Table 4 Heartbeat classification methods. ISCH – ischemic heartbeats; PTCA - percutaneous transluminal coronary angioplasty; Se, Se, Acc – sensitivity, specificity and accuracy, respectively.

From: ECG features and methods for automatic classification of ventricular premature and ischemic heartbeats: A comprehensive experimental study

Type of heartbeats

Features

Classifier

Classification performance

Authors

NOR, particular minutes of ISCH

Morphological (QRS loop, ST-change vector magnitude, spatial ventricular gradient features)

Linear DFA

Se = 95.4%

Correa et al.3

Sp = 95.2 (for the 4th min of the PTCA)

NOR, mild ISCH

High-frequency QRS

Logistic regression

Se = 46%, Sp = 87%

Sharir et al.37

NOR, moderate/severe ISCH

Se = 69%, Sp = 86%

NOR, mild ISCH

Morphological (Q and R amplitudes, QRS slopes and energy, repolarization duration, normalized ST, etc.)

Logistic regression

Se = 77%, Sp = 88%

Llamedo et al. 2013 cinc38

NOR, moderate/severe ISCH

Se = 76%, Sp = 90%

NOR, ISCH

Morphological (QRS slopes)

Linear DFA

Se = 24%, Sp = 93%

Firoozabadi et al.4

NOR, ISCH

Morphological (samples of heartbeats)

k-NN, SVM

Acc(k-NN) = 94.6%

Murthy et al.5

Acc(linear SVM)=91.5%

Acc(RBF SVM)=95.3%

NOR, ISCH

Morphological

SVM

Se = 94.8%, Sp = 99.5%

Tseng et al.6

NOR, VPB and 2 others

Morphological, RR intervals, higher-order statistics

Linear DFA,

DFA: Acc(NOR)=88.6%

Doquire et al.10

SVM

Acc(VPB)=80.6%

SVM: Acc(NOR)=75.9%

Acc(VPB)=85.1%

NOR, VPB and 1 other

AR model coefficients and non-linear features

Linear DFA

Acc up to 88%

Balli et al.9

NOR, VPB

Morphological

SVM

Acc = 88.9%

Alajlan et al.7

NOR,VPB + 3 others (except ISCH)

Higher order statistics of wavelet coefficients

k-NN

Se(NOR) = 97.5%

Kutlu et al.12

Sp(NOR) = 95.3%

Se(VPB) = 87.6%

Sp(VPB) = 96.8%

NOR, VPB + 5 others (except ISCH)

Spectral

k-NN

Acc = 97.0%

Arif et al.8

NOR,VPB + 3 others (except ISCH)

Higher order statistics

k-NN

Se(NOR) = 100%

Karimifard et al.11

Sp(NOR) = 99.9%

Se(VPB) = 94.1%

Sp(VPB) = 99.8%

NOR, VPB

Kalman filter, polarogram

NB

Acc = 98.8%

Sayadi et al.13

NOR, VPB+10 others (except ISCH)

Morphological, spectral and statistic

SVM

Acc = 98.9%

Shen et al.14

NOR, ISM, ISE, VPB

Morphological (AreaD)

k-NN

Acc = 98.6%

Proposed method

NOR, ISM, ISE, VPB

Morphological (MorphD)

SVM

Acc = 93.5%

Proposed method