Short-term exposure to environmental parameters and onset of ST elevation myocardial infarction. The CARDIO-ARSIF registry

Explore the effect of apparent temperature and air pollutants on the admission rate of acute myocardial infarction in Chongqing, China: a time-series study

OBJECTIVE

Limited research has been conducted on the correlation between apparent temperature and acute myocardial infarction (AMI), as well as the potential impact of air pollutants in modifying this relationship. The objective of this study is to investigate the lagged effect of apparent temperature on AMI and assess the effect modification of environmental pollutants on this association.

DESIGN

A time-series study.

SETTING AND PARTICIPANTS

The data for this study were obtained from the Academy of Medical Data Science at Chongqing Medical University, covering daily hospitalisations for AMI between 1 January 2015 and 31 December 2016. Meteorological and air pollutant data were provided by China's National Meteorological Information Centre.

OUTCOME MEASURES

We used a combined approach of quasi-Poisson generalised linear model and distributed lag non-linear model to thoroughly analyse the relationships. Additionally, we employed a generalised additive model to investigate the interaction between air pollutants and apparent temperature on the effect of AMI.

RESULT

A total of 872 patients admitted to hospital with AMI were studied based on the median apparent temperature (20.43°C) in Chongqing. Low apparent temperature (10th, 7.19℃) has obvious lagged effect on acute myocardial infarction, first appearing on the 8th day (risk ratio (RR) 1.081, 95% CI 1.010 to 1.158) and the greatest risk on the 11th day (RR 1.094, 95% CI 1.037 to 1.153). No lagged effect was observed at high apparent temperature. In subgroup analysis, women and individuals aged 75 and above were at high risk. The interaction analysis indicates that there exist significant interactions between PM2.5 and high apparent temperature, as well as nitrogen dioxide (NO2) and low apparent temperature.

CONCLUSION

The occurrence of decreased apparent temperature levels was discovered to be linked with a heightened relative risk of hospitalisations for AMI. PM2.5 and NO2 have an effect modification on the association between apparent temperature and admission rate of AMI.

[Registry CARDIO-ARSIF - Database on coronary angiography and percutaneous coronary invasive performed in Île-de-France]

The CARDIO-ARSIF registry has been continuously collecting comprehensive data on coronary angiography and percutaneous coronary interventions (PCI) performed in the 36 catheterization laboratories across the Île-de-France region since 2000. Over the period from 2003 to 2022, this registry has recorded information from more than 330,000 patients, encompassing more than one million procedures. Among these procedures, 58% consisted of coronary angiography, 13% were percutaneous coronary interventions (PCI), and the remaining 28% were PCI performed on an ad-hoc basis. This extensive dataset serves as a valuable resource for both qualitative and quantitative assessments of practices and the relevance of procedures in the field of coronary invasive cardiology. The results of these analyses undergo annual validation by a dedicated scientific committee and are shared with the teams of investigators. The exploitation of this data has led to scientific publications, with one notable finding being a consistent reduction in the radiation doses received by patients, regardless of the type of procedure.

Development and evaluation of the accuracy of an indicator of the appropriateness of interventional cardiology generated from a French registry

Background

Development of appropriateness indicators of medical interventions has become a major quality-of-care issue, especially in the domain of interventional cardiology (IC). The objective of this study was to develop and evaluate the accuracy of an indicator of the appropriateness of interventional cardiology acts (invasive coronary angiographies (ICA) and percutaneous coronary interventions (PCI)) in patients with coronary stable disease and silent ischemia, automated from a French registry.

Methods

All ICA and PCI recorded in a Regional IC Registry (ACIRA) and operated for a stable coronary artery disease or silent ischemia from January 1st to December 31th 2013 in eight IC hospitals of Aquitaine, southwestern France, were included.

The indicator was developed to reflect European guidelines. Classification of appropriateness by the indicator, measured on the registry database, was compared to the classification of a reference standard (expert judgment applied through complete record review) on a random sample of 300 interventions.

Accuracy parameters were estimated. A second version of the indicator was defined, based on the analysis of false negative and positive results, and its accuracy estimated.

Results

The second indicator accuracy was: sensitivity 63.5% (95% confidence interval CI [51.7–75.3]), specificity 76.0% (95%CI [70.4–81.6]), PPV 43.0% (95% CI [33.0–53.0]) and NPV 88.0% (95% CI [83.4–92.6]). When stratified on the type of act, parameters were better for ICA alone than for PCI.

Conclusions

Accuracy of the indicator should raise with improvement of database quality. Despite its average accuracy, it is already used as a benchmark indicator for cardiologists. It is sent annually to each IC center with value of the indicator at the region level to allow a comparison.

Temporary Rise in Blood Thrombogenicity in Patients with Acute Myocardial Infarction

Objective  Although blood thrombogenicity seems to be one of the determinant factors for the development of acute myocardial infarction (MI), it has not been dealt with in-depth. This study aimed to investigate blood thrombogenicity and its change in acute MI patients. Methods and Results  We designed a prospective, observational study that included 51 acute MI patients and 83 stable coronary artery disease (CAD) patients who underwent cardiac catheterization, comparing thrombogenicity of the whole blood between: (1) acute MI patients and stable CAD patients; and (2) acute and chronic phase in MI patients. Blood thrombogenicity was evaluated by the Total Thrombus-Formation Analysis System (T-TAS) using the area under the flow pressure curve (AUC ₃₀ ) for the AR-chip. Acute MI patients had significantly higher AUC ₃₀ than stable CAD patients (median [interquartile range], 1,771 [1,585-1,884] vs. 1,677 [1,527-1,756], p  = 0.010). Multivariate regression analysis identified acute MI with initial TIMI flow grade 0/1 as an independent determinant of high AUC ₃₀ ( β  = 0.211, p  = 0.013). In acute MI patients, AUC ₃₀ decreased significantly from acute to chronic phase (1,859 [1,550-2,008] to 1,521 [1,328-1,745], p  = 0.001). Conclusion  Blood thrombogenicity was significantly higher in acute MI patients than in stable CAD patients. Acute MI with initial TIMI flow grade 0/1 was significantly associated with high blood thrombogenicity by multivariate analysis. In acute MI patients, blood thrombogenicity was temporarily higher in acute phase than in chronic phase.

"ST-elevation myocardial infarction associated with air pollution levels in Mexico City"

Background Coronary heart disease has multiple risk factors, including air pollution. Numerous pathophysiological mechanisms have been identified with increasing levels of air pollution, mainly with ozone (O3), nitrogen dioxide (NO2), sulphur dioxide (SO2), particulate matter (PM10), fine particulate matter (PM2.5) and carbon monoxide (CO). In Mexico, the pollution level is reported using an air quality index called IMECA. Methods All patients with STEMI admitted at Hospital Español were collected between 2012 and 2019 (N = 348). We conducted a retrospective analysis using the air pollution exposure at the time of each event (lag0), the previous 24 h (lag1), 48 h (lag2), 72 h (lag3) and 5-day cumulative lag. The level of air pollution was analyzed independently using IMECA and particle concentrations. The data was divided in two groups: days with one of more STEMI’s (MI group) and days free of events (Control group), using ANCOVA to evaluate the difference between means of both groups taking into account confounders. Results: For days with one or more cardiovascular event, a significant increase in SO2 was observed at lag1; similar increase was found in CO, PM2.5, SO2 at lag2. For the 5-day cumulative lag, SO2 and PM2.5 showed a significant increase. No differences were found using the IMECA levels in both groups. Conclusions: The elevated concentrations levels of CO, SO2 and PM2.5 showed significant association with STEMI at different time points before the event. Ozone, PM10 and NO2 showed no difference between groups. IMECA levels showed no association with STEMI in our study.

Effects of Asian dust-derived particulate matter on ST-elevation myocardial infarction: retrospective, time series study

Background

Dust storms affect human health by impairing visibility and promoting interactions with microscopic organisms, such as bacteria and fungi. Although ST-elevation MI (STEMI) and non-ST-elevation MI (NSTEMI) differ mechanistically, few studies have investigated the incidence of cardiovascular diseases according to infarction type; these studies have yielded inconsistent findings. This study aimed to examine whether PM size (< 2.5 μm (PM_2.5) and < 10 μm (PM₁₀)) modifies the effect of Asian dust on acute myocardial infarction (AMI), with separate analyses for STEMI and NSTEMI.

Methods

MI-related data from 9934 emergency visits were collected from the Korea AMI Registry from 2005 to 2017. Asian dust events were defined as days with visibility of ≤10 km. Generalized linear models were used to analyze data with natural cubic splines. To examine potential modifiers, analyses were stratified by age, smoking status, and body mass index (BMI).

Results

No significant associations were observed between Asian dust and AMI. By adjusting for different lag structures, a significant effect was exclusively observed in STEMI. For moving average lags, the largest value at lag 5 (relative risk [RR] 1.083; 95% confidence interval [CI], 1.007–1.166) for single and lags 0–7 (RR 1.067; 95% CI: 1.002–1.136) was observed for PM_2.5; for PM₁₀, the largest significant effect was observed at lag 4 (RR 1.075; 95% CI: 1.010–1.144) for single and lags 0–7 (RR 1.067; 95% CI: 1.002–1.136). RRs were significantly higher in < 65-year-olds than in ≥65-year-olds. Additionally, RRs between the BMI < 25 and BMI ≥ 25 groups were not different; statistically significant effects were observed for concentration at lags 0–5 (RR: 1.073; 95% CI: 1.002–1.150) and lags 0–6 (RR: 1.071; 95% CI: 1.001–1.146) in the BMI < 25 group. A negative exposure-response association was observed between daily average visibility-adjusted PM and STEMI and daily average visibility-adjusted PM in < 65-year-olds.

Conclusions

Reducing PM_2.5 and PM₁₀ emissions, particularly during the days of Asian dust, may be crucial and reduce STEMI and AMI incidence among < 65-year-olds. These results indicate that the Asian dust alarm system needs revision to protect vulnerable populations.

Prognostic impact of high sensitive troponin in predicting 30-day mortality among patients admitted to hospital with influenza

Background

Worldwide, seasonal influenza causes significant mortality and severe infections may cause cardiac injury. High-sensitive-troponins (hsTnT) are sensitive and specific markers of myocardial damage. This study investigated the prognostic impact of hsTnT on 30-day mortality in hospitalised influenza patients.

Methods

This retrospective study included influenza patients ≥ 18 years, who had hsTnT performed during admission in two tertiary-hospitals in South Australia. Diagnosis of influenza was confirmed by polymerase–chain-reaction (PCR) test and hsTnT > 14 ng/L with a change of > 20% during admission was considered to be indicative of acute-cardiac injury. Clinical characteristics, complications and 30-day mortality were compared among four groups of patients: hsTnT unavailable, hsTnT negative, chronically elevated hsTnT and acutely elevated hsTnT. Cox-proportional hazard regression determined the hazard of death at 30-days following hospital discharge after adjustment for co-variates.

Results

Between January 2016 -March 2020, 1828 influenza patients, mean age 66.4 years, were hospitalised. Troponin results were available for 617 (47.7%) patients, of whom, 62 (10%) had acute myocardial injury and 232 (37.6%) had chronic hsTnT elevation. Both inpatient and 30-day mortality were significantly higher among patients with acute (P < 0.001) and chronic hsTnT (P < 0.001) when compared to other groups. When compared to patients with negative hsTnT, acute but not chronic hsTnT elevation was significantly associated with 30-day mortality after adjustment for various co-variates (HR 8.30, 1.80–17.84, P value = 0.013).

Conclusions

This is the largest available analysis of cardiac-specific biomarker hsTnT in patients with influenza. An acutely elevated hsTnT was associated with 30-day mortality among hospitalised influenza patients.

Incidence, delays, and outcomes of STEMI during COVID-19 outbreak: Analysis from the France PCI registry

Objectives

The aim of this study was to assess the impact of the coronavirus disease 2019 (COVID‐19) outbreak on incidence, delays, and outcomes of ST‐elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI) in France.

Methods

We analyzed all patients undergoing PPCI <24 hours STEMI included in the prospective France PCI registry. The 2 groups were compared on mean monthly number of patients, delays in the pathway care, and in‐hospital major adverse cardiac events (MACE: death, stent thrombosis, myocardial infarction, unplanned coronary revascularization, stroke, and major bleeding).

Results

From January 15, 2019 to April 14, 2020, 2064 STEMI patients undergoing PPCI were included: 1942 in the prelockdown group and 122 in the lockdown group. Only 2 cases in the lockdown group were positive for COVID‐19. A significant drop (12%) in mean number of STEMI/month was observed in the lockdown group compared with prelockdown (139 vs 122, P < 0.04). A significant increase in “symptom onset to first medical contact” delay was found for patients who presented directly to the emergency department (ED) (238 minutes vs 450 minutes; P = 0.04). There were higher rates of in‐hospital MACE (7.7% vs 12.3%; P = 0.06) and mortality (4.9% vs 8.2%; P = 0.11) in the lockdown group but the differences were not significant.

Conclusion

According to the multicenter France PCI registry, the COVID‐19 outbreak in France was associated with a significant decline in STEMI undergoing PPCI and longer transfer time for patients who presented directly to the ED. Mortality rates doubled, but the difference was not statistically significant.

[COVID-19 and STEMI]

The COVID-19 pandemic had an unexpected impact on cardiovascular emergencies, particularly STEMI. The France PCI registry and other studies around the world have highlighted a significant decrease in myocardial infarctions arriving at hospital. This decrease is mainly related to patients' fear of coming to the hospital and being contaminated. Although the STEMI revascularisation time targets (<120min) are often difficult to achieve in normal times, they were almost impossible to achieve in periods of lockdown because of the many obstacles. Longer delays and longer total ischemic time have led to excess mortality, especially in the regions most affected by the epidemic. Recommendations for the management of STEMI during the COVID-19 period have thus been issued by the scientific societies. STEMI in patients with COVID-19 often have an uncommon clinical presentation, and the absence of coronary obstruction on angiography is frequent. Their prognosis is very poor. Only public information campaigns and an organisation adapted to the management of coronary emergencies during epidemics can try to limit their effects and avoid aggravating an already fragile health situation in the future.

Short-term exposure to carbon monoxide and myocardial infarction: A systematic review and meta-analysis

BACKGROUND

Previous studies suggest an association between short-term exposure to carbon monoxide and myocardial infarction. We performed a systematic review and meta-analysis to assess current evidence on this association to support the update of the World Health Organization (WHO) Global Air Quality Guidelines.

METHODS

We searched Medline, Embase and Cochrane Central Register of Controlled Trials to update the evidence published in a previous systematic review up to 30th September 2018 for studies investigating the association between short-term exposure to ambient carbon monoxide (up to lag of seven days) and emergency department visits or hospital admissions and mortality due to myocardial infarction. Two reviewers assessed potentially eligible studies and performed data extraction independently. Random-effects meta-analysis was used to derive the pooled risk estimate per 1 mg/m³ increase in ambient carbon monoxide concentration. Risk of bias in individual studies was assessed using a domain-based assessment tool. The overall certainty of the body of evidence was evaluated using an adapted certainty of evidence assessment framework.

RESULTS

We evaluated 1,038 articles from the previous review and our updated literature search, of which, 26 satisfied our inclusion criteria. Overall, myocardial infarction was associated with exposure to ambient carbon monoxide concentration (risk ratio of 1.052, 95% confidence interval 1.017-1.089 per 1 mg/m³ increase). A third of studies were assessed to be at high risk of bias (RoB) due to inadequate adjustment for confounding. Using an adaptation of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework, the overall evidence was assessed to be of moderate certainty.

CONCLUSIONS

This review demonstrated that the pooled risk ratio for myocardial infarction was 1.052 (95% CI 1.017-1.089) per 1 mg/m³ increase in ambient carbon monoxide concentration. However, very few studies originated from low- and middle-income countries.

Transient increase in blood thrombogenicity may be a critical mechanism for the occurrence of acute myocardial infarction

Although the mechanism for the occurrence of acute myocardial infarction (MI) has been investigated by many pathological and clinical studies, it has not been adequately clarified yet. Although the disruption of vulnerable plaque is a well-known cause of acute MI, there are many silent plaque disruptions detected in the coronary artery by intravascular imaging studies. Therefore, many vulnerable plaques may disrupt and heal without causing acute MI. Some additional mechanisms other than the disruption of vulnerable plaque would be essential for the onset of acute MI. On the other hand, blood thrombogenicity would change dynamically due to circadian rhythms and many other factors. The combination of plaque and blood thrombogenicity would play an important and determinant role for the onset of acute MI.

Acute Coronary Syndromes and Covid-19: Exploring the Uncertainties

Since an association between myocardial infarction (MI) and respiratory infections has been described for influenza viruses and other respiratory viral agents, understanding possible physiopathological links between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and acute coronary syndromes (ACS) is of the greatest importance. The initial data suggest an underestimation of ACS cases all over the world, but acute MI still represents a major cause of morbidity and mortality worldwide and should not be overshadowed during the coronavirus disease (Covid-19) pandemic. No common consensus regarding the most adequate healthcare management policy for ACS is currently available. Indeed, important differences have been reported between the measures employed to treat ACS in China during the first disease outbreak and what currently represents clinical practice across Europe and the USA. This review aims to discuss the pathophysiological links between MI, respiratory infections, and Covid-19; epidemiological data related to ACS at the time of the Covid-19 pandemic; and learnings that have emerged so far from several catheterization labs and coronary care units all over the world, in order to shed some light on the current strategies for optimal management of ACS patients with confirmed or suspected SARS-CoV-2 infection.

Systematic review and meta-analysis of case-crossover and time-series studies of short term outdoor nitrogen dioxide exposure and ischemic heart disease morbidity

BACKGROUND

Nitrogen dioxide (NO₂) is a pervasive urban pollutant originating primarily from vehicle emissions. Ischemic heart disease (IHD) is associated with a considerable public health burden worldwide, but whether NO₂ exposure is causally related to IHD morbidity remains in question. Our objective was to determine whether short term exposure to outdoor NO₂ is causally associated with IHD-related morbidity based on a synthesis of findings from case-crossover and time-series studies.

METHODS

MEDLINE, Embase, CENTRAL, Global Health and Toxline databases were searched using terms developed by a librarian. Screening, data extraction and risk of bias assessment were completed independently by two reviewers. Conflicts between reviewers were resolved through consensus and/or involvement of a third reviewer. Pooling of results across studies was conducted using random effects models, heterogeneity among included studies was assessed using Cochran's Q and I² measures, and sources of heterogeneity were evaluated using meta-regression. Sensitivity of pooled estimates to individual studies was examined using Leave One Out analysis and publication bias was evaluated using Funnel plots, Begg's and Egger's tests, and trim and fill.

RESULTS

Thirty-eight case-crossover studies and 48 time-series studies were included in our analysis. NO₂ was significantly associated with IHD morbidity (pooled odds ratio from case-crossover studies: 1.074 95% CI 1.052-1.097; pooled relative risk from time-series studies: 1.022 95% CI 1.016-1.029 per 10 ppb). Pooled estimates for case-crossover studies from Europe and North America were significantly lower than for studies conducted elsewhere. The high degree of heterogeneity among studies was only partially accounted for in meta-regression. There was evidence of publication bias, particularly for case-crossover studies. For both case-crossover and time-series studies, pooled estimates based on multi-pollutant models were smaller than those from single pollutant models, and those based on older populations were larger than those based on younger populations, but these differences were not statistically significant.

CONCLUSIONS

We concluded that there is a likely causal relationship between short term NO₂ exposure and IHD-related morbidity, but important uncertainties remain, particularly related to the contribution of co-pollutants or other concomitant exposures, and the lack of supporting evidence from toxicological and controlled human studies.

Analysis of weather exposure 7 days before occurrence of ST-segment elevation myocardial infarction

BACKGROUND

Several studies have highlighted the relationship between weather patterns and the occurrence of ST-elevation myocardial infarction (STEMI).

AIM

To evaluate the statistical association between the occurrence of STEMI and meteorological variables over the preceding 7 days.

METHODS

This was a retrospective study, using prespecified data from the ORBI (Breton Regional Observatory on Myocardial Infarction) registry, which includes all consecutive patients hospitalized for STEMI in the geographical area of Brest, France. Over a 7-year period, we compared the number of STEMIs per week with the mean values of meteorological variables over the preceding 7 days.

RESULTS

Overall, 7517 patients with STEMI were recorded in the ORBI registry between January 2009 and January 2016. After exclusion of patients not living in the geographical area of interest, 742 patients were included. The weekly incidence of STEMI ranged from 0 to 7 (median 2, interquartile range 1-3). In the univariate analysis, air temperature (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.005-1.01 per 1°C decrease; P=0.03) and atmospheric pressure (OR 1.03, 95% CI 1.01-1.06 per 1 hPa increase; P=0.008) were associated with the weekly incidence of STEMI. In the multivariable analysis, air temperature (OR 1.06, 95% CI 1.01-1.10 per 1°C decrease; P=0.01), atmospheric pressure (OR 1.05, 95% CI 1.02-1.08 per 1 hPa increase; P<0.001) and duration of humidity>80% (OR 1.09, 95% CI 1.02-1.15 per 1hour increase; P=0.007) in the previous 7 days were associated with the occurrence of STEMI.

CONCLUSIONS

In this specific geographical area, occurrence of STEMI was statistically associated with a decrease in air temperature, an increase in atmospheric pressure and an increase in humidity over the preceding 7-day period.

Prognostic impact of high sensitive Troponin T in patients with influenza virus infection: A retrospective analysis

BACKGROUND

Seasonal influenza is an important cause of morbidity and mortality worldwide and cardiac injuries are dangerous complications of influenza infection. Cardiac troponins are established biomarkers of myocardial damage.

OBJECTIVE

The aim of the study was to assess high sensitive Troponin-T (hsTnT) serum levels as a surrogate parameter of cardiac involvement in influenza patients.

METHODS

Cross-sectional analysis of 264 patients with laboratory-confirmed influenza virus infection. Routine laboratory parameters, hsTNT, and the history of cardiovascular disease were included in the analysis. Assessed prognostic endpoints were inpatient therapy requirement, death < 30 days after hospitalization and acute cardiac events (ACE) defined as myocardial ischemia, heart failure or new arrhythmia requiring therapy.

RESULTS

Eighty-four patients (31.8%) had increased hsTnT at the initial presentation and twenty patients (7.6%) experienced ACE. Patients with ACE had higher hsTnT (p < 0.01) and CRP (p = 0.04) serum levels compared to patients who did not experience ACE. A binary logistic regression model to predict ACE revealed hsTnT (p < 0.01) and CRP (p = 0.01) to significantly influence the odds for ACE. A hsTnT cut-off of 46,4 ng/l was identified as having the best discriminative potential to identify patients with ACE (sensitivity = 0.7, specificity = 0.8).

CONCLUSION

To date, this is the largest available analysis of the specific cardiac marker hsTnT in patients with influenza. A slight elevation of hsTnT is a common feature of patients with influenza, however increased hsTnT also highlights a higher risk for cardiac complications and fatal outcome.

Effects of ambient temperature on myocardial infarction: A systematic review and meta-analysis

Previous studies have suggested that ambient temperature is associated with the mortality and morbidity of myocardial infarction (MI) although consistency among these investigations is lacking. We performed a meta-analysis to investigate the relationship between ambient temperature and MI. The PubMed, Web of Science, and China National Knowledge Infrastructure databases were searched back to August 31, 2017. The pooled estimates for different temperature exposures were calculated using a random-effects model. The Cochran's Q test and coefficient of inconsistency (I²) were used to evaluate heterogeneity, and the Egger's test was used to assess publication bias. The exposure-response relationship of temperature-MI mortality or hospitalization was modeled using random-effects meta-regression. A total of 30 papers were included in the review, and 23 studies were included in the meta-analysis. The pooled estimates for the relationship between temperature and the relative risk of MI hospitalization was 1.016 (95% confidence interval [CI]: 1.004-1.028) for a 1 °C increase and 1.014 (95% CI: 1.004-1.024) for a 1 °C decrease. The pooled estimate of MI mortality was 1.639 (95% CI: 1.087-2.470) for a heat wave. The heterogeneity was significant for heat exposure, cold exposure, and heat wave exposure. The Egger's test revealed potential publication bias for cold exposure and heat exposure, whereas there was no publication bias for heat wave exposure. An increase in latitude was associated with a decreased risk of MI hospitalization due to cold exposure. The association of heat exposure and heat wave were immediate, and the association of cold exposure were delayed. Consequently, cold exposure, heat exposure, and exposure to heat waves were associated with an increased risk of MI. Further research studies are required to understand the relationship between temperature and MI in different climate areas and extreme weather conditions.

Triggering of acute myocardial infarction by respiratory infection

BACKGROUND

Respiratory infection has been associated with an increased short-term risk of myocardial infarction (MI). However, previous studies have predominantly been conducted without angiographic confirmation of MI. The possibility can therefore not be excluded that raised troponin levels or electrocardiogram abnormalities that may be seen with respiratory infections are due to non-ischaemic causes.

AIMS

To investigate the association between respiratory infection and angiographically confirmed MI.

METHODS

Interviews were conducted within 4 days of hospitalisation in 578 patients with angiographically confirmed MI, to assess for recent exposure to respiratory infection symptoms and the usual annual frequency of these symptoms. Using case-crossover methodology, exposure to respiratory infection prior to the onset of MI was compared against the usual frequency of exposure in the past year.

RESULTS

Symptoms of respiratory infection were reported by 100 (17%) and 123 (21%) within 7 and 35 days, respectively, prior to MI. The relative risk (RR) for MI occurring within 1-7 days after respiratory infection symptoms was 17.0 (95% confidence interval (CI) 13.2-21.8), and declined with subsequent time periods. In a subgroup analysis, the RR tended to be lower in groups taking regular cardiac medications. For those who reported milder, upper respiratory tract infection symptoms, the RR for the 1-7-day time period was 13.5 (95% CI 10.2-17.7).

CONCLUSION

These findings confirm that respiratory infection can trigger MI. Further study is indicated to identify treatment strategies to decrease this risk, particularly in individuals who may have increased susceptibility.

Short-term exposure to air pollutants increases the risk of ST elevation myocardial infarction and of infarct-related ventricular arrhythmias and mortality

BACKGROUND

The relation between STEMI and air pollution (AP) is scant. We aimed to investigate the short term association between AP and the incidence of STEMI, and STEMI-related ventricular arrhythmias (VA) and mortality.

METHODS

The study was carried out in the area of Barcelona from January 2010 to December 2011. Daily STEMI rates and incidence of STEMI-related VA and mortality were obtained prospectively. The corresponding daily levels of the main pollutants were recorded as well as the atmospheric variables. Three cohorts were defined in order to minimize exposure bias. The magnitude of association was estimated using a time-series design and was adjusted according to atmospheric variables.

RESULTS

The daily rate of hospital admissions for STEMI was associated with increases in PM 2.5, PM 10, lead and NO2 concentrations. VA incidence and mortality were associated with increases in PM 2.5 and PM 10 concentrations. In the most specific cohort, BCN (Barcelona) Attended & Resident, STEMI incidence was associated with increases in PM 2.5 (1.009% per 10μg/m³) and PM 10 concentrations (1.005% per 10μg/m³). VA was associated with increases in PM 2.5 (1.021%) and PM 10 (1.015%) and mortality was associated with increases in PM 2.5 (1.083%) and PM 10 (1.045%).

CONCLUSIONS

Short-term exposure to high levels of PM 2.5 and PM 10 is associated with increased daily STEMI admissions and STEMI-related VA and mortality. Exposure to high levels of lead and NO2 is associated with increased daily STEMI admissions, and NO2 with higher mortality in STEMI patients.

Time-Course Reduction in Patient Exposure to Radiation From Coronary Interventional Procedures

Background—

The frequency of complex percutaneous coronary interventions (PCIs) has increased in the last few years, with a growing concern on the radiation dose received by the patients. Multicenter data from large unselected populations on patients’ radiation doses during coronary angiography (CA) and PCI and temporal trends are lacking. This study sought to evaluate the temporal trends in patients’ exposure to radiation from CA and PCI.

Methods and Results—

Data were taken from the CARDIO-ARSIF registry that prospectively collects data on all CAs and PCIs performed in the 36 catheterization laboratories in the Greater Paris Area, the most populated regions in France with about 12 million inhabitants. Kerma area product and Fluoroscopy time from 152 684 consecutive CAs and 103 177 PCIs performed between 2009 and 2013 were analyzed. A continuous trend for a decrease in median [interquartile range] Kerma area product was observed, from 33 [19–55] Gy cm 2 in 2009 to 27 [16–44] Gy cm 2 in 2013 for CA ( P <0.0001), and from 73 [41–125] to 55 [31–91] Gy cm 2 for PCI ( P <0.0001). Time-course differences in Kerma area product remained highly significant after adjustment on Fluoroscopy time, PCI procedure complexity, change of x-ray equipment, and other patient- and procedure-related covariates.

Conclusions—

In a large patient population, a steady temporal decrease in patient radiation exposure during CA and PCI was noted between 2009 and 2013. Kerma area product reduction was consistent in all types of procedure and was independent of patient-related factors and PCI procedure complexity.

Air pollution and ST-elevation myocardial infarction: A case-crossover study of the Belgian STEMI registry 2009-2013

BACKGROUND

Previous studies have shown that air pollution particulate matter (PM) is associated with an increased risk for myocardial infarction. The effects of air pollution on the risk of ST-elevation myocardial infarction (STEMI), in particular the role of gaseous air pollutants such as NO₂ and O₃ and the susceptibility of specific populations, are still under debate.

METHODS

All patients entered in the Belgian prospective STEMI registry between 2009 and 2013 were included. Based on a validated spatial interpolation model from the Belgian Environment Agency, a national index was used to address the background level of air pollution exposure of Belgian population. A time-stratified and temperature-matched case-crossover analysis of the risk of STEMI was performed.

RESULTS

A total of 11,428 STEMI patients were included in the study. Each 10μg/m³ increase in PM10, PM2.5 and NO₂ was associated with an increased odds ratio (ORs) of STEMI of 1.026 (CI _95%: 1.005-1.048), 1.028 (CI _95%: 1.003-1.054) and 1.051 (CI _95%: 1.018-1.084), respectively. No effect of O₃ was found. STEMI was associated with PM10 exposure in patients ≥75y.o. (OR: 1.046, CI _95%: 1.002-1.092) and with NO₂ in patients ≤54y.o. (OR: 1.071, CI _95%: 1.010-1.136). No effect of air pollution on cardiac arrest or in-hospital STEMI mortality was found.

CONCLUSION

PM2.5 and NO₂ exposures incrementally increase the risk of STEMI. The risk related to PM appears to be greater in the elderly, while younger patients appear to be more susceptible to NO₂ exposure.

Acute cardiac injury events ≤30 days after laboratory-confirmed influenza virus infection among U.S. veterans, 2010-2012

BACKGROUND

Cardiac injury is a known potential complication of influenza infection. Because U.S. veterans cared for at the U.S. Department of Veterans Affairs are older and have more cardiovascular disease (CVD) risk factors than the general U.S. population, veterans are at risk for cardiac complications of influenza infection. We investigated biomarkers of cardiac injury characteristics and associated cardiac events among veterans who received cardiac biomarker testing ≤30 days after laboratory-confirmed influenza virus infection.

METHODS

Laboratory-confirmed influenza cases among veterans cared for at U.S. Department of Veterans Affairs' facilities for October 2010-December 2012 were identified using electronic medical records (EMRs). Influenza confirmation was based on respiratory specimen viral culture or antigen or nucleic acid detection. Acute cardiac injury (ACI) was defined as an elevated cardiac biomarker (troponin I or creatinine kinase isoenzyme MB) >99 % of the upper reference limit occurring ≤30 days after influenza specimen collection. EMRs were reviewed for demographics, CVD history and risk factors, and ACI-associated cardiac events.

RESULTS

Among 38,197 patients with influenza testing results, 4,469 (12 %) had a positive result; 600 of those patients had cardiac biomarker testing performed ≤30 days after influenza testing, and 143 (24 %) had one or more elevated cardiac biomarkers. Among these 143, median age was 73 years (range 44-98 years), and 98 (69 %) were non-Hispanic white. All patients had one or more CVD risk factors, and 98 (69 %) had a history of CVD. Eighty-six percent of ACI-associated events occurred within 3 days of influenza specimen collection date. Seventy patients (49 %) had documented or probable acute myocardial infarction, 8 (6 %) acute congestive heart failure, 6 (4 %) myocarditis, and 4 (3 %) atrial fibrillation. Eleven (8 %) had non-cardiac explanations for elevated cardiac biomarkers, and 44 (31 %) had no documented explanation. Sixty-eight (48 %) patients had received influenza vaccination during the related influenza season.

CONCLUSION

Among veterans with laboratory-confirmed influenza infection and cardiac biomarker testing ≤30 days after influenza testing, approximately 25 % had evidence of ACI, the majority within 3 days. Approximately half were myocardial infarctions. Our findings emphasize the importance of considering ACI associated with influenza infection among patients at high risk, including this older population with prevalent CVD risk factors.

[Do weather and seasons influence our heart?]

There are numerous publications about impact of meteo, seasons and pollution on cardiovascular diseases. Cardiovascular diseases, in particular myocardial infarction and heart failure, have been consistently more frequent during winter in the northern and southern hemisphere. Chronic exposure to air pollution influences the development of atherosclerosis and increases the risk for coronary artery disease. There is a positive association between short-term increase in gaseous components with the risk of hospitalization or death from congestive heart failure. The considerable impact on health care service warrants a comprehensive approach to cardiovascular disease management.