Summary

Background: Left ventricular outflow gradient is associated with increased morbidity and mortality in hypertrophic cardiomyopathy. Alcohol septal ablation is the alternative to surgery in cases refractory to drug therapy. The implication of LVOG[1] measured 1 week post-ASA[2] for prediction of outcome is unknown.

Objective: To observe the pattern of LVOG course and prediction of long-term clinical and hemodynamic outcome of ASA.

Methods: Baseline clinical and echocardiographic parameters were prospectively recorded in 14 consecutive patients with a first ASA, at the time of ASA, 3 and 7 days after ASA (in-hospital) and 3 and ≥ 12 months after ASA (last follow-up).

Results: There was improvement in NYHA class, exercise parameters and LVOG in 11 of 14 patients (P < 0.005 in all). Maximal creatine kinase level was lower than 500 U/L in those without such improvement and 850 U/L or higher in successful cases. LVOG dropped from 79 ± 30 to 19 ± 6 mmHg after the ASA. LVOG was 50 ± 21 mmHg on day 3, 39 ± 26 on day 7, 32 ± 26 at 3 months and 24 ± 20 mmHg at last follow-up. LVOG identified 27% sustained procedural successes on day 3 and 73% on day 7. The overall predictive accuracy of the test for sustained success and failure was 36% on day 3 and 71% on day 7. Combination of maximal CK[3] and LVOG on day 7 showed four distinct outcome patterns: "early success" with low LVOG and high CK (73% of successful cases), "late success" with high LVOG and high CK, and "early failure" and "late failure" with both low CK and high or low LVOG, respectively

Conclusion: LVOG measurement 7 days post-ASA combined with maximal CK levels predicts late procedural outcome in the majority of patients