Introduction: T he standard extended surgical myec-tomy dramatically improves quality of life in patients with obstructive hypertrophic cardiomyopathy (HOCM) and heart failure symptoms, when performed by experienced surgeons at referral institutions. There are very few referral centers in Europe, so we considered of interest to report the importance of transaortic secondary chordal cutting associated with „one-piece” „shallow” myectomy in developing a new HOCM center in Romania.
Methods: At our institution, between May 2015 and April 2018, 42 consecutive patients with obstructive HCM and heart failure symptoms limiting quality of life, mean age 50+/-13 years, underwent transaortic „one piece” „shallow” (about one third of the initial thickness) septal myectomy associated with cutting of fibrotic secondary mitral valve (MV) chordae, in the absence of additional surgical procedures.
Results: Preoperatively, 22 patients (52.4%) were in New York Heart Association functional class III-IV and 20 (47.6%) patients were in class II, basal ventricular septal thickness ranged from 15 to 35 mm (mean 21.3±6 mm), peak LV outflow gradient under basal conditions or with provocative maneuvers ranged from 55 to 140 mmHg (median 75 mmHg) and grade 3 or 4 MV regurgitation was present in 15 (35.7%) of the 42 patients. In all patients we performed MRI imaging pre-operatively to precisely measure the septal thickness, to observe the presence of crypts and to precisely imagine the future one piece myectomy. There were no hospi-tal deaths within 30 days after surgery. No patients re-mained in NYHA III or IV class. Each of the 22 patients who were preoperatively in class III-IV, postoperatively had no or mild heart failure symptoms. The remaining 20 patients were free of functional limitation after sur-gery. Postoperative basal septal thickness ranged from 13 to 22 mm (mean 15.24±2.5 mm), peak LV outflow gradient resting or provoked was 14±7 mmHg, range 8 to 26 mmHg. MV regurgitation was absent or mild in 41 patients after surgery, and remained moderate-to-severe (grade 3) in only one. An average of 4 (range 2 to 10) MV secondary chordae was resected. No mitral valve prosthesis was performed.
Conclusions: Transaortic shallow ventricular septal myectomy associated with cutting of the secondary mi-tral valve chordae substantially improved symptoms, abolished the LV outflow gradient in all patients, and reduced or abolished MV regurgitation in over 97% of our patients with obstructive HCM. When associated with MRI planning, this technique permits a shallower „one piece” myectomy and demonstrates that a pro-gram of septal myectomy can be initiated with good results in new HOCM center with a very short learning curve.