Automatic Aortic Valve Cusps Segmentation from CT Images Based on the Cascading Multiple Deep Neural Networks

Accurate morphological information on aortic valve cusps is critical in treatment planning. Image segmentation is necessary to acquire this information, but manual segmentation is tedious and time consuming. In this paper, we propose a fully automatic aortic valve cusps segmentation method from CT images by combining two deep neural networks, spatial configuration-Net for detecting anatomical landmarks and U-Net for segmentation of aortic valve components. A total of 258 CT volumes of end systolic and end diastolic phases, which include cases with and without severe calcifications, were collected and manually annotated for each aortic valve component. The collected CT volumes were split 6:2:2 for the training, validation and test steps, and our method was evaluated by five-fold cross validation. The segmentation was successful for all CT volumes with 69.26 s as mean processing time. For the segmentation results of the aortic root, the right-coronary cusp, the left-coronary cusp and the non-coronary cusp, mean Dice Coefficient were 0.95, 0.70, 0.69, and 0.67, respectively. There were strong correlations between measurement values automatically calculated based on the annotations and those based on the segmentation results. The results suggest that our method can be used to automatically obtain measurement values for aortic valve morphology.

Preoperative Computed Tomography Angiography Reveals Leaflet-Specific Calcification and Excursion Patterns in Aortic Stenosis

Background: Computed tomography–based evaluation of aortic stenosis (AS) by calcium scoring does not consider interleaflet differences in leaflet characteristics. Here, we sought to examine the functional implications of these differences. Methods: We retrospectively reviewed the computed tomography angiograms of 200 male patients with degenerative calcific AS undergoing transcatheter aortic valve replacement and 20 male patients with normal aortic valves. We compared the computed tomography angiography (CTA)-derived aortic valve leaflet calcification load (AVLC CTA ), appearance, and systolic leaflet excursion (LE sys ) of individual leaflets. We performed computer simulations of normal valves to investigate how interleaflet differences in LE sys affect aortic valve area. We used linear regression to identify predictors of leaflet-specific calcification in patients with AS. Results: In patients with AS, the noncoronary cusp (NCC) carried the greatest AVLC CTA (365.9 [237.3–595.4] Agatston unit), compared to the left coronary cusp (LCC, 278.5 [169.2–478.8] Agatston unit) and the right coronary cusp (RCC, 240.6 [137.3–439.0] Agatston unit; both P <0.001). However, LCC conferred the least LE sys (42.8º [38.8º–49.0º]) compared to NCC (44.8º [41.1º–49.78º], P =0.001) and RCC (47.7º [42.0º–52.3º], P <0.001) and was more often characterized as predominantly thickened (23.5%) compared to NCC (12.5%) and RCC (16.5%). Computer simulations of normal valves revealed greater reductions in aortic valve area following closures of NCC (−32.2 [−38.4 to −25.8]%) and RCC (−35.7 [−40.2 to −32.9]%) than LCC (−24.5 [−28.5 to −18.3]%; both P <0.001). By linear regression, the AVLC CTA of NCC and RCC, but not LCC, predicted LE sys (both P <0.001) in patients with AS. Both ostial occlusion and ostial height of the right coronary artery predicted AVLC CTA, RCC ( P =0.005 and P =0.001). Conclusions: In male patients, the AVLC CTA of NCC and RCC contribute more to AS than that of LCC. LCC’s propensity for noncalcific leaflet thickening and worse LE sys , however, should not be underestimated when using calcium scores to assess AS severity.

Mural Endocarditis and Embolic Pneumonia Due to Trueperella pyogenes in an Adult Cow with Ventricular Septal Defect

Bacterial endocarditis represents one of the most frequently acquired cardiac diseases in adult cattle. Congenital heart diseases as a ventricular septal defect can facilitate bacterial endocarditis as a consequence of turbulent blood flow through the defect, causing damage to the endocardium. We describe a case of mural endocarditis associated with a ventricular septal defect in an eight-year-old female Holstein Friesian cow. The cow’s history revealed that she had presented dysorexia and a sudden decrease of milk production in the last 10 days prior to the examination. On clinical examination, jugular pulses, tachycardia with irregular heart rate and tachypnea with harsh bronchovesicular sounds were evident. Electrocardiographic examination allowed the diagnosis of an atrial fibrillation with high ventricular response rate. Transthoracic echocardiography revealed a large vegetation originating from the endocardium between the tricuspid and pulmonic valves in the right ventricle outflow. On post-mortem examination, a small muscular septal defect under the right coronary cusp of the aortic valve and a mural vegetative endocarditis were found. An abscess in the chondro-costal junction of the third right rib and metastatic pneumonia were also observed. This case report describes a rare consequence of a small ventricular septal defect that had not been previously diagnosed in an adult cow.

A CT-based technique to predict optimal projection for self-expanding TAVI in patients with different aortic valve anatomies

Background Optimal projection is essential for valve deployment during transcatheter aortic valve implantation (TAVI). The purpose of this study was to propose an approach to predict optimal projection in TAVI candidates with different aortic valve anatomies. Methods 331 patients undergoing self-expanding TAVI were included and the so-called non-coronary cusp (NCC)-parallel technique was utilized, which generated the predicted projection by connecting NCC commissures on the transverse plane on the pre-procedural computed tomography images. Results 37.8% of the study cohort were bicuspid aortic valve (BAV) patients. Around 80% of both NCC-parallel views and final views were in the right anterior oblique (RAO) and caudal (CAU) quadrant. There was less than 5° change required from the NCC-parallel view to the final implanted view in 79% of tricuspid aortic valve (TAV) patients but only in 27% (13/48) of type 0 BAV patients with coronary arteries originated from the different cusps. After excluding the above mentioned BAV patients, 62.3% (48/77) of BAV patients needed less than 5° change to achieve optimal projection and only in 8 patients, the angular change was larger than 10° in either left/right anterior oblique or cranial/caudal direction. Conclusions The NCC-parallel technique provides reliable prediction for optimal projection in self-expanding TAVI in all TAV and most BAV patients, with a vast majority of views in the RAO and CAU quadrant.

An Unusual Femoral Sheath Severing with Successful Recapture: A Case Report

This study presents a case of a successful severed femoral sheath recapture during transfemoral transcatheter aortic valve replacement (TAVR). During skin tunneling with a scalpel, the discontinuity of the femoral sheath occurred. Grasping of the distal sheath with the surgical hemostat was attempted unsuccessfully. A proximal part of the severed sheath was removed and Medtronic Sentrant introducer sheath (14 French) was then placed over the existing Confida wire which permanently remained in position, followed by the introduction of the Amplatz Left 2 (AL2) catheter which pushed the severed sheath in the ascending aorta over the Confida wire. The crucial maneuver was the entanglement of the severed sheath in the aortic non-coronary cusp which allowed for its entrapment by the AL2 catheter. This allowed for the coronary guidewire BMW Universal (0.014”) placement and a slow balloon retrieval (SeQuent NEO 2.5 x 25 mm) of the severed sheath into the introducer sheath. The guidewire/balloon catheter was then exchanged for the support wire (0.035”) followed by the removal of the introducer sheath, AL2 catheter and the severed sheath. In conclusion, sheath severing is a complex accidental event during TAVR, which can be solved by intra-aortic recapture and retraction.

A Rare Reason of Cardiogenic Shock and Acute Myocardial Infarction: Aortic Valve Myxoma

Aortic valve myxoma is a rare benign cardiac neoplasm. The association of aortic valve myxoma with cardiogenic shock and acute myocardial infarction has been reported in few observations. We report the case of a 19-year-old male patient, who underwent chest pain for two weeks, then further examinations indicated a soft spherical mass on the left coronary cusp. The patient had sporadic cardiogenic shock and acute myocardial infarction during the preoperative preparation, and we carried out emergency effective cardiopulmonary resuscitation (CPR), followed by emergency surgical operation for aortic valve tumor. Postoperative pathology showed it was a myxoma. The patient recovered smoothly and was discharged on postoperative day 7. Cardiogenic shock and acute myocardial infarction are very nonspecific, and we should be aware that patients with cardiogenic shock and acute myocardial infarction possibly suffer from aortic valve myxoma.