Abstract
Background: Nonsurgical septal reduction therapy (NSRT) has been shown to improve left ventricular outflow tract (LVOT) gradients, decrease septal thickness, and improve symptoms in patients with hypertrophic obstructive cardiomyopathy (HOCM). The major complication of this procedure has been the development of complete heart block (CHB) requiring permanent pacemaker implantation, which has been reported in up to 33% of patients in early studies. Since this procedure was first reported, there have been refinements in the technique such as the use of echocardiographic contrast material to localize the site of infarction, slower injection of alcohol, as well as improvement in balloon technology.
Hypothesis: We sought to determine the results of NSRT using echocardiographic contrast localization, slow injection of alcohol, and short balloon length. We theorized that the incidence CHB would be lower than earlier reported results using these refined techniques.
Methods: We performed 50 NSRT procedures on 46 patients using echocardiographic contrast localization, slow alcohol injection, and currently available balloons. Patients had an echocardiogram before, immediately after NSRT, and at 3 months, and a treadmill test before and at 3 months after NSRT. In the hospital, patients were observed for the development of CHB or other complications, and infarct size was determined by serial creatine kinase (CK) measurements.
Results: There was a decrease in the LVOT gradient from 84.2 (± 30.8) mmHg at baseline, to 18.5 (± 14.8) mmHg immediately after NSRT (p < 0.001). At 3 months, the gradient was not statistically different at 22.7 (± 22.2) mmHg (p = 0.27). The septal thickness decreased from 2.21 (± 0.66) cm at baseline, to 1.67 (± 0.51) cm at 3 months (p < 0.001). New York Heart Association symptom class improved from 3.2 (± 0.4) at baseline, to 1.1 (± 0.6) at 3 months (p < 0.001). Mean treadmill time in 30 patients was 235 (± 142) s at baseline, to 367 (± 159) s at 3 months (p < 0.001). Of the 50 procedures, 45 were performed in patients without a previously placed permanent pacemaker or intracardiac cardioverter defibrillator; only 3 (6.7%) of the 45 developed complete heart blocks required permanent pacing. While only three patients in the series had a preexisting left bundle‐branch block (LBBB), two of the three patients who required a permanent pacemaker had an LBBB before the procedure.
Conclusion: Using contrast echocardiographic localization, slow injection of alcohol, and shorter balloon catheters, there continues to be excellent improvement in LVOT gradients, septal thickness, and symptoms, with a reduced incidence of CHB requiring permanent pacemaker implantation. Left bundle‐branch block appears to be a strong predictor for the development of CHB after NSRT.
Keywords: hypertrophic cardiomyopathy, alcohol septal ablation, asymmetric septal hypertrophy, pacemaker, outflow tract obstruction, myectomy
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References
- 1. Spirito P, Seidman CE, McKenna WJ, Maron BJ: The management of hypertrophic cardiomyopathy. N Engl J Med 1997; 338:775–785 [DOI] [PubMed] [Google Scholar]
- 2. Maron BJ, Bonow RO, Cannon RO, Leon MB, Epstein SE: Hypertrophic cardiomyopathy. N Engl J Med 1987; 316:780–789 [DOI] [PubMed] [Google Scholar]
- 3. Wigle ED, Rakowski H, Kimball BP, Williams WG: Hypertrophic cardiomyopathy: Clinical spectrum and treatment. Circulation 1995; 92:1680–1692 [DOI] [PubMed] [Google Scholar]
- 4. Fananapazir L, Epstein ND, Curiel RV, Panza JA, Tripodi D, McAreavey D: Long‐term results of dual chamber (DDD) pacing in obstructive hypertrophic cardiomyopathy: Evidence for progressive symptomatic and hemodynamic improvement and reduction of left ventricular hypertrophy. Circulation 1994; 90:2731–2742 [DOI] [PubMed] [Google Scholar]
- 5. Maron BJ, Nishimura RA, McKenna WJ, Rakowski H, Josephson ME, Kieval RS: Assessment of permanent dual‐chamber pacing as a treatment for drug‐refractory symptomatic patients with obstructive hypertrophic cardiomyopathy. A randomized, double‐blind, crossover study (M‐PATHY). Circulation 1999; 99(22) 2927–2933 [DOI] [PubMed] [Google Scholar]
- 6. Linde C, Gandler F, Kappenberger L, Ryden L: Placebo effect of pacemaker implantation in obstructive hypertrophic cardiomyopathy. Pacing in cardiology (PIC) study group. Am J Cardiol 1999; 83:903–907 [DOI] [PubMed] [Google Scholar]
- 7. Schulte HD, Borisov K, Gams E, Gramsch‐Zabel H, Losse B, Schwartz‐kopff B: Management of symptomatic hypertrophic obstructive cardiomyopathy–long‐term results after surgical therapy. Thorac Cardiovasc Surg 1999; 47:213–218 [DOI] [PubMed] [Google Scholar]
- 8. McCully RB, Nishimura RA, Tajik AJ, Schaff HV, Danielson GK: Extent of clinical improvement after surgical treatment of hypertrophic obstructive cardiomyopathy. Circulation 1996; 94:467–471 [DOI] [PubMed] [Google Scholar]
- 9. Sigwart U: Non‐surgical myocardial reduction for hypertrophic obstructive cardiomyopathy. Lancet 1995; 346:211–214 [DOI] [PubMed] [Google Scholar]
- 10. Seggewiss H, Gleichmann U, Faber L, Fassbender D, Schmidt HK, Strick S: Percutaneous transluminal septal myocardial ablation in hypertrophic obstructive cardiomyopathy: Acute results and 3‐month follow‐up in 25 patients. J Am Coll Cardiol 1998; 31(2): 252–258 [DOI] [PubMed] [Google Scholar]
- 11. Lakkis NM, Nagueh SF, Kleiman NS, Killip D, Zuo‐Xiang HE, Verani MS, Roberts R, Spencer WH III: Echocardiography‐guided ethanol septal reduction for hypertrophic obstructive cardiomyopathy. Circulation 1998; 98:1750–1755 [DOI] [PubMed] [Google Scholar]
- 12. Lakkis NM, Sherif SF, Dunn JK, Killip D, Spencer WH III: Nonsurgical septal reduction therapy for hypertrophic obstructive cardiomyopathy: One‐year follow‐up. J Am Coll Cardiol 2000; 36:852–855 [DOI] [PubMed] [Google Scholar]
- 13. Faber L, Ziemssen P, Seggewiss H: Targeting percutaneous transluminal septal ablation for hypertrophic obstructive cardiomyopathy by intraprocedural echocardiographic monitoring. J Am Soc Echocardiogr 2000; 13:1074–1079 [DOI] [PubMed] [Google Scholar]
- 14. Runquist LH, Nielsen CD, Killip D, Gazes PC, Spencer WH III: Electrocardiographic changes after alcohol septal ablation therapy for obstructive hypertrophic cardiomyopathy. Am J Cardiol 2002; 90:1020–1022 [DOI] [PubMed] [Google Scholar]
- 15. Nagueh SF, Lakkis NM, Middleton KJ, Killip D, Zoghbi WA, Quinones MA, Spencer WH III: Changes in left ventricular diastolic function six months after non‐surgical septal reduction therapy for hypertrophic obstructive cardiomyopathy. Circulation 1999; 99:344–347 [DOI] [PubMed] [Google Scholar]
- 16. Mazur W, Nagueh SF, Lakkis, NM, Middleton KJ, Killip D, Roberts R, Spencer WH III: Regression of left ventricular hypertrophy after nonsurgical septal reduction therapy for hypertrophic obstructive cardiomyopathy. Circulation 2001; 103(11): 1492–1496 [DOI] [PubMed] [Google Scholar]
- 17. Nagueh SF, Stetson SJ, Lakkis NM, Dillip D, Perez‐Verdia A, Entman EL, Spencer WH III, Torre‐Amione G: Decreased expression of tumor necrosis factor alpha and regression of hypertrophy after nonsurgical septal reduction therapy for patients with hypertrophic obstructive cardiomyopathy. Circulation 2001; 103:1844–1850 [DOI] [PubMed] [Google Scholar]