Serial troponin-I and long-term outcomes in subjects with suspected acute coronary syndrome.

AIMS: It is unclear how serial high-sensitivity troponin-I (hsTnI) concentrations affect long-term prognosis in individuals with suspected acute coronary syndrome (ACS). METHODS AND RESULTS: Subjects who underwent two hsTnI measurements (Siemens TnI Flex® Reagent) separated by 1-7 h, during a first-time hospitalization for myocardial infarction, unstable angina, observation for suspected myocardial infarction, or chest pain from 2012 through 2019, were identified through Danish national registries. Individuals were stratified per their hsTnI concentration pattern (normal, rising, persistently elevated, or falling) and the magnitude of hsTnI concentration change (<20%, >20-50%, or >50% in either direction). We calculated absolute and relative mortality risks standardized to the distributions of risk factors for the entire study population. A total of 20 609 individuals were included of whom 2.3% had died at 30 days, and an additional 4.7% had died at 365 days. The standardized risk of death was highest among persons with a persistently elevated hsTnI concentration (0-30 days: 8.0%, 31-365 days: 11.1%) and lowest among those with two normal hsTnI concentrations (0-30 days: 0.5%, 31-365 days: 2.6%). In neither case did relative hsTnI concentration changes between measurements clearly affect mortality risk. Among persons with a rising hsTnI concentration pattern, 30-day mortality was higher in subjects with a >50% rise compared with those with a less pronounced rise (2.2% vs. <0.1%). CONCLUSION: Among individuals with suspected ACS, those with a persistently elevated hsTnI concentration consistently had the highest risk of death. In subjects with two normal hsTnI concentrations, mortality was very low and not affected by the magnitude of change between measurements.

In this Danish study of >20 000 individuals with suspected heart attack, we confirmed the clinical importance of drawing two consecutive blood samples for measurement of high-sensitivity troponin-I concentrations (a marker of damage to the heart): The risk of death was highest in persons with two elevated high-sensitivity troponin-I concentrations and lowest in those with two normal concentrations.Among persons who had a first normal and a subsequently elevated high-sensitivity troponin-I concentration, a >50% relative rise was associated with significantly higher risk of death at 30 days.

Registered prodromal symptoms of out-of-hospital cardiac arrest among patients calling the medical helpline services.

Background Early identification of warning symptoms among out-of-hospital cardiac arrest (OHCA) patients remains challenging. Thus, we examined the registered prodromal symptoms of patients who called medical helpline services within 30-days before OHCA. Methods Patients unwitnessed by emergency medical services (EMS) aged ≥18 years during their OHCA were identified from the Danish Cardiac Arrest Registry (2014-2018) and linked to phone records from the 24-h emergency helpline (1-1-2) and out-of-hours medical helpline (1813-Medical Helpline) in Copenhagen before the arrest. The registered symptoms were categorized into chest pain; breathing problems; central nervous system (CNS)-related/unconsciousness; abdominal/back/urinary; psychiatric/addiction; infection/fever; trauma/exposure; and unspecified (diverse from the beforementioned categories). Analyses were divided by the time-period of calls (0-7 days/8-30 days preceding OHCA) and call type (1-1-2/1813-Medical Helpline). Results Of all OHCA patients, 18% (974/5442) called helpline services (males 56%, median age 76 years[Q1-Q3:65-84]). Among these, 816 had 1145 calls with registered symptoms. The most common symptom categories (except for unspecified, 33%) were breathing problems (17%), trauma/exposure (17%), CNS/unconsciousness (15%), abdominal/back/urinary (12%), and chest pain (9%). Most patients (61%) called 1813-Medical Helpline, especially for abdominal/back/urinary (17%). Patients calling 1-1-2 had breathing problems (24%) and CNS/unconsciousness (23%). Nearly half of the patients called within 7 days before their OHCA, and CNS/unconsciousness (19%) was the most registered. The unspecified category remained the most common during both time periods (32%;33%) and call type (24%;39%). Conclusions Among patients who called medical helplines services up to 30-days before their OHCA, besides symptoms being highly varied (unspecified (33%)), breathing problems (17%) were the most registered symptom-specific category.

Recurrent syncope in patients with a pacemaker and bradyarrhythmia.

Background. Pacemakers are used to treat syncope in patients with bradyarrhythmia; however, the risk of recurrent syncope has only been investigated in few and smaller studies. Objective. The aim of this study was to investigate the risk of recurrent syncope after pacemaker implantation in patients with bradyarrhythmia and prior syncope. Methods. This retrospective, population-based cohort study included patients with a prior syncope and implantation of a pacemaker using data from the Danish nationwide registers from 1996 to 2017. Cumulative incidence and cox regression was used to estimate the 5-year incidence and the risk of recurrent syncope, respectively. Results. In total, 11,126 patients (median age: 78 years, interquartile range: 69-85, 56% male) were included and the 5-year cumulative incidence of recurrent syncope was 19.6% (95% confidence interval (CI): 18.8-20.3%). Sinus node dysfunction (hazard ratio [HR]: 1.29, 95%CI: 1.17-1.42) and unspecified type of bradyarrhythmia (HR: 1.32, 95%CI: 1.15-1.52) were associated with an increased risk of syncope compared to advanced atrioventricular (AV) block. Male sex (HR: 1.22, 95%CI: 1.22-1.34), cerebrovascular disease (HR: 1.17, 95%CI: 1.05-1.30), and prior number of syncopes were significantly associated with a higher HR of recurrent syncope. Conclusion. Almost one-in-five patients with bradyarrhythmia and prior syncope who had a pacemaker implanted had a recurrent syncope within five years. A higher risk of syncope was observed among patients with sinus node dysfunction and unspecified type of bradyarrhythmia compared to AV block. Male sex, cerebrovascular disease, and prior number of syncopes were associated risk factors of recurrent syncope.

Serial troponin-T and long-term outcomes in suspected acute coronary syndrome.

BACKGROUND: Long-term prognostic implications of serial high-sensitivity troponin concentrations in subjects with suspected acute coronary syndrome are unknown. METHODS AND RESULTS: Individuals with a first diagnosis of myocardial infarction, unstable angina, observation for suspected myocardial infarction, or chest pain from 2012 through 2019 who underwent two high-sensitivity troponin-T (hsTnT) measurements 1-7 h apart were identified through Danish national registries. Absolute and relative risks for death at days 0-30 and 31-365, stratified for whether subjects had normal or elevated hsTnT concentrations, and whether these concentrations changed by <20%, > 20 to 50%, or >50% in either direction from first to second measurement, were calculated through multivariable logistic regression with average treatment effect modeling. Of the 28 902 individuals included, 2.8% had died at 30 days, whereas 4.9% of those who had survived the first 30 days died between days 31-365. The standardized risk of death was highest among subjects with two elevated hsTnT concentrations (0-30 days: 4.3%, 31-365 days: 7.2%). In this group, mortality was significantly higher in those with a > 20 to 50% or >50% rise from first to second measurement, though only at 30 days. The risk of death was very low in subjects with two normal hsTnT concentrations (0-30 days: 0.1%, 31-365 days: 0.9%) and did not depend on relative or absolute changes between measurements. CONCLUSIONS: Individuals with suspected acute coronary syndrome and two consecutively elevated hsTnT concentrations consistently had the highest risk of death. Mortality was very low in subjects with two normal hsTnT concentrations, irrespective of changes between measurements.

Thromboembolism and bleeding in patients with atrial fibrillation and liver disease - A nationwide register-based cohort study: Thromboembolism and bleeding in liver disease.

BACKGROUND: Balancing the risk of thromboembolism and bleeding in patients with liver disease and atrial fibrillation/flutter is particularly challenging. PURPOSE: To examine the risks of thromboembolism and bleeding with use/non-use of oral anticoagulation (including vitamin K-antagonists and direct oral anticoagulants) in patients with liver disease and AF. METHODS: Danish nationwide register-based cohort study of anticoagulant naive individuals with liver disease, incident atrial fibrillation/flutter, and a CHA2DS2-VASc-score≥1 (men) or ≥2 (women), alive 30 days after atrial fibrillation/flutter diagnosis. Thromboembolism was a composite of ischaemic stroke, transient ischaemic attack, or venous thromboembolism. Bleeding was a composite of gastrointestinal, intracerebral, or urogenital bleeding requiring hospitalisation, or epistaxis requiring emergency department visit or hospital admission. Cause-specific Cox-regression was used to estimate absolute risks and average risk ratios standardised to covariate distributions. Because of significant interactions with anticoagulants, results for thromboembolism were stratified for CHA2DS2-VASc-score, and results for bleeding were stratified for cirrhotic/non-cirrhotic liver disease. RESULTS: Four hundred and nine of 1,238 patients with liver disease and new atrial fibrillation/flutter initiated anticoagulants. Amongst patients with a CHA2DS2-VASc-score of 1-2 (2-3 for women), five-year thromboembolism incidence rates were low and similar in the anticoagulant (6.5%) versus no anticoagulant (5.5%) groups (average risk ratio 1.19 [95%CI, 0.22-2.16]). In patients with a CHA2DS2-VASc-score>2 (>3 for women), incidence rates were 16% versus 24% (average risk ratio 0.66 [95%CI, 0.45-0.87]). Bleeding risks appeared higher amongst patients with cirrhotic versus non-cirrhotic disease but were not significantly affected by anticoagulant status. CONCLUSION: Oral anticoagulant initiation in patients with liver disease, incident new atrial fibrillation/flutter, and a high CHA2DS2-VASc-score was associated with a reduced thromboembolism risk. Bleeding risk was not increased with anticoagulation, irrespective of the type of liver disease.

Fascicular heart blocks and risk of adverse cardiovascular outcomes: Results from a large primary care population.

BACKGROUND: Fascicular heart blocks can progress to complete heart blocks, but this risk has not been evaluated in a large general population. OBJECTIVE: The purpose of this study was to investigate the association between various types of fascicular blocks diagnosed by electrocardiographic (ECG) readings and the risk of incident higher degree atrioventricular block (AVB), syncope, pacemaker implantation, and death. METHODS: We studied primary care patients referred for ECG recording between 2001 and 2015. Cox regression models were used to estimate hazard ratios (HRs) as well as absolute risks of cardiovascular outcomes. RESULTS: Of 358,958 primary care patients (median age 54 years; 55% women), 13,636 (3.8%) had any type of fascicular block. Patients were followed up to 15.9 years. We found increasing HRs of incident syncope, pacemaker implantation, and third-degree AVB with increasing complexity of fascicular block. Compared with no block, isolated left anterior fascicular block (LAFB) was associated with 0%-2% increased 10-year risk of developing third-degree AVB (HR 1.6; 95% confidence interval [CI] 1.25-2.05), whereas right bundle branch block combined with LAFB and first-degree AVB was associated with up to 23% increased 10-year risk (HR 11.0; 95% CI 7.7-15.7), depending on age and sex group. Except for left posterior fascicular block (HR 2.09; 95% CI 1.87-2.32), we did not find any relevant associations between fascicular block and death. CONCLUSION: We found that higher degrees of fascicular blocks were associated with increasing risk of syncope, pacemaker implantation, and complete heart block, but the association with death was negligible.

Discontinuation of direct oral anticoagulants among patients with atrial fibrillation according to gender and cohabitation status: a nationwide cohort study.

AIMS: The aim of this study was to evaluate the risk of discontinuing treatment with direct oral anticoagulants (DOACs) among patients with atrial fibrillation (AF) according to cohabitation status and gender. METHODS AND RESULTS: Using the Danish national registers, we identified 32 364 patients with AF aged 40-90 years undergoing treatment with DOACs. The study period was from 2013 to 2017, and patients were followed for 2 years, or until death, outcome, or emigration. The main outcome was discontinuation of DOAC treatment for at least 30 days. The absolute 2-year risk of DOAC discontinuation was highest among men living alone [35.7%, 95% confidence interval (CI): 37.3-34.1%]. Men living alone had a 4.6% (95% CI: 6.4-2.8%) higher absolute risk of discontinuation and a 12% [hazard ratio (HR): 1.12, 95% CI: 1.04-1.20] higher relative risk of discontinuation compared with men living with a partner. Female patients living alone likewise had a higher absolute risk of DOAC discontinuation (2.6%, 95% CI: 4.4-0.09%) compared with female patients living with a partner, yet no statistically significant difference in relative risk. In an analysis evaluating gender, we found male gender to be associated with a significantly higher relative risk of DOAC discontinuation (HR: 1.33, 95% CI: 1.26-1.40) compared with female gender (P-value for interaction with cohabitant status = 0.5996). CONCLUSION: In this nationwide population study, male gender and living alone were associated with a higher risk of DOAC discontinuation among patients with AF.

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.

Insulin resistance genetic risk score and burden of coronary artery disease in patients referred for coronary angiography.

AIMS: Insulin resistance associates with development of metabolic syndrome and risk of cardiovascular disease. The link between insulin resistance and cardiovascular disease is complex and multifactorial. Confirming the genetic link between insulin resistance, type 2 diabetes, and coronary artery disease, as well as the extent of coronary artery disease, is important and may provide better risk stratification for patients at risk. We investigated whether a genetic risk score of 53 single nucleotide polymorphisms known to be associated with insulin resistance phenotypes was associated with diabetes and burden of coronary artery disease. METHODS AND RESULTS: We genotyped patients with a coronary angiography performed in the capital region of Denmark from 2010-2014 and constructed a genetic risk score of the 53 single nucleotide polymorphisms. Logistic regression using quartiles of the genetic risk score was performed to determine associations with diabetes and coronary artery disease. Associations with the extent of coronary artery disease, defined as one-, two- or three-vessel coronary artery disease, was determined by multinomial logistic regression. We identified 4,963 patients, of which 17% had diabetes and 55% had significant coronary artery disease. Of the latter, 27%, 14% and 14% had one, two or three-vessel coronary artery disease, respectively. No significant increased risk of diabetes was identified comparing the highest genetic risk score quartile with the lowest. An increased risk of coronary artery disease was found for patients with the highest genetic risk score quartile in both unadjusted and adjusted analyses, OR 1.21 (95% CI: 1.03, 1.42, p = 0.02) and 1.25 (95% CI 1.06, 1.48, p<0.01), respectively. In the adjusted multinomial logistic regression, patients in the highest genetic risk score quartile were more likely to develop three-vessel coronary artery disease compared with patients in the lowest genetic risk score quartile, OR 1.41 (95% CI: 1.10, 1.82, p<0.01). CONCLUSIONS: Among patients referred for coronary angiography, only a strong genetic predisposition to insulin resistance was associated with risk of coronary artery disease and with a greater disease burden.

Impact of plasma potassium normalization on short-term mortality in patients with hypertension and hypokalemia or low normal potassium.

BACKGROUND: Hypokalemia is common in patients treated with antihypertensive drugs, but the impact of correcting hypokalemia is insufficiently studied. We examined the consequences of hypokalemia and borderline hypokalemia correction in patients with hypertension. METHODS: We identified 8976 patients with hypertension and plasma potassium concentrations ≤3.7 mmol/L within 100 days from combination antihypertensive therapy initiation. The first measurement between 6 and 100 days after the episode with potassium ≤3.7 mmol/L was retained. We investigated all-cause and cardiovascular mortality within 60-days from the second potassium measurement using Cox regression. Mortality was examined for seven predefined potassium intervals derived from the second measurement: 1.5-2.9 mmol/L (n = 271), 3.0-3.4 mmol/L (n = 1341), 3.5-3.7 (n = 1982) mmol/L, 3.8-4.0 mmol/L (n = 2398, reference), 4.1-4.6 mmol/L (n = 2498), 4.7-5.0 mmol/L (n = 352) and 5.1-7.1 mmol/L (n = 134). RESULTS: Multivariable analysis showed that potassium concentrations 1.5-2.9 mmol/L, 3.0-3.4 mmol/L, 4.7-5.0 mmol/L and 5.1-7.1 mmol/L were associated with increased all-cause mortality (HR 2.39, 95% CI 1.66-3.43; HR 1.36, 95% CI 1.04-1.78; HR 2.36, 95% CI 1.68-3.30 and HR 2.62, 95% CI 1.73-3.98, respectively). Potassium levels <3.0 and > 4.6 mmol/L were associated with increased cardiovascular mortality. The adjusted standardized 60-day mortality risks in the seven strata were: 11.7% (95% CI 8.3-15.0%), 7.1% (95% CI 5.8-8.5%), 6.4% (95% CI 5.3-7.5%), 5.4% (4.5-6.3%), 6.3% (5.4-7.2%), 11.6% (95% CI 8.7-14.6%) and 12.6% (95% CI 8.2-16.9%), respectively. CONCLUSIONS: Persistent hypokalemia was frequent and associated with increased all-cause and cardiovascular mortality. Increase in potassium to levels > 4.6 mmol/L in patients with initial hypokalemia or low normal potassium was associated with increased all-cause and cardiovascular mortality.

Risk of Myocardial Infarction in Anticoagulated Patients With Atrial Fibrillation.

BACKGROUND: Evidence is conflicting as to the efficacy of direct oral anticoagulation (DOAC) and vitamin K antagonist (VKA) for prevention of myocardial infarction (MI). OBJECTIVES: This study aimed to investigate the risk of MI associated with the use of apixaban, dabigatran, rivaroxaban, and VKA in patients with atrial fibrillation. METHODS: Patients with atrial fibrillation were identified using Danish health care registers and stratified by initial oral anticoagulant treatment. Standardized absolute 1-year risks were estimated based on Cox regression for hazard rates of MI hospitalizations and mortality. Reported were absolute risks separately for the oral anticoagulation treatments and standardized to the characteristics of the study population. RESULTS: Of the 31,739 patients included (median age, 74 years; 47% females), the standardized 1-year risk of MI for VKA was 1.6% (95% confidence interval [CI]: 1.3 to 1.8), apixaban was 1.2% (95% CI: 0.9 to 1.4), dabigatran was 1.2% (95% CI: 1.0 to 1.5), and rivaroxaban was 1.1% (95% CI: 0.8 to 1.3). No significant risk differences were observed in the standardized 1-year risks of MI among the DOACs: dabigatran versus apixaban (0.04%; 95% CI: -0.3 to 0.4), rivaroxaban versus apixaban (0.1%; 95% CI: -0.4 to 0.3), and rivaroxaban versus dabigatran (-0.1%; 95% CI: -0.5 to 0.2). The risk differences for DOACs versus VKA were all significant: -0.4% (95% CI: -0.7 to -0.1) for apixaban, -0.4% (95% CI: -0.7 to -0.03) for dabigatran, and -0.5% (95% CI: -0.8 to -0.2) for rivaroxaban. CONCLUSIONS: No significant risk differences of MI were found in the direct comparisons of DOACs, and DOACs were all associated with a significant risk reduction of MI compared with VKA.

Risk of Ischemic Stroke, Hemorrhagic Stroke, Bleeding, and Death in Patients Switching from Vitamin K Antagonist to Dabigatran after an Ablation.

BACKGROUND: Safety regarding switching from vitamin K antagonist (VKA) to dabigatran therapy in post-ablation patients has never been investigated and safety data for this is urgently needed. The objective of this study was to examine if switch from VKA to dabigatran increased the risk of stroke, bleeding, and death in patients after ablation for atrial fibrillation. METHODS: Through the Danish nationwide registries, patients with non-valvular atrial fibrillation undergoing ablation were identified, in the period between August 22nd 2011 and December 31st 2015. The risk of ischemic stroke, hemorrhagic stroke, bleeding, and death, related to switching from VKA to dabigatran was examined using a multivariable Poisson regression model, where Incidence rate ratios (IRR) were estimated using VKA as reference. RESULTS: In total, 4,236 patients were included in the study cohort. The minority (n = 470, 11%) switched to dabigatran in the follow up period leaving the majority (n = 3,766, 89%) in VKA treatment. The patients in the dabigatran group were older, were more often males, and had higher CHA2DS2-VASc, and HAS-BLED scores. The incident rates of bleeding and death were almost twice as high in the dabigatran group compared with the VKA group. When adjusting for the individual components included in the CHA2DS2-VASc and HAS-BLED scores, the multivariable Poisson analyses yielded a non-significant IRR (95%CI) of 1.64 (0.72-3.75) for bleeding and of 1.41 (0.66-3.00) for death associated with the dabigatran group, compared to the VKA group. A significant increased risk of bleeding was found in the 110mg bid group with an IRR (95%CI) of 4.49(1.40-14.5). CONCLUSION: Shifting from VKA to dabigatran after ablation was associated with twice as high incidence of bleeding compared to the incidence in patients staying in VKA treatment. The only significant increased risk found in the adjusted analyses was for bleeding with 110mg bid dabigatran and not for 150mg bid. Since there was no dose-response for bleeding, the switch from VKA to dabigatran in itself was not a risk factor for bleeding.