ECG useful in identifying pulmonary hypertension in patients with severe tricuspid regurgitation

Tricuspid valve regurgitation of moderate or high severity affects about 0.55% of the general population. TR can be classified based on the underlying mechanisms as primary, secondary or isolated TR. 

Echocardiographic evaluation of TR velocity is a critical measure in pulmonary hypertension screening. Patients are classified into a low, intermediate or high probability of pulmonary hypertension based on its value and additional features of right ventricle overload which transfers decisions of further invasive evaluation. However, in the presence of severe TR, echocardiography underestimates pulmonary artery pressure and therefore pulmonary hypertension may be left unnoticed in some patients.

Marcin Waligóra, John Paul II Hospital in Krakow, Krakow, Poland, and colleagues aimed to assess the role of electrocardiography in predicting the presence of PAH in patients with severe tricuspid regurgitation.

For this purpose, the researchers analyzed 83 consecutive patients with severe TR diagnosed between 2008 and 2021 who underwent right heart catheterization. Of them, 58 had PAH while 25 had isolated TR (iTR).

The study led to the following findings:

• Following ECG criteria supported PAH diagnosis as opposed to the diagnosis of iTR: R: SV1 > 1.0, max RV1 or 2 + max S I or aVL –SV1 > 6 mm, SI/RI > 1 in I.
• For these parameters using ROC analysis we found that the optimal thresholds suggesting the presence of pulmonary hypertension were: R: SV1 > 1.5 (AUC = 0.74, sensitivity 57.1%, specificity of 85%), max RV1 or 2 + max S I or aVL – SV1 > 3 mm (AUC = 0.76, sensitivity 91.4%, specificity of 60%) and for SI: RI > 0.71 (AUC = 0.79, sensitivity 82.5%, specificity of 70.8%).
• The presence of atrial fibrillation predicted iTR with 76% sensitivity and 81% specificity.

"The findings revealed the utility of ECG in identifying pulmonary hypertension in patients with severe TR," the researchers wrote. "The presence of atrial fibrillation facilitates iTR diagnosis, while increased values of R: SV1, R: SI, and increased max RV1 or 2 + max SI or aVL – SV1 favour the diagnosis of tricuspid regurgitation secondary to PAH."

Reference:

Waligóra, M., Smorąg, M., Bukała, N., Zygmunt, M., Kachnic, N., Lis, E., Zaczyńska, K., Wilczek, Ł., Wziątek, B., & Kopeć, G. (2023). ECG patterns to predict pulmonary arterial hypertension in patients with severe tricuspid regurgitation. Journal of Electrocardiology. https://doi.org/10.1016/j.jelectrocard.2023.11.009