Objective: To systematically evaluate the diagnostic value of delayed enhanced myocardial magnetic resonance imaging combined with multi-slice spiral CT in left ventricular function impairment of coronary heart disease and effect of mental pressure. Methods: The study selected 80 patients with coronary heart disease from March 2020 to September 2021. After MSCT and MRI were performed in all patients with coronary heart disease, the end diastolic volume, end systolic volume and unit output were calculated. The correlation and consistency of the two examination methods in various indexes were analyzed, and 80 patients with coronary heart disease were classified according to Killip classification, and the differences of cardiac function evaluated by MSCT and MRI at different levels were compared, as well as Cincinnati Prehospital Stroke Scale, CPSS. Results: In this study, 225 coronary arteries from CHD patients were analyzed by CAG. Of these, there were 31 cases of occlusion, 69 cases of severe stenosis, 82 cases of moderate stenosis, and 43 cases of mild stenosis. It was statistically significant (P<0.05), however the diagnostic accuracy of MRI was consistently higher than MSCT's. In terms of predicting CAG, there was no discernible difference between MSCT and MRI (P>0.05). There was no statistical significance in EDV, ESV, SV and LVEF cardiac function indexes measured by MSCT and MRI in this study (P>0.05). The results showed that EDV, ESV and LVEF had strong positive correlation (R =0.782, 0.713, 0.765, P<0.05) between the two CHD examination methods, while the two methods only had moderate positive correlation (R =0.513, P<0.05) on SV. P < 0.05); The Killip grading system classified patients into grade I, grade II, and grade III-IV. LVEF was used as a representative indicator of cardiac function. The results showed that there was no statistical significance in LVEF between MDCT and MRI in Killip grading (P>0.05). In MDCT and MRI, there was statistical significance between THE LVEF of Killip grading (P<0.05). ROC curve showed that MSCT AUC0.835 and sensitivity of 75.39% were significantly higher than MRI AUC0.752 and sensitivity of 70.28%, but MSCT specificity of 81.56% was significantly lower than MRI 82.46%. The combined experiment's overall accuracy was 0.932. The sensitivity and specificity of 85.46% and 90.98% were significantly higher than those of any of the above indexes, and the differences were statistically significant (P<0.05).  The  differences of CPSS were also statistically significant (P<0.05). Conclusion: Time-lapse enhanced cardiac magnetic resonance imaging and multi-slice spiral CT show good accuracy and correlation in determining the degree of arterial stenosis and left heart function in patients with coronary heart disease. The combination of the two has higher sensitivity and specificity in diagnosing left heart function damage in patients with coronary heart disease. It can reduce the mental pressure.