Role of imaging in diagnosis and management of left ventricular assist device complications

The Role of Multimodality Imaging in Cardiomyopathy

PURPOSE OF REVIEW

There has been increasing use of multimodality imaging in the evaluation of cardiomyopathies.

RECENT FINDINGS

Echocardiography, cardiac magnetic resonance (CMR), cardiac nuclear imaging, and cardiac computed tomography (CCT) play an important role in the diagnosis, risk stratification, and management of patients with cardiomyopathies. Echocardiography is essential in the initial assessment of suspected cardiomyopathy, but a multimodality approach can improve diagnostics and management. CMR allows for accurate measurement of volumes and function, and can easily detect unique pathologic structures. In addition, contrast imaging and parametric mapping enable the characterization of tissue features such as scar, edema, infiltration, and deposition. In non-ischemic cardiomyopathies, metabolic and molecular nuclear imaging is used to diagnose rare but life-threatening conditions such amyloidosis and sarcoidosis. There is an expanding use of CCT for planning electrophysiology procedures such as cardioversion, ablations, and device placement. Furthermore, CCT can evaluate for complications associated with advanced heart failure therapies such as cardiac transplant and mechanical support devices. Innovations in multimodality cardiac imaging should lead to increased volumes and better outcomes.

Percutaneous Intervention of LVAD Outflow Graft Obstruction and Thrombosis

Left ventricular assist devices serve as a salvage therapy for patients with advanced heart failure. Complications such as thrombosis and obstruction can lead to acute device malfunction, posing significant clinical risks. A multidisciplinary approach is crucial for management. Few cases in the literature have demonstrated the safety and efficacy of percutaneous intervention, which holds significant value due to its less invasive nature and minimal risk of morbidity, especially in high-risk surgical patients.

Echocardiographic imaging and ventricular mechanics in pulsatile-flow LVAD pediatric patients: a systematic approach

Echocardiography plays a crucial role in determining the eligibility for left ventricular assist device (LVAD) placement in patients experiencing advanced heart failure (HF) and in monitoring patient care after the implantation procedure. Because of its unique nature, pediatric population and pulsatile-flow LVADs used in pediatrics require specific skills so that pediatric echocardiographers must develop a systematic approach in order to image the patients pre and post LVAD implantation. Therefore, the purpose of this narrative review is to delineate a systematic echocardiographic approach for pediatric patients supported by pulsatile-flow LVADs.

Driveline erosion of the colon as a late complication of LVAD implantation

A 69-year-old man with ischemic cardiomyopathy underwent left ventricular assist device (LVAD) implantation as destination therapy. One month after LVAD placement, the patient reported abdominal pain with driveline site purulence. Serial wound and blood cultures were positive for various Gram-positive and Gram-negative organisms. Abdominal imaging revealed a possible intracolonic course of the driveline at the splenic flexure, but there were no imaging findings suggestive of bowel perforation. A colonoscopy did not identify a perforation. The patient was treated with antibiotics but continued to experience driveline infections over the next 9 months until frank stool started draining from the driveline exit site. Our case illustrates driveline erosion of the colon causing the insidious formation of an enterocutaneous fistula and highlights a rare late complication of LVAD therapy.

Learning objective

Colonic erosion by the driveline can cause enterocutaneous fistula formation over a period of months. A change from typical infectious organisms for driveline infection should prompt investigation of a gastrointestinal source. In cases where computed tomography of the abdomen does not show perforation and there is concern for an intracolonic course of the driveline, colonoscopy or laparoscopy may be diagnostic.

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.

Laparoscopic cholecystectomy after percutaneous transhepatic gallbladder drainage for acute cholecystitis in a patient with a left ventricle assist device: A case report and brief review of the literature (with video)

For acute cholecystitis in patients with left ventricular assist devices, the use of percutaneous transhepatic gallbladder drainage to calm inflammation before planned laparoscopic cholecystectomy may be helpful in safely adjusting anticoagulation and in performing safe laparoscopic cholecystectomy, as demonstrated in this case.

Best Practices for Imaging Cardiac Device-Related Infections and Endocarditis: A JACC: Cardiovascular Imaging Expert Panel Statement

The diagnosis of cardiac device infection and, more importantly, accurate localization of the infection site, such as defibrillator pocket, pacemaker lead, along the peripheral driveline or central portion of the left ventricular assist device, prosthetic valve ring abscesses, and perivalvular extensions, remain clinically challenging. Although transthoracic and transesophageal echocardiography are the first-line imaging tests in suspected endocarditis and for assessing hemodynamic complications, recent studies suggest that cardiac computed tomography (CT) or CT angiography and functional imaging with ¹⁸F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) with CT (FDG PET/CT) may have an incremental role in technically limited or inconclusive cases on echocardiography. One of the key benefits of FDG PET/CT is in its detection of inflammatory cells early in the infection process, before morphological damages ensue. However, there are many unanswered questions in the literature. In this document, we provide consensus on best practices among the various imaging studies, which includes the detection of cardiac device infection, differentiation of infection from inflammation, image-guided patient management, and detailed recommendations on patient preparation, image acquisition, processing, interpretation, and standardized reporting.

Role of assist device implantation and heart transplantation in the long-term outcome of patients with structural heart disease after catheter ablation of ventricular tachycardia

Introduction

Ablation of ventricular tachycardias (VTs) in patients with structural heart disease (SHD) has been associated with advanced heart failure and poor survival.

Methods and results

This matched case-control study sought to assess the difference in survival after left ventricular assist device (LVAD) implantation and/or heart transplantation (HTX) in SHD patients undergoing VT ablation. From the initial cohort of 309 SHD patients undergoing VT ablation (187 ischemic cardiomyopathy, mean age 64 ± 12 years, ejection fraction of 34 ± 13%), 15 patients received an LVAD and nine patients HTX after VT ablation during a follow-up period of 44 ± 33 months.

Long-term survival after LVAD did not differ from the matched control group (p = 0.761), although the cause of lethal events was different. All post-HTX patients survived during follow-up.

Conclusion

In this matched case-control study on patients with SHD undergoing VT ablation, patients that received LVAD implantation had similar survival compared to the control group after 4‑year follow-up, while the patients with HTX had a significantly better outcome.

A case of single-incision laparoscopic surgery for acute appendicitis with left ventricular assist device

A left ventricular assist device (LVAD) is used for patients with severe heart failure. We present a case of a 35-year-old man who had undergone LVAD implantation 2 years ago for dilated phase of hypertrophic cardiomyopathy. He had right lower abdominal pain and was diagnosed with acute appendicitis. Single-incision laparoscopic surgery for appendicitis was performed. We incised approximately 3 cm of the umbilicus carefully because the driveline of LVAD was passing just caudal to the umbilicus. LVAD is only available for patients waiting for cardiac transplantation in Japan, and the number of patients with LVAD has been increasing. Adequate anticoagulant therapy is necessary because device thrombosis often causes fatal complications, but during emergency cases, the surgeons have to be cautious of bleeding and injury to the driveline of LVAD.

Aortic intervention guided by contrast-enhanced transoesophageal ultrasound whist waiting for cardiac transplantation: a case report

Background 

Aortic complications can happen during left ventricular assist devices (LVADs) insertion and its treatment remains challenging. Percutaneous aortic interventions can be an alternative to surgery in such high-risk cases.

Case summary 

We present a patient with idiopatic dilated cardiomyopathy and advanced heart failure requiring LVAD insertion as a bridge to transplant, who developed an aortic pseudoaneurysm below the anastomosis of the LVAD tube. He was successfully treated with percutaneous coiling under contrast-enhanced transoesophageal echocardiography (TOE) guidance, reaching destination therapy (heart transplantation) a year later.

Discussion 

Left ventricular assist devices provide haemodynamic support for patients with advanced heart failure waiting for heart transplantation. Although uncommon, aortic complications can happen as a result of LVAD insertion and be life-threatening. Percutaneous aortic interventions can be performed in such cases to promote thrombosis and remodelling of false lumen or aneurysmatic spaces, hence potentially reducing the risk of sudden death. Contrast-enhanced TOE can be easily and safely used to monitor the intervention in order to improve anatomic definition, guide positioning of wires and catheters and assess early results.

Cavitation in left ventricular assist device patients: a potential early sign of pump thrombosis

Mechanical ventricular support with left ventricular assist device (LVAD) has emerged as a durable and safe therapy, both as bridge-to-transplant (BTT) or destination therapy (DT), in patients with advanced heart failure (HF). However, the occurrence of pump thrombosis (PT) still represents a serious complication, especially when LVADs of first or second generation are implanted. During the latest years, some investigations have recognized the occurrence of cavitation, evidenced through transthoracic echocardiography (TTE), as a potential early and indirect sign of PT. In the present manuscript, we reviewed the available data on the occurrence of cavitation in LVAD patients as an early potential marker of PT, also presenting the hemodynamic mechanisms involved.