Outcome of repair of myocardial bridging at the time of septal myectomy.
BACKGROUND
Myocardial bridging describes systolic compression of the muscular investment of a portion of an epicardial coronary artery. We evaluated the outcome of muscular bridge unroofing of the left anterior descending artery at the time of septal myectomy in patients with hypertrophic cardiomyopathy.


METHODS
We conducted a case-controlled study of 36 patients (23 men; median age, 42 years) with hypertrophic cardiomyopathy and myocardial bridging. Group 1 patients had septal myectomy and concomitant unroofing (n = 13), group 2 patients underwent myectomy alone (n = 10), and group 3 patients were treated medically (n = 13).


RESULTS
Angina was more prevalent preoperatively in group 1, 46% compared with 20% in group 2. Preoperative left ventricular outflow tract gradients of 67.8 ± 58.2 mm Hg and 74.1 ± 19.7 mm Hg were reduced to 1.9 ± 2.9 mm Hg in group 1 (p < 0.0001) and to 5.6 ± 8.8 mm Hg in group 2 (p < 0.0001). In the surgical groups, there were no early deaths or complications related to unroofing. Survival at 10 years was 83.3% in group 1 (p = 0.297), 100.0% in group 2, and 67.9% in group 3; there were no late sudden deaths. At follow-up, 77% in group 1 were asymptomatic compared with 70% of patients in group 2 (p = 0.19). There was no recurrent angina in group 1.


CONCLUSIONS
Myocardial unroofing can be performed safely at the time of septal myectomy for left ventricular outflow tract obstruction. Angina was improved, but we found no difference in late survival compared with patients who had myocardial bridging and myectomy alone. Unroofing should be considered in patients with angina who have significant left anterior descending artery bridging and require myectomy.
Division of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
Meghana R
MR
Kunkala
Division of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
Hartzell V
HV
Schaff
Division of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
Harold
H
Burkhart
Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
Gurpreet S
GS
Sandhu
Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
Daniel B
DB
Spoon
Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
Steve R
SR
Ommen
Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
Paul
P
Sorajja
Division of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota. Electronic address: jdearani@mayo.edu.
Joseph A
JA
Dearani
D000328:Adult; D000787:Angina Pectoris / Q000175:diagnosis / Q000209:etiology; D006348:Cardiac Surgical Procedures / Q000379:methods*; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D016022:Case-Control Studies; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006346:Heart Septum / Q000601:surgery*; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D054084:Myocardial Bridging / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D061214:Patient Safety; D012016:Reference Values; D018570:Risk Assessment; D015996:Survival Rate; D016896:Treatment Outcome; D014694:Ventricular Outflow Obstruction / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*
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