Comparative outcomes in patients with preexisting heart failure to those without heart failure after out-of-hospital cardiac arrest: A nationwide registry study.

BACKGROUND: The knowledge of prognosis following out-of-hospital cardiac arrest (OHCA) in patients with heart failure heart failure (HF) is sparse. The objective of this study was to compare the outcome after OHCA among patients with and without HF. METHODS: We studied 45,293 patients who were included for the Danish cardiac arrest registry between 2001 and 2014. Patients were stratified into two groups based on the presence of HF prior to cardiac arrest. The primary outcome was 30-day survival and secondary outcome was anoxic brain damage or permanent nursing home admission at 1-year among 30-day survivors. RESULTS: Among the final 28,955 patients included, 6675 (23%) patients had prior HF and 22,280 (77%) patients had no prior HF. At 30 days, 616 (9.2%) patients survived among the patients with HF and 1916 (8.6%) among the patients without HF. There was a significant interaction between atrial fibrillation (AF) and HF for primary outcome and therefore it was assessed separately between the two study groups stratified based on AF. Among patients without AF a significantly higher odds of 30-day survival were observed among patients with HF (OR 2.69, 95% CI 2.34-3.08, P < 0.001), but no difference was observed among the patients from two study groups with no AF. No significant difference in risk for secondary outcome was observed among the two study groups. In multivariable average treatment effect modeling, all the results largely remain unchanged. CONCLUSIONS: Outcome following OHCA among patients with and without HF is found to be similar in this large Danish OHCA registry.

Performance of 8- vs 16 ECG-gated reconstructions in assessing myocardial function using Rubidium-82 myocardial perfusion imaging: Findings in a young, healthy population.

BACKGROUND: Current imaging guidelines recommend using at least 16 ECG gates when performing MUGA and cardiac SPECT to assess left ventricular ejection fraction (LVEF). However, for Rubidium-82 (82Rb) PET, 8 ECG-gated reconstructions have been a mainstay. This study investigated the implications of quantitative assessments when employing 16 gate, instead of 8 gate, reconstructions for 82Rb myocardial perfusion imaging (MPI). METHODS: The study comprised 25 healthy volunteers (median age 23 years) who underwent repeat MPI sessions employing 82Rb PET/CT. We report LVEF, its reserve (stress LVEF - rest LVEF), and their repeatability measures (RMS method) obtained for 8- and 16 ECG-gated reconstructions. RESULTS: Similar LVEF and LVEF reserve estimates were found for the 8- and 16-gated reconstructions ([%] LVEF (8/16 gates): rest = 61 ± 6/64 ± 6, stress = 68 ± 7/71 ± 6, LVEF reserve (8/16 gates): 8 ± 3/6 ± 4, and all P ≥ 0.13). Similar test-retest repeatability measures were observed for rest and stress LVEF and their reserves [LVEF (8/16 gates); Rest = 4.5/4.6 (P = 0.81), Stress = 3.5/3.2 (P = 0.33), LVEF reserve = 46.7/49.3 (P = 0.13)]. CONCLUSION: In healthy subjects, 8 and 16 ECG gates can be used interchangeably if only volumetric assessments are desired. However, if filling and emptying rates are of interest, a minimum of 16 ECG gates should be employed.

Duration of resuscitation and long-term outcome after in-hospital cardiac arrest: A nationwide observational study.

BACKGROUND: Prior studies have investigated the association between duration of resuscitation and short-term outcomes following in-hospital cardiac arrest (IHCA). However, it remains unknown whether there is an association between duration of resuscitation and long-term survival and functional outcomes. METHOD: We linked data from the Danish in-hospital cardiac arrest registry with nationwide registries and identified 8,727 patients between 2013 and 2019. Patients were stratified into four groups (A-D) according to quartiles of duration of resuscitation. Standardized average probability of outcomes was estimated using logistic regression. RESULTS: Of 8,727 patients, 53.1% (n = 4,604) achieved return of spontaneous circulation. Median age was 74 (1st-3rd quartile [Q1-Q3] 65-81 years) and 63.1% were men. Among all IHCA patients the standardized 30-day survival was 62.0% (95% CI 59.8-64.2%) for group A (<5 minutes), 32.7% (30.8-34.6%) for group B (5-11 minutes), 14.4% (12.9-15.9%) for group C (12-20 minutes) and 8.1% (7.0-9.1%) for group D (21 minutes or more). Similarly, 1-year survival was also highest for group A (50.4%; 48.2-52.6%) gradually decreasing to 6.6% (5.6-7.6%) in group D. Among 30-day survivors, survival without anoxic brain damage or nursing home admission within one-year post-arrest was highest for group A (80.4%; 78.2-82.6%), decreasing to 73.3% (70.0-76.6%) in group B, 67.2% (61.7-72.6%) in group C and 73.3% (66.9-79.7%) in group D. CONCLUSION: Shorter duration of resuscitation attempt during an IHCA is associated with higher 30-day and 1-year survival. Furthermore, we found that the majority of 30-day survivors were still alive 1-year post-arrest without anoxic brain damage or nursing home admission despite prolonged resuscitation.

External validation of the simple NULL-PLEASE clinical score in predicting outcomes of out-of-hospital cardiac arrest in the Danish population - A nationwide registry-based study.

AIM: The NULL-PLEASE score (Nonshockable rhythm, Unwitnessed arrest, Long no-flow or Long low-flow period, blood pH < 7.2, Lactate > 7.0 mmol/L, End-stage renal disease on dialysis, Age ≥85 years, Still resuscitation, and Extracardiac cause) may identify patients with out-of-hospital cardiac arrest (OHCA) unlikely to survive. We aimed to validate the NULL-PLEASE score in a nationwide setting. METHODS: We used Danish nationwide registry data from 2001 to 2019 and identified OHCA survivors with return of spontaneous circulation (ROSC) or ongoing cardiopulmonary resuscitation at hospital arrival. The primary outcome was 1-day mortality. Secondary outcomes were 30-day mortality and the combined outcome of 1-year mortality or anoxic brain damage. The risks of outcomes were estimated using logistic regression with a NULL-PLEASE score of 0 as reference (range 0-14). The predictive ability of the score was examined using the area under the receiver operating characteristics (AUCROC) curve. RESULTS: A total of 3,881 patients were included in the analyses. One-day mortality was 35%, 30-day mortality was 61%, and 68% experienced the combined outcome. For a NULL-PLEASE score ≥9 (n = 244) the absolute risks were: 1-day mortality: 80.7% (95% confidence interval [CI]: 75.8-85.7%); 30-day mortality: 98.0% (95% CI: 96.2-99.7%); and the combined outcome: 98.4% (95% CI: 96.8-100.0%). Corresponding AUCROC values were 0.800 (95% CI: 0.786-0.814) for 1-day mortality, 0.827 (95% CI: 0.814-0.840) for 30-day mortality, and 0.828 (95% CI: 0.815-0.841) for the combined outcome. CONCLUSIONS: In a nationwide OHCA-cohort, AUCROC values for the predictive ability of NULL-PLEASE were high for all outcomes. However, some survived even with high NULL-PLEASE scores.

Optimization of the left ventricle ejection fraction estimate obtained during cardiac adenosine stress 82Rubidium-PET scanning: impact of different reconstruction protocols.

BACKGROUND: Left ventricular ejection fraction (LVEF) estimation using adenosine stress myocardial perfusion imaging (MPI) can be challenging. The short half-life of adenosine and the guideline-recommended adenosine infusion stop during Rubidium-82 acquisition protocol may affect the accuracy and repeatability of the LVEF measures. METHODS: This study comprised 25 healthy volunteers (median age 23 years) who underwent repeat myocardial perfusion imaging (MPI) sessions employing Rubidium-82 PET/CT. A guideline-recommended reconstruction protocol was used for both rest and adenosine stress MPI (150-360 s post-radiotracer injection, standardrecon). For the stress MPI protocol, two additional reconstruction protocols were considered; one was employing 60 seconds data (150-210 seconds, shortfixed) and the other a dynamic frame window based on the bolus arrival of Rubidium-82 in the heart until 210 seconds (x-210 seconds, shortindividual). We report rest and stress LVEF, the LVEF reserve, and the LVEF reserve repeatability. RESULTS: Differences in the LVEF assessments were observed between the guideline recommended and alternative reconstruction protocol (LVEF stress MPI: standardrecon = 68 ± 7%, shortfixed = 71 ± 7% (P = .08), shortindividual = 72 ± 7% (P = .04)), and the LVEF reserve was reduced for the guideline-recommended protocol (standardrecon = 7.8 ± 3.5, shortfixed = 10.1 ± 3.7, shortindividual = 10.5 ± 3.6, all P < .001). The best repeatability measures were obtained for the shortindividual protocol (repeatability: standardrecon = 45.3%, shortfixed = 41.2%, shortindividual = 31.7%). CONCLUSION: We recommend using the shortindividual reconstruction protocol for improved LVEF repeatability and reserve assessment. Alternatively, in centers with limited technical support we recommend the use of the shortfixed protocol.

Image-derived and physiological markers to predict adequate adenosine-induced hyperemic response in Rubidium-82 myocardial perfusion imaging.

AIMS: This study aimed to investigate the potential of different markers to identify adequate stressing in subjects with and without caffeine intake prior to Rubidium-82 myocardial imaging. METHODS AND RESULTS: This study comprised 40 healthy subjects who underwent four serial Rubidium-82 rest/adenosine stress MPI; two with 0mg caffeine consumption (baseline MPIs) and two with controlled consumption of caffeine (arm 1: 100 and 300mg, or arm 2: 200 and 400mg). We report the sensitivity and specificity of seven markers ability to predict adequate adenosine-induced hyperemic response: (1) the splenic response ratio (SRR); (2) splenic stress-to-rest intensity ratios (SIR); (3) changes in heart rate (ΔHR); (4) percentwise change in heart rate (Δ%HR); (5) changes in the rate pressure product (ΔRPP); (6) changes in the systolic blood pressure (ΔSBP); and (7) changes in the cardiovascular resistance (ΔCVR). Adequate stressing was determined as stress myocardial blood flow > 3ml/g/min and a corresponding myocardial flow reserve >68% of the individual maximum myocardial flow reserve obtained in the baseline MPIs. RESULTS: 129 MPI sessions (obtained in 39 subjects) were considered for this study. The following sensitivities were obtained: SSR = 72.7%, SIR = 63.6%, ΔHR = 45.5%, Δ%HR = 77.3%, ΔRPP = 54.5%, ΔSBP = 47.7%, and ΔCVR =40.9%, while the specificities were SSR = 80.9%, SIR = 85.0%, ΔHR = 90.4%, Δ%HR = 81.6%, ΔRPP=81.1%, ΔSBP = 86.4%, and ΔCVR =90.4%. CONCLUSION: The image-derived and physiological markers all provide acceptable sensitivities and specificities when patients follow the caffeine pausation before MPI. However, their use warrants great care when caffeine consumption cannot be ruled out.

Risk of out-of-hospital cardiac arrest in antidepressant drug users.

Conflicting results have been reported regarding the association between antidepressant use and out-of-hospital cardiac arrest (OHCA) risk. We investigated whether the use of antidepressants is associated with OHCA. METHODS: We conducted a nationwide nested case-control study to assess the association of individual antidepressant drugs within drug classes with the hazard of OHCA. Cases were defined as OHCA from presumed cardiac causes. Cox regression with time-dependent exposure and time-dependent covariates was conducted to calculate hazard ratios (HR) and 95% confidence intervals (95% CIs) overall and in subgroups defined by established cardiac disease and cardiovascular risk factors. Also, we studied antidepressants with and without sodium channel blocking or potassium channel blocking properties separately. RESULTS: During the study period from 2001 to 2015 we observed 10 987 OHCA cases, and found increased OHCA rate for high-dose citalopram (>20 mg) and high-dose escitalopram (>10 mg; HR:1.46 [95% CI:1.27-1.69], HR:1.43 [95% CI:1.16-1.75], respectively) among selective serotonin reuptake inhibitors (reference drug sertraline), and for high-dose mirtazapine (>30; HR:1.59 [95% CI:1.18-2.14]) among the serotonin-norepinephrine reuptake inhibitors or noradrenergic and specific serotonergic antidepressants (reference drug duloxetine). Among tricyclic antidepressants (reference drug amitriptyline), no drug was associated with significantly increased OHCA rate. Increased OHCA rate was found for antidepressants with known potassium channel blocking properties (HR:1.14 [95% CI:1.05-1.23]), but for not those with sodium channel blocking properties. Citalopram, although not statistically significant, and mirtazapine were associated with increased OHCA rate in patients without cardiac disease and cardiovascular risk factors. CONCLUSION: Our findings indicate that careful titration of citalopram, escitalopram and mirtazapine dose may have to be considered due to drug safety issues.

Out-of-hospital cardiac arrest and differential risk of cardiac and non-cardiac QT-prolonging drugs in 37 000 cases.

AIMS: Drugs that prolong the QT interval, either by design (cardiac QT-prolonging drugs: anti-arrhythmics) or as off-target effect (non-cardiac QT-prolonging drugs), may increase the risk of ventricular arrhythmias and out-of-hospital cardiac arrest (OHCA). Risk mitigation measures were instituted, in particular, surrounding prescription of cardiac QT-prolonging drugs. We studied OHCA risk of both drug types in current clinical practice. METHODS: Using data from large population-based OHCA registries in the Netherlands and Denmark, we conducted two independent case-control studies. OHCA cases with presumed cardiac causes were matched on age/sex/index date with up to five non-OHCA controls. We calculated odds ratios (ORs) for the association of cardiac or non-cardiac QT-prolonging drugs with OHCA risk using conditional logistic regression analyses. RESULTS: We identified 2503 OHCA cases and 10 543 non-OHCA controls in the Netherlands, and 35 017 OHCA cases and 175 085 non-OHCA controls in Denmark. Compared to no use of QT-prolonging drugs, use of non-cardiac QT-prolonging drugs (Netherlands: cases: 3.0%, controls: 1.9%; Denmark: cases: 14.9%, controls: 7.5%) was associated with increased OHCA risk (Netherlands: OR 1.37 [95% CI: 1.03-1.81]; Denmark: OR 1.63 [95% CI: 1.57-1.70]). The association between cardiac QT-prolonging drugs (Netherlands: cases: 4.0%, controls: 2.5%; Denmark: cases: 2.1%, controls: 0.9%) and OHCA was weaker (Netherlands: OR 1.17 [95% CI: 0.92-1.50]; Denmark: OR 1.21 [95% CI: 1.09-1.33]), although users of cardiac QT-prolonging drugs had more medication use and comorbidities associated with OHCA risk than users of non-cardiac QT-prolonging drugs. CONCLUSION: In clinical practice, cardiac QT-prolonging drugs confer lower OHCA risk than non-cardiac QT-prolonging drugs, although users of the former have higher a priori risk. This is likely due to risk mitigation measures surrounding prescription of cardiac QT-prolonging drugs.

Sex Differences and Caffeine Impact in Adenosine-Induced Hyperemia.

Caffeine consumption before adenosine stress myocardial perfusion imaging (MPI) is known to affect the hemodynamic response and, thus, reduce the stress myocardial blood flow (MBF) and myocardial flow reserve (MFR) assessments. However, it is not clear if any sex-specific differences in the hemodynamic response after caffeine consumption exist. This study aimed to evaluate if such differences exist and, if so, their impact on MBF and MFR assessments. Methods: This study comprised 40 healthy volunteers (19 women). All volunteers underwent 4 serial rest/stress MPI sessions using 82Rb; 2 sessions were acquired without controlled caffeine consumption, and 2 sessions after oral ingestion of either 100 and 300 mg of caffeine or 200 and 400 mg of caffeine. For the caffeine imaging sessions, caffeine was ingested orally 1 h before the MPI scan. Results: Increase in plasma caffeine concentration (PCC) (mg/L) after consumption of caffeine was larger in women (MPI session without caffeine vs. MPI session with caffeine: women = 0.3 ± 0.2 vs. 5.4 ± 5.1, men = 0.1 ± 0.2 vs. 2.7 ± 2.6, both P < 0.001). Caffeine consumption led to reduced stress MBF and MFR assessments for men whereas no changes were reported for women (women [PCC < 1 mg/L vs. PCC ≥ 1 mg/L]: stress MBF = 3.3 ± 0.6 vs. 3.0 ± 0.8 mL/g/min, P = 0.07; MFR = 3.7 ± 0.6 vs. 3.5 ± 1.0, P = 0.35; men [PCC < 1 mg/L vs. PCC ≥ 1 mg/L]: stress MBF = 2.7 ± 0.7 vs. 2.1 ± 1.0 mL/g/min, P = 0.005; MFR = 3.8 ± 1.0 vs. 3.1 ± 1.4, P = 0.018). Significant differences in the stress MBF were observed for the 2 sexes (both P ≤ 0.001), whereas similar MFR was reported (both P ≥ 0.12). Conclusion: Associations between increases in PCC and reductions in stress MBF and MFR were observed for men, whereas women did not have the same hemodynamic response. Stress MBF was affected at lower PCCs in men than women.

Opioid use is associated with increased out-of-hospital cardiac arrest risk among 40 000-cases across two countries.

AIMS: Opioid use has substantially increased in the last decade and is associated with overdose mortality, but also with increased mortality from cardiovascular causes. This finding may partly reflect an association between opioids and out-of-hospital cardiac arrest (OHCA). Therefore, we aimed to investigate OHCA-risk of opioids in the community. METHODS: We conducted 2 population-based case-control studies separately in the Netherlands (2009-2018) and Denmark (2001-2015). Cases were individuals who experienced OHCA of presumed cardiac cause. Each case was matched with up to 5 non-OHCA-controls according to age, sex and OHCA-date. Conditional logistic regression analysis was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: We included 5473 OHCA-cases matched with 21 866 non-OHCA-controls in the Netherlands, and 35 017 OHCA-cases matched with 175 085 non-OHCA-controls in Denmark. We found that use of opioids (the Netherlands: cases: 5.4%, controls: 1.8%; Denmark: cases: 11.9%, controls: 4.4%) was associated with increased OHCA-risk in both regions (the Netherlands: OR 2.1 [95% CI 1.8-2.5]; Denmark: OR 1.8 [95% CI 1.5-2.1]). The association was observed in both sexes, and in individuals with cardiovascular disease (the Netherlands: OR 1.8 [95% CI 1.5-2.1]; Denmark: OR 1.6 [95% CI 1.5-1.7]) or without (the Netherlands: OR 3.4 [95% CI: 2.4-4.8], Pinteraction  < .0001; Denmark: OR 2.3 [95% CI: 2.0-2.5], Pinteraction  < .0001). CONCLUSION: Use of opioids is associated with increased OHCA-risk in both sexes, independently of concomitant cardiovascular disease. These findings should be considered when evaluating the harms and benefits of treatment with opioids.

Contacts With the Health Care System Before Out-of-Hospital Cardiac Arrest.

Background It remains challenging to identify patients at risk of out-of-hospital cardiac arrest (OHCA). We aimed to examine health care contacts in patients before OHCA compared with the general population that did not experience an OHCA. Methods and Results Patients with OHCA with a presumed cardiac cause were identified from the Danish Cardiac Arrest Registry (2001-2014) and their health care contacts (general practitioner [GP]/hospital) were examined up to 1 year before OHCA. In a case-control study (1:9), OHCA contacts were compared with an age- and sex-matched background population. Separately, patients with OHCA were examined by the contact type (GP/hospital/both/no contact) within 2 weeks before OHCA. We included 28 955 patients with OHCA. The weekly percentages of patient contacts with GP the year before OHCA were constant (25%) until 1 week before OHCA when they markedly increased (42%). Weekly percentages of patient contacts with hospitals the year before OHCA gradually increased during the last 6 months (3.5%-6.6%), peaking at the second week (6.8%) before OHCA; mostly attributable to cardiovascular diseases (21%). In comparison, there were fewer weekly contacts among controls with 13% for GP and 2% for hospital contacts (P<0.001). Within 2 weeks before OHCA, 57.8% of patients with OHCA had a health care contact, and these patients had more contacts with GP (odds ratio [OR], 3.17; 95% CI, 3.09-3.26) and hospital (OR, 2.32; 95% CI, 2.21-2.43) compared with controls. Conclusions The health care contacts of patients with OHCA nearly doubled leading up to the OHCA event, with more than half of patients having health care contacts within 2 weeks before arrest. This could have implications for future preventive strategies.

Increased 5-year risk of stroke, atrial fibrillation, acute coronary syndrome, and heart failure in out-of-hospital cardiac arrest survivors compared with population controls: A nationwide registry-based study.

AIM: Long-term risks of stroke, atrial fibrillation, or flutter (AF), acute coronary syndrome (ACS), and heart failure (HF) among survivors of out-of-hospital cardiac arrest (OHCA) are unknown. We aimed to examine 5-year risks of these outcomes among 30-day survivors of OHCA. METHODS: Thirty-day survivors of OHCA without a prior (or within 30 days after cardiac arrest) history of stroke, AF, ACS, or HF and population controls without a prior history of these conditions were identified using Danish nationwide registries. Five-year risks of stroke, AF, ACS, and HF standardized to the distributions of age, sex, and comorbidities among OHCA survivors and controls were obtained using multivariable regression. RESULTS: Of 4,362 30-day OHCA-survivors, 1,051 were stroke-, AF-, ACS-, and HF-naïve and matched with controls using age, sex, and time of OHCA event. Absolute five-year risks for OHCA survivors vs. controls were for stroke: 6.3% [95% confidence interval (CI) 4.1-8.5] vs. 2.0% [1.6-2.5], AF: 7.9% [5.7-10.2] vs. 2.6% [2.1-3.1], ACS: 5.0% [3.2-6.8] vs. 1.5% [1.1-1.9], and HF: 12.7% [10.1-15.4] vs. 1.2% [0.9-1.6], respectively. Corresponding relative risks were 3.18 [95% CI 1.76-4.61] for stroke, 3.03 [1.93-4.14] for AF, 3.23 [1.69-4.77] for ACS, and 10.40 [6.57-14.13] for HF. CONCLUSION: When compared with population controls, OHCA survivors had significantly increased five-year risks of incident stroke, AF, ACS, and HF.

Long-term outcomes after out-of-hospital cardiac arrest in relation to socioeconomic status.

AIMS: This study aimed to examine whether socioeconomic differences exist in long-term outcomes after out-of-hospital cardiac arrest (OHCA). METHODS: We included 2309 30-day OHCA survivors ≥ 30 years of age from the Danish Cardiac Arrest Registry, 2001-2014, divided in tertiles of household income (low, medium, high). Absolute probabilities were estimated using logistic regression for 1-year outcomes and cause-specific Cox regression for 5-year outcomes. Differences between income-groups were standardized with respect to age, sex, education and comorbidities. RESULTS: High-income compared to low-income patients had highest 1-year (96.4% vs. 84.2%) and 5-year (87.6% vs. 64.1%) survival, and lowest 1-year (11.3% vs. 7.4%) and 5-year (13.7% vs. 8.6%) risk of anoxic brain damage/nursing home admission. The corresponding standardized probability differences were 8.2% (95%CI 4.7-11.6%) and 13.9% (95%CI 8.2-19.7%) for 1- and 5-year survival, respectively; and -4.5% (95%CI -8.2 to -1.2%) and -5.1% (95%CI -9.3 to -0.9%) for 1- and 5-year risk of anoxic brain damage/nursing home admission, respectively. Among 831 patients < 66 years working prior to OHCA, 72.1% returned to work within 1 year and 80.8% within 5 years. High-income compared to low-income patients had the highest chance of 1-year (76.4% vs. 58.8%) and 5-year (85.3% vs. 70.6%) return to work with the corresponding absolute probability difference of 18.0% (95%CI 3.8-32.7%) for 1-year and 9.4% (95%CI -3.4 to 22.3%) for 5-year. CONCLUSION: Patients of high socioeconomic status had higher probability of long-term survival and return to work, and lower risk of anoxic brain damage/nursing home admission after OHCA compared to patients of low socioeconomic status.

Implications for cardiac arrest coverage using straight-line versus route distance to nearest automated external defibrillator.

AIM: Quantifying the ratio describing the difference between "true route" and "straight-line" distances from out-of-hospital cardiac arrests (OHCAs) to the closest accessible automated external defibrillator (AED) can help correct likely overestimations in AED coverage. Furthermore, we aimed to examine to what extent the closest AED based on true route distance differed from the closest AED using "straight-line". METHODS: OHCAs (1994-2016) and AEDs (2016) in Copenhagen, Denmark and in Toronto, Canada (2007-2015 and 2015, respectively) were identified. Three distances were calculated between OHCA and target AED: 1) the straight-line distance ("straight-line") to the closest AED, 2) the corresponding true route distance to the same AED ("true route"), and 3) the closest AED based only on true route distance ("shortest true route"). The ratio between "true route" and "straight-line" distance was calculated and differences in AED coverage (an OHCA ≤ 100 m of an accessible AED) were examined. RESULTS: The "straight-line" AED coverage of 100 m was 24.2% (n = 2008/8295) in Copenhagen and 6.9% (n = 964/13916) in Toronto. The corresponding "true route" distance reduced coverage to 9.5% (n = 786) and 3.8% (n = 529), respectively. The median ratio between "true route" and "straight-line" distance was 1.6 in Copenhagen and 1.4 in Toronto. In 26.1% (n = 2167) and 22.9% (n = 3181) of all Copenhagen and Toronto OHCAs respectively, the closest AED in "shortest true route" was different than the closest AED initially found by "straight-line". CONCLUSIONS: Straight-line distance is not an accurate measure of distance and overestimates the actual AED coverage compared to a more realistic true route distance by a factor 1.4-1.6.

[Paradox embolism in a patient with pulmonary embolism and unknown patent foramen ovale].

This case report describes a 64-year-old male patient, who presented with sudden onset dyspnoea. A chest CT-angiography revealed the presence of central bilateral pulmonary embolisms (PE), and he was admitted for anticoagulative treatment. Shortly after admission, he developed discomfort and pulselessness in the right leg, and a limb CT-angiography revealed a femoral artery thrombus. PE in conjunction with acute limb ischaemia raised suspicion of a paradoxical mechanism of systemic embolism, which was confirmed by echocardiography with thrombus straddling a patent foramen ovale.

Risk of out-of-hospital cardiac arrest in patients with bipolar disorder or schizophrenia.

OBJECTIVE: Patients with bipolar disorder and schizophrenia are at high cardiovascular risk; yet, the risk of out-of-hospital cardiac arrest (OHCA) compared with the general population remains scarcely investigated. METHODS: We conducted a nested case-control study using Cox regression to assess the association of bipolar disorder and schizophrenia with the HRs of OHCA of presumed cardiac cause (2001-2015). Reported are the HRs with 95% CIs overall and in subgroups defined by established cardiac disease, cardiovascular risk factors and psychotropic drugs. RESULTS: We included 35 017 OHCA cases and 175 085 age-matched and sex-matched controls (median age 72 years and 66.9% male). Patients with bipolar disorder or schizophrenia had overall higher rates of OHCA compared with the general population: HR 2.74 (95% CI 2.41 to 3.13) and 4.49 (95% CI 4.00 to 5.10), respectively. The association persisted in patients with both cardiac disease and cardiovascular risk factors at baseline (bipolar disorder HR 2.14 (95% CI 1.72 to 2.66), schizophrenia 2.84 (95% CI 2.20 to 3.67)) and among patients without known risk factors (bipolar disorder HR 2.14 (95% CI 1.09 to 4.21), schizophrenia HR 5.16 (95% CI 3.17 to 8.39)). The results were confirmed in subanalyses only including OHCAs presenting with shockable rhythm or receiving an autopsy. Antipsychotics-but not antidepressants, lithium or antiepileptics (the last two only tested in bipolar disorder)-increased OHCA hazard compared with no use in both disorders. CONCLUSIONS: Patients with bipolar disorder or schizophrenia have a higher rate of OHCA compared with the general population. Cardiac disease, cardiovascular risk factors and antipsychotics represent important underlying mechanisms.

Socioeconomic disparities in prehospital factors and survival after out-of-hospital cardiac arrest.

OBJECTIVE: It remains unknown whether patient socioeconomic factors affect interventions and survival after out-of-hospital cardiac arrest (OHCA), and whether a socioeconomic effect on bystander interventions affects survival. Therefore, this study examined patient socioeconomic disparities in prehospital factors and survival. METHODS: From the Danish Cardiac Arrest Registry, patients with OHCA ≥30 years were identified, 2001-2014, and divided into quartiles of household income (highest, high, low, lowest). Associations between income and bystander cardiopulmonary resuscitation (CPR) and 30-day survival with bystander CPR as mediator were analysed by logistic regression and mediation analysis in private witnessed, public witnessed, private unwitnessed and public unwitnessed arrests, adjusted for confounders. RESULTS: We included 21 480 patients. Highest income patients were younger, had higher education and were less comorbid relative to lowest income patients. They had higher odds for bystander CPR with the biggest difference in private unwitnessed arrests (OR 1.74, 95% CI 1.47 to 2.05). For 30-day survival, the biggest differences were in public witnessed arrests with 26.0% (95% CI 22.4% to 29.7%) higher survival in highest income compared with lowest income patients. Had bystander CPR been the same for lowest income as for highest income patients, then survival would be 25.3% (95% CI 21.5% to 29.0%) higher in highest income compared with lowest income patients, resulting in elimination of 0.79% (95% CI 0.08% to 1.50%) of the income disparity in survival. Similar trends but smaller were observed in low and high-income patients, the other three subgroups and with education instead of income. From 2002 to 2014, increases were observed in both CPR and survival in all income groups. CONCLUSION: Overall, lower socioeconomic status was associated with poorer prehospital factors and survival after OHCA that was not explained by patient or cardiac arrest-related factors.

Association of beta-blockers and first-registered heart rhythm in out-of-hospital cardiac arrest: real-world data from population-based cohorts across two European countries.

AIMS: Conflicting results have been reported regarding the effect of beta-blockers on first-registered heart rhythm in out-of-hospital cardiac arrest (OHCA). We aimed to establish whether the use of beta-blockers influences first-registered rhythm in OHCA. METHODS AND RESULTS: We included patients with OHCA of presumed cardiac cause from two large independent OHCA-registries from Denmark and the Netherlands. Beta-blocker use was defined as exposure to either non-selective beta-blockers, ß1-selective beta-blockers, or α-ß-dual-receptor blockers within 90 days prior to OHCA. We calculated odds ratios (ORs) for the association of beta-blockers with first-registered heart rhythm using multivariable logistic regression. We identified 23 834 OHCA-patients in Denmark and 1584 in the Netherlands: 7022 (29.5%) and 519 (32.8%) were treated with beta-blockers, respectively. Use of non-selective beta-blockers, but not ß1-selective blockers, was more often associated with non-shockable rhythm than no use of beta-blockers [Denmark: OR 1.93, 95% confidence interval (CI) 1.48-2.52; the Netherlands: OR 2.52, 95% CI 1.15-5.49]. Non-selective beta-blocker use was associated with higher proportion of pulseless electrical activity (PEA) than of shockable rhythm (OR 2.38, 95% CI 1.01-5.65); the association with asystole was of similar magnitude, although not statistically significant compared with shockable rhythm (OR 2.34, 95% CI 0.89-6.18; data on PEA and asystole were only available in the Netherlands). Use of α-ß-dual-receptor blockers was significantly associated with non-shockable rhythm in Denmark (OR 1.21; 95% CI 1.03-1.42) and not significantly in the Netherlands (OR 1.37; 95% CI 0.61-3.07). CONCLUSION: Non-selective beta-blockers, but not ß1-selective beta-blockers, are associated with non-shockable rhythm in OHCA.

Socioeconomic differences in coronary procedures and survival after out-of-hospital cardiac arrest: A nationwide Danish study.

AIM: It remains unclear whether socioeconomic differences exist in post-resuscitation care in out-of-hospital cardiac arrests (OHCA). We aimed to examine socioeconomic differences in coronary procedures and survival after OHCA. METHODS: OHCA patients ≥30 years of cardiac cause with a hospital admission from the Danish Cardiac Arrest Registry, 2001-2014, were divided according to quartiles of household income (lowest, low, high, highest). Associations of income, coronary procedures and 30-day survival were examined by age-standardized incidence rates and incidence rate ratios (IRR), and by logistic regression. RESULTS: A total of 6105 patients were included. Higher-income patients were younger, males and had less comorbidity-burden. Higher-income patients had higher incidence rates for coronary angiographies both day 0-1 and day 2-7 after OHCA (day 0-1: highest: IRR 1.79, 95%CI 1.46-2.21; high: IRR 1.28, 95%CI 1.10-1.51; low: IRR 1.05, 95%CI 0.90-1.23), compared to lowest. Fifty-four percentage of the patients undergoing a coronary angiography received percutaneous-coronary-intervention or coronary-artery-bypass-grafting with no difference among three of the four groups, but lower IRR in low-income patients (IRR 0.74, 95%CI 0.61-0.89) compared to lowest. Higher-income patients had also higher odds for 30-day survival compared to lowest, both in patients with (highest: OR 1.61, 95%CI 1.12-2.32; high: OR 1.13, 95%CI 0.80-1.60; low: OR 1.14, 95%CI 0.81-1.61) and without (highest: OR 2.54, 95%CI 1.83-3.53; high: OR 1.41, 95%CI 1.06-1.87; low: OR 1.12, 95%CI 0.86-1.47) coronary angiography day 0-1. CONCLUSION: Higher-income patients were found associated with more performed coronary angiographies after OHCA, and higher odds for 30-day survival.

[Fatal outcome of coronavirus disease 2019 in a previously healthy 50-year-old man].

In this case report, a 50-year-old man who had no medical history, presented with multiple cardiac arrests following a week with progressing symptoms of pneumonia. After achieving return of spontaneous circulation he presented with respiratory failure with severe hypoxia, septic shock, and multiple organ failure. A chest X-ray showed signs of acute respiratory distress syndrome. Despite aggressive intensive care management, the patient died 7.5 hours after admission. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was later confirmed, and the presumed cause of death was SARS-CoV-2 pneumonia. In conclusion: coronavirus disease 2019 (COVID-19) can lead to a fatal outcome in younger healthy residents, who are not treated timely in case of severe symptoms like dyspnoea.