Correlation between ECG and MCE findings in HCM patients and clinical implications

Background

ST segment depression (STD) on electrocardiogram (ECG) is the most frequently used examination to detect myocardial ischemia and myocardial contrast echocardiography (MCE) is considered as a reliable technique to assess myocardial purfusion. However, association between two examinations and the underlying clinical implication in hypertrophic cardiomyopathy (HCM) patients is not fully illustrated.

Objective

To investigate the correlation between ECG and MCE findings in HCM patients and elucidating the underlying clinical implications.

Methods

Thirty-two patients diagnosed with HCM comprising the HCM cohort and 28 healthy individuals were enrolled as controls. The amplitude of ST segment depression (STD) was assessed, and the following MCE parameters: peak intensity (PI), area under the curve (AUC), rising slope (RS) and time to peak (TTP) were recorded and compared between the two groups, and correlation between MCE parameters and the extent of STD was calculated. Furthermore, HCM patients were categorized into three subgroups according to the severity of STD: ST1 group (0 < STD ≤ 0.1 mV); ST2 group (0.1 mV < STD ≤ 0.2 mV); ST3 group (0.2 mV < STD ≤ 0.3 mV), and data was compared among the four groups.

Results

ECG showed that all patients in the HCM group present STD (t = 8.294, P < 0.001). MCE showed that the values of PI, RS, and AUC were significantly reduced in the HCM group as compared to the control group (P < 0.001). Results of correlation analysis show no linear correlation between the PI values and the extent of STD (r = −0.348, P = 0.051). Of note, a significant difference in PI values between ST1 and ST3 (P = 0.01), ST2 and ST3 (P = 0.023) was observed.

Conclusion

Our findings reveal that STD greater than 0.2 mV strongly indicates myocardial perfusion impairment in HCM patients, and can serve as a reliable index for stratifying patients and identifying those at high risk.