Relationship of ventricular longitudinal function to contractile reserve in patients with mitral regurgitation

Does high dose statin pretreatment affect global strains in patients undergoing valve replacement

Purpose

To study the effect of rosuvastatin 40 mg (initiated 7 days prior to surgery) in patients undergoing valve replacement (VR) for rheumatic mitral valve disease on left ventricular (LV) strain and biomarker release kinetics.

Methods

In this randomized study, cardiac biomarkers viz. troponin I (TnI), Creatine kinase MB (CK-MB), N-terminal pro B-type natriuretic peptide (NTPBNP) were measured before surgery; and 8, 24 and 48 h postoperatively. Global LV (circumferential, global circumferential strain (GCS); longitudinal, GLS; radial, global radial strain (GRS)) strains were measured preoperatively; and 48 h and 30 days postoperatively.

Results

Following VR, Global Longitudinal Strain (GLS), Global Circumferential Strain (GCS) and Global Radial Strain (GRS) declined at 48 h in both statin loaded (SL) and non loaded (NL) groups. The %decline in strain was significantly lower in SL group (% change in GLS 35.8% vs 38.8%, GCS 34% vs 44.1%, GRS 45.7% vs 52.6%; p < 0.001).All strain values improved at 30 days with higher improvement in SL group (GLS -15.92 ± 2.00% vs -12.6 ± 1.66%, GCS -15.12 ± 2.93% vs -13.04 ± 2.44%; GRS 22.12 ± 6.85% vs 19.32 ± 6.48%). While TnI, CKMB, NTPBNP increased following surgery, values at 8, 24 and 48 h were lower in the SL vs. NL group. Mean change (baseline to peak biomarker value) was also significantly lower in SL group.The SL group had shorter hospital and Intensive Care Unit (ICU) stay. On Receiver Operating Characteristic Curve (ROC) analysis, baseline GCS ≤ 14% best predicted postoperative 30 day Left Ventricular Ejection Fraction (LVEF) ≤ 50%.

Conclusion

Pre-operative high dose rosuvastatin was "cardioprotective" with favorable effect on LV global strain and release kinetics of biomarkers. These cut-offs (described for the first time for rheumatic VR) can be used as prognostic predictors.

Stress echocardiography in valvular heart disease

Valvular heart disease (VHD) has been a significant health problem, particularly in developed countries, in relation to the aging population. Recent developments in the management of VHD require a more accurate assessment of disease severity to determine the need for transcatheter interventions or open heart surgery. Stress echocardiography is a crucial imaging modality for identifying the underlying pathology of VHD. Optimal administration of exercise or intravenous drugs may reveal hemodynamic abnormalities under stress without posing an invasive risk. Therefore, the implementation of stress echocardiography is recommended for determining interventional indications and risk stratification in mitral regurgitation and aortic stenosis. In addition, recent evidence has accumulated regarding the usefulness of stress echocardiography in various conditions including mitral stenosis, aortic regurgitation, and post-interventional VHD. Here, we summarize the current evidence and future perspectives on stress echocardiography in VHD.

Predictors of Left Ventricular Dysfunction After Surgery for Degenerative Mitral Regurgitation

BACKGROUND

This study was performed to determine whether strain can supplement the ability of left ventricular (LV) ejection fraction (LVEF) to predict postoperative ventricular dysfunction in patients undergoing mitral valve surgery for degenerative mitral regurgitation (DMR).

METHODS

From 2004 to 2017, 520 patients with an LVEF of 60% or more underwent mitral valve surgery (98% repair) for DMR. All patients had preoperative, predischarge, and follow-up (mean, 5.0 ± 3.6 years) echocardiograms. Speckle tracking was performed in 119 of 520 patients (22.9%) to determine LV strain, right ventricular free-wall strain, and left atrial longitudinal strain. Multivariate logistic and Cox regression models were used in this subgroup to evaluate associations with early postoperative LV dysfunction and medium-term overall survival, respectively.

RESULTS

Median preoperative LVEF of the entire cohort was 65%. Based on predischarge echocardiogram, 449 patients (86.3%) maintained postoperative LVEF of 50% or greater. Seventy-one patients (13.7%) had a predischarge LVEF of less than 50%, 49 (9.4%) had a predischarge LVEF of 40% to 49%, and 22 (4.2% overall) had a predischarge LVEF of less than 40%. Abnormal preoperative LV, right ventricular, and left atrial strain measurements were significantly associated with the development of postoperative LV dysfunction, but preoperative hemodynamic and non-strain echo parameters did not vary enough in absolute values to be clinically useful as predictors of postoperative LV dysfunction.

CONCLUSIONS

Preoperative strain measurements in DMR patients were significantly associated with superior capabilities of detecting underlying LV dysfunction despite preserved preoperative LVEF. Strain analysis may serve as another marker for optimal timing of surgical intervention in DMR patients.

Exercise capacity in asymptomatic patients with significant primary mitral regurgitation: independent effect of global longitudinal left ventricular strain

Background

Despite preserved left ventricular ejection fraction (LVEF), patients with significant primary mitral regurgitation (MR) often have reduced exercise capacity. In asymptomatic patients with ≥3+ primary MR undergoing rest-stress echocardiography (RSE), we sought to evaluate the incremental impact of left ventricular global longitudinal strain (LV-GLS) on exercise capacity.

Methods

A total of 660 asymptomatic patients with ≥3+ primary MR, non-dilated LV and LVEF ≥60% (mean age, 57±14 years, 66% men, body mass index or BMI 25±4 kg/m²) who underwent RSE at our center between 2001 and 2013 were included. Standard RSE data were obtained. Average resting LV-GLS was measured using Velocity Vector Imaging.

Results

Mean mitral effective regurgitant orifice, resting right ventricular systolic pressure (RVSP) and LV-GLS were 0.45±0.2 cm², 31±12 mmHg and -21.7%±2%, respectively; 28% had flail mitral leaflet. Mean metabolic equivalents (METs) and post-stress RVSP were 9.9±3, and 46±15 mmHg; 28% achieved <100% age-gender predicted METs. No patient had ischemia or significant arrhythmias. On logistic regression, resting LV-GLS [odds ratio (OR), 1.40, 95% confidence interval (CI): 1.21-1.55, BMI (OR, 1.11, 95% CI: 1.06-1.17)] and resting RVSP 1.22 (1.02-1.49) were independent predictors of exercise capacity. Area under the curve for association between 100% age-gender predicted METs and various factors were as follows: (I) BMI (0.60, 95% CI: 0.55-0.65, P<0.001); (II) resting RVSP (0.57, 95% CI: 0.52-0.62, P=0.006) and LV-GLS (0.66, 95% CI: 0.61-0.70, P<0.001).

Conclusions

In asymptomatic patients with ≥3+ primary MR, non-dilated LV and preserved LVEF, LV-GLS is independently associated with exercise capacity, beyond known predictors.

Practical guidance for the implementation of stress echocardiography

Exercise stress testing has been widely undertaken for the diagnosis of heart diseases. The accurate assessment of clinical conditions can be conducted by comparing the findings obtained from the results of stress echocardiography with the changes in the blood/heart rate and electrocardiograms. Numerous overseas studies have reported the utility of stress echocardiography in diagnosing myocardial ischemia; in Japan, the use of this modality for this purpose was included in the national health insurance reimbursable list in 2012. Nevertheless, stress echocardiography is far from being a widespread practice in Japan. This might be due to insufficient equipment (e.g., ergometers, space for test implementation) at each medical institution, shortage of technicians and sonographers who are well experienced and who are responsible for obtaining images during stress testing. The other possible reasons include the limited evidence available in Japan and the lack of a standardized testing protocol. Further dissemination of the practice of exercise stress echocardiography in this country is deemed necessary to establish satisfactory evidence for the use of stress echocardiography in the Japanese population. To this end, efforts are underway to develop a standardized protocol and report format to be adopted throughout Japan. We here present a guideline created by the Guideline Development Committee of the Japanese Society of Echocardiography that describes safe and effective stress echocardiography protocols and report formats. The readers are encouraged to perform exercise stress echocardiography using the proposed template for consensus document and report attached to this guideline.

Isoflurane's Effect on Intraoperative Systolic Left Ventricular Performance in Cardiac Valve Surgery Patients

BACKGROUND

Isoflurane, a common anesthetic for cardiac surgery, reduced myocardial contractility in many experimental studies, few studies have determined isoflurane's direct impact on the left ventricular (LV) contractile function during cardiac surgery. We determined whether isoflurane dose-dependently reduces the peak systolic velocity of the lateral mitral annulus in tissue Doppler imaging (S') in patients undergoing cardiac surgery.

METHODS

During isoflurane-supplemented remifentanil-based anesthesia for patients undergoing cardiac surgery with preoperative LV ejection fraction greater than 50% (n = 20), we analyzed the changes of S' at each isoflurane dose increment (1.0, 1.5, and 2.0 minimum alveolar concentration [MAC]: T1, T2, and T3, respectively) with a fixed remifentanil dosage (1.0 μg/min/kg) by using transesophageal echocardiography.

RESULTS

Mean S' values (95% confidence interval [CI]) at T1, T2, and T3 were 10.5 (8.8-12.2), 9.5 (8.3-10.8), and 8.4 (7.3-9.5) cm/s, respectively (P < 0.001 in multivariate analysis of variance test). Their mean differences at T1 vs. T2, T2 vs. T3, and T1 vs. T3 were -1.0 (-1.6, -0.3), -1.1 (-1.7, -0.6), and -2.1 (-3.1, -1.1) cm/s, respectively. Phenylephrine infusion rates were significantly increased (0.26, 0.22, and 0.47 μg/kg/min at T1, T2, and T3, respectively, P < 0.001).

CONCLUSION

Isoflurane increments (1.0-2.0 MAC) dose-dependently reduced LV systolic long-axis performance during cardiac surgeries with a preserved preoperative systolic function.

Imaging 4D morphology and dynamics of mitral annulus in humans using cardiac cine MR feature tracking

Feature tracking in cine cardiac magnetic resonance (CMR) is a quantitative technique to assess heart structure and function. We investigated 4-dimensional (4D) dynamics and morphology of the mitral annulus (MA) using a novel tracking system based on radially rotational long-axis cine CMR series. A total of 30 normal controls and patients with mitral regurgitation were enrolled. The spatiotemporal changes of the MA were characterized by an in-house developed program. Dynamic and morphological parameters extracted from all 18 radial slices were used as references and were compared with those from subsequently generated sub-datasets with different degrees of sparsity. An excellent agreement was found among all datasets including routine 2-, 3- and 4-chamber views for MA dynamics such as peak systolic velocity (Sm) and mitral annular plane systolic excursion (MAPSE). MA morphology for size and shape was addressed adequately by as few as 6 radial slices, but poorly by only three routine views. Patients with regurgitation showed significantly reduced mitral dynamics and mild annular deformation, which was consistent between three routine views and 18 reference slices. In conclusion, feature tracking cine CMR provided a comprehensive and distinctive profile for 4D MA dynamics and morphology, which may help in studying different cardiac diseases.

Exercise Testing in Mitral Regurgitation

Mitral regurgitation (MR) is the second most common valvular heart disease referred for corrective surgery. Diagnostic and management dilemmas are not uncommon when dealing with MR patients. Exercise testing plays an important role in sorting out some of these clinical challenges. In primary asymptomatic MR, exercise testing allows symptom assessment, confident link of symptoms to valve disease severity, safe deferral of surgery for the next 1-year in patients with preserved exercise capacity, insights into the mechanism of exercise-induced dyspnea and helps in individual risk stratification. Moreover, exercise testing in the form of exercise stress echocardiography is also useful in the evaluation of patients with secondary ischemic MR for risk stratification as well as for the detection of patients with moderate ischemic MR in whom mitral valve repair at the time of surgical revascularization may add benefit.

Incremental Prognostic Value of Global Longitudinal Strain and 18F-Fludeoxyglucose Positron Emission Tomography in Patients With Systemic Sarcoidosis

In independent studies, abnormal global longitudinal strain (GLS) and myocardial inflammation or scar detected by 18F-fludeoxyglucose positron emission tomography (FDG-PET) are associated with poor prognosis among patients with high likelihood for cardiac sarcoidosis. However, commonly used imaging modalities have not been evaluated in the same population. Our goals were to examine the relation between GLS and FDG-PET, and to evaluate the incremental prognostic value of these imaging techniques for predicting major adverse cardiac events (MACE) in patients suspected to have cardiac sarcoidosis. We identified patients with systemic sarcoidosis who underwent an echocardiogram and FDG-PET within 60 days. Regional strain (average of base, mid, and apical segmental strains from each of 6 wall regions) was calculated and compared with regional FDG-PET findings. The associations among GLS, FDG-PET findings, and MACE (defined as death, ventricular tachycardia, heart failure hospitalization, or transplantation) were evaluated using a Cox model. Of 84 patients, 51 had abnormal FDG-PET. GLS was impaired in patients with abnormal versus normal FDG-PET (-14.2 ± 4.7% vs -17.9 ± 3.5%, p <0.01). After adjusting for clinical risk factors, both GLS and the number of segments with abnormal perfusion and metabolism on FDG-PET were associated with adverse cardiac events (p <0.01 for both). In conclusion, GLS and regional LS are impaired in patients with abnormal perfusion and metabolism detected using FDG-PET. Additionally, both GLS and abnormal FDG-PET have incremental prognostic value for predicting MACE in patients with systemic sarcoidosis.

Echocardiographic Assessment of Left Ventricular Function in Healthy Horses and in Horses with Heart Disease Using Pulsed-Wave Tissue Doppler Imaging

Background

Assessment of left ventricular (LV) function by tissue Doppler imaging (TDI) is not well established in horses with heart disease.

Objectives

To describe the use of pulsed‐wave (PW) TDI for the assessment of LV function, establish reference intervals, investigate effects of mitral regurgitation (MR), aortic regurgitation (AR), and primary myocardial disease (MD), and provide proof of concept for the use of PW TDI in Warmblood horses with heart disease.

Animals

Thirty healthy horses, 38 horses with MR, 25 with AR, 8 with MD.

Methods

Echocardiograms were retrospectively analyzed. Reference intervals were calculated. PW TDI indices of healthy horses and horses with MR, AR, and MD were compared by one‐way ANOVA and Dunnett's test.

Results

A complete set of PW TDI variables could be obtained in 94 of 101 horses. Variables corresponding to isovolumic intervals were most difficult to measure. Valvular regurgitation influenced variables describing isovolumic contraction and ejection. Horses with MD had significantly shortened ET_m (−118.5 [−154.1 to −82.9] ms; mean difference [95% CI of difference of means]), increased PEP_m/ET_m (0.11 [0.05 to 0.17]), prolonged IMP_m (0.28 [0.18 to 0.37]), increased S₁ (8.9 [5.2 to 12.6] cm/s), and decreased E₁ (−2.6 [−4.7 to −0.5] cm/s), E_m (−14.2 [−19.9 to −8.5] cm/s), and E_m/A_m ratio (−1.6 [−2.6 to −0.6]).

Conclusions and Clinical Importance

Pulsed‐wave TDI might be useful for detection of LV dysfunction in horses with primary MD. The clinical value of TDI in horses with MR and AR remains uncertain.

Prognostic Importance of Exercise Brain Natriuretic Peptide in Asymptomatic Chronic Organic Severe Mitral Regurgitation: An Observational Study

BACKGROUND

The optimal timing of surgery in patients with chronic organic severe mitral regurgitation (MR) continues to be debated, especially for those who are asymptomatic. The aim of the study was to determine independent and additive prognostic value of exercise brain natriuretic peptide (eBNP) in patients with severe asymptomatic MR and normal left ventricular ejection fraction (LVEF).

METHODS

Two hundred twenty-three consecutive patients with severe MR defined by effective regurgitant orifice (ERO) area ≥ 40 mm² and/or residual volume ≥ 60 mL, LVEF > 60%, and normal LV end-systolic diameter < 40 mm underwent symptom limited exercise treadmill test (TMT). Echocardiography was done immediately after exercise. Data were obtained within 3 minutes of peak exercise. BNP levels were assessed before echo (after 30 minutes of supine rest) and at exercise (i.e., within the 3 minutes of the end of effort). Patients were followed up every 3 months up to 15 months for major adverse cardiac events (MACEs) (cardiovascular death, need for mitral valve surgery and hospitalization for acute pulmonary edema or heart failure).

RESULTS

Mean age was 31.2 ± 9 years (range: 18 - 40) with majority being male (n = 153; 68%). Etiologies were rheumatic (n = 201; 90%), mitral valve prolapse (n = 17; 7.6%) and hypertrophic cardiomyopathy (n = 5; 2.4%). BNP level significantly increased from rest (65.24 ± 43.92 pg/mL; median: 43.5 pg/mL) to exercise (100.24 ± 98.24 pg/mL; median: 66.5 pg/mL; P < 0.001). Patients were divided into three tertiles according to eBNP levels (T₁ = 15 - 44; T₂ = 45 - 104; T₃ = 105 - 400). There was trend for significantly lower exercise time in T₃. During TMT, 66 (29.5%) stopped exercise due to dyspnea. They had similar resting BNP level compared with others but had significantly higher eBNP level (136 ± 109.7 pg/mL vs. 84.88 ± 90.2 pg/mL; P < 0.001). During follow-up (15 months), MACE occurred in 83 patients (37.2%): mitral valve replacement (MVR) in 59 patients (symptomatic: 43; LV dilatation or dysfunction: 9; both symptoms and dilatation/dysfunction: 7), 17 hospitalizations for congestive heart failure, five patients developing acute pulmonary edema and atrial fibrillation in remaining two patients. This was 7.6%, 35% and 69% in T₁, T₂ and T₃, respectively and had significantly higher eBNP level than without any event (165 ± 119 pg/mL vs. 57 ± 48 pg/mL; P < 0.001). Using receiver operating characteristic curve analysis, the best cut-off value of eBNP level to predict cardiac events was 90 pg/mL (sensitivity: 75%; specificity: 88.6%; positive predictive value: 79%; negative predictive value: 83.9%).

CONCLUSION

In asymptomatic patients, eBNP level provides incremental prognostic value beyond echocardiographic data and those with elevated eBNP should be considered at high risk for reduced event-free survival and might be considered for early MVR.

Principles of transthoracic echocardiographic evaluation

Transthoracic echocardiography is the most widely used imaging test in cardiology. Although completely noninvasive, transthoracic echocardiography has a well-established role in the diagnosis of numerous cardiovascular diseases, and also provides critical qualitative and quantitative information on their prognosis and pathophysiological processes. The aim of this Review is to outline the broad principles of transthoracic echocardiography, including the traditional techniques of two-dimensional, colour, and spectral Doppler echocardiography, and newly developed advances including tissue Doppler, myocardial deformation imaging, torsion, stress echocardiography, contrast and three-dimensional echocardiography. The advantages and disadvantages, clinical application, prognostic value, and salient research findings of each modality are described. Advances in complex imaging techniques are expected to continue unabated, and this Review highlights technical improvements that will influence the diagnosis and improve our understanding of cardiovascular function and disease.

Usefulness of conventional and tissue Doppler echocardiography to predict congestive heart failure in dogs with myxomatous mitral valve disease

Background

Systolic and diastolic functions have been evaluated to predict outcome in congestive heart failure (CHF). Recently, tissue Doppler imaging (TDI) has become useful for the estimation of myocardial function in cardiac diseases of humans and animals.

Objective

This study was designed to assess whether myocardial function as assessed by TDI is associated with the occurrence of CHF in dogs with myxomatous mitral valve disease (MMVD) and whether additional information is gained over conventional Doppler variables.

Animals

Forty‐one privately owned dogs (15 healthy dogs and 26 dogs with MMVD) were included. Dogs with MMVD were divided into non‐CHF (n = 10) and CHF groups (n = 16).

Methods

Conventional echocardiographic examinations were performed. In addition, TDI‐derived variables, including radial and longitudinal velocities, strain, and strain rate were assessed.

Results

Several (12 of 47, 26%) conventional and tissue Doppler echocardiography variables were significant predictors of CHF in a univariate analysis (P < .05). However, TDI‐derived E/E_{m sept} was the only load‐independent significant predictor of CHF (P < .05) after multivariate logistic regression analysis. The E/E_{m sept} cut‐off value of >18.7 had a sensitivity of 56% and specificity of 90% in predicting CHF in dogs with MMVD.

Conclusions and Clinical Importance

The combination of TDI of the mitral annulus and mitral inflow velocity provided better estimates of diastolic dysfunction in dogs with MMVD and CHF. Additional study is warranted to assess TDI‐derived E/E_{m sept}, an index of diastolic function that could contribute to the management of dogs with MMVD and CHF.

The cardiac muscle duplex as a method to study myocardial heterogeneity

This paper reviews the development and application of paired muscle preparations, called duplex, for the investigation of mechanisms and consequences of intra-myocardial electro-mechanical heterogeneity. We illustrate the utility of the underlying combined experimental and computational approach for conceptual development and integration of basic science insight with clinically relevant settings, using previously published and new data. Directions for further study are identified.

Surgical timing of degenerative mitral regurgitation: what to consider

Severe primary mitral regurgitation (MR) is a progressive condition which engenders significant mortality and morbidity if left untreated. The optimal timing of surgery in patients with MR of degenerative origin continues to be debated, especially for those who are asymptomatic. Apart from symptoms, current authoritative guidelines recommend intervention when there is incipient left ventricular dysfunction, pulmonary hypertension or new onset atrial fibrillation. This review focuses on the asymptomatic subject with severe MR, and examines contemporary clinical decision-making and management strategies, including the 2012 European guidelines on valvular heart disease. We discuss the rationale for risk stratifying the asymptomatic individual, and highlight current and novel diagnostic tools that may have a useful role, with an emphasis on echocardiographic imaging.

Exercise tolerance in asymptomatic patients with moderate-severe valvular heart disease and preserved ejection fraction

INTRODUCTION

For asymptomatic patients with moderate-severe valvular heart disease, in whom symptoms may be obscured, objective exercise tolerance measures are warranted for decisions concerning physical activities and surgical treatment.

MATERIAL AND METHODS

We compared 61 patients (39 with aortic stenosis, 22 with aortic or mitral regurgitation) to 23 controls without valvular heart disease but with indications for stress testing. All participants underwent cardiopulmonary function testing and dobutamine stress echocardiography. Blood was drawn before as well as after bicycle stress to assess high-sensitivity cardiac troponin T (hscTnT). Patients who underwent surgery were re-evaluated 1.5 ±0.9 years after the operation.

RESULTS

Conventional bicycle test following guideline criteria revealed a pathologic result in 26% of the patients, whereas spiroergometry showed an objectively reduced exercise tolerance in 59%, reaching a prognostically relevant feature in 39%. Stress echocardiography detected a reduced systolic reserve in 33% and elevated filling pressures in 62%. These abnormalities were significantly less present in the control group (4, 17, 9, 9, 4% respectively, p < 0.05 each). Baseline hscTnT detected patients with the prognostically important feature of reduced exercise tolerance (area under the curve 0.689 (95% CI: 0.546-0.831), p = 0.015). Objective preoperative exercise tolerance predicted sustained cardiocirculatory and myocardial dysfunction postoperatively.

CONCLUSIONS

Cardiopulmonary function testing and dobutamine stress echocardiography identify exercise intolerance in patients with asymptomatic valvular heart disease beyond stress-test criteria recommended in recent guidelines. High-sensitivity cardiac troponin I may be of additional value. Results of these tests presage post-operative function.

Incremental value of global longitudinal strain for predicting early outcome after cardiac surgery

AIMS

Global longitudinal strain (GLS) seems accurate for detecting subclinical myocardial dysfunction, and may therefore be used to improve risk stratification for cardiac surgery.

METHODS AND RESULTS

Longitudinal strain (by two-dimensional speckle tracking) was computed in 425 patients [mean age 67 ± 13 years, 69% male, left ventricular ejection fraction (LVEF) 51 ± 13%] referred for cardiac surgery [isolated coronary artery bypass graft (CABG) (n = 155), aortic valve surgery (n = 174), mitral surgery (n = 96)]. GLS (global-ε) was assessed for predicting early postoperative death. Despite a fair correlation between LVEF and global strain (r = -0.73, P < 0.0001), 40% of patients with preserved LVEF (defined as LVEF ≥50%) had abnormal global-ε (defined as global-ε >-16%): -12.8 ± 1.7%, range -15% to -8%. In patients with preserved LVEF, NT-proBNP level (983 vs. 541 pg/mL, P = 0.03), heart failure symptoms (NYHA class, 2.2 ± 0.9 vs. 1.9 ± 0.9, P = 0.02), and the need for prolonged (>48 h) inotropic support after surgery (33.3 vs. 21.2%, P = 0.03) were greater when global-ε was impaired. Importantly, despite similar EuroSCORE (9.7 ± 12 vs. 7.7 ± 9%, P = 0.2 for EuroSCORE I and 4.2 ± 6.2 vs. 3.4 ± 4.9%, P = 0.4 for EuroSCORE II), the rate of postoperative death was 2.4-fold (11.8 vs. 4.9%, P = 0.04) in patients with preserved LVEF when global-ε was impaired. Multivariate analysis showed that global-ε is an independent predictor for early postoperative mortality [odds ratio = 1.10 (1.01-1.21)] after adjustment to EuroSCORE.

CONCLUSION

GLS has an incremental value over LVEF for risk stratification in patients referred for cardiac surgery.

Left ventricular long-axis function: reference values of the mitral annular plane systolic excursion in 558 healthy children and calculation of z-score values

BACKGROUND

Longitudinal myocardial function has gained more interest in the last years. The mitral annular plane systolic excursion (MAPSE) is an echocardiographic measurement to assess left ventricular (LV) long-axis function in adults. The aim of this study was to evaluate MAPSE values in a healthy pediatric population and to propose reference values.

METHODS

A prospective study was conducted in a group of 558 healthy children and adolescents (age day 1 to 18 years) (body surface area [BSA] 0.18-2.21 m(2)). We determined the effects of age and BSA on MAPSE values and a possible correlation of MAPSE values with LV ejection fraction values.

RESULTS

The MAPSE ranged from a mean of 0.57 cm (z-score ±2: 0.38-0.76 cm) in neonates to 1.63 cm (z-score ±2: 1.31-1.95 cm) in 18-year-old adolescents. The MAPSE values showed a positive correlation with age (r = 0.87, P < .001) and BSA (r = 0.89, P < .001) with a nonlinear course. There was no significant difference in MAPSE values between females or males. A positive correlation was found between MAPSE values and LV ejection fraction values (r = 0.28, P < .001).

CONCLUSIONS

Z-scores of MAPSE values were calculated, and percentile charts were established to serve as reference data in patients with congenital heart disease or heart failure in the future.

Early prediction of left ventricular systolic dysfunction in patients of asymptomatic chronic severe rheumatic mitral regurgitation using tissue Doppler and strain rate imaging

AIMS

Identification of subclinical left ventricular (LV) dysfunction in patients with rheumatic mitral regurgitation (MR) facilitates optimal surgical results and better postoperative LV function. This study is designed to assess the role of tissue Doppler and strain rate (SR) imaging in early detection of LV systolic dysfunction in patients with asymptomatic chronic severe MR.

METHODS AND RESULTS

Patients were studied under four groups. Group I: Normal subject (n = 25). Group II: Patients with chronic severe MR with ejection fraction (EF) > 60% and end-systolic dimension (ESD) ≤ 40 mm (n=23). Group III: Patients with chronic severe MR with EF ≥ 60% and ESD 41-50 mm (n = 27). Group IV: Patients with chronic severe MR with EF < 60% with any ESDs (n = 25). With decrease in EF and increase in ESD there was decrease in systolic velocity and increased in precontraction time and contraction time was noted. The tissue Doppler systolic indices between groups were statistically significant P < 0.05 and showed significant correlation value r = 0.45 between groups. Strain (S) and SR significantly decreased with decrease in EF and increase in ESD P < 0.05, r = 0.45 between different groups.

CONCLUSION

Our study showed significant correlation between tissue Doppler systolic indices and SR imaging with EF and ESD.

Application of Mitral Annular Systolic Displacements and Velocities for the Evaluation of Left Ventricular Systolic Function and Reserve

Background

Mitral annular systolic displacement from M-mode echocardiography and velocity from tissue Doppler imaging reflect subendocardial longitudinal systolic LV performance and may precede radial abnormalities. The aim of this study is to evaluate the utility of mitral annular systolic displacement (D) and velocity (V) during dobutamine stress echocardiography (DSE) in detecting left ventricular (LV) functional reserve and wall motion abnormality (WMA).

Methods and Results

Fifty-nine subjects, 15 with resting WMA, underwent DSE and measurement of mitral systolic (D) and (V) before and immediately after DSE. Annular septal (D) was lower in those with WMA than in those without, at rest 10.5 ± 4 cm versus 13.2 ± 2 cm, p = 0.015, and after DSE, 11.7 ± 3.8 cm versus 14 ± 2.25 cm, p = 0.036, but without significant change after stress. Annular systolic (V) at rest with WMA was 9.7 ± 1.8 cm/sec and similar to those without, 11.25 ± 2.7 cm/sec. In both groups the velocity increased after DSE, 14.5 ± 4.5 cm/sec, p = 0.025 with WMA and 17.8 ± 3.2 cm/sec, p = 1.99 x 10^-10 in those without WMA. Velocities after DSE were lower in those with WMA, p = 2.25 x 10^-6.

Conclusions

To evaluate LV systolic performance mitral annular systolic longitudinal displacement is valuable at rest, but for assessment of LV functional reserve after stress velocities are better.

Novel methods to assess heart valve disease

Optimal timing of surgery for heart valve disease relies on the accurate assessment of symptoms, lesion severity, cardiac function and the risks of disease progression. Recent studies suggest potential roles for new echocardiographic techniques, including tissue Doppler and strain imaging at rest or after exercise stress, cardiac magnetic resonance imaging and biomarkers such as B-type natriuretic peptide. These techniques may identify patients at higher risk of symptomatic deterioration or adverse clinical events, and improve the cost-effectiveness and reliability of follow-up.

Importance of left ventricular longitudinal function and functional reserve in patients with degenerative mitral regurgitation: assessment by two-dimensional speckle tracking

BACKGROUND

The aim of this study was to determine whether two-dimensional speckle tracking of longitudinal myocardial deformation can detect limited contractile reserve during exercise in patients with asymptomatic degenerative mitral regurgitation (MR).

METHODS

Seventy-one patients with degenerative MR and normal left ventricular (LV) ejection fractions underwent quantitative exercise echocardiography.

RESULTS

Compared with 23 normal subjects matched for age and sex, LV volumes were greater in patients with MR. At rest, global longitudinal strain (GLS) was lower in patients, indicating subclinical LV dysfunction. During exercise, the extent and the magnitude of changes in GLS were larger in controls than in patients with MR. On multivariate regression analysis, left atrial volume at rest and changes in GLS at peak exercise were independently associated with changes in LV ejection fraction.

CONCLUSION

In asymptomatic patients with degenerative MR, subnormal LV function can be reliably identified by two-dimensional strain imaging. Limited exercise LV longitudinal contractile recruitment during exercise predicts postoperative LV dysfunction.

Evaluation of left ventricular short- and long-axis function in severe mitral regurgitation using 2-dimensional strain echocardiography

BACKGROUND

Few data exist on the changes in left ventricular (LV) short- and long-axis function and their usefulness as markers of LV contractile function in patients with chronic, severe mitral regurgitation (MR).

METHODS

We studied 59 patients who had severe MR with an ejection fraction > or =50% and 34 healthy controls. Speckle tracking imaging was performed to measure peak systolic radial (SR(R)), circumferential (SR(C)), and longitudinal strain rates (SR(L)). In all patients, the peak rate of LV pressure rise (peak dP/dt) was measured using a micromanometer-tipped catheter. The patients were subdivided into patients with preserved (group 1, peak dP/dt > or =1,300 mm Hg/s [n = 30]) and depressed (group 2 [n = 29]) contractile function.

RESULTS

SR(L) was significantly depressed in groups 1 and 2 when compared with the control group, but there was no difference between groups 1 and 2. In contrast, SR(R) and SR(C) were depressed only in group 2, whereas there were no differences between the control group and group 1. SR(R) and SR(C) correlated well with peak dP/dt (r = 0.71, P <.001 and r = -0.63, P <.001, respectively), whereas SR(L) did not. These findings suggest that LV long-axis function becomes depressed earlier than short-axis function in the chronic remodeling process.

CONCLUSIONS

Left ventricular short-axis function is a useful marker of LV contractility in patients with chronic, severe MR. Left ventricular long-axis function becomes depressed earlier in the chronic remodeling process. Therefore, evaluation of short-axis as well as long-axis function might be important for better assessment of LV contractile function in these patients.

Advances in the cardiovascular assessment of patients with chronic kidney disease

Cardiovascular mortality is grossly elevated in patients with chronic kidney disease (CKD), and is associated with a wide variety of structural and functional abnormalities. These issues have driven additional attempts to further characterise these abnormalities to elucidate the pathophysiology involved, assess individual risk and/or target and monitor therapies specifically directed at the cardiovascular (CV) system. This review aims to assess the techniques that are currently available for the study of the CV system. This includes conventional assessments of the whole CV system from heart to peripheral microcirculation (although not deal with VC assessment), as well as the key functional consequences relating to stress induced cardiovascular reserve, perfusion and vasoregulation. In addition this review will introduce a variety of techniques aiming to expand the envelope of conventional measurements.

Alterations in transmural myocardial strain: an early marker of left ventricular dysfunction in mitral regurgitation?

BACKGROUND

In asymptomatic patients with severe isolated mitral regurgitation (MR), identifying the onset of early left ventricular (LV) dysfunction can guide the timing of surgical intervention. We hypothesized that changes in LV transmural myocardial strain represent an early marker of LV dysfunction in an ovine chronic MR model.

METHODS AND RESULTS

Sheep were randomized to control (CTRL, n=8) or experimental (EXP, n=12) groups. In EXP, a 3.5- or 4.8-mm hole was created in the posterior mitral leaflet to generate "pure" MR. Transmural beadsets were inserted into the lateral and anterior LV wall to radiographically measure 3-dimensional transmural strains during systole and diastolic filling, at 1 and 12 weeks postoperatively. MR grade was higher in EXP than CTRL at 1 and 12 weeks (3.0 [2-4] versus 0.5 [0-2]; 3.0 [1-4] versus 0.5 [0-1], respectively, both P<0.001). At 12 weeks, LV mass index was greater in EXP than CTRL (201+/-18 versus 173+/-17 g/m(2); P<0.01). LVEDVI increased in EXP from 1 to 12 weeks (P=0.015). Between the 1 and 12 week values, the change in BNP (-4.5+/-4.4 versus -3.0+/-3.6 pmol/L), PRSW (9+/-13 versus 23+/-18 mm Hg), tau (-3+/-11 versus -4+/-7 ms), and systolic strains was similar between EXP and CTRL. The changes in longitudinal diastolic filling strains between 1 and 12 weeks, however, were greater in EXP versus CTRL in the subendocardium (lateral: -0.08+/-0.05 versus 0.02+/-0.14; anterior: -0.10+/-0.05 versus -0.02+/-0.07, both P<0.01).

CONCLUSIONS

Twelve weeks of ovine "pure" MR caused LV remodeling with early changes in LV function detected by alterations in transmural myocardial strain, but not by changes in BNP, PRSW, or tau.

The role of left ventricular long axis contraction in patients with asymptomatic non-ischemic mitral valve regurgitation and normal systolic function

BACKGROUND

Several indices have been proposed in order to better evaluate chronic mitral regurgitation, however, none of them is unique, thus underlying the diagnostic deficiency. We aimed to investigate the role of long axis contraction in both ventricles in patients with non-ischemic asymptomatic mitral regurgitation (MR).

METHODS

Eighty-nine patients (40 men, mean age 59.9+/-13.5 years) with non-ischemic asymptomatic MR along with 50 healthy controls were studied. An echocardiographic, including tissue Doppler imaging study, an exercise radionuclide cineangiography and a cardiac catheterization were also performed.

RESULTS

Fifty of 89 patients (56.2%) had a normal response of left ventricular (LV) ejection fraction on exercise. LV end-diastolic diameter and volume index were significantly higher in patients with an impaired LV response. Moreover, systolic wave maximal velocity and systolic wave slope both at the lateral wall and at the inter-ventricular septum were significantly lower in patients with an impaired LV response. Systolic wave maximal velocity at the lateral wall was the index that best predicted LV response to exercise; while a cutoff value of 9.5 cm/s predicted an impaired LV response with a sensitivity of 96% and a specificity of 100%. MR as defined by the width of vena contracta, was mild/moderate in 78% of patients with a systolic wave maximal velocity at the lateral wall >9.5 cm/s and severe in 69.2% of patients with a velocity <9.5 cm/s.

CONCLUSION

In patients with asymptomatic non-ischemic MR, the evaluation of LV long axis contraction at rest can unmask a subnormal LV functional status.