Risk stratification of patients with Brugada syndrome: the impact of myocardial strain analysis using cardiac magnetic resonance feature tracking.

OBJECTIVE: This study evaluated the prognostic significance of cardiac magnetic resonance myocardial feature tracking (CMR-FT) in patients with Brugada syndrome (BrS) to detect subclinical alterations and predict major adverse events (MAE). METHODS: CMR was performed in 106 patients with BrS and 25 healthy controls. Biventricular global strain analysis was assessed using CMR-FT. Patients were followed over a median of 11.6 [8.8 ± 13.8] years. RESULTS: The study cohort was subdivided according to the presence of a spontaneous type 1 ECG (sECG) into sBrS (BrS with sECG, n = 34 (32.1%)) and diBrS (BrS with drug-induced type 1 ECG, n = 72 (67.9%)). CMR-FT revealed morphological differences between sBrS and diBrS patients with regard to right ventricular (RV) strain (circumferential (%) (sBrS -7.9 ± 2.9 vs diBrS - 9.5 ± 3.1, p = 0.02) and radial (%) (sBrS 12.0 ± 4.3 vs diBrS 15.4 ± 5.4, p = 0.004)). During follow-up, MAE occurred in 11 patients (10.4%). Multivariable analysis was performed to identify independent predictors for the occurrence of events during follow-up. The strongest predictive value was found for RV circumferential strain (OR 3.2 (95% CI 1.4 - 6.9), p = 0.02) and RVOT/BSA (OR 3.1 (95% CI 1.0 - 7.0), p = 0.03). CONCLUSIONS: Myocardial strain analysis detected early subclinical alterations, prior to apparent changes in myocardial function, in patients with BrS. While usual functional parameters were within the normal range, CMR-FT revealed pathological results in patients with an sECG. Moreover, RV circumferential strain and RVOT size provided additional prognostic information on the occurrence of MAE during follow-up, which reflects electrical vulnerability.

Additional Value of Machine-Learning Computed Tomographic Angiography-Based Fractional Flow Reserve Compared to Standard Computed Tomographic Angiography.

Background: Machine-learning-based computed-tomography-derived fractional flow reserve (CT-FFRML) obtains a hemodynamic index in coronary arteries. We examined whether it could reduce the number of invasive coronary angiographies (ICA) showing no obstructive lesions. We further compared CT-FFRML-derived measurements to clinical and CT-derived scores. Methods: We retrospectively selected 88 patients (63 ± 11years, 74% male) with chronic coronary syndrome (CCS) who underwent clinically indicated coronary computed tomography angiography (cCTA) and ICA. cCTA image data were processed with an on-site prototype CT-FFRML software. Results: CT-FFRML revealed an index of >0.80 in coronary vessels of 48 (55%) patients. This finding was corroborated in 45 (94%) patients by ICA, yet three (6%) received revascularization. In patients with an index ≤ 0.80, three (8%) of 40 were identified as false positive. A total of 48 (55%) patients could have been retained from ICA. CT-FFRML (AUC = 0.96, p ≤ 0.0001) demonstrated a higher diagnostic accuracy compared to the pretest probability or CT-derived scores and showed an excellent sensitivity (93%), specificity (94%), positive predictive value (PPV; 93%) and negative predictive value (NPV; 94%). Conclusion: CT-FFRML could be beneficial for clinical practice, as it may identify patients with CAD without hemodynamical significant stenosis, and may thus reduce the rate of ICA without necessity for coronary intervention.

Correlation of machine learning computed tomography-based fractional flow reserve with instantaneous wave free ratio to detect hemodynamically significant coronary stenosis.

BACKGROUND: Fractional flow reserve based on coronary CT angiography (CT-FFR) is gaining importance for non-invasive hemodynamic assessment of coronary artery disease (CAD). We evaluated the on-site CT-FFR with a machine learning algorithm (CT-FFRML) for the detection of hemodynamically significant coronary artery stenosis in comparison to the invasive reference standard of instantaneous wave free ratio (iFR®). METHODS: This study evaluated patients with CAD who had a clinically indicated coronary computed tomography angiography (cCTA) and underwent invasive coronary angiography (ICA) with iFR®-measurements. Standard cCTA studies were acquired with third-generation dual-source computed tomography and analyzed with on-site prototype CT-FFRML software. RESULTS: We enrolled 40 patients (73% males, mean age 67 ± 12 years) who had iFR®-measurement and CT-FFRML calculation. The mean calculation time of CT-FFRML values was 11 ± 2 min. The CT-FFRML algorithm showed, on per-patient and per-lesion level, respectively, a sensitivity of 92% (95% CI 64-99%) and 87% (95% CI 59-98%), a specificity of 96% (95% CI 81-99%) and 95% (95% CI 84-99%), a positive predictive value of 92% (95% CI 64-99%), and 87% (95% CI 59-98%), and a negative predictive value of 96% (95% CI 81-99%) and 95% (95% CI 84-99%). The area under the receiver operating characteristic curve for CT-FFRML on per-lesion level was 0.97 (95% CI 0.91-1.00). Per lesion, the Pearson's correlation between the CT-FFRML and iFR® showed a strong correlation of r = 0.82 (p < 0.0001; 95% CI 0.715-0.920). CONCLUSION: On-site CT-FFRML correlated well with the invasive reference standard of iFR® and allowed for the non-invasive detection of hemodynamically significant coronary stenosis.

Association of Serum Lipid Profile With Coronary Computed Tomographic Angiography-derived Morphologic and Functional Quantitative Plaque Markers.

PURPOSE: Recent advances in image quality of coronary computed tomographic angiography (cCTA) have enabled improved characterization of coronary plaques. Thus, we investigated the association between quantitative morphological plaque markers obtained by cCTA and serum lipid levels in patients with suspected or known coronary artery disease. MATERIALS AND METHODS: We retrospectively analyzed data of 119 statin-naive patients (55±14 y, 66% men) who underwent clinically indicated cCTA between January 2013 and February 2017. Patients were subdivided into a plaque and a no-plaque group. Quantitative and morphologic plaque markers, such as segment involvement score, segment stenosis score, remodeling index, napkin-ring sign, total plaque volume, calcified plaque volume, and noncalcified plaque volume (NCPV) and plaque composition, were analyzed using a semiautomated plaque software prototype. Total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein, low-density lipoprotein/high-density lipoprotein ratio, and triglycerides were determine in both groups. RESULTS: Higher age (61±11 y vs. 52±14 y, P<0.0001) and a higher likelihood of male gender (77% vs. 56%, P<0.0001) were observed in the plaque group. Differences in lipid levels were neither observed for differentiation between plaque presence or absence, nor after subcategorization for plaque composition. LDL serum levels >160 mg/dL correlated with higher NCPV compared with patients with LDL between 100 and 160 mg/dL (112 vs. 27 mm, P=0.037). Other markers were comparable between the different groups. CONCLUSION: Statin-naive patients with known or suspected coronary artery disease did not show differences in lipid levels related to plaque composition by cCTA. Patients with plaques tended to be men and were significantly older. High LDL levels correlated with high NCPV.

Bedside implantation of a new temporary vena cava inferior filter - Safety and efficacy results of the European ANGEL-Registry.

PURPOSE: Pulmonary embolism (PE) is a frequently occurring complication in critically ill patients. Simultaneous occurrence of PE and life-threatening bleeding, may render medical anticoagulation impossible. For these patients, inferior vena cava filters (IVCF) present a valuable therapeutic alternative. The Angel® catheter is a novel IVCF that provides temporary protection from PE and is implanted at bedside. The primary objective of the European Angel® catheter registry is to evaluate the safety and efficacy of this IVCF. MATERIAL AND METHODS: The European Angel® catheter registry is an observational, multi-centre registry. Patients from four countries and eight sites that have undergone Angel® catheter implantation between March 2013 and February 2017 were enrolled. RESULTS: A total of 114 critically ill patients were included. The main indication for implantation was a high-risk for PE in combination with contraindications for anticoagulation (69.3%). One clinically non-significant PE (0.9%) occurred in a patient with an indwelling Angel® catheter. No cases of catheter associated serious complications were observed. CONCLUSION: Data shows that the Angel® catheter is a safe and effective approach to overcome the acute phase of critically ill patients with a high risk for the development of PE or an established PE, when an anticoagulation therapy is contraindicated.

Clinical Impact of Rest Dual-energy Computed Tomography Myocardial Perfusion in Patients with Coronary Artery Disease.

BACKGROUND/AIM: To evaluate the hypothesis that patients with suspected coronary artery disease (CAD) assessed using rest dual-energy computed tomography-derived myocardial perfusion imaging (DECT-P), could have fewer invasive coronary angiographies (ICA), showing non-obstructive CAD. MATERIALS AND METHODS: Patients who had undergone coronary computed tomography angiography (cCTA), rest DECT-P and ICA were analyzed. RESULTS: We evaluated 51 patients (62.7% males, mean age 51.6±12.8 years). Rest DECT-P identified perfusion defects in three (10.7%) of the 28 patients with cCTA negative for luminal stenosis and in 10 (43.5%) of the 23 patients with cCTA positive for luminal stenosis. In total, 21 patients underwent both cCTA and ICA, of which seven (33.3%) showed obstructive CAD. Rest DECT-P revealed false-negative results in four cases (19.1%) and false-positive results in six cases (28.6%). CONCLUSION: Adding rest DECT-P to cCTA has no incremental diagnostic value over cCTA alone, to exclude haemodynamically significant CAD. Therefore, a rest-stress-DECT-P protocol or a CT-based FFR calculation might be a promising concept to improve diagnostic accuracy in a real clinical setting.