Pulmonary Valve Replacement in Tetralogy of Fallot: Procedural Volume and Durability of Bioprosthetic Pulmonary Valves

BACKGROUND

Robust data on changes in pulmonary valve replacement (PVR) procedural volume and predictors of bioprosthetic pulmonary valve (BPV) durability in patients with tetralogy of Fallot (TOF) are scarce.

OBJECTIVES

This study sought to assess temporal trends in PVR procedural volume and BPV durability in a nationwide, retrospective TOF cohort.

METHODS

Data were obtained from patient records. Robust linear regression was used to assess temporal trends in PVR procedural volume. Piecewise exponential additive mixed models were used to estimate BPV durability, defined as the time from implantation to redo PVR with death as a competing risk, and to assess risk factors for reduced durability.

RESULTS

In total, 546 PVR were performed in 384 patients from 1976 to 2021. The annual number of PVR increased from 0.4 to 6.0 per million population (P < 0.001). In the last decade, the transcatheter PVR volume increased by 20% annually (P < 0.001), whereas the surgical PVR volume did not change significantly. The median BPV durability was 17 years (Q1: 10-Q3: 10 years-not applicable). There was no significant difference in the durability of different BPV after adjustment for confounders. Age at PVR (HR: 0.78 per 10 years from <1 year; 95% CI: 0.63-0.96; P = 0.02) and true inner valve diameter (9-17 mm vs 18-22 mm HR: 0.40; 95% CI: 0.22-0.73; P = 0.003 and 18-22 mm vs 23-30 mm HR: 0.59; 95% CI: 0.25-1.39; P = 0.23) were associated with reduced BPV durability in multivariate models.

CONCLUSIONS

The PVR procedural volume has increased over time, with a greater increment in transcatheter than surgical PVR during the last decade. Younger patient age at PVR and a smaller true inner valve diameter predicted reduced BPV durability.

Postoperative free water administration is associated with dysnatremia after congenital heart disease surgery in infants

Dysnatremia after congenital heart disease (CHD) surgery is common. European guidelines on intraoperative fluid therapy in children recommend isotonic solutions to avoid hyponatremia, but prolonged cardiopulmonary bypass and administration of high sodium-containing solutions (i.e., blood products and sodium bicarbonate) are associated with postoperative hypernatremia. The aim of the study was to describe fluid composition prior to and during the development of postoperative dysnatremia. A retrospective observational, single-center study including infants undergoing CHD surgery. Demographics and clinical characteristics were registered. Highest and lowest plasma sodium values were recorded and associations with perioperative fluid administration, blood products, crystalloids, and colloids were explored in relation to three perioperative periods. Postoperative dysnatremia occurred in nearly 50% of infants within 48 h after surgery. Hypernatremia was mainly associated with administration of blood products (median [IQR]: 50.5 [28.4-95.5] vs. 34.5 [18.5-61.1] mL/kg; p = 0.001), and lower free water load (1.6 [1.1-2.2] mL/kg/h; p = 0.01). Hyponatremia was associated with a higher free water load (2.3 [1.7-3.3] vs. 1.8 [1.4-2.5] mL/kg/h; p = 0.001) and positive fluid balance. On postoperative day 1, hyponatremia was associated with higher volumes of free water (2.0 [1.5-2.8] vs. 1.3 [1.1-1.8] mL/kg/h; p < 0.001) and human albumin, despite a larger diuresis and more negative daily fluid balance. Postoperative hyponatremia occurred in 30% of infants despite restrictive volumes of hypotonic maintenance fluid, whereas hypernatremia was mainly associated with blood product transfusion. Individualized fluid therapy, with continuous reassessment to reduce the occurrence of postoperative dysnatremia is mandatory in pediatric cardiac surgery. Prospective studies to evaluate fluid therapy in pediatric cardiac surgery patients are warranted.

Temporal changes in the surgical management of patients with tetralogy of Fallot in Denmark: a nationwide cohort study

OBJECTIVES

To assess temporal changes in the surgical management of patients with tetralogy of Fallot including the timing of interventions, surgical techniques, reinterventions and survival in a nationwide cohort.

METHODS

Patients with tetralogy of Fallot in Denmark were divided into 3 eras based on their year of birth: early (1977-1991), intermediate (1992-2006) and late (2007-2021).

RESULTS

The cohort consisted of 745 patients. Median follow-up was 21.2 years (13.7-30.5). There was a temporal trend towards less shunt palliation (-0.3% per year, 95% CI -0.05 to -0.1). Median age at intracardiac repair was 2.9 years (1.8-5.0), 0.8 years (0.5-1.3) and 0.5 years (0.4-0.7) (P < 0.001) in the early, intermediate and late era, respectively. There was a temporal trend towards less valve-sparing repair (-0.7% per year, 95% CI -0.5 to -1.0) and more repair with transannular patches (0.7% per year, 95% CI 0.5-1.0). Survival at 10 years was 79% (64-76), 90% (87-93) and 95% (92-98) (P < 0.001) and pulmonary valve replacement within the first 10 years after intracardiac repair was performed in 3% (1-6), 12% (8-16) and 21% (13-29) (P < 0.001) in the early, intermediate and late era, respectively.

CONCLUSIONS

There was a temporal trend towards less shunt palliation and intracardiac repair at a younger age with more use of transannular patches. While survival throughout childhood and adolescence has improved, more patients undergo pulmonary valve replacement during the first 10 years after intracardiac repair.

Clinical assessment of blood pressure in 60 girls with Turner syndrome compared to 1888 healthy Danish girls

OBJECTIVE

Hypertension contributes to increased risk of cardiovascular disease in patients with Turner syndrome (TS). Our objective was to evaluate blood pressure (BP) in girls with TS followed longitudinally through childhood and adolescence compared to a newly established BP reference material.

DESIGN

Cohort study with data collected from 1991 to 2019 consisting of a population-based reference cohort and a group of girls with TS followed at a single tertiary centre.

PATIENTS/PARTICIPANTS

Reference population of 1888 healthy girls with 4890 BP recordings and 60 girls with TS with 365 BP recordings.

MEASUREMENTS

Difference in diastolic BP (DBP) and systolic BP (SBP), expressed in standard deviation scores (SDS), between girls with TS and the reference population, unadjusted and adjusted for BMI. Difference in BP (SDS) between TS subgroups (karyotype, oestrogen treatment, cardiac diagnosis).

RESULTS

The girls with TS had significantly higher DBP (mean ± SD, 0.72 SDS ± 0.95; p < .001) and SBP (0.53 SDS ± 1.11; p = .001) than the reference population. Adjusted for BMI, girls with TS had significantly higher DBP (mean ± SE, 0.71 SDS ± 0.12; p < .001) but not SBP (0.17 SDS ± 0.16; p = .29). There was no significant difference in DBP (median, IQR: 0.97 SDS, 0.30-1.58 vs. 0.76 SDS, 0.10-1.20; p = .31) or SBP (0.51 SDS, 0.15-1.30 vs. 0.57 SDS, -0.30 to 1.05; p = .67) between individuals with or without a cardiac diagnosis. In the TS population, 55% (31/56) had at least one BP recording above the hypertension threshold.

CONCLUSIONS

Our findings indicate that standardised longitudinal routine monitoring of BP in girls with TS already in childhood is of utmost importance.

Postoperative dysnatremia in infants after open-heart surgery occurs frequently and is associated with prolonged intensive care length of stay

BACKGROUND

Dysnatremia after surgery for congenital heart disease (CHD) is well known and has been associated with prolonged pediatric intensive care unit length of stay (PICU-LOS). Fluctuations in plasma sodium levels occur perioperatively. The primary aim of the study was to evaluate the occurrence of dysnatremia during the first 48 h after surgery and whether it was associated with PICU-LOS. The secondary aim was to evaluate if the degree of sodium fluctuations was associated with PICU-LOS.

METHODS

A retrospective observational, single-center study including infants undergoing surgery for CHD. The highest and lowest plasma sodium value was registered for the prespecified time periods. PICU-LOS was analyzed in relation to the occurrence of dysnatremia and the degree of plasma sodium fluctuations. The occurrence of dysnatremia was evaluated in relation to surgical procedure and fluid administration.

RESULTS

Two hundred and thirty infants who underwent 249 surgical procedures were included. Dysnatremia developed in more than 60% within 48 h after surgery. Infants with normonatremia had a 40%-50% shorter PICU-LOS among children in RACHS-1 category 3-6, compared with infants developing either hypo- or hyper-/hyponatremia within 48 h after surgery (p = .006). Infants who had a decline of plasma sodium >11 mmol/L had almost double the PICU-LOS compared to those with a decline of <8 mmol/L.

CONCLUSION

Dysnatremias were common after surgery for CHD and associated with prolonged PICU-LOS. The degree of decline in plasma sodium was significantly associated with PICU-LOS. Fluid administration both in terms of volume and components (blood products and crystalloids) as well as diuresis were related to the occurrence of dysnatremias.

Heart disease among Greenlandic children and young adults: a nationwide cohort study

BACKGROUND

The incidences of heart disease (HD) and congenital heart disease (CHD) among Inuit in Greenland (GL) and Denmark (DK) are unknown. This study aims to estimate incidence rates (IRs) of HD and CHD among the young Inuit populations in Greenland and Denmark compared with rates among young non-Inuit populations in the same countries.

METHODS

A register-based nationwide cohort including all individuals living in Greenland and Denmark from birth to age <40 years through 1989-2014 was formed. Ethnicity was considered Inuit/mixed if at least one parent was registered as being born in Greenland. Information on HD and CHD hospitalization was obtained from national inpatient registers using ICD-8 and ICD-10 codes.

RESULTS

HD IR was lower among individuals living in Greenland compared with those living in Denmark, [73.35GL (95% confidence interval (CI) 68.07 to 79.03)] vs [88.07DK (95% CI 87.38 to 88.76)], whereas CHD IRs were almost similar in the two countries [IR 34.44GL (95% CI 30.89 to 38.40) vs IR 34.67DK (95% CI 34.24 to 35.10)]. Being of Inuit/mixed ethnicity was associated with an increased risk of both HD and CHD compared with non-Inuit in Greenland and Denmark [adjusted hazard ratio HD 2.07GL (95% CI 1.25 to 3.42)] and CHD [2.92GL (95% CI 1.34 to 6.38)].

CONCLUSION

HD IR was lower in individuals living in Greenland compared with individuals living in Denmark, whereas the CHD IRs were almost the same for both countries. However, the risk of HD including CHD was higher among individuals of Inuit/mixed ethnicity compared with non-Inuit in both countries, suggesting a role of ethnicity among children and younger adults.

Cohort profile: the vitamin A and D and nitric oxide (AD-ON) observational cohort on lung development and symptoms in premature and mature children in North Zealand, Denmark

PURPOSE

The risk of developing asthma-like symptoms and asthma in childhood is influenced by genetics, environmental exposures, prenatal and early postnatal events, and their interactions. The cohort name refers to vitamins A and D, and nitric oxide (NO) spelt backwards and this cohort profile paper aims to present the data collection and aim of the cohort.The overall aim when establishing this cohort was to investigate if childhood lung function can be traced back to early neonatal lung function and fractional exhaled NO (FeNO) and investigate prenatal and postnatal risk factors including maternal and neonatal vitamin A and D levels in preterm and term born children.

PARTICIPANTS

One thousand five hundred women and their babies born at Nordsjaellands Hospital in Denmark from 2013 to 2014 were included in the AD-ON research biobank prior to birth.Neonates from the AD-ON research biobank, admitted to the Neonatal Intensive Care Unit at Nordsjaellands Hospital, were included in the AD-ON neonatal cohort. The neonatal cohort consisted of 149 neonates hereof 63 preterm and 86 term born. The children in the cohort have been invited to follow-up visits at age 1 and 6 years.

FINDINGS TO DATE

Published data from this cohort includes a validated and clinically applicable method to measure FeNO in neonates. We found an age-specific pattern of association between respiratory symptoms at age 1 and neonatal FeNO in preterm children. Moreover, we found that the respiratory symptoms risk was associated with postnatal factors (Respiratory Syncytial Virus infection and parental smoking) in preterm infants and prenatal factors (parental asthma and maternal infection during pregnancy) in term born infants.

FUTURE PLANS

In the future, the children will be examined continuously with 3-year to 5-year intervals until the age of 18. Lung function, allergy tests, environmental exposure measurements and questionnaires will be collected at each follow-up visit.

Population-based Incidence of Myopericarditis After COVID-19 Vaccination in Danish Adolescents

In this prospective nationwide multicenter study from Denmark, myopericarditis after Pfizer-BioNTech mRNA COVID-19 vaccination was identified in 13 males and 2 females between May 15 and September 15, 2021, among 133,477 vaccinated males and 127,857 vaccinated females 12-17 years of age, equaling 97 males and 16 females per million. In conclusion, the incidence of myopericarditis after COVID-19 vaccination among males appears higher than reports from the United States.

Transthoracic Vector Flow Imaging in Pediatric Patients with Valvular Stenosis - A Proof of Concept Study

Purpose Continuous wave Doppler ultrasound is routinely used to detect cardiac valve stenoses. Vector flow imaging (VFI) is an angle-independent real-time ultrasound method that can quantify flow complexity. We aimed to evaluate if quantification of flow complexity could reliably assess valvular stenosis in pediatric patients.

Materials and Methods Nine pediatric patients with echocardiographically confirmed valvular stenosis were included in the study. VFI and Doppler measurements were compared with transvalvular peak-to-peak pressure differences derived from invasive endovascular catheterization.

Results Vector concentration correlated with the catheter measurements before intervention after exclusion of one outlier (r=−0.83, p=0.01), whereas the Doppler method did not (r=0.49, p=0.22). The change in vector concentration after intervention correlated strongly with the change in the measured catheter pressure difference (r=−0.86, p=0.003), while Doppler showed a tendency for a moderate correlation (r=0.63, p=0.07).

Conclusion Transthoracic flow complexity quantification calculated from VFI data is feasible and may be useful for assessing valvular stenosis severity in pediatric patients.

[Preoperative risk assessment of patients with congenital heart disease in non-cardiac surgery]

Over the last decades, remarkable advances in survival in patients with congenital heart disease (CHD) have been reported. Currently, 90% of infants born with CHD can expect to reach adulthood. Moderate and severe CHD is associated with increased perioperative mortality. To ensure optimal management of CHD patients undergoing non-cardiac surgery, preoperative risk assessment is pivotal, along with a multidisciplinary approach and collaboration across hospitals. The objective of this review is to provide a simple model to identify CHD patients at risk prior to non-cardiac surgery.

Pediatric Transthoracic Cardiac Vector Flow Imaging - A Preliminary Pictorial Study

Purpose Conventional pediatric echocardiography is crucial for diagnosing congenital heart disease (CHD), but the technique is impaired by angle dependency. Vector flow imaging (VFI) is an angle-independent noninvasive ultrasound alternative for blood flow assessment and can assess complex flow patterns not visible on conventional Doppler ultrasound.

Materials and Methods 12 healthy newborns and 3 infants with CHD were examined with transthoracic cardiac VFI using a conventional ultrasound scanner and a linear array.

Results VFI examinations revealed common cardiac flow patterns among the healthy newborns, and flow changes among the infants with CHD not previously reported with conventional echocardiography.

Conclusion For assessment of cardiac flow in the normal and diseased pediatric heart, VFI may provide additional information compared to conventional echocardiography and become a useful diagnostic tool.

Corrected QT changes during antipsychotic treatment of children and adolescents: a systematic review and meta-analysis of clinical trials

OBJECTIVE

To evaluate the effect of antipsychotics on the corrected QT (QTc) interval in youth.

METHOD

We searched PubMed (http://www.ncbi.nlm.nih.gov/pubmed) for randomized or open clinical trials of antipsychotics in youth <18 years with QTc data, meta-analyzing the results. Meta-regression analyses evaluated the effect of age, sex, dose, and study duration on QTc. Incidences of study-defined QTc prolongation (>440-470 milliseconds), QTc >500 milliseconds, and QTc change >60 milliseconds were also evaluated.

RESULTS

A total of 55 studies were meta-analyzed, evaluating 108 treatment arms covering 9 antipsychotics and including 5,423 patients with QTc data (mean age = 12.8 ± 3.6 years, female = 32.1%). Treatments included aripiprazole: studies = 14; n = 814; haloperidol: studies = 1; n = 15; molindone: studies = 3; n = 125; olanzapine: studies = 5; n = 212; paliperidone: studies = 3; n = 177; pimozide: studies = 1; n = 25; quetiapine: studies = 5; n = 336; risperidone: studies = 23; n = 2,234; ziprasidone: studies = 10, n = 523; and placebo: studies = 19, n = 962. Within group, from baseline to endpoint, aripiprazole significantly decreased the QTc interval (-1.44 milliseconds, CI = -2.63 to -0.26, p = .017), whereas risperidone (+1.68, CI = +0.67 to +2.70, p = .001) and especially ziprasidone (+8.74, CI = +5.19 to +12.30, p < .001) significantly increased QTc. Compared to pooled placebo arms, aripiprazole decreased QTc (p = .007), whereas ziprasidone increased QTc (p < .001). Compared to placebo, none of the investigated antipsychotics caused a significant increase in the incidence of the 3 studied QTc prolongation measures, but there was significant reporting bias.

CONCLUSION

Based on these data, the risk of pathological QTc prolongation seems low during treatment with the 9 studied antipsychotics in otherwise healthy youth. Nevertheless, because individual risk factors interact with medication-related QTc effects, both medication and patient factors need to be considered when choosing antipsychotic treatment.

Quality of life and cognitive function in Fontan patients, a population-based study

BACKGROUND

After the Fontan procedure patients are at risk for reduced quality of life (QoL) and cognitive function. We aimed to assess these important factors in Danish Fontan patients and to compare the results with a group of healthy controls.

METHODS

All Fontan patients living in Denmark were identified and invited to participate. QoL was evaluated using the Pediatric Quality of Life Inventory (PedsQL) version 4.0 generic core module in patients <16 years and the Short Form 36 questionnaire (SF-36) in patients ≥16 years. Cognitive function was evaluated in all patients ≥6 years using the Quick Test of Cognitive Speed. To evaluate if QoL correlated with exercise capacity, patients performed a symptom-limited bicycle test.

RESULTS

158 of 179 eligible patients (88%) consented to participate. Median age was 13.9 years (IQR: 10.2-19.3). PedsQL scores increased with age but were significantly lower among patients than among controls. SF-36 physical scores were significantly lower in patients compared to controls while psychosocial scores were similar. Cognitive speed was significantly reduced in patients at all ages compared to controls. No significant difference in PedsQL-/SF-36 scores or cognitive speed was found between hypoplastic left heart syndrome (HLHS) and non-HLHS Fontan patient. PedsQL-/SF-36 scores in patients ≥10 years correlated significantly to cognitive speed but not to peak exercise capacity.

CONCLUSION

QoL is reduced in Fontan children compared to their healthy counterparts whereas in patients ≥16 years only physical, but not psychosocial QoL is reduced. Cognitive speed was significantly lower in patients at all ages compared to controls.

Thromboembolic complications in Fontan patients: population-based prevalence and exploration of the etiology

After the Fontan procedure, patients face an increased risk for thromboembolic events (TE). The etiology for this increased thrombogenecity is incompletely understood. This study aimed to determine the prevalence of TE in Danish Fontan patients and to bring new insights into the etiology of TE. Using a population-based design, we retrospectively identified all TEs in 210 Fontan patients. Whole blood assays (thromboelastography, thromboelastography functional fibrinogen and Multiplate) reflecting global hemostasis, clot strength and platelet aggregation were analyzed prospectively in 112 patients and plasma was analyzed in 76 patients for biomarkers reflecting endothelial-, glycocalyx-, platelet-, and fibrinolysis function (histone-complexed DNA fragments, Protein C, soluble CD40 ligand, soluble thrombomodulin, syndecan-1, tissue-type plasminogen activator). The results were compared in groups stratified according to age, antithrombotic therapy, TE, and glycocalyx degradation (syndecan-1 < or ≥ median). Correlation between biomarkers and demographic-, anatomical-, clinical- and biochemical parameters was investigated. The prevalence of TE was 8.1 % after a mean follow-up of 8.4 years. None of the stratified groups demonstrated evidence of hypercoagulability in the whole blood assays and no unexpected significant differences were found between the groups. All biomarkers, except protein C, correlated with one another and after stratification of glycocalyx degradation only syndecan-1 levels ≥ median correlated with other biomarkers. The prevalence of TEs was 8.1 % after mean follow-up of 8.4 years. Overall, the hemostatic profile appeared normal, however, in a subset of patients, evidence of some endothelial activation/damage including glycocalyx degradation and fibrinolysis was found, identifying a potentially more thrombogenic group.

Influence of Factor V Leiden on susceptibility to and outcome from critical illness: a genetic association study

INTRODUCTION

Disturbance of the pro-coagulatant and anti-coagulant balance is associated with a poor outcome from critical illness. The objective of this study is to determine whether the Factor V Leiden (FVL) mutation is associated with susceptibility to or death from critical illness.

METHODS

A genetic association study involving four case cohorts comprising two Gram negative sepsis, one invasive pneumococcal disease and one intensive care unit cohort with a total of 1,249 patients. Controls were derived from a population-based cohort study (N = 8,147). DNA from patients and controls was genotyped for the FVL mutation.

RESULTS

When all patients were investigated together no significant difference in the frequency of FVL mutation was observed compared with controls (odds ratio (OR), 1.03; 95% confidence interval (CI), 0.83 to 1.29). However, when stratified among patients admitted to intensive care (N = 237), susceptibility and the likelihood of long-term death was influenced by the FVL mutation. In adjusted logistic regression analysis, FVL carriers had an increased risk of ICU admission compared to non-carriers (OR 1.62; 95% CI, 1.08 to 2.42). In adjusted Cox regression analysis, FVL carriers were at increased risk of long-term death compared to non-carriers (relative risk 1.78; 95% CI, 1.13 to 2.81). FVL carrier status did not predict either susceptibility to or outcome from Gram negative, Escherichia coli or Streptococcus pneumoniae sepsis.

CONCLUSIONS

Overall, the FVL mutation did not appear to increase the risk of admission due to severe invasive infections. Nevertheless, in the subgroup of patients admitted to intensive care an increased risk and a poorer long-term outcome for individuals with critical illness were observed for FVL mutation carriers.

Superoxide dismutase 3 polymorphism associated with reduced lung function in two large populations

RATIONALE

Superoxide dismutase (SOD) 3 inhibits oxidative fragmentation of lung matrix components collagen I, hyaluronan, and heparan sulfate. Inherited change in SOD3 expression or function could affect lung matrix homeostasis and influence pulmonary function.

OBJECTIVES

To identify novel SOD3 polymorphisms that are associated with lung function or chronic obstructive pulmonary disease (COPD).

METHODS

Resequencing of 182 individuals identified two novel polymorphisms, E1 (rs8192287) and I1 (rs8192288), in a conserved region of the SOD3 gene of potential relationship to lung function. We next genotyped 9,093 individuals from the Copenhagen City Heart Study for the polymorphisms and recorded spirometry, and admissions and deaths due to COPD during 26-year follow-up. Finally, we validated our findings in a cross-sectional analysis of 35,635 individuals from the Copenhagen General Population Study.

MEASUREMENTS AND MAIN RESULTS

Genotyping the Copenhagen City Heart Study identified 35 E1/I1 homozygotes, 1,050 heterozygotes, and 8,008 noncarriers (Hardy-Weinberg equilibrium: P = 0.93). Using quadruple lung function measurements, we found that E1/I1 homozygotes had 7% lower FVC % predicted (P = 0.006) and 4% lower FEV(1) % predicted (P = 0.12) compared with noncarriers. In the Copenhagen General Population Study, E1/I1 homozygotes also had lower FVC % predicted than noncarriers (P = 0.03), confirming an association between E1/I1 genotype and reduced lung function. E1/I1 homozygotes had adjusted hazard ratios for COPD hospitalization and COPD mortality of 2.5 (95% confidence interval, 1.0-5.9) and 3.7 (95% confidence interval, 0.9-15), respectively; the results were independent of influence from the R213G allele of the SOD3 gene.

CONCLUSIONS

We identified two novel polymorphisms in a conserved region of the SOD3 gene and show that individuals that are homozygous for these polymorphisms have reduced FVC % predicted in two large, population-based studies.

Genetically increased antioxidative protection and decreased chronic obstructive pulmonary disease

RATIONALE

Increased oxidative stress is involved in chronic obstructive pulmonary disease (COPD); however, plasma and bronchial lining fluid contains the antioxidant extracellular superoxide dismutase. Approximately 2% of white individuals carry the R213G polymorphism in the gene encoding extracellular superoxide dismutase, which increases plasma extracellular superoxide dismutase 10-fold and presumably also renders bronchial lining fluid high in extracellular superoxide dismutase.

OBJECTIVE

We tested the hypothesis that R213G reduces the risk of COPD.

METHODS

We studied cross-sectionally and prospectively (during 24 yr) 9,258 individuals from the Danish general population genotyped for R213G.

MEASUREMENTS

We determined plasma extracellular superoxide dismutase concentration, pulmonary function and COPD diagnosed by means of spirometry or through national hospitalization and death registers.

MAIN RESULTS

In the general population, 97.5% were noncarriers, 2.4% were heterozygotes, and 0.02% were homozygotes. Among R213G noncarriers, extracellular superoxide dismutase plasma concentration was 148+/-52 and 142+/-43 ng/ml (mean+/-SD) in individuals with and without COPD (Student's t test, p=0.02). Among heterozygotes, corresponding concentrations were 1,665+/-498 ng/ml and 1,256+/-379 (p<0.001). The adjusted odds ratio for spirometrically diagnosed COPD in heterozygotes versus noncarriers was 0.5 (95% confidence interval: 0.3-0.9). After stratification, the equivalent adjusted odds ratio was 1.5 (0.3-6.6) among nonsmokers and 0.4 (0.2-0.8) among smokers (p value for interaction=0.10). The adjusted hazard ratio for COPD hospitalization or death during follow-up in heterozygotes versus noncarriers was 0.3 (0.1-0.8).

CONCLUSIONS

Extracellular superoxide dismutase R213G heterozygosity protects against development of COPD in the Danish general population. This was observed in smokers, but not in nonsmokers.

Factor V leiden homozygosity, dyspnea, and reduced pulmonary function

BACKGROUND

Factor V Leiden homozygosity predisposes patients to deep venous thrombosis and major pulmonary thromboembolism. Consequently, factor V Leiden homozygosity could, via unrecognized repeated minor pulmonary thromboemboli, cause chronic pulmonary disease. We tested the hypothesis that factor V Leiden homozygosity is associated with pulmonary symptoms and signs.

METHODS

We studied a general population sample of 9253 individuals from the Copenhagen City Heart Study who were examined in 1991-1994. Of these, 6475 participants were also examined in 1976-1978 and/or 1981-1983. End points were dyspnea and lung function.

RESULTS

Among 20 factor V Leiden homozygotes, a mean +/- SD of 32% +/- 11% had severe dyspnea compared with 6% +/- 0.3% of 8534 noncarriers (chi(2) test; P<.001). The corresponding adjusted odds ratio for severe dyspnea was 5.4 (95% confidence interval, 1.9-15.7). During follow-up, forced expiratory volume in 1 second and forced vital capacity were 5% to 10% lower in homozygotes vs noncarriers (analysis of variance; P = .003 and P = .03). The annual mean +/- SD loss of forced expiratory volume in 1 second and forced vital capacity was 39 +/- 8 mL/y and 35 +/- 8 mL/y in homozygotes vs 21 +/- 10 mL/y and 15 +/- 10 mL/y in noncarriers (t test; P = .03 and P = .04), respectively. Factor V Leiden heterozygosity (n = 699) did not influence pulmonary symptoms and signs.

CONCLUSION

We demonstrate a previously unrecognized clinical presentation of factor V Leiden homozygosity with severe dyspnea and decreased pulmonary function.

Methylenetetrahydrofolate reductase polymorphism (C677T), hyperhomocysteinemia, and risk of ischemic cardiovascular disease and venous thromboembolism: prospective and case-control studies from the Copenhagen City Heart Study

Hyperhomocysteinemia is associated with ischemic cardiovascular disease (ICD) and venous thromboembolism (VTE). We tested the hypothesis that methylenetetrahydrofolate reductase (MTHFR) C677T homozygosity with hyperhomocysteinemia is associated with ICD and VTE. First, 9238 randomly selected whites from the general population were followed for 23 years. Second, 2125 whites with ischemic heart disease and 836 whites with ischemic cerebrovascular disease were compared with 7568 controls from the general population. Plasma homocysteine was elevated 25% in homozygotes versus noncarriers (P &lt; .001) and 19% in ICD/VTE cases versus controls (P &lt; .001). In prospective studies adjusted hazard ratios for ICD and VTE for homozygotes versus noncarriers did not differ from 1.0. Furthermore, MTHFR C677T homozygosity was not associated with increased risk of ICD or VTE in subgroups after stratification for sex, age, cholesterol, high-density lipoprotein cholesterol, lipoprotein(a), fibrinogen, triglycerides, body mass index, smoking, diabetes mellitus, hypertension, and factor V Leiden genotype. Finally, in case-control studies odds ratios for ischemic heart disease and ischemic cerebrovascular disease in homozygotes versus noncarriers did not differ from 1.0. In conclusion, MTHFR C677T homozygosity with hyperhomocysteinemia is not associated with ICD or VTE; however, ICD/VTE is associated with hyperhomocysteinemia. Therefore, ICD and VTE may cause hyperhomocysteinemia, rather than vice versa.

Factor V Leiden and the risk for venous thromboembolism in the adult Danish population

BACKGROUND

Odds ratios for venous thromboembolism (deep venous thrombosis and pulmonary embolism) derived from case-control studies range from 3 to 16 for heterozygotes compared with noncarriers and up to 79 for homozygotes compared with noncarriers.

OBJECTIVE

To estimate risks for venous thromboembolism in the adult Danish population according to factor V Leiden genotype.

DESIGN

Cohort study with 23 years of follow-up.

SETTING

Adult Danish population.

PARTICIPANTS

9253 randomly selected individuals.

MEASUREMENTS

Hospitalization and death from venous thromboembolism, factor V Leiden genotype, and additional thromboembolic risk factors.

RESULTS

Adjusted hazard ratios in heterozygotes and homozygotes compared with noncarriers were 2.7 (95% CI, 1.8 to 3.8) and 18 (CI, 4.1 to 41) for venous thromboembolism overall, 2.4 (CI, 1.3 to 3.8) and 22 (CI, 0 to 60) for deep venous thrombosis, and 3.0 (CI, 1.7 to 4.9) and 11 (CI, 0 to 33) for pulmonary embolism. The lowest absolute 10-year risks for venous thromboembolism in factor V Leiden heterozygotes and homozygotes--0.7% (CI, 0.5% to 1.0%) and 3% (CI, 1% to 8%)--were found in nonsmokers younger than 40 years of age with a body mass index below 25 kg/m2; the corresponding highest risks--10% (CI, 7% to 14%) and 51% (CI, 13% to 100%)--were found in smokers older than 60 years of age with a body mass index above 30 kg/m2.

CONCLUSIONS

Hazard ratios for venous thromboembolism in factor V Leiden heterozygotes and homozygotes compared with noncarriers in the adult Danish population were approximately 3 and 18, respectively. The simultaneous presence of smoking, obesity, and old age resulted in absolute 10-year thromboembolic risks of 10% in heterozygotes and 51% in homozygotes.

Genetically reduced antioxidative protection and increased ischemic heart disease risk: The Copenhagen City Heart Study

BACKGROUND

Extracellular superoxide dismutase (EC-SOD) is an antioxidative enzyme found in high concentrations in the arterial wall. Two to three percent of all people in Denmark carry an R213G substitution, which increases plasma concentration 10-fold. This may reduce arterial wall EC-SOD concentrations, increase intimal LDL oxidation, and therefore may accelerate atherogenesis. Our primary hypothesis was that EC-SOD-R213G predisposes to ischemic heart disease (IHD). The secondary hypothesis was that EC-SOD-R213G offers predictive ability with respect to IHD beyond that offered by measurements of plasma EC-SOD and autoantibodies against oxidized LDL (oxLDL).

METHODS AND RESULTS

The primary hypothesis was tested in a prospective, population-based study of 9188 participants from The Copenhagen City Heart Study with 956 incident IHD events during 23 years of follow-up and retested cross-sectionally with independent case populations of patients with IHD (n=943) or ischemic cerebrovascular disease (ICVD) (n=617). Case populations were compared with unmatched IHD/ICVD-free control subjects from The Copenhagen City Heart Study (n=7992). The secondary hypothesis was tested by using a nested case-control study comparing patients with IHD (n=956) with age- and gender-matched control subjects (n=956). Age- and gender-adjusted relative risk for IHD in heterozygotes (n=221, 2.4%) versus noncarriers (n=8965, 97.6%) was 1.5 (95% CI, 1.1 to 2.1). Retesting confirmed this: Age- and gender-adjusted odds ratios for IHD was 1.4 (1.0 to 2.0) and for ICVD 1.7 (1.1 to 2.7). Additional adjustment for plasma EC-SOD produced an odds ratio for IHD in heterozygotes versus noncarriers of 9.2 (1.2 to 72), whereas adjustment for autoantibodies against oxLDL produced an odds ratio of 2.5 (1.2 to 5.3).

CONCLUSIONS

Heterozygosity for EC-SOD-R213G is associated with increased IHD risk. Genotyping offers predictive ability with respect to IHD beyond that offered by plasma EC-SOD and autoantibodies against oxLDL.

Platelet glycoprotein IIb/IIIa Pl(A2)/Pl(A2) homozygosity associated with risk of ischemic cardiovascular disease and myocardial infarction in young men: the Copenhagen City Heart Study

OBJECTIVES

We tested the hypothesis that platelet glycoprotein (GP) IIb/IIIa Pl(A2)/Pl(A2) homozygotes or Pl(A1)/Pl(A2) heterozygotes versus Pl(A1)/Pl(A1) noncarriers have increased risk of ischemic cardiovascular disease and myocardial infarction (MI), stratified for age and gender.

BACKGROUND

The GP IIb/IIIa Pl(A1)/Pl(A2) polymorphism influences aggregation of platelets; however, an association between ischemic cardiovascular disease and heterozygosity remains controversial, and association with homozygosity is largely unexplored.

METHODS

We genotyped the participants of the Copenhagen City Heart Study, a prospective cardiovascular investigation of the Danish general population (n = 9,149, 22-year follow-up) and assessed the risk of ischemic cardiovascular disease in heterozygotes or homozygotes versus noncarriers.

RESULTS

Of the participants, 70.0%, 27.3%, and 2.7% were noncarriers, heterozygotes, or homozygotes, respectively. Incidence of ischemic cardiovascular disease was 167 and 103 per 10,000 person-years in homozygous and noncarrier men (log-rank: p = 0.006), whereas this difference was not observed in women (p = 0.33) (genotype.gender interaction: p = 0.03). In homozygous versus noncarrier men <40 years of age, 40 to 50 years, and >50 years at entry, age-adjusted relative risks (RRs) of ischemic cardiovascular disease were 3.6 (1.4 to 9.0), 2.4 (1.3 to 4.6), and 1.0 (0.6 to 1.8), respectively (age.genotype interaction in men: p = 0.04); equivalent multifactorially adjusted RRs were 3.0 (1.1 to 8.0), 2.0 (1.0 to 3.9), and 1.0 (0.6 to 1.8), respectively. The corresponding age-adjusted RR values of MI in men were 5.2 (1.5 to 18), 3.5 (1.6 to 7.5), and 0.5 (0.1 to 1.5), respectively (age.genotype interaction in men: p = 0.002); equivalent multifactorially adjusted RRs were 3.8 (1.0 to 15), 3.1 (1.4 to 6.9), and 0.5 (0.2 to 1.5), respectively.

CONCLUSIONS

Pl(A2)/Pl(A2) homozygosity is associated with a three-fold and four-fold risk of ischemic cardiovascular disease and MI in young men.

Factor V Leiden: The Copenhagen City Heart Study and 2 meta-analyses

Factor V Leiden (FVL) is associated with venous thrombosis; however, an association between FVL and arterial thrombosis remains controversial. We investigated FVL as a risk factor for myocardial infarction (MI), ischemic stroke (IS), or non-MI ischemic heart disease (non-MI-IHD). The design was 3 case-control studies and 3 prospective studies with 21 years' follow-up. The setting was the general population in Copenhagen, Denmark. The participants for The Copenhagen City Heart Study were 20- to 95-year-old participants without cardiovascular disease (control population, n = 7907) or participants diagnosed with MI (n = 469), IS (n = 231), or non-MI-IHD (n = 365). In addition, 3 independent patient populations from Copenhagen University Hospital with MI (n = 493), IS (n = 231), or non-MI-IHD (n = 448) were included. We measured FVL genotype; major cardiovascular risk factors; and MI, IS, and non-MI-IHD incidence and prevalence. Prevalences of FVL heterozygotes and homozygotes in control subjects from the general population were 7.7% and 0.2%. Odds ratios and relative risks of MI in FVL carriers (heterozygotes + homozygotes) versus noncarriers were 1.24 (95% confidence interval [CI], 0.91-1.69) and 0.83 (0.58-1.20) in case-control and prospective studies, respectively. Corresponding risks for IS were 0.92 (95% CI, 0.56-1.53) and 0.68 (0.45-1.04), and for non-MI-IHD 1.01 (95% CI, 0.71-1.44) and 0.97 (0.66-1.42). Findings from The Copenhagen City Heart Study suggest that FVL is not associated with MI, IS, or non-MI-IHD.

Increased degradation of lipoprotein(a) in atherosclerotic compared with nonlesioned aortic intima-inner media of rabbits: in vivo evidence that lipoprotein(a) may contribute to foam cell formation

To investigate a potential role of lipoprotein(a) [Lp(a)] in foam cell formation, we have measured the degradation rates of Lp(a) and LDL in the rabbit aorta in vivo. Lp(a) (or LDL) was labeled with both 113I-TC and 125I and injected into 17 rabbits with extensive aortic atherosclerosis and into 16 rabbits without atherosclerosis. As the protein moiety of the doubly labeled lipoproteins is degraded, 131I-TC is trapped in the cell, whereas 125I diffuses out of the cell. Twenty-four hours after injection, 12 samples of the aorta and biopsies from 9 other tissues were removed. The degradation rate of Lp(a) (percent of plasma pool per gram tissue per day) was less than that of LDL in the adrenals and in the intestine. In contrast, degradation rates of Lp(a) and LDL were similar in liver, spleen, kidney, heart, lung, skeletal muscle, and adipose tissue. In nonlesioned aortic intima-inner media, the degradation rate of Lp(a) was 39% of that of LDL (t test: P <.05 in aortic arch and thoracic aorta), whereas the degradation rates of Lp(a) and LDL were similar in atherosclerotic aortic intima-inner media. Lp(a) degradation rates were markedly increased in atherosclerotic compared with nonlesioned aortic intima-inner media: 28.2+/-9.2 x 10(-7)% and 5.0+/-0.6 x 10(-7)% of the plasma pool per gram tissue per day in the intima-inner media of the proximal segment of atherosclerotic and nonlesioned aorta, respectively (t test: P <.01). These results suggest that the metabolism of Lp(a) is different from that of LDL in nonlesioned arterial intima, possibly reflecting that Lp(a) is degraded by LDL receptors in arterial intima less efficiently than LDL. The results also indicate that the degradation rate of Lp(a) is markedly increased in atherosclerotic lesions of rabbits, supporting the idea that Lp(a) contributes to foam cell formation during the development of atherosclerosis.

Oxidation of plasma low-density lipoprotein accelerates its accumulation and degradation in the arterial wall in vivo

BACKGROUND

The aim of the present study was to investigate whether oxidized LDL (ox-LDL) in the arterial intima could be derived from LDL already oxidized in plasma.

METHODS AND RESULTS

Rabbits received an intravenous injection of 125I-labeled normal LDL (N-LDL) mixed with 131I-labeled LDL that had been mildly oxidized through exposure to Cu2+. The aortic accumulation of undegraded labeled LDL was expressed as plasma equivalents and cakulated as radioactivity in the intima/inner media (cpm/cm2) divided by the time-averaged concentration of radioactivity in plasma (cpm/nL): for the thoracic aorta, the accumulation of undegraded ox-LDL in the intima/ inner media exceeded that of undegraded N-LDL by 286% (n = 6, P < .04), 863% (n = 7, P < .02), and 364% (n = 8, P < .01) after 1, 3, and 24 hours of exposure, respectively. There was a strong positive association between the extent of oxidation and the excess accumulation of undegraded ox-LDL compared with N-LDL (thoracic aorta; 3 hours of exposure: r = .97, n = 14, P < .00001). To measure degradation of N-LDL and ox-LDL, 125I-LDL labeled with 131I-tyramine cellobiose was injected intravenously 24 hours before the aortic intima/inner media was removed: for the thoracic aorta, the accumulation of degradation products from ox-LDL (n = 6) exceeded that from N-LDL (n = 6) by 301% (P < .04).

CONCLUSIONS

The present data suggest a novel mechanism: mildly oxidized LDL may circulate in plasma for a period sufficiently long to enter, accumulate, and be degraded in the arterial intima in preference to N-LDL.

Naproxen has greater antipyretic effect on Hodgkin's disease-related fever than no other tumours or infection

In 28 febrile patients with malignant lymphoma or leukaemia, the hourly temperatures were recorded following an oral dose of 125 mg naproxen (50% of normal single adult analgesic dose). 15 patients had clinical infection, and 13 had fever secondary to their malignant disease. Compared to controls, there was no significant antipyretic effect of 125 mg naproxen in infected patients, whereas this small dose in patients without infection had a significant effect. In the uninfected patients, the antipyretic effect was significantly more marked in fever related to Hodgkin's disease than to non-Hodgkin lymphoma or leukaemia. This selective antipyretic effect of a prostaglandin-synthesis inhibitor in tumour-related fever, especially in Hodgkin's disease, is unexplained but may be useful in the palliative treatment of patients with advanced disease.

Phase II trial of Prednimustine. Leo-1031 (NSC-134087) in acute non-lymphocytic leukemia

18 patients with acute non-lymphocytic leukaemia were treated with Prednimustine, a chlorambucil ester of prednisolone, as a single drug. 5 patients responded with falling blast counts in peripheral blood, but only 1 obtained a complete remission of 3 months' duration. Since the activity of Prednimustine is lower than that of other commonly used drugs in acute non-lymphocytic leukaemia, future studies should concentrate on other aspects, such as treatment of patients with steroid receptor-positive blast cells or other types of leukaemia.