Postoperative Left Ventricular Remodeling Research Articles

A new device to treat mitral valve regurgitation: a proof of concept in bench test study

Mitral valve repair is typically performed by implanting a ring-like device at the valve annulus to reshape the annulus and to improve leaflet coaptation. In most cases, some additional procedures are needed, including leaflet resection and artificial chordae implantation. However, artificial chordae implantation could be technically challenging and postoperative left ventricular remodeling could increase the risk of recurrent mitral regurgitation. We propose an innovative annular device made of chromo-cobalt, finalized not only to reshape the annulus but also to enable anchoring of leaflets to a fixed intraventricular structure. Durability evaluation of the device was tested by applying eight radial force vectors equally spaced along the ring and related fatigue analysis. To evaluate the efficacy of the mitral valvuloplasty using the tested ring, the device was implanted in five adult swine hearts. Functional analysis of the ring was performed by measuring left ventricular pressure and fluid volume loss, following implantation in normal and dysfunctional mitral valve leaflets. Both fatigue and functional analysis showed satisfactory and promising results in terms of durability and efficacy of mitral valve repair. Because of its favorable durability and functional characteristics this device appears promising and provides good results in terms of valve competence, thus avoiding both manipulations of papillary muscles and interference in left ventricular hemodynamics. However, an in vivo test is mandatory to fully understand the impact of the device on subvalvular apparatus.

Left ventricular reverse remodeling and function by strain analysis in aortic stenosis: A CMR analysis of the EPICHEART study

Introduction and objectivesIn severe aortic stenosis (AS), the impact of aortic valve replacement (AVR) on left ventricular (LV) systolic function assessed by strain and measured by echocardiography or cardiac magnetic resonance (CMR) has been controversial. We aimed to investigate LV systolic myocardial function changes six months after AVR using global longitudinal (GLS), circumferential (GCS) and radial (GRS) strain derived from CMR imaging. MethodsWe included 39 severe AS patients (69.3±7.8 years; 61.5% male) with preserved LV ejection fraction (LVEF) who were recruited as part of the EPICHEART study and underwent successful AVR (aortic valvular area: 0.8 cm2 (IQR: 0.2) pre- to 1.8 cm2 (IQR:0.5) post-AVR). Structural and functional parameters were assessed at baseline and six months after AVR, including LV GRS, GCS and GLS analysis by CMR, using cine short-axial and two-, three-, and four-chamber long-axial view. Comparison between baseline and postoperative LV remodeling was performed using Student t-test and Wilcoxon test. ResultsAt six-month follow-up, LV mass, end-diastolic and end-systolic volumes, stroke volume, cardiac output, lateral E/e’, tricuspid annular plane systolic excursion, right ventricular (RV) S wave velocity, GLS [-15.6% (IQR: 4.39) to -13.7% (IQR: 4.62)] and GCS [-17.8±3.58% to -16.1±2.94%] reduced significantly, while LVEF and GRS remained unchanged and lateral e’ velocity increased. ConclusionsDespite favorable reverse LV structural and diastolic functional remodeling six months following AVR, GLS and GCS assessed by CMR reduced compared to baseline, LVEF remained unchanged. The clinical utility and timing of assessment of postoperative strain changes as a marker of systolic function progression needs further research.

Risk factors of persistent ventricular arrhythmias after mitral valve repair in Barlow disease patients: six-year follow-up

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Improvement in malignant ventricular arrhythmias (VA) has been reported after mitral valve surgery in some mitral valve prolapse patients (MVP) with severe degenerative mitral regurgitation. Mitral annular disjunction, posterior systolic curling, and mitral annular abnormal contractility are associated with arrhythmic MVP and underwent correction during the mitral valve repair. However, mitral valve disease progression and ventricular arrhythmic substrates (left ventricular fibrosis of papillary muscles and basal posterior wall) could be potential substrates for persistent malignant arrhythmias even after surgical correction. Our aim was to evaluate the risk factors of persistent VA after mitral valve repair in Barlow’s disease patients in six-year follow-up. Methods 30 consecutive patients (mean age 53.1 ± 9.4, 47% male) who underwent mitral valve repair for severe mitral regurgitation (MR) due to mitral valve prolapse were enrolled in our observational, prospective, single-center study. Resected abnormal segments of the mitral leaflets were examined by experienced pathologists for signs of myxomatous degeneration. Transthoracic echocardiography and 24-hour Holter monitoring were performed pre- and postoperatively annually. PVCs and nonsustained ventricular tachycardia (VT) runs were reviewed. Results All patients survived the operation. There was only one sudden cardiac death on sixth year of follow-up. During 173 person-years of follow-up 3 patients (10%) had developed recurrent moderate to severe (≥2) MR. The total number of PVCs and non-sustained ventricular tachycardia runs dropped significantly in 1st (p=.04, Wilcoxon matched pairs test) and 2nd (p=.03), years of postoperative follow-up. Postoperative incidence of PVCs and VT correlated strongly with postoperative end-diastolic LV diameter (EDD rs=.69; p=.005), moderate negatively with LV ejection fraction (EF rs=-.55; p=.001). Advanced myxomatous degeneration assessed by pathologists and MV posterior leaflet’s thickness ≥5 mm after repair assessed by echocardiographer associated with postoperative PVCs and VT (rτ=.58; p=.045 and rs=.62; p=.002, respectively). Recurrent MR also strongly associated with postoperative PVCs and VT (rs=.76; p=.0018). In univariate analysis, advanced myxomatous degeneration (p=.008), postoperative end-diastolic LV diameter (p=.001), and low EF (p=.003) were identified as risk factors of persistent PVCs/VT after surgery. Conclusions Advanced myxomatous degeneration assessed by pathologists or echocardiographer and postoperative left ventricular remodeling are associated with persistent malignant ventricular arrhythmias. Further investigation in larger cohorts to evaluate the association between degenerative mitral valve disease and ventricular arrhythmias is needed.

Long-term surgical results of anomalous origin of the left coronary artery from the pulmonary artery repair in infants and older patients.

The objective of this study was to compare the long-term surgical results of anomalous origin of the left coronary artery (LCA) from the pulmonary artery repair between infants and older patients. This is a retrospective study of patients undergoing anomalous origin of the LCA from the pulmonary artery repair between 1982 and 2018. Thirty-five patients were enrolled and divided into two groups based on their age: infants (<1 year of age: n = 11) and older patients (>1 year of age: n = 24). Median age was 5.2 months in infants and 6.3 years in older patients. The procedure included 24 LCA implantations and 11 intrapulmonary baffle repairs. Early mortality was recorded only in two infants (18%). Early complications included two low output syndrome (18%). Survival and freedom from reoperation at median follow-up of 17.2 years were not significantly different between groups (survival, 81.8 ± 11.6% vs. 94.1 ± 5.7% [p = .3846]; freedom from reoperation, 77.8 ± 13.9% vs. 90.0 ± 6.8% [p = .1175]). Mitral regurgitation (MR) developed substantially in two older patients in the long-term. In infants, significant improvements of fractional shortening (p = .0252) and left ventricular (LV) end-systolic (p = .0142) and end-diastolic diameter (p = .0157) occurred at 1 month. Although there was no significant difference in survival and reoperation rate, the postoperative LV remodeling occurred more evident and rapid in infants. Worsening of MR in the long-term was observed only in older patients.

Effects of percutaneous coronary intervention on cardiac function in ischemic cardiomyopathy patients with different left ventricular ejection fraction and SYNTAX score≤22

Objective: To evaluate the clinical impact of percutaneous coronary intervention (PCI) on left ventricular myocardial remodeling and main adverse cardiovascular and cerebrovascular events (MACE) in ischemic cardiomyopathy patients with different left ventricular ejection fraction and SYNTAX score≤22. Methods: A total of 191 ischemic cardiomyopathy patients who underwent PCI in Department of Cardiology from May 2017 to October 2018 were enrolled in this study, and they were divided into three groups according to preoperative left ventricular ejection fraction (≥50% group, 36%~49% group and ≤35% group). The main outcomes and left ventricular ejection fraction, left ventricular end-diastolic volume were analyzed at 12 months follow-up. The main outcomes were the recurrence of acute left ventricular failure, recurrent angina, restenosis, revascularization, non-fatal myocardial infarction, cardiovascular death and non-cardiovascular death. Results: The incidence of MACE was 32.6% (15 cases) in ≥50% group, 32.0% (31 cases) in 36%-49% group, 45.8% (22 cases) in ≤35% group, respectively, which was lower in the first two groups than in ≤35% group, but there was no statistically significant difference among the 3 groups (P=0.231). The incidence of acute left ventricular failure in the three groups was 2.2%, 12.4% and 22.9%, respectively, and there was statistically significant difference among the 3 groups (P= 0.01). Multivariate analysis indicated that preoperative left ventricular ejection fraction ≤35% was an independent predictor of acute left ventricular failure (OR=2.696, 95%CI: 1.099-6.612, P=0.030). Compared with baseline data, left ventricular end-diastolic volume ((62±4) mm vs (56±5) mm, P<0.001), left atrium ((42±6) mm vs (40±6) mm, P<0.001) decreased significantly 1 year after PCI. However, left ventricular ejection fraction ((43±10)% vs (51±13)%, P<0.001) increased significantly. At 1 year, left ventricular remodeling related parameters were detected in 3 groups, and there was statistically significant difference in left ventricular end-diastolic volume ((53.1±0.6) mm vs (55.1±0.5) mm vs (59.1±0.7) mm, P<0.001), left ventricular ejection fraction ((62.1±1.1)% vs (51.4±1.0)% vs (37.0±1.5)%, P<0.001) among the 3 groups. Conclusions: Coronary vascular reopening with PCI in patients with ischaemic cardiomyopathy and SYNTAX score≤22, can improve prognosis of patients with preoperative left ventricular ejection fraction>35% significantly, but not in those with preoperative left ventricular ejection fraction≤35%. Preoperative left ventricular ejection fraction may be an independent predictor of acute left ventricular failure in patients with ischemic cardiomyopathy and SYNTAX score≤22, postoperative left ventricular remodeling and left ventricular systolic function correlate with preoperative left ventricular ejection fraction.

High plasma levels of exosomal miR21 and miR133a are associated with LV reverse remodelling after surgical mitral valve repair

Mitral valve regurgitation (MR) is the most common cardiac valvular disease associated with increased morbidity and mortality. Patients are characterized by volume overload and progressive increase of left ventricular (LV) end‐diastolic volume (EDV). Surgery is recommended for patients with substantial loss of global cardiac function (LV ejection fraction, LVEF). A correctly timed surgery for MR can reverse LV remodeling. Identification of patients at high risk of post‐operative LV remodeling may help to act with preventive strategies. In this scenario, microRNAs delivered by plasma exosomes (pEXOs), smallest extracellular nanovesicles, might have a predictive value. Primary MR patients (N=19; 45–71 y.o.) underwent implantation of a prosthetic mitral ring. LV remodeling was assessed by cadiac magnetic resonance imaging and pEXOs were isolated by optimized ultracentrifugation before surgery (T0) and six months after surgery (T1). Isolated pEXOs were quantified by nanoparticle tracking analysis (NanoSight) and miR‐1, miR‐21, miR‐133a and miR‐208a were measured by RT‐qPCR. The same analysis was performed healthy subjects with normal cardiac function (Control, N=8). pEXOs levels at T0 were lower (−32%, p=0.02) in patients with worst postoperative LV function, while they were higher at T1 (+31%, p=0.03) in patients with LV reverse remodeling after surgery. At T1, the increase in pEXOs levels was associated to decreased heart mass index (−13%, p=0.02) and higher levels of exosomal miR‐21 (+78%, p=0.02) and miR‐133a (+69%, p=0.05) were detected in patients with improved LV function. In conclusion, higher postoperative levels of pEXOs and exosomal miR‐21 and 133a mark LV reverse remodeling after mitral valve repair. Combined measurements of circulating exosomes and their microRNAs cargo might represent potential novel perioperative markers in patients with MR.

Assessment of Left Ventricular Reverse Remodeling by Cardiac MRI in Patients Undergoing Repair Surgery for Severe Aortic or Mitral Regurgitation

To evaluate left ventricular (LV) reverse remodeling after repair surgery for mitral regurgitation (MR) or aortic regurgitation (AR), aiming at determining optimal preoperative thresholds for normalization of LV volumes and function after surgery. Observational prospective cohort study. Single-center, academic, tertiary care cardiovascular center. Patients and volunteers. Cardiac magnetic resonance with measurement of indexed LV end-diastolic volume (LVEDVi) and end-systolic volume (LVESVi), mass (LVmassi), and ejection fraction (LVEF) was performed preoperatively and postoperatively. The authors included 29 patients with AR and 59 patients with MR (46 ± 12 and 56 ± 12 years, follow-up 222 ± 57 days). Both AR and MR repair resulted in a significant reduction of LV volumes and mass (respectively, delta change in LVEDVi -55 mL/m² and -43 mL/m²; in LVESVi -26 mL/m² and -10 mL/m²; and in LVmassi -24 g/m² and -12 g/m²; p < 0.001 for all). Yet despite the absence of perioperative necrosis, 7 (24%) patients with AR had persistent LV dilatation (LVEDVi >106 mL/m²) relative to controls and 16 (27%) patients with MR developed systolic LV dysfunction (LVEF <50%) postoperatively. Binary logistic regression analysis indicated preoperative LV volumes as the most accurate parameter for predicting both incomplete LV reverse remodeling in AR and LV dysfunction in MR. Receiver operating characteristic-determined thresholds were LVEDVi >155 mL/m² for AR and >129 mL/m² for MR. Although both AR and MR repair allow significant reverse postoperative LV remodeling, persistent LV dilatation after AR correction and systolic LV dysfunction after MR repair are common and best predicted by increased preoperative LV volumes. This highlights the importance of considering LV volumes in the decision-making process.

Technique to avoid left ventricular outflow tract obstruction

Preserving the subvalvular mitral valve apparatus during mitral valve replacement is extremely important to minimize progressive postoperative left ventricular remodeling and dysfunction. We describe a simple and reproducible surgical technique that prevents the complications that can occur after total mitral anterior leaflet preservation.

Predicting Left Ventricular Dysfunction after Surgery in Patients with Chronic Mitral Regurgitation: Assessment of Myocardial Deformation by 2-Dimensional Multilayer Speckle Tracking Echocardiography.

Background and ObjectivesThe development of postoperative left ventricular (LV) dysfunction is a frequent complication in patients with chronic severe mitral valve regurgitation (MR) and portends a poor prognosis. Assessment of myocardial deformation enables myocardial contractility to be accurately estimated. The aim of the present study was to evaluate the predictive value of preoperative regional LV contractile function assessment using two-dimensional multilayer speckle-tracking echocardiography (2D MSTE) analysis in patients with chronic severe MR with preserved LV systolic function.Subjects and MethodsForty-three consecutive patients with chronic severe MR with preserved LV systolic function scheduled for mitral valve replacement (MVR) or MV repair were prospectively enrolled. Serial echocardiographic studies were performed before surgery, at 7 days follow-up, and at least 3 months follow-up postoperatively. The conventional echocardiographic parameters were analyzed. Global longitudinal strain (GLS) was obtained quantitatively by 2D MSTE.ResultsThe mean age of patients was 51.7±14.3 years and 25 (58.1%) were male. In receiver-operating characteristic curve analysis, the most useful cutoff value for discriminating postoperative LV remodeling in severe MR with normal LV systolic function was -20.5% of 2D mid-layer GLS. Patients were divided into two groups by the baseline GLS -20.5%. Preoperative GLS values strongly predicted postoperative LV remodeling or LV dysfunction. The postoperative degree of decrease in LV end-diastolic dimension might be an additive predictive factor.ConclusionSTE can be used to predict a decrease in LV function after MVR in patients with chronic severe MR. This promising method could be of use in the clinic when trying to decide upon the optimum time to schedule surgery for such patients.

Mass attached to mechanical mitral valve mimicking a thrombus

Mitral valve replacement with preservation of chordae tendineae and papillary muscles is a well-known technique which has proved beneficial by reducing postoperative left ventricular remodeling and preserving left ventricular function. This advantage has been demonstrated in functional mitral valve regurgitation as well as mitral valve regurgitation due to rheumatic disease. Regarding complications of this technique, several of them have been reported, papillary muscle rupture being one of them. We describe a clinical case of this weird but possible kind of complication.

Surgical treatment of post-infarction left ventricular aneurysm: clinical analysis

To explore the clinical experiences, efficacies and postoperative left ventricular remodeling changes of surgical ventricular reconstruction in the treatment of post-infarction left ventricular aneurysm. The investigators reviewed retrospectively the clinical data, operative approaches and follow-up outcomes of consecutive 194 patients with post-infarction left ventricular aneurysm, who underwent surgical ventricular reconstruction between January 1997 and December 2009. There were 54 cases in the linear group and 137 cases in the endoventricular patch plasty group. The changes of ventricular remodeling were measured by peri-operative and follow-up echocardiography. All patients underwent surgery with a mean cardiopulmonary bypass duration of (103 ± 35) min and aortic cross clamp duration of (62 ± 26) min. There were 8 per-operative deaths with a mortality rate of 2.2%. Angina pectoris of other cases disappeared and heart function greatly improved. After operation, the ventricular remodeling results showed that in the linear group, there was not significant difference in the changes of ventricular remodeling of post-op 2 weeks, 6 months, 1 year and 5 years versus pre-operation. However, in the endoventricular patch group, the changes of ventricular remodeling of post-op 2 weeks and follow-up 6 months versus pre-operation were significantly reduced (P < 0.05). End-systolic volume (LVESV) reduced from (129 ± 27) ml to (65 ± 8) ml and end-systolic volume index (LVESVI) decreased from (104 ± 14) ml/m(2) to (44 ± 6) ml/m(2) and the subgroup of LVEF < 35% was the most significant in the changes of LVESV and LVESVI. But LVEF improved significantly at post-operation and follow-up (from preoperation 42% ± 11% to 52% ± 7% during follow-up). For patients with infarction left ventricular aneurysm, left ventricular reconstruction is quite effective. The choice of operative approaches is determined by the size and range of ventricular aneurysm. Both string suture and endoventricular patch plasty technique can yield similarly satisfactory surgical outcomes. After operation, ventricular volume significantly decreases and cardiac function greatly improves.

Efficacy of Low-Dose Continuous Infusion of .ALPHA.-Human Atrial Natriuretic Peptide (hANP) During Cardiac Surgery Possibility of Postoperative Left Ventricular Remodeling Effect

The aim of the present study was to evaluate the efficacy of alpha-human atrial natriuretic peptide (hANP) in cardiac surgery under cardiopulmonary bypass (CPB). A prospective randomized study was conducted with 150 patients who underwent scheduled coronary artery bypass grafting to compare a group of patients receiving 0.02 microg x kg(-1) x min(-1) of hANP from the initiation of CPB with a group not receiving hANP. Hemodynamics, levels of atrial and brain natriuretic peptides (BNP), angiotensin-II and aldosterone, renin activity, and left ventricular (LV) function were examined. The hANP group showed significantly lower renin activity and lower levels of angiotensin-II and aldosterone during the early postoperative period, compared with the non-hANP group. The incidence of postoperative ventricular arrhythmia and the postoperative peak level of creatine kinase-MB were significantly lower in the hANP group. BNP at 1 month after surgery and measures of LV function were also significantly lower in the hANP group. Low-dose continuous infusion of hANP during cardiac surgery not only had a compensatory effect for the imperfections of CPB during the early postoperative period but also an inhibitory effect on postoperative LV remodeling and a reduction in ischemia/reperfusion injury. hANP should be part of the postoperative care for cardiac surgery.

Early postoperative changes in left ventricular chamber size, architecture, and function in aortic stenosis and aortic regurgitation and their relation to intraoperative changes in afterload: a prospective two-dimensional echocardiographic study.

We prospectively studied 16 patients with isolated aortic stenosis and eight with isolated aortic regurgitation undergoing aortic valve replacement, using two-dimensional echocardiography preoperatively, intraoperatively, and 41 +/- 7 days postoperatively to calculate the intraoperative change in afterload, quantify the postoperative changes in left ventricular chamber size, architecture, load and function, determine whether the postoperative left ventricular remodeling correlated with the intraoperative change in afterload in aortic stenosis and aortic regurgitation, and assess whether preoperative afterload excess precluded postoperative improvement in left ventricular function. Preoperative left ventricular mass, end-systolic meridional and circumferential wall stresses, ejection fraction, and stress-shortening relations in patients with aortic stenosis and aortic regurgitation were similar. However, our patients with aortic regurgitation had severe systolic dysfunction, with ejection fraction less than 55% in all but one patient, compared with only 10 of 16 patients with aortic stenosis. Left ventricular end-diastolic volume, mass/volume ratio, and chamber shape were significantly different in patients with aortic stenosis and aortic regurgitation (174 +/- 64 vs 294 +/- 140 ml, p less than .01; 1.81 +/- 0.63 vs 1.14 +/- 0.18, p less than .01; and 0.59 +/- 0.09 vs 0.69 +/- 0.09, p less than .05, respectively). Intraoperative end-systolic meridional and circumferential stresses fell significantly in patients with aortic stenosis but remained unchanged in those with aortic regurgitation. The changes in left ventricular volume and ejection fraction during early postoperative remodeling (6 weeks) correlated with the intraoperative change in afterload in patients with aortic stenosis. In contrast, there was no intraoperative change in afterload in patients with aortic regurgitation and no significant changes in left ventricular volume, architecture, or function at 6 weeks or at 6 months. The differences in left ventricular remodeling and changes in function between patients with aortic stenosis and aortic regurgitation in the early postoperative period most probably relates to the major difference in intraoperative reduction in afterload, although a contributory role may have been played by the preoperative left ventricular dysfunction in those with aortic regurgitation that was underestimated by measurement of ejection fraction.