|
|
||||||||||
|
J Am Coll Cardiol, 2001; 37:1199-1209 © 2001 by the American College of Cardiology Foundation |



* Norwood Clinic and Kemp-Carraway Heart Institute, Birmingham, Alabama, USA
UCLA Medical Center, Los Angeles, California, USA
Centre Cardio-thoracique de Monaco, Monte Carlo, Monaco
University of Florence, Florence, Italy
|| Cleveland Clinic Foundation, Cleveland, Ohio, USA
Manuscript received June 1, 2000; revised manuscript received November 5, 2000, accepted December 20, 2000.
Reprint requests and correspondence: Dr. Constantine L. Athanasuleas, Department of Cardiac Surgery, Norwood Clinic, 1528 Carraway Boulevard, Birmingham, Alabama 35234
dra{at}norwoodclinic.com
| Abstract |
|---|
|
|
|---|
The goal of this study was to evaluate the safety and efficacy of surgical anterior ventricular endocardial restoration (SAVER). The procedure excludes noncontracting segments in the dilated remodeled ventricle after anterior myocardial infarction.
BACKGROUND
Anterior infarction leads to change in ventricular shape and volume. In the absence of reperfusion, dyskinesia develops. Reperfusion by thrombolysis or angioplasty leads to akinesia. Both lead to congestive heart failure by dysfunction of the remote muscle. The akinetic heart rarely undergoes surgical repair.
METHODS
A new international group of cardiologists and surgeons from 11 centers (RESTORE group) investigated the role of SAVER in patients after anterior myocardial infarction. From January 1998 to July 1999, 439 patients underwent operation and were followed for 18 months. Early outcomes of the procedure and risk factors were investigated.
RESULTS
Concomitant procedure included coronary artery bypass grafting in 89%, mitral valve (MV) repair in 22% and MV replacement in 4%. Hospital mortality was 6.6%, and few patients required mechanical support devices such as intraaortic balloon counterpulsation (7.7%), left ventricular assist device (0.5%) or extracorporeal membrane oxygenation (1.3%). Postoperatively, ejection fraction increased from 29 ± 10.4 to 39 ± 12.4%, and left ventricular end systolic volume index decreased from 109 ± 71 to 69 ± 42 ml/m2 (p < 0.005). At 18 months, survival was 89.2%. Time related survival at 18 months was 84% in the overall group and 88% among the 421 patients who had coronary artery bypass grafting or MV repair. Freedom from readmission to hospital for congestive heart failure at 18 months was 85%. Risk factors for death at any time after the operation included older age, MV replacement and lower postoperative ejection fraction.
CONCLUSIONS
Surgical anterior ventricular endocardial restoration is a safe and effective operation in the treatment of the remodeled dilated anterior ventricle after anterior myocardial infarction.
| ||||||||||||||||||||||
One large series examined the role of coronary artery bypass grafting (CABG) alone among patients with poor systolic function. Operative mortality was low and unrelated to (EF). However, among patients with EF <30%, five- and eight-year survivals were 65% and 45%, respectively (4). Another large study of CABG alone emphasized the importance of ventricular volume as an additional predictor of survival at five years. Patients with EF <30% had a five-year survival of 54% if the left ventricular end systolic volume index (LVESVI) was >100 ml/m2. Among these survivors, two-thirds had CHF (5).
Traditional surgical methods reduce volume only if a dyskinetic scar is present. Surgical repair of the postinfarction dyskinetic dilated ventricle evolved from simple excision and closure (6) to Jatenes septal exclusion (7). Volume reduction was not considered for the akinetic segment. In 1984, Dor et al. (8) first recognized that the physiological consequences of akinesia and dyskinesia were similar in their adverse effect on global ventricular size and function. They devised a surgical procedure in conjunction with CABG to reduce ventricular volume. The operation reduces ventricular size by excluding the noncontracting segment with an intraventricular patch. Dors procedure is applicable to both morphologies (9,10). Survival at eight years, including operative mortality in patients with severely depressed ventricular function (EF < 30%), was 69% (11).
The importance of volume reduction in the prognosis of postinfarction patients with systolic dysfunction and ventricular dilation has been established. A group was assembled to verify Dors operative experience in multiple centers and to assess intermediate clinical outcomes. The term "restoration" refers to surgical methods that reverse pathologic left ventricular remodeling (12). Surgical anterior ventricular restoration (SAVER) is an operation that reduces ventricular volume and utilizes Dors principles with some technical modifications.
| Methods |
|---|
|
|
|---|
Patient population. From January 1998 to July 1999, RESTORE members performed SAVER in 439 patients for postinfarction dilated cardiomyopathy. Median time from infarction to operation was reported among 263 patients and was 564 days (25th percentile: 80 days, 75th percentile: 2,487 days.) Age ranged from 25 to 89 years (mean 63 ± 10.7). Akinesia was seen in 64% of patients (279 patients), dyskinesia in 33% (146 patients) and unstated in 3% (14 patients).
Variables included date of operation, concomitant procedures including CABG, mitral valve (MV) repair or mitral replacement, method of myocardial protection during the restoration phase of the procedure (cardioplegia vs. open-beating) and mechanical support modalities, including intraaortic balloon counterpulsation (IABP), left ventricular assist device (LVAD) and extracorporeal membrane oxygenation (ECMO). Preoperative and postoperative EF and LVESVI were measured. Postoperative New York Heart Association functional class and rehospitalizations for CHF were documented.
Surgical procedure. The SAVER portion of the operation is performed immediately after CABG and MV repair or replacement if indicated. During SAVER, the infarcted anterior wall segment is incised parallel to the left anterior descending artery. Internal inspection of the ventricle identifies scarred and viable myocardium. Transmural palpation of contracting muscle precisely delineates the junction of viable and nonviable tissue (Fig. 1). An encircling suture at this junction excludes the scar from the ventricular cavity and creates a pursed opening, usually about 2 by 3 cm (Fig. 2) (13). A dacron patch is secured onto this opening and eliminates the akinetic or dyskinetic segment (Fig. 3). Finally, the excluded scar is folded over the patch to assure hemostasis (Fig. 4).
|
|
|
|
Statistics. Survival and freedom from rehospitalization were estimated both nonparametrically (15) and parametrically (16).
Univariable exploration of the association of variables with respect to death or rehospitalization included chi-square testing of frequency and Student t test for continuous variables. Correlations were sought between variables. Life tables stratified by categorical variables were compared by the log-rank test. Calibration of continuous variables was achieved by appropriate transformation of scale with the aid of decile risk analysis. Interaction terms were formed to identify differences in influence depending on myocardial protection method.
A directed technique of stepwise entry of variables was used (17). This was supplemented by bootstrap resampling, whereby 1,000 random samples of the data were drawn with replacement and an automated forward stepwise analysis performed with a p value criterion for retaining variables of 0.05. The relative frequency of occurrence of variables in these 1,000 models was used to inform the final selection of variables (18). The p value criterion for retention of variables in the final models was 0.1. Regression coefficients are presented ± 1 standard error.
The use of postoperative mechanical support was analyzed by logistic regression, using similar variable selection techniques.
Means are presented ± 1 standard deviation. Confidence limits (CL) of proportions, life table estimates and nomograms for multivariable analyses are asymptotic equivalents of one standard error.
| Results |
|---|
|
|
|---|
|
|
Postoperative mechanical support. In 439 operations, a small number of patients required IABP (7.7%), LVAD (0.05) or ECMO (1.3%) support. Multivariable logistic regression analysis showed that a concomitant MV repair/replacement or a lower postoperative EF predicted the need for support (Fig. 6). Preoperative EF did not predict the need for support.
|
Another center in the RESTORE group used crystalloid cardioplegic arrest during CABG or mitral procedure throughout patch placement in 88 patients. Mean EF was 20% and LVESVI was 109 ml/m2. Substantial inotropic support (epinephrine) and IABP use for low output were 15% and 40%, with aortic occlusion times of 50 and 100 min respectively.
Survival. Overall hospital mortality among the 439 patients was 6.6% (29 deaths). Mortality among 421 patients with CABG or MV repair was 5.1%. It was higher among 18 patients with CABG or MV replacement (28%, p < 0.0001).
Follow-up at 18 months revealed 17 late deaths. The risk of death was higher in the first month after operation but rapidly declined thereafter to a level of 6.5% per year by 12 months. Overall survival was 89.2% at 18 months. Time related survival was 84% at 18 months for the whole group and 88% for the group with CABG or MV repair (Figs. 7 and 8).
|
|
The influence of postoperative EF on 18-month survival for a 60-year-old patient without MV replacement is shown in Figure 9, which illustrates a more favorable outlook among patients with a high EF. The combined influences of advancing age and postoperative EF are shown in Figure 10. If the postoperative EF is high, advancing age has little impact on survival. However, if the postoperative EF is low, survival decreases markedly with advancing age.
|
|
Follow-up. Freedom from rehospitalization for CHF at 18 months after operation was 85%. Rehospitalization peaked between two and four months and leveled to 8.8% per year during the 18-month follow-up (Fig. 11). The risk of readmission was relatively insensitive to postoperative EF until it was <30%. (Fig. 12).
|
|
| Discussion |
|---|
|
|
|---|
Ventricular dilation is closely linked to risk of death after infarction (27). Successful thrombolysis after infarction can prevent or limit dilation but must occur within hours to achieve significant myocardial salvage and prevent dilation (28,29). The Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO) I trial examined the effect of early reperfusion on ventricular size using single plane ventriculography at 90 and 180 min into thrombolytic therapy for acute myocardial infarction. The authors found that LVESVI >40 ml/m2 was associated with an increased rate of hospital CHF and mortality at one year (30). Gaudron et al. (31) studied patients three years after infarction with successful reperfusion and found progressive ventricular dilation in 20%.
Preoperative ventricular volume also predicts the prognosis in ischemic cardiomyopathy treated by CABG alone. Yamaguchi et al. (5) observed patients with prior anterior myocardial infarction with EF < 30%. At five years, CHF occurred in 69% of patients with large ventricles (LVESVI > 100 ml/m2) and in only 15% of patients with smaller ventricles (LVESVI < 100 ml/m2). Mortality was similarly affected, demonstrating 54% survival in patients with large ventricles compared with 85% among patients with smaller ventricles.
Surgical anterior ventricular restoration decreases wall tension by reducing chamber size (Laplaces law). It attenuates oxygen requirement of the remote muscle, improving the oxygen supply/demand relationship. DiDonato et al. (32) and Dor have shown that volume reduction by infarct exclusion enhances regional systolic function in the myocardium remote from the anterior scar. An additional benefit of volume reduction may be shape alteration, which realigns muscle fiber orientation to allow optimal ejection (33).
The RESTORE group confirmed the feasibility of operating on akinetic scars. Palpation of the open-beating heart distinguished noncontracting akinetic segments that did not collapse during ventricular decompression. Operative and late mortality was low. In this study, average preoperative LVESVI of 109 ml/m2 was reduced to 69 ml/m2 postoperatively. After this significant volume reduction, left ventricular systolic function improved. Global EF increased from 29% to 39%. Mechanical support use was uncommon (9%) despite poor preoperative systolic function. At 18 months, 85% of discharged patients had not been readmitted for CHF.
Study limitations. The primary intent of this registry was to confirm Dors extensive experience and introduce surgeons to the concept of excluding the akinetic ventricle. Although many surgeons used cardioplegia-arrest throughout the procedure, others used the open-beating method of protection during patch placement. Hence, the operations were not precisely duplicated among centers.
Left ventricular end systolic volume index and EF were not obtained in all patients. Follow-up measurements were recorded in ambulatory patients between one and several weeks postoperatively. All volumes were obtained by ventriculography; however, biplane methodology was not used exclusively. Ejection fraction was calculated by echocardiography or ventriculography. Although EF was calculated by the same method for each patient before and after operation, it was not obtained at precisely the same postoperative interval.
Congestive heart failure evaluation was based on clinical assessment alone and provided by the same observer for each patient. The clinical criteria for readmission to the hospital for CHF were not defined.
Patients were not randomized to medical therapy, CABG alone, CABG/mitral procedures or a combination of these procedures with SAVER.
Conclusions. Our multicenter experience in 439 patients validates the safety and efficacy of SAVER and confirms Dors single center experience in 835 patients with dilated cardiomyopathy after anterior myocardial infarction (34). Surgical anterior ventricular restoration is associated with low operative mortality and infrequent use of mechanical support. Survival at 18 months was encouraging and rehospitalization for CHF was low.
The consequence of ventricular dilation after infarction is detrimental. Our results support the need for randomization of SAVER with medical therapy or CABG alone in postinfarction dilated cardiomyopathy. Furthermore, SAVER early after infarction may prevent late ventricular dilation. The RESTORE groups ongoing experience will further define the indications and optimal methods of restoration.
| Appendix |
|---|
|
|
|---|
| References |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
H. Subramanian, B. Kunadian, and J. Dunning Is it worth performing surgical ventricular restoration in patients with ischemic cardiomyopathy and akinetic but non-aneurysmal segments in the left ventricle? Interactive CardioVascular and Thoracic Surgery, August 1, 2008; 7(4): 702 - 707. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. K. Yankey, T. Li, A. Kilic, G. Cheng, A. Satpute, K. Savai, S. Li, S. L. Moainie, D. Prastein, C. DeFillipi, et al. Regional remodeling strain and its association with myocardial apoptosis after myocardial infarction in an ovine model. J. Thorac. Cardiovasc. Surg., May 1, 2008; 135(5): 991 - 998.e2. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Jacobs, R. Grunert, F. W. Mohr, and V. Falk 3D-Imaging of cardiac structures using 3D heart models for planning in heart surgery: a preliminary study Interactive CardioVascular and Thoracic Surgery, February 1, 2008; 7(1): 6 - 9. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. D. Glower and J. E. Lowe Left Ventricular Aneurysm Card. Surg. Adult, January 1, 2008; 3(2008): 803 - 822. [Full Text] |
||||
![]() |
M. T. Spoor and S. F. Bolling Nontransplant Surgical Options for Heart Failure Card. Surg. Adult, January 1, 2008; 3(2008): 1639 - 1648. [Full Text] |
||||
![]() |
C.-P. Hsu, C.-Y. Huang, J.-S. Wang, H.-I. Chiang, and C.-C. Shih Down-Regulation of Apoptosis After Left Ventricular Aneurysm Repair Ann. Thorac. Surg., October 1, 2007; 84(4): 1279 - 1287. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Langer, F. Rodriguez, A. Cheng, S. Ortiz, K. B. Harrington, M. K. Zasio, G. T. Daughters, J. C. Criscione, N. B. Ingels, and D. C. Miller Alterations in Lateral Left Ventricular Wall Transmural Strains During Acute Circumflex and Anterior Descending Coronary Occlusion Ann. Thorac. Surg., July 1, 2007; 84(1): 51 - 60. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. M. Fedoruk, C. G. Tribble, J. A. Kern, B. B. Peeler, and I. L. Kron Predicting Operative Mortality After Surgery for Ischemic Cardiomyopathy Ann. Thorac. Surg., June 1, 2007; 83(6): 2029 - 2035. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. B. Carmichael, R. M. Setser, A. E. Stillman, M. L. Lieber, N. G. Smedira, P. M. McCarthy, R. C. Starling, J. B. Young, J. A. Weaver, A. G. Lawrence, et al. Effects of Surgical Ventricular Restoration on Left Ventricular Function: Dynamic MR Imaging Radiology, December 1, 2006; 241(3): 710 - 717. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. O. O'Neill, R. C. Starling, P. M. McCarthy, N. M. Albert, B. W. Lytle, J. Navia, J. B. Young, and N. Smedira The impact of left ventricular reconstruction on survival in patients with ischemic cardiomyopathy Eur. J. Cardiothorac. Surg., November 1, 2006; 30(5): 753 - 759. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. D. Adams, L. M. Fedoruk, C. A. Tache-Leon, B. B. Peeler, J. A. Kern, C. G. Tribble, J. D. Bergin, and I. L. Kron Does Preoperative Ejection Fraction Predict Operative Mortality With Left Ventricular Restoration? Ann. Thorac. Surg., November 1, 2006; 82(5): 1715 - 1720. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Kilic, T. Li, T. D.C. Nolan, J. R. Nash, S. Li, D. J. Prastein, G. Schwartzbauer, S. L. Moainie, G. K. Yankey, C. DeFilippi, et al. Strain-related regional alterations of calcium-handling proteins in myocardial remodeling J. Thorac. Cardiovasc. Surg., October 1, 2006; 132(4): 900 - 908. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Burkhoff and A. S. Wechsler Surgical ventricular remodeling: A balancing act on systolic and diastolic properties. J. Thorac. Cardiovasc. Surg., September 1, 2006; 132(3): 459 - 463. [Full Text] [PDF] |
||||
![]() |
S. A.F. Tulner, P. Steendijk, R. J.M. Klautz, J. J. Bax, M. J. Schalij, E. E. van der Wall, and R. A.E. Dion Surgical ventricular restoration in patients with ischemic dilated cardiomyopathy: Evaluation of systolic and diastolic ventricular function, wall stress, dyssynchrony, and mechanical efficiency by pressure-volume loops. J. Thorac. Cardiovasc. Surg., September 1, 2006; 132(3): 610 - 620. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. G. Crespo-Leiro and J. J. Cuenca-Castillo Surgical treatment of heart failure: heart transplantation and ventricular restoration surgery Eur. Heart J. Suppl., September 1, 2006; 8(suppl_E): E39 - E42. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. S Kalkat, U. Dandekar, C. Smallpeice, J. Parmar, C. Satur, and A. Levine Left Ventricular Aneurysmectomy: Tailored Scar Excision and Linear Closure Asian Cardiovasc Thorac Ann, June 1, 2006; 14(3): 231 - 234. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Di Donato, P. Dabic, S. Castelvecchio, C. Santambrogio, J. Brankovic, L. Collarini, T. Joussef, A. Frigiola, G. Buckberg, L. Menicanti, et al. Left ventricular geometry in normal and post-anterior myocardial infarction patients: sphericity index and 'new' conicity index comparisons Eur. J. Cardiothorac. Surg., April 1, 2006; 29(Suppl_1): S225 - S230. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. A. Ribeiro, C. E. da Costa, M. M. Lopes, A. N. Albuquerque, F. Antoniali, G. A. A. Reinert, and K. G. Franchini Left ventricular reconstruction benefits patients with ischemic cardiomyopathy and non-viable myocardium Eur. J. Cardiothorac. Surg., February 1, 2006; 29(2): 196 - 201. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. O. O'Neill, R. C. Starling, Y. Khaykin, P. M. McCarthy, J. B. Young, M. Hail, N. M. Albert, N. Smedira, and M. K. Chung Residual high incidence of ventricular arrhythmias after left ventricular reconstructive surgery J. Thorac. Cardiovasc. Surg., November 1, 2005; 130(5): 1250 - 1256. [Abstract] [Full Text] [PDF] |
||||
![]() |
Developed in Collaboration With the American Colle, Endorsed by the Heart Rhythm Society, S. A. Hunt, W. T. Abraham, M. H. Chin, A. M. Feldman, G. S. Francis, T. G. Ganiats, M. Jessup, M. A. Konstam, et al. ACC/AHA 2005 Guideline Update for the Diagnosis and Management of Chronic Heart Failure in the Adult--Summary Article: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure) J. Am. Coll. Cardiol., September 20, 2005; 46(6): 1116 - 1143. [Full Text] [PDF] |
||||
![]() |
S. A. Hunt, W. T. Abraham, M. H. Chin, A. M. Feldman, G. S. Francis, T. G. Ganiats, M. Jessup, M. A. Konstam, D. M. Mancini, K. Michl, et al. ACC/AHA 2005 Guideline Update for the Diagnosis and Management of Chronic Heart Failure in the Adult--Summary Article: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure): Developed in Collaboration With the American College of Chest Physicians and the International Society for Heart and Lung Transplantation: Endorsed by the Heart Rhythm Society Circulation, September 20, 2005; 112(12): 1825 - 1852. [Full Text] [PDF] |
||||
![]() |
G. D. Buckberg Questions and answers about the STICH trial: A different perspective J. Thorac. Cardiovasc. Surg., August 1, 2005; 130(2): 245 - 249. [Full Text] [PDF] |
||||
![]() |
J. C. Walker, M. B. Ratcliffe, P. Zhang, A. W. Wallace, B. Fata, E. W. Hsu, D. Saloner, and J. M. Guccione MRI-based finite-element analysis of left ventricular aneurysm Am J Physiol Heart Circ Physiol, August 1, 2005; 289(2): H692 - H700. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Mancini and D. Burkhoff Mechanical Device-Based Methods of Managing and Treating Heart Failure Circulation, July 19, 2005; 112(3): 438 - 448. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Menicanti and M. Di Donato Left ventricular aneurysm/reshaping techniques MMCTS, April 25, 2005; 2005(0425): 596. |