Electrocardiogram interpretation in general practice

background  Common diagnostic test in GP (cardiac complaints)  Difficulties of interpreting ECG: GP and residents > cardiologists  More correct interpretation of ECG achieved by using interpretative ECG recorders

Objectives  To know the sensitivity and the specificity of ECG interpretation by both GPs and interpretative recorders.

Methods  Setting: Ebeltoft, Denmark  Population: 902 ECGs (randomised aged population)  Cross-sectional study  Gold standard: cardiologist ‘s interpretation  GPs not blinded to: –Results of interpretive ECG recorder –History and other clinical data  Cardiologist not blinded to: –Results of interpretive ECG recorder

Methods  10 % of random sample of ECG viewed by an other cardiologist,  Statistic tool: SPSS,  McNemar’s test: sensitivity and specificity of diagnoses made by both GPs and ECG recorders,  Kappa: interobserver agreement on the diagnoses made by two cardiologists.

Results  902 of 905 ECGs  429 men (47.6%), 473 women (52.4%)  Median age: 41 years (men and women)  Kappa = (95% CI: )

Results abnormal ECG M+ (cardio) M- cardio M+ (GP) 182 M- (GP)

Results abnormal ECG  If the sensitivity = 69.8%

Results abnormal ECG M+ (cardio) M- (cardio) M+ (MG) M- (MG)

Results abnormal ECG GPECG recorder Sensibility (p<0.001) 69.8%84.4% Spécificity (p<0.001) 85.7%75.6% PPV36.8%29.1% PNV96%97.6%

Results ischaemia or myocardial infarction GPECG recorder Sensibility (p<0.001) 22.6%64.5% Specificity (p<0.001) 94.1%84.5% PPV12.1%12.9% PNV97.2%98.5%

Results any bundle branch  Sensitivity and specificity: no significant difference

Conclusions  Higher sensitivity with ECG recorder than with GPs  false-negative low for recoder  stay very low in general  the GP have to attempt to achieve a better sensitivity (abnormal ECG reading by the recorder to a specialist, a training,…)  Higher specificity with GPs than with ECG recorder

Conclusions  PPV: low  PNV: high  Low prevalence of abnormal ECG in this population

Positive point  GPs never knew that their ECG interpretation skills will be evaluated  real skills of the GPs

Negative points  Not blinding of the GPs  Not blinding of the cardiologist  The same training in Belgium and in Denmark?  One ECG recorder; and the other ones?