Relevance of Motion Artifacts in Planning Computed Tomography on Outcomes After Transcatheter Aortic Valve Implantation.

Background: Motion artifacts in planning computed tomography (CT) for transcatheter aortic valve implantation (TAVI) can potentially skew measurements required for procedural planning. Whether such artifacts may affect safety or efficacy has not been studied. Methods: We conducted a retrospective analysis of 852 consecutive patients (mean age, 82 years; 47% women) undergoing TAVI-planning CT at a tertiary care center. Two independent observers divided CTs according to the presence of motion artifacts at the annulus level (Motion vs. Normal group). Endpoints included surrogate markers for inappropriate valve selection: annular rupture, valve embolization or misplacement, need for a new permanent pacemaker, paravalvular leak (PVL), postprocedural transvalvular gradient, all-cause death. Results: Forty-six (5.4%) patients presented motion artifacts on TAVI-planning CT (Motion group). These patients had more preexisting heart failure, moderate-severe mitral regurgitation, and atrial fibrillation. Interobserver variability of annular measurement (Normal vs. Motion group) did not differ for mean annular diameter but was significantly different for perimeter and area. Presence of motion artifacts on planning CT did not affect the prevalence of PVL (≥moderate PVL 0% vs. 2.5% p = 0.5), mean transvalvular gradient (6±3 mmHg vs 7±5 mmHg, p = 0.1), or the need for additional valve implantation (0% vs. 2.8%, p = 0.6). One annular rupture occurred (Normal group). Pacemaker implantation, procedural duration, hospital stay, 30-day outcomes, and all-cause mortality did not differ between the groups. Conclusions: Motion artifacts on planning CT were found in about 5% of patients. Measurements for valve selection were possible without the need for repeat CT, with mean diameter-derived annulus measurement being the most accurate. Motion artifacts were not associated with worse outcomes.

Hypoattenuated Leaflet Thickening After Implantation of the ACURATE neo or the ACURATE neo2 Transcatheter Heart Valve.

Subclinical leaflet thrombosis, identified as hypoattenuated leaflet thickening (HALT) on cardiac computed tomography scan, has been observed after transcatheter aortic valve replacement (TAVR). However, data on HALT after the implant of the supra-annular ACURATE neo/neo2 prosthesis are limited. This study aimed to determine the prevalence and risk factors for the development of HALT after TAVR with the ACURATE neo/neo2. A total of 50 patients who received the ACURATE neo/neo2 prosthesis were prospectively enrolled. Patients underwent a contrast-enhanced multidetector row cardiac computed tomography scan at before, after, and 6 months after TAVR. At the 6-month follow-up, HALT was detected in 16% (8 of 50 patients). These patients had a lower implant depth of the transcatheter heart valve (8 ± 2 mm vs 5 ± 2 mm, p = 0.001), less calcified native valve leaflets, a better expansion of the frame at the level of the left ventricular outflow tract, and were less often hypertensive. Thrombosis of the sinus of Valsalva occurred in 18% (9/50). There was no difference in the anticoagulation regimen between patients with and without thrombotic findings. In conclusion, HALT was present in 16% of patients at 6 months follow-up, patients presenting with HALT had a lower implant depth of the transcatheter heart valve, and HALT was detected in patients on oral anticoagulation therapy.

First-in-man implantation of the Tricento transcatheter heart valve for the treatment of severe tricuspid regurgitation.

Here we describe the first implantation of the novel bicavally anchored Tricento transcatheter heart valve via the transvenous transfemoral access in a 74-year-old woman with severe tricuspid regurgitation and holosystolic hepatic vein backflow. Following successful implantation, caval vein regurgitant volume was reduced leading to symptomatic and clinical improvement at three-month follow-up. The Tricento device represents a promising, novel therapeutic option for patients with severe tricuspid regurgitation who are not candidates for open heart surgery.

Impact of cardiac computed tomography of the interatrial septum before pulmonary vein isolation.

BACKGROUND: Multidetector computed tomography (MDCT) may be useful to identify patients with patent foramen ovale (PFO). The aim of this study was to analyze whether a MDCT performed before pulmonary vein isolation reliably detects a PFO that may be used for access to the left atrium. METHODS AND RESULTS: In 79 consecutive patients, who were referred for catheter ablation of symptomatic paroxysmal or persistent atrial fibrillation (AF), the presence of a PFO was explored by MDCT and transesophageal echocardiography (TEE). TEE was considered as the gold standard, and quality of TEE was good in all patients. In 16 patients (20.3%), MDCT could not be used for analysis because of artifacts, mainly because of AF. On TEE, a PFO was found in 15 (23.8%) of the 63 patients with usable MDCT. MDCT detected six PFO of which four were present on TEE. This corresponded to a sensitivity of 26.7%, a specificity of 95.8%, a negative predictive value of 80.7%, and a positive predictive value of 66.7%. The receiver operating characteristics curve of MDCT for the detection of PFO was 0.613 (95% confidence interval 0.493-0.732). CONCLUSIONS: MDCT may detect a PFO before pulmonary isolation. However, presence of AF may lead to artifacts on MDCT impeding a meaningful analysis. Furthermore, in this study sensitivity and positive predictive value of MDCT were low and therefore MDCT was not a reliable screening tool for detection of PFO.

Magnetic resonance imaging of uneven pulmonary perfusion in hypoxia in humans.

RATIONALE: Inhomogeneous hypoxic pulmonary vasoconstriction causing regional overperfusion and high capillary pressure is postulated for explaining how high pulmonary artery pressure leads to high-altitude pulmonary edema in susceptible (HAPE-S) individuals. OBJECTIVE: Because different species of animals also show inhomogeneous hypoxic pulmonary vasoconstriction, we hypothesized that inhomogeneity of lung perfusion in general increases in hypoxia, but is more pronounced in HAPE-S. For best temporal and spatial resolution, regional pulmonary perfusion was assessed by dynamic contrast-enhanced magnetic resonance imaging. METHODS: Dynamic contrast-enhanced magnetic resonance imaging and echocardiography were performed during normoxia and after 2 h of hypoxia (Fi(O2) = 0.12) in 11 HAPE-S individuals and 10 control subjects. As a measure for perfusion inhomogeneity, the coefficient of variation for two perfusion parameters (peak signal intensity, time-to-peak) was determined for the whole lung and isogravitational slices. RESULTS: There were no differences in perfusion inhomogeneity between the groups in normoxia. In hypoxia, analysis of coefficients of variation indicated a greater inhomogeneity in all subjects, which was more pronounced in HAPE-S compared with control subjects. Discrimination between HAPE-S and control subjects was best in gravity-dependent lung areas. Pulmonary artery pressure during hypoxia increased from 22 +/- 3 to 53 +/- 9 mm Hg in HAPE-S and 24 +/- 4 to 33 +/- 6 mm Hg in control subjects (mean +/- SD; p < 0.001), respectively. CONCLUSION: This study shows that hypoxic pulmonary vasoconstriction is inhomogeneous in hypoxia in humans, particularly in HAPE-S individuals where it is accompanied by a greater increase in pulmonary artery pressure compared with control subjects. These findings support the hypothesis of exaggerated and uneven hypoxic pulmonary vasoconstriction in HAPE-S individuals.

Effect of inspiratory and expiratory breathhold on pulmonary perfusion: assessment by pulmonary perfusion magnetic resonance imaging.

RATIONALE AND OBJECTIVES: The effect of breathholding on pulmonary perfusion remains largely unknown. The aim of this study was to assess the effect of inspiratory and expiratory breathhold on pulmonary perfusion using quantitative pulmonary perfusion magnetic resonance imaging (MRI). METHODS AND RESULTS: Nine healthy volunteers (median age, 28 years; range, 20-45 years) were examined with contrast-enhanced time-resolved 3-dimensional pulmonary perfusion MRI (FLASH 3D, TR/TE: 1.9/0.8 ms; flip angle: 40 degrees; GRAPPA) during end-inspiratory and expiratory breathholds. The perfusion parameters pulmonary blood flow (PBF), pulmonary blood volume (PBV), and mean transit time (MTT) were calculated using the indicator dilution theory. As a reference method, end-inspiratory and expiratory phase-contrast (PC) MRI of the pulmonary arterial blood flow (PABF) was performed. RESULTS: There was a statistically significant increase of the PBF (delta = 182 mL/100 mL/min), PBV (delta = 12 mL/100 mL), and PABF (delta = 0.5 L/min) between inspiratory and expiratory breathhold measurements (P < 0.0001). Also, the MTT was significantly shorter (delta = -0.5 sec) at expiratory breathhold (P = 0.03). Inspiratory PBF and PBV showed a moderate correlation (r = 0.72 and 0.61, P < or = 0.008) with inspiratory PABF. CONCLUSION: Pulmonary perfusion during breathhold depends on the inspiratory level. Higher perfusion is observed at expiratory breathhold.