Exploring cardiac effects after oxytocin 2.5 IU or carbetocin 100 µg: A randomised controlled trial in women undergoing planned caesarean delivery.

BACKGROUND: Oxytocin can stimulate release of myocardial biomarkers troponin I and T, prolong QTc and induce ST-depression. OBJECTIVE: To explore cardiac changes after either intravenous carbetocin or oxytocin. STUDY DESIGN: Exploratory phase 4 randomised controlled trial. SETTING: Obstetrics units of Oslo University Hospital, Norway between September 2015 and May 2018. PARTICIPANTS: Forty healthy, singleton pregnant women aged 18 to 50 years at gestational age at least 36 weeks with a planned caesarean delivery. INTERVENTIONS: Participants were randomised to receive either oxytocin 2.5 IU or carbetocin 100 µg immediately after delivery. MAIN OUTCOME MEASURES: The primary endpoint was the assessment of troponin I within 48 h of study drug administration. Troponin I and T, and creatine kinase myocardial band assessments were measured before spinal anaesthesia (baseline), and again at 4, 10 and 24 h after delivery. QTc, ST-depression and relative increase in heart rate were recorded from start of study drug administration to 10 min after delivery. All adverse events were monitored. RESULTS: Compared with the carbetocin group, higher troponin I levels were observed in the oxytocin group at 4 h and 10 h after delivery. For both treatment groups, an increase from baseline in troponin I and T was most pronounced at 10 h after delivery, and it had begun to decline by 24 h. QTc increased with time after administration of both study drugs, with a mean maximum increase of 10.4 ms observed at 9 min (P   <  0.001). No statistical differences were observed in QTc ( P  = 0.13) or ST-depression ( P  = 0.11) between the treatment groups. CONCLUSIONS: Oxytocin 2.5 IU and carbetocin 100 µg caused a similar increase in QTc. The trial was underpowered with regards to ST-depression and the release of myocardial biomarkers and these warrant further investigation. Data from this trial will inform a larger phase 4 trial to determine potential drug differences in troponin release. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02528136.

Diagnostic Thresholds for Pre-Diabetes Mellitus and Diabetes Mellitus and Subclinical Cardiac Disease in the General Population: Data From the ACE 1950 Study.

Background Diabetes mellitus (DM) is associated with left ventricular remodeling and incident heart failure, but the association between glycated hemoglobin A1c (HbA1c) and subclinical cardiac disease is not established. We aimed to determine the associations between HbA1c and (1) echocardiographic measures of left ventricular structure and function, and (2) cardiovascular biomarkers: cardiac troponin T, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and CRP (C-reactive protein). Methods and Results Participants (n=3688) born in 1950 from the population-based ACE (Akershus Cardiac Examination) 1950 Study were classified as DM (HbA1c≥6.5% or self-reported DM), pre-DM (HbA1c 5.7%-6.5%), and no-DM (HbA1c<5.7%). DM, pre-DM, and no-DM were classified in 380 (10%), 1630 (44%), and 1678 (46%) participants, respectively. Mean age was 63.9±0.7 years, mean body mass index was 27.2±4.4 kg/m2, and 49% were women. Higher HbA1c was associated with worse left ventricular systolic (ejection fraction and global longitudinal strain) and diastolic (E/e'-ratio) function, myocardial injury (cardiac troponin T), inflammation (CRP), and impaired neurohormonal homeostasis (NT-proBNP) (P<0.001 in unadjusted and P<0.01 in adjusted analysis for all). The associations between HbA1c and cardiovascular biomarkers were independent of the echocardiographic variables, and vice versa. Associations were nonlinear (P<0.05 for nonlinearity) and appeared stronger in the pre-DM range of HbA1c than the no-DM and DM range. Conclusions HbA1c was associated with indexes of subclinical cardiovascular disease, and this was more pronounced in pre-DM. Our results suggest that cardiovascular preventive measures should be considered also in subjects with hyperglycemia and HbA1c below the established DM cutoff. Registration clinicaltrials.gov. Identifier: NCT01555411.

High-sensitivity troponin I in persistent atrial fibrillation - relation to NT-proBNP and markers of inflammation and haemostasis.

PURPOSE: As cardiac troponins emerge as prognostic markers in atrial fibrillation (AF), it is important to identify mechanisms initiating and perpetuating cardiac troponin release, including its relations to other circulating biomarkers, in AF populations. We studied associations between high-sensitivity troponin I (hs-TnI) and markers representing myocardial wall tension, inflammation and haemostasis in persistent AF. METHODS: In a double blind, placebo-controlled study, 171 patients referred for electrical cardioversion for persistent AF were randomised to receive candesartan or placebo for 3-6 weeks before and 6 months after cardioversion. Associations between baseline levels of hs-TnI and other biomarkers were investigated by bivariate non-parametric correlations (Spearman's correlation coefficient denoted rs). RESULTS: Baseline levels of hs-TnI correlated significantly, although weakly, with interleukin-6 (rs = 0.260, p = .003), N-terminal pro-B-type natriuretic peptide (rs = 0.251, p = .004), tissue-plasminogen activator antigen (rs = 0.233, p = .008), D-dimer (rs = 0.220, p = .013), E-selectin (rs = 0.207, p = .019), high-sensitivity C-reactive protein (rs = 0.202, p = .022) and vascular cell adhesion molecule-1 (rs = 0.189, p = .032). CONCLUSIONS: Hs-TnI correlated weakly with biomarkers representing myocardial wall tension, inflammation and haemostasis in persistent AF. The lack of any strong correlation between hs-TnI and the investigated biomarkers is in concert with the idea that hs-TnI release is an independent process parallel to other pathophysiological mechanisms associated with AF.

Neurohormonal Blockade and Circulating Cardiovascular Biomarkers During Anthracycline Therapy in Breast Cancer Patients: Results From the PRADA (Prevention of Cardiac Dysfunction During Adjuvant Breast Cancer Therapy) Study.

BACKGROUND: Anthracyclines are associated with cardiotoxic effects. Cardiovascular biomarkers may reflect myocardial injury, dysfunction, inflammation, and fibrosis and may precede and predict the development of left ventricular impairment. The aim of this study was to assess: (1) longitudinal change in circulating cardiovascular biomarkers, (2) the effect of metoprolol succinate and candesartan cilexetil on the biomarker response, and (3) the associations between on-treatment changes in biomarker concentrations and subsequent left ventricular dysfunction in patients with early breast cancer receiving anthracyclines. METHODS AND RESULTS: This report encompasses 121 women included in the 2×2 factorial, placebo-controlled, double-blind PRADA (Prevention of Cardiac Dysfunction During Adjuvant Breast Cancer Therapy) trial with metoprolol and candesartan given concomitantly with anticancer therapy containing the anthracycline, epirubicin (total cumulative dose, 240-400 mg/m2). Cardiovascular magnetic resonance, echocardiography images, and circulating levels of biomarkers were obtained before and after anthracycline treatment. Cardiac troponins I and T, B-type natriuretic peptide, N-terminal pro-B-type natriuretic peptide, C-reactive protein, and galectin-3 increased during anthracycline therapy (all P<0.05). The troponin response was attenuated by metoprolol (P<0.05), but not candesartan. There was no association between change in biomarker concentrations and change in cardiac function during anthracycline therapy. CONCLUSIONS: Treatment with contemporary anthracycline doses for early breast cancer is associated with increase in circulating cardiovascular biomarkers. This increase is, however, not associated with early decline in ventricular function. Beta-blockade may attenuate early myocardial injury, but whether this attenuation translates into reduced risk of developing ventricular dysfunction in the long term remains unclear. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrial.gov. Unique identifier: NCT01434134.

Vitamin D Status and Long-Term Mortality in Community-Acquired Pneumonia: Secondary Data Analysis from a Prospective Cohort.

BACKGROUND: Low vitamin D status has been associated with short-term (30-day) mortality in hospitalized adults with community-acquired pneumonia (CAP). Data on its prevalence in these patients are scarce, and impact on long-term prognosis is unknown. We examined the prevalence of vitamin D deficiency and inadequacy and their effect on long-term mortality in hospitalized adults with CAP. METHODS: Secondary follow-up analysis of data from a prospectively recruited (January 2008-January 2011) well-defined cohort of 241 hospital survivors of CAP (Norway, latitude 60°N). Serum 25-hydroxyvitamin D levels, demographic, clinical, and laboratory data were measured within 48 hours of admission. The etiology of CAP was established in 63% of patients through extensive microbiological investigations. Mortality data were obtained from the national Cause of Death Registry. Explanatory strategy and Cox regression models were used to explore the association between vitamin D status and all-cause mortality. RESULTS: Median age was 66 years. Eighty-seven (36%) patients were vitamin D deficient (<30 nmol/L), 81 (34%) were inadequate (30-49 nmol/L), and 73 (30%) were sufficient (≥50 nmol/L). Seventy-two patients died over a median of 1839 days (range 1-2520 days), corresponding to cumulative 5-year survival rates of 66.2% (95% CI 56.2-76.2%), 77.0% (67.6-86.4%), and 77.8% (67.8-87.8%) for vitamin D deficient, inadequate, and sufficient patients, respectively. After adjusting for confounders (age, chronic obstructive pulmonary disease, immunocompromization and season), vitamin D deficiency, but not inadequacy, was significantly associated with higher mortality compared to patients with sufficiency (HR 1.91, 95% CI 1.06-3.45; P = .031). CONCLUSIONS: There is a high prevalence of vitamin D deficiency and inadequacy among hospitalized adults with CAP. The results of this study also suggest that vitamin D deficiency is associated with an increased risk of mortality way beyond the short-term in these patients.

Troponin I levels in permanent atrial fibrillation-impact of rate control and exercise testing.

BACKGROUND: High-sensitivity troponin I (hs-TnI) and troponin T (hs-TnT) are moderately correlated and independently related to outcome in atrial fibrillation (AF). Rate controlling therapy has been shown to reduce hs-TnT, however the potential impact on hs-TnI levels, and whether this differs from the effects on hs-TnT, has not been investigated previously. METHODS: Sixty patients with stable, permanent AF without heart failure or known ischemic heart disease were included in a randomised crossover study (mean age 71 ± 9 years, 18 women). Diltiazem 360 mg, verapamil 240 mg, metoprolol 100 mg, and carvedilol 25 mg were administered once daily for three weeks, in a randomised sequence. At baseline and on the last day of each treatment period, hs-TnI was measured at rest and after a maximal exercise test and compared to hs-TnT. RESULTS: Hs-TnI and hs-TnT correlated moderately at baseline (rs = 0.582, p < 0.001). All drugs reduced both the resting and the peak exercise levels of hs-TnI compared with baseline (p < 0.001 for all). The decline in resting hs-TnI and hs-TnT values relative to baseline levels was similar for all drugs except for verapamil, which reduced hs-TnI more than hs-TnT (p = 0.017). Levels of hs-TnI increased significantly in response to exercise testing at baseline and at all treatment regimens (p < 0.001 for all). The relative exercise-induced increase in hs-TnI was significantly larger compared to hs-TnT at baseline (p < 0.001), on diltiazem (p < 0.001) and on verapamil (p = 0.001). CONCLUSIONS: In our population of stable, permanent AF patients, all four rate control drug regimens reduced hs-TnI significantly, both at rest and during exercise. The decline in hs-TnI and hs-TnT levels associated with beta-blocker and calcium channel blocker treatment was similar, except for a larger relative decrease in hs-TnI levels following verapamil treatment. TRIAL REGISTRATION: www.clinicaltrials.gov ( NCT00313157 ).

Effect of weight loss on subclinical myocardial injury: A clinical trial comparing gastric bypass surgery and intensive lifestyle intervention.

AIMS: To investigate the effect of weight loss induced by bariatric surgery and intensive lifestyle intervention on levels of circulating high-sensitivity cardiac troponin I. METHODS AND RESULTS: We measured high-sensitivity cardiac troponin I concentrations pre- and 12 months post-intervention in 136 subjects with morbid obesity participating in a controlled clinical trial comparing the effect of intensive lifestyle intervention vs. Roux-en-Y gastric bypass. At baseline median (interquartile range) high-sensitivity cardiac troponin I levels were 2.40 (1.28-3.95) ng/L in the bariatric surgery group and 2.35 (1.38-4.40) ng/L in the intensive lifestyle intervention group (p = 0.736). The high-sensitivity cardiac troponin I concentration in a normal-weight control group was 0.90 (0.60-2.13) ng/L. During 12 months of follow-up, high-sensitivity cardiac troponin I decreased significantly more in the bariatric surgery group than in the intensive lifestyle intervention group (0.80 (0-1.80) vs. 0.15 (-0.50 to 1.00) ng/L; p = 0.002). In a multivariate logistic regression model, surgery emerged as a predictor of reduction in high-sensitivity cardiac troponin I levels (odds ratio 2.32; 95% confidence intervals 1.03-5.22; p = 0.041) independent of age, gender and other possible confounding baseline variables. In subsequent multivariate analyses, reductions in body weight and triglycerides emerged as possible mediators of reduction in circulating levels of high-sensitivity cardiac troponin I. CONCLUSION: In patients with morbid obesity, bariatric surgery was associated with a significantly greater reduction in high-sensitivity cardiac troponin I, an index of subclinical myocardial injury, than intensive lifestyle intervention. The reduction appeared to be mediated by reductions in body weight and serum triglycerides. This suggests that weight loss following bariatric surgery may reduce cardiometabolic stress and subsequent risk of heart failure.

High-Sensitivity Troponin I and Rhythm Outcome after Electrical Cardioversion for Persistent Atrial Fibrillation.

OBJECTIVES: We hypothesised that high-sensitivity troponin I (hs-TnI) might predict long-term rhythm outcome after cardioversion for persistent atrial fibrillation (AF), and that maintenance of sinus rhythm and/or treatment with the angiotensin II type 1 receptor blocker candesartan would reduce hs-TnI levels. METHODS: In a double-blind, placebo-controlled study, 171 patients referred for electrical cardioversion for AF were randomised to receive candesartan or placebo for 3-6 weeks before cardioversion and for 6 months after electrical cardioversion. Blood samples for analysis of hs-TnI (Abbott Diagnostics) were available in 129 patients at baseline and in 60 successfully cardioverted patients at study end. RESULTS: Hs-TnI was detectable in all subjects, with a median value of 5.3 ng/l (25th percentile 3.7, 75th percentile 7.2). hs-TnI at baseline was not predictive of rhythm outcome 6 months after electrical cardioversion for persistent AF. Treatment with candesartan did not influence the levels of hs-TnI. hs-TnI was unchanged from baseline to study end in patients who maintained sinus rhythm [4.9 (3.7, 7.0) and 5.0 (4.0, 6.4) ng/l, respectively; p = 0.699). CONCLUSIONS: hs-TnI did not predict AF recurrence after cardioversion. hs-TnI levels were unchanged in patients maintaining sinus rhythm for 6 months after electrical cardioversion. hs-TnI levels were not influenced by treatment with candesartan.

Impact of atrial fibrillation on levels of high-sensitivity troponin I in a 75-year-old population.

PURPOSE: Atrial fibrillation (AF) has been associated with elevated levels of cardiac troponins; however, it is not clear if this association is independent of underlying cardiovascular disease. The aim of this study was to investigate the impact of AF on cardiac troponin I levels in a 75-year-old cohort from the general population, using a recently introduced, highly sensitive assay. METHODS: All 75-year-old citizens in Asker and Baerum counties were invited to participate in a prevalence study of AF. High-sensitive troponin I (hs-TnI) levels were measured (Abbott Diagnostics) in serum samples collected from 62 subjects with AF and a gender-matched control group of 126 subjects in sinus rhythm. RESULTS: Hs-TnI was detectable in all subjects (median 7.3 ng/L [range 3.0-88.7]). Patients with AF had higher levels than subjects in sinus rhythm (8.3 ng/L [3.7-88.7] vs. 6.8 ng/L [3.0-77.5]; p = 0.011). Male gender (p = 0.002), hypertension (p = 0.001), coronary heart disease (p < 0.001), heart failure (p < 0.001), prior stroke or transient ischemic attack (p = 0.013) and serum creatinine (p < 0.001) were all associated with higher levels of hs-TnI in univariate analysis. Heart failure and coronary heart disease remained significantly associated with hs-TnI in multivariate analysis, whereas the relation between AF and hs-TnI was no longer statistically significant. CONCLUSION: All subjects had detectable levels of hs-TnI. AF patients had higher hs-TnI levels than subjects in sinus rhythm; however, this difference was not statistically significant after adjustment for heart failure and coronary heart disease.

Improved rate control reduces cardiac troponin T levels in permanent atrial fibrillation.

BACKGROUND: Detectable levels of troponins are often found in serum of patients with atrial fibrillation (AF), and recent reports suggest that Tn concentrations are independently related to patient prognosis. HYPOTHESIS: We hypothesized that treatment with common rate-reducing drugs might lower the levels of cardiac troponin T (TnT) in patients with permanent AF. We also wanted to investigate whether the different drugs would impact the Tn levels differently. METHODS: Sixty patients were included (mean age 71 ± 9 years, 18 women) in this randomized crossover study. All patients had stable, permanent AF without ischemic heart disease or congestive heart failure. Diltiazem 360 mg, verapamil 240 mg, metoprolol 100 mg, and carvedilol 25 mg were administered once daily for 3 weeks, in a randomized sequence. At baseline and on the last day of each treatment period, TnT concentrations were measured at rest and after a maximal exercise test. RESULTS: TnT was detectable in all patients. In 22% of the patients, TnT concentrations were above the threshold normally used for diagnosing myocardial infarction. All drugs reduced the levels of TnT significantly compared with baseline (P < 0.001 for all), but there were no significant differences between the treatments. Levels of TnT increased significantly in response to exercise testing (P < 0.001 for all). CONCLUSIONS: Elevated TnT was demonstrated in a large proportion of stable patients with permanent AF without ischemic heart disease. A moderate reduction of heart rate by the study drugs was associated with a significant reduction in levels of TnT.