Calcium scoring on coronary computed angiography tomography with photon-counting detector technology: Predictors of performance

INTRODUCTION

Obtaining accurate coronary artery calcium (CAC) score measurements from CCTA datasets with virtual non-iodine (VNI) algorithms would reduce acquisition time and radiation dose. We aimed to assess the agreement of VNI-derived and conventional true non-contrast (TNC)-based CAC scores and to identify the predictors of accuracy.

METHODS

CCTA datasets were acquired with either 120 or 140 ​kVp. CAC scores and volumes were calculated from TNC and VNI images in 197 consecutive patients undergoing CCTA. CAC density score, mean volume/lesion, aortic Hounsfield units and standard deviations were then measured. Finally, percentage deviation (VNI - TNC/TNC∗100) of CTA-derived CAC scores from non-enhanced scans was calculated for each patient. Predictors (including anthropometric and acquisition parameters, as well as CAC characteristics) of the degree of discrepancy were evaluated using linear regression analysis.

RESULTS

While the agreement between TNC and VNI was substantial (mean bias, 6.6; limits of agreement, 178.5/145.3), a non-negligible proportion of patients (36/197, 18.3%) were falsely reclassified as CAC score ​= ​0 on VNI. The use of higher tube voltage significantly decreased the percentage deviation relative to TNC-based values (β ​= ​-0.21 [95%CI: 0.38 to -0.03], p ​= ​0.020) and a higher CAC density score also proved to be an independent predictor of a smaller difference (β ​= ​-0.22 [95%CI: 0.37 to -0.07], p ​= ​0.006).

CONCLUSION

The performance of VNI-based calcium scoring may be improved by increased tube voltage protocols, while the accuracy may be compromised for calcified lesions of lower density. The implementation of VNI in clinical routine, however, needs to be preceded by a solution for detecting smaller lesions as well.

A new perspective to evaluate CLOSE protocol by coronary CT angiography including the evaluation of left atrial wall thickness

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This study was supported by the National Research, Development and Innovation Office of Hungary (NKFIA; NVKP_16-1-2016-0017 National Heart Program). The research was supported by the Thematic Excellence Programme (Tématerületi Kiválósági Program, 2020-4.1.1.-TKP2020) of the Ministry for Innovation and Technology in Hungary, within the framework of the Therapeutic Development and Bioimaging programmes of the Semmelweis University. The project was supported by the KH-17 Programme of the National Research, Development and Innovation Office of the Ministry of Innovation and Technology in Hungary (NKFIH). Bálint Szilveszter MD PhD was supported by the ÚNKP-20-4-II New National Excellence Program of the Ministry for Innovation and Technology from the source of the National research, Development and Innovation fund. M. Boussoussou and B. Vattay were supported by the “NTP-NFTÖ” (Nemzeti Tehetség Program, Nemzet Fiatal Tehetségeiért Ösztöndíj) program of the Ministry of Human Capacities in Hungary (EMMI) and by the EFOP-3.6.3-VEKOP-16-2017-00009.

Introduction

The CLOSE protocol is a novel contact-force guided technique for enclosing pulmonary veins in patients with atrial fibrillation (AF). We sought to determine whether left atrial (LA) wall thickness (LAWT) and pulmonary vein (PV) dimensions as assessed by coronary CT angiography (CTA) could influence the efficacy of successful first-pass isolation using the CLOSE protocol. Methods: In a single center, prospective study we enrolled 94 patients with symptomatic, drug-refractory AF who underwent pre-ablation left atrial CTA and initial radiofrequency catheter ablation between 2019.01-2020.09. The LA was divided into 11 regions when assessing LAWT. Additionally, the diameter and area of the PV orifices were obtained. First pass isolation was recorded separately for the right and left PVs. After the first-pass ablation circles were ready, additional ablations were applied in those cases where first pass isolation was not achieved, to reach complete PV isolation. Predictors of successful first pass isolation were determined using logistic regression models that included anthropometrical, echocardiographic and CTA derived parameters. Results: A total of 94 patients were included in the analysis with mean CHA2DS2-VASc score of 2.1 ± 1.5 (mean age 62.4 ± 12.6 years, 39.5% female). 61.7 % were paroxysmal, 38.3 were persistent AF patients. First-pass isolation rate was 76%, 71% and 54%, for the right PVs, left PVs and all four PVs, respectively. No difference was found regarding comorbidities and imaging parameters between those with and without first-pass isolation. LAWT (mean of all 11 regions or separately) had no effect on the procedural outcome (all p >0.05). Mean procedure times were 81.2 ± 19.3 minutes. Complete isolation of all four PVs was achieved in 100% of patients. Out of all assessed parameters, only RSPV diameter was associated with right sided successful PVI on first pass isolation (p = 0.04, OR 1.01). Conclusion: The use of CLOSE protocol in AF patients resulted in high periprocedural success rate in terms of first pass isolation, independently from the thickness of the LA wall. RSPV diameter could influence the results of first pass isolation.

The impact of left atrial strain parameters on systolic and diastolic improvement following TAVI

Introduction

Transcatheter aortic valve implantation (TAVI) can improve left ventricular (LV) mechanics and has been shown to improve long term survival. Data on the prognostic value of left atrial (LA) strain following TAVI are scarce. LA strain – a surrogate of LV filling pressure - can aid the early detection of diastolic dysfunction and correlates with the extent of fibrosis in atrial remodelling.

Purpose

In this multimodality study, we aimed to evaluate the prognostic value of LA function measured before hospital discharge following TAVI and to further elucidate its association with LV and LA reverse remodelling.

Methods

In this prospective single center study, we investigated 90 patients (mean age 78.5 years, 46.7% female) with severe, symptomatic aortic stenosis (AS) who underwent transthoracic echocardiography immediately after TAVI and 6 months later. LA and LV global longitudinal strain parameters were obtained by speckle tracking echocardiography. CT angiography (CTA) was performed for pre-TAVI planning and repeated at 6 months follow-up. LV mass values were derived from the serial CTA images. We defined LV reverse remodelling as reduction of myocardial mass quantified on CTA and as an improvement of LV global longitudinal strain (GLS). LA reverse remodelling was assessed based on the peak reservoir strain values (LAGS). The association of LA and LV global strain parameters, LA stiffness, systolic and diastolic functional parameters and LV mass based reverse remodelling were analysed using Pearson correlation coefficient and linear regression models.

Results

The mean LAGS and LVGLS values were 17.7% and 15.3% at discharge and 20.2% and 16.6% at follow-up, respectively (p=0.024, p<0.001). LA and LV strain values improved in 60.6% and 74.5% of all patients. Reduced LAGS (<20%) was found in 66.7% of all patients at baseline. LA strain at discharge correlated significantly with diastolic parameters (E wave, E/e', LAVI, all p<0.05). Atrial reverse remodelling based on LAGS change correlated with LVGLS change (p<0.01, standardized β=0.53) and LAGS at discharge (p=0.012, standardized β=−0.30).

LAGS correlated with the extent of morphological LV remodelling based on LV mass reduction (p=0.002, coeff: 0.36). Elevated LA stiffness at discharge (upper tercile) leads to substantially lower LAGS at 6 months versus patients with lower LA stiffness value (1. and 2. tercile): 16.4±10.0 vs 21.9±9.8, p=0.042.

Conclusion

Patients with reduced LAGS immediately after TAVI showed a larger extent of LV reverse remodelling during follow up. On the other hand, increased LA stiffness at discharge was consistent with irreversible LA damage as demonstrated by a lack of improvement in LA function.

Funding Acknowledgement

Type of funding sources: None.

The role of left atrial wall thickness and pulmonary vein anatomy in success of pulmonary vein isolation using the CLOSE protocol

Introduction

The CLOSE protocol is a novel contact-force guided technique for enclosing pulmonary veins in patients with atrial fibrillation (AF). Consistency and lesion contiguity are essential factors for procedural success. We sought to determine whether left atrial (LA) wall thickness (LAWT) and pulmonary vein (PV) dimensions as assessed by coronary CT angiography (CTA) could influence the efficacy of successful first-pass isolation using the CLOSE protocol.

Methods

In a single center, prospective study we enrolled 94 patients with symptomatic, drug-refractory AF who underwent pre-ablation left atrial CTA and initial radiofrequency catheter ablation between 2019.01–2020.09. The LA was divided into 11 regions when assessing LAWT. Additionally, the diameter and area of the PV orifices were obtained. First pass isolation was recorded separately for the right and left PVs. After the first pass ablation circles were ready, additional ablations were applied in those cases where first pass isolation was not achieved, to reach complete PV isolation. Predictors of successful first pass isolation were determined using logistic regression models that included anthropometrical, echocardiographic and CTA derived parameters.

Results

A total of 94 patients were included in the analysis with mean CHA2DS2-VASc score of 2.1±1.5 (mean age 62.4±12.6 years, 39.5% female). 61.7% were paroxysmal, 38.3 were persistent AF patients. Mean procedure times were 81.2±19.3 minutes.

Complete isolation of all four PVs was achieved in 100% of patients. First-pass isolation rate was 76%, 71% and 54%, for the right PVs, left PVs and all four PVs, respectively. No difference was found regarding comorbidities and imaging parameters between those with and without first pass isolation. LAWT (mean of all 11 regions or separately) had no effect on the procedural outcome (all p>0.05). Out of all assessed parameters, only RSPV diameter was associated with right sided successful PVI on first pass isolation (p=0.04, OR 1.01).

Conclusion

The use of CLOSE protocol in AF patients resulted in high periprocedural success rate in terms of first pass isolation, independently from the thickness of the LA wall. RSPV diameter could influence the results of first pass isolation.

Funding Acknowledgement

Type of funding sources: None.

Model based adaptive filter: assessment of image noise, sharpness and quality in coronary CT angiography

Funding Acknowledgements

Type of funding sources: None.

On Behalf of

Cardiovascular Imaging Research Group

Background

The effect of filtered back projection (FBP) and adaptive statistical iterative reconstruction (ASIR) on coronary CT angiography (CCTA) images have been extensively studied and such algorithms are ubiquitously applied in the reconstruction of CCTA datasets. Currently, however, no data is available on the impact of a recently developed model based adaptive filter (MBAF).

Purpose

 Our aim was to determine the effect of MBAF on the image quality of prospectively gated CCTA datasets.

Methods

 We evaluated the images of 102 consecutive patients who underwent clinically indicated CCTA at our department. Four reconstructions of coronary cross-sectional images (FBP, ASIR, MBAF, ASIR + MBAF) were co-registered and assessed for qualitative (graininess, sharpness, overall image quality) and quantitative [image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR)] image quality parameters. Image noise and signal were measured in the aortic root and the left main coronary artery, respectively. Graininess, sharpness, and overall image quality was assessed on a 5-point Likert scale by two experienced readers blinded to the reconstruction algorithm.

Results

 No difference in sharpness was observed amongst the reconstructions (p = 0.08). Although ASIR + MBAF was non-superior to ASIR regarding overall image quality (p = 0.99), it performed better than FBP (p < 0.001), and MBAF (p < 0.001) alone. As compared to FBP, ASIR, and MBAF, the combination of ASIR and MBAF resulted in reduced image noise [53 ± 12, 31 ± 9, 36 ± 4, and 26 ± 4 Hounsfield units (HU), respectively; p < 0.001] and improved SNR (8 ± 3, 14 ± 4, 12 ± 2,16 ± 3 HU, respectively; p < 0.001) and CNR (17 ± 3, 16 ± 4, 13 ± 2, 18 ± 4 HU, respectively; p < 0.001).

Conclusion

The combination of ASIR and MBAF resulted in reduced image noise and improved SNR and CNR. The implementation of MBAF in clinical practice may result in easier interpretation of CCTA images and could potentiate radiation dose reduction.

Orientation of the right superior pulmonary vein affects outcome after pulmonary vein isolation

Funding Acknowledgements

Type of funding sources: None.

Aims

Controversial results have been published regarding the influence of pulmonary vein (PV) anatomical variations on outcomes after pulmonary vein isolation (PVI). However, no data is available on the impact of PV orientation on the long-term success rates of point-by-point PVI. We sought to determine the impact of PV anatomy and orientation on atrial fibrillation (AF)-free survival in patients undergoing PVI using the radiofrequency point-by-point technique.

Methods and results

We retrospectively included 448 patients who underwent initial point-by-point radiofrequency ablation for AF at our department. Left atrial CT-angiography (CTA) was performed before each procedure. PV anatomical variations, ostial parameters (area, effective diameter and eccentricity), orientation and their associations with 24-month AF-free survival were analyzed. PV anatomical variations and ostial parameters were not predictive for AF-free survival (all p > 0.05). Univariate analysis showed that female sex (p = 0.025) was associated with higher rates of AF recurrence, ventral-caudal (p = 0.002), dorsal-cranial (p = 0.034) and dorsal-caudal (p = 0.042) orientation of the right superior PV (RSPV), on the other hand, showed an association with lower rates of AF recurrence, as compared to the reference ventral-cranial orientation. On multivariate analysis, both female sex [odds ratio(OR) 1.83, 95% CI 1.15-2.93, p = 0.011] and ventral-caudal RSPV orientation, compared with ventral-cranial orientation, proved to be independent predictors of 24-month AF recurrence (OR 0.37, 95% CI 0.19-0.71, p = 0.003).

Conclusion

  Female sex and ventral-caudal RSPV orientation have an impact on long-term arrhythmia-free survival. Assessment of PV orientation may be a useful tool in predicting AF-free survival and may contribute to a more personalized management of AF.

The association between early vascular aging and cyclothymic affective temperament

Funding Acknowledgements

Type of funding sources: None.

onbehalf

Cardiovascular Imaging Research Group

Background

Affective temperaments (depressive, anxious, irritable, hyperthymic, cyclothymic) are regarded as the biologically stable core of personality, and accumulating data implies their relationship with cardiovascular diseases. There are currently limited data on the association of affective temperaments and early vascular aging.

Purpose

The aim of our study was to assess the potential relationship of affective temperaments and vascular age, as assessed by coronary CT.

Methods

In our current cross-sectional study, 209 patients referred to coronary computed tomography angiography (CCTA) due to suspected coronary artery disease (CAD), were included. After the evaluation of medical history and demographic parameters, all patients completed the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Autoquestionnaire (TEMPS-A) and the Beck Depression Inventory (BDI). Vascular age was estimated using coronary artery calcium (CAC) score and we calculated its difference from chronological age for each patient. Linear regression analysis was applied to identify predictors of early vascular aging in the entire cohort and in male and female sub-populations, separately.

Results

The independent predictors of early vascular aging were female sex (B = -10.82 [95%CI: -15.30 – -6.33]), diabetes mellitus (B = 7.16 [95%CI: 1.20 – 13.12]) and dyslipidemia (B = -8.28 [95%CI: 3.94 – 12.62]). Further assessing gender differences, cyclothymic temperament score proved to be an independent predictor of early vascular aging in women (B = 0.89 [95%CI: 0.04 – 1.75]), while this association was absent in men.

Conclusion

Our results suggest that cyclothymic affective temperament contribute to early vascular aging in women.