TAPSE/PASP Optimization Index (Therapeutic Decision Aid)

TAPSE/PASP Optimization Index: Comprehensive Explanation and Clinical Context Definition & Formula: The TAPSE/PASP ratio (mm/mmHg) is a noninvasive surrogate of right ventricular-pulmonary arterial (RV-PA) coupling. It is calculated as tricuspid annular plane systolic excursion (TAPSE, in mm) divided by pulmonary artery systolic pressure (PASP, in mmHg). Measurement: TAPSE is measured by M-mode at the lateral tricuspid annulus in the apical 4-chamber view.

PASP is estimated from peak tricuspid regurgitation velocity (Bernoulli) plus an estimate of right atrial pressure (e.g., from IVC size/collapsibility). Interpretation: Lower ratios indicate RV-PA uncoupling. In heart failure populations, values ≤ 0.36 mm/mmHg consistently associate with worse outcomes; several cohorts identify ≤ 0.31 as a very abnormal tier.

In pulmonary arterial hypertension, very low ratios (< 0.19) identify high 1-year mortality risk, while 0.19-0.31 reflects intermediate risk. In acute pulmonary embolism, a cut-off near 0.34 has been reported for adverse outcomes. These thresholds are population-specific and should be interpreted alongside clinical context and measurement quality.

Clinical Significance: The ratio integrates RV contractile shortening (TAPSE) relative to afterload (PASP), offering a practical bedside gauge of RV reserve and treatment response. It adds prognostic value across HF (HFrEF/HFpEF), PAH, valve disease, CRT candidates, and acute PE cohorts. Limitations: Angle dependency and tethering can affect TAPSE; PASP estimation depends on adequate TR signal and RA pressure assumptions.

Consider complementary parameters (RV FAC, S′, TAPSE/sPAP via invasive data, RV strain, TR grade, IVC indices) and disease-specific risk models. References Anastasiou V, et al. Heart Failure Reviews.

2024: TAPSE/PASP ≤ 0.36 linked to mortality in HF meta-analysis. Fortuni F, et al. JACC: Cardiovascular Interventions.

2023: In PAH, TAPSE/PASP < 0.19 associated with high 1-year mortality; 0.19-0.31 intermediate. Tello K, et al. Eur Respir J.

2019: Conceptual and empirical basis for RV-PA coupling via TAPSE/PASP. Riccardi M, et al. 2024 (open-access cohort): Prognostic value in outpatients with LV systolic dysfunction.

Anatolian Journal of Cardiology, 2024: Acute PE optimal cut-off ≈ 0.34 by Youden index. Additional contemporary reviews: Yao M, et al. Diagnostics.

2025 (limitations); Gutierrez-Ortiz E, et al. J Clin Med. 2025 (TTE vs invasive agreement).