Myocardial calcification is associated with endocardial ablation failure of post-myocardial infarction ventricular tachycardia.

AIMS: In patients with post-myocardial infarction (post-MI) ventricular tachycardia (VT), the presence of myocardial calcification (MC) may prevent heating of a subepicardial VT substrate contributing to endocardial ablation failure. The aims of this study were to assess the prevalence of MC in patients with post-MI VT and evaluate the impact of MC on outcome after endocardial ablation. METHODS AND RESULTS: In 158 patients, the presence of MC was retrospectively assessed on fluoroscopy recordings in seven standard projections obtained during pre-procedural coronary angiograms. Myocardial calcification, defined as a distinct radiopaque area that moved synchronously with the cardiac contraction, was detected in 30 patients (19%). After endocardial ablation, only 6 patients (20%) with MC were rendered non-inducible compared with 56 (44%) without MC (P = 0.033) and of importance, 8 (27%) remained inducible for the clinical VT [compared with 9 (6%) patients without MC; P = 0.003] requiring therapy escalation. After a median follow-up of 31 months, 61 patients (39%) had VT recurrence and 47 (30%) died. Patients with MC had a lower survival free from the composite endpoint of VT recurrence or therapy escalation at 24-month follow-up (26% vs. 59%; P = 0.003). Presence of MC (HR 1.69; P = 0.046), a lower LV ejection fraction (HR 1.03 per 1% decrease; P = 0.017), and non-complete procedural success (HR 2.42; P = 0.002) were independently associated with a higher incidence of VT recurrence or therapy escalation. CONCLUSION: Myocardial calcification was present in 19% of post-MI patients referred for VT ablation and was associated with a high incidence of endocardial ablation failure.

Comparing the Non-Quiver and Quiver Techniques for Identification of the Endocardial Borders Used for Speckle-Tracking Analysis of the Ventricles of the Fetal Heart.

This study compared the non-quiver with the quiver technique for identifying the end-systolic and end-diastolic endocardium of the fetal right ventricle (RV) and left ventricle (LV) used for speckle-tracking analysis. Bland-Altman and t test analyses showed no significant differences in measurements between the techniques for the RV and LV. The difference in the time required to perform the non-quiver analysis was significantly longer (P < .001) for the RV and LV than the quiver technique. The quiver technique allows the examiner to efficiently identify the endocardial borders of the fetal heart compared with the non-quiver method.

Effect of Temporal and Spatial Smoothing on Speckle-Tracking-Derived Strain in Neonates.

Clinical application of strain in neonates requires an understanding of which image acquisition and processing parameters affect strain values. Previous studies have examined frame rate, transmitting frequency, and vendor heterogeneity. However, there is a lack of human studies on how user-regulated spatial and temporal smoothing affect strain values in 36 neonates. This study examined nine different combinations of spatial and temporal smoothing on peak systolic left ventricular longitudinal strain in 36 healthy neonates. Strain values were acquired from four-chamber echocardiographic images in the software-defined epicardial, midwall, and endocardial layers in the six standard segments and average four-chamber stain. Strain values were compared using repeated measure ANOVAs. Overall, spatial smoothing had a larger impact than temporal smoothing, and segmental strain values were more sensitive to smoothing settings than average four-chamber strain. Apicoseptal strain decreased by approximately 4% with increasing spatial smoothing, corresponding to a 13-19% proportional change (depending on wall layer). Therefore, we recommend clinicians be mindful of smoothing settings when assessing segmental strain values.

Tracking the motion of intracardiac structures aids the development of future leadless pacing systems.

BACKGROUND: Leadless pacemakers preclude the need for permanent leads to pace endocardium. However, it is yet to be determined whether a leadless pacemaker of a similar design to those manufactured for the right ventricle (RV) fits within the left ventricle (LV), without interfering with intracardiac structures. METHODS: Cardiac computed tomography scans were obtained from 30 patients indicated for cardiac resynchronisation therapy upgrade. The mitral valve annulus, chordae tendineae, papillary muscles and LV endocardial wall were marked in the end-diastolic frame. Intracardiac structures motions were tracked through the cardiac cycle. Two pacemaker designs similar to commercially manufactured leadless systems (Abbott's Nanostim LCP and Medtronic's Micra TPS) as well as theoretical designs with calculated optimal dimensions were evaluated. Pacemakers were virtually placed across the LV endocardial surface and collisions between them and intracardiac structures were detected throughout the cycle. RESULTS: Probability maps of LV intracardiac structures collisions on a 16-segment AHA model indicated possible placement for the Nanostim LCP, Micra TPS, and theoretical designs. Thresholding these maps at a 20% chance of collision revealed only about 36% of the endocardial surface remained collision-free with the deployment of Micra TPS design. The same threshold left no collision-free surface in the case of the Nanostim LCP. To reach at least half of the LV endocardium, the volume of Micra TPS, which is the smaller design, needed to be decreased by 41%. CONCLUSION: Due to the presence of intracardiac structures, placement of leadless pacemakers with dimensions similar to commercially manufactured RV systems would be limited to apical regions.

Radiofrequency ablation lesion assessment using optical coherence tomography - a proof-of-concept study.

BACKGROUND: Radiofrequency catheter ablation (RFA) is an effective treatment for atrial fibrillation. However, ablation lesions are usually only assessed functionally. The immediate effect of RFA on the tissue is not directly visualized. Optical coherence tomography (OCT) is an imaging technique that uses light to capture high-resolution images with histology-like quality. Therefore, it might be used for high-precision imaging of ablation lesions. METHODS AND RESULTS: Radiofrequency ablation lesions (n = 25) were produced on the freshly excised left and right ventricular porcine endocardium. A Thermocool ST SF NAV ablation catheter (Biosense Webster Inc) and an EP-Shuttle ablation generator (Stockert GmbH) were used to produce ablation lesions with powers from 10 to 40 W (energies ranging from 100 Ws to 900 Ws). After ablation, the tissue was imaged with a swept source OCT system (at a wavelength of 1300 nm). Subsequently, the ablation lesions underwent the histological analysis. The ablation lesions could be visualized by OCT in all 17 samples with ablation powers ≥20 W, meanwhile, no lesion could be observed in the other eight samples with lower power (10 W). Lesion depths and lesion radiuses, as assessed by OCT, correlated well with those observed on the subsequent histological analysis (Spearman's r = 0.94, P < 0.001 and r = 0.84, P < 0.001). In addition, successful three-dimensional reconstructions of ablation lesions were performed. CONCLUSION: OCT can provide a visual high-resolution assessment of ablation lesions.

Imaging of subendocardial adipose tissue and fiber orientation distributions in the human left atrium using optical coherence tomography.

BACKGROUND: Optical coherence tomography (OCT) has the potential to provide real-time imaging guidance for atrial fibrillation ablation, with promising results for lesion monitoring. OCT can also offer high-resolution imaging of tissue composition, but there is insufficient cardiac OCT data to inform the use of OCT to reveal important tissue architecture of the human left atrium. Thus, the objective of this study was to define OCT imaging data throughout the human left atrium, focusing on the distribution of adipose tissue and fiber orientation as seen from the endocardium. METHODS AND RESULTS: Human hearts (n = 7) were acquired for imaging the left atrium with OCT. A spectral-domain OCT system with 1325 nm center wavelength, 6.5 µm axial resolution, 15 µm lateral resolution, and a maximum imaging depth of 2.51 mm in the air was used. Large-scale OCT image maps of human left atrial tissue were developed, with adipose thickness and fiber orientation extracted from the imaging data. OCT imaging showed scattered distributions of adipose tissue around the septal and pulmonary vein regions, up to a depth of about 0.43 mm from the endocardial surface. The total volume of adipose tissue detected by OCT over one left atrium ranged from 1.42 to 28.74 mm3 . Limited fiber orientation information primarily around the pulmonary veins and the septum could be identified. CONCLUSION: OCT imaging could provide adjunctive information on the distribution of subendocardial adipose tissue, particularly around thin areas around the pulmonary veins and septal regions. Variations in OCT-detected tissue composition could potentially assist ablation guidance.

Regional layer-specific longitudinal peak systolic strain using exercise stress two-dimensional speckle-tracking echocardiography for the detection of functionally significant coronary artery disease.

The present study aimed to investigate whether layer-specific regional peak-systolic longitudinal strain (LS) measurement on transthoracic echocardiogram (TTE) with exercise stress can be useful for the detection of functionally significant coronary artery disease as confirmed by invasive fractional flow reserve (FFR) in stable patients. This is a prospective analysis of 88 coronary arteries in 30 stable patients undergoing invasive FFR measurement and ergometer exercise stress TTE. Regional LS in the mid, endocardial and epicardial layers was calculated at rest, peak stress and early and late recovery phases after the exercise stress test. The endocardial-to-epicardial LS ratio was calculated as an indicator of endocardial-layer dependency of the left ventricular myocardium. Ischemic FFR defined as FFR ≤ 0.80 was observed in 33 of 88 coronary arteries. The mid-, endocardial- and epicardial-layer LS at early recovery (- 15.4 ± 5.2 vs. - 13.0 ± 4.4%, P = 0.040; - 15.7 ± 5.1 vs. - 13.2 ± 4.5%, P = 0.029; - 14.6 ± 5.1 vs. - 12.4 ± 4.0%, P = 0.038, respectively) and the percent change in the endocardial-to-epicardial LS ratio from baseline to peak stress, early recovery, and late recovery phases (1.5 ± 11.2% vs. 6.6 ± 10.5%, P = 0.009; 2.8 ± 8.9% vs. 7.1 ± 12.6%, P = 0.002; 5.2 ± 8.8% vs. 8.5 ± 13.7%, P = 0.026; respectively) were significantly more impaired in the ischemic territories (FFR ≤ 0.80) compared with the non-ischemic territories (FFR > 0.80). According to the receiver operating characteristic curve analysis, a combination of endocardial LS and percent change in the endocardial-to-epicardial LS ratio at early recovery phase plus visual evaluation of LV wall motion had incremental diagnostic value for the detection of the ischemic territory compared with visual evaluation alone (area under the curve = 0.752 and 0.618, P = 0.006). The results of this study suggested that assessing layer-specific LS and the endocardial-to-epicardial LS ratio after exercise stress on speckle-tracking TTE may have potential for objective and quantitative evaluation in the assessment of myocardial ischemia. Further studies in a larger population are needed to confirm these findings.

Morphological characterization of vegetation by real-time three-dimensional transesophageal echocardiography in infective endocarditis: Prognostic impact.

PURPOSE: Vegetation size is a prognostic predictor in infective endocarditis (IE) and guides surgical management. The aim of this study was to evaluate the accuracy of real-time 3-dimensional transesophageal echocardiography (RT3DTEE) compared to 2DTEE in the diagnosis and characterization of vegetation, as well as its potential clinical impact. METHODS: Two hundred and three consecutive patients with IE were recruited (2009-2016) and retrospectively analyzed. Vegetation diameters and area from 68 patients were measured by 2DTEE and RT3DTEE at admission. The association between size and systemic embolisms was evaluated with logistic regression models. Differences in the discriminative power for the best dimensions' cutoff points were assessed by comparing the area under the ROC curves (AUC). RESULTS: Vegetation size and area were larger by RT3DTEE (P < 0.001) than by 2DTEE, and RT3DTEE was especially relevant in the characterization of nonfiliform vegetation, Morphology was strongly associated with friability, being sessile vegetation less likely to embolize, compared to filiform and raceme-shaped ones (15.4% vs 46% vs 50%). Major diameter by RT3DTEE had better embolic predictive performance than 2DTEE (AUC 0.76 [0.57-0.89] vs 0.71 [0.53-0.86]; P = 0.611). The best cutoff points associated with embolic events during the infection were 17 mm for RT3DTEE and 15 mm for 2DTEE. Based exclusively on vegetation size, the proportion of patients meeting a surgical indication according to current guidelines is higher using RT3DTEE. CONCLUSIONS: RT3DTEE allows a better characterization of IE vegetation than 2DTEE, what may have a clinical impact on surgical management and also prognostic due to a more accurate prediction of embolic risk.

Endocardial Coronary Artery: A Rare Congenital Coronary Anomaly.

Pediatric chest pain is a common reason for cardiology referral, and evaluation of exertional chest pain requires proper delineation of coronary anatomy. Congenital coronary anomalies are rare and often benign. However, certain anomalies such as intramural coronary arteries and myocardial bridges have been associated with angina, ventricular arrhythmias, and sudden cardiac death. We present a case of a 10-year-old male with exertional chest pain whose coronary anatomy could not be defined by echocardiography and further evaluation by computed tomography angiography revealed a rare congenital coronary anomaly.

Transverse cardiac slicing and optical imaging for analysis of transmural gradients in membrane potential and Ca2+ transients in murine heart.

KEY POINTS: A robust cardiac slicing approach was developed for optical mapping of transmural gradients in transmembrane potential (Vm ) and intracellular Ca2+ transient (CaT) of murine heart. Significant transmural gradients in Vm and CaT were observed in the left ventricle. Frequency-dependent action potentials and CaT alternans were observed in all ventricular regions with rapid pacing, with significantly greater incidence in the endocardium than epicardium. The observations demonstrate the feasibility of our new approach to cardiac slicing for systematic analysis of intrinsic transmural and regional gradients in Vm and CaT. ABSTRACT: Transmural and regional gradients in membrane potential and Ca2+ transient in the murine heart are largely unexplored. Here, we developed and validated a robust approach which combines transverse ultra-thin cardiac slices and high resolution optical mapping to enable systematic analysis of transmural and regional gradients in transmembrane potential (Vm ) and intracellular Ca2+ transient (CaT) across the entire murine ventricles. The voltage dye RH237 or Ca2+ dye Rhod-2 AM were loaded through the coronary circulation using a Langendorff perfusion system. Short-axis slices (300 µm thick) were prepared from the entire ventricles (from the apex to the base) by using a high-precision vibratome. Action potentials (APs) and CaTs were recorded with optical mapping during steady-state baseline and rapid pacing. Significant transmural gradients in Vm and CaT were observed in the left ventricle, with longer AP duration (APD50 and APD75 ) and CaT duration (CaTD50 and CaTD75 ) in the endocardium compared with that in the epicardium. No significant regional gradients were observed along the apico-basal axis of the left ventricle. Interventricular gradients were detected with significantly shorter APD50 , APD75 and CaTD50 in the right ventricle compared with left ventricle and ventricular septum. During rapid pacing, AP and CaT alternans were observed in most ventricular regions, with significantly greater incidence in the endocardium in comparison with epicardium. In conclusion, these observations demonstrate the feasibility of our new approach to cardiac slicing for systematic analysis of intrinsic transmural and regional gradients in Vm and CaT in murine ventricular tissue.

Heterogeneous distribution of substrates between the endocardium and epicardium promotes ventricular fibrillation in arrhythmogenic right ventricular dysplasia/cardiomyopathy.

Aims: Whether the distribution of scar in arrhythmogenic right ventricular cardiomyopathy (ARVC) plays a role in predicting different types of ventricular arrhythmias is unknown. This study aimed to investigate the prognostic value of scar distribution in patients with ARVC. Methods and results: We studied 80 consecutive ARVC patients (46 men, mean age 47 ± 15 years) who underwent an electrophysiological study with ablation. Thirty-four patients receive both endocardial and epicardial mapping. Abnormal endocardial substrates and epicardial substrates were characterized. Three groups were defined according to the epicardial and endocardial scar gradient (<10%: transmural, 10-20%: intermediate, >20%: horizontal, as groups 1, 2, and 3, respectively). Sinus rhythm electrograms underwent a Hilbert-Huang spectral analysis and were displayed as 3D Simultaneous Amplitude Frequency Electrogram Transformation (SAFE-T) maps, which represented the arrhythmogenic potentials. The baseline characteristics were similar between the three groups. Group 3 patients had a higher incidence of fatal ventricular arrhythmias requiring defibrillation and cardiac arrest during the initial presentation despite having fewer premature ventricular complexes. A larger area of arrhythmogenic potentials in the epicardium was observed in patients with horizontal scar. The epicardial-endocardial scar gradient was independently associated with the occurrence of fatal ventricular arrhythmias after a multivariate adjustment. The total, ventricular tachycardia, and VF recurrent rates were higher in Group 3 during 38 ± 21 months of follow-up. Conclusion: For ARVC, the epicardial substrate that extended in the horizontal plane rather than transmurally provided the arrhythmogenic substrate for a fatal ventricular arrhythmia circuit.

Beamforming algorithms for endocardial border detection.

BACKGROUND: Software-based beamforming which utilizes delay and standard beamforming is a signal processing technique that temporarily stores data from each probe element to improve specular reflections to improve the image resolution. We compared a software algorithm which uses delay and standard beamforming with delay and sum beamforming in standard, hardware to evaluate endocardial borders and need for echo contrast. METHODS: In this prospective study, eligible participants were ≥18 years of age referred clinically for transthoracic echocardiograms. A limited study consisting of three views (apical 4, apical 3, and apical 2 chamber) was performed with the software-based beamforming and standard platform. Number and quality of segments visualized were evaluated using a 17-segment model. Quality of segments was graded as 0 = not visualized, 1 = incompletely visualized, or 2 = completely visualized. Overall quality score for each study (0 = poor, 1 = adequate, 2 = good) was reported. The need for contrast was determined by ASE guidelines. RESULTS: A total of 101 patients (mean age 61 ± 16 years, males 52%) were enrolled. Mean number of segments visualized in apical 4- (6.28 vs 5.65, P < .001), apical 3- (6.27 vs 5.54, P < .001), and apical 2-chamber views (6.26 vs 5.72 P < .001) was higher with the software vs standard platform. The average overall score for image quality was significantly better for the software platform vs standard (1.4 vs 0.9, P =< .001). With the software platform, 23% were judged as requiring contrast as compared with 45% for the standard platform (P < .001). CONCLUSIONS: Delay and standard beamforming in software platform identified more segments with better image quality when compared to the standard high-end platform, decreasing the need for contrast usage.

Left ventricular endocardial longitudinal dysfunction persists after acute myocarditis with preserved ejection fraction.

BACKGROUND: The aim of present study was to assess left ventricular (LV) myocardial deformation and changes over time in patients with acute myocarditis (AM) with preserved ejection fraction detected by late gadolinium enhancement (LGE) magnetic resonance imaging. METHODS: Thirty-five male patients with AM diagnoses and preserved systolic function based on cardiac magnetic resonance imaging (MRI) were prospectively enrolled. On admission, echocardiography with measurements of global and segmental longitudinal (LS) strains was performed both at the endocardial (ENDO) and epicardial (EPI) levels. Findings were compared to 25 control subjects. Twenty-six patients were also monitored over a 22-month follow-up (FU group). RESULTS: On admission, global ENDO-LS was poorer in magnitude in AM (-19.2 ± 3.1) than in controls (-24.0 ± 1.05) (P < 0.0001), whereas EPI-LS was not different (-20.6 ± 3.4 vs -19.7 ± 6 P = NS). A functional increase in magnitude in both ENDO-LS (-20.8 ± 5.4, P = NS) and EPI-LS (-22.6 ± 4.6, P = 0.02) was found in FU vs AM patients. CONCLUSIONS: The present study demonstrates a steady ENDO-LS impairment in infarct-like AM during a 2-year follow-up period, despite a preserved LV ejection fraction.

First-pass myocardial perfusion MRI with reduced subendocardial dark-rim artifact using optimized Cartesian sampling.

PURPOSE: The presence of subendocardial dark-rim artifact (DRA) remains an ongoing challenge in first-pass perfusion (FPP) cardiac magnetic resonance imaging (MRI). We propose a free-breathing FPP imaging scheme with Cartesian sampling that is optimized to minimize the DRA and readily enables near-instantaneous image reconstruction. MATERIALS AND METHODS: The proposed FPP method suppresses Gibbs ringing effects-a major underlying factor for the DRA-by "shaping" the underlying point spread function through a two-step process: 1) an undersampled Cartesian sampling scheme that widens the k-space coverage compared to the conventional scheme; and 2) a modified parallel-imaging scheme that incorporates optimized apodization (k-space data filtering) to suppress Gibbs-ringing effects. Healthy volunteer studies (n = 10) were performed to compare the proposed method against the conventional Cartesian technique-both using a saturation-recovery gradient-echo sequence at 3T. Furthermore, FPP imaging studies using the proposed method were performed in infarcted canines (n = 3), and in two symptomatic patients with suspected coronary microvascular dysfunction for assessment of myocardial hypoperfusion. RESULTS: Width of the DRA and the number of DRA-affected myocardial segments were significantly reduced in the proposed method compared to the conventional approach (width: 1.3 vs. 2.9 mm, P < 0.001; number of segments: 2.6 vs. 8.7; P < 0.0001). The number of slices with severe DRA was markedly lower for the proposed method (by 10-fold). The reader-assigned image quality scores were similar (P = 0.2), although the quantified myocardial signal-to-noise ratio was lower for the proposed method (P < 0.05). Animal studies showed that the proposed method can detect subendocardial perfusion defects and patient results were consistent with the gold-standard invasive test. CONCLUSION: The proposed free-breathing Cartesian FPP imaging method significantly reduces the prevalence of severe DRAs compared to the conventional approach while maintaining similar resolution and image quality. LEVEL OF EVIDENCE: 2 J. Magn. Reson. Imaging 2017;45:542-555.

Persistent fever with chills and an endocardial mass in a child: an unusual presentation of Hughes-Stovin syndrome.

A 12-year-old boy with a right atrium endocardial mass was initially diagnosed as having Lemierre's syndrome on the basis of previous mastoiditis and jugular vein and cerebral venous thrombosis. Lack of response to antibiotics, persistent high fever with chills, acute-phase reactants, and peripheral arterial pseudoaneurysms made us reconsider the diagnosis. Only after the late appearance of radiological pulmonary lesions and recognition of pulmonary artery aneurysms, Hughes-Stovin syndrome was diagnosed. Hughes-Stovin syndrome is an exceedingly rare vasculitis, especially in childhood, consisting of multiple pulmonary artery aneurysms and deep venous thromboses. The lack of formal diagnostic criteria and the rarity of the disease make the diagnosis very challenging, especially when respiratory complaints are not present at onset, as in the presented case. The treatment aims to reduce inflammation, although there is debate about anticoagulation therapy because of the risk of pulmonary haemorrhage.

Left ventricular twist mechanics in the context of normal physiology and cardiovascular disease: a review of studies using speckle tracking echocardiography.

The anatomy of the adult human left ventricle (LV) is the result of its complex interaction with its environment. From the fetal to the neonatal to the adult form, the human LV undergoes an anatomical transformation that finally results in the most complex of the four cardiac chambers. In its adult form, the human LV consists of two muscular helixes that surround the midventricular circumferential layer of muscle fibers. Contraction of these endocardial and epicardial helixes results in a twisting motion that is thought to minimize the transmural stress of the LV muscle. In the healthy myocardium, the LV twist response to stimuli that alter preload, afterload, or contractility has been described and is deemed relatively consistent and predictable. Conversely, the LV twist response in patient populations appears to be a little more variable and less predictable, yet it has revealed important insight into the effect of cardiovascular disease on LV mechanical function. This review discusses important methodological aspects of assessing LV twist and evaluates the LV twist responses to the main physiological and pathophysiological states. It is concluded that correct assessment of LV twist mechanics holds significant potential to advance our understanding of LV function in human health and cardiovascular disease.

Detection of small subendocardial infarction using speckle tracking echocardiography in a rat model.

BACKGROUND: It is challenging to detect small nontransmural infarcts visually or automatically. As it is important to detect myocardial infarction (MI) at early stages, we tested the hypothesis that small nontransmural MI can be detected using speckle tracking echocardiography (STE) at the acute stage. METHODS: Minimal nontransmural infarcts were induced in 18 rats by causing recurrent ischemia-reperfusion of the left anterior descending (LAD) coronary artery, followed by a 30-min ligation and by reperfusion. A week later, the scar size was measured by histological analysis. Each rat underwent three echocardiography measurements: at baseline, 1 day post-MI, and 1 week post-MI. To measure the peak circumferential strain (CS), peak systolic CS, radial strain (RS), and time-to-peak (TTP) of the CS, short-axis view of the apex was analyzed by a STE program. The TTP was normalized by the duration of the heart cycle to create percent change of heart cycle. RESULTS: Histological analysis after 1 week showed scar size of 4±6% at the anterior wall. At 24 h post-MI, the peak CS, peak systolic CS, and RS were reduced compared to baseline at the anterior wall due to the MI, and at the adjacent segments-the anterior septum and lateral wall, due to stunning (P<.05). However, only the anterior wall, the genuine damaged segment, showed prolonged TTP vs baseline (baseline 36%, 24 h 48%, P<.05). CONCLUSION: The TTP of the CS can distinguish between regions adjacent to MI (stunned or tethered) and MI, even in small nontransmural infarcts.

Segmentation of the left ventricular endocardium from magnetic resonance images by using different statistical shape models.

We evaluate in this paper different strategies for the construction of a statistical shape model (SSM) of the left ventricle (LV) to be used for segmentation in cardiac magnetic resonance (CMR) images. From a large database of LV surfaces obtained throughout the cardiac cycle from 3D echocardiographic (3DE) LV images, different LV shape models were built by varying the considered phase in the cardiac cycle and the registration procedure employed for surface alignment. Principal component analysis was computed to describe the statistical variability of the SSMs, which were then deformed by applying an active shape model (ASM) approach to segment the LV endocardium in CMR images of 45 patients. Segmentation performance was evaluated by comparing LV volumes derived by ASM segmentation with different SSMs and those obtained by manual tracing, considered as a reference. A high correlation (r(2)>0.92) was found in all cases, with better results when using the SSM models comprising more than one frame of the cardiac cycle.

Loeffler endocarditis in young woman - a case report.

Loeffler endocarditis is a rare acquired endocardial and myocardial disease characterized by a sharp decrease in the compliance of either or both ventricles with an acute diastolic dysfunction and massive mural thrombosis. This disease is presented in the classification of cardiomyopathies and is a variant of restrictive cardiomyopathy. Today Loeffler endocarditis is considered as a manifestation of hypereosinophilic syndrome with predominant heart involvement. The life-time diagnosis of myocardial injury due to eosinophilic infiltration is rare, or it is diagnosed at the stage of necrotizing endomyocarditis, when the treatment is no longer effective. A number of issues regarding the individual aspects of the pathogenesis of hypereosinophilic syndrome and Loeffler endocarditis are still not fully understood, as well as the long-term prospects for the use of drugs for the treatment of hypereosinophilic syndrome, especially in young and middle-aged persons. Loeffler endocarditis can be suspected in the presence of hypereosinophilia on the background of causeless (unexplainable) hypertrophy of the left ventricle or both ventricles. The article includes a case of the life-time diagnosis of this disease in a young woman with the retrospective analysis of the early stages of the disease, echocardiographic and radiologic imaging at the advanced stage of the disease and quite successful treatment option for this disease.

Feasibility of perflutren microsphere contrast transthoracic echocardiography in the visualization of ventricular endocardium during venovenous extracorporeal membrane oxygenation in a validated ovine model.

BACKGROUND: Transthoracic echocardiography (TTE) during extra corporeal membrane oxygenation (ECMO) is important but can be technically challenging. Contrast-specific TTE can improve imaging in suboptimal studies. These contrast microspheres are hydrodynamically labile structures. This study assessed the feasibility of contrast echocardiography (CE) during venovenous (VV) ECMO in a validated ovine model. METHOD: Twenty-four sheep were commenced on VV ECMO. Parasternal long-axis (Plax) and short-axis (Psax) views were obtained pre- and postcontrast while on VV ECMO. Endocardial definition scores (EDS) per segment were graded: 1 = good, 2 = suboptimal 3 = not seen. Endocardial border definition score index (EBDSI) was calculated for each view. Endocardial length (EL) in the Plax view for the left ventricle (LV) and right ventricle (RV) was measured. RESULTS: Summation EDS data for the LV and RV for unenhanced TTE (UE) versus CE TTE imaging: EDS 1 = 289 versus 346, EDS 2 = 38 versus 10, EDS 3 = 33 versus 4, respectively. Wilcoxon matched-pairs rank-sign tests showed a significant ranking difference (improvement) pre- and postcontrast for the LV (P < 0.0001), RV (P < 0.0001) and combined ventricular data (P < 0.0001). EBDSI for CE TTE was significantly lower than UE TTE for the LV (1.05 ± 0.17 vs. 1.22 ± 0.38, P = 0.0004) and RV (1.06 ± 0.22 vs. 1.42 ± 0.47, P = 0.0.0006) respectively. Visualized EL was significantly longer in CE versus UE for both the LV (58.6 ± 11.0 mm vs. 47.4 ± 11.7 mm, P < 0.0001) and the RV (52.3 ± 8.6 mm vs. 36.0 ± 13.1 mm, P < 0.0001), respectively. CONCLUSIONS: Despite exposure to destructive hydrodynamic forces, CE is a feasible technique in an ovine ECMO model. CE results in significantly improved EDS and increased EL.