Abstract:
AIM To verify our hypothesis that abolishing the hypertrophic myocardial mass in the septal region of the left ventricle by Liwen Procedure may result in a reduction of QRS amplitude on the electrocardiogram (ECG).
METHODS We enrolled 20 consecutive patients with hypertrophic obstructive cardiomyopathy (HOCM) who had undergone Liwen procedure in our Hypertrophic Cardiomyopathy Center from June 2016 to June 2017. ECG and echocardiogram were performed before and after Liwen Procedure and at each follow-up (1-week, 1, 2, 3, 6 months and 1 year). The Q wave, R wave and S wave amplitude of 12-lead ECG and interventricular septal thickness (IVS) by echocardiograms were measured in each patient. The sum of the ECG QRS amplitude on each lead was calculated. The QRS amplitude reduction was used as an improvement index.
RESULTS Our results showed that the leads with most improvement rate of the ECG QRS total amplitude in all the cases were V1 and V2, respectively at 90% and 85%. The QRS amplitude at baseline in V1 and V2 leads were positively correlated with anterior IVS thickness. In V1 and V2 leads, the reduction of QRS amplitude was significant after the operation. Similarly, the improvement of ECG QRS amplitude after the Liwen procedure tracked the gradual thinning of the IVS.
CONCLUSION The ECG QRS amplitude reduction in leads V1 and V2 may be one of the indicators for evaluating the postoperative interventricular septal reduction of the Liwen procedure.