High Order Statistics and Time-Frequency Domain to Classify Heart Sounds for Subjects under Cardiac Stress Test

Table 1

The area under curve (AUC), mean values and standard deviations of each feature (S1(), S2(), S1(), S2(), S1(), and S2()), and the maximum heart rate () reached for each subject.

Subject	1	2	3	4	5	6	7	8	Mean
AUC()	0.91	0.84	0.82	0.7	0.86	0.88	0.91	0.88	0.85
AUC()	0.9	0.84	0.94	0.77	0.89	0.88	0.96	0.8	0.87
AUC()	0.97	0.94	0.94	0.97	0.92	0.96	0.98	0.97	0.96
S1()	0.79 ± 0.05	1.02 ± 0.76	1.03 ± 0.35	0.71 ± 0.07	0.7 ± 0.03	0.8 ± 0.06	0.88 ± 0.37	0.74 ± 0.18	0.83 ± 0.13
S2()	0.61 ± 0.01	0.6 ± 0.03	0.66 ± 0.03	0.61 ± 0.01	0.5 ± 0.02	0.6 ± 0.04	0.61 ± 0.03	0.6 ± 0.03	0.59 ± 0.04
S1()	0.57 ± 0.15	0.63 ± 0.1	0.6 ± 0.1	0.65 ± 0.21	0.65 ± 0.08	0.63 ± 0.11	0.67 ± 0.11	0.56 ± 0.17	0.62 ± 0.03
S2()	0.29 ± 0.07	0.39 ± 0.12	0.26 ± 0.06	0.39 ± 0.14	0.4 ± 0.06	0.32 ± 0.13	0.32 ± 0.05	0.37 ± 0.11	0.34 ± 0.05
S1()	2.44 ± 0.82	2.7 ± 0.96	2.74 ± 1.33	2.91 ± 0.85	3.33 ± 1.18	3.18 ± 1.2	2.56 ± 0.87	3.12 ± 1.05	2.89 ± 1.07
S2()	7.47 ± 2.13	6.2 ± 1.92	6.74 ± 2.32	6.63 ± 1.6	7.02 ± 2.25	8.24 ± 2.35	7.8 ± 2.6	6.83 ± 1.49	7 ± 2.5
HR (bpm)	162	180	170	194	186	192	198	180