Redo aortic valve replacement with a non-conventional intraoperative decision to avoid left main stem obstruction.

Redo aortic valve surgery for failure of a previously implanted valve is always challenging. In case of small-sized implanted valves, the use of a balloon-expanding Sapien-3 valve can enhance the final effective orifice area, avoid complex annulus enlargement techniques, and can reduce operative time and morbidities. We describe a case where after explanting a failed 19mm St. Jude mechanical aortic valve and further deployment of a 23mm Sapien-3 valve, the left coronary ostia was obstructed by the skirt of the transcatheter prosthesis. After careful removal of a little part of the skirt, we were able to restore the coronary flow and the patient had a favorable outcome.

The Use of BASILICA Technique to Prevent Coronary Obstruction in a TAVI-TAVI Procedure

Transcatheter aortic valve implantation (TAVI) to manage structural bioprosthetic valve deterioration has been successful in mitigating the risk of a redo cardiac surgery. However, TAVI-in-TAVI is a complex intervention, potentially associated with feared complications such as coronary artery obstruction. Coronary obstruction risk is especially high when the previously implanted prosthesis had supra-annular leaflets and/or the distance between the prosthesis and the coronary ostia is short. The BASILICA technique (bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction) was developed to prevent coronary obstruction during native or valve-in-valve interventions but has now also been considered for TAVI-in-TAVI interventions. Despite its utility, the technique requires a not so widely available toolbox. Herein, we discuss the TAVI-in-TAVI BASILICA technique and how to perform it using more widely available tools, which could spread its use.

Feasibility of coronary angiography after TAVR

Background The prevalence of coronary artery disease (CAD) is high among patients with severe aortic stenosis who undergo transcatheter aortic valve replacement (TAVR). Indications for TAVR are now expanding to younger and lower risk patients. During their lifetime, these patients will be at risk of developing CAD and it is expected an increase in coronary angiography and percutaneous coronary intervention (PCI). Aortic prosthesis, particularly if in supra-annular position, may pose important technical difficulties in coronary re-engagement after TAVR. Purpose To evaluate the feasibility to reengage the coronary ostia after TAVR, describe complications and compare technical differences between coronary procedures performed before and after TAVR. Methods Retrospective analysis of 714 patients submitted to TAVR from August 2007 to December 2019. Patients who needed coronary angiography after TAVR were selected. The primary endpoint was the rate of successful coronary ostia cannulation after TAVR, defined by the possibility to selectively cannulate and inject both coronary ostia. Secondary endpoint was complications associated with coronary catheterization after TAVR. Results Among 714 patients, 25 (3.5%) patients were submitted to a total of 28 coronary angiography after TAVR. 14 patients were male (56%), mean age 78.2±6.2 years and 9 (36%) had history of previous coronary revascularization. From the 28 coronary angiographies (balloon-expandable Edwards-Sapien n=11, 44%; self-expandable CoreValve n=10, 40%; Portico n=2, 8%; Symetis n=2, 8%), 25 (89%) met the primary endpoint. Only three was semiselective (Symetis, CoreValve Evolut R and CoreValve TAVR in TAVR), with impossibility to cannulate both coronary arteries, right coronary artery and left coronary artery, respectively. 13 (46%) patients had also indication for PCI and all were successfully performed (Edwards-Sapien n=4, 31%; CoreValve n=6, 46%; Portico n=2, 15%; Symetis n=1, 8%). The main indications for coronary angiography was chronic coronary syndrome (n=12, 43%) and acute coronary syndrome without ST segment elevation (n=7, 25%). Circumflex artery was the most frequently treated vessel (n=6), followed by left anterior descending artery (n=4), right coronary artery (n=3) and left main (n=2). There were no complications reported during or post-procedure. Comparing coronary angiographies before and after TAVR, there were no significant differences regarding arterial access site, catheter diameter, fluoroscopy time and quantity of contrast used in coronary angiography. Conclusion Although the need for coronary angiography was rare in patients after TAVR, selective diagnostic coronary angiographies were possible in 89% (25/28) and PCI was feasible in all patients in whom it was indicated, without any reported complications. Further prospective studies are needed to confirm the great feasibility of performing coronary angiography after TAVR. FUNDunding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Centro Hospitalar Vila Nova de Gaia / Espinho

High take-off of coronary arteries contributing to lethal myocardial ischemia: report of two cases

Introduction/Objective High take-off coronary arteries (HTO) are defined by coronary ostia arising above the sinotubular junction (STJ). Although asymptomatic in most individuals, there is increasing evidence that HTO is a risk factor for sudden cardiac death. Here we present two patients where HTO contributed to death. Methods/Case Report Patient A was a 52 year old morbidly obese male with atypical chest pain, new inferior ST elevations and troponinemia. Multiple coronary angiographies did not reveal any stenosis, but 3 stents were placed in the RCA due to concern for vasospasm. 3 days later the patient died. Autopsy revealed cardiac tamponade and non- atherosclerotic ischemic heart disease with remote apical LV scar and diffuse patchy interstitial fibrosis in the myocardium, which could be attributed to HTO of the RCA 0.5 cm above the STJ and early intramuscular courses of both coronaries. Multiple angiographies likely caused iatrogenic coronary injury and subsequent tamponade. Patient B was a healthy 33 year old female at 34 weeks gestation, who developed anaphylaxis during IV iron infusion for severe iron deficiency anemia. She was transferred to the OR for emergent C-section. Minutes after delivery she died. Autopsy revealed HTO, with coronary ostia being 0.4 cm and 0.7 cm above the STJ, respectively and acute angle take-off of LCA. No atherosclerosis was noted. The inability to increase myocardial perfusion through the coronary arteries during a high stress situation due to pregnancy, iron deficiency anemia and anaphylaxis likely contributed to lethal myocardial ischemia. Results (if a Case Study enter NA) NA Conclusion HTO and other coronary artery anomalies (CAAs) should be considered in cases of cryptogenic acute and chronic myocardial ischemia. Hemodynamic characterization of HTO, including those < 1 cm above the STJ in presence and absence of other CAAs may help better understand their pathophysiologic significance. Antemortem diagnosis requires high clinical suspicion and appropriate surgical intervention could be life-saving.

Giant Distal Anastomotic Pseudoaneurysm 35 Years after Bentall Operation Mimicking an “Elephant Trunk”

We present the case of a giant distal aortic pseudoaneurysm 35 years after a classic mechanical Bentall operation. Computed tomography and coronary angiography showed that this originated from the distal suture line. The proximal suture and coronary ostia appeared to be intact. At reoperation, we found a complete dehiscence of distal suture line: the graft was floating in the pseudoaneurysm, mimicking an “elephant trunk” procedure. This complication suggested a systematic and accurate follow-up of patients who underwent an original Bentall procedure.

Deep Reinforcement Learning with Explicit Spatio-Sequential Encoding Network for Coronary Ostia Identification in CT Images

Accurate identification of the coronary ostia from 3D coronary computed tomography angiography (CCTA) is a essential prerequisite step for automatically tracking and segmenting three main coronary arteries. In this paper, we propose a novel deep reinforcement learning (DRL) framework to localize the two coronary ostia from 3D CCTA. An optimal action policy is determined using a fully explicit spatial-sequential encoding policy network applying 2.5D Markovian states with three past histories. The proposed network is trained using a dueling DRL framework on the CAT08 dataset. The experiment results show that our method is more efficient and accurate than the other methods. blueFloating-point operations (FLOPs) are calculated to measure computational efficiency. The result shows that there are 2.5M FLOPs on the proposed method, which is about 10 times smaller value than 3D box-based methods. In terms of accuracy, the proposed method shows that 2.22 ± 1.12 mm and 1.94 ± 0.83 errors on the left and right coronary ostia, respectively. The proposed method can be applied to the tasks to identify other target objects by changing the target locations in the ground truth data. Further, the proposed method can be utilized as a pre-processing method for coronary artery tracking methods.

Some Anatomical Variations of the Coronary Circulation among Sri Lankan Adults

The coronary circulation has been the centre of focus of many anatomists, pathologists, cardiologists, cardiothoracic surgeons, physiologists and even the general public especially since the introduction of coronary angiography during the 1960's. Though a large number of data regarding the coronary circulation of the Western populations are available, research about coronary circulation of the Sri Lankan population is comparatively rare. This study comprises of data from 150 autopsy specimens of adult Sri Lankans died due to non-cardiac causes. 99.3% had a tricuspid aortic valve while only in 0.7% the aortic valve was bi-cuspid. The incidence of the ectopic origin of the left and the right coronary artery was equal (1.3%), and the posterior sinus was devoid of coronary ostia. A 55.3% of the study population had a single coronary artery ostium for each main coronary artery. The corresponding figure for the left coronary artery was 91.3%. Six percent (06%) of the right coronary ostia were positioned significantly above the sinus while the corresponding figure for the left coronary ostia was higher (17.5%). The average left ventricular wall thickness for males and females were 13mm and 12mm respectively. Significant muscular bridging (in relation to at-least one coronary artery) was found in 19.3% of the study population. The study concludes that variations in the cardiac anatomy are commoner than expected. As per Kitzman chart, cardiac dimensions of the Sri Lankans are somewhat smaller compared to the dimensions of the Western populations.