The Study On The Clinical Significance Of The QRS Complex In Lead ? Of ECG

Objective:To study the diagnostic efficacy of the lead ? Q/q wave in ECG.Methods:586 patients with coronary heart disease who were hospitalized for the first time from January 2014 to December 2018 in our department were selected.According to the shape of Q/q wave in lead ?,the patients were divided into non-Q/q wave group(258 cases),Q wave group(173 cases)and q wave group(155 cases).According to the number of Q/q wave in inferior leads,the patients were divided into lead ? group(204 cases),lead ?+avF group(54 cases),lead ?+aVF+II group(70 cases).Then the diagnostic efficacy of each group was calculated.Finally,the risk factors of coronary heart disease associated with Q/q wave in lead ? were analyzed.Result:1.Diagnostic results of subjects340 cases of coronary heart disease(65.9% of unstable angina,26.2% of acute non-ST-segment elevation myocardial infarction,1.2% of acute ST-segment elevation myocardial infarction,6.7% of microvascular angina),246 cases of undiagnosed coronary heart disease(35.8% of high blood pressure,21.1% of coronary atherosclerosis,17.1% of healthy people,13.8% of cardiovascular neurosis,9% of myocardial bridge,1.6% of dilated cardiomyopathy,0.8% of hypertrophic cardiomyopathy,0.4% of severe myocarditis,0.4% of pulmonary embolism).2.Data characteristicsMost of the patients are concentrated in men around 60 years old.The BMI index is overweight,especially in the Q wave group.Q wave group combination with smoking history,drinking history,family history,diabetes history were the most.Allgroups had a history of hypertension,and all were mainly grade 3 hypertension.The fasting blood glucose of the Q wave group and the q wave group were mildly abnormal.More blood lipids are in the normal range.The combination of hyperuricemia in each combination is about 13%.In addition,male,BMI,history of hypertension,history of diabetes,and fasting blood glucose were statistically different among the three groups.But no significant difference between the Q wave group and the q wave group.However,they were all statistically different from the Q/q-free group.3.Diagnostic efficacyThe sensitivity,specificity,negative predictive value,positive predictive value and accuracy of the ? lead Q/q wave diagnosis of coronary heart disease were 38.2%vs 24.7%,82.5% vs 71.1%,49.2% vs 40.6%,75.1%vs54.2%,56.8% vs 44.2%.In the Q-wave of the inferior leads,the specificity,positive predictive value,and accuracy of the single ? lead,?+avF lead,and II+?+avF lead diagnosis of coronary heart disease were 88.2% vs 96.3% vs 98%,65.5% vs 78% vs 89.6%,46.4% vs 45.9% vs48.5%.In the q-wave of the inferior leads,the accuracy of diagnosis of coronary heart disease by single ? lead,?+avF lead,and II+?+avF lead was 41% vs 43.5 vs43.7%.4.Risk factorsThe coronary heart disease risk factors of ? lead Q/q wave were age,male,fasting blood glucose and smoking history.Conclusion:1.For the Q/q wave of the inferior leads,especially the lead ? Q/q wave,comprehensive analysis should be combined with the patient's medical history,symptoms and signs to avoid missed diagnosis or misdiagnosis to improve cost-effectiveness.2.Patients with inferior wall leads q wave should be followed up to prevent cardiovascular events.