In patients with pulmonary hypertension (PH), echocardiographic pulmonary to left atrial global strain ratio accurately discriminated between pre-capillary and post-capillary PH, according to a study published in the International Journal of Cardiology.

Researchers evaluated the ability of echocardiographic pulmonary to left atrial global strain ratio to differentiate pre-capillary and post-capillary PH to see whether echocardiographic pulmonary to left atrial ratio or echocardiographic pulmonary to left atrial global strain ratio had a superior diagnostic capacity. Patients with unexplained dyspnea or heart failure who were referred for right heart catheterization were included in this study.

Transthoracic echocardiography measured left ventricular ejection fraction, wave Doppler measured max tricuspid regurgitation peak velocity, and speckle tracking echocardiography measured left atrial global strain. These measurements were used to calculate echocardiographic pulmonary to left atrial global strain ratio. Right heart catheterization was used to measure mean right atrial pressure and pulmonary artery pressure.

Of the 130 patients included in this study, 64 demonstrated pre-capillary PH, 66 demonstrated post-capillary PH, with 39 classified as isolated post-capillary PH, and 27 demonstrated combined post- and pre-capillary PH.

When analyzing the baseline characteristics, echocardiographic pulmonary to left atrial global strain ratio was lower in pre-capillary PH than post-capillary PH (0.19 vs 0.45; P =.02), and echocardiographic pulmonary to left atrial ratio was higher in pre-capillary PH compared with post-capillary PH (0.37 vs 0.20; P <.001). Echocardiographic pulmonary to left atrial global strain ratio differentiated between isolated post-capillary PH and combined post- and pre-capillary PH (0.62 vs 0.32; P =.04) and was associated with pulmonary vascular resistance (r =0.28; P =.02) and transpulmonary gradient (r =0.30; P =.01).

The diagnostic capability to distinguish pre-capillary and post-capillary PH favored echocardiographic pulmonary to left atrial global strain ratio (area under the curve [AUC] 0.80; 95% CI, 0.72-0.89; P <.001) over echocardiographic pulmonary to left atrial ratio (AUC 0.70; 95% CI, 0.61-0.80; P <.001).

Limitations of this study included a lack of standard image acquisition, the absence of a control cohort, potential errors in the variable used to calculate echocardiographic pulmonary to left atrial global strain ratio, and the inclusion of symptomatic patients in the post-capillary PH cohort.

The researchers concluded that “[t]he novel [echocardiographic pulmonary to left atrial global strain] ratio distinguishes pre-capillary from post-capillary PH and demonstrates a stronger differentiating capability as compared to [echocardiographic pulmonary to left atrial ratio].”

Reference

Venkateshvaran A, Manouras A, Kjellström B, Lund LH. The additive value of echocardiographic pulmonary to left atrial global strain ratio in the diagnosis of pulmonary hypertension [published online May 31, 2019]. Int J Cardiol. doi:10.1016/j.ijcard.2019.05.025

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This article originally appeared on The Cardiology Advisor