Left ventricular diastolic function in mitral stenosis.

The assessment of left ventricular (LV) function in the setting of mitral stenosis (MS) has been critically examined for decades. Accurate assessment of aberrations in diastolic function is important as these subjects often present with signs and symptoms of heart failure and pulmonary congestion that cannot be solely explained by the severity of mechanical obstruction. Echocardiographic evaluation of diastolic dysfunction includes an evaluation of reduced LV compliance, diminished restoring forces, and enhanced stiffness, which are challenging in the setting of MS owing to altered hemodynamic loading. Conventional echocardiographic and Doppler measures offer limited information. Novel assessments employing speckle tracking echocardiography are relatively less studied. A more comprehensive assessment including clinical evaluation, identification of concomitant disorders, and comorbidities is particularly warranted in older subjects with degenerative MS to suspect diastolic dysfunction and arrive at optimal medical therapy or intervention. This review provides an overview of etiological, pathophysiological, echocardiographic, and invasive assessment of diastolic dysfunction in the setting of MS, with specific focus on strengths and limitations of available echocardiographic and Doppler techniques.

Incremental prognostic value of multichamber deformation imaging and renal function status to predict adverse outcome in heart failure with reduced ejection fraction.

AIMS: Deformation imaging, particularly of left-sided heart, is fast becoming an essential tool in clinical cardiology. However, data are scant regarding the value of biventricular and bi-atrial deformation in association with comorbidities in heart failure with reduced left ventricular ejection fraction (HFREF). METHODS AND RESULTS: Forty-nine subjects (72 ± 13 years; 28 male) with HFREF and 14 age-matched controls underwent deformation imaging including LV global longitudinal strain (LVGLS%), right ventricular strain (RVS%), and left atrial reservoir strain (LARS%). Standard echo parameters included LVEF%, E/E' ratio, and pulmonary artery systolic pressure (PASP). Mean ± SD of LVEF, LVGLS%, and RVS% were 31% ± 8%, 7% ± 3%, and 17% ± 7%, respectively, and were significantly lower compared with controls (all P < .0001). Over a follow-up period of 4.2 years, 24% of patients died and 48% had a composite outcome of death and heart failure hospitalization. In the logistic regression model, taking the composite of death and heart failure hospitalization as a dichotomous variable, RVS%, E/E' ratio, and PASP were the only significant univariate predictors of adverse outcome (R2  = .68, all P < .05). In the multivariate model, however, only PASP predicted adverse outcome. PASP also had the largest AUC (0.8) in the ROC analysis. A creatinine level of >88 µmol/L (SCREAT) and a cutoff value of LA reservoir strain (LARS %) at <16.7% provided the best sensitivity (86%) and specificity (40%) with an odds ratio of 3.8. In the Kaplan-Meier survival estimate, LARS%-SCREAT predicted all-cause mortality and HF hospitalization. CONCLUSION: Multichamber deformation imaging along with renal function and PASP could best predict adverse outcome in HFREF.

Arterial-ventricular and interventricular interaction in isolated post-capillary and combined pulmonary hypertension in severe mitral stenosis.

BACKGROUND: Isolated post-capillary pulmonary hypertension (Ipc-PH) is characterized by elevated left atrial pressures that are passively transmitted upstream, whereas combined pre- and post-capillary PH (Cpc-PH) demonstrates additional reactive changes in pulmonary vasculature. The increased load imposed on the right ventricle (RV) influences left ventricular (LV) mechanics by means of interventricular interaction. However, there is lack of evidence to substantiate the effect of possible additional alterations in the arterio-ventricular (AV) coupling and their effect on LV function. Considering the discrepant RV load in Cpc-PH and Ipc-PH, we sought to investigate whether these two conditions are also characterized by differential alterations in AV coupling. METHODS AND RESULTS: Invasive hemodynamic and echocardiographic data of 120 patients with PH due to severe rheumatic mitral stenosis before and immediately after percutaneous valvulotomy, along with 40 age-matched healthy controls, were analyzed. Effective arterial (E a) and ventricular elastance (E es) were measured. PH patients demonstrated elevated LV afterload (E a) along with AV uncoupling, and these derangements were more evident in the Cpc-PH group [E a: 3.3 (2.3-5.4) vs 2.6 (2.1-3.5) mmHg/mL, E a/E es: 0.73 (0.6-0.9) vs 0.88 (0.7-1.2), p < 0.05]. In addition, PH was associated with reduced LV deformation, which was mainly determined by elevated E a, while the effect of interventricular interaction was limited to the septal wall. CONCLUSIONS: Our results suggest that in addition to the interventricular interaction, an abnormal AV coupling contributes to the altered LV mechanics that has been associated with adverse prognosis in Cpc-PH.

The impact of arterial load on left ventricular performance: an invasive haemodynamic study in severe mitral stenosis.

KEY POINTS: A hallmark of mitral stenosis (MS) is the markedly altered left ventricular (LV) loading. As most of the methods used to determine LV performance in MS patients are influenced by loading conditions, previous studies have shown conflicting results. The present study calculated LV elastance, which is a robust method to quantify LV function. We demonstrate that LV loading in MS patients is elevated but normalizes after valve repair and might be a result of reflex pathways. Additionally, we show that the LV in MS is less compliant than normal due to a combination of right ventricular loading and the valvular disease itself. Immediately after valve dilatation the increase in blood inflow into the LV results in even greater LV stiffness. Our findings enrich our understanding of heart function in MS patients and provide a simple reproducible way of assessing LV performance in MS. ABSTRACT: Left ventricular (LV) function in rheumatic mitral stenosis (MS) remains an issue of controversy, due to load dependency of previously employed assessment methods. We investigated LV performance in MS employing relatively load-independent indices robust to the altered loading state. We studied 106 subjects (32 ± 8 years, 72% female) with severe MS (0.8 ± 0.2 cm(2) ) and 40 age-matched controls. MS subjects underwent simultaneous bi-ventricular catheterization and transthoracic echocardiography (TTE) before and immediately after percutaneous transvenous mitral commisurotomy (PTMC). Sphygmomanometric brachial artery pressures and TTE recordings were simultaneously acquired in controls. Single-beat LV elastance (Ees ) was employed for LV contractility measurements. Effective arterial elastance (Ea ) and LV diastolic stiffness were measured. MS patients demonstrated significantly elevated afterload (Ea : 3.0 ± 1.3 vs. 1.5 ± 0.3 mmHg ml(-1) ; P < 0.001) and LV contractility (Ees : 4.1 ± 1.6 vs. 2.4 ± 0.5 mmHg ml(-1) ; P < 0.001) as compared to controls, with higher Ea in subjects with smaller mitral valve area (≤ 0.8 cm(2) ) and pronounced subvalvular fusion. Stroke volume (49 ± 16 to 57 ± 17 ml; P < 0.001) and indexed LV end-diastolic volume (LVEDVindex : 57 ± 16 to 64 ± 16 ml m(-2) ; P < 0.001) increased following PTMC while Ees and Ea returned to more normal levels. Elevated LV stiffness was demonstrated at baseline and increased further following PTMC. Our findings provide evidence of elevated LV contractility, increased arterial load and increased diastolic stiffness in severe MS. Following PTMC, both LV contractility and afterload tend to normalize.

Transcatheter para mitral annular ring leak device closure - A case report.

Para mitral annular ring leakage can occur following ring dehiscence after mitral annuloplasty. Percutaneous device closure of para-annular ring leakage can be performed successfully to treat such regurgitations with good transesophageal echocardiography guidance and patient selection. While para valvular device closure has been described in the medical literature, there have been few anecdotal reports published on para ring leak device closures. In this case, we highlight our experience from the successful closure of a para mitral annular ring closure with an AVP III device. The patient had a para annular ring regurgitation post coronary artery bypass grafting with mitral ring annuloplasty presenting with hemolytic anemia and acute renal failure, successfully treated by percutaneous device closure. Learning objective: This report describes the safety and effectiveness of a transcatheter para ring leak closure with an AVP III device. We applied the principles of device closure of paravalvular leak from our experience and related data from literature for this case and describe various hardware and techniques used for a successful closure of a para mitral ring leak.

Value of two-dimensional speckle tracking and real time three-dimensional echocardiography for the identification of subclinical left ventricular dysfunction in patients referred for routine echocardiography.

BACKGROUND: While speckle tracking echocardiography (2DSTE) can be used to study longitudinal, circumferential, and radial function, real time 3D echocardiography (3DE) generates dynamic time-volume curves, offering a wide array of new parameters for characterizing mechanical and volumetric properties of the left ventricle (LV). Our aim was to investigate the merit of these new techniques to separate normal from abnormal echocardiograms as well as to identify subclinical disease in reportedly normal subjects. METHODS: Eighty-one patients (mean age 61 ± 16 years) underwent standard 2D echocardiography (2DE) enhanced by 2DSTE and 3DE. The data included LV volumes and ejection fraction (EF), velocities, strain/strain rate, and peak ejection/filling rates. The patients were divided into Group 1: normal (n = 42) and Group 2: abnormal (n = 39) on the basis of an expert interpretation of the resting 2DE. RESULTS: Global longitudinal strain (%) was 17 ± 4 in Group1 and 14 ± 4 in Group2 (P < 0.002). Strain rates (SR, 1/sec) at peak systole (1.1 ± 0.2 vs 0.9 ± 0.3, P < 0.001) and early diastole (1.3 ± 0.3 vs 0.9 ± 0.3, P < 0.001) were also higher in Group1. Three-dimensional peak ejection and filling rates (EDV/sec) were significantly higher in Group1 (-2.5 ± 0.4 vs -2.1 ± 0.7, and 1.8 ± 0.2 vs 1.5 ± 0.5, P < 0.002, P < 0.001, respectively). The best discriminatory power for predicting a normal 2DE was systolic SR with a sensitivity of 82% and a specificity of 54% using a cutoff value of 1.09. Interestingly, 19/41 (46%) of Group1 patients had systolic SR < 1.09, suggesting subclinical disease. CONCLUSIONS: 2DSTE and 3DE can discriminate between normal and abnormal echocardiograms and have the potential to detect subclinical LV dysfunction.

Transcatheter Aortic Valve Implantation in the Descending Aorta: History Revisited!

An elderly patient with significant aortic regurgitation presented with heart failure. Dilation of the aortic root precluded a transcatheter anatomic site valve implantation, and prohibitive operative risk ruled against surgical implantation. A bail-out transcatheter implantation of the aortic valve in the descending aorta was successfully carried out with satisfactory outcomes.

Principles and clinical applications of strain imaging.

M-Mode echocardiography, 2-D grey scale imaging and standard Doppler that constitute conventional echocardiography has been used for over many decades now. Although these modalities form the backbone in routine clinical echocardiography, its inability to objectively quantify left ventricular function at regional and global levels as well as its loading and heart rate dependency make conventional echocardiography an incomplete tool in clinical situations. Tissue Doppler imaging (which includes myocardial velocity, displacement and strain) has been successfully used in a variety of clinical situations, from investigations of diastolic function to implantation of bi-ventricular pacing for cardiac resynchronization therapy and even in preclinical diagnosis of genetic diseases such as hypertrophic cardiomyopathy. Strain imaging has been found to be superior to velocity in a variety of clinical conditions and enables us to quantify deformation as a measurable number in terms of regional myocardial deformation. Strain and strain rate have to be assessed together since they provide complementary information somewhat analogous to ejection fraction and contraction. This article has tried to simplify its principles, understand its limitations and know its utility to ensure having a better knowledge of this promising tool before one starts to actively use it. In this review, focus has been made on the physical, technical and also clinical aspects of strain imaging. In the new world of multi-modality imaging, cardiac magnetic resonance imaging (CMR) and nuclear perfusion scintigraphy (NPS) are the competitors of echocardiography, but it would be of interest to note that even these modalities are also adapting concepts of strain imaging (in CMR) and left ventricular synchronicity (in NPS). This only emphasizes the role of advanced echocardiography as a more economical and stand-alone modality visa vis the other two related technologies. The sooner we adapt to these advanced applications, stronger would be the ground to resolve technical and clinical issues. Strain imaging in its present form cannot win the game alone in this era of multi-modality imaging, but it is almost certain that with continued advancement, tissue Doppler and speckle tracking echocardiography based strain could play a pivotal role in a variety of clinical situations providing much needed incremental information.

Study of left ventricular rotation and torsion in the acute phase of ST-elevation myocardial infarction by speckle tracking echocardiography.

BACKGROUND: The mechanics of the complex left ventricular (LV) myocardial fiber architecture may accurately be assessed by speckle tracking echocardiography (STE). The role of STE to assess LV mechanical dysfunction in the setting of ST segment elevation myocardial infarction (AMI) is still poorly studied. PATIENTS AND METHODS: 29 consecutive patients (55 +/- 13 years) presenting with AMI underwent STE within 72 hours of admission. Reperfusion was achieved with thrombolysis in 15 patients and with primary percutaneous coronary intervention in 14. LV rotational and torsion data were registered during peak systole. Standard Doppler data included LV ejection fraction (EF), mitral inflow deceleration time (DT), and conventional E/A ratio. E/E' ratio (mitral inflow E velocity/tissue Doppler E velocity) was calculated as a marker of LV filling pressure. Twelve subjects with clinically indicated but negative dobutamine stress echocardiogram served as Controls. RESULTS: Peak systolic torsion was not only significantly lower in AMI compared with Controls (13.3 +/- 7.6 vs. 21.8 +/- 6.1; P < 0.01), it was also lower in subjects with LVEF <40% (5.0 +/- 2.9) compared with those who had LVEF >40% (10.6 +/- 6.6; P < 0.02). Torsion had a modest but significantly positive linear relation (R = 0.6; P < 0.05) with DT, not with E/E' or LVEF. CONCLUSION: LV systolic torsion is decreased in AMI and more markedly decreased in patients with LVEF <40%. The most significant linear relationship between DT and torsion may possibly indicate that the LV mechanical dysfunction is also associated with altered filling dynamics.

Quantification of low-dose dobutamine stress using speckle tracking echocardiography in coronary artery disease.

AIMS: We sought to evaluate the utility of speckle tracking echocardiography (STE) for detecting left ventricular (LV) mechanical abnormalities during low-dose (20 microg) dobutamine stress (DSE). METHODS AND RESULTS: Twenty-nine patients (56 +/- 12 years) with a history of recent acute coronary events (ACE) underwent STE-DSE. Left ventricular images, sampled at frame rates 70-100 Hz, were analysed off-line (Echopac BT 6.0.0). Velocity, strain, and rotational imaging were performed. Twenty patients had LV ejection fraction (EF) >40% (Group 1) whereas nine patients had LVEF <40% (Group 2). Average heart and frame rates were identical during DSE in the two groups (P = ns). Global circumferential strain (%) was significantly lower in Group 2 compared with Group 1 (10.65 +/- 5.30 vs. 16.82 +/- 6.61; P < 0.05) at rest and during peak stress (14.72 +/- 6.51 vs. 21.13 +/- 7.2; P < 0.05). The global peak rotation rate (degree/s) was, however, higher at rest in Group 2 (70 +/- 97 vs. 19 +/- 67; P < 0.05) and 20 microg stress. Peak systolic velocity increased in three of the four LV walls at 20 microg (in Groups 1 and 2). A global rotational rate increased significantly at 20 microg during systole in both the groups, but was unchanged in Group 2 during diastole. CONCLUSIONS: Speckle tracking echocardiography dobutamine stress appears to provide comprehensive information on LV mechanical status in the aftermath of ACE. The modality may help risk stratify such patients.

Cardiac incoordination induced by left bundle branch block: its relation with left ventricular systolic function in patients with and without cardiomyopathy.

BACKGROUND: Although left bundle branch block (LBBB) alters the electrical activation of the heart, it is unknown how it might change the process of myocardial coordination (MC) and how it may affect the left ventricular (LV) systolic function. The present study assessed the effects of LBBB on MC in patients with LBBB with and without dilated (DCMP) or ischemic cardiomyopathy (ICMP). METHODS: Tissue Doppler echocardiography (TDE) was performed in 86 individuals: 21 with isolated LBBB, 26 patients with DCMP + LBBB, 19 patients with ICMP + LBBB and in 20 healthy individuals (Controls). MC was assessed analyzing the myocardial velocity profiles obtained from six basal segments of the LV using TDE. The LV systolic function was assessed by standard two-dimensional echocardiography and by TDE. RESULTS: Severe alterations in MC were observed in subjects with LBBB as compared with controls (P < 0.01 for all comparisons); these derangements were even worse in patients with DCMP and ICMP (P < 0.001 for comparisons with Controls and P < 0.01 for comparison with individuals with isolated LBBB). Some parameters of MC differed significantly between DCMP and ICMP (P < 0.01). A good or very good correlation coefficient was found between variables of MC and variables of LV systolic function. CONCLUSION: LBBB induces severe derangement in the process of MC that are more pronounced in patients with cardiomyopathies and that significantly correlates with the LV systolic function. The assessment of MC may help in the evaluation of the etiology of dilated cardiomyopathy.

Impaired myocardial functional reserve in hypertension and diabetes mellitus without coronary artery disease: Searching for the possible link with congestive heart failure in the myocardial Doppler in diabetes (MYDID) study II.

BACKGROUND: Although the impact of type 2 diabetes mellitus (DM) and hypertension (HTN) on myocardial function has recently been studied using tissue Doppler echocardiography (TDE), the independent role of both conditions, and the influence of other risk factors on myocardial function has not been completely defined, particularly in absence of coronary artery disease (CAD). The aim of this study was to assess the myocardial functional reserve in patients with DM or HTN with apparently normal left ventricular (LV) systolic function. METHODS: Standard and dobutamine stress echocardiography using TDE was performed in 128 subjects: 59 had DM, 20 had HTN, 27 had both DM and HTN (HTN + DM), and 22 subjects were controls (C). Subjects with known CAD and depressed LV function were excluded. In addition, standard two-dimensional and Doppler measurements, LV regional peak systolic (PSV), early (E') and late (A') diastolic velocities, strain (S%) and strain rate (SR), were assessed at rest and peak stress. RESULTS: The LV mass did not differ, although relative wall thickness was significantly higher in subjects with HTN + DM and HTN. The PSV did not differ at rest but was lowest in subjects with HTN + DM at peak stress. The E' wave velocity was significantly lower in subjects with HTN + DM both at rest and during peak stress, as were S% and SR. CONCLUSIONS: The addition of DM to HTN has a negative effect on LV systolic and diastolic functions. A depressed myocardial functional reserve might be postulated as one of the pathophysiologic mechanisms for the excessive occurrence of congestive heart failure in patients with DM or HTN.

Differing myocardial response to a single session of hemodialysis in end-stage renal disease with and without type 2 diabetes mellitus and coronary artery disease.

BACKGROUND: Though hemodialysis (HD) acutely improves cardiac function, the impact of background diseases like coronary artery disease (CAD) and Type 2 diabetes (DM) in the setting of end-stage renal disease (ESRD) is not known. Tissue velocity echocardiography (TVE) offers a fast choice to follow changes in myocardial function after HD in ESRD with concomitant DM and /or CAD. METHODS: 46 subjects (17 with ESRD, Group 1; 15 with DM, Group 2; 14 with DM+CAD, Group 3) underwent standard and TVE prior to and shortly after HD. Besides standard Doppler variables, regional myocardial systolic and diastolic velocities, as well as systolic strain rate were post processed. RESULTS: Compared with pre-HD, post-HD body weight (kg) significantly decreased in all the three groups (51 +/- 9 vs. 48 +/- 8, 62 +/- 10 vs.59 +/- 10, and 61 +/- 9 vs. 58 +/- 9 respectively; all p < 0.01). Left ventricular end diastolic dimensions (mm) also decreased post- HD (46 +/- 5 vs. 42 +/- 7, 53 +/- 7 vs. 50 +/- 7, 51 +/- 7 vs. 47 +/- 8 respectively; all p < 0.01). Regional longitudinal peak systolic velocity in septum (cm/s) significantly increased post-HD in Group 1(5.7 +/- 1.6 vs. 7.2 +/- 2.3; p < 0.001) while remained unchanged in the other two groups. Similar trends were noted in other left ventricular walls. When the myocardial velocities (cm/s) were computed globally, the improvement was seen only in Group 1 (6.3 +/- 1.5 vs. 7.9 +/- 2.0; p < 0.001). Global early regional diastolic velocity (cm/s) improved in Group 1, remained unchanged in Group 2, while significantly decreased in Group 3(-5.9 +/- 1.3 vs. -4.1 +/- 1.8; p < 0.01). Global systolic strain rate (1/sec) increased in the first 2 Groups but remained unchanged (-0.87 +/- 0.4 vs. -0.94 +/- 0.3; p = ns) in Group 3. CONCLUSION: A single HD session improves LV function only in ESRD without coexistent DM and/or CAD. The present data suggest that not only dialysis-dependent changes in loading conditions but also co-existent background diseases determine the myocardial response to HD.

Acute administration of a single dose of valsartan improves left ventricular functions: a pilot study to assess the role of tissue velocity echocardiography in patients with systemic arterial hypertension in the TVE-valsartan study I.

BACKGROUND: The advent of colour-coded tissue velocity echocardiography (TVE) has now made it possible to quantify left ventricular (LV) functions in patients with systemic arterial hypertension (HTN). Hypothesis In this project, we have studied the cardiac effects of a single dose of orally administered valsartan in patients with known HTN. METHODS: Fifty-five patients with HTN with a mean age of 56 +/- 10 years were given an early morning dose of 80 mg valsartan withholding regular antihypertensive medications on the day of investigation. TVE images, acquired on VIVID systems were digitized for postprocessing of longitudinal and radial peak systolic velocities, strain rate, and systolic and diastolic time intervals before (pre) and 5 h after (post) administration of the drug. RESULTS: Blood pressure (mmHg) pre and post, respectively, were 147 +/- 15 versus 137 +/- 14 systolic and 90 +/- 7 versus 86 +/- 7 diastolic (all P<0.01). LV longitudinal systolic velocities (cm s(-1)) were significantly higher post in LV septum (5.7 +/- 1.1 versus 6.4 +/- 1.6; P<0.001) with similar results obtained in other LV walls. Radial strain rate (1 s(-1)) was significantly higher post compared with pre valsartan (2.1 +/- 0.6 versus 2.3 +/- 0.9; P<0.01). Regional diastolic filling and ejection times (ms) were significantly shorter post (390 +/- 122 versus 370 +/- 120 and 275 +/- 32 versus 163 +/- 36 respectively; all P<0.05). CONCLUSIONS: Within 5 h after oral administration of valsartan, improvement in regional myocardial systolic functions could be registered. Although the changes could well be secondary to afterload reduction, additional effects of the drug, evidenced by improved strain rate that is relatively load-independent, may have contributed in this improvement.

Assessment of atrial regional and global electromechanical function by tissue velocity echocardiography: a feasibility study on healthy individuals.

BACKGROUND: The appropriate evaluation of atrial electrical function is only possible by means of invasive electrophysiology techniques, which are expensive and therefore not suitable for widespread use. Mechanical atrial function is mainly determined from atrial volumes and volume-derived indices that are load-dependent, time-consuming and difficult to reproduce because they are observer-dependent. AIMS: To assess the feasibility of tissue velocity echocardiography (TVE) to evaluate atrial electromechanical function in young, healthy volunteers. SUBJECTS AND METHODS: We studied 37 healthy individuals: 28 men and nine women with a mean age of 29 years (range 20-47). Standard two-dimensional (2-D) and Doppler echocardiograms with superimposed TVE images were performed. Standard echocardiographic images were digitized during three consecutive cardiac cycles in cine-loop format for off-line analysis. Several indices of regional atrial electrical and mechanical function were derived from both 2-D and TVE modalities. RESULTS: Some TVE-derived variables indirectly reflected the atrial electrical activation that follows the known activation process as revealed by invasive electrophysiology. Regionally, the atrium shows an upward movement of its walls at the region near the atrio-ventricular ring with a reduction of this movement towards the upper levels of the atrial walls. The atrial mechanical function as assessed by several TVE-derived indices was quite similar in all left atrium (LA) walls. However, all such indices were higher in the right (RA) than the LA. There were no correlations between the 2-D- and TVE-derived variables expressing atrial mechanical function. Values of measurement error and repeatability were good for atrial mechanical function, but only acceptable for atrial electrical function. CONCLUSION: TVE may provide a simple, easy to obtain, reproducible, repeatable and potentially clinically useful tool for quantifying atrial electromechanical function.

Automated intraventricular septum segmentation using non-local spatio-temporal priors.

Automated robust segmentation of intra-ventricular septum (IVS) from B-mode echocardiographic images is an enabler for early quantification of cardiac disease. Segmentation of septum from ultrasound images is very challenging due to variations in intensity/contrast in and around the septum, speckle noise and non-rigid shape variations of the septum boundary. In this work, we effectively address these challenges using an approach that merges novel computer vision ideas with physiological markers present in cardiac scans. Specifically, we contribute towards the following: (1) A novel 1-D active contour segmentation approach that utilizes non-local (NL) temporal cues, (2) Robust initialization of the active contour framework, based on NL-means de-noising, and MRF based clustering that incorporates physiological cues. We validate our claims using cardiac measurement results on approximately 30 cardiac scan videos (approximately 2000 ultrasound frames in total). Our method is fully automatic and near real time (0.1 sec/frame) implementation.

Quality metric for Parasternal Long AXis B-mode echocardiograms.

This paper presents a method for automatically estimating the quality of Parasternal Long AXis (PLAX) B-mode echocardiograms. The purpose of the algorithm is to provide live feedback to the user on the quality of the acquired image. The proposed approach uses Generalized Hough Transform to compare the structures derived from the incoming image to a representative atlas, thereby providing a quality metric (PQM). On 133 PLAX images from 35 patients, we show: 1) PQM has high correlation with manual ratings from an expert echocardiographer 2) PQM has high correlation with contrast-to-noise ratio, a traditional indicator of image quality 3) on images with high PQM, error in automatic septal wall thickness measurement is low, and vice versa.

Global left atrial strain correlates with CHADS2 risk score in patients with atrial fibrillation.

BACKGROUND: The aim of this cross-sectional study was to explore the association between echocardiographic parameters and CHADS2 score in patients with nonvalvular atrial fibrillation (AF). METHODS: Seventy-seven subjects (36 patients with AF, 41 control subjects) underwent standard two-dimensional, Doppler, and speckle-tracking echocardiography to compute regional and global left atrial (LA) strain. RESULTS: Global longitudinal LA strain was reduced in patients with AF compared with controls (P < .001) and was a predictor of high risk for thromboembolism (CHADS2 score ≥ 2; odds ratio, 0.86; P = .02). LA strain indexes showed good interobserver and intraobserver variability. In sequential Cox models, the prediction of hospitalization and/or death was improved by addition of global LA strain and indexed LA volume to CHADS2 score (P = .003). CONCLUSIONS: LA strain is a reproducible marker of dynamic LA function and a predictor of stroke risk and cardiovascular outcomes in patients with AF.

Role of N-terminal pro-brain natriuretic peptide in ST-segment elevation myocardial infarction: experience from a tertiary centre in India.

BACKGROUND: Role of biomarkers in ST-segment elevation myocardial infarction (STEMI) is paramount, as they aid in diagnosis and gauge prognosis of the disease. In this project, we sought to study the short-term outcome and clinical associates of N-terminal pro-brain natriuretic peptide (NT-proBNP) in the setting of STEMI at a tertiary center in India. METHODS: In all, 173 STEMI patients (mean age: 57 ± 12 years, 38 women) had their NT-proBNP assayed in addition to troponins and high-sensitive C-reactive protein. Subjects were divided according to NT-proBNP levels into 2 groups: group 1 (NT-proBNP ≤100 pg/mL) and group 2 (NT-proBNP >100 pg/mL). RESULTS: NT-proBNP values (pg/mL) were elevated in group 2 (group 1: 61.7 ± 6.2; group 2: 1006.5 ± 990.6, P < 0.0001). Significantly greater number of females had elevated NT-proBNP (P < 0.05) that could be predicted by the duration of chest pain related to STEMI (area under the curve: 0.72), and age at presentation (area under the curve: 0.66). Multiple regression analysis showed a strong inverse association between NT-proBNP and left ventricular ejection fraction and a strong positive association between the peptide and high-sensitive C-reactive protein. A significant positive association was also noted between NT-proBNP and troponin I (all P < 0.05, Global R = 0.47). Diabetes mellitus and/or hypertension, and infarction localization showed no effect on NT-proBNP levels along with death, primary coronary intervention-related bleeding, and arrhythmias, (χ, P = ns). CONCLUSIONS: The data suggest that women are more likely to have increased NT-proBNP while presenting with STEMI. Duration of chest pain and age at presentation are the best predictors of elevated NT-proBNP, though without much bearing on short-term morbidity and mortality.