The Importance of International Normalized Ratio Monitoring in Patients With Mechanical Pulmonary Valve Prosthesis

Background

The most challenging risk of mechanical valves is thromboembolic events; therefore, life-long anticoagulation therapy is necessary. Anticoagulation therapy should be adjusted for each patient with serial international normalized ratio (INR) monitoring. Due to the small number of patients with a mechanical valve in the pulmonary position, we are facing a lack of information about the therapeutic range of the INR in these patients. We aimed to evaluate patients with a history of pulmonary valve replacement (PVR) who faced malfunction and compare their INR and echocardiographic data at the time of malfunction and 3 months prior.

Methods

In this cross-sectional study, 71 patients who had previously undergone PVR and presented to Shaheed Rajaie Cardiovascular Medical and Research Center with a diagnosis of pulmonary valve malfunction between 2014 and 2021 were included. Patients' INR and echocardiographic data at the time of the malfunction and 3 months before the malfunction diagnosis were gathered from the hospital's registry. IBM SPSS 20.0 was used for data analysis.

Results

In this cross-sectional study, 71 patients with mechanical pulmonary valve malfunction were included. 49.3% (n = 35) were men, 50.7% (n=36) were women, and their mean age was 33.23 (±8.279). The mean INR of all patients 3 months before malfunction and at the time of malfunction was 2.29 (±0.753) and 2.20 (±0.704), respectively.

Conclusion

In this study, most of our patients had an INR below the therapeutic range, both at the time of malfunction and 3 months prior. It emphasizes the importance of patient follow-up and keeping the INR in the therapeutic range.

Right Ventricular Function Indices at Rest and During Exercise in Hyperthyroid Patients: A Cross-sectional Study

Background

Since hyperthyroidism could be associated with right ventricular dysfunction, this study intended to investigate right ventricular (RV) function using strain echocardiography in hyperthyroid patients both at rest and in maximum-stress conditions.

Methods

This cross-sectional study was conducted at Rajaie Cardiovascular Medical and Research Center, Tehran, Iran, from January 2019 to January 2020. All study participants completed a maximum treadmill exercise test, as well as a complete two-dimensional echocardiogram at rest and the peak of stress test. The data were analyzed using SPSS statistical software. The independent samples t test and Mann-Whitney U test were used for numerical, and the Chi square test was used for nominal variables. P<0.05 was considered statistically significant.

Results

The final analysis included 52 participants (26 subjects in each group). In a maximal stress situation, we found that among the RV function indices, RV global longitudinal strain (P=0.0001), systolic strain rate (P=0.0001), diastolic strain rate (P=0.0002), and tricuspid annular plane systolic excursion (P=0.019) were reduced significantly in the hyperthyroid patients compared to the control group. There was also a linear correlation between RV size and thyroid stimulating hormone (TSH) level (P=0.009, r=0.36). Moreover, we found a negative linear correlation between TSH level with maximum stress RV strain and diastolic strain rate (P<0.001).

Conclusion

The findings of the present study revealed a significant change in RV function indices among hyperthyroid patients. Therefore, it highlights the necessity of early diagnosis and treatment of hyperthyroidism, as well as RV function evaluation in these patients.

Diffuse alveolar hemorrhage; An under-diagnosed and rare complication of glycoprotein IIb/IIIa inhibitors

Glycoprotein IIb/IIIa inhibitors play a key role in the treatment of patients who have acute coronary syndromes and undergone percutaneous coronary intervention. However, its serious complication is diffused alveolar hemorrhage. A 73-year-old diabetic woman presented with chest pain and dynamic ST elevation in ECG and positive troponin. She had occlusion in two coronary arteries and underwent percutaneous coronary intervention. The eptifibatide was administered. After hours, she showed respiratory symptoms, as well as drop of blood pressure and hemoglobin. All differential diagnoses suggested for her clinical presentation were evaluated, and finally, on the sixth day diffuse alveolar hemorrhage was diagnosed. Although respiratory symptoms such as hemoptysis and dyspnea may occur as complications of pulmonary edema and/or pneumonia, assumed clinical suspicion for pulmonary hemorrhage leading to early detection of it. Moreover, there is no definitive guideline for decreased bleeding complications and treatment of alveolar hemorrhage caused by glycoprotein IIb/IIIa receptor inhibitors.

A case of early thrombosis following a percutaneous tricuspid valve in valve implantation managed by thrombolysis

Bioprosthetic valve thrombosis (BPVT) is a growing recognized entity, especially with the increasing use of the valve in vale procedures and the advent of new detection technologies (e.g., 4D CT and 4D echocardiography). The incidence of BPVT is higher in transcatheter valves than surgically implanted bioprosthetic valves. However, the best thromboprophylaxis regimen and optimal management strategy in the acute context remain unknown. This paper presents a case of early thrombosis following the percutaneous tricuspid valve in vale procedure that was successfully managed with thrombolysis.

The Role of Left Atrial Strain in Detecting Left Ventricular Diastolic Dysfunction: Comparison between the 2009 and 2016 Recommendations

Background: The frequency of left ventricular diastolic dysfunction (DD) is overestimated by earlier recommendations. We compared the 2009 and 2016 guidelines regarding the detection of DD and explored the potential of adding left atrial (LA) strain to the current guideline.

Methods: Consecutive patients with heart failure were enrolled. All the patients were examined using 2-dimensional speckle-tracking echocardiography (2D-STE) and tissue Doppler imaging. DD was evaluated in terms of E/eʹ, eʹ velocity, E, A, tricuspid regurgitation velocity, LA volume, and LA strain.

Results: This study evaluated 147 patients (101 males, 68.7%) at a mean age of 54.73±14.42 years. LA strain decreased with increasing grades of DD in both guidelines. The rate of reclassification between the 2 guidelines was 41%. The detection rate of normal diastolic function increased after the implementation of the 2016 guideline. LA strain discriminated individuals with normal diastolic function from those with DD more accurately than did LA volume index (area under the curve [AUC] =0.816 vs AUC=0.759, respectively). When LA strain <23% was incorporated into the 2016 guideline, 2 out of 4 patients with indeterminate diastolic function were reclassified as normal and 2 patients as grade I DD. The rate of reclassification was 4.1% after the addition of LA strain to the current guideline (κ=0.939, P<0.001).

Conclusion: This study showed that the current guideline detected lower rates of DD than did the earlier recommendations. Furthermore, the incorporation of LA strain into the current guideline resulted in lower rates of indeterminate diastolic function.

Echocardiography image enhancement using texture-cartoon separation

Due to the speckled nature of cardiac ultrasound imaging, it is not easy to process and extract useful information directly from the acquired image. In this work, we have proposed a method to reduce the effect of speckle artifacts through the decomposition of echocardiography images into cartoon and texture components. The first component (i.e., cartoon image) contains image structures containing smooth areas and sharp edges, and the texture component is mainly composed of highly oscillating and repetitive patterns. To decompose the image into these two subcomponents, convolutional sparse coding has been utilized as a solid tool for solving the decomposition optimization function. The significant advantage of using convolutional sparse coding, compared to classical sparse coding methods, is image quality enhancement due to not using the block coding, making the classic solutions computationally feasible. The original image has been masked with the cartoon part leading to suppress speckle artifacts which result in image quality enhancement. Besides, it has been shown that using this speckle reduction scenario, considerable accuracy enhancement of the segmentation task can be achieved, compared to segmentation of the original image. Numerical results provide acceptable reasons to prove the efficiency of the proposed algorithm. Resulting echocardiography videos show a mean segmentation enhancement of 15.98 for Hausdorff distance (in pixels) and 0.0632 for the Dice similarity coefficient.

Comparison of myocardial deformation indices during rest and after activity in untreated hyperthyroid patients with normal population

BACKGROUND

Thyroid hormones play an essential role on the cardiovascular system. Also, thyroid diseases have a prominent adverse effect on myocardial and vascular functions. Therefore, the aim of this study was to compare myocardial deformation indices during resting and after activity between the untreated hyperthyroid patients and normal population.

METHODS

We included 26 untreated participants who were newly diagnosed with hyperthyroidism and 26 healthy participants matched in terms of age and sex. The left ventricular end-diastolic volume index (LVEDVI), Heart Rate (HR), Cardiac Output (CO), systolic and diastolic blood pressures, Global Longitudinal Strain (GLS), Global Circumferential Strain (GCS), Rate-Pressure Product (RPP), systolic and diastolic strains rates were measured in rest and peak of exercise in stress echocardiography.

RESULTS

Age and sex distributions were similar among the groups. Also, mean serum TSH was 0.08 ± 0.08 ng/dL in the case group. The participants with the untreated hyperthyroidism had lower Ejection Fraction change (ΔEF), GLS, peak stress systolic and diastolic strains rates compared to the control group. Also, there was a positive association between TSH levels and basal HR, RPP, CO, as well as a negative correlation with basal and maximum GLS, ΔHR, ΔEF, and ΔCO. Also, a duration of symptoms had a linear association with rest HR, CO, and LVEDVI, as well as a negative correlation with rest and maximal GLS, ΔHR, and ΔGLS.

CONCLUSION

Myocardial deformation assessed by 2DE imaging are significantly impaired in the hyperthyroid patients. In this regard, further studies with a larger sample size are required to confirm the results of this study.

Tricuspid valve geometry in patients with functional tricuspid regurgitation: A three-dimensional echocardiographic study

INTRODUCTION

Tricuspid valve (TV) has a complex anatomy causing some difficulties in echocardiographic evaluation. In this study, we sought to assess the geometry of TV in patients with functional tricuspid regurgitation (TR) by the implementation of 2- and 3-dimennsional (2D and 3D) echocardiography.

METHODS

In a case-control study, the geometrical features of TV were evaluated in forty patients with functional TR using echocardiographic examinations, and those data compared with twenty-five age- and sex-matched healthy individuals.

RESULTS

The mean age of patients was 50 ± 12 years, and 75% were female. All echocardiographic features of TV geometry were significantly greater in TR compared to control group. The 3D evaluation of TV annulus showed that the annulus shape was more circular in the TR compared to the control group. When compared patients with moderate and severe TR, there was a significant difference between groups regarding the size of the TV septolateral annulus diameter (3.5 ± 0.4 vs 3.9 ± 0.7 cm; P = .048), and the angle between mitral valve and TV annuluses (12.5 ± 4.3 vs 17 ± 9º; P = .048). Tenting areas measured by 2D echocardiography and obtained by TomTec software were significantly greater in severe TR compared to moderate TR group. The diameter of TV by 2D echocardiography was significantly higher in atrial fibrillation than that in sinus rhythm group among patients with TR.

CONCLUSIONS

The implementation of 3D echocardiography is useful in the determination of TV geometry in patients with functional TR. The accurate evaluation of anatomical features of TV might provide valuable tools in the evaluation of patients with functional TR.

Assessment of normal hemodynamic profile of mechanical pulmonary prosthesis by doppler echocardiography: a prospective cross-sectional study

Objectives

Very few reports have described the Doppler-derived echocardiographic parameters for mechanical pulmonary valve prosthesis (MPVP). This study aims to describe the normal Doppler hemodynamic profile of MPVP using Doppler echocardiography.

Methods

The current prospective, single center observational study enrolled 108 patients who underwent pulmonary valve replacement (PVR) surgery for the first time and had a normally functioning prosthesis post-operation. The hemodynamic performance of MPVPs, considering flow dependent and flow independent parameters, was evaluated at two follow-up points, at week one and week four post-operation. All assessments were conducted by an experienced echocardiographer.

Results

The mean age (±SD) of the participants was 26.4 (±8.98). Tetralogy of Fallot (ToF) was the most common underlying disease leading to PVR, with a prevalence of 88%. At first week post-operation, measurement of indices reported the following values (±SD): peak pressure gradient (PPG): 18.51(±7.64) mm Hg; mean pressure gradient (MPG): 10.88(±5.62) mm Hg; peak velocity (PV): 1.97(±0.43)m/s; doppler velocity index (DVI): 0.61(±18); pulmonary velocity acceleration time (PVAT): 87.35(±15.16) ms; effective orifice area (EOA): 2.98(±1.02) cm²;and effective orifice area to body surface area ratio (EOA/ BSA): 1.81(±0.62) cm²/m². Comparing these measurements with those obtained from the second follow-up (at week four post-op) failed to hold significant difference in all values except for PVAT, which had increased from its primary value (p = 0.038). Also, right ventricular (RV) function showed significant improvement throughout the follow up period.

Conclusion

The findings of this study help strengthen the previously scarce data pool and better establish the normal values for Doppler hemodynamics in mechanical pulmonary prosthesis.

Temporal Super-resolution of Ultrasound Imaging Using Matrix Completion

The temporal super-resolution of the dynamic ultrasound imaging, a means to observe rapid heart movements, is considered an important subject in medical diagnosis of cardiac conditions. Here, a new technique based on the acquisition scheme using the matrix completion (MC) theory is offered for the temporal super-resolution of the two-dimensional (2D) and three-dimensional (3D) ultrasound imaging. MC mentions the problem of completing a low-rank matrix when only a subset of its elements can be observed. Here, the lower scan lines are acquired. Whereby, the proposed method uses temporal and spatial information of the radio frequency (RF) image sequences for the reconstruction of skipped RF lines. This is performed using the construction of the MC images and then reconstruction of them by the MC theory. The results of the proposed method are compared with the compressive sensing (CS) reconstruction methods. The qualitative and quantitative evaluations of 2D and 3D data demonstrate that in the proposed method, which uses the spatial and temporal relation of RF images and the MC theory, the reconstruction is more accurate, and the reconstruction error is lower. The computational complexity of this method is very low. It also does not require hardware adjustments. Therefore, it can be easily implemented in current ultrasound-imaging devices with the frame-rate enhancement. For instance, the frame rate up to two times the original sequence is feasible using the proposed methods, while root mean square error is decreased by about 35% and 30% for 2D and 3D data, respectively, compared with the CS reconstruction method.

The effect of colchicine on the echocardiographic constrictive physiology after coronary artery bypass graft surgery

BACKGROUND

Constrictive physiology is a transitory condition that could lead to constrictive pericarditis, which is a rare complication after open-heart surgery. Anti-inflammatory drugs like colchicine are recommended for prevention of constrictive pericarditis; however, there is no evidence about the effect of colchicine on constrictive pericarditis. Thus, the aim of this study is to evaluate the preventive effect of colchicine on the incidence of echocardiographic constrictive physiology after open-heart surgery.

METHODS

This was a parallel randomized, double-blind trial. Patients were randomly assigned to receive 1 mg colchicine once-daily from 48 hours before and 0.5 mg twice daily for 5 days after surgery. Primary outcome was the incidence of the constrictive physiology after primary endpoint (1 week after the surgery). The secondary outcome was the primary outcome after secondary endpoint (4 weeks after surgery) plus the new cases of constrictive physiology between the primary and secondary endpoints.

RESULTS

Out of 160 participating patients, the primary outcome occurred in 19 patients (23%) in placebo and 11 (13%) in intervention groups. There was no significant difference between two groups (P = .106). After 4 weeks of follow-up, 19 patients (23%) in placebo and 9 (11%) in intervention groups had constrictive physiology whereas 2 out of 11 patients (18.2%) were recovered. The difference was significant (P = .038). No new case of constrictive physiology occurred between primary and secondary endpoints.

CONCLUSION

Short-term use of colchicine has a preventive effect on reducing constrictive physiology after 1 month of open-heart surgery but not a week after that.

Concomitant cardiac and hepatic hemangiomas

Primary tumors of the heart are rare with a reported incidence of about 0.002% to 0.3% at autopsy. A cardiac hemangioma is a form of benign primary cardiac tumor that often presents with atypical clinical symptoms. Hemangiomas are generally isolated lesions. Here, we report a patient with previous hepatic hemangioma who later was found to have a large coexistent cardiac hemangioma presenting with cardiac compressive symptoms.

Rapid improvement in right ventricular free wall longitudinal strain measures after successful percutaneous mitral commissurotomy

BACKGROUND

Percutaneous mitral commissurotomy (PMC) is currently the treatment of choice for patients with symptomatic mitral stenosis (MS) that have favorable valvular characteristics. We aimed to evaluate the effect of PMC on the longitudinal strain of the right ventricular (RV) free wall in patients with severe MS.

METHODS

This prospective study recruited patients who underwent PMC. Transesophageal and transthoracic echocardiographic examinations were performed. The mitral valve area (MVA) was measured by three-dimensional evaluation. The RV longitudinal strain was measured via the speckle-tracking method.

RESULTS

A total of 42 patients with a maximum MVA of 1.5 cm² underwent PMC in our study. The MVA increased significantly after the procedure (pre-PMC MVA = 0.94 ± 0.20 cm² vs post-PMC MVA = 1.45 ± 0.18 cm² ; P < .01). Systolic pulmonary artery pressure decreased from 46.05 ± 14.08 mm Hg preprocedurally to 35.86 ± 7.53 mm Hg postprocedurally (P < .01). The mean RV free wall longitudinal strain was -19.00 ± 5.14%, which rose significantly after PMC to -20.97 ± 3.81 (P < .05). There were postprocedural increases, albeit nonsignificant, in the tricuspid annular peak systolic excursion, the peak systolic Doppler velocity of the RV free wall, and fractional area change. The improvement in the RV longitudinal strain was more prominent in the patients with an MVA of less than 1.0 cm² .

CONCLUSIONS

There was a significant post-PMC rise in the RV free wall longitudinal strain measures in our study population, demonstrating an immediate improvement in the RV systolic function of the patients.

Morphologic and functional features of left atrial appendage in Iranian population: an echocardiographic study

Introduction: Cardioembolic events are accompanied by left atrial appendage (LAA) in patients suffering from atrial fibrillation (AF); therefore, the LAA closure is implemented as a preventive strategy. The detection of LAA morphologies and function is a paramount step before establishing the LAA closure. Herein, we sought to determine the morphologic features of the LAA in an Iranian population using echocardiographic evaluation.

Methods: Seventy-two near-normal heart patients were investigated by conducting a cross-sectional study. All patients were examined using the 2-dimensional and 3-dimensional transesophageal echocardiography (2D- and 3D-TEE) method. The anatomical features and functions of LAA were examined. All images were stored and analyzed offline.

Results: The patients’ mean age was 39 ± 15.5 year and 33 (45.8%) were female. The most frequent shape of LAA was wind sock . More LAA lobes was observed in patients with AF compared to those with NSR. In comparison with AF group, the NSR had higher LAA flow velocity (P < 0.01). The paroxysmal AF had greater LAA flow velocity and LAA ejection fraction in comparison with the chronic AF (39 ± 19 vs. 75 ± 22, P < 0.01; and 49±4 vs. 72±14, P < 0.003; respectively). The paroxysmal AF had smaller systolic LAA orifice area in comparison with the chronic AF (P < 0.02).

Conclusion: The morphologic features of LAA in Iranian population were within the range of other studies and LAA length and orifice diameters in 2D- and 3D-TEE were consistent. In addition, AF influenced the morphologies and functions of LAA compared to sinus rhythm.

Asymptomatic young man with an incidental murmur

CLINICAL INTRODUCTION

A 32-year old man was referred to our institution for transthoracic echocardiography (TTE) following detection of an incidental murmur on physical examination before blood donation. He was asymptomatic with no significant medical history. Physical examination revealed dual heart sounds with a grade II/VI systolic murmur heard in the left sternal border. An ECG was in normal sinus rhythm. TTE was performed (figure 1A-C, online supplementary videos 1-4) followed by cardiac CT angiography (CTA) (figure 1D,E).heartjnl;104/15/1307/F1F1F1Figure 1(A) Transthoracic echocardiography, parasternal left ventricular long axis view. (B) Colour Doppler of modified short axis in the mid-left ventricular level. (C) Doppler flow velocity profile. (D) Cardiac CT angiography (CTA) sagittal reconstruction. (E) Three-dimensional CTA reconstruction of the heart.

QUESTION

What is the diagnosis?Pericardial cyst.Ventricular septal defect.Kawasaki.Anomalous left coronary artery from pulmonary artery (ALCAPA).

Quantification of Left Ventricle Function in Stress Echocardiography Using Endocardial Area Centroid Trajectory

Coronary artery occlusion has a direct effect on cardiac activity and is a well-known reason for ventricular motion disorder, specifically left ventricle (LV) wall motion dysfunction. In stress echocardiography, wall motion abnormality is exaggerated when stress is applied to the heart, and therefore, it is easier to diagnose abnormality in ventricular motion. In this study, we have presented a new parameter that measures LV function. We have shown that LV function can be measured using a variation of endocard borders during a cardiac cycle in standard stress echocardiography frames. This parameter shows a meaningful difference between ischemic and normal hearts and is calculated at different heart rates (HRs). In conclusion, ischemic hearts cannot keep up with the required increase in activity when reaching peak levels of stress.

Outcome of Sub-Massive Pulmonary Thromboemboli in Patients Who Received Thrombolytic and or Non-Thrombolytic Therapy

Background

Thrombolytic therapy in patients with sub-massive pulmonary embolism (SMPTE) needs further assessment.

Objectives

The current study aimed to assess a potential benefit of thrombolytic and non-thrombolytic therapy in patients with SMPTE.

Patients and Methods

One hundred-nineteen patients were enrolled with SMPTE from 2006 to 2010 in the tertiary care center of Rajaie medical and research center. The patients who had pulmonary thromboemboli (PTE) and received thrombolytic plus heparin therapy and or non-thrombolytic (unfractionated heparin alone) were evaluated for hemodynamic changes (blood pressure, pulse rate, pulmonary artery systolic pressure, right ventricular failure and right ventricle enlargement), before and after 48 hours of treatment. The mortality rate was also assessed.

Results

Forty-five percent of the patients with SMPTE received thrombolytic therapy (streptokinase) and 55% of SMPTE patients received non-thrombolytic therapy (unfractionated heparin). Pulse rate, pulmonary arterial pressure and tricuspid regurgitation gradient in patients receiving thrombolytic therapy reduced significantly (P = 0.001, P = 0.01 and P = 0.001, respectively). There was no significant difference before and after treatment regarding systolic blood pressure (P = 0.4), diastolic blood pressure (DBP) (P = 0.5), systolic arterial pressure (SPAP) (P = 0.1), Right ventricular (RV) function (P = 0.1) and RV size (P = 0.1). In patients who received a non-thrombolytic therapy, there were no significant differences between the groups regarding SBP (P = 0. 2), DBP ( P= 0. 4) and PR (P = 0. 1), SPAP (P = 0.6), TRG (P = 0.4), RV function (P = 0.4) and RV size (P = 0.2) before and after treatment. There were no significant differences between the groups according to mortality rate.

Conclusions

Thrombolytic therapy lead to earlier relief of hemodynamic condition in comparison to non-thrombolytic therapy but no changes were observed in mortality rate.

Comparison of Gated SPECT Myocardial Perfusion Imaging with Echocardiography for the Measurement of Left Ventricular Volumes and Ejection Fraction in Patients With Severe Heart Failure

Background:

Gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is known as a feasible tool for the measurement of left ventricular ejection fraction (EF) and volumes, which are of great importance in the management and follow-up of patients with coronary artery diseases. However, considering the technical shortcomings of SPECT in the presence of perfusion defect, the accuracy of this method in heart failure patients is still controversial.

Objectives:

The aim of the present study was to compare the results from gated SPECT MPI with those from echocardiography in heart failure patients to compare echocardiographically-derived left ventricular dimension and function data to those from gated SPECT MPI in heart failure patients.

Patients and Methods:

Forty-one patients with severely reduced left ventricular systolic function (EF ≤ 35%) who were referred for gated SPECT MPI were prospectively enrolled. Quantification of EF, end-diastolic volume (EDV), and end-systolic volume (ESV) was performed by using quantitative gated spect (QGS) (QGS, version 0.4, May 2009) and emory cardiac toolbox (ECTb) (ECTb, revision 1.0, copyright 2007) software packages. EF, EDV, and ESV were also measured with two-dimensional echocardiography within 3 days after MPI.

Results:

A good correlation was found between echocardiographically-derived EF, EDV, and ESV and the values derived using QGS (r = 0.67, r = 0.78, and r = 0.80 for EF, EDV, and ESV, respectively; P < 0.001) and ECTb (r = 0.68, 0.79, and r = 0.80 for EF, EDV, and ESV, respectively; P < 0.001). However, Bland-Altman plots indicated significantly different mean values for EF, 11.4 and 20.9 using QGS and ECTb, respectively, as compared with echocardiography. ECTb-derived EDV was also significantly higher than the EDV measured with echocardiography and QGS. The highest correlation between echocardiography and gated SPECT MPI was found for mean values of ESV different.

Conclusions:

Gated SPECT MPI has a good correlation with echocardiography for the measurement of left ventricular EF, EDV, and ESV in patients with severe heart failure. However, the absolute values of these functional parameters from echocardiography and gated SPECT MPI measured with different software packages should not be used interchangeably.

Temporal Super Resolution Enhancement of Echocardiographic Images Based on Sparse Representation

A challenging issue for echocardiographic image interpretation is the accurate analysis of small transient motions of myocardium and valves during real-time visualization. A higher frame rate video may reduce this difficulty, and temporal super resolution (TSR) is useful for illustrating the fast-moving structures. In this paper, we introduce a novel framework that optimizes TSR enhancement of echocardiographic images by utilizing temporal information and sparse representation. The goal of this method is to increase the frame rate of echocardiographic videos, and therefore enable more accurate analyses of moving structures. For the proposed method, we first derived temporal information by extracting intensity variation time curves (IVTCs) assessed for each pixel. We then designed both low-resolution and high-resolution overcomplete dictionaries based on prior knowledge of the temporal signals and a set of prespecified known functions. The IVTCs can then be described as linear combinations of a few prototype atoms in the low-resolution dictionary. We used the Bayesian compressive sensing (BCS) sparse recovery algorithm to find the sparse coefficients of the signals. We extracted the sparse coefficients and the corresponding active atoms in the low-resolution dictionary to construct new sparse coefficients corresponding to the high-resolution dictionary. Using the estimated atoms and the high-resolution dictionary, a new IVTC with more samples was constructed. Finally, by placing the new IVTC signals in the original IVTC positions, we were able to reconstruct the original echocardiography video with more frames. The proposed method does not require training of low-resolution and high-resolution dictionaries, nor does it require motion estimation; it does not blur fast-moving objects, and does not have blocking artifacts.

Diagnostic accuracy of myocardial deformation indices for detecting high risk coronary artery disease in patients without regional wall motion abnormality

BACKGROUND

The prediction of coronary artery disease (CAD) by conventional echocardiographic measurements is principally based on the estimation of ejection fraction and regional wall motion abnormality (RWMA). This study aimed to determine whether strain echocardiography of left ventricle measured by velocity vector imaging (VVI) method could detect patients with a high-risk CAD.

METHODS

In a prospective study, a total of 119 consecutive patients who were assessed for eligibility were categorized into three groups: (1) without CAD as normal (n=59), (2) 1- or 2-vessel disease as low-risk (n=29), and (3) left main and/or 3-vessel disease as high-risk (n=31). The peaks of systolic strain and strain rate from 18 curves of apical views were averaged as global longitudinal strain and strain rate (GLS and GLSR), respectively; the 6 systolic peaks of strain and strain rate at base- and mid-ventricular of short axis views were averaged as mean radial strain rate (MRSR).

RESULTS

GLS, GLSR, and basal MRSR of left ventricle were significantly lower in the high-risk group (P=0.047, P=0.004 and P=0.030, respectively). Receiver operating characteristics curve showed that the optimal values of GLS, GLSR, and basal MRSR for detecting the severe CAD were -17%, -1 s(-1), and 1.45 s(-1) with the sensitivities of 77%, 71%, and 71% and the specificities of 63%, 67%, and 62%, respectively.

CONCLUSION

Decrements in the GLS, GLSR, and basal MRSR of the left ventricle can detect the high-risk CAD cases among patients without RWMA at rest.

Assessment of left ventricular mechanical dyssynchrony by phase analysis of gated-SPECT myocardial perfusion imaging and tissue Doppler imaging: comparison between QGS and ECTb software packages

BACKGROUND

Recently, the phase analysis of gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) has become feasible via several software packages for the evaluation of left ventricular mechanical dyssynchrony. We compared two quantitative software packages, quantitative gated SPECT (QGS) and Emory cardiac toolbox (ECTb), with tissue Doppler imaging (TDI) as the conventional method for the evaluation of left ventricular mechanical dyssynchrony.

METHODS AND RESULTS

Thirty-one patients with severe heart failure (ejection fraction ≤35%) and regular heart rhythm, who referred for gated-SPECT MPI, were enrolled. TDI was performed within 3 days after MPI. Dyssynchrony parameters derived from gated-SPECT MPI were analyzed by QGS and ECTb and were compared with the Yu index and septal-lateral wall delay measured by TDI. QGS and ECTb showed a good correlation for assessment of phase histogram bandwidth (PHB) and phase standard deviation (PSD) (r = 0.664 and r = 0.731, P < .001, respectively). However, the mean value of PHB and PSD by ECTb was significantly higher than that of QGS. No significant correlation was found between ECTb and QGS and the Yu index. Nevertheless, PHB, PSD, and entropy derived from QGS revealed a significant (r = 0.424, r = 0.478, r = 0.543, respectively; P < .02) correlation with septal-lateral wall delay.

CONCLUSION

Despite a good correlation between QGS and ECTb software packages, different normal cut-off values of PSD and PHB should be defined for each software package. There was only a modest correlation between phase analysis of gated-SPECT MPI and TDI data, especially in the population of heart failure patients with both narrow and wide QRS complex.

A rare case of right-sided heart failure after bentall procedure

Pseudoaneurysms of the ascending aorta, which are rare and life-threatening complications in cardiovascular surgeries, can be caused by the Bentall procedure. We describe a 44-year-old woman, who had a medical history of acute aortic dissection (Type A) and the Bentall procedure and was admitted because of exertional dyspnea, edema of the lower extremities, ascites, and holosystolic murmur in the left lower sternal border. Preoperative echocardiography revealed a pseudoaneurysm of the ascending aorta and fistulization of the pseudoaneurysm to the right atrium. Multi-slice computed tomographic scan also showed a large pseudoaneurysm of the ascending aorta around the tube graft. The patient underwent surgery, during which the pseudoaneurysm was resected, the ostium of the right coronary artery was reimplanted, and the orifice of the right atrial fistula was sutured. Intraoperative transesophageal echocardiography revealed the perfect result of the surgery. The patient was discharged uneventfully.

Normal reference values of tissue Doppler imaging parameters for right ventricular function in young adults: a population based study

Background:

Tissue Doppler imaging is used routinely to quantify both left and right ventricular function. However, normal reference values of echocardiography parameters of the right ventricle in Iranian population are still unknown.

Objectives:

Accordingly, we conducted a study to determine the normal values of echocardiography parameters of right ventricular function in a healthy Iranian population.

Patients and Methods:

One hundred and eighty seven healthy volunteer subjects enrolled. Normal subjects were chosen by taking into account history, physical examination, ECG and echocardiography.

Results:

Reference ranges (5th and 95th percentile values) for tricuspid E velocity, A velocity, E/A ratio, deceleration time, annular Sa velocity, Ea velocity, and E/Ea ratio were derived for the whole individuals and for each of the three age groups (< 30, 30–39, 40-49). The deceleration time, E/ Ea ratio and acceleration time of the iso-volumetric contraction time (IVA) were greater in male than in female. All measured parameters were bigger but not statistically significant in the 40-49 year-old group in comparison with the < 30 year-old group. Comparison of data between different groups showed no significant differences between the majority of data when they have been adjusted to body surface area, age and sex.

Conclusions:

The reference ranges presented for the echocardiography parameters of right ventricular function, albeit not conducted in a sizable sample of normal cases, will help to standardize the assessment of RV functions, particularly by tissue Doppler imaging.

An efficient electrochemical synthesis of diamino-o-benzoquinone: Mechanistic and kinetic evaluation of the reaction of azide ion with o-benzoquinone

An efficient method for the synthesis of diamino-o-benzoquinone based on the Michael reaction of electrochemically generated o-benzoquinone with azide ion is described, as well as an estimation of the homogeneous rate constant (k(obs)) of the reaction of o-benzoquinone with azide ion by the digital-simulation method.