Diagonal Bifurcation Research Articles

Abstract 10178: Concurrent Left Ventricular and Left Anterior Coronary Artery Thrombus; Is Covid-19 an Innocent Bystander?

Case presentation: A 36-year-old male was admitted to a local hospital with respiratory failure secondary to COVID-19 pneumonia. Initial management included oxygen, dexamethasone and baricitinib. On day 14 of illness the patient developed severe chest pain associated with widespread dynamic ST segment elevation and an elevated high sensitivity troponin I (17516 ng/L). He was transferred to a tertiary center for cardiac evaluation. Cardiovascular risk factors included treated hypertension and obesity (BMI 34). Physical exam revealed a blood pressure of 145/95 mmHg, regular heart rate at 90 bpm and coarse crepitations in bilateral lower lungs with a 3L oxygen requirement. Differentials included myopericarditis however, clinical suspicion for an acute coronary syndrome remained high. Urgent coronary angiogram revealed a large filling defect (figure 1A) at the mid-vessel of the LAD at the 1st diagonal bifurcation, likely a thrombus. Dual antiplatelet therapy, heparin and tirofiban infusion were commenced. Furthermore, echocardiography performed the same day revealed a reduced LVEF secondary to LAD territory hypokinesis and an associated apical left ventricular thrombus measuring 2.2x1.3 cm (figure 1B). Once established on anticoagulation the patient experienced no further chest pain and was discharged home on warfarin.The left ventricular thrombus was monitored for resolution in the community with serial transthoracic echocardiograms. Discussion: Raised highly sensitive troponin in the vicinity of severe COVID-19 infection is common, however, when associated with chest pain and or dynamic ECG changes myocarditis must be considered. The cytokine storm triggered by a SARS-CoV-2 infection can be thrombogenic, resulting from increased platelet activation and decreased fibrinolysis. This process may further complicate the evaluation and acute coronary syndrome does need consideration, even in those patients at a younger age with minimal risk factors.

Practical use of dual-lumen catheter-facilitated reverse wire technique for nonhighly angulated side branch

Dual-lumen catheter (DLC)-facilitated reverse wire technique is considered a method of last resort for inserting a guidewire into a markedly angulated side branch. Moreover, this technique can be practically applied to other types of anatomical variations around the bifurcation. Case 1 was that of a 53-year-old man with a tight stenosis of the proximal left anterior descending artery at the diagonal bifurcation with angiographically apparent coronary dissection. We successfully achieved guidewire insertion into the targeted branch using the DLC-facilitated reverse wire technique. Case 2 involved a 78-year-old man with total occlusion of the mid-portion of the right coronary artery. The guidewire reentry point in the atrioventricular branch was slightly distant from the true distal end of the occlusion. We successfully used the DLC-facilitated reverse wire technique to pass a second guidewire to the posterodescending artery. Case 3 was that of an 80-year-old man whose coronary artery had an aneurysm with severe stenoses at both entry and exit of the aneurysm. We adopted the DLC-facilitated reverse wire technique and easily advanced the guidewire by matching the guidewire advancing path with the direction of the sequential conduit constituted by the coronary aneurysm and stenosis. The timing of decision-making to try the DLC-facilitated reverse wire technique is important. The lesion for which reverse wiring is suitable is usually difficult to be treated with conventional guidewire crossing. We have to promptly judge the validity of applying this technique based on the angiographic findings of targeted lesions and take immediate action to implement this procedure to reduce the procedural time and irradiation dose.

TCTAP C-042 LAD – Diagonal Bifurcation PCI by Mini Crush Technique

TCTAP C-042 LAD – Diagonal Bifurcation PCI by Mini Crush Technique

Missile Fragment Embolism of the Coronary Artery in a Patient with Coronary Artery Disease

A 51-year-old war veteran referred to us with typical chest pain and dyspnea on exertion. He had a history of hypertension from several years before, for which he had been prescribed anti-hypertensive medications. He also gave a history of missile fragment injury to his chest from the Iran-Iraq war, for which he had been hospitalized, but had received conservative medical treatment only. After admission and initial workup, echocardiography revealed mild left ventricular dysfunction with an ejection fraction of 45% and a metallic fragment at the diaphragmatic surface of the right ventricle. Coronary angiography showed significant stenosis at the LAD – Diagonal bifurcation, as well as a metallic fragment occluding the PDA branch of the right coronary artery. Coronary artery bypass surgery was performed successfully and the patient was discharged uneventfully. To the best of our knowledge, this is the first report of an embolized missile fragment to the coronary artery found incidentally in a patient undergoing surgery for coronary artery disease.

Suboptimal Bifurcation Stenting: A Case When the Check Comes Late

A 69-year-old man underwent percutaneous coronary intervention of a left anterior descending coronary artery (LAD) diagonal bifurcation lesion with 2 platinum-chromium everolimus-eluting stents with the culotte technique in September 2014. Dual-antiplatelet therapy was maintained for 1 year. In

Sudden Cardiac Arrest in a Methylene Tetrahydrofolate Reductase and Factor V Leiden Positive Patient

SESSION TITLE: Cardiovascular Disease SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Factor V Leiden (FVL) and Methylene Tetrahydrofolate Reductase (MTHFR) mutations are risk factors for venous thrombosis however; their role in arterial thrombosis and coronary artery disease still needs research. CASE PRESENTATION: 45 year old 25 pack year smoking female with history of Asthma, FVL Mutation, MTHFR mutation, hyperlipidemia, family history of premature heart disease and brain aneurysms presented to emergency room following a witnessed cardiac arrest with immediate initiation of basic life support and return of circulation 10 minutes after arrest with defibrillation 2 times. Patient had a one-week history of sore throat and ill contacts. She was intubated in the emergency room and initiated on a hypothermia protocol. EKG showed sinus rate at 95 BPM with poor R wave progression in the anterior leads. CT Chest revealed bilateral pulmonary infiltrates and was negative for pulmonary embolus. Echo showed left ventricular systolic function reduced with estimated ejection fraction 30-35%. Intravenous antibiotics initiated for presumed pneumonia and steroids for possible asthma exacerbation. Patient successfully extubated and rewarmed 2 days later with no gross neurological deficits. She then had a cardiac catheterization, which revealed double vessel disease including proximal LAD / first diagonal bifurcation stenosis and focal stenosis of the large ramus vessel. Left ventriculography showed normal LV function with EF 65% .She was referred to CT surgery and patient underwent a CABG 10 days after presentation without complication. DISCUSSION: FVL is a mutant form of coagulation factor V that makes Factor V insensitive to activated protein C.MTHFR is rate-limiting enzyme in the methyl cycle. Mutations of this gene affects homocysteine and vitamin B9 metabolism. MTHFR and FVL are both hypothesized to be associated with accelerated coronary artery disease/ thrombosis. There has been a documented increased prevalence of these mutations in several studies in patients with coronary disease compared to the general population however; no direct causative data has been established. Both mutations are also associated with increased prevalence in premature coronary heart disease. Some studies suggest Factor V Leiden is more of a risk factor for female active smoker patients like our patient. Data for effect of combination of these mutations is also lacking. This patient had family history of premature heart disease (mother and maternal uncle MI at age 39). Those family members were also positive for these mutations; this suggests research is warranted on combination of these mutations. CONCLUSIONS: Our case suggests for patients with MTHFR and Factor V Leiden mutations a high index of suspicion for coronary artery disease is required. Reference #1: Almawi WY et al , Factor V G1691A, prothrombin G20210A, and methylenetetrahydrofolate reductase [MTHFR] C677T gene polymorphism in angiographically documented coronary artery disease. J Thromb Thrombolysis. 2004 Jun DISCLOSURE: The following authors have nothing to disclose: Janine Harewood, Omar Akhter, Trisana Cox, Frances Puello, Essam Nakhla No Product/Research Disclosure Information

Refractory Cardiogenic Shock in a Young Male: Barriers to Urgent Heart Transplant

A 26-year-old male presented with chest pain and an acute anterior STEMI. His past history was notable for Crohn's disease on adalimumab, as well as metallic mitral and aortic valves following Candida parapsilosis endocarditis on presumed rheumatic valves. Angiography revealed a saddle embolus appearance at the proximal LAD/first diagonal bifurcation, treated with two drug eluting stents. He subsequently became febrile with a suspicious echodensity seen on the mitral annulus; the embolus therefore was thought either due to culture negative recurrent prosthetic endocarditis or thrombus in the setting of a subtherapeutic INR(1.6). Empiric antibiotics were given as well as heparin anticoagulation. His clinical course was turbulent, with refractory cardiogenic shock (ejection fraction 12%) dependent on multiple inotropes and intermittent dialysis. Concerns were raised regarding the severity of his Crohn's given intercurrent gastrointestinal bleeding; this along with suspected infection of a femoral pseudoaneurysm delayed initial transplant referral. After 4 weeks however he developed acutely worsening cardiogenic shock and was transferred to a transplant centre on VA-ECMO. Unfortunately despite urgent national listing, no body size and blood group matched donor could be found and he was delisted upon development of disseminated pulmonary aspergillosis in week 5 of VA-ECMO support. Soon after he suffered multiple embolic strokes and was palliated before passing away. Mortality for patients in refractory cardiogenic shock remains high despite modern supportive care. Early discussion with a transplant centre regarding suitability and barriers to transplant is essential; notably intra-cardiac infection does not preclude heart transplant consideration.

First diagonal artery wrapping the left ventricular apex: an unusual course

Figure 1: A coronary angiographic view showing 98% occlusion of the left anterior descending artery (LAD) at first diagonal bifurcation, 80% occlusion after the first diagonal branch and 70% occlusion of the proximal first diagonal artery. After diagonal bifurcation, LAD and first diagonal branch continues as two parallel vessels of approximately equal size down the anterior interventricular groove, soon the diagonal artery wraps around the apex of the left ventricle to feed the distal portion of the posterior interventricular groove.

Computer-Aided Patient-Specific Coronary Artery Graft Design Improvements Using CFD Coupled Shape Optimizer.

This study aims to (i) demonstrate the efficacy of a new surgical planning framework for complex cardiovascular reconstructions, (ii) develop a computational fluid dynamics (CFD) coupled multi-dimensional shape optimization method to aid patient-specific coronary artery by-pass graft (CABG) design and, (iii) compare the hemodynamic efficiency of the sequential CABG, i.e., raising a daughter parallel branch from the parent CABG in patient-specific 3D settings. Hemodynamic efficiency of patient-specific complete revascularization scenarios for right coronary artery (RCA), left anterior descending artery (LAD), and left circumflex artery (LCX) bypasses were investigated in comparison to the stenosis condition. Multivariate 2D constraint optimization was applied on the left internal mammary artery (LIMA) graft, which was parameterized based on actual surgical settings extracted from 2D CT slices. The objective function was set to minimize the local variation of wall shear stress (WSS) and other hemodynamic indices (energy dissipation, flow deviation angle, average WSS, and vorticity) that correlate with performance of the graft and risk of re-stenosis at the anastomosis zone. Once the optimized 2D graft shape was obtained, it was translated to 3D using an in-house “sketch-based” interactive anatomical editing tool. The final graft design was evaluated using an experimentally validated second-order non-Newtonian CFD solver incorporating resistance based outlet boundary conditions. 3D patient-specific simulations for the healthy coronary anatomy produced realistic coronary flows. All revascularization techniques restored coronary perfusions to the healthy baseline. Multi-scale evaluation of the optimized LIMA graft enabled significant wall shear stress gradient (WSSG) relief (~34%). In comparison to original LIMA graft, sequential graft also lowered the WSSG by 15% proximal to LAD and diagonal bifurcation. The proposed sketch-based surgical planning paradigm evaluated the selected coronary bypass surgery procedures based on acute hemodynamic readjustments of aorta-CA flow. This methodology may provide a rational to aid surgical decision making in time-critical, patient-specific CA bypass operations before in vivo execution.