P360 Site specific phenotype of atherosclerotic lesions according to plaque location within the coronary tree, a CCTA based study

Funding Acknowledgements

Research grant PlaqueImage, contract number 26/01.09.2016, SMIS code 103544, Project funded by the European Union and the Government of Romania

Background

The coronary CT angiography (CCTA)-based differences in composition, morphology and vulnerability of coronary plaques (CPs), according to their location within the coronary tree, have not been investigated so far.

Purpose

We sought to perform a comparative analysis between plaques located at different levels within the coronary tree, to identify the differences in plaque composition, morphology, and vulnerability between the three major coronary branches.

Methods

We conducted a cross-sectional, observational study on 75 patients with stable coronary artery disease who underwent CCTA for assessment of coronary lesions that exhibited at least one vulnerable plaque (VP) in the coronary tree. After image acquisition, coronary plaque analysis was performed with the use of the Syngo.via Frontier (Siemens) software. Plaque analysis also included evaluation of presence of VM: low attenuation plaque – LAP; napkin ring sign – NRS; spotty calcifications – SC; positive remodeling – PR. VP were defined as lesions that presented at least 1 vulnerability marker (VM). In total, 90 coronary VPs located at the level of the left anterior descending (LAD; n = 30), circumflex (CXA; n = 30) and right coronary artery respectively (RCA; n = 30) were identified and analyzed.

Results

Lesions located in the RCA presented a significantly higher length (LAD - 18.67± 5.49 vs. CXA - 15.48 ±3.73 vs. RCA - 20.47 ± 5.97 mm, p = 0.001), a higher degree of stenosis (LAD - 57.77 ± 8.62 vs. CXA - 54.50 ± 11.25 vs. RCA - 59.63 ± 10.42 mm, p = 0.022), and were more voluminous (LAD - 187.9 ± 86.03 vs. CXA - 146.9 ± 102.4 vs. RCA - 248.1 ± 11.4 mm3, p = 0.0007) compared to those located in the LAD and CXA, but no difference was observed regarding the remodeling (p = 0.180) or eccentricity indexes (p = 0.423). Plaque composition was also significantly different according to plaque location: calcified volume (LAD - 44.07 ± 63.90 vs. CXA - 12.40 ± 19.65 vs. RCA - 33.69 ± 34.38 mm3, p = 0.002), non-calcified volume (LAD - 143.8 ± 76.02 vs. CXA - 134.5 ± 102.2 vs. RCA - 214.4 ± 99.67 mm3, p = 0.002), lipid rich volume (LAD - 14.95 ± 22.69 vs. CXA - 6.44 ± 13.42 vs. RCA -16.07 ± 15.74 mm3, p = 0.0005), fibrotic volume (LAD - 128.9 ± 66.10 vs. CXA - 128.1 ± 91.56 vs. RCA - 198.3 ± 92.34 mm3, p = 0.003). The highest number of VM per plaque was present in the LAD (LAD - 2.2 ± 0.8 vs. CXA - 1.6 ± 0.7 vs. RCA - 1.8 ± 0.6, p = 0.01), as well as highest rate of VPs (LAD – 80%, CXA – 46.6%, RCA – 70%, p = 0.01). No difference was registered between coronary arteries on the presence of SCs (p = 0.670), NRS (p = 0.455), PR (p = 0.833), but LAPs were more frequently located in the LAD (p = 0.0009).

Conclusions

Coronary plaques located in the RCA were more voluminous and exhibited a higher volume of lipid rich and non-calcified atheroma. However, compared to the RCA and CXA, the left anterior descending artery presented CPs with a more expressed degree of vulnerability, a higher number of vulnerability markers per plaque, and a higher incidence of LAP.

P1434 Evolution of coronary wall shear stress following implantation of bioabsorbable vascular scaffolds - first results of a 1-year follow-up pilot study

Funding Acknowledgements

This research has been funded by the research grant PlaqueImage, contract number 26/01.09.2016, SMIS code 103544, Project funded by the European Union

Aims

Coronary shear stress (CSS) has been recently recognized to play a significant role in coronary plaque progression and vulnerabilisation. However, the evolution of CSS after implantation of different types of coronary stents is still under investigation. The aim of this study was to assess the evolution of the CSS along the coronary lesions following implantation of bioabsorbable vascular scaffolds (BVS), to determine the impact of BVS on coronary flow haemodynamics.

Methods and results

This was a single center prospective pilot study which enrolled 15 patients (aged 58.35 +/- 7.79 years, 13 males) with coronary artery disease undergoing BVS implantation in a major epicardial vessel. In all patients, angio CT scanning (Siemens Somatom Sensation scanner, Erlangen, Germany) was performed prior to the BVS implantation and repeated after 12 months. Lumen information was extracted from the vessels of interest and coronary rest hemodynamics, including CSS, were calculated using a computational fluid dynamics solver. All shear stress calculations were performed at baseline and repeated after 1 year. Average CSS was determined proximally, distally, and at the level of the minimal lumen area (MLA). Average CSS along the stented segment significantly decreased after BVS implantation, from 2.87 +/- 1.64 Pa at baseline to 1.9 +/- 0.49 at 1 year (p = 0.0001). Maximum CSS along the segment also exhibited a significant decrease, from 11.78 +/- 10.06 Pa to 6.35 +/- 3.08 Pa (p = 0.0009). Proximally to the MLA, CSS significantly decreased after BVS implantation, from 3.39 +/- 1.93 Pa at baseline to 1.91 +/- 0.68 Pa at 1 year (p <0.0001). However, this decrease in CSS was not significant distally to the MLA (1.3 +/- 0.72 Pa vs 1.59 +/- 0.65 Pa, p = 0.9).

Conclusions

Implantation of BVS leads to a significant decrease of CSS after 1 year, especially within coronary segments located proximally to the stenosis. This underlines the role of BVS in re-establishing a physiological pattern of coronary flow in diseased coronary vessels. The feature (mentioned herein) is not commercially available. Due to regulatory reasons its future availability cannot be guaranteed.

P674 Epicardial fat volume is associated with the risk of atrial fibrillation recurrence following pulmonary vein isolation

Funding Acknowledgements

Plaqueimage

Background

Atrial fibrillation (AF) is the most common supraventricular rhythm disturbance and pulmonary vein (PV) isolation has an important role in rhythm control treatment strategies of this disease. Various anatomical and clinical characteristics have been well established as predictors of the risk of recurrence following ablation procedures, but the role of epicardial fat tissue (EFT) in the recurrence of AF has not been elucidated so far.

Purpose

To investigate the influence of left atrial size and EFT volume in the recurrence of AF after pulmonary vein ablation, during a 6-month follow-up.

Methods

A total of 40 patients, 52.5% with paroxysmal and 47.5% with chronic AF underwent PV isolation using radiofrequency and cryoablation techniques. EFT was determined using cardiac computed tomography angiography (CCTA) associated with advanced image post-processing techniques.

Results

In patients who developed AF recurrence at 6 months after AF ablation, the volume of EFT and of left atrium were significantly larger than in the group who maintained sinus rhythm (202.5 ± 64.56 ml vs. 138 ± 55.74 ml, p = 0.01 for EFT, and 149.3 ± 4.66 ml vs. 90.63 ± 5.19 ml, p <0.0001 for left atrial volume, respectively). The left ventricular ejection fraction was significantly lower in patients with AF recurrence (50.25 ± 6.54% vs. 54.22 ± 3.95%, p = 0,04). The analysis of AF recurrence between the two different ablation techniques did not show any difference in recurrence rates between radiofrequency and cryoablation methods (29% vs. 23%, respectively p = 0.73). At the same time, recurrence rates after AF ablation were not influenced by the main cardiovascular risk factors (age, hypertension, dyslipidemia and smoking) and was not associated with different risk scores (CHA2DS2-VASc and HAS-BLED).

Conclusion

Patients with AF recurrence after pulmonary vein ablation present significantly higher EFT or left atrial volumes compared to patients who maintained sinus rhythm. This indicates the inflammatory mediated response, usually accompanied by an increased amount of EFT, could be associated with the risk of AF recurrence following catheter ablation of the pulmonary veins.

P1437 Integrated ST segment elevation score as a new predictor of the myocardial scar extent determined with LGE-CMR at 1-month follow-up after STEMI

Funding Acknowledgements

Funded by the research grant PlaqueImage, contract number 26/01.09.2016, SMIS code 103544, by the European Union and the Government of Romania

Background

The inflammatory response in the acute phase of a myocardial infarction, as well as in later phases contributes to the healing process of the infarcted myocardium and the left ventricular remodeling. Restoration and improvement of LV function highly depends on the magnitude of scar formation. Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) imaging has been validated for an accurate determination of the myocardial scar size and transmurality. The recovery of ST segment elevation is a liable marker of vessel patency following PCI.

Purpose

The aim of the study was to validate a new integrated score of ST segment elevation score (ISSTE) as a new predictor of the myocardial scar tissue size, in relation with increased inflammatory biomarkers, with the extent of myocardial fibrosis at one month, assessed with LGE-CMR, after STEMI.

Methods

We included 65 patients with STEMI who underwent urgent revascularization with PCI in the first 12 hours from the onset of symptoms. The ISSTE was determined by summing the ST segment elevation in all registered ECG leads at presentation (ISSTE-1) and at 2 hours (ISSTE-2) after primary PCI. Blood samples were also collected at baseline and day-5 for determination of serum hs-CRP levels. At 1-month follow-up all patients under LGE-CMR (1.5T scanner) for evaluation of the myocardial scar extent (volume, percentage, transmurality).

Results

ISSTE-2 was significantly correlated with day-5 hs-CRP serum levels (r = 0.546, 95%CI: 0.030-0.832, p = 0.037), although no significant correlations were noted with baseline hs-CRP levels (r= 0.238, p = 0.407). There were no significant correlations between ISSTE-1 score and the myocardial scar percentage (r = 0.241, p = 0.11) or high transmurality volume (r = 0.194, p = 0.21), while ISSTE-2 significantly correlated with myocardial scar mass (r = 0.406, 95%CI: 0.107-0.637 p = 0.007) and high transmurality volume (r = 0.344, 95%CI: 0.0320-0.596, p = 0.0273). The restoration of the ST segment, reflected by the difference between ISSTE-1 and ISSTE -2 is correlated with the infarct size mass (r = 0.336, 95%CI: 0.0307 -0.584, p = 0.027).

Conclusion

The magnitude of ST segment elevation determined at 2 hours after PCI was associated with the inflammatory response at day 5 after STEMI and it may serve as a predictor for the extent of the myocardial scar tissue determined with LGE-CMR at 1 month following STEMI. The ISSTE-1 score calculated at presentation does not reflect extent of the affected myocardial tissue following PCI.

P1823 Feasibility of CCTA in assessment of luminal changes and coronary shear stress evolution after implantation of bioresorbable vascular scaffolds

Funding Acknowledgements

PlaqueImage - financed by the National Authority of Scientific Research and Innovation and the Romanian Ministry of European Funding

Background

Coronary shear stress (CSS) is a well-established local mechanical factor in atherogenesis, progression and destabilization of atherosclerotic plaques. Analysis of CSS after coronary stent placement is still lacking of large clinical studies. Purpose: The aim of this study was to: (1) test the feasibility of Coronary Computed Tomography Angiography (CCTA) for assessment of local hemodynamic and luminal changes after implantation of bioresorbable vascular scaffolds (BVS), and (2) to investigate CSS modifications after BVS implantation. Methods: We conducted a single center, prospective pilot study on 73 patients with coronary artery disease who underwent elective percutaneous coronary intervention (PCI); group 1 (n = 30) – patients with BVS and group 2 (n = 43) – patients with bare metal stent (BMS) implanted. CCTA scanning was performed in all patients prior PCI and at 12 months after PCI. The mean CSS at proximal and at distal part of the stented segment and at the level of the minimal lumen area (MLA) was calculated at baseline and at 12 months after BVS placement. Results: CCTA revealed a higher incidence of severe coronary stenosis in group 1 (73%) than in group 2 (30%) (p < 0.0001). Sensibility of visual evaluation for identification of in-stent restenosis on CCTA was increased in BVS group (94%) than in BMS group (76.19%) (p = 0.0006), hence the group 1 had lower incidence of non-diagnostic evaluations. Mean CSS at the stented site was significantly lower at 12 months (1.9 +/- 0.68 Pa) that average CSS at baseline (2.87 +/- 3.08 Pa) (p = 0.0001). CSS analysis showed also a significantly decreased values at proximal level from 3.39 +/- 1.93 Pa at baseline to 1.91 +/- 0.68 Pa at follow up (p < 0.0001), but not a significant decrease at distal part – 1.3+/-0.72 Pa at baseline and 1.59 +/- 0.65 Pa at 12 months follow up (p = 0.9). Conclusions: CCTA is a feasible technique for assessment of luminal changes following BVS implantation. BVS implantation contribute to the improvement of local hemodynamics by restoring physiological pattern of coronary flow, as demonstrated by the computational fluid hemodynamics assessment of coronary circulation.

P977 CT phenotype of high-risk atherosclerotic plaques causing an acute coronary syndrome compared to silent vulnerable plaques

Funding Acknowledgements

PlaqueImage.- research grant no. 103544/2016, contract number 26/01.09.2016 -

Background

Previous studies demonstrated that plaque morphology has a crucial role in the development of an acute coronary syndrome (ACS). However, not all vulnerable coronary plaques produce an ACS and the prediction power of various vulnerability features to predict an acute coronary event in a close future, has not been elucidated so far.

Objective

We aimed to use multi-slice computed tomography angiography (CTA) for assessment of morphological characteristics of culprit lesions producing an ACS in the next several months after CT assessment, in comparison with morphological characteristics of unstable coronary atherosclerotic plaques which did not trigger an ACS.

Material and methods

We analyzed 40 patients in whom CTA revealed presence of unstable coronary lesions, exhibiting at least one marker of vulnerability: napkin ring sign (NRS), spotty calcium (SC), positive remodeling (PR) or presence of low attenuation plaque (LAP), divided in 2 groups: group 1 - 20 patients who developed an ACS in the next 6 months following CTA examination, and group 2 – 20 patients matched for age, gender and risk factors, who did not present any cardiovascular event 6 month after CTA assessment. Post-processing of multi-slice CTA images was performed in order to assess morphological characteristics and CT-derived markers of atherosclerotic plaque instability.

Results

Similar mean values of plaque length (17.1 +/- 5.9 mm vs 16.9 +/- 3.4 mm; p = 0.6) and total atheroma volume (188.1 +/- 104.7 mm3vs 186.4 +/- 90.7 mm3; p = 0.8) were obtained for both groups. The mean number of vulnerability markers was 1.6 in group 1 vs 1.2 in group 2 (p = 0.07). However, atherosclerotic lesions in patients from group 1 presented significantly higher values of lipid-rich atheroma (9.8 +/- 10.8 mm3vs 2.6 +/- 1.0 mm3; p = 0.01) and remodeling index (1.14 +/- 0.3 in group 1 vs 0.89 +/- 0.19 in group 2, p = 0.04). At the same time, atheromatous plaques in patients who developed an ACS during the 6-months follow-up showed in a significantly higher proportion LAP (45% in group vs 10% in group 2, p = 0.03) and PR (15%in group 1 versus 5% in group 2, p = 0.04), but not NRS (30% vs 25%, p = ns) or SC (65% vs 40%, p = 0.2).

Conclusions

Atherosclerotic plaques producing an ACS exhibit a different phenotype than unstable plaques that remain silent. The CTA profile of atheromatous plaques producing an ACS includes the presence of low attenuation, positive remodeling, higher RI and lipid-rich atheroma. Presence of these features in high-risk coronary plaques identifies very high risk patients, who can benefit from adapted therapeutic strategy in order to prevent the development of an ACS.

P657 Deterioration of left ventricular performance in response to pulmonary hypertension, in patients with scleroderma versus patients with coronary artery disease

Funding Acknowledgements

PlaqueImage

Background

The relationship between the degree of pulmonary hypertension (PH) and left ventricular performance in patients with systemic sclerosis is still a controversial issue in the literature. We aimed to conduct a comparative analysis of indexes characterizing left ventricular systolic and diastolic function, in two etiological types of pulmonary hypertension involving different pathophysiological mechanisms: PH caused by systemic sclerosis and PH caused by myocardial ischemia.

Material and method

We performed a prospective study on 83 patients (36 patients with documented PAH with a systolic pulmonary arterial pressure – sPAP of >35 mmHg and 47 subjects with normal sPAP), out of which group 1 – with systemic sclerosis (n = 48); group 2 – significant coronary artery disease - CAD (n = 35). Patients of each group were divided in two subgroups based on the diagnosis of PH: group 1A - subjects with scleroderma and associated PH (n = 20), group 1B - subjects with scleroderma without PH (n = 28), group 2A - ischemic patients with associated PH (n = 16) and subgroup 2B - patients with ischemic disease without PH (n = 19).

Results

Patients in group 1 presented a significantly higher number of female subjects (p = 0.001) and a higher mean age (p = 0.009) compared to group 2. Patients with associated PH presented a significantly lower left ventricular ejection fraction (LVEF) compared to those without PH within the ischemic group (p = 0.023). There was a significant inverse correlation between the sPAP and LVEF in ischemic patients (r=-0.52, p = 0.001) as well as for scleroderma patients without PH (r=-0.51, p = 0.04). Tissue Doppler analysis of the left ventricular function indicated a significant negative correlation between the septal E’ value versus the sPAP and lateral E’ value versus the sPAP (r=-0.49, p = 0.002; r=-0.43, p = 0,008).

Conclusions

Intrinsic myocardial damage plays an important role in left ventricular systolic function even in the absence of PAH. Scleroderma patients present a less pronounced deterioration of the LVEF in response to pulmonary hypertension, indicating that in this group, additional compensatory mechanisms could be involved in the complex response of myocardium to elevated pulmonary pressures.

P821 Influence of periplaque fat on coronary plaque vulnerability, a comparative analysis between atherosclerotic lesions located in the right versus left coronary arteries

Funding Acknowledgements

Research grant PlaqueImage, contract number 26/01.09.2016, SMIS code 103544, Project funded by the European Union and the Government of Romania

Background

The role of epicardial adipose tissue on coronary plaque vulnerability has been well established. However, the role of periplaque fat (PPF) has not been elucidated so far. Moreover, there is scarce data on the role of plaque location, in relation to peri-atheromatous adipose tissue on the vulnerability degree and morphology of coronary atherosclerotic lesions.

Purpose

To evaluate the influence of PPF on coronary plaque vulnerability, in a comparative analysis between atherosclerotic lesions located in the right and left coronary arteries.

Methods

This is an observational study which included 82 patients with stable CAD, who underwent 128-multislice CT coronary angiography, presented at least one coronary lesion with at least 50% degree of stenosis and exhibited ≥1 vulnerability markers in the respective coronary plaque. Plaques presenting features of vulnerability (spotty calcifications – SC, Napkin ring sign – NRS, low attenuation plaque – LAP, positive remodeling – PR), were defined as vulnerable plaques (VP). Image postprocessing was performed with the Syngo.via Frontier software and PPF was measured 10 mm around the analyzed VP. Based to the plaque location within the coronary tree, the study subjects were divided into: group 1 (location of VP in the right coronary artery - RCA) - n = 17; group 2 (location of VP in the left coronary artery - LCA) - n = 65.

Results

The analysis of the plaque characteristics indicated that the VPs from the RCA were significantly longer (20.81± 6.45 vs. 17.37 ± 4.59 mm, p = 0.02) and had a larger volume (269.3± 120.4 vs. 161.6 ± 80.89 mm3, p < 0.0001) compared to the VPs from the LCA. Compared to group 2, coronary plaques in group 1 exhibited a higher vulnerability degree, illustrated by a larger non-calcified volume (232.5 ± 111 vs. 134.5 ± 83.29 mm3, p = 0.0006), lipid-rich volume (19.4 ± 19.07 vs. 10.27 ± 17.08 mm3, p = 0.0106), and fibro-fatty volume (213 ± 101.3 vs. 124.2 ± 7.98 mm3, p = 0.0009). The PPF was significantly larger in VPs from the RCA (0.92 ± 0.48 mm3 vs. 0. 57± 0.34 mm3, p = 0.0041) compared to VPs located in the LCA. No differences were found regarding the total epicardial fat between the two groups (p = 0.386).

Conclusions

Atherosclerotic plaques located in the RCA exhibited a higher number of vulnerability characteristics compared to those located in the left coronary system and PPF was more pronounced in the regions surrounding VPs located within the RCA. This difference in vulnerability features could be explained not only by geometrical and hemodynamical characteristics of the coronary circulation, but also by inflammation-mediated alteration of endothelial shear stress triggered by release of inflammatory mediators from the local epicardial fat.

Association between varicose veins anatomical pattern and procedural complications following endovascular laser photothermolysis for chronic venous insufficiency

We sought to assess clinical characteristics and pattern of collateral network involvement associated with development of truncal (systematized) versus diffuse/non-truncal (non-systematized) varicose veins (VVs) in patients undergoing endovascular laser photothermolysis for chronic venous insufficiency (CVI). Secondly, we aimed to assess whether the type of VVs influenced the procedural complications of endovascular laser therapy. A total of 508 patients with hydrostatic VVs of the lower limbs who underwent endovenous laser treatment were included, out of which 84.1% (n=427) had truncal VVs (group 1) and 15.9% (n=81) had diffuse (non-systematized) VVs (group 2). Patients with truncal varices were significantly older (47.50±12.80 vs 43.15±11.75 years, P=0.004) and those with associated connective tissue disorders were more prone to present diffuse VVs (P=0.004). Patients in group 1 presented a significantly higher number of Cockett 1 (P=0.0017), Cockett 2 (P=0.0137), Sherman (P<0.0001), and Hunter (P=0.0011) perforator veins compared to group 2, who presented a higher incidence of Kosinski perforators (P<0.0001). There were no significant differences regarding postoperative complications: thrombophlebitis (P=0.773), local inflammation (P=0.471), pain (P=0.243), paresthesia (P=1.000), or burning sensation (P=0.632). Patients with more advanced CEAP (clinical, etiologic, anatomic, pathophysiologic) classes were older (P<0.0001), more were males (39.05 vs 27.77%, P=0.0084), more were prone to present ulcers (P<0.0001) and local hyperthermia (P=0.019), and presented for endovenous phlebectomy after a longer time from symptom onset. In patients with CVI, systematized VVs were associated with a more severe clinical status and a distinct anatomical pattern of perforators network compared to non-systematized VVs, which is more common in advanced stages.

Sequence analysis of 16S rRNA, gyrB and catA genes and DNA-DNA hybridization reveal that Rhodococcus jialingiae is a later synonym of Rhodococcus qingshengii

The results of 16S rRNA, gyrB and catA gene sequence comparisons and reasserted DNA-DNA hybridization unambiguously proved that Rhodococcus jialingiae Wang et al. 2010 and Rhodococcus qingshengii Xu et al. 2007 represent a single species. On the basis of priority R. jialingiae must be considered a later synonym of R. qingshengii.

Total body replacement with iliac bone graft and metal plate stabilization in lower cervical spine

15 patients presented with cervical spine dislocation and kyphotic spondylosis due to traumatic fracture and vertebral body tumour underwent surgical decompression and fixation via the anterior approach in one stage. Decompression was achieved by resection of the body of the vertebra while fixation meant implantation of iliac bone graft with metal plate fixation. Early reduction of the dislocation was impossible or insufficient in most of the cases. Therefore the majority of operations were "late decompression". Patients with root or partial cord lesions had the most significant improvement. In some selected cases, however, who suffered from a total cord lesion due to C6 or C7 fracture-dislocation, surgical decompression of the C7 and/or C8 roots by resection of the C6 or C7 vertebral bodies could lead to useful motor improvement in the hands and the fingers.