Abstract 14507: Feasibility of Alcohol Septal Ablation Using Nitroglycerine Tests for Refractory Hypertrophic Obstructive Cardiomyopathy With Labile Gradient
Backgrounds: Alcohol Septal Ablation (ASA) is an effective option for the patients with hypertrophic obstructive cardiomyopathy (HOCM) refractory to optimal medical treatment. Intra-ventricular obstruction is extremely labile depending on recording methods and conditions. Indeed, even for the patients previously proved significant pressure gradient (PG) by noninvasive test, invasive simultaneous recordings are often unable to detect significant PG. For such patients with labile obstruction, however, the feasibility of ASA with provocation tests including nitroglycerine has not been investigated.
Methods/Results: We performed 185 ASA procedures from 1998 to 2012. There were 42 cases (23%) whose baseline PG < 40mmHg by invasive simultaneous recordings, and then 33 cases received nitroglycerine tests both before and immediately after ASA were enrolled. We investigated the clinical characteristics, pressure recordings and echocardiography before and 1 year after ASA. There were 31 cases with outflow tract obstruction and 3 cases with mid-ventricular obstruction. The Peak CPK was 1182+/-406 IU/L, the ethanol dosage was 2.1+/-0.9 ml and the number of ablated branches was 1.4+/-0.7. The PGs before and immediately after ASA were shown in Figure. The provoked PGs significantly decreased immediately after ASA. (p<0.0001) All ASA procedures were successfully performed without additional DDD/ICD or 30-days mortality. During 2-years follow-up after the procedure, the symptoms improved in all patients (NYHA class 2.6+/-0.5 to 1.3+/-0.4, p<0.0001), and 2 cases died due to malignancy and senility, however, there was no cardiac death.
Conclusions: About a quarter of the ASA candidates had been not proved significant baseline PG by invasive method. NTG provocation test was feasible to confirm the acute effect, like as Valsalva’s maneuver and post extra-systole. ASA is a promising option also for the patients with labile obstruction.
- © 2013 by American Heart Association, Inc.