Aortic root thrombus complicated by left main coronary artery occlusion visualized by 3D echocardiography in a patient with continuous-flow left ventricular assist device

Aortic Thrombosis in Patients on Mechanical Circulatory Support: A Systematic Literature Review

BACKGROUND

Aortic valve (AV) thrombosis is an uncommon but ominous complication in patients managed with mechanical circulatory support (MCS) devices. In this systematic review, we summarised the data on clinical presentations and outcomes in such patients.

METHODS

We searched articles on PubMed and Google Scholar, reporting at least one adult patient with aortic thrombosis on MCS support and where the individual patient data could be extracted. We grouped the patients by the type of MCS (temporary or durable), and the type of the AV (prosthetic, surgically modified, or native) RESULTS: We identified reports on six patients with aortic thrombus on short-term MCS, and on 41 patients on durable left ventricular assist devices (LVADs). On temporary MCS, AV thrombus typically causes no symptoms and is found incidentally pre- or intra-operatively. For those with durable MCS, the occurrence of aortic thrombus forming on prosthetic or surgically modified valves appears to be more related to the intervention on the valve, rather than from the presence of LVAD. The mortality in this group was 18%. In patients with native AV on durable LVAD support, 60% of patients presented with acute myocardial infarction, acute stroke, or acute heart failure, and mortality in this cohort was 45%. In terms of management, heart transplantation was most successful.

CONCLUSIONS

While the outcomes of aortic thrombosis were good in patients where temporary MCS was used in the setting of aortic valve surgery, patients with native AV who develop this complication on durable LVAD have high morbidity and mortality. Cardiac transplantation should be strongly considered in eligible candidates because other therapies provide inconsistent results.

Aortic root thrombosis leading to STEMI in a Heartmate 3 patient

Despite left ventricular assist device (LVAD) therapy becoming established for end-stage heart failure (HF), complications remain. Thromboembolic complications are rare with the newest iteration of LVADs. We managed a case of a continuous-flow LVAD-related thromboembolic event that presented as an acute myocardial infarction. A 64-year-old male who underwent Heartmate III^® LVAD implantation had crushing substernal chest pain and ventricular tachycardia with acute anterolateral myocardial infarction on electrocardiogram on post-operative day 9. Echocardiography showed closed aortic valve and mild aortic regurgitation, but CT angiography showed thrombus within the left coronary cusp despite full anticoagulation. Continuous suction of blood from the left ventricle despite pulsatile flow into the ascending aorta resulted in a minimally opening aortic valve and stagnation of blood leading to thrombosis on the coronary cusp. Apart from post-operative ventricular tachycardia and right ventricular failure, he had adequate body size (body surface area 2.13 m²) and no post-operative or coagulopathy which could predispose him to thrombosis. Coronary angiography revealed stable severe three-vessel disease and thrombus in left main and proximal circumflex artery, and he had aspiration thrombectomy, and international normalized ratio target was increased to 3-3.5 with aspirin 325 mg daily. He survived to discharge but died 60 days after LVAD implant with multiple low flow alarms, and cardiac arrest. We review the literature and propose a management algorithm for patients with impaired AV opening and aortic root thrombosis.

Case Report: Two Cases of Watershed Phenomenon in Mechanical Circulatory Support Devices: Computed Tomography Angiography Imaging and Literature Review

Mechanical circulatory support (MCS) has become a processing technique used in end-stage heart failure (ESHF) because it can significantly improve survival and quality of life in patients with ESHF as either a transitional support therapy or a permanent replacement therapy before heart transplant. However, various potential complications associated with MCS need to be considered, especially aortic root thrombus formation. It’s critical to have an appropriate diagnosis of aortic root thrombus and “watershed” because the prognosis and treatment are different. Both “watershed” and aortic root thrombus formation can be characterized by computed tomography angiography. The CT manifestations of two patients who had MCS device implantation in our hospital (one with intra-aortic balloon pumps + extracorporeal membrane oxygenators, the other with left ventricular assist devices) were reported, and a literature review that recognized of “watershed” phenomenon in the aortic root was conducted.

HFSA/SAEM/ISHLT clinical expert consensus document on the emergency management of patients with ventricular assist devices

Mechanical circulatory support is now widely accepted as a viable long-term treatment option for patients with end-stage heart failure (HF). As the range of indications for the implantation of ventricular assist devices grows, so does the number of patients living in the community with durable support. Because of their underlying disease and comorbidities, in addition to the presence of mechanical support, these patients are at a high risk for medical urgencies and emergencies (Table 1). Thus, it is the responsibility of clinicians to understand the basics of their emergency care. This consensus document represents a collaborative effort by the Heart Failure Society of America, the Society for Academic Emergency Medicine, and the International Society for Heart and Lung Transplantation (ISHLT) to educate practicing clinicians about the emergency management of patients with ventricular assist devices. The target audience includes HF specialists and emergency medicine physicians, as well as general cardiologists and community-based providers.

An Emergency Medicine-focused Summary of the HFSA/SAEM/ISHLT Clinical Consensus Document on the Emergency Management of Patients With Ventricular Assist Devices

Mechanical circulatory support is increasingly used as a long-term treatment option for patients with end-stage heart failure. Patients with implanted ventricular assist devices are at high risk for a range of diverse medical urgencies and emergencies. Given the increasing prevalence of mechanical circulatory support devices, this expert clinical consensus document seeks to help inform emergency medicine and prehospital providers regarding the approach to acute medical and surgical conditions encountered in these complex patients.

Aortic Valve Thrombosis after Valve-Sparing Aortic Root Replacement and Insertion of an Extracorporeal Left Ventricular Assist Device, Masked by Mediastinal Packing

Aortic valve (AV) or aortic root thrombus related to a left ventricular assist device (LVAD) is a relatively uncommon but potentially life-threatening complication. In the present report, we describe a complex case where echocardiographic diagnosis of AV thrombosis was obscured by the presence of mediastinal packing in a patient who underwent valve-sparing aortic root replacement and insertion of the CentriMag™ LVAD for postcardiotomy cardiogenic shock. A large AV thrombus may develop rapidly in patients with LVADs. This case highlights the importance of a careful and thorough transesophageal echocardiography examination in detecting this complication and in altering surgical management.