Alcohol concentration in coronary sinus blood after transarterial alcohol ablation of the hypertrophied septum in hypertrophic obstructive cardiomyopathy

Background and objective: The size of the resulting myocardial necrosis var ies after percutaneous transarterial ablation (PTA) of hypertrophied septum in patients with hypertrophic obstructive cardiomyopathy (HOCM). It was th e aim of this study to discover whether the alcohol concentration in corona ry sinus (CS) blood is a useful and appropriate parameter and what conclusi ons can be drawn from it. Patients and methods: PTA was done in fourpatients (two women and two men, aged 30-53 years) with HOCM. Before the intervention the gradient across th e left ventricular outflow tract ranged form 20 to 80 mmHg, postextrasystol ic it ranged from 40 to 180 mmHg. 1 x 2 mi ethanol was injected into the fi rst septal branch in 3 patients, 2 x 2 mi in one. The alcohol concentration in coronary sinus blood was measured every 30 sec for up to 5 min before a nd after ablation. The amounts were compared with the size of the akinetic area in the echocardiogram and the maximal value of creatine kinase. as a m easure of the size of myocardial necrosis. Results: The left ventricular outflow gradient was reduced in all patients, to 0-30 mmHg and postextrasystolic to 30-90 mmHg. A pacemaker had to be im planted in one patient who developed a 3 degrees AV block. The alcohol conc entration in coronary sinus blood ranged from maximally 1.53 and 0.23 per t housand after 30 sec and then fell to 0.56-0.12 per thousand after 5 min. T he patient with the highest CS alcohol concentration also had the highest m aximal value for creatine kinase (68 mu mol/l) and the largest akinetic are a in the echocardiogram. Conclusion: The extent of myocardial necrosis can probably be estimated fro m the CS blood concentration of alcohol after alcohol ablation. If, after t he first injection, high alcohol concentrations are measured, further alcoh ol injections are not indicated.