Background Although percutaneous transluminal septal myocardial ablation (PTSMA) has been considered to be a new interventional technique to treat patients with hypertrophic obstractive cardiomyopathy (HOCM), few studies have reported their long term efficiency. The aims of this study was to investigate electrocardiographic date and the long term outcomes in follow-up.
Methods This study included 66 patients (36 males, 48.6 ± 12.4 years) in our hospital who were treated using PTSMA from October 2001 to October 2012. The indication for PTSMA was restricted to symptomatic patients with maximal LVOTG >50 mmHg under basal conditions or >70 mmHg with provocative manoeuvres or after extrasystole. Alcohol was injected to the suitable septal branch. Clinical and echocardiogrphic follow-up date (1 month, 6 month, and every year) was completed for all patients.
Results The average follow-up duration was (41.0 ± 34.0 months, range, 12–144 months). The average septal thickness 6 months after operation were significantly lower than the preoperative one (17.6 ± 3.3 mm vs 19.2 ± 3.7 mm, p = 0.032), and the long term septal walls were ever thicker (16.6 ± 4.0 mm vs 19.2 ± 3.7 mm, p = 0.015). The average left ventricular outflow tract (LVOT) 6 months after operation were significantly lower than the preoperative one (17.5 ± 1.6 mm vs 16.0 ± 1.4 mm, p = 0.002), and the long term LOVT were ever wider (19.0 ± 3.0 mm vs 16.0 ± 1.4 mm, p = 0.000). The average LVOT gradient 6 months after operation were significantly lower than the preoperative one (30.0 ± 14.7 mmHg vs 107.0 ± 49.6 mmHg, p = 0.000), and the long term LVOT gradients were ever lower (29.7 ± 25.4 mmHg vs 107.0 ± 49.6 mmHg, p = 0.000). There were 40 patients returned routinely for checkups. During the follow-up period after operation, 1 all-cause deaths and 1 cardiac death occurred. There was no case of heart transplantation, premature ventricular extrasystole, postinterventional sustained ventricular tachycardia, or other arrhythmias. The most frequent major post-procedural complication was chronic heart failure (7 among 40, 17%), NYHA classification were II-III. There were 7 patients had right complete heart block (CHB), however, no patient had syncope or resuscitation.
Conclusion In this study, percutaneous transluminal septal myocardial ablations reduce septal thickness and LVOTG, as well as improve cilinical symptoms with the long term follow-up.