From the Guidelines
Tricuspid inflow peak diastolic gradient is a key indicator for tricuspid valve stenosis, with a mean pressure gradient >5 to 10 mm Hg at a heart rate of 70 bpm suggesting severe stenosis. This measurement is crucial in assessing the hemodynamic significance of tricuspid valve disease and guiding treatment decisions. The transtricuspid diastolic gradient is highly variable and can be affected by heart rate, forward flow, and phases of the respiratory cycle 1.
Some key points to consider when interpreting tricuspid inflow peak diastolic gradient include:
- A mean pressure gradient >5 to 10 mm Hg at a heart rate of 70 bpm is indicative of severe tricuspid stenosis 1
- The normal mean transtricuspid gradient is often < 6 to 9 mmHg, depending on the prosthesis type 1
- An early tricuspid peak velocity ≥ 1.9–2 m/s and a mean transtricuspid pressure gradient ≥ 6–9 mmHg are suggestive of possible tricuspid prosthetic obstruction 1
- Velocities can vary with respiration, heart rate, chamber compliances and pressures, and the presence of any obstruction, making it essential to average a minimum of 5 cycles during end-expiratory or quiet respiration 1
In clinical practice, a tricuspid inflow peak diastolic gradient above 5 mmHg should prompt further evaluation for tricuspid valve stenosis, including echocardiography and potentially other imaging modalities. The severity of tricuspid stenosis can be determined by the pressure gradient, with higher gradients indicating more severe stenosis. Treatment decisions, including whether valve intervention is necessary, can be guided by the severity of the stenosis and the presence of symptoms such as fatigue, peripheral edema, and signs of right heart failure.
From the Research
Tricuspid Inflow Peak Diastolic Gradient
The tricuspid inflow peak diastolic gradient is an indicator of:
- Tricuspid stenosis severity, with higher gradients indicating more severe stenosis 2
- Tricuspid valve function, with abnormal gradients suggesting valve dysfunction 3, 4
- Potential overestimation of pressure gradients by echocardiography in patients with tricuspid regurgitation 5
Key Findings
- The Doppler-derived tricuspid mean diastolic gradient correlates moderately well with the catheterization-determined mean diastolic gradient 2
- The tricuspid valve area calculated by Doppler echocardiography correlates well with the catheterization-determined tricuspid valve area 2
- Tricuspid regurgitation severity can influence the accuracy of echocardiographic peak systolic transtricuspid pressure gradient measurements 5
- Three-dimensional echocardiography can provide a more accurate and efficient evaluation of the tricuspid valve compared to two-dimensional echocardiography 6
Clinical Implications
- The tricuspid inflow peak diastolic gradient should be interpreted in the clinical context, taking into account the presence of tricuspid regurgitation and other valve diseases 5, 3
- Threshold values for normal tricuspid mechanical valve function have been established, which can be used to identify dysfunctional prostheses 4