Spoor
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. Nontransplant Surgical Options for Heart Failure.
Cohn Lh, ed. Cardiac Surgery in the Adult. New York: McGraw-Hill, 2008:1639-1648.
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CHAPTER 69 |
Congestive heart failure (CHF) has become a major worldwide public health problem. In our ever-aging population, medical advances that have extended our average life expectancy have also left more people living with chronic cardiac disease than ever before. In the United States alone there are nearly 4.9 million suffering with heart failure, yet of the 500,000 new patients diagnosed each year, less than 3000 are offered transplantation due to limitations of age, comorbid conditions, and donor availability. Despite the significant improvements in medical management, CHF patients are repeatedly readmitted for inpatient care and the vast majority will die within 3 years of diagnosis.1
The successful and reproducible long-term results with orthotopic heart transplantation (OHT) have made it the treatment of choice for patients with medically refractory endstage heart failure.2 Unfortunately, the obvious limitations to OHT include the need for immunosuppression and the severe shortage of donor organs. This past decade has seen the annual number of transplants performed worldwide plateau at less than 4000.3 This lack of donor availability has thus necessitated that rigorous selection criteria be applied to potential recipients in order to optimize the utility of these precious organs, indicated only for patients with endstage cardiomyopathy in whom all other modes of therapy have been exhausted. Access to OHT has thus been restricted to those without comorbid medical conditions and relatively restricted to those younger than age 65. This leaves the vast majority of CHF patients seeking other options.
Despite the technological strides being made toward total implantability, the role for mechanical support presently remains primarily as a bridge to transplantation or for temporary support. Though there have been a number of clearly successful cases of ventricular assist device (VAD) use as a bridge to recovery, its long-term efficacy for this purpose or its use as a long-term therapy for chronic heart failure remains to be fully evaluated by multicenter clinical trials.4–9 Though assist device technology may be on the verge of being implemented as a destination therapy for CHF, its current primary indication as a bridge to transplantation results in the restriction of its use to patients fulfilling candidacy for OHT. These confines, and the high cost associated with these devices, have yet to make the VAD an unrestricted surgical solution for the management of most CHF patients.
This clinical dilemma has provided the impetus for surgeons to develop new alternatives for the treatment of heart failure. As OHT and VAD use is more stringently applied, techniques to restore myocardial perfusion, eliminate valvular regurgitation, and restore ventricular geometry have emerged as the first-line surgical approach to heart failure. In response to the growing need for the proficient application and critical appraisal of the expanding menu of surgical options, the new subspecialty of heart failure surgery has emerged. The following will briefly review established nontransplant surgical modalities for heart failure such as coronary revascularization, geometric mitral reconstruction, and geometric ventricular reconstruction. Alternative options such as partial left ventriculectomy and cardiomyoplasty as well as some innovative devices currently being evaluated for clinical application will also be discussed.
We have known for nearly 20 years that revascularizing patients with left ventricular dysfunction can result in upwards of a 25% improvement in long-term survival.10,11 Early enthusiasm was tempered by reports of high operative mortality in patients with a low ejection fraction (EF). Since then, as success with the medical and surgical management of heart failure and transplantation grew, so did the interest in applying this experience to patients with ischemic cardiomyopathy. Successful revascularization can now be performed on patients with an EF less than 30% with hospital mortalities as low as 5%.12–14
The premise behind the improvements in EF, long-term survival, and quality of life of these patients following coronary artery bypass grafting (CABG) is believed to be due to postoperative myocyte recruitment. Restoration of perfusion resuscitates dormant viable myocardium and serves to protect the previously functioning portions of the ventricle from further ischemic insults, arrhythmias, and infarction. In order to minimize morbidity, a multidisciplinary approach to the preoperative management of heart failure is essential. Patients ideally suited for CABG are those who are medically optimized, with or without angina, who have good distal coronary targets, functional hibernating myocardium identified preoperatively, and no evidence of right ventricular dysfunction.15 As experience in managing these patients increases, many surgeons have operated on patients with ejection fractions less than 10%, those requiring reoperation, and those with moderate elevations in pulmonary artery pressure. Nevertheless, patients with clear documentation of poor right ventricular EF, clinical right-sided congestive symptoms, or fixed pulmonary hypertension above 60 mm Hg systolic should be approached cautiously, because these patients may in fact be better suited for transplantation.
The process of preoperative investigation should coincide with optimizing the patient’s medical management. This should entail an aggressive regimen of diuretic and vasodilator therapy to minimize ventricular afterload and normalize the patient’s circulating volume. For patients with severe heart failure, a brief period of inotropic therapy for ventricular resuscitation may be necessary to optimize their medical management. Inability to be weaned from this support is often indicative of severe myocardial injury and poor overall prognosis with any surgical therapy other than mechanical ventricular assistance or transplantation.
Preoperative investigations should begin with transthoracic echocardiography to grossly evaluate ventricular function and identify any underlying valvular pathology. Baseline screening physiologic studies of oxygen consumption, pulmonary function, and cardiopulmonary endurance are recommended. Identification of reversible ischemia by means of a nuclear study can be helpful; however, for patients with angina, many centers will proceed directly to coronary angiography. Though angina may be indicative of living ventricular muscle, perhaps the most important correlate of successful surgical recovery is the quantification of myocardial viability. Not only is a determination of myocardial contractile reserve essential to ensure that the patient can be safely separated from cardiopulmonary bypass, this information is predictive of ventricular recovery and long-term survival after operation. Though thallium-201 perfusion scans may distinguish myocytes with membrane integrity from scar, positron emission tomography scanning and dobutamine stress echocardiography permit the preoperative identification of myocardial viability and the prediction of postoperative function.16–18
The fundamental premise behind a successful operation is to attain an expeditiously performed and yet complete revascularization. As the failing myocardium is particularly intolerant to further episodes of ischemia, careful consideration should be given to the quality of the distal vessels and the ease with which good anastomoses can be achieved. Operative time expended grafting small or extensively diseased vessels, or performing additional techniques such as endarterectomy, may be counterproductive. Since the price to pay for incomplete revascularization or transient ischemia may be severe, off-pump techniques may not be ideally suited for these patients unless performed flawlessly.
Multiple groups have been uniformly successful in demonstrating improvements in survival, ventricular function, and functional status with coronary revascularization in patients with ischemic cardiomyopathy with ejection fractions less than 25%.19–21
The 5-year survival with transplantation ranges from 62 to 82%, whereas with medical therapy alone, it is less than 20%. Most series report survival following CABG for ischemic cardiomyopathy ranging from 85 to 88% at 1 year, 75 to 82% at 2 years, 68 to 80% at 3 years, and 60 to 80% at 5 years. Operative mortality has been reported from 3 to 12%, with the main predictor of increased risk being urgency of operation. When compared to medical therapy, revascularized patients have significant improvements in quality of life. Most series consistently report considerable enhancements in patient mobility, peak oxygen consumption, and functional status. The average preoperative New York Heart Association (NYHA) class of 3.5 reportedly drops to 1.5 after revascularization. Postoperatively, there are substantial reductions in readmissions for CHF and many patients return to work.
It is encouraging to note that the long-term survival of CHF patients following CABG is equivalent to transplantation in many series. The superior survival of CABG over transplant in the first 2 years postoperatively may be due to early attrition from rejection or infection in the latter group. Although there has been little reported on patients with ejection fractions under 10%, from the above data, one could infer that these patients would have a similarly better outcome than their nonrevascularized counterparts. As experience with heart failure surgery expands, refinements in preoperative and operative management of CABG patients will no doubt be reflected in the uniformity of future long-term results.
GEOMETRIC MITRAL RECONSTRUCTION
Functional mitral regurgitation (MR) is a significant complication of endstage cardiomyopathy and it may affect almost all heart failure patients as a preterminal or terminal event. Its presence in these patients is associated with progressive ventricular dilatation, an escalation of CHF symptomatology, and significant reductions in long-term survival, which is estimated to be between only 6 and 24 months.22
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In treating heart failure patients, the most significant determinant of leaflet coaptation and MR is the diameter of the mitral valve annulus. The left ventricular dimension is of less importance in functional MR, as the lengths of the chordae and papillary muscles are similar in myopathic hearts regardless of the presence of MR. Observations with medically managed patients with severe heart failure and MR reveal that decreasing filling pressure and systemic vascular resistance lead to reductions in the dynamic MR associated with their heart failure.33 This is attributed to a reduction in mitral orifice area relating to decreased left ventricular volume and decreased annular distention. This complex relationship between mitral annular area and leaflet coaptation may thus explain why an undersized "valvular" repair may help a "ventricular" problem. This restoration of the mitral apparatus and ventricle forms the premise behind geometric mitral reconstruction (GMR) for the treatment of heart failure (Fig. 69-3).
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30% received an undersized complete mitral annuloplasty ring as their mitral valve replacement procedure. Of these, 170 patients had a flexible complete ring while the remaining patients received a nonflexible undersized complete ring. In follow-up, 16 flexible ring patients (9.4%) required a repeat procedure for significant recurrent geometric MR and CHF (10 replacements, 3 re-repairs, and 3 transplants). The average time to reoperation was 2.4 years. In contrast, 119 patients with an EF 30% received a mitral valve replacement using an undersized nonflexible complete ring. Only 3 nonflexible patients required a repeat operation, 1 a mitral valve replacement and 2 patients required a transplant. The time to reoperation was 4.0 years. There was a significant difference in reoperation rates for recurrent MR between the two groups (p = 0.012). There were no differences between groups in terms of age, ring size used, preoperative EF, left ventricular size, MR grade, or NYHA class.34 All patients were in NYHA class III or IV heart failure despite receiving maximal medical therapy. On immediate postoperative echocardiograms, the mean transmitral gradient was 3 ± 1 mm Hg (range 2 to 6 mm Hg). The overall operative mortality has been under 5%. There have been 27 late deaths: 12 from sudden ventricular arrhythmias, 9 from progression of CHF but without MR, 3 related to complications from other operative procedures, 2 that progressed to transplantation, and 1 suicide. The 1-, 2-, 3-, and 5-year actuarial survivals following GMR are 82%, 71%, 68%, and 57% respectively.
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The technique of undersizing in mitral reconstruction avoids systolic anterior motion in these myopathic patients, likely due to widening of the aorto-mitral angle in these hearts with increased left ventricular size. Furthermore, acute remodeling of the base of the heart with this reparative technique may also reestablish the somewhat normal geometry and ellipsoid shape of the left ventricle. As evidenced by the decreased sphericity index and left ventricular volumes seen in these patients, the geometric restoration from mitral reconstruction not only effectively corrects MR, but also achieves surgical unloading of the ventricle.
Many centers have reported similar consistent findings following GMR.35–39 With outcomes equating to those of transplant while avoiding immunosuppression, this straightforward reparative operation performed in conjunction with medical management may be offered to all patients with MR and cardiomyopathy as a first-line therapy.
GEOMETRIC VENTRICULAR RECONSTRUCTION
Myocardial revascularization and GMR reliably improve ventricular function. However, further surgical techniques have been developed that attempt to augment left ventricular function through a reduction of end-diastolic wall tension following the principles of the law of Laplace. Since ventricular wall tension is directly proportional to left ventricular radius and pressure and inversely proportional to wall thickness, any intervention to optimize this relationship would be beneficial. As heart failure progresses, so does the progressive thinning and dilatation of the left ventricle, thus leading to increasing wall stress and further dilatation. This remodeling process may result in regional left ventricular dysfunction, as occurs following segmental myocardial infarction, or global left ventricular dysfunction, which may arise from either ischemic or nonischemic etiologies. The concept of reducing wall stress through the surgical restoration of left ventricular cavity size and geometry remains the guiding principle behind many innovative techniques including those developed for the isolation of left ventricular aneurysms and nonfunctioning ventricular segments.
After an acute myocardial infarction, the noncontractile myocardium undergoes thinning and fibrous replacement often following the segmental distribution of the arterial occlusion. This nonfunctional left ventricular segment may remain akinetic or transform into a dyskinetic aneurysm, depending on factors such as age and regional collateral circulation. Though such postinfarct pathologic remodeling may occur in any area of the heart, the most common clinically relevant region that manifests is the anteroapical segment of the left ventricle. The resulting loss of contractile function in the affected segment results in global increases in left ventricular wall tension and myocardial oxygen consumption, in turn leading to compensatory left ventricular dilatation in accordance with the law of Laplace. These geometric ventricular changes may also result in loss of the zone of coaptation and MR following infarction, as discussed earlier. Moreover, when a dyskinetic region expands and becomes aneurysmal, cardiac work is further increased due to the paradoxical systolic motion of the thinned segment. These pathologic alterations often result in CHF. The principle of surgical restoration of left ventricular geometry involves the isolation of these nonfunctional areas and a subsequent reduction in left ventricular volumes. This concept has been clearly illustrated by Dor and others, who have revealed significant improvement in heart failure after endoventricular patch exclusion of dyskinetic or akinetic ventricular segments.40–43
The preoperative selection and preparation for left ventricular reconstruction should follow the identical medical optimization discussed earlier. In addition to viability assessment, echocardiography, and contrast ventriculography, cardiac MRI and left ventricle–gated nuclear imaging have proved valuable tools for pre- and postoperative volume estimation and anatomic assessment of the left ventricular wall and septum. The pre- and intraoperative decision on when to perform left ventricular reconstruction should be based on the function, viability, and thinning of the segment, as well as the location of viability-targeted concomitant coronary grafting. Benefits obtained from repairing dyskinetic thin aneurysmal defects are well established.40,42 More recently, however, preliminary reports have revealed encouraging results with endoventricular repair of nondilated akinetic segments when combined with CABG. These findings have spawned the multicenter Surgical Treatment of Ischemic Heart Failure (STICH) trial to evaluate its long-term functional benefit.
The operative principles of left ventricular reconstruction involve optimal myocardial preservation, septal exclusion of the nonfunctioning segment with an endoventricular patch, and closure of the excluded ventricular myocardium. To improve the visual and tactile identification of the nonfunctioning segment, the ventricular repair is often performed on the perfused beating unvented heart decompressed with cardiopulmonary bypass. Entry should be at least 1 to 2 cm to the left of the anterior descending coronary artery to avoid the septum. The thinned segment often will pucker when the left ventricle is decompressed, thus marking the initial access point. A point knife is used to gain entry to permit complete decompression and endocardial visualization under direct vision as the incision is further developed. This allows for the safe removal of any left ventricular thrombus if present, as well as for the visual and tactile identification of the septum and demarcation zone between functioning and nonfunctioning myocardium. A circumferential monofilament suture or "Fontan stitch" is then placed within this zone and tied as advocated by Dor. The resulting reduced size of the defect is then patched with bovine pericardium and the residual myocardial defect is buttressed closed with strips of bovine pericardium or felt. Though concomitant GMR and CABG can be performed before or after left ventricular reconstruction, it is often advocated before, so as to allow for improved myocardial recovery and reperfusion following removal of the aortic cross-clamp.
Results from left ventricular reconstruction have been favorable and consistent between groups regardless of whether endoventricular circular patch plasty or a modified linear patch closure technique is utilized. Significant reductions in left ventricular end-systolic volume index and improvements in EF, NYHA class, and long-term survival have resulted. It is being regularly performed with hospital mortalities of under 8% and with a 12-month freedom from readmission for CHF of over 80%.40,42–46 Therefore, geometric left ventricular reconstruction by endoventricular exclusion of nonfunctional segments should be placed alongside high-risk CABG and GMR as a first-line surgical option for heart failure.
Batista has furthered the concept of surgical ventricular remodeling to optimize wall tension in dilated ventricles with the contention that all mammalian hearts should share the same mass-diameter ratio regardless of size. He proposes that all hearts not complying with this relationship should have a segment of the left ventricular wall excised in order to diminish mural tension and improve myocardial oxygen consumption in accordance with the law of Laplace.47,48 This interesting concept was initially presented as a case report of a 34-year-old patient who underwent a partial left ventriculectomy (PLV) that reportedly increased the EF from 17 to 44% at 2 months postoperatively. Batista performed over 150 such procedures predominantly on patients with Chagas disease and dilated cardiomyopathy. Though this experience stimulated much interest, unfortunately no meaningful follow-up data or statistical analyses have ever been made available from this series.
To further evaluate the potential benefits of PLV, the Cleveland Clinic performed 62 such cases on patients with idiopathic dilated cardiomyopathy awaiting transplant. The ventriculectomy involved resection of the lateral wall of the left ventricle in the circumflex coronary artery distribution to the base of the papillary muscles with closure between two strips of felt or bovine pericardium. This was one of the largest North American series, reporting a 3.5% operative mortality with 7 late deaths and a 1-year actuarial survival of 82%. However, of the total 62 patients, 24 (39%) were considered short-term treatment failures: 11 required left VAD support, 6 were listed for transplantation again, and 7 non-left-VAD patients died.48 Moreover, a further 30% attrition rate at 2 years following PLV has been reported.49,50 These results may be superior to no surgical treatment, but they fall short of those obtained by other surgical options for heart failure. As a result, PLV has fallen into disfavor in North America. However, in the Asian-Pacific region, where transplantation is not widely available, efforts by Suma and associates to improve selection criteria and introduce echo-guided surgical decision making have resulted in PLV persisting as a viable option for heart failure in this part of the world.51
In attempting to elucidate the mechanism behind the relative success of PLV, it is quite interesting to note that over 95% of the cases performed in the Cleveland Clinic experience also involved a mitral reconstruction. Therefore, it becomes difficult to discern the role mitral repair plays in the overall utility of PLV, since patients undergoing mitral reconstruction alone also attain normalization of the left ventricular mass-to-volume ratio, but without the excision of viable myocardium.26 Furthermore, experimental models of heart failure have revealed that correction of the MR alone permits left ventricular remodeling that may be rapid and complete, with resulting regurgitant fractions of less than 30%.52
Though the concept of instantly remodeling the left ventricle through PLV is mechanically appealing, discarding functioning myocardium is not. Patients with ischemic cardiomyopathy with a dyskinetic aneurysmal segment have undergone successful remodeling with an endoventricular patch repair. Patients with dilated cardiomyopathy and MR have undergone mitral reconstruction thereby altering the angulation of the base of the heart and promoting favorable left ventricular geometry and remodeling. Thus, at this time, when similar if not superior results can be obtained by methods that preserve myocardial integrity, the application of PLV to patients with endstage heart failure should be approached with an element of caution.
Another alternative method to surgically optimize Laplace’s law is dynamic cardiomyoplasty (DCMP) using the patient’s own skeletal muscle wrapped around the heart to help reduce wall stress and provide limited cardiac assistance. The latissimus dorsi muscle is wrapped around the failing heart, and by means of an implantable cardiomyostimulator, the muscle is stimulated to contract in synchrony with cardiac systole.
Starting in 1985, Medtronic Inc. began coordinating a multicenter Food and Drug Administration trial to evaluate the cardiomyostimulator. Pooled observations after DCMP reveal a paucity of positive quantitative hemodynamic or survival data, yet paradoxically, patients report over 30% functional improvement when compared to medical therapy alone.53,54
Though DCMP is now only rarely performed in North America, the recently available LD Pace myostimulator out of Russia has allowed this procedure to continue to be available in that country as well as throughout various centers in Europe, Asia, and the Caribbean.
Investigations into the mechanisms of DCMP have generated spinoffs in the fields of myoblast transplantation and remodeling surgery. Studies revealed that the wrap actually contributes to significant reductions in myocardial wall stress.55 In effect, this conceptually protects myocytes from overt functional stresses and thereby prevents the adaptive progressive dilatation of heart failure. Working in favor of the law of Laplace, this girdling effect of DCMP was seen with unstimulated adynamic cardiomyoplasty. Original experiments comparing adynamic cardiomyoplasty to synthetic material revealed that this beneficial girdling effect even occurs when a passive constraint of prosthetic mesh fabric is applied to the ventricles, and they have spawned the development of novel biomedical devices currently under clinical investigation.56
EMERGING BIOMEDICAL DEVICES FOR HEART FAILURE
The Acorn Cardiac Support Device (ACSD; Acorn Medical, Minneapolis, Minn) is a polyester mesh fabric that attempts to reduce ventricular wall stress by providing external support. Much like DCMP, the ACSD is placed around the ventricles from posterior to anterior, using stay sutures as well as an anterior fabric seam for snug tailoring to the patient’s heart.
Taking advantage of the girdling effect, the purpose of this device is to passively support the failing ventricles and prevent further dilatation. Preclinical data have shown decreased left ventricular volumes and improvements in regional wall motion, EF, and other functional parameters without any evidence of constrictive physiology.57 Histologic animal studies have also demonstrated decreased myocyte hypertrophy and interstitial fibrosis, as well as improvements in several biochemical markers of failure.58,59 A phase I and II clinical trial has been completed to assess the safety and the early remodeling ability of the ACSD when used on heart failure patients with or without concomitant cardiac procedures. While not currently approved by the Food and Drug Administration for general use, the device continues to remain under current investigation. Preliminary experience reveals that the ACSD is easily applied, and may even be performed without the necessity of cardiopulmonary bypass.
The Myocor Myosplint (Myocor Medical, St. Paul, Minn) is a second device developed to reduce ventricular wall stress by directly altering cardiac geometry. Working on the premise of optimizing the law of Laplace, it involves the placement of transventricular tension bands through the right ventricular and left ventricular walls that have the unique ability to be individually tightened in order to achieve a 20% reduction in wall stress. Preclinical animal data have shown improvements in end-diastolic volume, end-systolic volume, and EF. These experiments reveal that the Myocor device becomes readily incorporated within a fibrous capsule that has been free of thrombus formation. A phase I clinical trial is underway to assess device safety in patients prior to cardiectomy at the time of transplant. Preliminary data reveal that the device can be readily deployed without harm to other cardiac structures. Further chronic studies are required to address the efficacy of this unique device.
The Geoform mitral valve annuloplasty ring (Edwards Lifesciences, Irvine, Calif) has a three-dimensional shape that attempts to combine the previously discussed principles of mitral valve repair and geometric remodeling of the left ventricle into the next generation of mitral valve rings (Figs. 69-5 and 69-6). This ring attempts to change and promote remodeling of the left ventricle through alterations in the mitral valve apparatus. The basic anatomic problem in dilated left ventricles, whether from ischemia or not, is the tendency of the posterior mitral valve annulus to fall away from the annular plane, which further promotes increased mitral regurgitation and increased left ventricular wall stress. Restoring the zone of coaptation of the mitral valve using this ring in the normal plane has two combined effects, of correcting the mitral regurgitation and changing the shape of the left ventricle (Fig. 69-7). Based on the elegant and pioneering efforts of Alfieri’s group, the new geometry of the ventricle following this procedure has lower wall stress, which should promote further beneficial changes in the ventricle over time as the volume overload is relieved following correction of the mitral regurgitation60 (Fig. 69-8). The Geoform ring is currently approved for clinical use with multiple implants performed at several centers worldwide.
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The Edwards Milano II mitral clip (Edwards Lifesciences, Irvine, Calif) and Evalve Mitraclip system (Evalve Inc., Menlo Park, Calif) use a catheter-based approach to deliver a clip to both the anterior and posterior mitral valve leaflets using the principles of mitral repair pioneered by Dr. Otavio Alfieri. Percutaneous catheters are introduced via the femoral vein and cross the atrial septum to enter the left atrium similar to a percutaneous mitral balloon annuloplasty approach. A catheter-based clip is then used to create a permanent coaptation point between the leading free edges of the anterior and posterior mitral leaflets. This technology is in the investigational stage with the Evalve clip currently being evaluated in the phase II EVEREST trial.
The Viacor percutaneous mitral annuloplasty system (Viacor Inc., Wilmington, Mass), Edwards Viking percutaneous mitral annuloplasty system (Viking, Edwards Lifesciences Inc., Irvine, Calif), and Carillon mitral contour system (Cardiac Dimensions, Kirkland, Wash) all use an emerging technology approach to mitral annuloplasty using a catheter-based approach to the mitral valve. Using percutaneous catheters, a permanent nitinol strut is placed into the coronary sinus that wraps around the posterior annulus of the mitral valve and attempts to indirectly influence the action of the posterior mitral valve leaflet similarly to a partial ring annuloplasty by reducing the anterior-posterior dimension of the mitral annulus. The devices are presently under investigational study and are not currently approved for routine use.
As surgical therapies for heart failure rapidly evolve, the need for their critical appraisal is essential so that they may be offered to the growing population of CHF patients in a prompt yet effective manner. Transplantation continues to offer selected patients reliable long-term survival in a reproducible fashion, and it thus remains the gold standard surgical therapy for heart failure. Though in time we may see mechanical assist devices play a more prevalent role in myocardial recovery or destination therapy, currently their main utility is as a bridge to transplantation. With the growing disparity between donor availability and heart failure patients, experience is mounting with effective nontransplant surgical solutions.
The results of the more conventional techniques of CABG, geometric mitral reconstruction, and ventricular reconstruction, when combined with the optimal medical management of heart failure may now be on a par with transplantation. Therefore, these modalities now form the new first-line surgical therapy for heart failure when applicable. Patients with primary ischemic cardiomyopathy with favorable anatomy may be effectively managed with revascularization alone or in combination with left ventricular reconstruction. Myopathic patients with MR, regardless of etiology, may be effectively managed with mitral reconstruction. With the superior results of these approaches, the use of other techniques such as PLV and DCMP should be reserved as viable alternative surgical options for heart failure. The prudent and effective application of the growing menu of surgical strategies for heart failure enables the scarcely available donor hearts to be efficiently used for patients with truly no other surgical or medical alternatives. Along with the utility of emerging biomedical devices, each of these unique modalities has enhanced the clinically effective armamentarium of the modern surgeon treating patients with heart failure.
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