## 4 Discussion  
The purpose of this study was to prove that the phonation process suffers during acute heart failure. Therefore, the voice can be used as a prognostic marker and to monitor patients' health status. The data of the patients admitted to the hospital for acute heart failure have been evaluated. The subject data have been analyzed from the critical status (first day of admission) to the stable status (day of discharge). Out of 16, severe left ventricular systolic dysfunction was noted in 10 patients, with a hypersodium diet as precipitating factor. In comparison, six patients have had moderate left ventricular systolic dysfunction associated with bronchopneumonia with or without moderate to severe valvulopathy (Table 4). The machine-learning algorithm integrated the audio recordings from 15 patients. We used the last patient to test the algorithm, and he was classified accordingly and correctly after vocal analysis into the third NYHA stage at hospitalization and class II NYHA at discharge. Numerous factors are known to contribute to the development of heart failure (HF). The potential causes include coronary artery disease, hypertension, cardiomyopathies, valvular and congenital heart disease, arrhythmias, alcohol and drugs, high output failure (anemia, thyrotoxicosis, Paget's disease, etc. ), pericardial disease, and primary right heart \begin{table}
\begin{tabular}{c c c} \hline \hline
**Method** & **Results** \\ \hline SVM & Accuracy obtained using radial basis function (rbf) kernel = 0.709 \\  & Accuracy obtained using linear kernel = 0.618 \\  & Accuracy obtained using polynomial kernel = 0.527 \\  & Model 1: \\  & Maximum value of the loss function obtained during testing: 1.1447 \\ ANN & Maximum accuracy obtained during testing: 0.418 \\  & Model 2: \\  & Maximum value of the loss function obtained during testing: 1.3237 \\  & Maximum accuracy obtained during testing: 0.436 \\  & Model score obtained for KNN: 0.945 \\  & Confusion Matrix: \\ KNN & [[20 0 2] \\  & [0 13 0] \\  & [1 0 19]] \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Approach score. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Patient No.** & **Admission** & **Discharge** & **Mean Value of** & **Daily Water** & **Ntprobnp** & **Ntprobnp** \\  & **Weight** & **Weight** & **Daily Diuresis** & **Supply** & **Admission** & **Discharge** \\ \hline
1 & 62 kg & 58 kg & 2500 mL/24 h & 2000 mL/day & 3480 pg/mL & 1200 pg/mL \\
2 & 78 kg & 73 kg & 3500 mL/24 h & 1000 mL/day & 4638 pg/mL & 900 pg/mL \\
3 & 110 kg & 102 kg & 2600 mL/24 h & 750 mL/day & 17,545 pg/mL & 500 pg/mL \\
4 & 70 kg & 65 kg & 3000 mL/24 h & 2000 mL/day & 3131 pg/mL & 1000 pg/mL \\
5 & 78 kg & 74 kg & 3000 mL/24 h & 1500 mL/day & 3\(\sim\)3000 pg/mL & 1200 pg/mL \\
6 & 96 kg & 90 kg & 3500 mL/24 h & 1000 mL/day & 1207 pg/mL & 400 pg/mL \\
7 & 78 kg & 71 kg & 2700 mL/24 h & 1000 mL/day & 8987 pg/mL & 700 pg/mL \\
8 & 95 kg & 90 kg & 3100 mL/24 h & 1000 mL/day & 4277 pg/mL & 800 pg/mL \\
9 & 110 kg & 103 kg & 4000 mL/24 h & 1500 mL/day & 3664 pg/mL & 650 pg/mL \\
10 & 60 kg & 55g & 3800 mL/24 h & 1500 mL/day & 5200 pg/mL & 1105 pg/mL \\
11 & 85 kg & 79 kg & 3400 mL/24 h & 1000 mL/day & 15.300 pg/mL & 940 pg/mL \\
12 & 85 kg & 80 kg & 3500 mL/24 h & 1500 mL/day & 4325 pg/mL & 456 pg/mL \\
13 & 100 kg & 94 kg & 4000 mL/24 h & 2000 mL/day & 6800 pg/mL & 670 pg/mL \\
14 & 115 kg & 109 kg & 4500 mL/24 h & 1500 mL/day & 2262 pg/mL & 370 pg/mL \\
15 & 90 kg & 82 kg & 3800 mL/24 h & 1000 mL/day & 3797 pg/mL & 800 pg/mL \\
16 & 120 kg & 110 kg & 4300 mL/24 h & 1000 mL/day & 10.939 pg/mL & 589 pg/mL \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Evolution of water retention and NTproBNP during hospitalization. failure [45]. The meta-analyses conducted by [PERSON] et al. found an improvement in the survival rates secondary to CHF over the past 70 years. The estimated 1-year survival rate was 85.5%; however, the 5-year and 10-year survival rates were 56.7% and 34.9%, and most patients died directly from heart failure or cardiovascular diseases [46].