Egil Henriksen

Subacute bartonella infection in Swedish orienteers succumbing to sudden unexpected cardiac death or having malignant arrhythmias.

During the period 1979-92, an increasing number of sudden unexpected cardiac deaths (SUCD) occurred in young, Swedish, male elite orienteers. Myocarditis was the most common diagnosis in the 16 victims, and in 4 cases was also associated with fatty infiltration mimicking arrhythmogenic right ventricular cardiomyopathy (ARVC). Tissues from autopsies of 5 orienteers were tested for Bartonella by PCR targeting the gltA (citrate-synthase) gene. The products were then sequenced. Antibodies to B. henselae, B. quintana and B. elizabethae were measured by indirect fluorescence antibody assay. Bartonella spp. DNA was detected in the hearts of 4 deceased orienteers, and in the lung of a fifth deceased case. The sequences were close to B. quintana in 2 cases and identical to B. henselae in 3. Four of these 5 cases, as well as 2 additional cases of elite orienteers with ARVC, indicated antibodies to Bartonella. It is suggested that Bartonella-induced silent subacute myocarditis, eventually leading to electric instability, caused the increased SUCD rate among the Swedish orienteers. It is further suggested that Bartonella infection may be a major pathogenetic factor in the development of ARVC-like disease. Although the mode of transmission is unknown, both zoonotic/vector-borne and parenteral person-to-person transmission may be involved.During the period 1979-92, an increasing number of sudden unexpected cardiac deaths (SUCD) occurred in young, Swedish, male elite orienteers. Myocarditis was the most common diagnosis in the 16 victims, and in 4 cases was also associated with fatty infiltration mimicking arrhythmogenic right ventricular cardiomyopathy (ARVC). Tissues from autopsies of 5 orienteers were tested for Bartonella by PCR targeting the gltA (citrate-synthase) gene. The products were then sequenced. Antibodies to B. henselae, B. quintana and B. elizabethae were measured by indirect fluorescence antibody assay. Bartonella spp. DNA was detected in the hearts of 4 deceased orienteers, and in the lung of a fifth deceased case. The sequences were close to B. quintana in 2 cases and identical to B. henselae in 3. Four of these 5 cases, as well as 2 additional cases of elite orienteers with ARVC, indicated antibodies to Bartonella. It is suggested that Bartonella-induced silent subacute myocarditis, eventually leading to electric instability, caused the increased SUCD rate among the Swedish orienteers. It is further suggested that Bartonella infection may be a major pathogenetic factor in the development of ARVC-like disease. Although the mode of transmission is unknown, both zoonotic/vector-borne and parenteral person-to-person transmission may be involved.

Echocardiographic doppler assessments of left ventricular filling and ejection during upright exercise in endurance athletes

Doppler echocardiography was used to describe left ventricular filling and ejection during upright bicycle exercise in 24 healthy male endurance athletes. The transmitral pressure gradient was estimated and isovolumetric relaxation, filling and ejection time and transmitral and aortic flow velocities were measured at rest and during exercise. From rest to peak exercise (at a heart rate of 160 bpm), the mean left ventricular filling time was shortened by 73%, the ejection time by 31%, while the isovolumetric relaxation time was shortened by 62%. At peak exercise, the maximum aortic flow velocity almost doubled and the maximum transmitral flow velocity more than doubled, with a tenfold increase in the mean transmitral pressure gradient. The increase was significant (P<0·001) at each level of exercise. The left ventricular filling rate measured as volume per time was 185 ± 62 ml s−1 at rest and it increased to 986 ± 192 ml s−1 at peak exercise. This study demonstrates large changes in diastolic filling indices during upright exercise and it shows that the heart is able to increase its filling rate five times from rest to peak exercise.

Effect of menopause on left ventricular filling in 50-year-old women

Abstract In conclusion, our study shows menopause-related changes in Doppler indexes of LV filling, suggesting impaired LV filling in postmenopausal women.

Left ventricular systolic dysfunction in outpatients with peripheral atherosclerotic vascular disease: prevalence and association with location of arterial disease.

We aimed to determine the prevalence of left ventricular systolic dysfunction (LVSD) in outpatients with peripheral atherosclerotic vascular disease (PAVD). Further, the associations of stenotic internal carotid artery disease (SICAD) and lower extremity artery disease (LEAD) with LVSD were evaluated.

Mitral annulus motion compared with wall motion scoring index in the assessment of left ventricular ejection fraction.

The biplane disc summation method is the recommended echocardiographic procedure to determine left ventricular (LV) ejection fraction (EF). Assessment of mitral annulus motion (MAM) or wall motion scoring index (WMI) has been reported to be less dependent on image quality compared with the recommended method, and proposed as a surrogate to the disc summation method in calculation of LVEF. We aimed to compare MAM and WMI in the echocardiographic assessment of LVEF. In a randomly selected population-based sample of 75-year-old men and women in sinus rhythm (n = 409) MAM, as measured by M-mode, was compared with WMI, calculated as the mean value of wall motion scoring in 9 LV segments. LVEF, as measured by the biplane disc summation method was used as reference. The limits of agreement (mean difference +/- 1.96 SD) between LVEF and corresponding MAM values were -18 to +13 LVEF%, and between LVEF and corresponding WMI values were -12 to +13 LVEF%. The areas under the receiver operating characteristic curves for MAM and WMI to predict a LVEF < 50% were 0.892 and 0.998, respectively (95% confidence interval of the difference 0.062-0.149). The corresponding areas for MAM and WMI to predict a LVEF < 40% were 0.955 and 0.998, respectively (95% confidence interval of the difference 0.017-0.069). In conclusion, the ability of WMI to estimate LVEF was more favorable than MAM in this population-based sample of 75-year-old participants. The findings suggest that the WMI is preferable to MAM in estimating LVEF.

Interstudy heterogeneity of definitions of diastolic dysfunction severely affects reported prevalence

Aims The aim of this article is to examine how the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE) recommendations on the classification of diastolic dysfunction (DDF) are interpreted in the scientific community and to explore how variations in the DDF definition affect the reported prevalence. Methods and results A systematic review of studies citing the EACVI/ASE consensus document ‘Recommendations for the evaluation of left ventricular diastolic function by echocardiography’ was performed. The definition of DDF used in each study was recorded. Subsequently, several possible interpretations of the EACVI/ASE classification scheme were used to obtain DDF prevalence in a community-based sample (n = 714). In the systematic review, 60 studies were included. In 13 studies, no specification of DDF definition was presented, a one-level classification tree was used in 13, a two-level classification tree in 18, and in the remaining 16 studies, a DDF definition was presented but no grading of DDF was performed. In 17 studies, the DDF definition relied solely on early diastolic tissue velocity and/or left atrial size. In eight of these studies, a single parameter was used, in two studies the logical operator AND was used to combine two or more parameters, and the remaining seven studies used the logical operator OR. The resulting prevalence of DDF in the community-based sample varied from 12 to 84%, depending on the DDF definition used. Conclusion A substantial heterogeneity of definitions of DDF was evident among the studies reviewed, and the different definitions had a substantial impact on the reported prevalence of DDF.

Mitral annular excursion during exercise in endurance athletes

The aim of the present study was to quantify the left ventricular (LV) longitudinal motion during exercise at rest and during upright exercise in 24 healthy male endurance athletes. By using M‐mode and two‐dimensional echocardiography, the relative mitral annular motion and the absolute LV longitudinal axis was measured at end‐diastole and end‐systole at rest and during exercise. From rest to peak exercise at a heart rate of 160 beats per minute (bpm) the mitral annular motion increased in the septal and lateral annular borders by 68% and 49% respectively. At rest, mitral annular excursion was significantly (13%) higher in the lateral than in the septal wall but at peak exercise at a heart rate of 160 bpm there was no difference between the septal and lateral annular motion. The total end‐diastolic LV axial length did not increase from rest to peak exercise. In conclusion, during upright exercise, mitral annular motion increased significantly with no difference between the septal and lateral annular excursion at peak exercise. The absolute increase in mitral annular motion during exercise was explained by a decrease in axial end‐systolic length.

Long-term prognostic impact of left atrial volumes and emptying fraction in a community-based cohort

Objective We hypothesised that left atrial emptying fraction (LAEF) would predict long-term cardiovascular outcome in the general population and better so than left atrial (LA) volumes. Methods A community-based sample (n=740) in sinus rhythm prospectively underwent clinical evaluation, echocardiography and blood analyses including N-terminal pro B-type natriuretic peptide (NTproBNP). The LA maximum (LAVmax) and minimum volumes (LAVmin) were indexed to body surface area (LAVImax and LAVImin, respectively). LAEF was calculated as LAVmax-LAVmin divided by LAVmax. The participants were followed for a median of 4.9 years regarding incident cardiovascular events (cardiovascular death or hospitalisation because of myocardial infarction, heart failure or stroke). Cox regression models were used to evaluate the associations of LA volumes and LAEF with the outcome. Results In a multivariable beta regression model, including clinical and echocardiographic baseline characteristics, higher plasma levels of NTproBNP, higher E/e′ and left ventricular systolic dysfunction remained as independent determinants of a lower LAEF. After adjustment for baseline characteristics, including NTproBNP levels, LAEF (HR for 1 SD decrease 1.33, 95% CI 1.04 to 1.70, p=0.022), but not LAVImax (HR for 1 SD increase 0.88, 95% CI 0.70 to 1.10, p=0.25) or LAVImin (HR for 1 SD increase 1.02, 95% CI 0.83 to 1.27, p=0.83) remained independently associated with outcome. Conclusions In this community-based cohort, LAEF was a powerful predictor of incident cardiovascular events and its predictive ability was stronger than for LA volumes. Our findings suggest that LA dysfunction may represent a more advanced state of LA remodelling than LA enlargement.

GDF-15 and TRAIL-R2 are powerful predictors of long-term mortality in patients with acute myocardial infarction:

Background The Proximity Extension Assay proteomics chip provides a large-scale analysis of 92 biomarkers linked to cardiovascular disease or inflammation. We aimed to identify the biomarkers that best predicted long-term all-cause mortality in patients with acute myocardial infarction. Methods In this prospective cohort study, 92 biomarkers were analysed in 847 consecutive patients from the Västmanland Myocardial Infarction Study with a median follow-up of 6.9 years. Results The mean (± standard deviation) age of the patients was 70 (11.8) years and 32.7% were female. Two hundred and seven patients had died after follow-up. The biomarkers most strongly linked to all-cause mortality were growth differentiation factor 15 (GDF-15) and tumour necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL-R2). Cox regression analysis showed that GDF-15 (hazard ratio 1.25 per unit change, 95% confidence interval, 1.02–1.53, p = 0.031) and TRAIL-R2 (hazard ratio 1.37 per unit change, 95% confidence interval 1.12–1.67, p = 0.002) were independent predictors of long-term all-cause mortality after adjusting for age, gender, diabetes, previous myocardial infarction, stroke, heart failure, hypertension, smoking, hypercholesterolaemia, body mass index, ST-elevation myocardial infarction, left ventricular ejection fraction, troponin I, estimated glomerular filtration rate, N-terminal pro-brain natriuretic peptide and C-reactive protein. The combination of GDF-15 and TRAIL-R2 with established risk factors and biomarkers showed a discriminating accuracy of separating survivors from non-survivors with a cross-validated area under the receiving operating characteristics curve of 0.88 within five years. Conclusion GDF-15 and TRAIL-R2 were the most powerful Proximity Extension Assay chip biomarkers in predicting long-term all-cause mortality in patients with acute myocardial infarction.

Impact of left ventricular geometry on long-term survival in elderly men and women.

Adverse loading conditions and cardiac injury lead to remodelling of the heart into different patterns of left ventricular (LV) geometry. Geometry can be classified into LV hypertrophy (LVH), concentric remodelling (CR) or normal geometry (NG). The prognostic implications of the different geometric patterns have been extensively studied in middle‐aged subjects, but data are scarcer for elderly populations.