Partial left ventriculectomy in patients with dialated failing ventricle

Ventricular reshaping with a beating heart implant improves pump function in experimental heart failure

OBJECTIVE

The left ventricle remodels from an ellipsoidal/conical shape to a spherical shape after a myocardial infarction. The spherical ventricle is inefficient as a pumping chamber, has higher wall stresses, and can lead to congestive heart failure. We sought to investigate if restoring physiological ventricular shape with a beating heart implant improves pump function.

METHODS

Rats were induced with a myocardial infarction, developing left ventricular dilatation and dysfunction, and becoming spherical over 3 weeks. Thereafter, they were randomized to undergo left ventricular reshaping with a beating heart implant (n = 19) or continue follow-up without an implant (n = 19). Biweekly echocardiography was performed until 12 weeks, with half the rats euthanized at 6 weeks and remaining at 12 weeks. At termination, invasive hemodynamic parameters and histopathology were performed.

RESULTS

At 3 weeks after the infarction, rats had a 22% fall in ejection fraction, 31% rise in end diastolic volume, and 23% rise in sphericity. Transventricular implant reshaping reduced the volume by 12.6% and sphericity by 21%, restoring physiologic ventricular shape and wall stress. Over the 12-week follow-up, pump function improved significantly with better ventricular-vascular coupling in the reshaped hearts. In this group, cardiomyocyte cross-section area was higher and the cells were less elongated.

CONCLUSIONS

Reshaping a postinfarction, failing left ventricle to restore its physiological conical shape significantly improves long-term pump function.

Left ventricular volume reduction surgery: The 4th International Registry Report 2004

BACKGROUND AND METHODS

An international registry of left ventricular volume reduction (LVVR) procedures, including partial left ventriculectomy, has been expanded, updated, and refined to include 568 cases voluntarily reported from 52 hospitals in 12 countries.

RESULTS

Gender, age, ventricular dimension, ethnology, myocardial mass, presence or absence of mitral regurgitation, as well as transplant indication, had little effect on event-free survival, which was defined as either absence of death or ventricular failure requiring mechanical assist or transplantation. Poor preoperative patient condition such as New York Heart Association classification IV, depressed contractility and decompensation requiring an emergency procedure were associated with reduced event-free survival. Other risk factors included an early surgery date, lack of experience, dilated cardiomyopathy as the underlying pathology and extended myocardial resection. Performance of LVVR reached a peak by 1998, but was largely abandoned by 2001, except in Asia, where experienced institutes continue to perform it in patients in better condition with preserved myocardial contractility.

CONCLUSION

Avoidance of risk factors appears to have contributed to the recent survival improvement and may help stratify patients for LVVR. While performance has been decreasing, the concept has been extended to other LVVR and less invasive procedures, which are now under clinical trials.

Partial left ventriculectomy in elderly patients not suitable for heart transplantation

BACKGROUND

Although donor scarcity and intolerance to immunosuppression tend to exclude elderly patients from transplantation, partial left ventriculectomy (PLV) has been performed without bias against advanced age.

METHODS

Among 392 patients undergoing PLV, 61 elderly patients aged 65 or older (> or =65) were compared with the rest of the patients in terms of underlying disease, postoperative course, and survival time.

RESULTS

The aged patients (> or =65) compared to younger patients (<65), had ischemic disease (37.7% vs. 19.3%, p < 0.05) more frequently than cardiomyopathy (34.4% vs. 43.2%) or valvular disease (23.9% vs. 16.4%) and underwent lateral PLV (74% vs. 79%) more frequently than extended PLV (26% vs. 21%). Although the elderly patients required coronary bypass grafting more frequently (39.3% vs.17.2%, p < 0.05), surgical complexity was similar in terms of bypass time (63 minutes vs. 63 minutes) and percentage requiring cardiac arrest (31% vs. 44%). Despite advanced age, they required comparable ICU care (6.6 days vs. 5.4 days) and postoperative hospital stay (12 days vs. 11 days), resulting in a low but similar hospital survival (57% vs. 62%) and functional capacity after discharge (NYHA class 1.5 vs. 1.4).

CONCLUSION

The results suggest that PLV can be performed in elderly patients (> or =65 years) with comparable risks and benefits with the younger patients, promoting its application in patients disqualified for heart transplantation because of age criteria.

Ventricular volume reduction procedures

Although partial left ventriculectomy (PLV) has been abandoned in many institutions, a few hospitals continue to perform it with a relatively favorable outcome. Other volume reduction procedures have become popular with renewed interest in ventricular reshaping to improve function. Although recent refined selection criteria have improved survival with PLV, earlier unpredictable results prompted less invasive procedures based on the same physiologic concept of reducing radius or wall tension by wrapping, piercing, or clasping. These new techniques are not only less invasive but also reversible and adjustable and appear safer for less symptomatic patients at risk of progressive heart failure. Nonetheless, mechanisms of action and degrees of volume reduction and/or restriction need to be delineated before widespread clinical application.

Partial left ventriculectomy--The Third International Registry Report 2002

BACKGROUND

An international registry of partial left ventriculectomy (PLV) has been expanded, updated, and refined to include 440 cases voluntarily reported from 51 hospitals in 11 countries.

RESULTS

Gender, age, ventricular dimension, etiology, ethnology, myocardial mass, operative variation or presence or absence of mitral regurgitation as well as transplant indication had no effects on event-free survival, which was defined as either absence of death or ventricular failure requiring ventricular assist device or listing for transplantation. Preoperative patient condition such as NYHA functional class IV, depressed contractility, and decompensation requiring an emergency procedure were associated with reduced event-free survival. Other risk factors included early date of surgery, lack of experience, and extended myocardial resection. Performance of PLV reached a peak by 1998 and was largely abandoned by 2000 except in Asia, where experienced institutes continue to perform PLV in patients in better condition with preserved myocardial contractility.

CONCLUSION

Avoidance of delineated risk factors appears to improve recent survival and may help stratify high- or low-risk patients for PLV. An integrated approach with mechanical and biological circulatory assist may improve prognosis for patients with dilated failing hearts. While frequency of PLV has decreased, the concept of ventricular volume reduction has been extended to other volume reduction procedures and less invasive procedures now under clinical trial.

Factors affecting ventricular function and survival after partial left ventriculectomy

BACKGROUND

Partial left ventriculectomy (PLV) helps some patients but is deleterious in others. Selection of patients who will benefit from PLV, and exclusion of those who will not is necessary for safe and effective application of the procedure.

METHODS

Sixty-nine consecutive patients who underwent PLV were monitored with pressure-volume relationship analyses, Doppler echocardiography, and histopathologic studies of excised myocardium. These parameters were correlated with postoperative stroke volume (SV, ml), cardiac output (CO, L/min), ventricular function (improved, no change, or deteriorated), and postoperative course (duration of survival and/or hospital discharge).

RESULTS

Positive responders (n = 36) with increased SV at reduced end diastolic pressure had significantly larger preoperative end-systolic dimension, smaller SV, and less stroke work with milder fibrosis than non- or negative responders (n = 33). In multivariate analyses, poor preoperative hemodynamics were associated with increased SV and CO, but these improvements did not lead to improved survival. Postoperative survival was negatively affected by larger preoperative left ventricular end-diastolic volume and larger excised-muscle-weight. Milder fibrosis and thicker excised wall were consistently related to improved ventricular function and survival.

CONCLUSION

Although effects of PLV are related to preoperative status, factors affecting postoperative ventricular function and survival were often discordant. While poor preoperative ventricular function was associated with functional improvement without survival benefit, milder fibrosis, thicker excised wall and less myocardial resection were positive contributors to improved ventricular function, discharge, and survival. Preoperative evaluation with more cases and variables are needed to identify patients more likely to benefit from PLV.

Does repair of mitral regurgitation eliminate the need for left ventricular volume reduction?

BACKGROUND

Effects of partial left ventriculectomy (PLV) remain ill-defined because mitral regurgitation (MR) repair by isolated annuloplasty alone has been reported to improve patients with dilated left ventricle and severe MR.

METHODS

Among patients undergoing PLV, 120 had paired pre- and postoperative (<1 week) Doppler echocardiograms. Effects of preoperative MR were studied by comparing 45 patients with no preoperative MR (MR-) and 75 patients with significant MR (MR+; MR = 1.51 when MR is enumerated as none = 0, mild = 1, moderate = 2).

RESULTS

MR- patients as compared with the MR+ group were older (53.8 vs. 49.2 years, P = 0.047), had less frequent dilated cardiomyopathy (33.3% vs 49.3%,P <0.01), similar ventricular dimension (72.3 mm vs 73.0 mm), septal thickness (9.5 mm vs 9.6 mm), posterior wall, fractional shortening (15.9% vs 16.8%) and ventricular mass (330 g vs 345 g), resulting in comparably reduced functional capacity (NYHA 3.40 vs 3.67). Although the MR- group required significantly less frequent mitral procedure (64.4% vs 84.0%, P < 0.01) and shorter cardiac arrest time, they had similar postoperative MR (0.22 vs 0.39), highly significant parallel reduction in ventricular dimension (P < 0.001 in either group), and improved %FS (P <0.001 in either group), resulting in similar hospital survival (87.1% vs 86.4%) and 90-day survival (71.1% vs 78.7%) with significantly comparable improvement in functional class (P = 0.011 in both groups). Histological severity of interstitial fibrosis (P = 0.80), weight (P = 0.93), and thickness (P = 0.76) of excised myocardium was comparable between the two groups.

CONCLUSION

Patients with no preoperative MR were found to benefit from PLV as did patients with significant MR. Beneficial effects of PLV appeared to derive mainly from volume reduction rather than abolished MR in this study.

Long-term results after partial left ventriculectomy

BACKGROUND

Long-term clinical, echocardiographic and hemodynamic effects after partial left ventriculectomy (PLV) and predictors of outcome have been determined.

METHODS

Between January 1995 and July 1999, PLV was performed in 39 patients. In 15 patients the etiology of heart failure was idiopathic dilated cardiomyopathy (DCMP), 19 patients had ischemic cardiomyopathy (ICMP) and five patients had valvular cardiomyopathy. Concomitant procedures included coronary artery bypass grafting in 16 patients, mitral valve repair in 33 patients and aortic valve replacement in five patients. All patients belonged in New York Heart Association (NYHA) functional class III or IV. Mean follow-up was 663+/-514 days. Clinical, echocardiographic and hemodynamic assessments and metabolic stress testing were performed preoperatively, within 30 days postoperatively and 6, 12 and 24 months after the operation.

RESULTS

Actuarial survival was 64% after 1 year, 55% after 2 years and 44% 3 years after the operation. In patients with ICMP as well as in patients with DCMP actuarial 1 year survival was 60%. At 2-year follow-up NYHA functional class was improved significantly (P<0.05), but LV ejection fraction, LV end-diastolic diameter, cardiac index and peak oxygen consumption did not differ significantly from preoperative values. Analysis of factors influencing postoperative outcome indicated that decreased left ventricular wall thickness and a failure to increase the stroke volume index as a response to preoperative dobutamine administration were associated with postoperative mortality.

CONCLUSIONS

PLV is associated with considerable postoperative mortality and lacking long-term improvement of cardiac performance.

Partial left ventriculectomy in association with dilated cardiomyopathy: echocardiographic follow-up

Left ventricular function after a left ventriculectomy was assessed in a patient with idiopathic dilated cardiomyopathy (DCM) who has survived longer than any other patient in Japan after this operation. The 19-year-old male had a history of cerebral infarction because of left ventricular thrombus associated with DCM. In order to remove the thrombus and improve left ventricular function, an approximately 12x4cm piece of myocardial tissue was resected according to the methods of Batista's operation. Left ventricular diastolic dimension was temporarily reduced 1 month after surgery, but increased again. During the 45 months of follow-up, left ventricular diastolic dimension, cardiac output and New York Heart Association functional class remain unchanged from the preoperative values.

Surgical alternatives for heart failure

Heart failure is one of the leading causes of hospitalization in the United States. Congestive heart failure is a chronic, progressive disease and its central element is remodeling of the cardiac chamber associated with ventricular dilation. Secondary mitral regurgitation is a complication of end-stage cardiomyopathy and is associated with poor prognosis. Historically, these patients were not considered operative candidates because of their high morbidity and mortality. Heart transplantation is now considered standard treatment for select patients with end-stage heart disease; however, it is applicable only to a small number of patients. In an effort to address this problem, newer and alternative surgical approaches are evolving, including mitral valve annuloplasty, the Batista procedure, and other left ventricular shape changing technologies. Using these operative techniques to alter the shape of the left ventricle, in combination with optimal medical management for heart failure, improves survival, and patients may avoid or postpone transplantation.

Transventricular mitral annuloplasty in a patient undergoing partial left ventriculectomy

A 70-year-old male patient with heart failure resulting from dilated cardiomyopathy underwent a partial left ventriculectomy between the papillary muscles and a newly devised transventricular mitral annuloplasty. Intraoperative transesophageal Doppler echocardiography revealed reduced ventricular dimensions and corrected mitral insufficiency with unchanged ventricular filling patterns, allowing prompt recovery despite unchanged myocardial pathology.

Partial left ventriculectomy for patients with ischemic cardiomyopathy

BACKGROUND

Partial left ventriculectomy (PLV) has been performed in patients with dilated cardiomyopathy (DCM), but improved myocardial energetics may make PLV useful also for ischemic cardiomyopathy (ICM) unamenable to conventional treatment.

METHODS

Of 262 patients undergoing PLV, 94 patients with ICM as the underlying pathology were analyzed and compared with 168 patients with DCM.

RESULTS

ICM patients were older (57.3 years vs 50.9 years, p = 0.0001) and heavier (69.7 kg vs 65.9 kg, p = 0.039) than those with DCM, but ventricular end-diastolic and end-systolic dimensions were similar with comparably depressed fractional shortening (16% vs 15%, p = 0.294) and equally severe functional limitation [New York Heart Association (NYHA) Class 3.7 vs 3.6, p = 0.734]. A majority of patients in both groups underwent lateral PLV (76% vs 74%, p = 0.883) with myocardium excised between papillary muscles and simultaneous mitral valvuloplasty (41% vs 74%, p < 0.0001). Because ICM patients required coronary artery bypass grafting (CABG) more frequently (79% vs 0.6%, p < 0.0001), operation was more extensive in terms of bypass time (74 minutes vs 47 minutes, p < 0.0001), percentage requiring cardiac arrest (43% vs 19%, p < 0.0001), and arrest duration (34 minutes vs 28 minutes, p = 0.280), but all had similar resection and postoperative ventricular dimensions. Nonetheless, ICM patients required shorter intensive care unit (ICU) time (4.4 days vs 5.9 days, p = 0.048) and similar postoperative hospital stays, resulting in similar hospital survival rates (69% vs 71%, p = 0.778) and functional capacity in long-term follow-up.

CONCLUSIONS

Results suggest that PLV can be performed in patients with ICM with comparable risks and benefits as in DCM. Relative efficacy of CABG and mitral repair as compared to volume reduction remains to be studied.

Mitral regurgitation after partial left ventriculectomy as the cause of ventricular redilatation

BACKGROUND

It remains unclear whether ventricular redilatation after partial left ventriculectomy (PLV) is due to underlying pathology or to continued volume overload amenable to surgery.

METHODS

Among patients undergoing PLV, 32 had Doppler echocardiography preoperatively, immediately after surgery (< 1 week), early after surgery (1-3 months), and late after surgery (8-14 months). Patients were divided into groups with mitral regurgitation (MR; MR+, n = 16) and without postoperative MR (MR-, n = 16) and were compared for ventricular size, performance, and survival.

RESULTS

After initial surgical reduction, left ventricular dimension on average gradually increased back to the preoperative level in subgroups of patients with valvular disease and cardiomyopathy and in all patients combined. Most patients showed drastically reduced left ventricular dimension early after PLV. In MR+ patients, dimension increased back to the preoperative level within 3 months after surgery, whereas the MR- group maintained reduced dimension throughout the first year in all patients combined and in a subgroup of patients with cardiomyopathy. Occurrence of significant MR after PLV appeared to be related to severity of fibrosis in excised myocardium but not to severity of preexisting MR, etiology, or performance of mitral valvuloplasty.

CONCLUSIONS

Early postoperative MR, residual or new, appeared to play an important role in dictating early hemodynamics and late outcome in patients undergoing PLV. Results suggest an aggressive simultaneous approach to abolish MR. Causative role of myocardial fibrosis remains unclear and needs further study.

Perioperative ventricular arrhythmias in patients undergoing partial left ventriculectomy

BACKGROUND

Although incidence of ventricular arrhythmias after partial left ventriculectomy (PLV) has been reported, there are no studies comparing incidence before and after PLV. Although operative scars may give rise to arrhythmias, improved energetic efficiency after PLV may decrease their incidence.

METHODS

Pre- and postoperative ventricular arrhythmias were monitored by Holter ECG and analyzed in 17 patients undergoing PLV in Curitiba, Brazil.

RESULTS

Although total 24-hour heart beat (THB) increased significantly (p = 0.018), ventricular premature contractions (VPCs) decreased markedly (p = 0.036), excluding one patient dying in low cardiac output (LOS) who had terminal arrhythmias increased multifold. In the remaining 16 patients, VPC pairs were also reduced significantly on the average (p = 0.038). In contrast, ventricular tachycardia (VT; more than three consecutive VPCs) disappeared in five patients, decreased in two patients, and newly occurred in four patients, with five patients showing no change; one of them developed a prolonged VT, successfully reversed by external cardioversion.

CONCLUSIONS

Despite notable significant increase in THB immediately after PLV, PVC and PVC pairs were significantly decreased in contrast to VT, which disappeared in some patients and newly occurred in other patients, remaining constant on the average. Sustained VT occurring in a patient with all other arrhythmias suppressed may suggest a unique electrophysiological substrate, may justify prophylactic use of amiodarone or an implantable cardioverter-defibrillator, and may underscore the importance of further and extended studies.

Partial left ventriculectomy. The First Japanese Registry Report 1999

OBJECTIVE

Partial left ventriculectomy has been performed without standardized inclusion/exclusion criteria. A registry has been established to accumulate experience with this procedure to identify indications, risks and benefits.

METHODS

In response to a mailed inquiry, 90 cases were voluntarily registered from 28 Japanese institutions.

RESULTS

Males (n = 67, 74.4%) predominated, and 29 (32.2%) patients were over 60 years old. The underlying cardiac pathologies included dilated cardiomyopathy (n = 75, 83.3%), valvular disease (n = 8, 8.9%), the dilated phase of hypertrophic cardiomyopathy (n = 4, 4.5%), and others (n = 3, 3.3%). Gender, age, etiology, papillary muscle excision and absent transplant indication did not significantly affect survival. Poorer preoperative condition, reduced contraction and decompensation necessitating emergency operation were each associated with a significantly higher risk. Hospitals performing less than 5 cases had poorer results than more experienced institutions (p = .0019), which showed a tendency towards improved survival in the second half of their experience (p = .096). Hospital mortality (n = 29, 32.6%) and late death (n = 10, 11.2%) were mainly from ventricular failure with few sudden deaths over a period of 63.6 patient years follow-up. Late mortality was equally distributed in the first year and leveled off with significantly improved cardiac functional class in survivors.

CONCLUSION

Partial left ventriculectomy was associated with better survival in less symptomatic patients with better contractile reserve undergoing an elective operation preserving the papillary muscles. Avoidance of identified risk factors may allow better patient selection and improved survival in the current environment where rescue transplantation is not readily available. Long-term follow-up is warranted with more registry data.

Improved left ventricular contraction and energetics in a patient with Chagas' disease undergoing partial left ventriculectomy

A 43-year-old patient with heart failure, precluded from heart transplantation or dynamic cardiomyoplasty because of Chagas' disease cardiomyopathy, mitral regurgitation, and ventricular mural thrombi, underwent mitral valvuloplasty and partial left ventriculectomy (PLV) between the papillary muscles. Intraoperative pressure-volume relationship analyses suggested improvement in left ventricular contraction, energetics, isovolumic relaxation, and mitral valve competency. These improvements allowed prompt, short-term recovery despite unchanged myocardial pathology, which suggests that a surgical approach can alter anatomic-geometric factors and achieve clinical improvement in a dilated failing ventricle.

Partial left ventriculectomy: the 2nd International Registry Report 2000

BACKGROUND

Partial left ventriculectomy (PLV) has been performed without standardized inclusion or exclusion criteria.

METHODS

An international registry of PLV was expanded, updated, and refined to include 287 nonischemic cases voluntarily reported from 48 hospitals in 11 countries.

RESULTS

Gender, age, ventricular dimension, etiology, ethnology, myocardial mass, operative variation, presence or absence of mitral regurgitation, and transplant indication had no effects on event-free survival, which was defined as absence of death or ventricular failure that required a ventricular assist device or listing for transplantation. Preoperative patient conditions, such as duration of symptoms (> 9 vs < 3 years; p = 0.001), New York Heart Association (NYHA) class (Class IV vs < Class IV; p = 0.002), depressed contractility (fractional shortening [FS] < 5% vs > 12%; p = 0.001), and refractory decompensation that required emergency procedure (p < 0.001) were associated with reduced event-free survival. Five or more cases in each hospital led to significantly better outcomes than the initial four cases. Rescue procedures for 14 patients nonsignificantly improved patient survival (2-year survival 52%) over event-free survival (2-year survival 48%; p = 0.49), with improved NYHA class among survivors (3.6 to 1.8; p < 0.001). Outcome was better in 1999 than in all series before 1999 (p = 0.02) most likely due to patient selection, which was refined to avoid known risk factors such as reduced proportion of patients in NYHA Class IV, FS < 5%, and hospitals with experience in 10 or less cases. A combination of these risk factors could have stratified 17 high-risk patients with 0% 1-year survival and 26 low-risk patients with 75% 2-year event-free survival.

CONCLUSION

Avoidance of risk factors appears to improve survival and might help stratify high- or low-risk patients. Although less symptomatic patients with preserved contractility had better results after PLV, change of indication requires prospective randomized comparison with medical therapies or other approaches.

Partial left ventriculectomy: history, current status, and future role

Whereas discouraging clinical results and lack of scientific evidence decreased the initial interest in partial left ventriculectomy (PLV), factors contributing to success and failure have now been identified by clinical observations, theoretical analyses, and data from an international registry, which are herein reviewed to outline the current status and future role of this procedure as a treatment of heart failure.

Histopathology of resected myocardium and outcome of partial left ventriculectomy

BACKGROUND

Since preoperative hemodynamics are not proven to be a predictor of effects of partial left ventriculectomy (PLV), myocardial histopathology may be better correlated with effects and outcome of PLV.

METHODS

Myocyte size (micron) in the excised myocardium was measured in 338 patients undergoing PLV. Endocardial fibrosis, interstitial fibrosis, and inflammatory cell infiltration were enumerated as none = 0, mild = 1, moderate = 2, and severe = 3. These histopathologic observations were correlated with patients' postoperative survival.

RESULTS

Reduced survival was seen in patients with advanced (> or = moderate) interstitial fibrosis in all patients (n = 338, p = 0.064) and in the subgroup with nonischemic etiology (n = 229, p = 0.0039). Although correlation between endocardial and interstitial fibrosis was significant (r = 0.55, p < 0.01), endocardial fibrosis failed to correlate with postoperative survival. While Chagas' disease was associated with severe inflammation and poor survival, the presence of inflammatory cell infiltration had no effect on survival in all patients combined (p = 0.943). Although most patients (n = 266, 79%) had myocyte diameter over 30 micron, those with less hypertrophy (< 30 micron, n = 70, 21%) had a tendency toward increased survival (p = 0.067) regardless of underlying etiology.

CONCLUSION

Interstitial fibrosis may be an important factor in stratification of patients for repair (PLV) or replacement (transplantation). PLV may be more beneficial in patients with less hypertrophy, before develqpment of interstitial fibrosis. Endomyocardial biopsy might not predict the extent or variation in degree of interstitial fibrosis, which may be better evaluated by other metabolic or perfusion studies that measure overall myocardial histopathology and viability.

Current perspectives of partial left ventriculectomy in the treatment of dilated cardiomyopathy

OBJECTIVES

Partial left ventriculectomy has been performed as an alternative to heart transplantation in the treatment of severe cardiomyopathies. This investigation documents the clinical and left ventricular (LV) function effects of this procedure, associated, when necessary, with mitral insufficiency correction, in 43 patients with idiopathic dilated cardiomyopathy.

METHODS

Eighteen patients were in New York Heart Association class III and 25 in class IV. Seven of them were operated in cardiogenic shock. The procedure was associated with mitral annuloplasty in 32 patients and mitral replacement in three.

RESULTS

Nine patients (20.9%) died during the hospital period and the cause of death was associated with ventricular failure in seven patients. The other patients were followed up from 2 to 57 months (mean, 28.3 months). At 6 months of follow-up, eight patients were in functional class I, 13 in class II, three in class III and one patient was in class IV (P<0.001). On the other hand, nine patients died during the first 6 months and another six in the later postoperative period. The cause of late death was progressive heart failure in eight patients, and seven patients died because of arrhythmia related events. The actuarial survival was 58.1+/-7.5% at 1 year and 43.9+/-8.1% at 4 years of follow-up. Regarding ventricular function modifications, the LV diastolic volume decreased by around 25% and the LV ejection fraction increased from 17.8+/-4.7 to 22.3+/-7.9% (P<0.001), whereas significant changes in the cardiac index, stroke index and pulmonary pressures were also found 1 month after the operation. In the later follow-up, despite the maintenance of hemodynamic improvement, the LV diastolic volume tended to increase and returned to preoperative levels at 4 years, while a concomitant decrease in the LV ejection fraction was also observed.

CONCLUSION

Partial left ventriculectomy associated with mitral insufficiency correction improves LV function and ameliorates congestive heart failure in patients with idiopathic cardiomyopathy. Otherwise, the LV function benefits seem to be restricted by the possibility of progressive LV redilatation. Furthermore, the clinical application of this procedure is limited by the high mortality observed in the first postoperative months and by the possibility of heart failure progression and arrhythmia related events at late follow-up.

Surgical approaches to dilated cardiomyopathy

Heart failure is one of the leading causes of hospitalization in the United States today. Congestive heart failure is a chronic progressive disease with the common central element being the remodeling of the cardiac chamber associated with ventricular dilation. Secondary mitral regurgitation is a complication of end-stage cardiomyopathy and is associated with a poor prognosis. Historically, these patients were not considered operative candidates due to the high morbidity and mortality in this patient population. Heart transplantation is now considered the standard of treatment for select patients with end-stage heart disease, however, it is only applicable to a small number of patients. In an effort to address this problem, newer and alternative surgical approaches are evolving, including mitral valve annuloplasty, the Batista myoplasty, and cardiomyoplasty. When these operative techniques that alter the shape of the left ventricle are utilized, in combination with optimal medical management for heart failure, survival is improved and patients can avoid or postpone transplantation.