The Analysis Of The Electrocardiographic Characteristics Of Hypertrophic Obstructive Cardiomyopathy After Percutaneous Transluminal Septal Myocardial Ablation In Perioperative Period

Objectives To investigate electrocardiographic changes in patients with hypertrophic obstructive cardiomyopathy(HOCM) after percutaneous transluminal septal myocardial ablation (PTSMA) in perioperative period and to correlate electrocardiographic data with hypertrophic degree or the left ventricular outflow tract pressure gradients.Methods The PTSMA was performed on 48 patients with definitive HOCM. Resting electrocardiogram and Holter were recorded to compare the QRS duration, the abnormal Q Wave, the ST-T alteration, the the arrhythmias and heart rate variations before and after the PTSMA, and to correlate the electrocardiographic variables with hypertrophic degree or the left ventricular outflow tract pressure gradients.Results:(1)ECG representation was classified as 4 forms. Type I:R on V1-V1wave was not increased normally(25cases,52%). TypeII:narrow and deep Q wave on V4-V6 following higher R wave on V, (5cases,10%). Type III: arrow and deep Q wave on II,III,aVF or I,aVL. (3 cases,6%). Type IV:no Q wave was seen on all leads(15 cases,32%). (2)QRS waves duration was significantly increased (P<0.05), but no significant changes on the QRS duration after excluding the influents of bundle branch block. (3)New Abnormal Q wave was seen in 20 cases after PTSMA, disappearance of Q wave in 7 cases and deeper Q wave in 2 cases. Compared with the group of none Q wave change(19 cases),the group of Q wave change had no remarkable difference on the hypertrophic degree, alcohol dosage and decline of LVOT pressure gradient. (4). the instant new anterior ST Elevations on V1-V3 was seen in 33 patients after the PTSMA. Comparing the electrocardiograms before and after the PTSMA, the elevation of STV1was 0.11+0.06mv vs 0.25±0.12mv(P<0.05). The decline of ST,, was 0.04±0.05mv vs 0.11±0.05mv(P <0.05). (5) the right-bundle branch block before and after PTSMA was 4%(2/48) vs 47%(23/48), accelerated idioventricular rhythm 0%(0/48) vs 41% (20/48).Transient third degree AVB was 19 cases(39%) during procedure. (6) before and after the PTSMA, SDNN was 108.6±35.3 vs 118.3±27.1 (P <0.05), the average heart rate during the 24 hours was 72.3±9.4bpm vs 68.8±8.2 bpm(P<0.05) Conclusion PTSMA for HOCM could result in significant changes on the resting ECG and Holter, which include new Q waves, new bundle branch block, transient anterior ST segment elevation,,the declination of ST,, accelerated idioventricular rhythm, the decrease of SDNN and the increase of 24 hour average heart rate. No correlation was found between electrocardiographic changes and the left ventricular outflow tract pressure gradients which suggest that electrocardiographic changes would not have effect on efficacy of PTSMA.