## 2 Methods  
### Data Collection  
The experiments were carried out with five healthy adult beagles weighing 10-13 kg. The subjects were anesthetized with pentobarbital sodium (30 mg/Kg) firstly, then laid down in the supine position for surgical operations. A catheter (Swan-Ganz F7, Edwards, Irvine, CA, USA) filled with a heparinized solution (500 units/mL) was inserted into the RV via the jugular vein. A calibrated catheter and high-fidelity blood pressure transducer (MLTO699, ADInstruments, Sydney, Australia) was used to record the intraventricular blood pressure signal. U-44069 (40 mg/mL) was injected into the upper limb vein of the subjects by a path formed by an intravenous infusion with an uncontrolled flow speed.  
This path remained open during the signal recording so that a new dose of U-44069 could be injected. At the same time, a microphone transducer (MLT201, ADInstruments, Sydney, Australia) was used to record external HS signals at the apex of the heart. The RVBP, HS signal, and (electrocardiography) ECG signal of lead I were simultaneously digitalized at sampling frequency 1 KHz (PL3508, PowerLab 8/35, ADInstruments, Sydney, Australia) with a 16-bit resolution. The microphone, blood pressure transducer, ECG electrical node, and associated electrical lines were kept in fixed positions. The experimental protocol was approved by the ethics committee of the School of Biomedical Engineering, Dalian University of Technology.  
The schematic diagram and experimental procedure of the measurement system were shown in Figure 1. The experimental procedure for each subject was divided into three stages. In the first stage, the signals were collected about 60 s prior to the U-44069 injection. In the second stage, U-44069 was injected into the vein to induce vasoconstriction via activation of the prostaglandin-endoperoxide receptor. The RVBP rose rapidly to a high level. In the third stage, the medicine injection stopped. The RVBP decreased gradually and returned to normal status. This process was repeated 3-10 times for a subject. In total, 32 records were obtained from the five subjects. Every subject was injected with the same dose of the medicine to induce the elevation of right ventricular blood pressure. However, each subject absorbed and metabolized the medicine's ability differently, which lead to the duration of stage 2 and stage 3 to be different. We called this phenomenon the individual difference in this paper. In each trail, the signal analysis was performed prior (stage 1), during (stage 2), and after (stage 3) acute pulmonary artery stenosis. The details of the data were displayed in Table 1, where the 32 trails included two records which only had the normal RVBP (before U44069 injection), such as #1 and #25. There were little RVBP changes in the record #1 and #25. Other records had a wide of RVBP changes. The minimum of RVSBP was 11.24 mmHg and the maximum was 86.37 mmHg. It was shown that the models were evaluated in such wide range of RVSBP. Figure 2 showed an example which gave typical cardiac cycles of the synchronously collected signals. This example was from the #7 record of Table 1.  
Figure 1: Schematic diagram of the measurement system and experimental procedure; (**a**) experiment setup; (**b**) experimental procedure. ECG: Electrocardiography; HS: Heart Sound; RVBP: Right Ventricular Blood Pressure.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Subject** & **No. Record** & **Time Length (s)** & **Num. of Cardiac Cycles** & **RVSBP Range (mmHg)** \\ \hline No. 1 (12.5 kg) & \#1 & 1177.45 & 955 & 23.07–24.54 \\  & \#2 & 1763.37 & 1193 & 22.38–45.55 \\  & \#3 & 2