Targeting percutaneous transluminal septal ablation for hypertrophic obstructive cardiomyopathy by intraprocedural echocardiographic monitoring

Background: Percutaneous septal ablation has evolved as an alternative to surgery for reducing symptoms and outflow gradients in patients with hypertrophic obstructive cardiomyopathy. Intraprocedural echocardiographic imaging can improve clinical and hemodynamic results. Growing experience with this method has additionally shown that threatening necrosis of the myocardium distant from the septal target region can be detected. Methods and Results: Percutaneous septal ablation was performed in 162 patients (80 women, 82 men; aged 54.1 +/- 15.5 years); 131 of whom mere targeted by intraprocedural myocardial contrast echocardiography. In 11 patients (7%), an atypical target vessel or a perfusion area distant from the expected septal target region was detected, leading to a target vessel change. Permanent pacing was necessary in 14 patients (9%). Three patients (2%) died, After 3 months, the mean New York Heart Association functional class was reduced in the returning 159 patients from 2.8 +/- 0.5 to 1.3 +/- 1.0 (P < .0001) along with a gradient reduction from 77 +/- 35 to 12 +/- 22 mm Hg at rest, and from 147 +/- 43 to 44 +/- 45 mm Hg with provocation (P < .0001 each). The main reason for unsatisfactory gradient reduction was suboptimal scar placement in the patients treated before the introduction of intraprocedural myocardial contrast echocardiography. Conclusions: Percutaneous septal ablation is an effective nonsurgical technique for reducing symptoms and outflow gradients in hypertrophic obstructive cardiomyopathy. Echocardiographic guidance adds substantially to safety and efficacy of the procedure and should therefore be considered routinely.