Fragmented QRS (fQRS) complex drew a large number of research interests recent years.It said to be prevalent in patients with coronary artery disease and myocardial infarction.Researchers also found fQRS was a sign of myocardial scarring,myocardial focal necrosis and substandard perfusion in patients suffered acute myocardial infarction,and the relationship of fQRS with malignant arrhythmia and cardiovascular events in these patients was also investigated lately,patients with fQRS were said to have an unfavorable prognosis.We summarized the definition,pathogenetic mechanism of fQRS and the relationship with ventricular arrhythmia in this article to figure out the cardiovascular event's predictive value of fQRS in patients suffered with acute myocardial infarction.

Objective:To investigate the diagnostic value of ventricular tachycardia (VT) integral and VT integral with increased positive criteria in wide QRS wave tachycardia (WCT).Methods:The electrocardiogram characteristics of 146 patients with WCT from January 2013 to July 2018 in Liaocheng People′s Hospital of Shandong Province were retrospectively analyzed. The diagnostic value of VT integral, Brugada four-step, Vereckei four-step and increased positive criteria "V 1 to V 6 lead RS valley time ≥ 100 ms" and "initial excite velocity (Vi)/terminal excite velocity (Vt) ≤ 1" were studied. Results:The positive criteria from first to fifth and seventh of the VT integral had lower sensitivity but higher specificity, which was consistent with the principle. The accuracy, sensitivity and negative predictive value of VT integral were significantly lower than Brugada four-step and Vereckei four-step (51.4% vs. 83.6% and 80.8%, 34.6% vs. 92.5% and 93.5%, 35.2% vs. 74.2% and 72.0%), the specificity was significantly higher than Brugada four-step and Vereckei four-step (97.4% vs. 59.0% and 46.2%),and there were statistical differences ( P<0.05). The sensitivity of the VT integral with increased positive criteria "V 1 to V 6 lead RS valley time ≥ 100 ms" and "Vi/Vt ≤ 1" was significantly higher than that of VT integral (61.7% and 65.4% vs. 34.6%), and there was statistical difference ( P<0.05); additionally, the specificity did not decrease. Conclusions:The VT integral has higher specificity but lower sensitivity for WCT. When the VT integral fails to diagnosis, V 1 to V 6 lead RS valley time ≥ 100 ms and Vi/Vt≤ 1 can increase the positive standard, and improve the accuracy of VT further.

Objective: To observe the expression changes of Notch and nuclear factor-κB (NF-κB) signaling pathways in rat myocardium post myocardial infarction. Methods: Myocardial infarction was established by ligation of the left anterior descending coronary artery(MI group), sham rats (similar surgical procedure without coronary artery ligation) served as control, the rats were sacrificed at first week, 4th and 8th week after operation, the non-infarct myocardial tissue in both groups was obtained to detect the mRNA expression of Notch1, Dll4 and Hes1 by RT-PCR, the protein expression of NICD1 was detected by Western blot, the nuclear protein p65 content was detected to reflect the activation degree of NF-κB signaling in the cardiomyocytes. Results: The myocardial mRNA expression of Notch1 in MI group was significantly higher than in control group (1.68±0.35 vs. 0.47±0.12, P<0.05) at first week, and tended to be higher at the 4th week and 8th week (P>0.05). The mRNA expression of Dll4 and Hes1 was similar between the two groups at the three time points. NICD1 protein level was increased at the first week in MI group as compared with control group (1.31±0.33 vs.0.45±0.11, P<0.05), which tended also to be higher at the 4th week and 8th week post operation (P>0.05). For NF-κB activation study, the nuclear protein p65 content was higher at first week, 4th week and 8th week in MI group as compared with respective control groups (0.286±0.052 vs.0.049±0.016 (P<0.01), 0.247±0.056 vs. 0.043±0.018 (P<0.01), 0.120±0.033 vs. 0.044±0.009 (P<0.05)), the most significant increase was found in the first week. Conclusions Notch and NF-κB signaling pathways are actively involved in the process of ventricular remodeling after myocardial infarction. Notch1 and NF-κB signaling pathways are both activated at the first week after myocardial infarction, NF-κB signaling pathway activation after myocardial infarction continues up to 8 weeks. These two signal transduction pathways may thus serve as new targets for future intervention studies to prevent heart failure.