Factors affecting late survival after surgical remodeling of left ventricular aneurysms

Depleted Leukocyte Mitochondrial DNA Copy Number Correlates With Unfavorable Left Ventricular Volumetric and Spherical Shape Remodeling in Acute Myocardial Infarction After Primary Angioplasty

BACKGROUND

Left ventricular (LV) shape influences LV systolic function. It is possible to assess LV shape using 3-D echocardiography sphericity index (SI). Maintaining mitochondrial DNA copy number (MCN) is important for preserving mitochondrial function and LV systolic function after acute myocardial infarction (AMI). Information is limited, however, regarding the relationship between leukocyte MCN and the subsequent change in LV shape after AMI.Methods and Results:Fifty-five AMI patients undergoing primary angioplasty were recruited. Plasma MCN was measured before primary angioplasty using quantitative polymerase chain reaction. 3-D echocardiography measurement of SI was performed at baseline, and at 1-, 3-, and 6-month follow-up. AMI subjects with MCN lower than the median had a higher 6-month SI and LV volume compared with those with higher MCN. Baseline echocardiographic parameters were similar between the 2 groups. MCN was negatively correlated with 3- and 6-month SI, and 3- and 6-month LV volume. On multiple linear regression analysis, baseline plasma MCN could predict LV SI and LV volume at 6 months after primary angioplasty for AMI, even after adjusting for traditional prognostic factors.

CONCLUSIONS

In AMI patients, higher plasma leukocyte MCN at baseline was associated with favorable LV shape and remodeling at 6-month follow-up. Plasma leukocyte MCN may provide a novel prognostic biomarker for LV remodeling after AMI.

Left Ventricular Aneurysmectomy: Tailored Scar Excision and Linear Closure

Coronary artery bypass surgery with or without aneurysmectomy is used to treat patients with left ventricular aneurysm. There is debate about patient selection and the appropriate surgical technique. We analyzed the results of 102 consecutive patients who underwent left ventricular aneurysmectomy and reconstruction using a modified linear closure technique between 1992 and 2003. The mean age was 62 years, 81% of the patients were male, and 47% had an ejection fraction < 35%. The locations of the left ventricular aneurysms were anteroapical (75%), apical (21%), and posteroinferior (4%); 23% contained thrombi. Additional procedures included aortic valve replacement in 4, mitral valve repair in 1, and coronary bypass grafting in 98 patients; 3 underwent isolated repair of left ventricular aneurysm. Hospital mortality was 7% and long-term survival was 76% at a mean follow-up of 39 months. Most patients improved symptomatically postoperatively. Left ventricular aneurysm repair with tailored scar excision and a modified closure technique is associated with acceptable mortality and long-term survival.

Time series analysis of physiologic left ventricular reconstruction in ischemic cardiomyopathy

OBJECTIVE

The history of left ventricular reconstruction has demonstrated that the full spectrum of recoverable physiologic parameters is essential for a good functional result. We report the long-term outcome of a new surgical technique that arranges myocardial fibers in a near-normal disposition, also recovering left ventricular twisting.

METHODS

Between May 2006 and October 2013, 29 consecutive patients with previous anterior myocardial infarction and heart failure symptoms underwent physiologic left ventricular reconstruction surgery and coronary revascularization. Patients were examined by means of standard echocardiography and 2-dimensional speckle tracking at 8 time steps until 7 years after surgery. Ten geometric and functional parameters were evaluated at each step and analyzed by the linear mixed model test.

RESULTS

Hospital mortality was 0%. The mean percentage of indexed end-diastolic and end-systolic volume reduction was 45.7% and 50.9%, respectively. Ejection fraction and all of the volumes were significantly different in the postoperative period with a steady correction during time. Diastolic parameters were not worsened by surgical reconstruction. Ejection fraction and deceleration time showed a significant improvement during time. Left ventricular torsion increased immediately after the surgical correction from 2.8 ± 4.4 degrees to 8.7 ± 3.9 degrees (P = .02) and was still present 4 years after surgery.

CONCLUSIONS

Surgical conduction of ventricular reconstruction should be standardized to achieve the full spectrum of recoverable physiologic parameters. The renewal of ventricular torsion should be pursued as an adjunctive element of ventricular efficiency, mainly in ventricles that work at a critical level in the Frank-Starling relationship and pressure-volume loop.

Three-dimensional CFD/MRI modeling reveals that ventricular surgical restoration improves ventricular function by modifying intraventricular blood flow

Surgical ventricular restoration (SVR) is designed to normalize distorted ventricular shape and size in patients with left ventricular (LV) dysfunction and akinetic and dyskinetic segments. This study is aimed to quantify the characteristics of LV as a pump for a case before and after SVR, which is followed by coronary artery bypass grafting (CABG). We hypothesize that SVR+CABG improves heart flow. A patient with heart failure had magnetic resonance (MR) scans before and 4 months after SVR. LV endocardial geometries were semi-automated segmented and reconstructed using our customized algorithm. The arbitrary Lagrangian-Eulerian formulation of Navier-Stokes equations was solved to derive the flow patterns and calculate pressure differences in LV. After SVR, LV ejection fraction increased from 34% to 48% in patient but was still lower than normal (70%). Second, LV vortices were stronger than pre-surgery but still weaker than normal. The maximum pressure differences between ventricular base and apex increased from 180 to 400 Pa during diastole, from 252 to 560 Pa during systole, respectively. As anticipated, SVR reduced LV volumes and augmented LV ejection fraction. Three-dimensional CFD/MRI modeling suggests that improved diastolic and systolic ventricular function after SVR is associated with changes in intraventricular blood flow.

Melatonin protects against ischemic heart failure in rats

Ischemic injury, which occurs as a result of sympathetic hyperactivity, plays an important role in heart failure. Melatonin is thought to have antiatherogenic, antioxidant, and vasodilatory effects. In this study, we investigated whether melatonin protects against ischemic heart failure (HF). In Wistar albino rats, HF was induced by left anterior descending (LAD) coronary artery ligation and rats were treated with either vehicle or melatonin (10 mg/kg) for 4 weeks. At the end of this period, echocardiographic measurements were recorded and the rats were decapitated to obtain plasma and cardiac tissue samples. Lactate dehydrogenase, creatine kinase, aspartate aminotransferase, alanine aminotransferase, and lysosomal enzymes (β-D-glucuronidase, β-galactosidase, β-D-N-acetyl-glucosaminidase, acid phosphatase, and cathepsin-D) were studied in plasma samples, while malondialdehyde and glutathione levels and Na+, K+-ATPase, caspase-3 and myeloperoxidase activities were determined in the cardiac samples. Sarco/endoplasmic reticulum calcium ATPase (SERCA) and caveolin-3 levels in cardiac tissues were evaluated using Western blot analyses. Furthermore, caveolin-3 levels were also determined by histological analyses. In the vehicle-treated HF group, cardiotoxicity resulted in decreased cardiac Na+, K+-ATPase and SERCA activities, GSH contents and caveolin-3 levels, while plasma LDH, CK, and lysosomal enzyme activities and cardiac MDA and Myeloperoxidase (MPO) activities were found to be increased. On the other hand, melatonin treatment reversed all the functional and biochemical changes. The present results demonstrate that Mel ameliorates ischemic heart failure in rats. These observations highlight that melatonin is a promising supplement for improving defense mechanisms in the heart against oxidative stress caused by heart failure.

Second successful surgical ventricular reconstruction: a cardiac magnetic resonance imaging illustration

This case reports a magnetic resonance imaging (MRI) illustration of a successful ventricular reconstruction of a left ventricle pseudoaneurysm that developed four months after postmyocardial infarction ventricular repair. Thus, preoperative non-invasive MRI techniques are valuable diagnostic tools in this setting. Indeed, the present case shows that MRI greatly helped in the management and surgical decision-making.

Left ventricular aneurysm repair: a comparison of linear versus patch remodeling

BACKGROUND

Surgical repair of left ventricular (LV) aneurysm has been performed for around 50 years. However, the most appropriate surgical approach remains undetermined. This study was undertaken to compare the efficacy of 2 established techniques, linear versus patch remodeling, for repair of dyskinetic LV aneurysms.

METHODS

We retrospectively reviewed the records of 49 patients (mean age, 69.8 +/- 7.3 years) who had operation for postinfarction dyskinetic LV aneurysm between 1996 and 2006. Thirty-one patients underwent patch remodeling and 18 underwent linear repair. Short-term and mid-term outcomes, including complications, cardiac function and mortality, were assessed.

RESULTS

Overall inhospital surgical mortality, major complications and early hemodynamics showed no significant differences between the 2 groups. During a mean follow-up of 44.0 +/- 34.4 months, 8 patients died, with 4 due to cardiac-related causes. Actuarial survival rates at 1, 5 and 10 years were 85.7%, 69.9% and 45.7%, respectively. Functional class improved from 2.51 +/- 0.59 to 1.66 +/- 0.54 among the mid-term survivors (p < 0.001), with no significant difference between the 2 groups. Multivariate analysis identified preoperative NYHA functional class >or= 3 as an independent risk factor for overall mortality (p = 0.008). Mid-term follow-up revealed that LV ejection fraction improved from 26.5 +/- 7.2% to 34.1 +/- 7.9% (p < 0.001) in the patch group, and from 26.3 +/- 9.0% to 32.0 +/- 9.2% in the linear group (p = 0.032). In contrast, right ventricular ejection fraction improved from 49.4 +/- 10.1% to 52.0 +/- 7.3% (p = 0.190) in the patch group, but deteriorated from 55.0 +/- 6.3% to 50.3 +/- 8.6% in the linear group (p = 0.029).

CONCLUSION

These findings indicate that the 2 repair techniques have similar effectiveness with respect to short- and mid-term outcomes except for right ventricular ejection fraction. We suggest that the selection of repair technique for LV aneurysms should be individualized for each patient based on aneurysm size and extent of the scarring process into the septum and subvalvular mitral apparatus.

A new surgical ventricular restoration technique to reset residual myocardium's fiber orientation: the "KISS" procedure

BACKGROUND

The history of surgical reconstruction of the left ventricle after an anterior myocardial infarction shows an evolution of techniques which tend to a more and more physiologic restoration of ventricular shape and volume, with increasing attention to the orientation of myocardial fibers.

METHODS

We set a new surgical procedure for endoventricular patch reconstruction technique with the aim to rebuild a physiologic shape and volume of the left ventricle caring about realignment of myocardial fibers orientation. Peculiarities of this reconstruction are the shape of the patch (reduction of minor axis compared with currently used oval-shaped patch) and the asymmetrical way of suturing it inside the ventricle.

RESULTS

We present a detailed description of operative steps of this procedure, and we add some relevant surgical hints to clarify its peculiarities. Most of the patients operated on with this technique showed the original renewal of apical rotation and left ventricular torsion as specific index of the restoration of physiologic fiber orientation: we report an exemplary case of at-sight recovery of apical rotation in the operating room.

CONCLUSION

This technique can represent a reproducible new way to realign myocardial fibers in a near-normal setting, improving the physiological restoration of ischemically injured left ventricle. It could be also the basis to reconsider surgical treatment for heart failure.

Diagnosing left ventricular aneurysm from pseudo-aneurysm: a case report and a review in literature

Rupture of the free wall of the left ventricle (LV) is a catastrophic complication occurring in 4% of patients after myocardial infarction (MI) and in 23% of those who die of MI. Rarely the rupture is contained by an adherent pericardium creating a pseudo-aneurysm. This clinical finding calls for emergency surgery. If no ruptures are detectable and myocardium wall integrity is confirmed, we are in the presence of a true aneurysm, which can be treated by means of elective surgery. Differentiation between these two pathologies remains difficult. We report the case of a patient with a true aneurysm, initially diagnosed as pseudo-aneurysm at our institution; we have reviewed the literature on this difficult diagnosis and outlined characteristic findings of each clinical entity.

Patch size, shape and orientation affect geometrical outcomes of surgical anterior ventricular restoration

OBJECTIVES

To verify whether the use of a small, oval-shaped patch limits the trend toward re-dilatation compared to endoventricular circular patch plasty and leads to different geometrical and functional results in surgical anterior restoration.

METHODS

Thirty-seven patients with ischemic cardiomyopathy after anterior myocardial infarction end-systolic volume index of > or =45 ml/m2, ejection fraction of < or =35%, and no combined mitral procedures, underwent surgical anterior ventricular restoration between January 2000 and April 2003: 18 patients (group 1) were operated on using the endoventricular circular patch plasty technique (mean patch area 9.6 cm2) and 19 patients (group 2) received a small, obliquely oriented, oval-shaped patch (mean patch area 6.2 cm2). Ten geometrical parameters were studied preoperatively and at least 6 and 12 months after surgery. Data were analyzed using repeated-measures ANOVA, chi2, paired and unpaired Student's t-test, and binary logistic regression.

RESULTS

Group 1 showed a worsening over time in systolic and diastolic longitudinal length, end-diastolic volume (P < 0.001), end-diastolic volume index (P = 0.006), end-systolic volume (P = 0.005), and end-systolic volume index (P = 0.03). Group 2 showed an improvement in percentage of akinesia and wall motion score index (P < 0.001) and a worsening only in end-systolic diameter (P = 0.03) and end-diastolic volume (P = 0.04). At 12-month follow-up, ANOVA revealed that the oval patch positively influenced end-diastolic volume (P = 0.03), end-systolic volume (P = 0.03), and end-systolic volume index (P = 0.05), and group 2 had a significantly higher number of patients with an end-systolic volume index of <45 ml/m2 (P = 0.01).

CONCLUSION

The use of a small, narrow, obliquely oriented, oval patch may help to prevent adverse ventricular remodeling over time.

Left Ventricular Reconstruction by Modified Linear Technique with Absorbable Suture

BACKGROUND

Linear and endoventricular techniques of left ventricular (LV) reconstruction often utilise prosthetic material for epicardial reinforcement or endocardial patch. We report a technique of LV aneurysm repair using absorbable suture without prosthetic material.

METHODS

Between November 1999 and August 2004, 55 patients underwent linear LV reconstruction, for ischaemic cardiomyopathy, using only continuous 3/0 polydioxanone suture. Survival, functional class and echocardiographic outcomes are reported.

RESULTS

Fifty-two patients (mean age 64+/-10 years) were studied. There was no perioperative mortality and the Kaplan-Meier survival at five years was 81%. Fifty-one patients underwent postoperative follow up (mean 28 months) with echocardiography (mean 20 months). There were no recurrent aneurysms. The postoperative LV eccentricity index (EI) was 0.72 (CI 0.48-0.9). Mean LV ejection fraction increased from 0.33+/-0.09 preoperatively to 0.41+/-0.15 at late follow up (mean within patient change 0.08+/-0.15, p=0.003). Mean symptom class improved from 3.3+/-0.8 to 1.6+/-0.7 (mean within patient improvement 1.6+/-1.0, p<0.001). Mitral regurgitation of grade 2/4 was identified in six patients and grade 3/4 in one patient.

CONCLUSION

Linear repair with absorbable suture material and without prosthetic material may be safely undertaken with good early and mid-term results.

Rewind the heart: a novel technique to reset heart fibers' orientation in surgery for ischemic cardiomyopathy

Ischemic cardiomyopathy is the most common cause of dilated cardiomyopathy and congestive heart failure. It affects approximately 1 out of 100 people, most often middle-aged to elderly men. Left ventricular restoration surgery is a challenging therapeutic approach to this pathology: it aims to rebuild a near-normal ventricular chamber in a heart damaged by a myocardial infarction, reducing its volume and improving the fraction of blood ejected by each systole. This is obtained by eliminating the akinetic/dyskinetic part of the cardiac muscle and closing the final defect with or without a synthetic patch. Optimization of surgical repair is mandatory as far as ischemic cardiomyopathy is a worldwide disease responsible for many cardiac deaths and because of its potential use as an alternative to heart transplantation in selected patients. Until now, this surgery has been performed without caring for myocardial fibers' disposition but recent evidences clarified the key role of fibers' alignment in heart physiology. The myocardium of the left ventricle has a unique three-dimensional, multilayered structure: it constitutes the anatomical basis for the cardiac function and for left ventricular torsion, a key movement of normal heart. Myocardial infarction alters myocardial structure in the site of the necrosis and subsequent cardiomyopathy eliminates left ventricular torsion. On the other hand, histological evidences show that myofibers' orientation in the thickness of residual normal myocardium is not changed and that transmural courses of fiber orientation angles near infarct zones were similar to those of normal myocardium. We hypothesize that, with a particular surgical technique, it could be possible to realign the anatomically normal fibers of the residual myocardium in order to rebuild a physiologic setting. We planned a novel surgical technique of left ventricular restoration using a very narrow, string-shaped patch and a particular suturing sequence and technique, whose aim is to near normally oriented residual myocardial fibers. The renewal of left ventricular torsion was evident at sight just at the end of this kind of ventricular restoration, still in the operating room, then confirmed by 2D speckle tracking echocardiography. These observations are indirect proofs of fibers' realignment, as the torsion movement of the left ventricle is due to the interlaced, oblique orientation of myocardial fibers. We herein propose a theoretical explanation of this outcome, drawing a geometrical modeling of the surgical procedure.

Surgery of left ventricular aneurysm: a meta-analysis of early outcomes following different reconstruction techniques

BACKGROUND

The purpose of this study is to assess the effects of linear and geometric left ventricular aneurysm reconstruction on early postoperative outcomes.

METHODS

A search of computerized databases supplemented with manual bibliographic review was performed for all peer-reviewed English language publications concerning randomized and nonrandomized studies reporting the results of left ventricular reconstruction after both linear and geometric reconstruction techniques. Meta-analyses of several short-term outcomes were performed.

RESULTS

No randomized trial was identified. Eighteen nonrandomized trials were found with a total of 1,814 and 803 patients who underwent linear and geometric reconstruction, respectively. Meta-analysis of all studies (n = 18) revealed an increased risk of in-hospital death for patients undergoing linear reconstruction (relative risk = 1.59, 95% confidence interval: 1.12 to 2.26, p = 0.01). The subanalysis of studies in which linear reconstruction was adopted mainly in the first period of time, and geometric reconstruction was adopted in a later phase, still showed a significant advantage in terms of in-hospital mortality for patients undergoing geometric reconstruction (n = 11 studies, relative risk = 1.89, 95% confidence interval: 1.22 to 2.93, p = 0.004). By contrast, when the two surgical approaches were carried out in the same time lag, there was no difference between linear and geometric reconstruction techniques (n = 7 studies, relative risk = 1.04, 95% confidence interval: 0.57 to 1.92, p = 0.89). No differences in the other outcomes of interest were observed.

CONCLUSIONS

The advantage for geometric reconstruction techniques in terms of in-hospital mortality shown in some studies can be an effect of learning curve or of improvement over time in management of these difficult patients. Further studies are required to clarify this issue.

A new shape for an old function: lasting effect of a physiologic surgical restoration of the left ventricle

BACKGROUND

Long-term morphofunctional outcome may vary widely in surgical anterior left ventricular wall restoration, suggesting variability in post-surgical remodeling similar to that observed following acute myocardial infarction. The aim of this pilot study was to demonstrate that surgical restoration obtained with a particular shape of endoventricular patch leads to steady morphofunctional ventricular improvement when geometry, volume and residual akinesia can be restored as normal as possible.

METHODS

This study involved 12 consecutive patients with previous anterior myocardial infarction, dilated cardiomyopathy and no mitral procedures, who underwent left ventricular reconstruction and coronary revascularization between May 2002 and May 2003 using a small, narrow, oval patch aiming at a volume <or= 45 mL/m2 with elliptical shape. Eleven geometric parameters were examined preoperatively and at least 3, 12 and 24 months after the operation by serial echocardiographic studies and evaluated by paired t test taking the time of surgery as a starting point for remodeling.

RESULTS

All patients were in NYHA class 1 at follow-up. Patch geometry obtained a conical shape of the ventricle with new apex, physiologic rearrangement of functioning myocardial wall and small residual akinesia. Ventricular changes at the four time-points showed that all parameters improved significantly compared to preoperative values (end-diastolic volume = 184.2 +/- 23.9 vs 139.9 +/- 22.0, p = 0.001; vs 151.0 +/- 33.8, p = 0.06; vs 144.9 +/- 34.0, p = 0.38; end-systolic volume = 125.7 +/- 20.6 vs 75.2 +/- 14.1, p = 0.001; vs 82.1 +/- 23.9, p = 0,18; vs 77.1 +/- 19.4, p = 0.41) without further changes during follow-up except for wall motion score index (2.0 +/- 0.2 to 1.7 +/- 0.2, to 1.4 +/- 0.2, to 1.3 +/- 0.2) and percentage of akinesia (30.4 +/- 7.5 to 29.3 +/- 4.2, to 19.8 +/- 11.6, to 14.5 +/- 7.2) which slowly and significantly improved suggesting a positive post-surgery remodeling.

CONCLUSION

Ventricular reconstruction caring of physiological shape, volume, revascularization and residual akinesia obtained a steady geometry. Positive remodeling and equalization of geometrical outcome may persistently prevent long-term redilation.