Myocardial fibrosis associates with lupus anticoagulant in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that carries increased risk of cardiovascular disease; however, the underlying pathophysiological mechanisms remain poorly understood. We aimed to investigate the prevalence and degree of myocardial fibrosis in SLE patients and associated disease characteristics. Forty-nine SLE patients (89% female, mean age 52 ± 13 years, median disease duration 19 (11-25) years) and 79 sex-and age-matched healthy controls were included. CMR with T1 mapping was performed on SLE patients and healthy controls. Fifty-one SLE patients received gadolinium contrast for the evaluation of late gadolinium enhancement (LGE) and extra cellular volume (ECV). Multiple linear regression analyses were performed to investigate the association between markers of myocardial fibrosis on CMR (LGE, T1, ECV) and SLE-related variables [clinical disease activity, lupus nephritis, chronic kidney disease, anti-cardiolipin and/or anti-beta-2 glycoprotein I antibodies, and lupus anticoagulant (LAC)] with adjustment for traditional risk factors. T1 values were elevated in SLE patients compared to healthy controls (1031 ± 36 ms vs. 1019 ± 25 ms, p = 0.01). LGE was present in 20% of SLE patients who received gadolinium contrast. On multivariable analysis, LAC was associated with LGE in SLE patients (β = 3.87, p = 0.02). Neither T1 nor ECV associated with SLE disease characteristics; however, there was a trend towards an association between LAC and T1 (β = 16.9, p = 0.08). SLE patients displayed signs of myocardial fibrosis on CMR that were associated with the presence of LAC. These findings support the pathophysiological understanding of LAC as a mediator of microvascular and subsequent myocardial dysfunction.

Left ventricular size and function in patients with systemic lupus erythematosus associate with lupus anticoagulant: An echocardiographic follow-up study

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with increased risk of cardiac dysfunction. The pathophysiological mechanisms are poorly understood, and prognostic markers are warranted.

PURPOSE

We aimed to identify SLE-characteristics associated with measures of cardiac size and function during a five-year follow-up.

METHODS

We included 108 patients with SLE: 90% females, mean age 46 ± 13 years, median disease duration 14 (range 7-21) years. We performed blood sampling for potential biomarkers as well as a standard echocardiography at baseline and at a 5-year follow-up. To investigate associations with baseline and prospective 5-year changes in echocardiographic parameters, we performed multivariate regression analyses of SLE-related baseline variables (clinical disease activity, lupus nephritis, chronic kidney disease, anti-cardiolipin and/or anti-beta-2 glycoprotein I antibodies, and lupus anticoagulant (LAC)) and adjusted for traditional risk factors.

RESULTS

During follow-up, diastolic function regressed in two out of five echocardiographic measures (E/A ratio 1.4 ± 0.5 vs. 1.3 ± 0.5, p = 0.002; tricuspid regurgitation peak velocity 2.0 ± 0.6 vs. 2.2 ± 0.4 mmHg, p < 0.001). Left ventricular (LV) end-diastolic volume index increased (43.7 ± 13.9 vs. 52.5 ± 15.7 mL/m², p < 0.001). Left and right ventricular systolic function remained stationary. LAC was associated with inferior diastolic function: lower E/A ratio (p = 0.04) and higher E/e' ratio at baseline (p = 0.04) and increased left ventricular atrial volume index during follow-up (p = 0.01). LAC was further associated with LV dilatation during follow-up (p = 0.01).

CONCLUSION

Presence of LAC was associated with measures of diastolic function as well as progressive LV dilatation during the 5-year follow-up. Thus, LAC might be a predictor of cardiac dysfunction in SLE patients. LAC is known to have implications for the microvascular circulation, but the clinical significance of the present findings is yet to be elucidated.

Left ventricular mass quantification by echocardiography; a novel accurate and more reproducible 2D-method validated by cardiac magnetic resonance in humans and cardiac autopsy in pigs

Funding Acknowledgements

Type of funding sources: Public hospital(s). Main funding source(s): The research fund of The Heart Center at Rigshospitalet, Denmark

Background

Left ventricular mass (LVM) is a strong independent risk factor for adverse cardiovascular events, but conventional echocardiographic methods used to assess and monitor individuals are currently limited by poor reproducibility and accuracy.

Purpose

We aimed to develop and validate an echocardiographic method for LVM-quantification that is simple, reproducible and accurate.

Methods

Our ‘novel method’ (Figure) adds the left ventricular wall thickness (t) to the left ventricular end-diastolic volume acquired by endocardial tracings using the biplane method of discs. For development of the novel method, cardiac assessment was performed using echocardiography followed immediately by gold standard cardiac magnetic resonance (CMR) in 85 humans with different left ventricular geometries, ranging from patients with various cardiac disorders (n = 41) to individuals without known cardiac disorders (n = 44). We compared the novel two-dimensional (2D) method to various conventional one-dimensional (1D) and 2D methods as well as three-dimensional (3D) echocardiography. Validation against anatomical LVM by cardiac autopsy was performed in thirty-four Danish Landrace pigs, weight 47-59 kg. Echocardiography was performed during anaesthesia, the pigs were euthanised, the heart explanted, and cardiac autopsy was performed where the left ventricle was trimmed and weighed for autopsy LVM.

Results

In humans, the novel method had better reproducibility in intra-examiner (coefficients of variation (CV) 8.6% vs. 11.0-14.5%) and inter-examiner analysis (CV 9.0% vs. 10.2-19.6%) than any other method, including 3D (CV intra-examiner 14.3%, inter-examiner 16.6%). Accuracy of the novel method against CMR was similar to 3D (mean difference ± 95% limits of agreement, CV): Novel: 2 ± 50g, 15.4% vs. 3D: 2 ± 51g, 15.6%; and better than the 1D-method by Devereux (7 ± 76g, 23.0%). Feasibility for the novel method was 95%. Autopsy validation in pigs confirmed high reproducibility; intra-examiner (CV 8.7% vs. 9.1-11.4%) and inter-examiner-analysis (CV 8.7% vs. 8.8-10.0%). Accuracy of the novel method against autopsy LVM was better than for the conventional echocardiographic methods: Novel -1 ± 20g, 7.8% vs. Devereux 26 ± 37g, 11.3%. 3D-validation was not available in pigs.

Conclusions

The novel 2D-based method for LVM-quantification had better reproducibility than any other echocardiographic method. Accuracy was similar to 3D and better than any conventional method. Autopsy validation in pigs supported our findings amongst the human population. As endocardial tracings using the biplane method forms part of the standard echocardiographic protocol, the novel method can easily be integrated into any echocardiographic software without substantially increasing analysis time, and provides an equivalent yet simpler alternative to 3D echocardiography. Abstract Figure.

Lupus anticoagulant in patients with systemic lupus erythematosus is associated with lower E/A ratio and progressive left ventricular dilatation: a five-year follow-up study

Funding Acknowledgements

Type of funding sources: Public hospital(s). Main funding source(s): Copenhagen University Hospital

Background

Systemic lupus erythematosus (SLE) is an autoimmune disease with increased risk of cardiovascular complications such as coronary artery disease, myocarditis, pericarditis and valvular dysfunction. The pathophysiological mechanisms are poorly understood and clinical, biochemical and/or imaging markers to identify high risk patients are warranted.

Purpose

We aimed to identify SLE-characteristics that are associated with progressive cardiac dysfunction during a five-year follow-up period in patients with SLE.

Methods

A total of 147 patients with SLE were included from 2013 to 2014. All patients underwent standard echocardiography at baseline as well as a collection of blood samples, including a selection of biomarkers. Patients were invited to a five-year follow-up with a total of 108 patients (90 % female, mean age 46 ± 13 years, median disease duration of 14 (7-21) years) completing a full echocardiographic, laboratory, and clinical examination. Multivariate regression analyses with eight independent baseline variables of interest (age, sex, disease activity (SLEDAI-2K), lupus nephritis, ischemic heart disease (IHD), antiphospholipid antibodies (IgM and IgG), and lupus anticoagulant(LAC)) were performed as for the association with baseline echocardiographic parameters as well as for changes during follow-up. Only echocardiographic measurements that changed significantly (p &lt; 0.01) during follow-up were selected for the regression analyses. Left ventricular end-diastolic volume index (LVEDVI) and E/A ratio were log-transformed at baseline in the regression analyses due to non-normality.

Results

During a five-year follow-up period, LVEDVI increased from 43.5 ± 13.9 to 52.5 ± 15.7 ml/m2 (p &lt;0.001), and left ventricular diastolic measures declined (E/A ratio 1.4 ± 0.5 vs. 1.3 ± 0.5, p = 0.002; e’ velocity 12.8 ± 3.8 vs. 12.0 ± 3.7 ms, p = 0.02; mitral valve deceleration time 227.9 vs. 200.8 ms, p &lt; 0.001), except for E/e’ (7.5 ± 3.8 vs. 6.8 ± 3.4, p = 0.02). Left ventricular ejection fraction remained stationary (59.5 ± 6.8 vs. 59.6 ± 6.4 %, p = 0.81). In multivariate regression analyses, presence of LAC was significantly associated with progressive left ventricular dilation during the follow-up period (p = 0.003) but not with higher baseline levels (p = 0.64) (Fig. A1 & A2). LAC was associated with lower E/A ratio at baseline (p = 0.005) but did not predict a decrease of E/A ratio during follow-up (p = 0.24) (Fig. B1 & B2). IHD was associated with higher LVEDVI at baseline (p = 0.004), but not with further progression of dilation (p = 0.07).

Conclusion

Presence of LAC was associated with lower E/A ratio at baseline as well as progressive left ventricular dilation during a five-year follow-up period. Hence, LAC might be a predictor of progressive cardiac dysfunction in patients with SLE. LAC is known to have implications for the microvascular circulation, but the clinical significance of the present findings is yet to be elucidated. Abstract Figure A  Abstract Figure B

Multi-modality comparison of volumes and ejection fraction by echocardiography, cardiac magnetic resonance and cardiac computed tomography in various left ventricular geometries

Funding Acknowledgements

Type of funding sources: Public hospital(s). Main funding source(s): The research fund of the Heart Center, Rigshospitalet, Denmark

Background

Assessment of left ventricular (LV) volumes and function is crucial in managing patients. New imaging modalities are becoming more common. It is therefore important to compare them with the standard echocardiographic method that most treatments rely on and to determine if they are suitable for all LV geometries.

Purpose

The purpose was to compare end-diastolic volume (EDV), end-systolic volume (ESV) and LV ejection fraction (LVEF) for the three most common imaging modalities; echocardiography, cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT).

Methods

We included 85 subjects with various LV geometries; no cardiac disease (n = 44) and various cardiac disorders (n = 41). Cardiac assessment was performed using echocardiography followed immediately by CMR; re-examination after median 6 days, interquartile range 3-18 days using echocardiography followed immediately by CCT. We compared EDV, ESV and LVEF by three-dimensional echocardiography (echo-3D), CMR and CCT to echocardiographic biplane method of discs (echo-BP). The population was divided in four LV geometry profiles (normal, dilatation, hypertrophy, dilatation and hypertrophy) according to gender, age and indexed CMR-values of EDV and LV mass. We calculated inter-modality-ratios by dividing the values from echo-3D, CMR and CCT with echo-BP, to evaluate variances between the LV geometries.

Results

The figure demonstrates the agreement to echo-BP divided by geometry. Echo-3D had overall best agreement to EDV, ESV and LVEF. CMR overestimated both EDV and ESV. CCT overestimated EDV but not ESV. CCT overestimated LVEF by 4-16% in absolute values, whereas CMR and echo-3D had better agreement for LVEF. The correlation between echo-BP and echo-3D, CMR, and CCT, respectively was; EDV 0.91, 0.94, 0.90, ESV 0.86, 0.86, 0.79, and LVEF 0.40, 0.46, 0.38, all p &lt; 0.001. CMR especially overestimated EDV and ESV in "hypertrophy and dilatation" whereas CCT especially underestimated EDV and ESV in solely "hypertrophy", with larger overestimation of LVEF. ANOVA-analysis of inter-modality-ratios between LV geometries indicated significant variation for EDV but not ESV by echo-3D (F = 2.9, p &lt; 0.05 and F = 1.6, NS), no significant variation for EDV or ESV by CMR (F = 0.01 and 2.4, both NS), and significant variation for both EDV and ESV by CCT (F = 5.4, p &lt; 0.01 and 7.2, p &lt; 0.001). No significant variation for LVEF by echo-3D (F = 1.0, NS), but significant variation for CMR and CCT (CMR: F = 4.5, p &lt; 0.01 and CCT: F = 8.6, p &lt; 0.001) with slightly higher variation for CCT.

Conclusions

Echo-3D had the overall best agreement of volumes and LVEF, compared to echo-BP as a reference. CMR overestimated EDV and ESV whereas CCT overestimated EDV but not ESV, resulting in overestimation of LVEF by CCT but not CMR. In hypertrophic non-dilated LVs; CCT underestimated both EDV and especially ESV, with larger overestimation of LVEF. In general, CMR appears to be less dependent on LV geometry compared to echo-3D and CCT. Abstract Figure.

Feasibility, repeatability, and reproducibility of contemporary diastolic parameters and classification

PURPOSE

To evaluate feasibility, time of acquisition, retest repeatability and reproducibility of echocardiographic indexes and classification algorithms of diastolic function.

METHODS

A total of 356 patients were examined before coronary artery bypass-grafting and/or aortic valve surgery. A subgroup of 50 was examined with 3 successive echocardiograms in conditions reflecting daily clinical practice. Diastolic parameters were obtained and analysed according to previous (2009) and current (2016) guidelines. Acquisition and analysis time, plus intra- and inter-observer variability were assessed.

RESULTS

Feasibility of diastolic parameters was between 93 and 99%, except the maximal tricuspid regurgitation velocity (TR Vmax) (65%). Mean acquisition and analysis time were highest for left atrial volumes (141 ± 24 s) in contrast to other parameters which were obtained in approximately one minute. Mean 368 and 360 s were needed to classify diastolic function according to the 2009 and 2016 algorithms, respectively (non-significant). Reproducibility was overall moderate (Pearson r = 0.62 to 0.87), with TR Vmax having the highest (r = 0.62) and mitral valve E/A ratio the lowest (r = 0.87) variation. The 2009 algorithm resulted in more indeterminate cases than the 2016 algorithm. Inter-examiner analysis resulted in reclassification of 20 vs. 8 patients using the 2009 and 2016 algorithms, respectively.

CONCLUSION

Diastolic parameters are highly feasible and moderately reproducible, except TR Vmax. The 2016 algorithm is more restrictive than the 2009 algorithm in classifying patients with advanced stages of diastolic dysfunction. Time of acquisition according to the two guidelines is not significantly different.

Accuracy and sensitivity of three-dimensional echocardiography to detect changes in right ventricular volumes: comparison study with cardiac magnetic resonance

We aimed to investigate the ability of three-dimensional transthoracic echocardiography (3DE) to detect changes in RV volumes compared to cardiac magnetic resonance (CMR). Eighty-five subjects including 45 with no known cardiac disease and 40 patients with a variety of cardiac diseases were included. Two- and three-dimensional echocardiography as well as CMR of the RV was performed before and after infusion of on average two litres of saline. Examinations were analysed with estimation of RV dimensions, volumes and ejection fraction (RVEF). Intra- and inter-examiner variability was evaluated in 25 patients randomly selected from the cohort. Three-dimensional echocardiography underestimated volumes and RVEF compared to CMR with mean differences and 95% limits of agreement of 110.3 ± 59 mL for RV end-diastolic volume (RVEDV), 43.3 ± 32 mL for RV end-systolic volume (RVESV) and 3.5 ± 10.7% for RVEF. CMR was more reproducible than 3DE, with intra-observer coefficient of variation (CV) of 4% vs. 14.2% for RVEDV, 9.7% vs. 16.7% for RVESV and 6.3% vs. 8.6% for RVEF. The RVEDV, RVESV and RV stroke volume (RVSV) by CMR significantly increased after saline infusion by 15.3 ± 16.2 mL, 3.5 ± 14.2 mL and 11.8 ± 12.6 mL, respectively, as well as RVEF by 1.5 ± 4.6% (p < 0.05). However, 3DE was not able to detect any of these changes in RV volumes (p ≥ 0.05). Compared to CMR imaging of the RV, three-dimensional echocardiography appears unable and unreliable in detecting RV volume changes of less than 15%, highlighting the need for cautious utility of 3DE in these circumstances.