ECG signs of right ventricular hypertrophy may help distinguish pulmonary arterial hypertension and pulmonary hypertension due to left ventricular diastolic dysfunction.

Objectives: Distinguishing pulmonary arterial hypertension (PAH) and pulmonary hypertension due to left ventricular diastolic dysfunction (PHLDD) is essential for the correct disease management. We compared the importance of electrocardiographic (ECG) signs of right ventricular hypertrophy (RVH) in patients with similar degree PAH and PHLDD.
Methods: ECG analysis was retrospectively performed in 17 PHLDD and in 17 PAH patients with catheterization-confirmed moderate pulmonary hypertension. Sensitivity, specificity, and positive and negative predictive values for individual RVH signs were calculated.
Results: The PAH group showed a higher prevalence of the following: R/S ratio > 1 in V1 (p < 0.001), R in V1 + S in V6 > 1.05 mV (p < 0.01), R wave peak time > 0.035 s (p < 0.05), right ventricular strain (p < 0.001), and A+R-PL parameter (i. e. R(V1) + S1 - S(V1)) = 0.07 mV (p < 0.05). The sensitivity and negative predictive value (NPV) of RVH signs for distinguishing PAH and PHLDD were low for all signs except right ventricular strain (sensitivity 71%, NPV 77%). The specificity and positive predictive value (PPV) of all six parameters were both 100%.
Conclusions: In patients with pulmonary hypertension detected using echocardiography, ECG presence of RVH/overload may exclude LV diastolic dysfunction as a cause of PH and suggests the diagnosis of PAH (Tab. 3, Ref. 19).