37-year-old-gentleman, who was presented in three occasional times to emergency department for a fast, precordial, and rhythmic symptomatic palpitations, in which the last episode was with a duration that lasted more than an hour with instability vitally that ended in performing emergency electrical cardioversion. All these episodes were symptomatic and last hospitalization was associated with pre syncopal and syncopal attacks. With evidence of Wolff-Parkinson-White syndrome the patient was brought to Electrophysiology Lab to EP study and ablation.

Background: Mean Pulmonary artery pressure (MPAP) is an indispensable hemodynamic variable for the diagnosis, classification and prognosis of Pulmonary Hypertension (PH). Its quantification is performed invasively by right heart cathererization (RHC) and non-invasively by Doppler echocardiography. Masuyama proposed its measurement by the transvalvular diastolic pulmonary gradient derived from the initial maximum velocity of pulmonary regurgitation (?PRi2) corresponding closely to the invasive measurement. Objectives: to compare 3 known echocardiographic methods to estimate MPAP and demonstrate the usefulness of the Chemla´s method in the Pulmonary Vascular Reactivity Test (PVRT). Methods: prospective, observational, double-blind study divided into two stages. A) 30 patients underwent diagnostic Doppler echocardiography in our center. Tricuspid regurgitation (TR) and pulmonary acceleration time (PAT) were measured to derive the equations: (1) 0.61xSPAP + 1.95 (Chemla) (2) Gradient mean pressure TR (?PmTR) + RAP (right atrial pressure) (Aduen). (3) 79-0.45xPAT or 90-0.60xTAP depending on the value of PAT.B) .10 patients enrolled to PVRT comparing the echocardiographic measurement (Chemla) with RHC. Results: in the first part of the study was found a high correlation between the 3 equations: Chemla-Aduen, R2=0.91; Chemla-Kitabatake, R2=0.87; Aduen-Kitabatake, R2=0.91. In the second part comparing the MPAP-Chemla and RHC we obtained high correlation: in time 0, 30 min and recovery: (R2=0.87, 0,99,0.98, respectively). Both parts of the study showed limits concordance satisfactory with mean value of the difference between the methods close to 1 in the t30 and tR of the TRVP. Conclusion: the methods dependent on the measurement of the TR are effective and reliably for estimating MPAP. The Chemla’s method is useful in the PVRT.