Preoperative Left Ventricular End-diastolic Dimension Research Articles

Predictors of Left Ventricular Mass Index One Year after Bioprosthetic Aortic Valve Replacement for Aortic Stenosis

Background and Aim of Study.To evaluate predictors of residual left ventricular hypertrophy (LVH) one year after surgical aortic valve replacement (SAVR) in patients with aortic stenosis and clarify the relationship between long-term outcomes and predictors. Methods. We retrospectively reviewed 141 patients who underwent SAVR with a bioprosthetic valve. Left ventricular dimensions and mass index were assessed using serial transthoracic echocardiography. The difference in time course and the pattern of left ventricular mass index (LVMI) regression between patients with and without residual LVH one year after surgery were evaluated. The factors associated with LVMI one year after SAVR and the prognostic impact of these predictors on long-term outcomes were analyzed. Results. Although LVMI one year after surgery showed a significant decrease in patients with and without LVH, greater preoperative LVMI and lesser extent of LVMI decrease resulted in high residual LVMI at one year after SAVR in patients with LVH. The preoperative left ventricular end-diastolic dimension index ( p = 0.027 ) and preoperative left atrial dimension ( p = 0.001 ) were significant determinants of LVMI at one year after SAVR. A cut-off value of 30 mm/m2 or greater for the left ventricular end-diastolic dimension index was optimal for predicting high LVMI one year after SAVR. Overall survival was significantly lower with a left ventricular end-diastolic dimension index ≥30 mm/m2 ( p = 0.017 , Log rank). Conclusions. High preoperative left ventricular end-diastolic dimension index and large left atrial dimension were associated with high LVMI one year after surgical aortic valve replacement. Preoperative left ventricular end-diastolic dimension index of >30 mm/m2 could predict adverse outcomes after surgical aortic valve replacement.

Three decades of reimplantation of the aortic valve-the Brussels experience.

Over the last three decades, the importance of native valve preservation has increasingly become evident. Valve-sparing root replacement procedures, such as the reimplantation or remodeling technique, are therefore being progressively used for aortic root replacement and/or aortic valve repair. Herein, we are summarizing our single-center experience with the reimplantation technique. We queried our prospective database for aortic valve repair and recruited all adult (≥18 years) patients who have undergone valve-sparing root replacement with the reimplantation technique between March 1998 and January 2022. We subcategorized the patients into three distinct groups: root aneurysm without aortic regurgitation (AR) (grade ≤1+), root aneurysm with AR (grade >1+) and isolated chronic AR (root <45 mm). Univariable logistic regression analysis was performed to identify variables of interest, which were further analyzed by multivariable Cox-regression analysis. Survival, freedom from valve reintervention, and freedom from recurrent regurgitation, were analyzed with the Kaplan-Meier method. A total of 652 patients were recruited for this study; 213 patients underwent reimplantation for aortic aneurysm without AR, 289 patients for aortic aneurysm with AR, and 150 patients with isolated AR. Cumulative survival was 95.4% (95% CI: 92.9-97.0%) after 5 years, 84.8% (80.0-88.5%) after 10 years, and 79.5% (73.3-84.5%) after 12 years, which was comparable to the age-matched Belgian population. Older age (HR 1.06, P≤0.001) and male gender (HR 2.1, P=0.02) were associated with late mortality. Freedom from reoperation on the aortic valve at 5 years was 96.2% (95% CI: 93.8-97.7%), and 90.4% (95% CI: 87.4-94.2%) at 12 years. Age (P=0.001) and preoperative left ventricular end-diastolic dimension (LVEDD) (P=0.03) were associated with late reoperation. Our long-term data supports our reimplantation approach as a viable option for aortic root aneurysms and/or aortic regurgitation, with long-term survival that mirrors that of the general population.

A New Modification for Anastomosing HeartMate 3 Apical Cuff for a Small Left Ventricle

<h3>Introduction</h3> A preoperative small left ventricular size has been associated with higher mortality and complications after left ventricular assist device (LVAD) implantation. The small left ventricle (LV) may result in repeated suction events and inflow obstruction, possibly leading to pump thrombosis and malfunction and thromboembolism. The inflow cannula length of HeartMate 3 is 22 mm, and the CT-measured protrusion depth of inflow cannula into the LV was 13.5 ± 1.0 mm in our previous HeartMate 3 series (16 patients). Based on the concept that making the protrusion depth shallow should decrease the risk for suction event, we adopted a hand-made apical cuff, whose actual thickness was 6mm, modified by stacking three layers of felt on the original PTFE felt during HeartMate 3 implantation for a small LV patient. Here, we report two cases in which this modified apical cuff was used. <h3>Case Report</h3> One patient is a 47-year-old woman with idiopathic dilated cardiomyopathy who underwent implantation of a HeartMate 3. Preoperative echocardiography showed a small left ventricular end-diastolic dimension (LVDd) of 49 mm. We anastomosed the described-above modified apical cuff in a core then sew technique. Postoperative LVDd was 30 mm and cardiac index was 2.7 L/min/m² under optimized pump setting. Another is a 58-year-old woman with dilated phase of hypertrophic cardiomyopathy who underwent implantation of a HeartMate 3. The preoperative LVDd of this patient was 48 mm. The same modified apical cuff was secured in a core then sew technique after resection of the intraventricular muscle through the apical coring hole. Postoperative LVDd was 37 mm and cardiac index was 2.2 L/min/m² under optimized pump setting. Both patients experienced no significant suction event or adverse events and are still waiting for heart transplantation as an outpatient. <h3>Summary</h3> This modified apical cuff is promising for achieving adequate pump performance of HeartMate 3 and possibly improving the outcomes of LVAD therapy in patients with the small LV.

The impact of left ventricular size on outcomes after centrifugal-flow left ventricular assist device implantation.

The influence of preoperative left ventricular size in outcomes following centrifugal-flow left ventricular assist device (LVAD) implantation has not been well characterized. A cohort of 313 patients who received a centrifugal-flow LVAD at a single institution was analysed. Using a maximally selected log-rank statistic, we investigated whether a left ventricular end-diastolic dimension (LVEDD) cut-off point was associated with worse outcomes. The cohort was then divided in 2 groups based on the LVEDD cut-off point. An LVEDD cut-off point of 59 mm was found to predict worse survival. Smaller LVEDD patients (≤59 mm, N = 52) were older and more likely to have a history of coronary artery disease compared those with a larger LVEDD (>59 mm, N = 261). Smaller LVEDD patients had lower survival compared to larger LVEDD patients (71% vs 85% at 1 year and 58% vs 80% at 2 years, P = 0.003). The need for temporary right ventricular mechanical support was significantly higher in the smaller LVEDD cohort (11.5% vs 1.9%, P = 0.002). Pump flows at time of discharge were lower in the smaller LVEDD group (3.8 vs 4.2 l/min, P = 0.005), who also had a higher incidence of late right ventricular failure (23% vs 12%, P = 0.02), higher rates of gastrointestinal bleeding (0.416 vs 0.256 events per patient-year, P = 0.025) and higher readmissions secondary to low flow alarms (0.429 vs 0.240 events per patient-year, P = 0.007). Multivariable analysis demonstrated that smaller LVEDD, older age, high BUN and high bilirubin levels were independent predictors of worse survival. In patients receiving a centrifugal-flow LVAD, smaller preoperative LVEDD (≤59 mm) was associated with lower survival and higher incidence of adverse outcomes.

Impact of transcatheter aortic valve replacement on renal function in patients with severe aortic stenosis

Objective: To explore the impact of transcatheter aortic valve replacement (TAVR) on renal function in patients with severe aortic stenosis. Methods: This is a single-center retrospective study. Consecutive patients with severe aortic valve stenosis and received TAVR in Zhongshan Hospital from December 2014 to December 2019 were included. The patients were divided into four groups according to the estimate glomerular filtration rate (eGFR) measured at one day before TAVR, namely eGFR>90 ml·min-1·1.73m-2 group, 60<eGFR≤90 ml·min-1·1.73m-2 group, 30<eGFR≤60 ml·min-1·1.73m-2 group and eGFR≤30 ml·min-1·1.73m-2 group. The patients were also divided into acute renal function recovery (AKR) group, acute kidney injury (AKI) group and no change in renal function group according to renal function changes at 72 hours after TAVR. AKR was defined as eGFR increased by more than 25% of the baseline value at 72 hours after TAVR, and AKI was defined as eGFR decreased more than 25% of the baseline value at 72 hours after TAVR. The clinical data of each group were compared, and multivariate logistic regression analysis was performed to analyze the determinants responsible for renal function changes after TAVR. Results: A total of 217 patients were enrolled in this study. The age was (76.7±7.4) years and there were 86 females. The Society of Thoracic Surgeons score was (9.5±5.8). The proportions achieved AKR after TAVR were 0, 30.2% (35/116), 58.6% (41/70) and 75.0% (9/12) respectively in eGFR>90 ml·min-1·1.73m-2 group, 60<eGFR≤90 ml·min-1·1.73m-2 group, 30<eGFR≤60 ml·min-1·1.73m-2 group and eGFR≤30 ml·min-1·1.73m-2 group. A total of 3 patients (1.4%) suffered AKI, including 2 patients in 30<eGFR≤60 ml·min-1·1.73m-2 group and 1 patient in 60<eGFR≤90 ml·min-1·1.73m-2 group. The incidence of AKI in eGFR<60 ml·min-1·1.73m-2 group was 2.4% (2/82). Among the 217 patients, AKR occurred in 85(39.2%) patients, 3(1.4%) experienced AKI and renal function remained unchanged in 129 (59.4%) patients post TAVR. Body mass index (BMI), left ventricular end diastolic dimension (LVEDD) and preoperative eGFR were statistically different between the 3 groups (P<0.05). Multivariate logistic regression analysis showed that BMI (OR=5.54, 95%CI 1.04-29.58, P=0.045), preoperative LVEDD (OR=1.22, 95%CI 1.09-1.38, P=0.001) and preoperative eGFR (OR=2.23, 95%CI 2.04-2.55, P=0.004) were associated with non-AKR post TAVR. Conclusions: After TAVR, most patients show no change or improvement of renal function. BMI, preoperative LVEDD and eGFR are related to renal function change after TAVR.

Multicenter experience: early outcome of mitral valve repair in patients with ischemic mitral regurgitation

Ischemic mitral regurgitation is associated with poor outcomes. The optimal surgical strategy for management of ischemic mitral regurgitation is still debated. The objective of this study was to evaluate the early mortality and morbidity of mitral valve repair in patients with ischemic mitral regurgitation undergoing coronary artery bypass grafting. We performed a retrospective, observational, cohort study on prospectively collected data on 136 consecutive coronary artery bypass graft patients with ischemic mitral regurgitation undergoing mitral valve repair between January 2016 and January 2020. Perioperative echocardiogram findings, operative procedures, and outcomes were analyzed. The overall mortality rate was 4.4%. Mitral valve repair with a low ejection fraction had a 4-fold increase in the risk of death compared to mitral valve repair with preserved ejection fraction > 30%. However, after adjusting for preoperative risk factors, the number of grafts was not an independent risk factor for mortality (odds ratio = 0.18, 95% confidence interval: 0.03-2.81, p = 0.84). Multivariable analysis showed that preoperative ejection fraction (odds ratio = 1.14, 95% confidence interval: 0.82-4.86, p < 0.01), preoperative left ventricular end-systolic dimension (odds ratio = 1.03, 95% confidence interval: 0.65-3.51, p < 0.01) and preoperative left ventricular end-diastolic dimension (odds ratio = 0.99, 95% confidence interval: 0.64-3.28, p = 0.04) were independent risk factors for mortality. Mitral valve repair can be performed safely concomitantly with coronary artery bypass grafting in patients with moderate, moderately severe, and severe ischemic mitral regurgitation.

Surgical and Transcatheter Treatments in Children with Congenital Aortic Stenosis.

For patients with congenital aortic valve stenosis (AVS), comprehensive analysis of surgical aortic valvuloplasty (SAV) or balloon dilation (BD) is scarce and remains controversial. This study reviewed AVS data (aortic peak gradient, aortic insufficiency, and survival and reoperation) for patients who were suitable for biventricular repair at our center in 2008 to 2018. Patients were categorized into two subgroups based on age (≤3 or >3 months). A total of 194 patients were treated, including 124 with SAV and 70 with BD. Resulting data revealed that residual aortic gradient at discharge was worse for BD (p = 0.001). While for patients younger than 3 months, the relief of AVS was comparable between the two groups (p = 0.624). There was no significant difference in time-related survival between the two groups (log-rank p = 0.644). Multivariate analysis demonstrated that preoperative left ventricular end-diastolic dimension predicted early death (p = 0.045). Survival in the two groups after 10 years was 96.8% in SAV and 95.7% in BD (p = 0.644). Freedom from reoperation after 10 years was 58.1% in SAV and 41.8% in BD patients (p = 0.01). There was no significant difference in freedom from reoperation between SAV and BD in patients younger than 3 months (p = 0.84). Multivariate analysis indicated that residual aortic peak gradient was predictive of reoperation (p = 0.038). Both methods achieved excellent survival outcomes at our center. SAV achieved superior gradient reduction and minimized the necessity for reoperation. For patients younger than 3 months, BD rivaled SAV both in aortic stenosis relief and freedom from reoperation.

A left ventricular end-diastolic dimension less than 6.0 cm is associated with mortality after implantation of an axial-flow pump

ObjectiveThe effects of having a lower left ventricular end-diastolic dimension before HeartMate II (Thoratec Corp, Pleasanton, Calif) left ventricular assist device implantation remain unclear. We analyzed our single-center data on HeartMate II implantation to determine whether having a lower left ventricular end-diastolic dimension preoperatively was associated with inferior outcomes. MethodsFrom November 2003 to March 2016, 393 patients with chronic heart failure underwent primary HeartMate II implantation. We compared the preoperative left ventricular end-diastolic dimension and associated survival outcomes of these patients to determine the left ventricular end-diastolic dimension cutoff for worse overall survival. Then, we compared the preoperative demographics, stroke rate, and mortality of patients with a left ventricular end-diastolic dimension above the cutoff for worse survival with those of patients with a left ventricular end-diastolic dimension below the cutoff. ResultsA Cox multivariate regression model showed that low left ventricular end-diastolic dimension was an independent predictor of mortality (hazard ratio, 1.49; P = .02). The Contal and O'Quigley method showed that overall survival postimplantation was decreased in patients with a left ventricular end-diastolic dimension less than 6.0 cm (n = 91). Kaplan–Meier analysis confirmed that the left ventricular end-diastolic dimension less than 6.0 cm group had lower overall survival than the left ventricular end-diastolic dimension 6.0 cm or greater group (P = .04). Furthermore, a competing-risk analysis showed that postoperative stroke was more common in the left ventricular end-diastolic dimension less than 6.0 cm group than in the left ventricular end-diastolic dimension 6.0 cm or greater group (P < .01). ConclusionsOverall survival was decreased and postoperative stroke was increased in HeartMate II recipients with a preoperative left ventricular end-diastolic dimension less than 6.0 cm. Future research should determine the left ventricular end-diastolic dimension cutoff values for safely implanting other support devices, and device designs should be improved to better accommodate the needs of patients with a limited left ventricle size.

Survival Prediction in Patients Undergoing Open-Heart Mitral Valve Operation After Previous Failed MitraClip Procedures

The objective of this study was to analyze the results of open heart mitral valve operations for survival prediction in patients with previously unsuccessful MitraClip procedures. Thirty-three consecutive patients who underwent mitral valve surgery in our institution were studied. At a median of 41 days, they had previously undergone one to five futile MitraClip implantations. At the time of their operations, patients were 72.6 ± 10.3 years old, and the calculated risk, using the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II, was a median of 26.5%. Individual outcomes were recorded, and all patients were monitored postoperatively. Thirty-day mortality was 9.1%, and the overall survival at 2.2 years was 60.6%. Seven cardiac-related and six noncardiac deaths occurred. Univariate survival regression models demonstrated a significant influence of the following variables on survival: EuroSCORE II (p = 0.0022), preoperative left ventricular end-diastolic dimension (p = 0.0052), left ventricular ejection fraction (p = 0.0249), coronary artery disease (p = 0.0385), and severe pulmonary hypertension (p = 0.0431). Survivors showed considerable improvements in their New York Heart Association class (p < 0.0001), left ventricular ejection fraction (p = 0.0080), grade of mitral regurgitation (p = 0.0350), and mitral valve area (p = 0.0486). Survival after mitral repair was not superior to survival after replacement. Indications for surgery after failed MitraClip procedures must be considered with the greatest of care. Variables predicting postoperative survival should be taken into account regarding the difficult decision as to whether to operate or not. Our data suggest that replacement of the pretreated mitral valve is probably the more reasonable concept rather than complex repairs. When the EuroSCORE II at the time of surgery exceeds 30%, conservative therapy is advisable.

Slope in preload recruitable stroke work relationship predicts survival after left ventriculoplasty and mitral repair in patients with idiopathic cardiomyopathy

BackgroundLeft ventriculoplasty (LVP) and mitral valve plasty (MVP) are sometimes effective for patients with idiopathic dilated cardiomyopathy (DCM) who are not eligible for heart transplantation. Strict patient selection is warranted for these controversial procedures. Methods and resultsThe subjects were 18 patients with idiopathic DCM and mitral regurgitation who had not been indicated for heart transplantation due to either older age or patient refusal, and who underwent LVP and MVP. Their mean age was 57±14 years and 50% were dependent on catecholamine infusion. The preload recruitable stroke work (PRSW) relationship and its slope (Mw) were estimated by a single-beat technique using transthoracic echocardiography. There were one 30-day mortality and six (33%) hospital deaths due to heart failure. The one-year survival rate was 50%. Left ventricular end-diastolic dimension (LVDd) decreased from 77±11 to 68±11mm (p=0.001) whereas the ejection fraction did not change. Preoperative Mw was significantly higher in one-year survivors than that in non-survivors (54±17ergcm−3103 vs. 31±10ergcm−3103, p=0.005). Preoperative LVDd was not different between the groups. The cut-off value of 42ergcm−3103 for Mw predicted one-year survival with high sensitivity (100%) and specificity (77%). ConclusionsMw, the slope in the PRSW relationship, may predict survival after LVP and MVP in patients with idiopathic DCM.

Surgical Management of Ischemic Mitral Regurgitation

Case presentation: A 62-year-old man visited his cardiologist describing a 6-month history of increasing fatigue and shortness of breath on exertion. His medical history included an inferoposterior myocardial infarction (MI) 3 years previously that was treated with drug-eluting stents to his left circumflex and right coronary arteries. The result of physical examination was remarkable for crackles audible throughout the lower half of both lung fields, an elevated jugular venous pulse to the angle of the jaw, and a grade 3/6 holosystolic murmur loudest at the apex with radiation to the left axilla. An echocardiogram revealed a left ventricular ejection fraction (LVEF) of 15% to 20%, severe mitral regurgitation (MR), and a left ventricular end systolic dimension of 70 mm. The patient underwent a repeat cardiac angiogram that revealed patent stents in the circumflex and right coronary arteries and no other significant stenoses. The decision was made to surgically correct the patient’s MR with a mitral valve operation. He was brought to the operating room, where he was given general anesthesia, and a transesophageal echocardiogram was performed. Examination of the mitral valve revealed poor leaflet coaptation with a degree of leaflet tethering that resulted in severe MR. Inasmuch as the valve leaflets appeared structurally normal, a mitral valve repair procedure using a complete rigid annuloplasty ring was performed. A postoperative echocardiogram revealed trace MR, and the patient experienced no postoperative complications. This patient is a typical example of a growing problem in our aging population, namely, ischemic mitral regurgitation (IMR). IMR clearly has a negative impact on survival in patients with coronary artery disease, even in patients with mild to moderate MR; greater degrees of MR portend an even worse prognosis.1 With almost a fifth of patients who experience an MI followed by the development of IMR,2,3 and over …

Surgical aortic valvuloplasty in children and adolescents with aortic regurgitation: Acute and intermediate effects on aortic valve function and left ventricular dimensions

Surgical aortic valvuloplasty is increasingly employed in the management of children and adolescents with aortic regurgitation, but the durability of this approach and factors associated with outcome are not well defined. From 1989 to 2005, a total of 81 patients younger than 19 years with moderate or severe aortic regurgitation underwent surgical aortic valvuloplasty. Aortic regurgitation was congenital in 20 cases, after treatment of aortic stenosis in 30, from other injuries to the aortic valve in 12, and from other causes in 19. Eighteen patients had moderate or severe aortic stenosis. Preoperative left ventricular end-diastolic dimension z score was 4.9 +/- 2.7. After surgical aortic valvuloplasty with various techniques, including pericardial leaflet augmentation in 80%, aortic regurgitation was improved in 77 patients and was mild or less in 68. Ten of 18 patients with moderate or severe aortic stenosis before repair had a decrease to mild, whereas 2 had progression from mild to moderate. Left ventricular end-diastolic dimension z score decreased by 2.9 +/- 2.1 (P < .001). During follow-up (median 4.7 years), 33 patients underwent aortic valve reinterventions, including aortic valve replacement in 25. Estimated freedoms from aortic valve replacement were 72% +/- 6% at 5 years and 54% +/- 9% at 7.5 years and were shorter in patients with moderate or severe aortic stenosis before surgical aortic valvuloplasty. Among surviving patients who did not undergo aortic valve replacement, aortic regurgitation at follow-up was moderate in 21 and trivial or mild in 34; left ventricular and aortic root dimensions were preserved. Surgical aortic valvuloplasty is a valid option with good intermediate results for children and adolescents with aortic regurgitation from a variety of causes, particularly for patients with less than moderate aortic stenosis.

Preoperative left ventricular dimensions predict reverse remodeling following restrictive mitral annuloplasty in ischemic mitral regurgitation☆

Ischemic mitral regurgitation can be treated with a restrictive mitral annuloplasty, with or without coronary revascularization. In this study, the extent of reverse remodeling of the left ventricle following this strategy is assessed, as well as the factors that influence it. Eighty-seven consecutive patients with ischemic mitral regurgitation and a mean ejection fraction of 32+/-10% underwent restrictive mitral annuloplasty (downsizing by two ring sizes, median ring size 26), with additional coronary revascularization in 75 patients. All underwent transthoracic echocardiography 18 months after surgery to assess residual mitral regurgitation, mitral valve gradient and left ventricular end-systolic and end-diastolic dimensions. Univariate and multivariate analysis was performed to identify predictors for reverse remodeling, defined as a 10% reduction in left ventricular dimension. Receiver-operating characteristic analysis was used to identify cut-off values for preoperative left ventricular dimensions in predicting reverse remodeling. Early mortality was 8.0% (seven patients, three non-cardiac), late mortality was 7.5% (six patients, four non-cardiac). There were two reoperations (redo annuloplasty), and four readmissions for heart failure. At 29 months follow-up, NYHA class improved from 3.0+/-0.9 to 1.3+/-0.5 (P<0.01). Mitral regurgitation grade decreased from 3.1+/-0.5 to 0.6+/-0.6 at 18 months, left ventricular end-systolic dimension decreased from 52+/-8 to 44+/-11 mm (P<0.01), and end-diastolic dimension from 64+/-8 to 58+/-10mm (P<0.01). Multivariate analysis identified preoperative left ventricular end-diastolic dimension as the single best factor in predicting occurrence of reverse remodeling. For end-systolic dimension, 51mm was the optimal cut-off value to predict reverse remodeling (specificity and sensitivity 81%, area under curve 0.85); for end-diastolic dimension, the cut-off value was 65mm (specificity and sensitivity 89%, area under curve 0.92). Stringent restrictive mitral annuloplasty with or without revascularization provides excellent clinical results with acceptable mortality. At 18 months follow-up, there is no significant residual mitral regurgitation. Reverse remodeling occurs in the majority of patients, but is limited by preoperative left ventricular dimensions. In patients with a left ventricular end-diastolic dimension exceeding 65mm, additional surgical procedures are necessary to try and obtain reverse remodeling in this subgroup.

Optimal timing of the Ross procedure in the management of chronic aortic incompetence in the young

The appropriate timing of intervention in patients with chronic aortic incompetence allows recovery of ventricular function. We sought to determine the optimal timing of the Ross procedure for chronic aortic incompetence in young patients. We retrospectively analysed case notes, and measured pre- and postoperative echocardiographic indexes of left ventricular function, in patients who had undergone the Ross procedure for chronic aortic incompetence. We found 21 patients with preoperative and postoperative data suitable for analysis. Their age at operation ranged from 5.6 to 26 years, with a median of 13.8 years, and the duration of follow-up was from 0.5 to 6.8 years, with a median of 2.4 years. The preoperative left ventricular end-diastolic dimension was converted to a z-score, and this was used as a threshold to divide the population. Using the threshold of a preoperative left ventricular z-score of more than 3 to divide the population did not show any difference in postoperative parameters of left ventricular function. Significant differences were found postoperatively, however, in both the left ventricular z-score and the ratio of left ventricular end-diastolic radius to posterior wall thickness in diastole, with a cutoff preoperative threshold z-score greater than 4. The increase in the ratio of left ventricular end-diastolic radius to the thickness of the posterior wall in diastole would suggest that there is disruption of left ventricular short axis architecture and myocardial contractile function when intervention is postponed. The significantly larger left ventricular dimension at end-diastole, despite the reduction in volume loading post surgery, may also demonstrate irreversible structural changes. Our data would suggest that recovery of left ventricular function is less likely when the left ventricular z-score has reached the value of 4, and that, ideally, intervention should be performed when the z-score approaches or exceeds 3.