and cardiac biomarkers normalization.

Differences and similarities of repolarization patterns during hospitalization for Takotsubo cardiomyopathy and acute coronary syndrome.

Takotsubo cardiomyopathy (TC) is characterized by an acute transient left ventricular systolic dysfunction mimicking acute coronary syndrome (ACS) without significant coronary stenosis. The aim of this study was to examine the electrocardiographic repolarization patterns of TC and ACS and to compare them from hospital admission to hospital discharge. Forty-five patients with TC were matched with 45 patients with ACS according to age, gender, and presence or absence of ST elevation at hospital admission. A complete 12-lead electrocardiography was performed within 12 hours after symptoms onset and then repeated after 3, 5, and 7 days. All patients underwent coronary angiography, and patients with ACS also underwent percutaneous revascularization. Within 12 hours from the symptoms' onset, patients with TC had a significantly fewer number of leads with ST elevation and a significantly more number of leads with T-wave inversion. These differences, however, were not present after 72 hours and a similar trend was seen over time during the 7-day follow-up. Patients with TC had a significant longer corrected QT interval at admission and during the whole follow-up. In conclusion, in the electrocardiograms collected 12 hours within symptoms onset, patients with TC and those with ACS showed significant differences in cardiac repolarization. However, the number of leads with either ST-segment deviation or T-wave alterations in patients with TC soon matched the ACS group undergoing percutaneous revascularization. In contrast, corrected QT interval was persistently longer in patients with TC and, despite a similar reduction in length over time in both groups, it was still significantly longer after 7 days.