- Email: [email protected]
A new instrument to facilitate myectomy in subaortic hypertrophic stenosis
J
THoRAc CARDIOVASC SURG
1988;95:533-42
Brief communications A new instrument to facilitate myectomy in subaortic hypertrophic stenosis Francis Robicsek, MD, and Harry K. Daugherty, MD, Charlotte,
n.c.
From the Department of Thoracic and Cardiovascular Surgery and the Heineman Medical Research Laboratory at Charlotte Memorial Hospital and Medical Center, Charlotte, N.C.
A new instrument, a modified "back-biting" Kerrison rongeur, is presented and recommended for the treatment of hypertrophic subvalvular aortic stenosis. The spike of the instrument aUows the instrument to be engaged accurately and effectively into the anterior surface of the muscular ridge and appropriate obstructing tissue to be removed.
Despite the fact that the first operation for subaortic stenosis was performed 25 years ago, I the preferred surgical approach to this disease has yet to be defined.' Most authors agree, however, that removal of a core of the obstructing muscle generally is preferable to simple myotomy." We, ourselves, having experimented with various techniques of myectomy, found them usually less than satisfactory. This is especially true in tubular nonmembraneous obstruction, in which it is especially difficult to "grab," then to hold on to, and finally to excisefrail muscle tissue adequate in amount and proper in location. To overcome these difficulties we have developed the following technique. The method is based on the use of a modified "back-biting" Kerrison rongeur. The original instrument is altered in three principal ways: (1) The nonmoving "fixed" (upper) part of the rongeur is hollowed out to form a shell that serves as a receptable to receive the core of muscle resected. (2) The fact that the instrument is used to remove soft tissue instead of bone allowed us to make the wall of the hull relatively thin and its cutting edge sharp. (3) A spike was soldered to the distal This research made possible by a grant from the Heineman Medical Research Center of Charlotte, N.C. Address for reprints: Heineman Medical Research Center, P.O. Box 35457, Charlotte, NC 28235.
a
b
c Fig. 1. Resection of subaortic muscular hypertrophy with the modified rongeur. The instrument is inserted retrogradely through the ascending aorta. The spike is engaged into the muscular ridge and an appropriate portion of tissue is removed.
(lower) part of the instrument. This spike allows the operator to engage the instrument accurately and effectively into the inferior surface of the muscle ridge. After cardiopulmonary bypass is begun, the ascend533
534
The Journal of Thoracic and Cardiovascular Surgery
Brief communications
REFERENCES 1. Lillehei CW, Levy MJ, Varco RL, Wang Y, Adams P, Anderson RC. Surgical treatment of congenital aortic stenosis using cardiopulmonary bypass. Circulation 1962; 26:856-72. 2. Lavee JH, Porat L, Smolinsky A, Hegesh J, Neufeld HN, Goor DA. Myectomy versus myotomy in the surgical repair of discrete and tunnel subaortic stenosis. J THORAC CARDIOVASC SURG 1986;92:944-9. 3. Morrow AG, Brockenbrough EC. Surgical treatment of idiopathic hypertrophic subaortic stenosis: technic and hemodynamic results of subaortic ventricular myotomy. Ann Surg 1961;154:181-9. 4. Somerville J, Stone S, Ross D. Fate of patients with fixed subaortic stenosis after surgical removal. Br Heart J 1980;43:629-47. 5. Chiariello L, Agosti J, Vlad P, Subramanian S. Congenital aortic stenosis: experience with 43 patients. J THORAC CARDIOVASC SURG 1976;72:182-93.
An unusual lethal complication of preservation of chordae tendineae in mitral valve replacement C. K. Mok, FRCSE, D. L. C. Cheung, FRCS, C. S. W. Chiu, FRCSE, and M. Aung-Khin,' PhD, Hong Kong Fig. 2. Schematic presentation of subaortic resection with the spiked rongeur. ing aorta is cross-clamped, cardioplegic hypothermia is induced, and a transverse aortotomy is done to visualize the aortic valve. The subaortic obstruction is exposed by placing stay sutures into the commissures and by retracting the right coronary leaflet with a small vein retractor. The special rongeur is now introduced retrogradely into the left ventricle with its "jaw" turned toward the line falling between the left and right coronary cusps. The apical spike of the instrument is engaged into the ventricular side of the muscle ridge and, after the appropriateness of its position is assured, the jaws of the rongeur are closed and the muscle core is removed. If the muscle tissue, because of extensive fibrosis, is somewhat reluctant to "give," the removal of the core may be facilitated by cutting at the grabbing edge of the instrument with a No. 15 knife blade while the rongeur holds the muscle ridge firmly. This method was successfully applied in three consecutive patients operated on for subaortic stenosis. Compared to methods we used in the past, this technique significantly facilitated effective removal of the subvalvular obstruction.
From the Division of Cardiothoracic Surgery, Department of Surgery, University of Hong Kong, and Department of Pathology,' Grantham Hospital, Hong Kong.
In two patients, several chordae tendineae of the mural leaflet were preserved during mitral valve replacement. Hemorrhagic necrosis and spontaneous rupture of the preserved posterior papiUary muscle led to disc entrapment and the death of both patients.
It is generally accepted that during mitral valve replacement it is advantageous to preserve all or part of the mural leaflet and its chordae tendineae. i,2 Conversely, failure of the mitral valve prosthesis because of residual chordae tendineae has been reported.l' This paper describes two cases in which preservation of the chordae tendineae at mitral valve replacement resulted in fatal prosthetic valve dysfunction. Case reports. CASE 1. A 38-year-old woman with long-standing rheumatic mitral and aortic valvular disease underwent mitral and aortic valve replacement because of class III symptoms and
Address for reprints: C.K. Mok, The Grantham Hospital, 125 Wong chuk Hang Road, Hong Kong.
THoRAc CARDIOVASC SURG
1988;95:533-42
Brief communications A new instrument to facilitate myectomy in subaortic hypertrophic stenosis Francis Robicsek, MD, and Harry K. Daugherty, MD, Charlotte,
n.c.
From the Department of Thoracic and Cardiovascular Surgery and the Heineman Medical Research Laboratory at Charlotte Memorial Hospital and Medical Center, Charlotte, N.C.
A new instrument, a modified "back-biting" Kerrison rongeur, is presented and recommended for the treatment of hypertrophic subvalvular aortic stenosis. The spike of the instrument aUows the instrument to be engaged accurately and effectively into the anterior surface of the muscular ridge and appropriate obstructing tissue to be removed.
Despite the fact that the first operation for subaortic stenosis was performed 25 years ago, I the preferred surgical approach to this disease has yet to be defined.' Most authors agree, however, that removal of a core of the obstructing muscle generally is preferable to simple myotomy." We, ourselves, having experimented with various techniques of myectomy, found them usually less than satisfactory. This is especially true in tubular nonmembraneous obstruction, in which it is especially difficult to "grab," then to hold on to, and finally to excisefrail muscle tissue adequate in amount and proper in location. To overcome these difficulties we have developed the following technique. The method is based on the use of a modified "back-biting" Kerrison rongeur. The original instrument is altered in three principal ways: (1) The nonmoving "fixed" (upper) part of the rongeur is hollowed out to form a shell that serves as a receptable to receive the core of muscle resected. (2) The fact that the instrument is used to remove soft tissue instead of bone allowed us to make the wall of the hull relatively thin and its cutting edge sharp. (3) A spike was soldered to the distal This research made possible by a grant from the Heineman Medical Research Center of Charlotte, N.C. Address for reprints: Heineman Medical Research Center, P.O. Box 35457, Charlotte, NC 28235.
a
b
c Fig. 1. Resection of subaortic muscular hypertrophy with the modified rongeur. The instrument is inserted retrogradely through the ascending aorta. The spike is engaged into the muscular ridge and an appropriate portion of tissue is removed.
(lower) part of the instrument. This spike allows the operator to engage the instrument accurately and effectively into the inferior surface of the muscle ridge. After cardiopulmonary bypass is begun, the ascend533
534
The Journal of Thoracic and Cardiovascular Surgery
Brief communications
REFERENCES 1. Lillehei CW, Levy MJ, Varco RL, Wang Y, Adams P, Anderson RC. Surgical treatment of congenital aortic stenosis using cardiopulmonary bypass. Circulation 1962; 26:856-72. 2. Lavee JH, Porat L, Smolinsky A, Hegesh J, Neufeld HN, Goor DA. Myectomy versus myotomy in the surgical repair of discrete and tunnel subaortic stenosis. J THORAC CARDIOVASC SURG 1986;92:944-9. 3. Morrow AG, Brockenbrough EC. Surgical treatment of idiopathic hypertrophic subaortic stenosis: technic and hemodynamic results of subaortic ventricular myotomy. Ann Surg 1961;154:181-9. 4. Somerville J, Stone S, Ross D. Fate of patients with fixed subaortic stenosis after surgical removal. Br Heart J 1980;43:629-47. 5. Chiariello L, Agosti J, Vlad P, Subramanian S. Congenital aortic stenosis: experience with 43 patients. J THORAC CARDIOVASC SURG 1976;72:182-93.
An unusual lethal complication of preservation of chordae tendineae in mitral valve replacement C. K. Mok, FRCSE, D. L. C. Cheung, FRCS, C. S. W. Chiu, FRCSE, and M. Aung-Khin,' PhD, Hong Kong Fig. 2. Schematic presentation of subaortic resection with the spiked rongeur. ing aorta is cross-clamped, cardioplegic hypothermia is induced, and a transverse aortotomy is done to visualize the aortic valve. The subaortic obstruction is exposed by placing stay sutures into the commissures and by retracting the right coronary leaflet with a small vein retractor. The special rongeur is now introduced retrogradely into the left ventricle with its "jaw" turned toward the line falling between the left and right coronary cusps. The apical spike of the instrument is engaged into the ventricular side of the muscle ridge and, after the appropriateness of its position is assured, the jaws of the rongeur are closed and the muscle core is removed. If the muscle tissue, because of extensive fibrosis, is somewhat reluctant to "give," the removal of the core may be facilitated by cutting at the grabbing edge of the instrument with a No. 15 knife blade while the rongeur holds the muscle ridge firmly. This method was successfully applied in three consecutive patients operated on for subaortic stenosis. Compared to methods we used in the past, this technique significantly facilitated effective removal of the subvalvular obstruction.
From the Division of Cardiothoracic Surgery, Department of Surgery, University of Hong Kong, and Department of Pathology,' Grantham Hospital, Hong Kong.
In two patients, several chordae tendineae of the mural leaflet were preserved during mitral valve replacement. Hemorrhagic necrosis and spontaneous rupture of the preserved posterior papiUary muscle led to disc entrapment and the death of both patients.
It is generally accepted that during mitral valve replacement it is advantageous to preserve all or part of the mural leaflet and its chordae tendineae. i,2 Conversely, failure of the mitral valve prosthesis because of residual chordae tendineae has been reported.l' This paper describes two cases in which preservation of the chordae tendineae at mitral valve replacement resulted in fatal prosthetic valve dysfunction. Case reports. CASE 1. A 38-year-old woman with long-standing rheumatic mitral and aortic valvular disease underwent mitral and aortic valve replacement because of class III symptoms and
Address for reprints: C.K. Mok, The Grantham Hospital, 125 Wong chuk Hang Road, Hong Kong.