This Article Abstract Full Text (PDF) All Versions of this Article: 111/17/2183    most recent 01.CIR.0000163547.03188.ACv1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Daimon, M. Articles by Liddicoat, J. R. Search for Related Content PubMed PubMed Citation Articles by Daimon, M. Articles by Liddicoat, J. R. Related Collections Echocardiography CV surgery: valvular disease Related Articles

(Circulation. 2005;111:2183-2189.)
© 2005 American Heart Association, Inc.

Imaging

Percutaneous Mitral Valve Repair for Chronic Ischemic Mitral Regurgitation

A Real-Time Three-Dimensional Echocardiographic Study in an Ovine Model

Masao Daimon, MD; Takahiro Shiota, MD; A. Marc Gillinov, MD; Motoya Hayase, MD; Marc Ruel, MD; William E. Cohn, MD; Steven J. Blacker, MS; John R. Liddicoat, MD

From the Cleveland Clinic Foundation, Cleveland, Ohio (M.D., T.S., A.M.G.); Beth Israel Deaconess Medical Center, Boston, Mass (J.R.L.); Massachusetts General Hospital, Boston (M.H.); University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.R.); Texas Heart Institute, Houston (W.E.C.); and Viacor, Inc, Wilmington, Mass (S.J.B.).

Correspondence to Takahiro Shiota, MD, Department of Cardiovascular Medicine, Desk F15, Cleveland Clinic Foundation, 9500 Euclid Ave, Cleveland, OH 44195. E-mail shiotat{at}ccf.org

Received September 24, 2004; revision received November 24, 2004; accepted December 7, 2004.

	Abstract

Top Abstract Introduction Methods Results Discussion References

 
Background— Although surgical annuloplasty is the standard repair for ischemic mitral regurgitation (IMR), its application is limited by high morbidity and mortality. Using 2D and real-time 3D echocardiography in an ovine model of chronic IMR, we evaluated the geometric impact and short-term efficacy of a percutaneous transvenous catheter-based approach for mitral valve (MV) repair using a novel annuloplasty device placed in the coronary sinus.

Methods and Results— Six sheep developed IMR 8 weeks after induced posterior myocardial infarction. An annuloplasty device optimized to reduce anterior-posterior (A-P) mitral annular dimension and MR was placed percutaneously in the coronary sinus. Mitral annular A-P and commissure-commissure dimensions and MV tenting area (MVTa) in 3 parallel A-P planes (medial, central, and lateral) were assessed by real-time 3D echocardiography with 3D software. The annuloplasty device reduced MR jet area from 5.4±2.6 to 1.3±0.9 cm² (P<0.01), mitral annular A-P dimension in both systole and diastole (24.3±2.5 to 19.7±2.4 mm; P<0.03; 31.0±3.9 to 24.7±2.1 mm; P<0.001), and MVTa at mid systole in all 3 planes (153±46 to 93±24 mm², P<0.01; 140±47 to 88±23 mm², P<0.03; and 103±23 to 87±26 mm², P<0.03).

Conclusions— Percutaneous coronary sinus–based mitral annuloplasty reduces chronic IMR by reducing mitral annular A-P diameter and MVTa. This suggests the potential clinical application of a new nonsurgical therapeutic approach in patients with IMR.

Key Words: catheters • echocardiography • mitral valve • myocardial infarction • regurgitation

	Introduction

Top Abstract Introduction Methods Results Discussion References

 
Ischemic mitral regurgitation (IMR), a consequence of left ventricular (LV) dysfunction despite a structurally normal mitral valve (MV), occurs in 19% of patients after myocardial infarction (MI).^1,2 Chronic IMR is an independent predictor of mortality; the greater the degree of mitral regurgitation (MR) is, the worse the prognosis is.³ Although surgical annuloplasty is the current standard treatment for IMR, the high morbidity and mortality associated with the surgical procedure limit its application in patients with IMR.^4–6 These findings point to the need for the development of alternative approaches for treatment of IMR.

See p 2154

Human IMR is a complex phenomenon that is related to alterations in annular and ventricular geometry.^7–13 Using real-time 3D (RT3D) echocardiography, we demonstrated that medial MV tenting area (MVTa) is an important determinant of MR severity in IMR.¹³ Clinical experience and experimental study,¹⁴ however, have demonstrated that reducing the distance between the anterior and posterior annulus (A-P diameter) by surgical annuloplasty reduces or eliminates IMR. These findings are related because it is likely that increasing leaflet coaptation by reducing mitral annular A-P dimension simultaneously reduces tenting area. Continued study of IMR in both human and experimental models with RT3D echocardiography is necessary to characterize and quantify these relationships.

Recently, several groups have reported development of percutaneous catheter-based approaches to mitral annuloplasty (PTMA) that exploit the anatomic proximity of the coronary sinus (CS) to the mitral apparatus.^15,16 These studies in animal models of acute IMR and rapid pacing-induced heart failure demonstrated the feasibility of CS-based annuloplasty. However, it is essential to explore this approach in relevant models of chronic IMR similar to the human clinical situation.^4–6 The ovine with posterior MI is considered to be an established IMR model.^8,17 The purpose of the present study was to evaluate the feasibility and short-term efficacy of a percutaneous transvenous catheter-based annuloplasty for MV repair in an ovine model of chronic IMR using 2D and RT3D echocardiography.

	Methods

Top Abstract Introduction Methods Results Discussion References

 
Animal Preparation for MI
IMR was created in sheep using the model of Llaneras et al.¹⁸ All animals were studied in compliance with the Principles of Laboratory Animal Care formulated by the National Society of Medical Research and the Guide for the Care and Use of Laboratory Animals published by the National Institutes of Health. A total of 31 Dorsett sheep (57 to 68 kg) were intubated, and anesthesia was induced with ketamine 100 mg/mL (11 mg/kg) and xylazine 20 mg/mL (0.11 mg/kg) with continuous hemodynamic and ECG monitoring. Anesthesia was maintained with isoflurane (1.5% to 3%). Through a left lateral thoracotomy, snares were placed around the proximal second and third obtuse marginal branches of the circumflex coronary artery as described previously.¹⁸ Before creation of MI, each animal was treated with a pharmacological protocol to prevent arrhythmias and maintain hemodynamic stability.¹⁹ Posterior MI was created by coronary artery occlusion with tightening of these snares. After coronary artery occlusion, animals were monitored for 2 hours, and the thoracotomy was then closed. In surviving animals, MR was assessed by echocardiography at 4 and 8 weeks after MI.

Of 31 sheep subjected to this protocol, 12 died either immediately or within 1 month of MI, and 11 failed to develop MR that was 2+ or greater within 8 weeks. Thus, 8 animals survived and developed IMR that was 2+ or greater. Because of poor echo windows, 2 of these animals were excluded from further study. The remaining 6 served as subjects for the evaluation of the feasibility and short-term efficacy of percutaneous annuloplasty in chronic IMR. At a minimum of 8 weeks after MI, animals were returned to the cardiac catheterization laboratory for assessment of IMR and device implantation.

Echocardiographic Assessment
On the day of device implantation, animals were placed in the right lateral decubitus position and studied by conventional 2D and RT3D echocardiography at baseline and immediately after device implantation with a Sonos 7500 ultrasound system (Philips). A phased-array 3.5- to 5-MHz probe and a matrix-array handheld transducer (x4 transducer) were used to obtain 2D and RT3D echo images, respectively. All 3D echo images were stored digitally on a compact disk; all 2D echo images were stored digitally on magneto-optical disks for offline analysis. The degree of MR was graded by an MR jet area using color Doppler technique with 2D echocardiography in the parasternal long-axis view, with the integrated evaluation program in the ultrasound system.

We used 3D computer software (TomTec, Co) to evaluate LV wall motion and dimensions, left atrial dimensions, and geometry of the mitral apparatus. To evaluate the geometry of the mitral apparatus, first, 2D diameters of the mitral annulus (A-P and commissure-commissure [C-C]) at systole and diastole were assessed (Figure 1). Next, 3 A-P equidistant parallel planes perpendicular to the C-C plane were defined for imaging the geometry of the medial, central, and lateral sides of the mitral leaflets as described in our previous study (Figure 1).¹³ At mid systole, MVTa, the area enclosed by the annular plane and 2 leaflets, and MV tenting height (MVTht), the minimal distance between the leaflet coaptation and the mitral annular plane, were measured in all 3 A-P planes (Figure 1). The same echocardiographic protocol was completed in 6 control sheep without MI to compare measurements between normal sheep and those with IMR.

View larger version (49K): [in this window] [in a new window]   Figure 1. Schematics of C-C plane and 3 A-P planes (left) and geometric measurements of mitral annulus (left) and MV (right). Moving and rotating cut planes on cross-sectional 3D image at MV level give C-C plane connecting both commissures and 3 A-P planes in medial (M), central (C), and lateral (L) sides of MV. AML indicates anterior mitral leaflet; PML, posterior mitral leaflet; Ao, aorta; LA, left atrium; and MVTht, MV tenting height.

Device Implantation
IMR animals were intubated and anesthetized as described previously on the day of device implantation. After baseline echocardiography, a 9F introducer sheath was placed in the left internal jugular vein and advanced into the CS. Coronary venography was performed through this sheath. The anterior interventricular branch of the great cardiac vein was identified and engaged with a standard exchange-length Glidewire (Boston Scientific). Over this wire, a multilumen 9F custom delivery catheter (Viacor, Inc) was advanced into the CS until the distal tip was in the anterior interventricular vein. Annuloplasty devices were introduced into the CS through the lumens of the custom catheter under fluoroscopic guidance (Figure 2).

View larger version (95K): [in this window] [in a new window]   Figure 2. Guidewire, multilumen delivery catheter, PTMA devices, and fluoroscopic images during percutaneous mitral annuloplasty. A, Distal portion of guidewire and multilumen delivery catheter with tips of 3 different PTMA devices. B, Magnified cross section of multilumen delivery catheter. If number of devices, up to 3, and stiffness of each device are varied, total stiffness can be magnified, increasing force delivered to posterior mitral annulus. C, D, Fluoroscopic images during PTMA. Guidewire was introduced into CS with its distal end in anterior interventricular vein under fluoroscopic guidance (C). Anterior-posterior remodeling of mitral annulus was achieved with annuloplasty device in CS (D). Guidewire from left image (C) is superimposed in white to illustrate geometric change. Note movement of CS and adjacent posterior annulus by annuloplasty device (arrows).

Each annuloplasty device is fabricated from a single piece of drawn nitinol wire to a particular length and stiffness profile. In our method, we can vary the number of devices (up to 3) and stiffness of each device in the multilumen custom catheter (Figure 2). With these combinations, the total stiffness can be magnified 6-fold, increasing the force delivered to the posterior mitral annulus. When positioned in the CS, the annuloplasty devices effected a graded conformational change in the mitral annulus that reduced A-P diameter and increased leaflet coaptation. Devices were added or interchanged systematically in the 9F multilumen custom delivery catheter to optimize the reduction in A-P mitral annular dimension and MR degree under the monitoring by 2D echocardiography. After each annuloplasty device adjustment, 2D and RT3D echocardiographic images were obtained. When maximum reduction of MR was achieved, the devices were left in place for 30 minutes. During each experiment, the degree of MR was enhanced by administering neosynephrine and intravenous lactated Ringer’s solution. Safety of diagnostic, temporary implantation of the PTMA device was assessed by pathological examination after the PTMA procedure. After temporary device placement, animals were euthanized at 7 days (n=3), 14 days (n=2), or 28 days (n=1). Excised hearts were examined by a trained pathologist blinded to treatment.

Safety of Long-Term Device Implantation
To assess the safety of long-term implantation, in 5 animals without MR, a prototype implant (9F in 3, 7F in 2) was placed. The animals were euthanized for histopathological examination at 50 days after implantation.

Statistical Analysis
All values are expressed as mean±SD. An unpaired t test was used to compare normal animals with those with IMR; a paired t test was used to compare MR with mitral annular diameter before and after device implantation in animals with IMR. RT3D echocardiographic variables in all 3 A-P planes during device implantation in animals with IMR were evaluated by repeated-measures ANOVA, testing for the mitral annuloplasty effect, local effect in 3 A-P planes, and their interaction. Fisher’s protected least-significant-difference test was used for the post hoc test. A value of P<0.05 was considered statistically significant.

	Results

Top Abstract Introduction Methods Results Discussion References

 
Changes in LV Chamber and Mitral Annulus in IMR
Coronary artery occlusion produced posterior LV wall motion abnormalities. Compared with normal sheep, those with IMR had increased LV and left atrial diameters and decreased posterior LV wall thickness (Table 1). Compared with normal sheep, those with IMR had increased A-P mitral annular diameter at both diastole and systole (31.0±3.9 versus 24.2±2.5 mm and 24.3±2.5 versus 18.8±2.1 mm; P<0.01 for both) and increased C-C mitral annular diameter in systole (28.5±3.1 versus 23.7±2.0 mm; P<0.01).

View this table: [in this window] [in a new window]   TABLE 1. LV, Left Atrial, and Mitral Annular Diameter in Normal Sheep and Those With IMR

Mitral Valvular Deformation in IMR
In normal sheep, there was no difference in MVTht or MVTa between the echocardiographic planes (Table 2). In contrast, in sheep with IMR, there were asymmetric changes in MV tenting, with increased MVTht and MVTa in the medial plane compared with the lateral plane. Compared with normal sheep, those with IMR had larger MVTht in medial and central planes and larger MVTa in all planes.

View this table: [in this window] [in a new window]   TABLE 2. Differences in Mitral Valve Tenting Between Normal Sheep and Those With IMR

Impact of Annuloplasty
Placement of the annuloplasty device reduced MR jet area from 5.4±2.6 to 1.3±0.9 cm² (P<0.01) (Figure 3 and Table 3). The mitral annular A-P diameter was significantly reduced both in systole (24.3±2.5 to 19.7±2.4 mm; P<0.03) and diastole (31.0±3.9 to 24.7±2.1 mm; P<0.001) by device implantation, although the mitral annular C-C diameter was unaffected (Table 3). In terms of mitral valvular geometry, MVTht and MVTa in all 3 A-P planes were significantly decreased by device implantation (Figures 4 and 5). Annuloplasty device placement caused greater reductions in MVTht and MVTa in the medial A-P plane than in the lateral A-P plane (P<0.05 and P<0.01; Figures 4 and 5). Annuloplasty device implantation did not cause significant changes in heart rate (101±13 to 99±9 bpm), systemic blood pressure (systolic, 149±46 to 137±36 mm Hg; diastolic, 93±38 to 92±41 mm Hg), or ST segments on ECG. In each case, the CS was patent without perforation after temporary device placement. There was no damage to the MV, the LV, or adjacent coronary arteries.

View larger version (39K): [in this window] [in a new window]   Figure 3. Annuloplasty device significantly reduced MR jet area and A-P diameter in mitral annulus (right) vs baseline (left) in chronic IMR. LA indicates left atrium.

View this table: [in this window] [in a new window]   TABLE 3. Effect of Annuloplasty on Mitral Annular Diameter and MR

View larger version (40K): [in this window] [in a new window]   Figure 4. RT3D echocardiographic images of MV during mid systole in medial (left), central (middle), and lateral (right) A-P planes at baseline (top) and after device implantation (bottom). MV tenting (top arrow) was significantly improved in medial A-P plane by device implantation in CS (lower arrow) vs lateral A-P plane. LA indicates left atrium.

View larger version (12K): [in this window] [in a new window]   Figure 5. Impact of device implantation on MV tenting. Device implantation reduced all measures of tenting. However, ANOVA revealed greater reduction in MVTht and MVTa in medial A-P plane vs lateral A-P plane. *P<0.01 vs baseline; P<0.03 vs baseline; P<0.05 vs baseline.

Safety of Long-Term Device Implantation
In each case, the PTMA device was encapsulated and covered by an endothelial lining. The CS was patent without perforation, and there was no damage to the MV, the LV, or adjacent coronary arteries. There was no migration of the device during this time period.

	Discussion

Top Abstract Introduction Methods Results Discussion References

 
The key finding of this animal study is that PTMA acutely reduced IMR by shortening the mitral annular A-P diameter and reducing MVTa, particularly at the medial aspect. Furthermore, 50 days after device implantation, the animals revealed no major complications on histopathological examination.

IMR is a major and growing clinical problem. Recent reports document that 7 800 000 Americans suffer MI annually²⁰; 19% of these can be expected to develop significant MR.^1,2 Although MV dysfunction increases symptoms of heart failure and reduces survival in these patients, the MR is rarely addressed directly. Surgical annuloplasty is currently the only option for treatment, but this operation is associated with high morbidity and mortality, limiting its application.^4–6 However, patients who survive surgery frequently derive clinical benefit from the surgical annuloplasty.

Several potential mechanisms, including subvalvular papillary muscle displacement, which causes leaflet tenting, contribute to malcoaptation of the mitral leaflets in chronic IMR.^7–13 Despite this mechanistic complexity, annuloplasty alone produces satisfactory reduction of IMR in up to 80% of cases.²¹ This suggests that development of less invasive and safer methods of mitral annuloplasty might afford an important clinical benefit for large numbers of patients with IMR. There is currently great interest in using the CS to facilitate such approaches.

The CS is located in the atria-ventricular groove parallel to the posterior mitral annulus. The venous confluence runs from the CS ostium in the right atrium to the origin of the anterior interventricular vein, following the course of the posterior mitral annulus nearly from commissure to commissure. This anatomic proximity of the CS to the mitral annulus led to the hypothesis that mitral annuloplasty could be performed percutaneously by placement of a device in the CS. Percutaneous placement of mitral annuloplasty devices in the CS has been reported to reduce MR in models of global LV dysfunction¹⁵ and acute ischemia.¹⁶ Results from experimental models are encouraging. However, mechanisms that underlie these experimental forms of MR may differ from those present in chronic IMR.^{10,13,22–24} As for the difference between MR associated with global LV dysfunction and IMR, both MV anatomy¹³ and mitral annular geometry²³ were different between them, suggesting potentially different approaches of PTMA in these 2 types of MR. As for the difference between acute and chronic IMR, it was demonstrated that fibrous annular perimeter was dilated and height of the mitral annulus was reduced in ovine models with chronic IMR, whereas they were unchanged in acute IMR.²⁴ Moreover, it is known that LV dilatation and corresponding mitral annular geometric change after MI play an important role in the production of chronic IMR.¹⁰ Investigating the efficacy of PTMA in chronic IMR is clinically relevant because we often encounter patients with chronic IMR and consider the use of PTMA. This study was performed in an ovine model of chronic IMR. With occlusion of the obtuse marginal branches of the circumflex coronary artery, this ovine model is thought to be similar to human IMR caused by posterior MI. In this study, sheep with IMR had systolic and diastolic LV diameters (47±7 and 59±5 mm) similar to those observed in human IMR (50±1 and 64±1 mm).²⁵ That human clinical study with RT3D echo demonstrated increased mitral annular diameter and asymmetrical MV deformation (more severe tenting at the medial side than the lateral side) in IMR; in contrast, leaflet tenting was symmetrical in dilated cardiomyopathy. The present study in sheep with chronic IMR revealed similarities to human chronic IMR, including similar mitral annular dilatation and asymmetric MV deformation (more severe tenting at the medial than the lateral side). Thus, the animal model of chronic IMR used in this study closely approximates that observed in humans.

Various geometric deformations, including degree of MV tenting, have been linked to severity of human IMR. Excess tenting of the MV is strongly associated with the degree of functional MR in patients with systolic LV dysfunction.⁹ In one study of IMR, MVTa in the medial A-P plane was the strongest determinant of MR severity.¹³ This MV tenting is present in the ovine model of chronic IMR. In this model, reducing the distance between the A-P annulus by surgical annuloplasty reduces or eliminates MR.¹⁴ In the present study of IMR, 2D and RT3D echo demonstrated reduction in both MV tenting, particularly at the medial side, and A-P mitral annular diameter by a CS-based, percutaneous annuloplasty. The annuloplasty device effectively improved the asymmetric deformation of MV. These changes in the geometry of the mitral apparatus are believed to contribute to the reduction in IMR, similar to the effect observed with open surgical annuloplasty.

Study Limitations
This is an acute preliminary study of the feasibility and efficacy of percutaneous transvenous annuloplasty in an ovine model of chronic IMR. Long-term safety and efficacy of the device were not evaluated in animals with chronic IMR, although no major complications or migration was found in those without MR. Detailed studies of hemodynamic impact of percutaneous annuloplasty were not investigated. Chronic implantation studies are now underway to address these concerns.

In humans, the CS runs in close proximity to the circumflex coronary artery in the AV groove. This may introduce potential risk of damage to the circumflex coronary artery by placement of an annuloplasty device in the CS. Therefore, coronary angiography and venography before deployment of such a device in CS, as in this study, are necessary to avoid damage to the coronary circulation. As noted, long-term studies are warranted to confirm safety of CS-based mitral annuloplasty.

In this study, we did not evaluate anatomic differences in CS and mitral anatomy in sheep and humans. However, the CS has close proximity to the mitral annulus in humans,²⁶ suggesting the feasibility of human percutaneous annuloplasty.

Finally, we estimated MR severity by MR jet area by color Doppler technique. This method could be problematic in some cases. Because MR was not very severe in this study, it was difficult to obtain clear flow convergence even when the aliasing velocity was lowered. It was also difficult to obtain regurgitant volume by quantitative pulsed-Doppler methods by transthoracic echocardiography. As a result, we had to abandon more quantitative measurements of MR severity. However, detecting significant reductions in the color jet area to observe the efficacy of the device was relatively easy. This simple method was quite useful for this purpose.

Conclusions
The present study showed that percutaneous mitral annuloplasty using a novel device reduces MR by reducing MV tenting and mitral annular A-P diameter in an ovine model of chronic IMR. Further development and clinical trials of percutaneous annuloplasty are warranted.

	Acknowledgments

 
Disclosure

Drs Liddicoat, Cohn, and Gillinov have equity interests in Viacor, Inc. Drs Shiota and Hayase have served as consultants to Viacor, Inc.

	References

Top Abstract Introduction Methods Results Discussion References

 
1. Hickey MS, Smith LR, Muhlbaier LH, Harrell FE Jr, Reves JG, Hinohara T, Califf RM, Pryor DB, Rankin JS. Current prognosis of ischemic mitral regurgitation: implications for future management. Circulation. 1988; 78 (suppl I): I-51–I-59.[Medline] [Order article via Infotrieve]

2. Lamas GA, Mitchell GF, Flaker GC, Smith SC Jr, Gersh BJ, Basta L, Moye L, Braunwald E, Pfeffer MA. Clinical significance of mitral regurgitation after acute myocardial infarction: Survival and Ventricular Enlargement Investigators. Circulation. 1997; 96: 827–833.[Abstract/Free Full Text]

3. Grigioni F, Enriquez-Sarano M, Zehr KJ, Bailey KR, Tajik AJ. Ischemic mitral regurgitation: long-term outcome and prognostic implications with quantitative Doppler assessment. Circulation. 2001; 103: 1759–1764.[Abstract/Free Full Text]

4. Gillinov AM, Wierup PN, Blackstone EH, Bishay ES, Cosgrove DM, White J, Lytle BW, McCarthy PM. Is repair preferable to replacement for ischemic mitral regurgitation? J Thorac Cardiovasc Surg. 2001; 122: 1125–1141.[Abstract/Free Full Text]

5. Grossi EA, Goldberg JD, LaPietra A, Ye X, Zakow P, Sussman M, Delianides J, Culliford AT, Esposito RA, Ribakove GH, Galloway AC, Colvin SB. Ischemic mitral valve reconstruction and replacement: comparison of long-term survival and complications. J Thorac Cardiovasc Surg. 2001; 122: 1107–1124.[Abstract/Free Full Text]

6. Dahlberg PS, Orszulak TA, Mullany CJ, Daly RC, Enriquez-Sarano M, Schaff HV. Late outcome of mitral valve surgery for patients with coronary artery disease. Ann Thorac Surg. 2003; 76: 1539–1547.[Abstract/Free Full Text]

7. Kaul S, Spotnitz WD, Glasheen WP, Touchstone DA. Mechanism of ischemic mitral regurgitation: an experimental evaluation. Circulation. 1991; 84: 2167–2180.[Abstract/Free Full Text]

8. Gorman JH III, Gorman RC, Plappert T, Jackson BM, Hiramatsu Y, St John-Sutton MG, Edmunds LH Jr. Infarct size and location determine development of mitral regurgitation in the sheep model. J Thorac Cardiovasc Surg. 1998; 115: 615–622.[Abstract/Free Full Text]

9. Yiu SF, Enriquez-Sarano M, Tribouilloy C, Seward JB, Tajik AJ. Determinants of the degree of functional mitral regurgitation in patients with systolic left ventricular dysfunction: a quantitative clinical study. Circulation. 2000; 102: 1400–1406.[Abstract/Free Full Text]

10. Otsuji Y, Handschumacher MD, Liel-Cohen N, Tanabe H, Jiang L, Schwammenthal E, Guerrero JL, Nicholls LA, Vlahakes GJ, Levine RA. Mechanism of ischemic mitral regurgitation with segmental left ventricular dysfunction: three-dimensional echocardiographic studies in models of acute and chronic progressive regurgitation. J Am Coll Cardiol. 2001; 37: 641–648.[Abstract/Free Full Text]

11. Otsuji Y, Kumanohoso T, Yoshifuku S, Matsukida K, Koriyama C, Kisanuki A, Minagoe S, Levine RA, Tei C. Isolated annular dilation does not usually cause important functional mitral regurgitation: comparison between patients with lone atrial fibrillation and those with idiopathic or ischemic cardiomyopathy. J Am Coll Cardiol. 2002; 39: 1651–1656.[Abstract/Free Full Text]

12. Tibayan FA, Rodriguez F, Zasio MK, Bailey L, Liang D, Daughters GT, Langer F, Ingels NB Jr, Miller DC. Geometric distortions of the mitral valvular-ventricular complex in chronic ischemic mitral regurgitation. Circulation. 2003; 108 (suppl II): II-116–II-121.[Medline] [Order article via Infotrieve]

13. Kwan J, Shiota T, Agler DA, Popovic ZB, Qin JX, Gillinov MA, Stewart WJ, Cosgrove DM, McCarthy PM, Thomas JD. Geometric differences of the mitral apparatus between ischemic and dilated cardiomyopathy with significant mitral regurgitation: real-time three-dimensional echocardiography study. Circulation. 2003; 107: 1135–1140.[Abstract/Free Full Text]

14. Tibayan FA, Rodriguez F, Langer F, Zasio MK, Bailey L, Liang D, Daughters GT, Ingels NB Jr, Miller DC. Does septal-lateral annular cinching work for chronic ischemic mitral regurgitation? J Thorac Cardiovasc Surg. 2004; 127: 654–663.[Abstract/Free Full Text]

15. Kaye DM, Byrne M, Alferness C, Power J. Feasibility and short-term efficacy of percutaneous mitral annular reduction for the therapy of heart failure-induced mitral regurgitation. Circulation. 2003; 108: 1795–1797.[Abstract/Free Full Text]

16. Liddicoat JR, Mac Neill BD, Gillinov AM, Cohn WE, Chin CH, Prado AD, Pandian NG, Oesterle SN. Percutaneous mitral valve repair: a feasibility study in an ovine model of acute ischemic mitral regurgitation. Catheter Cardiovasc Interv. 2003; 60: 410–416.[CrossRef][Medline] [Order article via Infotrieve]

17. Gorman JH III, Jackson BM, Gorman RC, Kelley ST, Gikakis N, Edmunds LH Jr. Papillary muscle discoordination rather than increased annular area facilitates mitral regurgitation after acute posterior myocardial infarction. Circulation. 1997; 96 (suppl II): II-124–II-127.

18. Llaneras MR, Nance ML, Streicher JT, Lima JA, Savino JS, Bogen DK, Deac RF, Ratcliffe MB, Edmunds LH Jr. Large animal model of ischemic mitral regurgitation. Ann Thorac Surg. 1994; 57: 432–439.[Abstract]

19. Moainie SL, Gorman JH3rd, Guy TS, Bowen FW3rd, Jackson BM, Plappert T, Narula N, St John-Sutton MG, Narula J, Edmunds LH Jr, Gorman RC. An ovine model of postinfarction dilated cardiomyopathy. Ann Thorac Surg. 2002; 74: 753–760.[Abstract/Free Full Text]

20. Heart Disease and Stroke: 2004 Update. Dallas, Tex: American Heart Association; 2004.

21. Kongsaerepong V, Qin JX, Song JM, Shiota M, McCarthy PM, Gillinov AM, Shin JH, Williams T, Cosgrove DM, Thomas JD, Shiota T. Comparison between successful and failure mitral valve repair in ischemic mitral regurgitation: an intraoperative echocardiographic study. J Am Soc Echocardiogr. 2004; 17: 507. Abstract.

22. Lai DT, Timek TA, Tibayan FA, Green GR, Daughters GT, Liang D, Ingels NB Jr, Miller DC. The effects of mitral annuloplasty rings on mitral valve complex 3-D geometry during acute left ventricular ischemia. Eur J Cardiothorac Surg. 2002; 22: 808–816.[Abstract/Free Full Text]

23. Daimon M, Saracino G, Koyama Y, Qin JX, Kongsaerepong V, Fukuda S, Agler DA, Gillinov AM, Thomas JD. Local displacement and symmetrical deformation in ischemic mitral regurgitation: a novel computerized 3D echo method. Circulation. 2004; 110 (suppl III): III-422. Abstract.

24. Tibayan FA, Rodriguez F, Langer F, Zasio MK, Bailey L, Liang D, Daughters GT, Ingels NB Jr, Miller DC. Annular remodeling in chronic ischemic mitral regurgitation: ring selection implications. Ann Thorac Surg. 2003; 76: 1549–1554.[Abstract/Free Full Text]

25. Szalay ZA, Civelek A, Hohe S, Brunner-LaRocca HP, Klovekorn WP, Knez I, Vogt PR, Bauer EP. Mitral annuloplasty in patients with ischemic versus dilated cardiomyopathy. Eur J Cardiothorac Surg. 2003; 23: 567–572.[Abstract/Free Full Text]

26. Shinbane JS, Lesh MD, Stevenson WG, Klitzner TS, Natterson PD, Wiener I, Ursell PC, Saxon LA. Anatomic and electrophysiologic relation between the coronary sinus and mitral annulus: implications for ablation of left-sided accessory pathways. Am Heart J. 1998; 135: 93y–98.[CrossRef][Medline] [Order article via Infotrieve]

Related Articles:

Issue Highlights
Circulation 2005 111: 2151. [Extract] [Full Text]

Percutaneous Mitral Valve Repair: Are They Changing the Guard?

Peter C. Block
Circulation 2005 111: 2154-2156. [Extract] [Full Text]

This article has been cited by other articles:

				J.-H. Kim, O. Kocaturk, C. Ozturk, A. Z. Faranesh, M. Sonmez, S. Sampath, C. E. Saikus, A. H. Kim, V. K. Raman, J. A. Derbyshire, et al. Mitral cerclage annuloplasty, a novel transcatheter treatment for secondary mitral valve regurgitation: initial results in swine. J. Am. Coll. Cardiol., August 11, 2009; 54(7): 638 - 651. [Abstract] [Full Text] [PDF]

				C. E. Ruiz and I. Kronzon The Wishful Thinking of Indirect Mitral Annuloplasty: Will It Ever Become a Reality? Circ Cardiovasc Interv, August 1, 2009; 2(4): 271 - 272. [Full Text] [PDF]

				S. Sack, P. Kahlert, L. Bilodeau, L. A. Pierard, P. Lancellotti, V. Legrand, J. Bartunek, M. Vanderheyden, R. Hoffmann, P. Schauerte, et al. Percutaneous Transvenous Mitral Annuloplasty: Initial Human Experience With a Novel Coronary Sinus Implant Device Circ Cardiovasc Interv, August 1, 2009; 2(4): 277 - 284. [Abstract] [Full Text] [PDF]

				N. Piazza, A. Asgar, R. Ibrahim, and R. Bonan Transcatheter Mitral and Pulmonary Valve Therapy J. Am. Coll. Cardiol., May 19, 2009; 53(20): 1837 - 1851. [Abstract] [Full Text] [PDF]

				Y. Suzuki, A. C. Yeung, and F. Ikeno The Pre-Clinical Animal Model in the Translational Research of Interventional Cardiology J. Am. Coll. Cardiol. Intv., May 1, 2009; 2(5): 373 - 383. [Abstract] [Full Text] [PDF]

				P. Sorajja, R. A. Nishimura, J. Thompson, and K. Zehr A Novel Method of Percutaneous Mitral Valve Repair for Ischemic Mitral Regurgitation J. Am. Coll. Cardiol. Intv., December 1, 2008; 1(6): 663 - 672. [Abstract] [Full Text] [PDF]

				A. Plass, I. Valenta, O. Gaemperli, P. Kaufmann, H. Alkadhi, G. Zund, J. Grunenfelder, and M. Genoni Assessment of coronary sinus anatomy between normal and insufficient mitral valves by multi-slice computertomography for mitral annuloplasty device implantation Eur. J. Cardiothorac. Surg., April 1, 2008; 33(4): 583 - 589. [Abstract] [Full Text] [PDF]

				W. Y. Szeto, R. C. Gorman, J. H. Gorman III, and M. A. Acker Ischemic Mitral Regurgitation Card. Surg. Adult, January 1, 2008; 3(2008): 785 - 802. [Full Text]

				M. J. Davidson and D. S. Baim Percutaneous Catheter-Based Mitral Valve Repair Card. Surg. Adult, January 1, 2008; 3(2008): 1101 - 1108. [Full Text]

				L. P. Ryan, B. M. Jackson, L. M. Parish, H. Sakamoto, T. J. Plappert, M. St. John-Sutton, J. H. Gorman III, and R. C. Gorman Mitral Valve Tenting Index for Assessment of Subvalvular Remodeling Ann. Thorac. Surg., October 1, 2007; 84(4): 1243 - 1249. [Abstract] [Full Text] [PDF]

				T. A. Timek, S. L. Nielsen, D. T. Lai, D. Liang, G. T. Daughters, N. B. Ingels Jr, and D. C. Miller Effect of Chronotropy and Inotropy on Stitch Tension in the Edge-to-Edge Mitral Repair Circulation, September 11, 2007; 116(11_suppl): I-276 - I-281. [Abstract] [Full Text] [PDF]

				L. F. Tops, N. R. Van de Veire, J. D. Schuijf, A. de Roos, E. E. van der Wall, M. J. Schalij, and J. J. Bax Noninvasive Evaluation of Coronary Sinus Anatomy and Its Relation to the Mitral Valve Annulus: Implications for Percutaneous Mitral Annuloplasty Circulation, March 20, 2007; 115(11): 1426 - 1432. [Abstract] [Full Text] [PDF]

				A. J. Choure, M. J. Garcia, B. Hesse, M. Sevensma, G. Maly, N. L. Greenberg, L. Borzi, S. Ellis, E. M. Tuzcu, and S. R. Kapadia In Vivo Analysis of the Anatomical Relationship of Coronary Sinus to Mitral Annulus and Left Circumflex Coronary Artery Using Cardiac Multidetector Computed Tomography: Implications for Percutaneous Coronary Sinus Mitral Annuloplasty J. Am. Coll. Cardiol., November 21, 2006; 48(10): 1938 - 1945. [Abstract] [Full Text] [PDF]

				M. J. Mack Coronary Sinus in the Management of Functional Mitral Regurgitation: The Mother Lode or Fool's Gold? Circulation, August 1, 2006; 114(5): 363 - 364. [Full Text] [PDF]

				D. Maselli, F. Guarracino, F. Chiaramonti, F. Mangia, G. Borelli, and G. Minzioni Percutaneous Mitral Annuloplasty: An Anatomic Study of Human Coronary Sinus and Its Relation With Mitral Valve Annulus and Coronary Arteries Circulation, August 1, 2006; 114(5): 377 - 380. [Abstract] [Full Text] [PDF]

				J. M. Bernal, I. Garcia, D. Morales, C. Diago, B. Ruiz, F. Val, J. L. Ojeda, and J. M. Revuelta The 'Valve Racket': a new and different concept of atrioventricular valve repair. Eur. J. Cardiothorac. Surg., June 1, 2006; 29(6): 1026 - 1029. [Abstract] [Full Text] [PDF]

				J. H. Rogers, J. A. Macoviak, D. A. Rahdert, P. A. Takeda, I. F. Palacios, and R. I. Low Percutaneous Septal Sinus Shortening: A Novel Procedure for the Treatment of Functional Mitral Regurgitation Circulation, May 16, 2006; 113(19): 2329 - 2334. [Abstract] [Full Text] [PDF]

				M. A. Borger, A. Alam, P. M. Murphy, T. Doenst, and T. E. David Chronic Ischemic Mitral Regurgitation: Repair, Replace or Rethink? Ann. Thorac. Surg., March 1, 2006; 81(3): 1153 - 1161. [Abstract] [Full Text] [PDF]

				J. G. Webb, J. Harnek, B. I. Munt, P. O. Kimblad, M. Chandavimol, C. R. Thompson, J. R. Mayo, and J. O. Solem Percutaneous Transvenous Mitral Annuloplasty: Initial Human Experience With Device Implantation in the Coronary Sinus Circulation, February 14, 2006; 113(6): 851 - 855. [Abstract] [Full Text] [PDF]

				Percutaneous Annuloplasty Reduces MR in Sheep Journal Watch Cardiology, July 8, 2005; 2005(708): 3 - 3. [Full Text]

				P. C. Block Percutaneous Mitral Valve Repair: Are They Changing the Guard? Circulation, May 3, 2005; 111(17): 2154 - 2156. [Full Text] [PDF]

This Article Abstract Full Text (PDF) All Versions of this Article: 111/17/2183    most recent 01.CIR.0000163547.03188.ACv1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Daimon, M. Articles by Liddicoat, J. R. Search for Related Content PubMed PubMed Citation Articles by Daimon, M. Articles by Liddicoat, J. R. Related Collections Echocardiography CV surgery: valvular disease Related Articles