What is the workup algorithm for a sudden increase in mechanical Aortic Valve Replacement (AVR) gradients on echocardiogram (echo)?

From the Guidelines

When a sudden increase in mechanical aortic valve replacement (AVR) gradients is detected on echocardiography, a systematic workup should be initiated immediately to rule out life-threatening complications. First, confirm the finding with a comprehensive echocardiogram, including Doppler measurements from multiple windows to rule out technical errors, as recommended by the European Association of Cardiovascular Imaging 1. Next, evaluate for patient-prosthesis mismatch by comparing current measurements with baseline post-operative values. Assess for valve thrombosis with transesophageal echocardiography (TEE), which provides superior visualization of leaflet mobility, thrombus, and pannus formation, and is a crucial step in the workup of increased gradients, as emphasized in the Valve Academic Research Consortium 3 guidelines 1. Consider cardiac CT as a complementary imaging modality, particularly for detecting pannus or leaflet calcification. Laboratory tests should include INR levels in patients on warfarin to assess anticoagulation adequacy, inflammatory markers, and blood cultures if endocarditis is suspected. Hemodynamic assessment with cardiac catheterization may be necessary in unclear cases. Management depends on the underlying cause: for thrombosis, intensified anticoagulation or thrombolysis may be appropriate; for pannus formation or structural valve deterioration, surgical intervention is typically required; for endocarditis, appropriate antibiotics and possible surgical intervention are indicated, as outlined in the 2020 ACC/AHA guideline for the management of patients with valvular heart disease 1. This systematic approach is crucial because elevated gradients may indicate potentially life-threatening complications requiring prompt intervention, and early diagnosis significantly improves outcomes. Some key considerations in the workup and management of increased mechanical AVR gradients include:

• The Valve Academic Research Consortium 3 guidelines provide a framework for assessing hemodynamic changes and valve deterioration 1
• The European Association of Cardiovascular Imaging recommends a comprehensive echocardiogram, including Doppler measurements, to assess valve function and detect potential complications 1
• The 2020 ACC/AHA guideline for the management of patients with valvular heart disease provides guidance on the management of valve-related complications, including thrombosis, endocarditis, and structural valve deterioration 1
• Cardiac CT and TEE are valuable imaging modalities for detecting pannus, leaflet calcification, and other complications 1
• Laboratory tests, including INR levels and blood cultures, are essential for assessing anticoagulation adequacy and detecting potential infections 1
• Hemodynamic assessment with cardiac catheterization may be necessary in unclear cases to guide management decisions 1.

From the Research

Workup Algorithm for Sudden Increase in Mechanical AVR Gradients on Echo

• The workup algorithm for a sudden increase in mechanical aortic valve replacement (AVR) gradients on echocardiography involves several steps, including:
  • Evaluating the patient's clinical presentation and medical history 2
  • Assessing the echocardiographic findings, including Doppler echocardiographic values for mechanical and biologic aortic valves 3
  • Considering the use of transesophageal echocardiography (TEE) to guide valve-in-valve transcatheter aortic valve replacement (ViV TAVR) in cases of failed aortic prosthesis 4
  • Comparing transthoracic and transesophageal echocardiography for TAVR sizing in high-risk patients 5
  • Evaluating the incidence of paravalvular regurgitation (PVR) after TAVR using transthoracic versus transesophageal echocardiographic guidance 6

Echocardiographic Evaluation

• Doppler echocardiographic findings for mechanical and biologic aortic valves can help identify abnormalities in valve function 3
• Transthoracic echocardiography (TTE) and TEE are both suitable methods for preprocedural aortic annulus size evaluation in preparation of TAVR procedures 5
• TEE can provide valuable guidance during ViV TAVR procedures, especially in cases of stentless bioprosthetic aortic valves 4

Clinical Considerations

• The clinical presentation and medical history of the patient should be carefully evaluated to determine the cause of the sudden increase in mechanical AVR gradients 2
• The incidence of PVR after TAVR can be influenced by various factors, including valve type and implantation technique 6
• The use of TTE or TEE guidance during TAVR procedures can impact the incidence of PVR-related events 6