Percutaneous aortic valve replacement: an experimental study. I. Studies on implantation

OBJECTIVE: The purpose of this preliminary study was to devise a new surgical procedure for minimally invasive aortic valve implantation with a transluminal technique. METHODS: The new collapsible heart valve was prepared by mounting a porcine aortic valve, taken from a freshly slaughtered pig, into a self-expandable nitinol stent by means of a suture technique. The outer diameter of the valved stent ranged from 15 to 23 mm, and the length ranged from 21 to 28 mm. Before implantation in vivo, these valved stents were tested in an in vitro circulatory system. Only in vitro-tested valved stents with a pressure gradient of less than 7 mm Hg and regurgitation of I degrees or less were used for transluminal aortic valve implantation in vivo. Six of these valved stents were implanted in the descending aorta and 8 in the ascending aorta of anesthetized pigs. The catheter delivery system (22F) was extraperitoneally inserted through the left iliac artery or the infrarenal aorta. Measurements for transvalvular gradient, valvular opening and closure, blood-flow characteristics, regurgitation, and macroscopic analysis were performed at baseline and after the observation period (164 +/- 48 minutes). RESULTS: This preliminary study contained 14 animals. One animal died of ventricular fibrillation. Technical failure occurred in 2 pigs as a result of stent twisting. At the end of the observation period, the 11 successfully implanted valved stents demonstrated low transvalvular gradients (mean end-systolic Deltarho(max) of 5.4 +/- 3.3 mm Hg for the descending aorta group, 5.4 +/- 1.2 mm Hg for the supracoronary group, and 5.4 +/- 1.1 mm Hg for the subcoronary group), which did not differ from their in vitro gradients. Two-dimensional echocardiography demonstrated complete valvular closure and opening in 5 of 5 cases. Angiography indicated only a physiologic jet of regurgitation (0 degrees ) in 8 animals and mild (I degrees ) regurgitation in 3 animals. Color Doppler ultrasonography indicated no regurgitation in 5 of 5 cases and minor paravalvular leakage in 1 case. CONCLUSION: Aortic valved stents can be successfully implanted without thoracotomy by using a transluminal catheter technique. Long-term function of the valves remains to be established.     

Self-expandable valved stent of large size: off-bypass implantation in pulmonary position.

OBJECTIVE: To evaluate the feasibility of the off-bypass implantation of a self-expandable valved stent of large size in pulmonary position. MATERIALS AND METHODS: A glutaraldehyde preserved valved bovine jugular xenograft with internal diameter = 22 mm, mounted in two rings of nitinol 'Z' stent, expandable from 7 to 24 mm of internal diameter, was acutely evaluated in 6 adult pigs, mean body weight 55.6 kg (range 47-67 kg). Through a stent-graft delivery system (24 French) the self expandable valved stent was implanted off-bypass in pulmonary valve position by trans-ventricular approach through median sternotomy. RESULTS: The mean diameter of the main pulmonary artery measured was 21.7 +/- 1.6 mm. The mean length of the self expandable valved stent was 23.1 +/- 0.7 mm, the mean internal diameter 21.6 +/- 0.7 mm and the mean external diameter 26.3 +/- 0.7 mm. The mean peak pressure gradient recorded across the valve was 6.33 +/- 2.8 mmHg (range 4.5-9.6 mmHg) at Doppler echocardiography, and 4.5 +/- 3.1 mmHg (range 0-7 mmHg) at invasive measurement, with a pulmonary blood flow of 3.03 +/- 0.05 l/min. Intra-vascular ultrasound showed complete opening and closure of the valve (mean area reduction from 315.08 +/- 54.13 to 0 mm2). CONCLUSIONS: (a) Off-bypass implantation of self-expandable valved stent is feasible in pulmonary position; (b) off-bypass surgical approach allows for valved stent implantation of adult size with adequate hemodynamic functioning; and (c) intra-vascular ultrasound makes implantation and evaluation easy and reproducible.     

Comparison of supraannular and subannular pledgeted sutures in mitral valve replacement

Ten fresh canine hearts were used to compare the peak left ventricular pressure required to disrupt prosthetic mitral valves sutured in place with horizontal mattress sutures with either subannular or supraannular pledgets. Each group consisted of 5 animals. A 29-mm Medtronic mitral valve was secured in the mitral position with ten pledgeted sutures. The aorta was cannulated and normal saline solution was infused into the left ventricle until valvar disruption occurred. The peak pressure and the location and mechanism of disruption were then noted. At the peak left ventricular pressure required for valvar disruption, no individual sutures were broken. Instead, in all specimens a subannular myocardial rupture occurred in the posterior portion of the mitral annulus along the extent of the atrioventricular groove. In addition, the posterior wall of the left atrium dissected upward subsequently. Significantly greater pressures were required in the group with subannular suture placement as compared with the supraannular group (354 +/- 37 versus 236 +/- 33 mm Hg; p less than 0.0007). These data suggest that placement of horizontal mattress sutures with pledgets in the subannular position is superior to the currently recommended method of supraannular suture placement in mechanical valves.     

Surgical bypass of the systemic atrioventricular valve in children by means of a valved conduit

The surgical approach to relief of mitral stenosis in children is still a controversial problem. We describe our experience with four severely symptomatic children in whom a valved conduit from the left atrium to the left ventricle was successfully used to bypass a hypoplastic systemic atrioventricular valve. A left atrial-left ventricular extracardiac conduit was implanted in these patients with a hypoplastic mitral anulus and an adequate left ventricular chamber. There were no early or late deaths. Postoperative cardiac catheterization performed in all patients 1 month after the operation showed reduced size of the left atrium, a reduction of the left atrial-left ventricular gradient from a mean of 14 mm Hg to a mean of 5 mm Hg, and an increase of the left atrial outlet from a mean diameter of 10.7 mm to 28.7 mm (including the diameter of the native mitral valve plus the internal diameter of the valved conduit). The application of this unconventional operation in children with congenital or acquired stenosis of the systemic atrioventricular valve should be considered when the mitral valve obstruction cannot be relieved by conventional valve repair or replacement. Furthermore, the left atrial-left ventricular conduit does not preclude future alternative surgical options.     

Left ventricular outflow tract obstruction following mitral valve replacement: effect of strut height and orientation

The influence of strut position and strut height of Ionescu-Shiley bovine pericardial valves on the degree of left ventricular outflow tract (LVOT) obstruction was studied following mitral valve replacement (MVR) in hypertrophied left ventricles. Left ventricular hypertrophy was created in 6 lambs by constrictive banding of the descending thoracic aorta at 2 weeks of age. MVR was accomplished seven months later utilizing cardiopulmonary bypass and hypothermic cardioplegic arrest. Each animal underwent three consecutive valve replacements with 25-mm bovine pericardial valves randomly inserted in each of the following manners: (1) standard-profile valve with orientation of the struts out of the LVOT; (2) standard-profile valve with a strut oriented into the LVOT; and (3) low-strut profile investigational valve with a strut oriented into the LVOT. Gradients across the LVOT were measured after MVR and then following administration of isoproterenol hydrochloride (0.05 micrograms per kilogram of body weight per minute). No gradient was created with the struts oriented out of the LVOT with or without isoproterenol administration. When a strut was oriented into the LVOT without isoproterenol, the gradients were comparable with the standard- and low-profile valves (7 +/- 2 mm Hg versus 6 +/- 4 mm Hg, respectively). With isoproterenol, however, a significant difference in gradients between the standard- and low-profile valves (65 +/- 20 mm Hg versus 22 +/- 14 mm Hg, respectively) was observed when a strut was oriented into the LVOT. The results show that LVOT obstruction following MVR was related to the orientation of the strut of the bioprosthetic valve, and this obstruction was diminished with a decreased strut height of the Ionescu-Shiley prosthesis.     

A simple way to treat chronic atrial fibrillation during mitral valve surgery: the epicardial radiofrequency approach.

OBJECTIVE: We describe an original radiofrequency ablation technique to treat chronic atrial fibrillation in patients undergoing mitral valve surgery. Most of the procedure is carried out epicardially, in order to avoid an undue increase of surgical time and trauma. METHODS: The ablations are performed using a temperature-controlled multipolar radiofrequency catheter. Two encircling lesions around the ostia of the right and of the left pulmonary veins are carried out epicardially, usually before cardiopulmonary bypass. Through a conventional left atriotomy the ablation procedure is completed with two endocardial lesions connecting the two encirclings between them and to the mitral valve annulus. After the mitral valve procedure is performed, the left appendage is sutured. RESULTS: From February 1998 to May 1999, 40 patients with chronic atrial fibrillation (43. 1+/-51.9 months) underwent combined radiofrequency ablation and mitral valve surgery. Mean left atrial diameter was 56.8+/-10.7 mm. Mean cardiopulmonary bypass and aortic cross-clamp time were, respectively, 119.1+/-26.3 and 76.7+/-21.0 min. Mean postoperative blood loss was 287.2+/-186.6 ml. No reexploration for bleeding occurred. One patient died of pneumonia 12 days after operation. No patient needed permanent pacemaker implantation. Mean postoperative hospital stay was 7.3+/-5.6 days. At follow-up (mean 11.6+/-4.7 months), 30/39 (76.9%) of the patients were in stable sinus rhythm. All patients in sinus rhythm 3 months after operation recovered both left and right atrial contractility at echocardiographic control (mean 7.3+/-3.4 months). The left atrial diameter decreased significantly in patients recovering sinus rhythm. CONCLUSIONS: Epicardial radiofrequency ablation is a safe means to achieve surgical ablation of atrial fibrillation with a high success rate. The simplicity of the technique and the low procedure-related risk should dictate combined treatment virtually in all patients with atrial fibrillation undergoing open heart operations.     

Left ventricular outflow tract obstruction with mitral valve replacement in small ventricular cavities

The inference that mitral valve replacement (MVR) may produce left ventricular outflow tract (LVOT) obstruction has been made, but no comparative hemodynamic studies with various types of prostheses have been done. The purpose of the present study was to compare the gradients created across the LVOT with MVR in young sheep with small left ventricular cavities. Mitral valve replacement was accomplished using cardiopulmonary bypass and hypothermic cardioplegic arrest. Five animals were used for each of the following valves studied: 25-mm Ionescu-Shiley bovine pericardial valve, 25-mm Hancock porcine aortic valve, 2M-6120 28-mm Starr-Edwards ball-valve prosthesis, 25-mm Bj?rk-Shiley 60-degree flat tilting-disc prosthesis, and 25-mm St. Jude Medical hemidisc valve. Gradients across the LVOT were measured after MVR and then during infusion of isoproterenol hydrochloride (0.05 micrograms/kg/min). Following MVR, only the Starr-Edwards valve produced an LVOT gradient (32 +/- 23 mm Hg). Substantial gradients after MVR were seen, however, with isoproterenol administration with the Ionescu-Shiley (47 +/- 4 mm Hg), Hancock (13 +/- 8 mm Hg), and Starr-Edwards (65 +/- 30 mm Hg) valves but not with the low-profile valves (Bj?rk-Shiley and St. Jude Medical). The results of the present study demonstrate that MVR can produce LVOT obstruction. The greatest degree of obstruction was with the high-profile mechanical and bioprosthetic valves.     

Off-bypass implantation of a self-expandable valved stent between inferior vena cava and right atrium

A glutaraldehyde preserved valved bovine jugular xenograft mounted in a nitinol 'Z' stent, expandable from 7 to 28 mm of internal diameter, was evaluated in vitro (column of water developing a pressure of 45 mmHg and a mock loop including a pulsatile pump) and in vivo in five adult pigs with intra-vascular ultrasound to measure the inferior vena cava diameter via a retroperitoneal access. Through a stent-graft delivery system (24 French) the self expandable valved stent was implanted off-bypass in the inferior vena cava, between hepatic veins and cavo-atrial junction, with flow and pressure gradient recording. The mean length of the valved stent was 22.80+/-1.06 mm, the mean internal diameter 20.97+/-0.5 mm and the mean external diameter 26.67+/-0.9 mm. The valve leaking under pressure was 32.5+/-12.3 ml/min. The mean pressure gradient recorded across the self expandable valved stent implanted in the inferior vena cava was 1.0+/-0.5 mmHg (range 0-2 mmHg). Intra-vascular ultrasound showed partial opening and closing of the valve (mean area reduction from 148.5 to 81.5 mm2), with almost complete occlusion only during deep breaths. The in vitro and in vivo experiments confirmed the feasibility of potential application of the self-expandable valved stent implanted off-bypass in the inferior vena cava for late conversion of failing total cavo-pulmonary connection; intra-vascular ultrasound allows for adequate implantation and evaluation.     

A novel technique of supra-annular mitral valve replacement

We describe a new technique of mitral valve replacement in an 11.5-month-old, 5.5 kg baby whose native mitral annulus was only 14 mm. We successfully implanted a 16-mm mechanical valve in the supra-annular position by sewing it into a short polytetrafluoroethylene graft that was then sutured to the native annulus.     

Both leaflet preservation during mitral valve replacement: modified anterior leaflet preservation technique

BACKGROUND: Satisfactory results of bileaflet preserving mitral valve replacement (MVR) had forced several institutes to preserve both leaflets during MVR. Modifications were required to prevent the preserved tissue from interfering with prosthetic valve function, to implant an adequate size of valve and to prevent left ventricle outflow tract (LVOT) obstruction. MATERIALS AND METHODS: Conventional MVR was performed to 51 patients (group 1) and bileaflet preserving MVR was performed to 43 patients (group 2). Mitral anterior leaflet incised from the middle of the leaflet to mitral annulus without chordal injury in group 2 patients. Sutures were placed through the mitral annulus first and then passed from the bottom to the tip of anterior leaflet. Posterior leaflet was also preserved. Prosthetic valve was put down into the mitral annulus and sutures were ligated. Excessive anterior leaflet tissue was attached to left atrial wall. RESULTS: Cross-clamping time was 45 +/- 5.33 minutes versus 61.32 +/- 4.43 minutes (p = 0.0001) and total cardiopulmonary bypass time was 60.80 +/- 4.44 minutes versus 80.55 +/- 3.65 minutes (p = 0.0001) in groups 1 and 2, respectively. Inotropy requirement was higher in group 1 (p = 0.0058). When compared with preoperative values postoperative left ventricle ejection fraction (LVEF) increased both at rest (from 52.74% +/- 3.88% to 62.86% +/- 3.18%, p = 0.0001) and during exercise (from 53.16% +/- 3.16% to 64.11% +/- 2.46%, p = 0.0001) in bileaflet preserving MVR group. But in conventional MVR group LVEF decreased postoperatively both at rest (from 51.45% +/- 4.27% to 48.27% +/- 3.35%, p = 0.0001) and during exercise (from 54.47% +/- 7.36% to 42.96% +/- 3.58%, p = 0.0001). CONCLUSION: Leaflet preserving MVR operation not only improves the left ventricular performance but also reduces the mortality and morbidity after MVR. LVEF increases both at rest and during exercise. Risk of LVOT obstruction can be completely eliminated with our simple technique.     

Ischemia in three left ventricular regions: Insights into the pathogenesis of acute ischemic mitral regurgitation

BACKGROUND: Acute posterolateral left ventricular ischemia in sheep results in ischemic mitral regurgitation, but the effects of ischemia in other left ventricular regions on ischemic mitral regurgitation is unknown. METHODS: Six adult sheep had radiopaque markers placed on the left ventricle, mitral annulus, and anterior and posterior mitral leaflets at the valve center and near the anterior and posterior commissures. After 6 to 8 days, animals were studied with biplane videofluoroscopy and transesophageal echocardiography before and during sequential balloon occlusion of the left anterior descending, distal left circumflex, and proximal left circumflex coronary arteries. Time of valve closure was defined as the time when the distance between leaflet edge markers reached its minimum plateau, and systolic leaflet edge separation distance was calculated on the basis of left ventricular ejection. RESULTS: Only proximal left circumflex coronary artery occlusion resulted in ischemic mitral regurgitation, which was central and holosystolic. Delayed valve closure (anterior commissure, 58 +/- 29 vs 92 +/- 24 ms; valve center, 52 +/- 26 vs 92 +/- 23 ms; posterior commissure, 60 +/- 30 vs 94 +/- 14 ms; all P <.05) and increased leaflet edge separation distance during ejection (mean increase, 2.2 +/- 1.5 mm, 2.1 +/- 1.9 mm, and 2.1 +/- 1.5 mm at the anterior commissure, valve center, and posterior commissure, respectively; P <.05 for all) was seen during proximal left circumflex coronary artery occlusion but not during left anterior descending or distal left circumflex coronary artery occlusion. Ischemic mitral regurgitation was associated with a 19% +/- 10% increase in mitral annular area, and displacement of both papillary muscle tips away from the septal annulus at end systole. CONCLUSIONS: Acute ischemic mitral regurgitation in sheep occurred only after proximal left circumflex coronary artery occlusion along with delayed valve closure in early systole and increased leaflet edge separation throughout ejection in all 3 leaflet coaptation sites. The degree of left ventricular systolic dysfunction induced did not correlate with ischemic mitral regurgitation, but both altered valvular and subvalvular 3-dimensional geometry were necessary to produce ischemic mitral regurgitation during acute left ventricular ischemia.     

Do valved stents compromise coronary flow?

OBJECTIVE: The aim of the present study is to evaluate a new self-expanding valved stent design for minimal invasive aortic valve implantation and its interference with coronary flow. METHODS: An equine pericardial valve mounted onto a self-expanding nitinol stent (3F Therapeutics trade mark, CA, USA), outer diameter 23 mm, was evaluated (A) in vitro in a dynamic pulsatile mock loop and (B) in vivo in six calves (75+/-2.5 kg). In four animals valve stents were implanted on-pump and in two animals off-pump after induction of ventricular fibrillation. Target site for deployment was the orthotopic aorta, over the native valves. In vivo assessment was performed with intracardiac (AcuNav) and intravascular ultrasound including leaflet motion, planimetric valve orifice and residual-coronary\sinus-stent-index (RCSSI, distance stent to aortic wall/coronary diameter) calculations, coronary blood flow characteristics, transvalvular gradient, regurgitation and paravalvular leaking, in combination with continuous cardiac output measures. Macroscopic analysis was performed at necropsy. RESULTS: Two-dimensional intracardiac ultrasound showed good leaflet motion, with full valvular opening and closing in five of six valves. Planimetric valve orifice was 1.75+/-0.4 cm(2). There were no signs of coronary flow impairment with an RCSSI of 1.8+/-1.2. The implanted valved stents showed a low transvalvular gradient of 5.3+/-3.9 mmHg (mean, peak-to-peak) on invasive measurements and 4.7+/-2.5 mmHg in two-dimensional intracardiac sonography. One of six valves showed mild to moderate regurgitation and one of six valves a minor to moderate paravalvular leak due to size mismatch. CONCLUSIONS: This new self-expanding valved stent design allows for on- and off-pump aortic valve implantation in the orthotopic aorta, over the native valves without interference of the coronary blood flow and excellent acute valve function in properly sized devices.     

Volume reduction surgery for giant coronary sinus with valvular heart disease; report of a case

A 64-year-old male with giant left atrium and giant coronary sinus, who had aortic valve regurgitation, prosthesis valve paravalvular leakage in mitral position and prosthesis valve malfunction in tricuspid valve position, was successfully treated with double valve replacement, paravalvular leakage repair and volume reduction of left atrium and coronary sinus. Giant coronary sinus was about 70 mm in diameter and was thought to be induced by persistent left superior vena cava, high right atrium pressure and prosthesis valve malfunction in tricuspid valve position. Lung volume was so much increased by volume reduction of left atrium and coronary sinus and patient's symptoms were much improved.     

Mitral valve replacement for extensive calcification: half and half technique

A 50-year-old woman who had been undergoing hemodialysis for 18 years underwent mitral valve replacement because of mitral valve stenosis. Her mitral valve leaflet and annulus were highly calcified, and it was impossible to remove the posterior leaflet from the ventricular wall. At the time of surgery, noneverted horizontal mattress sutures were placed from the left ventricle to the left atrium on the anterior half of the mitral annulus and everted horizontal mattress sutures on the left atrial wall close to the calcified posterior annulus. A 25-mm St. Jude valve was seated successfully at a supra-annular position. The St. Jude valve is suitable for this technique because its leaflets protrude less into the left ventricle.     

Aortic valve replacement in adult patients with small aortic annuli

Fifty-five patients with small aortic annuli underwent valve replacement either isolated or combined with other procedures. Patch enlargement of the aortic annulus in the area of the noncoronary sinus was used in 32 patients. The width of the patch was calculated by multiplying the desired increase in diameter by pi and adding 8 mm for suturing. The remaining 23 patients had aortic valve replacement with a prosthesis larger than the aortic annulus. The prosthesis was sutured in a supraannular position in the area corresponding to the noncoronary sinus. This slightly tilted position does not compromise function of Carpentier-Edwards or Bj?rk-Shiley prostheses. Prosthetic gradients ranged from 0 to 18 mm Hg (9.2 +/- 3.9 mm Hg) in patients with patch enlargement of the aortic annulus and from 0 to 22 mm Hg (7.2 +/- 5.8 mm Hg) in patients with supraannular aortic prostheses. Although these techniques allow for insertion of prosthetic valves only one and two sizes larger than the aortic annulus, they appear to be satisfactory in most adult patients with a small aortic annulus.     

Pulmonary vein isolation by microwave energy ablation in patients with permanent atrial fibrillation

BACKGROUND: Atrial fibrillation is associated with significant morbidity and mortality. Microwave energy ablation (MW) is a new option for surgical treatment of permanent atrial fibrillation (pAF). We present our experience with surgical treatment of mitral valve disease (MVD), coronary artery disease (CAD), and aortic valve disease (AVD) and microwave ablation in patients with pAF. METHODS: In 202 consecutive patients (100 female, 102 male, age 68.3 +/- 8.1 years from 30.4 to 83.5 years, ejection fraction 25-80%, left atrial diameter 56 +/- 9.1 mm from 30 to 102 mm) with an indication for a cardiosurgical intervention, pAF was documented for 6.8 +/- 9.1 years. MW was performed using two different lesion concepts. In the first 140 patients we used an ablation line starting at the posterior mitral valve annulus and incorporated the interior of all pulmonary veins. After the first 137 patients we switched to a different ablation line concept. Starting at the posterior mitral valve the annulus ablation line additionally included the left atrial appendix. Another ablation circle around the pulmonary veins of both sides was created and both circles were connected. If opening of the right atrium was necessary additional isthmus ablation was performed. RESULTS: Survival rate was 98.5%. There were no ablation-related complications. In the 6-month follow-up 87 patients were in sinus rhythm (65%), in the 1-year follow-up 74 patients were in SR (62.2%). CONCLUSIONS: Microwave ablation is a safe and efficient method for surgical treatment of pAF in patients with a concomitant cardiosurgical procedure. The short duration for this additional procedure and easy application has made this procedure the method of choice in our institution for treatment of pAF in patients with cardiosurgical operations.     

Intra-atrial implantation of mitral valve prosthesis in 2 patients with active infective endocarditis complicated by mitral annular destruction]

This is a report of two patients with extensive destruction of the mitral annulus due to active infective endocarditis. Patient 1 was a 66-year-old female and the patient 2 was a 59-year-old male. In both patients medical therapy had failed to control endocarditis and emergency mitral valve replacements were carried out. At the operation special surgical techniques were necessitated, since insertion of artificial valves in the annulus was impossible because of the lack of the annular tissue due to destruction and excision. On the posterior commissure side, mitral valve prosthesis were sutured to the left atrial wall just above the anatomical mitral ring. Furthermore, in patient 2, a bovine pericardium collar attached to the prosthetic valve was sutured to the left atrial wall to secure fixation of the prosthetic valve. The postoperative courses were uneventful in both patients. This technique seems to be useful in patients with mitral annular destruction.     

A modified technique for mitral valve replacement

Between 1976 and 1983 254 mitral valve prostheses (243 Bj?rk-Shiley and 14 bioprostheses) were implanted in 252 patients using a modified technique. The age of patients varied from 26-72 years (mean 56 +/- 18 years). This technique allows an equidistant placement of sutures and accurate stitching of mitral valve annulus to the prosthetic valve ring. Follow-up averaged 67 +/- 21.6 months (3-7 years). Linearized aseptic dehiscence was 0.17 per 100 patient years. This technique was especially useful in patients with small left atrium and minimised the risk of a major prosthetic detachment.     

Annular or subvalvular approach to chronic ischemic mitral regurgitation?

OBJECTIVE: We sought to investigate whether annular or subvalvular interventions corrected chronic ischemic mitral regurgitation differently. METHODS: Sheep underwent placement of markers on the left ventricle, mitral annulus, papillary muscles (anterior and posterior), and both leaflet edges. A transannular suture (septal-lateral annular cinching) was anchored to the midseptal mitral annulus and externalized through the midlateral mitral annulus. Another suture (papillary muscle repositioning) from the posterior papillary muscle was passed through the mitral annulus near the posterior commissure and externalized. After 7 days, 3-dimensional marker data were obtained before inducing posterolateral myocardial infarction. After 7 weeks, animals in whom chronic ischemic mitral regurgitation developed (n = 10) were restudied before and after pulling septal-lateral annular cinching or papillary muscle repositioning sutures. End-systolic septal-lateral annular diameter and 3-dimensional displacement of the papillary muscles and leaflet edges were computed. RESULTS: Infarction increased mitral regurgitation (0.6 +/- 0.5 to 2.3 +/- 1.1); mitral annular septal-lateral dilation (4 +/- 1 mm); posterior papillary muscle displacement laterally (4 +/- 2 mm), posteriorly (9 +/- 3 mm), and toward the annulus (2 +/- 1 mm); posterior mitral leaflet apical tethering (3 +/- 1 mm); and interleaflet separation (+3 +/- 1 mm, P < .05 baseline vs chronic ischemic mitral regurgitation). Septal-lateral annular cinching reduced septal-lateral dimension (-9 +/- 3 mm), corrected lateral posterior papillary muscle displacement (4 +/- 1 mm) and septal-lateral interleaflet separation (-4 +/- 2 mm), and decreased mitral regurgitation (0.6 +/- 0.6, P < .05 septal-lateral annular cinching vs chronic ischemic mitral regurgitation) without affecting posterior leaflet restriction. Papillary muscle repositioning reduced septal-lateral diameter (-4 +/- 1 mm), moved the anterior papillary muscle closer to the annulus (2 +/- 1 mm), and relieved posterior leaflet apical restriction (2 +/- 1 mm, P < .05 papillary muscle repositioning vs chronic ischemic mitral regurgitation) but did not change lateral posterior papillary muscle displacement or decrease mitral regurgitation (1.9 +/- 1.2). CONCLUSIONS: Septal-lateral annular cinching moved the lateral annulus and the posterior papillary muscle closer to the septum and reduced mitral regurgitation unlike posterior papillary muscle repositioning, and thus the key mitral subvalvular repair component must correct posterior papillary muscle lateral displacement.     

Combined valve surgery in end-stage renal disease patient with porcelain aorta and mitral annulus calcification

A 66-year-old woman, who had been receiving regular hemodialysis for 11 years, was referred to our hospital because of heart failure due to combined valve disease complicated by porcelain aorta and mitral annulus calcification. We performed ascending aortic replacement under hypothermic arrest, and double valve replacement and tricuspid valve annuloplasty during rewarming. It was noted that the annulus of P3 of mitral valve had been replaced with atherosclerotic plaque containing calcification. We did not perform débridement. We placed non-everted horizontal mattress sutures from the left ventricle to the atrium on the anterior annulus and P1 to P2 annulus, and everted horizontal mattress sutures on the left atrial wall close to the calcified P3 annulus. Then, we successfully replaced the mitral valve with a 23-mm St. Jude Medical valve in a supra-annular position. The patient was discharged from the hospital 44 days after the operation.