Utilization and outcomes of rotational atherectomy in Sweden

Aim

To evaluate utilization and outcomes of rotational atherectomy (RA) using data from the Swedish Coronary and Angioplasty Registry (SCAAR)

Methods

We included 1476 patients with 2218 lesions who underwent RA from 2005 to 2016. To study temporal changes, the study period was divided into three equal time-periods, period A, B and C.

Results

Although the number of RA procedures increased 3-fold from 2005 to 2016, the rate of RA (of all PCI procedures) remained low (0.5% vs 1.2% in 2005 vs 2016). RA patients consisted a high-risk group, with advanced age and clustering of comorbidities. Over time, included patients were older and had a higher risk profile. Trans-radial access, drug eluting stent (DES) use and use of intravascular imaging significantly increased from period A to C whereas positioning of a temporary pacemaker or intra-aortic balloon pump declined. Unfractionated heparin became the main anticoagulant (52 vs 87%) and use of glycoprotein IIb/IIIa inhibitors declined (31 vs 12%, in period A vs C). Following RA, 11% of lesions were treated without stent (15 vs 15 vs 8%, in period A, B and C) (Rota-only). In lesions treated with a stent, a bare metal stent (BMS) was implanted in 39% vs 12% vs 2% and a new generation DES (N-DES) in 5 vs 75 vs 97% (period A vs B vs C) of lesions.

The 3-year cumulative rate of restenosis was 6.7% (122 events), (11.1 vs 7.1 vs 4.1% in period A vs B vs C). As compared to DES, rota-only (adjusted HR 2.71; 95% CI 1.69- 4.36) and BMS (adjusted HR 3.63; 95% CI 2.27- 5.81) were associated with significantly higher risk for restenosis. First generation DES were associated with numerically higher but not significantly different risk for restenosis as compared to N-DES (adjusted HR 1.31; 95% CI 0.74- 2.31).

The 3 year cumulative rate of major adverse cardiac events (MACE), including death, myocardial infarction (MI) or any restenosis was 30.6% (34.2 vs 31.4 vs 28.2%, in period A vs B vs C) and the corresponding numbers for all-cause mortality were 18.1% (18.9 vs 18.4 vs 17.0%). After adjustment for baseline characteristics and angiographic findings, RA in period A was associated with higher risk for MACE as compared to period C (adjusted HR 1.40; 95% CI 1.09- 1.79), due to higher risk for MI and restenosis. The difference disappeared when procedural characteristics, including DES use, were added to the model.

The rate of major in-hospital complications was 7.0%, including in-hospital death 1.3%, periprocedural MI 2.8%, perforation 1.1%, cardiac tamponade 0.7%, stroke 0.2% and major bleedings 2.1%. We found no significant differences over time.

Conclusion

During the studied period, RA remained a rare procedure, utilised in a highly selected population. Over time a declining rate of restenosis and MI after RA was observed, a finding that appeared to be mainly driven by an increased use of DES. The rate of major in-hospital complication remained low.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Boston Scientific International

Bayesian estimation of genetic variance and response to selection on linear or ratio traits of feed efficiency in dairy cattle

This study aimed to estimate genetic parameters of the linear trait genetic residual feed intake (RFI) and the ratio traits feed conversion ratio (FCR) and feed conversion efficiency (FCE) along with dry matter intake (DMI) and energy sink traits such as energy-corrected milk (ECM), body weight (BW), body condition score (BCS), and BW change (BWC) across different weeks in the first lactation of Danish Holstein cows. A second objective was to conduct a Bayesian analysis of direct and correlated superiority of the selected group when selecting on genetic RFI, FCR, or FCE. Feed intake and energy sink traits were recorded during wk 1 to 44 of lactation on 847 primiparous Danish Holstein cows. A Bayesian multivariate random regression animal model was used to analyze DMI, ECM, BW, and BCS in different weeks of lactation. Genetic RFI was obtained by conditioning DMI on ECM, BW, BCS, and BWC using genetic partial regression coefficients. The posterior distribution of the breeding values for FCR and FCE was derived from the posterior distribution of functions of "fixed" environmental effects and random additive genetic effects on DMI and ECM. Genetic superiority of the selected group was defined as the difference in additive genetic mean of the selected top individuals expected to be potential parents, and the total population after integrating genetic trends out of the posterior distribution of selection responses. Posterior means of heritability of genetic RFI ranged from 0.10 to 0.15, genetic variance of FCR and FCE ranged from 2.13 × 10^-3 to 3.2 × 10^-3 (kg² DMI/kg² ECM) and 6.11 × 10^-3 to 2.4 × 10^-2 (kg² ECM/kg² DMI), respectively. Selection against RFI showed a direct response of -1.01 to -2.23 kg/d RFI and correlated responses of -0.031 to -0.056 kg/kg for FCR, 0.104 to 0.160 kg/kg for FCE, and -0.316 to -1.057 kg/d for DMI in different weeks of lactation. Selection against RFI had no significant effect on production traits but selection for ratio traits reduced BW and BCS. Posterior means of genetic correlation between DMI and ratio traits were low. In conclusion, the Bayesian procedure allowed us to estimate genetic RFI without the need for separate multiple regression analysis and considered the non-normal posterior distribution of ratio traits. Selection against genetic RFI might be an effective means to improve feed efficiency compared with ratio traits for feed efficiency in dairy cattle.

P2238Prognostic value and incremental benefit of ischaemic myocardial burden subtended by non-invasive CT-derived fractional flow reserve (FFRCT) significant stenoses

Background

Fractional flow reserve derived from CT-coronary angiography (FFRCT) accurately identifies ischaemic vessels which may be associated with clinical outcomes. Its predictive value in grey zone FFRCT values between 0.7–0.8 is not defined. The technique permits estimation of burden of ischaemic myocardium subtended by FFRCT significant vessels.

Purpose

To evaluate the prognostic value and incremental benefit of FFRCT defined ischaemic myocardial burden when compared to FFRCT alone.

Methods

This is a subanalysis of NXT (Analysis of Coronary Blood-Flow Using CTA:Next-Steps), a prospective study of stable coronary artery disease (CAD) patients referred for invasive angiography (ICA) undergoing invasive FFR, CTA and FFRCT in whom treating physicians had been blinded to FFRCT results. Primary endpoint, defined as a composite of non-fatal myocardial infarction and any revascularisation, was determined in 206 patients (age 64±9.5 years, 64% male) and 618 vessels. Burden of ischaemic myocardium was defined as percentage of myocardium subtended beyond the point at which a vessel's FFRCT becomes ≤0.8 as estimated by APPROACH score (FFRCT-APPROACH). In significant FFRCT vessels, the predictive value and incremental benefit of FFRCT-APPROACH was compared with significant FFRCT (≤0.8) for primary endpoint as measured by area under the receiver operator characteristic curve (AUC). Significant ischaemic myocardial burden was defined as >10%. The incidence and relationship between the primary endpoint with each 10% increase in FFRCT-APPROACH and 0.05-unit decrease in FFRCT values ≤0.8 was determined.

Results

Significant FFRCT was identified in 52.9% of patients (109/206) and 29.3% of vessels (181/618). At 4.7 years median follow-up the incidence of the primary endpoint in vessels with significant FFRCT-APPROACH was 58.9% (96/163) which was comparable with vessels with significant FFRCT (55.2%,100/181; P=0.50). The predictive value of FFRCT-APPROACH for the primary endpoint was comparable with FFRCT (AUC 0.72 [95% CI 0.65–0.79] vs 0.71 [0.63–0.78], P=0.79). When combined, there was significant predictive improvement compared with FFRCT alone (AUC 0.77 [0.70–0.84]; P=0.01). The largest incremental benefit upon FFRCT was observed in vessels with FFRCT values in the grey zone between 0.70–0.80 (AUC 0.76 [0.65–0.86] vs 0.62 [0.48–0.74]; P<0.01). Each 10% increase in FFRCT-APPROACH (Adjusted-HR 1.36; 95% CI 1.16–1.60; P<0.001) and each 0.05-unit FFRCT decrease (Adjusted-HR 1.42; 1.19–1.70; P<0.001) were independently associated with significant increase in the incidence of the primary-endpoint.

Conclusion

In patients with stable CAD referred for ICA, the burden of ischaemic myocardium subtended by FFRCT significant vessels predicted non-fatal myocardial infarction and future revascularisation. This provided significant incremental benefit when used in combination with FFRCT particularly at FFRCT values in the grey zone between 0.7 to 0.8.

P4449Incident cardiovascular disease in patients with type 2 diabetes: Established cardiovascular disease versus traditional risk markers

Background/Introduction

It is well established that patients with both T2D and established cardiovascular disease (CVD) are at high-risk of a re-event and should be treated with either a glucagon-like peptide-1 (GLP-1) analogue or a sodium-glucose transporter-2 (SGLT-2) inhibitor. Other high-risk patients with T2D may also benefit from these treatments. Whether traditional risk markers can identify patients with T2D without CVD with a similar incidence of CVD events as patients with T2D with established CVD is unknown.

Purpose

To compare the CVD incidence in patients with T2D with and without established CVD, stratified according to mid-regional pro-atrial natriuretic peptide (MR-proANP), albuminuria, electrogardiogram (ECG), echocardiography and age, to identify patients without established CVD who are at high risk of a CVD event.

Methods

In this prospective cohort study, patients with T2D (n=921) from a specialized diabetes clinic were examined at baseline regarding the different risk markers. Increasing cut-offs for MR-proANP were analysed to identify high-risk patients. Albuminuria included both micro- and macroalbuminuria. An abnormal ECG was defined as the presence of ST-/T-changes, bundle branch block or atrial fibrillation, and an abnormal echocardiography was defined as either heart failure with preserved (HFpEF) or reduced (HFrEF) ejection fraction. Established CVD was reported at baseline as prior myocardial infarction, coronary revascularization, cerebrovascular disease or peripheral artery disease. Information regarding CVD events was retrieved through national registers and a CVD event was similarly defined as established CVD, but in addition also included hospitalisation for heart failure and CVD death.

Results

In total, 224 (24%) patients had established CVD at baseline. Median [interquartile range] of follow-up was 4.7 [4.0–5.3] years. The incidence of CVD events among patients with established CVD was 95.7 per 1000-person years. Using a cut-off for MR-proANP of 190 pmol/l revealed that patients with a value above had similar incidence (93.9 per 1000-person years) and was found in 47 of 697 (6.7%) patients without CVD. In contrast, patients without CVD and with albuminuria (146 of 685 (21.3%) patients) or abnormal ECG (147 of 679 (21.6%)) or abnormal echocardiography (221 of 618 (35.7%)) or an age>65 years (335 of 697 (35.7%)) had substantial lower incidence (47.1, 35.1, 32.7 and 33.7 per 1000-person years, respectively).

Kaplan-Meier curves

Conclusion(s)

In patients with T2D without established CVD, using a range of traditional risk markers, we were only able to identify a subgroup of patients with MR-proANP values above 190 pmol/l who had a similar high incidence of CVD as T2D patients with established CVD. This subgroup may benefit from treatment with a GLP-1 analog or a SGLT-2 inhibitor. In contrast, the presence of other traditional risk markers in T2D was not associated with risk of incident CVD similar to patients with established CVD.

Acknowledgement/Funding

Thermo Fisher Scientific (Germany) funded the MR-proANP kits

Primary health care: an opportunity for early identification of people living with undiagnosed HIV infection

OBJECTIVES

We aimed to determine the fraction of HIV-diagnosed individuals who had primary health care (PHC) contacts 3 years prior to HIV diagnosis and whether the risk of HIV diagnosis and degree of immunodeficiency were associated with the frequency of visits or procedures performed.

METHODS

We used data from national registries to conduct a population-based nested case-control study. Cases were individuals diagnosed with HIV infection in Denmark from 1998 to 2016. Population controls were extracted from the general population matched 13:1 on gender and age. We used conditional logistic regression. As there was a statistically significant interaction, analyses were further stratified by gender and Danish/non-Danish origin.

RESULTS

We identified 2784 cases and 36 192 controls. Ninety-three per cent of cases and 88% of controls attended PHC at least once in the 3 years prior to diagnosis, with a higher median number of visits to PHC (NVPC) for cases. We found a statistically significant positive association between NVPC and risk of subsequent HIV diagnosis in men and non-Danish women. A U-shaped association between NVPC and risk of HIV diagnosis among Danish women. No substantial association between NVPC and degree of immunodeficiency was found. Risk of HIV diagnosis and degree of immunodeficiency were weakly associated with type of procedures performed.

CONCLUSIONS

For most HIV-infected individuals, there seem to be many opportunities for earlier diagnosis in PHC. In men and non-Danish women, the risk of HIV diagnosis but not the degree of immunodeficiency was related to NVPC. The results suggest that the type of medical procedure performed cannot not be used as a guide by the primary physician to indicate which patients to test.

Short communication: Multivariate outlier detection for routine Nordic dairy cattle genetic evaluation in the Nordic Holstein and Red population

It is of practical importance to ensure the data quality from a milk-recording system before use for genetic evaluation. A procedure was developed for detection of multivariate outliers based on an approximation for Mahalanobis distance and was implemented in the Nordic Holstein and Red population. The general target of this procedure is based on the Nordic Cattle Genetic Evaluation yield model, which is a 9-trait model for milk, protein, and fat in the first 3 lactations. The procedure is based on the phenotypic correlation structure as a function of days in milk (DIM) and on computation of trait means and standard deviations within a production year, lactation, and DIM. For each record in the data, a Mahalanobis distance value was computed based on the trait mean and the covariance matrix for the actual production year, lactation, and DIM. A set of cutoff values, ranging from 10 to 100 with steps of 10, for discarding multivariate outliers was investigated. Prediction accuracy was calculated as the Pearson correlations between estimated breeding values predicted by full data set and estimated breeding values predicted by reduced data set for cows without records in the reduced data set and with 1 or more records deleted due to the editing rules on Mahalanobis distance. The results showed that, averaged over all scenarios, gains of 0.005 to 0.048 on prediction accuracy have been obtained by deleting the multivariate outliers. The improvements were more profound for progeny of young bulls compared with progeny of proven bulls. It is easy to implement this multivariate outlier-detection procedure in the routine genetic evaluation for different dairy cattle breeds; however, an optimal cutoff value for Mahalanobis distance needs to be defined to achieve an acceptable compromise between genetic evaluation accuracy and data deletion.

Vorkommen von Ehrlichia canis bei Hunden in Deutschland?

Gegenstand und Ziel: Retrospektive Untersuchung von Hunden auf eine autochthone Infektion mit E. canis in Deutschland. Material und Methode: In die Studie gingen 111 Hunde ein, die sich in eine symptomatische (n = 49) und eine asymptomatische (n = 62) Gruppe unterteilten. Bei allen Hunden erfolgten eine Antikörperbestimmung gegen Ehrlichia canis mittels Immunfluoreszenztest im Serum und ein Direktnachweis von Ehrlichia und Anaplasma spp. mittels PCR aus EDTA-Vollblut. Ausschlusskriterien waren ein Auslandsaufenthalt sowie die Vorbehandlung mit Tetrazyklinen, Chloramphenicol oder Imidocarb. Ergebnisse: Niedrige IFT-Antikörpertiter gegen E. canis konnten bei sieben Hunden (6,3%) festgestellt werden. Sechs Hunde gehörten der symptomatischen und ein Hund der asymptomatischen Gruppe an. Gleichzeitig wurden bei vier dieser Hunde sehr hohe und bei einem ein moderater Antikörpertiter gegen Anaplasma phagocytophilum gefunden. Das PCR-Screening für Ehrlichia und Anaplasma war lediglich in zwei Fällen positiv. Beide Male ließ sich A. phagocytophilum nachweisen. Schlussfolgerungen: Nur bei zwei für E. canis seropositiven Hunden konnten keine Kreuzreaktionen mit A. phagocytophilum nachgewiesen werden. Da ein Direktnachweis bei diesen zwei Hunden nicht möglich war, ist eine tatsächliche Infektion mit E. canis fraglich. Die Gefahr der autochthonen Infektion von Hunden mit E. canis in Deutschland scheint somit gering zu sein, ist aber nicht ausgeschlossen. Klinische Relevanz: Bei unspezifischen Symptomen wie Apathie, Fieber und Inappetenz sowie Laborveränderungen in Form von Anämie und/oder Thrombozytopenie sollte deshalb auch bei Hunden, die Deutschland nicht verlassen haben, an eine Infektion mit E. canis gedacht werden.

The value of a new cardiac magnetic resonance imaging protocol in Myocardial Infarction with Non-obstructive Coronary Arteries (MINOCA) - a case-control study using historical controls from a previous study with similar inclusion criteria

Background

Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) is common with a prevalence of 6% of all patients fulfilling the diagnosis of myocardial infarction. MINOCA should be considered a working diagnosis. Cardiac Magnetic Resonance (CMR) imaging has recently been suggested to be of great value to determine the cause behind MINOCA. The objectives of this paper are to describe the rationale behind the second Stockholm Myocardial Infarction with Normal Coronaries (SMINC-2) study and to discuss the protocol for investigation of MINOCA patients in the light of the recently published position paper from the European Society of Cardiology.

Methods

The SMINC-2 study is an open non-randomised study using historical controls for comparison. The primary aim is to prove that MINOCA patients investigated with the latest CMR imaging technique can achieve a diagnosis in 70% of all cases entirely by imaging. By including 150 patients we will have >80% chance to prove that the diagnostic accuracy can be improved by 20 absolute % with a p-value of less than 0.05 when compared with CMR imaging in the SMINC-1 study. Furthermore, in addition to invasive coronary angiography, coronary arteries are evaluated by computed tomography angiography to investigate coronary causes and questionnaires are used to describe Quality-of-Life (QoL). By January 1st 2017, 75 patients have been included.

Discussion

Whether CMR imaging can provide a diagnosis to an adequate proportion of MINOCA patients is unknown. Well-defined inclusion and exclusion criteria will be used to compare a MINOCA cohort from the population with an appropriate control group. Positive results are likely to influence future guidelines of the management of MINOCA. Furthermore, the study will give mechanistic insights into MINOCA in particular in patients with “true” myocardial infarction and describe QoL in this vulnerable group of patients.

Trial registration

Clinical Trials NCT02318498.

Joint analysis of longitudinal feed intake and single recorded production traits in pigs using a novel Horizontal model

A novel Horizontal model is presented for multitrait analysis of longitudinal traits through random regression analysis combined with single recorded traits. Weekly ADFI on test for Danish Duroc, Landrace, and Yorkshire boars were available from the national test station and were collected from 30 to 100 kg BW. Single recorded production traits of ADG from birth to 30 kg BW (ADG30), ADG from 30 to 100 kg BW (ADG100), and lean meat percentage (LMP) were available from breeding herds or the national test station. The Horizontal model combined random regression analysis of feed intake (FI) with single recorded traits of ADG100, LMP, and ADG30. In the Horizontal model, the FI data were horizontally structured with FI on each week as a "trait." The additive genetic and litter effects were modeled to be common across different FI records by reducing the rank of the covariance matrices using second- and first-order Legendre polynomials of age on test, respectively. The fixed effect and random residual variance were estimated for each weekly FI trait. Residual feed intake (RFI) was derived from the conditional distribution of FI given the breeding values of ADG100 and LMP. The heritability of FI varied by week on test in Duroc (0.12 to 0.19), Landrace (0.13 to 0.22), and Yorkshire (0.21 to 0.23). The heritability of RFI was lowest and highest in wk 6 (0.03) and 10 (0.10), respectively, in Duroc and wk 7 (0.04 and 0.02) and 1 (0.09 and 0.20), respectively, in Landrace and Yorkshire. The proportion of FI genetic variance explained by RFI ranged from 20 to 75% in Duroc, from 19 to 75% in Landrace, and from 11 to 91% in Yorkshire. Average daily gain from 30 to 100 kg BW and ADG30 heritabilities were moderate in Duroc (0.24 and 0.22, respectively), Landrace (0.34 and 0.25, respectively), and Yorkshire (0.34 and 0.22, respectively). Lean meat percentage heritability was moderate in Duroc (0.37) and large in Landrace (0.62) and Yorkshire (0.60). The genetic correlation of FI with ADG100 increased by week on test followed by a 32% decrease from wk 7 in Duroc and a 7% decrease in dam line breeds. Defining RFI as genetically independent of production traits leads to consistent and easy interpretable breeding values. The genetic parameters of traits in the feed efficiency complex and their dynamics over the test period showed breed differences that could be related to the fatness and growth potential of the breeds. The Horizontal model can be used to simultaneously analyze repeated and single recorded traits through proper modeling of the environmental variances and covariances.

Reliability of surface electromyography measurements from the suprahyoid muscle complex

Assessment of swallowing musculature using motor evoked potentials (MEPs) can be used to evaluate neural pathways. However, recording of the swallowing musculature is often invasive, uncomfortable and unrealistic in normal clinical practice. To investigate the possibility of using the suprahyoid muscle complex (SMC) using surface electromyography (sEMG) to assess changes to neural pathways by determining the reliability of measurements in healthy participants over days. Seventeen healthy participants were recruited. Measurements were performed twice with one week between sessions. Single-pulse (at 120% and 140% of the resting motor threshold (rMT)) and paired-pulse (2 ms and 15 ms paired pulse) transcranial magnetic stimulation (TMS) were used to elicit MEPs in the SMC which were recorded using sEMG. ≈50% of participants (range: 42-58%; depending on stimulus type/intensity) had significantly different MEP values between day 1 and day 2 for single-pulse and paired-pulse TMS. A large stimulus artefact resulted in MEP responses that could not be assessed in four participants. The assessment of the SMC using sEMG following TMS was poorly reliable for ≈50% of participants. Although using sEMG to assess swallowing musculature function is easier to perform clinically and more comfortable to patients than invasive measures, as the measurement of muscle activity using TMS is unreliable, the use of sEMG for this muscle group is not recommended and requires further research and development.

Global mRNA sequencing of human skeletal muscle: Search for novel exercise-regulated myokines

Objective

Skeletal muscle is an important secretory organ, producing and releasing numerous myokines, which may be involved in mediating beneficial health effects of physical activity. More than 100 myokines have been identified by different proteomics approaches, but these techniques may not detect all myokines. We used mRNA sequencing as an untargeted approach to study gene expression of secreted proteins in skeletal muscle upon acute as well as long-term exercise.

Methods

Twenty-six middle-aged, sedentary men underwent combined endurance and strength training for 12 weeks. Skeletal muscle biopsies from m. vastus lateralis and blood samples were taken before and after an acute bicycle test, performed at baseline as well as after 12 weeks of training intervention. We identified transcripts encoding secretory proteins that were changed more than 1.5-fold in muscle after exercise. Secretory proteins were defined based on either curated UniProt annotations or predictions made by multiple bioinformatics methods.

Results

This approach led to the identification of 161 candidate secretory transcripts that were up-regulated after acute exercise and 99 that where increased after 12 weeks exercise training. Furthermore, 92 secretory transcripts were decreased after acute and/or long-term physical activity. From these responsive transcripts, we selected 17 candidate myokines sensitive to short- and/or long-term exercise that have not been described as myokines before. The expression of these transcripts was confirmed in primary human skeletal muscle cells during in vitro differentiation and electrical pulse stimulation (EPS). One of the candidates we identified was macrophage colony-stimulating factor-1 (CSF1), which influences macrophage homeostasis. CSF1 mRNA increased in skeletal muscle after acute and long-term exercise, which was accompanied by a rise in circulating CSF1 protein. In cultured muscle cells, EPS promoted a significant increase in the expression and secretion of CSF1.

Conclusion

We identified 17 new, exercise-responsive transcripts encoding secretory proteins. We further identified CSF1 as a novel myokine, which is secreted from cultured muscle cells and up-regulated in muscle and plasma after acute exercise.

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Numerous transcripts were identified that were regulated in human skeletal muscle after acute and/or long-term exercise.

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These transcripts encode potential myokines, which may play key roles in local and systemic adaptations to exercise.

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CSF1 was identified as a novel myokine. CSF1 was increased after acute exercise, and secreted from cultured human myotubes in response to EPS.