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Fulltext Doppler echocardiography guided cardiac resynchronization therapy in heart failure

Oemar, Hamed, Abdulgani, Hafil Budianto

Medical Health Reviews, 2008;2008(1):17-28.
MyJurnal

Heart failure (HF) is a major burden in almost all countries. The prevalence of symptomatic HF is still high. Despite our best understanding of its pathophysiologic mechanisms and the recent advances in pharmacologic therapy, it remains a highmortality and morbidity disease. About 30-50% of patients with HF have concurrent electrical delay in the electrocardiogram (ECG), mainly in the form of LBBB.1 This kind of conduction delay commonly occurs in patients with idiopathic dilated cardiomyopathy and ischemic cardiomyopathy as well. The abnormality of left ventricle (LV) conduction will lead to a change in LV contraction pattern resulting dyssynchronized with right ventricle) contraction. Thus, a dyssynchronous LV contractile pattern usually manifested by late activation of the LV lateral wall which in turn impairs LV systolic function, reduces cardiac output, raises filling pressure and worsens mitral regurgitation2. Cardiac resynchronization therapy (CRT) improves cardiac function and exercise capacity leading to an improved survival in patients with advanced heart failure and ventricular conduction delay.3 The underlying mechanisms of these beneficial effects are not fully understood, but they appear to be related to a restored coordination of the left (LV) and right ventricular (RV) contraction and relaxation.4 These effects may directly lead to augmented contractility and reduction of LV filling pressures.5 Echocardiography has been widely used to identify patients who are candidates for CRT and to monitor the response in LV function at follow-up after device implantation. This review addresses the applications of CRT in patients with moderate– severe heart failure and the role of echocardiography in optimizing CRT including patient selection, risk and benefit of CRT and appropriate measures.

Matched MeSH terms: Ventricular Function, Left
A method for control of an implantable rotary blood pump for heart failure patients using noninvasive measurements

Lim E, Alomari AH, Savkin AV, Dokos S, Fraser JF, Timms DL, et al.

Artif Organs, 2011 Aug;35(8):E174-80.
PMID: 21843286 DOI: 10.1111/j.1525-1594.2011.01268.x

We propose a deadbeat controller for the control of pulsatile pump flow (Q(p) ) in an implantable rotary blood pump (IRBP). Noninvasive measurements of pump speed and current are used as inputs to a dynamical model of Q(p) estimation, previously developed and verified in our laboratory. The controller was tested using a lumped parameter model of the cardiovascular system (CVS), in combination with the stable dynamical models of Q(p) and differential pressure (head) estimation for the IRBP. The control algorithm was tested with both constant and sinusoidal reference Q(p) as input to the CVS model. Results showed that the controller was able to track the reference input with minimal error in the presence of model uncertainty. Furthermore, Q(p) was shown to settle to the desired reference value within a finite number of sampling periods. Our results also indicated that counterpulsation yields the minimum left ventricular stroke work, left ventricular end diastolic volume, and aortic pulse pressure, without significantly affecting mean cardiac output and aortic pressure.

Matched MeSH terms: Ventricular Function, Left
Enhanced optical flow field of left ventricular motion using quasi-Gaussian DCT filter

Riyadi S, Mustafa MM, Hussain A, Maskon O, Nor IF

Adv Exp Med Biol, 2011;696:461-9.
PMID: 21431586 DOI: 10.1007/978-1-4419-7046-6_46

Left ventricular motion estimation is very important for diagnosing cardiac abnormality. One of the popular techniques, optical flow technique, promises useful results for motion quantification. However, optical flow technique often failed to provide smooth vector field due to the complexity of cardiac motion and the presence of speckle noise. This chapter proposed a new filtering technique, called quasi-Gaussian discrete cosine transform (QGDCT)-based filter, to enhance the optical flow field for myocardial motion estimation. Even though Gaussian filter and DCT concept have been implemented in other previous researches, this filter introduces a different approach of Gaussian filter model based on high frequency properties of cosine function. The QGDCT is a customized quasi discrete Gaussian filter in which its coefficients are derived from a selected two-dimensional DCT. This filter was implemented before and after the computation of optical flow to reduce the speckle noise and to improve the flow field smoothness, respectively. The algorithm was first validated on synthetic echocardiography image that simulates a contracting myocardium motion. Subsequently, this method was also implemented on clinical echocardiography images. To evaluate the performance of the technique, several quantitative measurements such as magnitude error, angular error, and standard error of measurement are computed and analyzed. The final motion estimation results were in good agreement with the physician manual interpretation.

Matched MeSH terms: Ventricular Function, Left/physiology*
Myocardial ischaemic time and its relation with left ventricular ejection fraction after single valve replacement

Izham IN, Zamrin DM, Joanna OS, Ramzisham AR, Hairolfaizi H, Ishamuddin IM, et al.

Clin Ter, 2011;162(6):521-5.
PMID: 22262321

The effect of the duration of ischaemic myocardial time to left ventricular ejection fraction (LVEF) after valve replacement surgery has been attributed. This study aims to look at the correlation between myocardial ischaemic time and changes LVEF post valve replacement surgery up to 6 months period.

Matched MeSH terms: Ventricular Function, Left*
Review on CFD simulation in heart with dilated cardiomyopathy and myocardial infarction

Chan BT, Lim E, Chee KH, Abu Osman NA

Comput Biol Med, 2013 May;43(4):377-85.
PMID: 23428371 DOI: 10.1016/j.compbiomed.2013.01.013

The heart is a sophisticated functional organ that plays a crucial role in the blood circulatory system. Hemodynamics within the heart chamber can be indicative of exert cardiac health. Due to the limitations of current cardiac imaging modalities, computational fluid dynamics (CFD) have been widely used for the purposes of cardiac function assessment and heart disease diagnosis, as they provide detailed insights into the cardiac flow field. An understanding of ventricular hemodynamics and pathological severities can be gained through studies that employ the CFD method. In this research the hemodynamics of two common myocardial diseases, dilated cardiomyopathy (DCM) and myocardial infarction (MI) were investigated, during both the filling phase and the whole cardiac cycle, through a prescribed geometry and fluid structure interaction (FSI) approach. The results of the research indicated that early stage disease identification and the improvement of cardiac assisting devices and therapeutic procedures can be facilitated through the use of the CFD method.

Matched MeSH terms: Ventricular Function, Left/physiology
Motion corrected LV quantification based on 3D modelling for improved functional assessment in cardiac MRI

Liew YM, McLaughlin RA, Chan BT, Abdul Aziz YF, Chee KH, Ung NM, et al.

Phys Med Biol, 2015 Apr 7;60(7):2715-33.
PMID: 25768708 DOI: 10.1088/0031-9155/60/7/2715

Cine MRI is a clinical reference standard for the quantitative assessment of cardiac function, but reproducibility is confounded by motion artefacts. We explore the feasibility of a motion corrected 3D left ventricle (LV) quantification method, incorporating multislice image registration into the 3D model reconstruction, to improve reproducibility of 3D LV functional quantification. Multi-breath-hold short-axis and radial long-axis images were acquired from 10 patients and 10 healthy subjects. The proposed framework reduced misalignment between slices to subpixel accuracy (2.88 to 1.21 mm), and improved interstudy reproducibility for 5 important clinical functional measures, i.e. end-diastolic volume, end-systolic volume, ejection fraction, myocardial mass and 3D-sphericity index, as reflected in a reduction in the sample size required to detect statistically significant cardiac changes: a reduction of 21-66%. Our investigation on the optimum registration parameters, including both cardiac time frames and number of long-axis (LA) slices, suggested that a single time frame is adequate for motion correction whereas integrating more LA slices can improve registration and model reconstruction accuracy for improved functional quantification especially on datasets with severe motion artefacts.

Matched MeSH terms: Ventricular Function, Left*
Fulltext Extracorporeal shockwave myocardial therapy is efficacious in improving symptoms in patients with refractory angina pectoris--a multicenter study

Prasad M, Wan Ahmad WA, Sukmawan R, Magsombol EB, Cassar A, Vinshtok Y, et al.

Coron Artery Dis, 2015 May;26(3):194-200.
PMID: 25734606 DOI: 10.1097/MCA.0000000000000218

OBJECTIVE: Medically refractory angina remains a significant health concern despite major advances in revascularization techniques and emerging medical therapies. We aimed to determine the safety and efficacy of extracorporeal shockwave myocardial therapy (ESMT) in managing angina pectoris.
METHODS: A single-arm multicenter prospective study was designed aiming to determine the safety and efficacy of ESMT. Patients of functional Canadian Cardiovascular Society class II-IV, despite stable and optimal medical management, with documented myocardial segments with reversible ischemia and/or hibernation on the basis of echocardiography/single-photon emission computerized tomography (SPECT) were enrolled from 2010 to 2012. A total of 111 patients were enrolled, 33 from Indonesia, 21 from Malaysia, and 57 from Philippines. Patients underwent nine cycles of ESMT over 9 weeks. Patients were followed up for 3-6 months after ESMT treatment. During follow-up, patients were subjected to clinical evaluation, the Seattle Angina Questionnaire, assessment of nitrate intake, the 6-min walk test, echocardiography, and SPECT.
RESULTS: The mean age of the population was 62.9±10.9 years. The summed difference score on pharmacologically induced stress SPECT improved from 9.53±17.87 at baseline to 7.77±11.83 at follow-up (P=0.0086). Improvement in the total Seattle Angina Questionnaire score was seen in 83% of patients (P<0.0001). Sublingual nitroglycerin use significantly decreased (1.14±1.01 tablets per week at baseline to 0.52±0.68 tablets per week at follow-up; P=0.0215). There were no changes in left ventricular function on echocardiography (0.33±9.97, P=0.93). The Canadian Cardiovascular Society score improved in 74.1% of patients.
CONCLUSION: This multicenter prospective trial demonstrated that ESMT is both a safe and an efficacious means of managing medically refractory angina.

Matched MeSH terms: Ventricular Function, Left
Fulltext Predictors of diastolic dysfunction in rheumatoid arthritis

Sakthiswary R, Das S

Saudi Med J, 2015 May;36(5):525-9.
PMID: 25935171 DOI: 10.15537/smj.2015.5.10751

The main objective was to determine the predictors of diastolic dysfunction in rheumatoid arthritis (RA). Articles pertaining to diastolic dysfunction in RA were retrieved from Scopus, EBSCO, PubMed, Web of Science, and Cochrane Library databases. Keywords such as: diastolic, cardiac, left ventricular function, heart failure, rheumatoid arthritis, and cardiac failure were used. Studies, which examined factors, or predictors of diastolic dysfunction in RA, and those with echocardiographic evaluation of diastolic dysfunction, were included. A total of 8 studies met the eligibility criteria. Most studies (6 out of 7 studies) demonstrated a significant inverse relationship between the E (early)/A (late) ratio and disease duration. The pooled analysis using the random effects model revealed a significant but weak inverse relationship between the ratio of the E to A ventricular filling velocities (E/A) ratio and the disease duration (p less than 0.05, r=-0.385). There was a significant relationship between E/A ratio and disease duration in RA.

Study site: Hospital Kuala Lumpur (HKL)

Matched MeSH terms: Ventricular Function, Left
Fulltext Echocardiographic Findings Predict In-Hospital and 1-Year Mortality in Left-Sided Native Valve Staphylococcus aureus Endocarditis: Analysis From the International Collaboration on Endocarditis-Prospective Echo Cohort Study

Lauridsen TK, Park L, Tong SY, Selton-Suty C, Peterson G, Cecchi E, et al.

Circ Cardiovasc Imaging, 2015 Jul;8(7):e003397.
PMID: 26162783 DOI: 10.1161/CIRCIMAGING.114.003397

Staphylococcus aureus left-sided native valve infective endocarditis (LNVIE) has higher complication and mortality rates compared with endocarditis from other pathogens. Whether echocardiographic variables can predict prognosis in S aureus LNVIE is unknown.

Matched MeSH terms: Ventricular Function, Left
Anatomy and Physiology of Left Ventricular Suction Induced by Rotary Blood Pumps

Salamonsen RF, Lim E, Moloney J, Lovell NH, Rosenfeldt FL

Artif Organs, 2015 Aug;39(8):681-90.
PMID: 26146861 DOI: 10.1111/aor.12550

This study in five large greyhound dogs implanted with a VentrAssist left ventricular assist device focused on identification of the precise site and physiological changes induced by or underlying the complication of left ventricular suction. Pressure sensors were placed in left and right atria, proximal and distal left ventricle, and proximal aorta while dual perivascular and tubing ultrasonic flow meters measured blood flow in the aortic root and pump outlet cannula. When suction occurred, end-systolic pressure gradients between proximal and distal regions of the left ventricle on the order of 40-160 mm Hg indicated an occlusive process of variable intensity in the distal ventricle. A variable negative flow difference between end systole and end diastole (0.5-3.4 L/min) was observed. This was presumably mediated by variable apposition of the free and septal walls of the ventricle at the pump inlet cannula orifice which lasted approximately 100 ms. This apposition, by inducing an end-systolic flow deficit, terminated the suction process by relieving the imbalance between pump requirement and delivery from the right ventricle. Immediately preceding this event, however, unnaturally low end-systolic pressures occurred in the left atrium and proximal left ventricle which in four dogs lasted for 80-120 ms. In one dog, however, this collapse progressed to a new level and remained at approximately -5 mm Hg across four heart beats at which point suction was relieved by manual reduction in pump speed. Because these pressures were associated with a pulmonary capillary wedge pressure of -5 mm Hg as well, they indicate total collapse of the entire pulmonary venous system, left atrium, and left ventricle which persisted until pump flow requirement was relieved by reducing pump speed. We suggest that this collapse caused the whole vascular region from pulmonary capillaries to distal left ventricle to behave as a Starling resistance which further reduced right ventricular output thus contributing to a major reduction in pump flow. We contend that similar complications of manual speed control also occur in the human subject and remain a major unsolved problem in the clinical management of patients implanted with rotary blood pumps.

Matched MeSH terms: Ventricular Function, Left*
Effects of Statin Treatment on Inflammation and Cardiac Function in Heart Failure: An Adjusted Indirect Comparison Meta-Analysis of Randomized Trials

Bonsu KO, Reidpath DD, Kadirvelu A

Cardiovasc Ther, 2015 Dec;33(6):338-46.
PMID: 26280110 DOI: 10.1111/1755-5922.12150

Statins are known to prevent heart failure (HF). However, it is unclear whether statins as class or type (lipophilic or hydrophilic) improve outcomes of established HF.

Matched MeSH terms: Ventricular Function, Left/drug effects
Fulltext Preload-based starling-like control for rotary blood pumps: numerical comparison with pulsatility control and constant speed operation

Mansouri M, Salamonsen RF, Lim E, Akmeliawati R, Lovell NH

PLoS One, 2015;10(4):e0121413.
PMID: 25849979 DOI: 10.1371/journal.pone.0121413

In this study, we evaluate a preload-based Starling-like controller for implantable rotary blood pumps (IRBPs) using left ventricular end-diastolic pressure (PLVED) as the feedback variable. Simulations are conducted using a validated mathematical model. The controller emulates the response of the natural left ventricle (LV) to changes in PLVED. We report the performance of the preload-based Starling-like controller in comparison with our recently designed pulsatility controller and constant speed operation. In handling the transition from a baseline state to test states, which include vigorous exercise, blood loss and a major reduction in the LV contractility (LVC), the preload controller outperformed pulsatility control and constant speed operation in all three test scenarios. In exercise, preload-control achieved an increase of 54% in mean pump flow ([Formula: see text]) with minimum loading on the LV, while pulsatility control achieved only a 5% increase in flow and a decrease in mean pump speed. In a hemorrhage scenario, the preload control maintained the greatest safety margin against LV suction. PLVED for the preload controller was 4.9 mmHg, compared with 0.4 mmHg for the pulsatility controller and 0.2 mmHg for the constant speed mode. This was associated with an adequate mean arterial pressure (MAP) of 84 mmHg. In transition to low LVC, [Formula: see text] for preload control remained constant at 5.22 L/min with a PLVED of 8.0 mmHg. With regards to pulsatility control, [Formula: see text] fell to the nonviable level of 2.4 L/min with an associated PLVED of 16 mmHg and a MAP of 55 mmHg. Consequently, pulsatility control was deemed inferior to constant speed mode with a PLVED of 11 mmHg and a [Formula: see text] of 5.13 L/min in low LVC scenario. We conclude that pulsatility control imposes a danger to the patient in the severely reduced LVC scenario, which can be overcome by using a preload-based Starling-like control approach.

Matched MeSH terms: Ventricular Function, Left/physiology*
The MitraClip Asia-Pacific registry: Differences in outcomes between functional and degenerative mitral regurgitation

Tay E, Muda N, Yap J, Muller DW, Santoso T, Walters DL, et al.

Catheter Cardiovasc Interv, 2016 Jun;87(7):E275-81.
PMID: 26508564 DOI: 10.1002/ccd.26289

OBJECTIVES: The objective of this study is to describe and compare the use of the MitraClip therapy in mitral regurgitation (MR) patients with degenerative MR (DMR) and functional MR (FMR).
INTRODUCTION: Percutaneous edge-to-edge repair of severe MR using the MitraClip device is approved for use in the USA for high risk DMR while European guidelines include its use in FMR patients as well.
METHODS: The MitraClip in the Asia-Pacific Registry (MARS) is a multicenter retrospective registry, involving eight sites in five Asia-Pacific countries. Clinical and echocardiographic characteristics, procedural outcomes and 1-month outcomes [death and major adverse events (MAE)] were compared between FMR and DMR patients treated with the MitraClip.
RESULTS: A total of 163 patients were included from 2011 to 2014. The acute procedural success rates for FMR (95.5%, n = 84) and DMR (92%, n = 69) were similar (P = 0.515). 45% of FMR had ≥2 clips inserted compared to 60% of those with DMR (P = 0.064).The 30-day mortality rate for FMR and DMR was similar at 4.5% and 6.7% respectively (P = 0.555). The 30-day MAE rate was 9.2% for FMR and 14.7% for DMR (P = 0.281). Both FMR and DMR patients had significant improvements in the severity of MR and NYHA class after 30 days. There was a significantly greater reduction in left ventricular end-diastolic diameter (P = 0.002) and end systolic diameter (P = 0.017) in DMR than in FMR.
CONCLUSIONS: The MitraClip therapy is a safe and efficacious treatment option for both FMR and DMR. Although, there is a significantly greater reduction in LV volumes in DMR, patients in both groups report clinical benefit with improvement in functional class. © 2015 Wiley Periodicals, Inc.

Matched MeSH terms: Ventricular Function, Left
Echocardiographic agreement in the diagnostic evaluation for infective endocarditis

Lauridsen TK, Selton-Suty C, Tong S, Afonso L, Cecchi E, Park L, et al.

Int J Cardiovasc Imaging, 2016 Jul;32(7):1041-51.
PMID: 27100526 DOI: 10.1007/s10554-016-0873-5

Echocardiography is essential for the diagnosis and management of infective endocarditis (IE). However, the reproducibility for the echocardiographic assessment of variables relevant to IE is unknown. Objectives of this study were: (1) To define the reproducibility for IE echocardiographic variables and (2) to describe a methodology for assessing quality in an observational cohort containing site-interpreted data. IE reproducibility was assessed on a subset of echocardiograms from subjects enrolled in the International Collaboration on Endocarditis registry. Specific echocardiographic case report forms were used. Intra-observer agreement was assessed from six site readers on ten randomly selected echocardiograms. Inter-observer agreement between sites and an echocardiography core laboratory was assessed on a separate random sample of 110 echocardiograms. Agreement was determined using intraclass correlation (ICC), coverage probability (CP), and limits of agreement for continuous variables and kappa statistics (κweighted) and CP for categorical variables. Intra-observer agreement for LVEF was excellent [ICC = 0.93 ± 0.1 and all pairwise differences for LVEF (CP) were within 10 %]. For IE categorical echocardiographic variables, intra-observer agreement was best for aortic abscess (κweighted = 1.0, CP = 1.0 for all readers). Highest inter-observer agreement for IE categorical echocardiographic variables was obtained for vegetation location (κweighted = 0.95; 95 % CI 0.92-0.99) and lowest agreement was found for vegetation mobility (κweighted = 0.69; 95 % CI 0.62-0.86). Moderate to excellent intra- and inter-observer agreement is observed for echocardiographic variables in the diagnostic assessment of IE. A pragmatic approach for determining echocardiographic data reproducibility in a large, multicentre, site interpreted observational cohort is feasible.

Matched MeSH terms: Ventricular Function, Left
Fulltext Association of testosterone, inflammation with the severity of first acute ST-elevation myocardial infarction

Wickramatilake CM, Mohideen MR, Pathirana C

Indian Heart J, 2017 02 12;69(2):291.
PMID: 28460787 DOI: 10.1016/j.ihj.2017.02.002
Matched MeSH terms: Ventricular Function, Left/physiology*
Multinational and multiethnic variations in health-related quality of life in patients with chronic heart failure

Luo N, Teng TK, Tay WT, Anand IS, Kraus WE, Liew HB, et al.

Am Heart J, 2017 Sep;191:75-81.
PMID: 28888273 DOI: 10.1016/j.ahj.2017.06.016

BACKGROUND: Assessing health-related quality of life (HRQoL) in patients with heart failure (HF) is an important goal of clinical care and HF research. We sought to investigate ethnic differences in perceived HRQoL and its association with mortality among patients with HF and left ventricular ejection fraction ≤35%, controlling for demographic characteristics and HF severity.
METHODS AND RESULTS: We compared 5697 chronic HF patients of Indian (26%), white (23%), Chinese (17%), Japanese/Koreans (12%), black (12%), and Malay (10%) ethnicities from the HF-ACTION and ASIAN-HF multinational studies using the Kansas City Cardiomyopathy Questionnaire (KCCQ; range 0-100; higher scores reflect better health status). KCCQ scores were lowest in Malay (58±22) and Chinese (60±23), intermediate in black (64±21) and Indian (65±23), and highest in white (67±20) and Japanese or Korean patients (67±22) after adjusting for age, sex, educational status, HF severity, and risk factors. Self-efficacy, which measures confidence in the ability to manage symptoms, was lower in all Asian ethnicities (especially Japanese/Koreans [60±26], Malay [66±23], and Chinese [64±28]) compared to black (80±21) and white (82±19) patients, even after multivariable adjustment (P

Matched MeSH terms: Ventricular Function, Left/physiology
Left ventricular flow propagation velocity measurement: Is it cast in stone?

Chan BT, Yeoh HK, Liew YM, Aziz YFA, Sridhar GS, Hamilton-Craig C, et al.

Med Biol Eng Comput, 2017 Oct;55(10):1883-1893.
PMID: 28321684 DOI: 10.1007/s11517-017-1639-5

This study aims to investigate the measurement of left ventricular flow propagation velocity, V p, using phase contrast magnetic resonance imaging and to assess the discrepancies resulting from inflow jet direction and individual left ventricular size. Three V p measuring techniques, namely non-adaptive (NA), adaptive positions (AP) and adaptive vectors (AV) method, were suggested and compared. We performed the comparison on nine healthy volunteers and nine post-infarct patients at four measurement positions, respectively, at one-third, one-half, two-thirds and the conventional 4 cm distances from the mitral valve leaflet into the left ventricle. We found that the V p measurement was affected by both the inflow jet direction and measurement positions. Both NA and AP methods overestimated V p, especially in dilated left ventricles, while the AV method showed the strongest correlation with the isovolumic relaxation myocardial strain rate (r = 0.53, p left ventricular sizes and inflow jet directions.

Matched MeSH terms: Ventricular Function, Left/physiology*
Fulltext Preload-based Starling-like control of rotary blood pumps: An in-vitro evaluation

Mansouri M, Gregory SD, Salamonsen RF, Lovell NH, Stevens MC, Pauls JP, et al.

PLoS One, 2017;12(2):e0172393.
PMID: 28212401 DOI: 10.1371/journal.pone.0172393

Due to a shortage of donor hearts, rotary left ventricular assist devices (LVADs) are used to provide mechanical circulatory support. To address the preload insensitivity of the constant speed controller (CSC) used in conventional LVADs, we developed a preload-based Starling-like controller (SLC). The SLC emulates the Starling law of the heart to maintain mean pump flow ([Formula: see text]) with respect to mean left ventricular end diastolic pressure (PLVEDm) as the feedback signal. The SLC and CSC were compared using a mock circulation loop to assess their capacity to increase cardiac output during mild exercise while avoiding ventricular suction (marked by a negative PLVEDm) and maintaining circulatory stability during blood loss and severe reductions in left ventricular contractility (LVC). The root mean squared hemodynamic deviation (RMSHD) metric was used to assess the clinical acceptability of each controller based on pre-defined hemodynamic limits. We also compared the in-silico results from our previously published paper with our in-vitro outcomes. In the exercise simulation, the SLC increased [Formula: see text] by 37%, compared to only 17% with the CSC. During blood loss, the SLC maintained a better safety margin against left ventricular suction with PLVEDm of 2.7 mmHg compared to -0.1 mmHg for CSC. A transition to reduced LVC resulted in decreased mean arterial pressure (MAP) and [Formula: see text] with CSC, whilst the SLC maintained MAP and [Formula: see text]. The results were associated with a much lower RMSHD value with SLC (70.3%) compared to CSC (225.5%), demonstrating improved capacity of the SLC to compensate for the varying cardiac demand during profound circulatory changes. In-vitro and in-silico results demonstrated similar trends to the simulated changes in patient state however the magnitude of hemodynamic changes were different, thus justifying the progression to in-vitro evaluation.

Matched MeSH terms: Ventricular Function, Left/physiology*
Primary Arterial Switch Operation for Late Referral of Transposition of the Great Arteries with Intact Ventricular Septum in the Current Era: Do We Still Need a Rapid Two-Stage Operation?

Ota N, Sivalingam S, Pau KK, Hew CC, Dillon J, Latiff HA, et al.

World J Pediatr Congenit Heart Surg, 2018 01;9(1):74-78.
PMID: 29310554 DOI: 10.1177/2150135117743225

OBJECTIVE: We introduced primary arterial switch operation for the patient with transposition of great arteries and intact ventricular septum (TGA-IVS) who had more than 3.5 mm of posterior left ventricle (LV) wall thickness.
METHODS: Between January 2013 and June 2015, a total of 116 patients underwent arterial switch operation. Of the 116 patients, 26 with TGA-IVS underwent primary arterial switch operation at more than 30 days of age.
RESULTS: The age and body weight (mean ± SD) at the operation were 120.4 ± 93.8 days and 4.1 ±1.0 kg, respectively. There was no hospital mortality. The thickness of posterior LV wall (preoperation vs postoperation; mm) was 4.04 ± 0.71 versus 5.90 ± 1.3; P < .0001; interval: 11.8 ± 6.5 days. The left atrial pressure (mm Hg; postoperative day 0 vs 3) was 20.0 ± 3.2 versus 10.0 ± 2.0; P < .0001; and the maximum blood lactate level (mmol/dL) was 4.7 ± 1.4 versus 1.4 ± 0.3; P < .0001, which showed significant improvement in the postoperative course. All cases had delayed sternal closure. The patients who belonged to the thin LV posterior wall group (<4 mm [preoperative echo]: n = 13) had significantly longer ventilation time (days; 10.6 ± 4.8 vs 4.8 ± 1.7, P = .0039), and the intensive care unit stay (days) was 14 ± 9.2 versus 7.5 ± 3.5; P = .025, compared with thick LV wall group (≥4.0 mm: n = 13).
CONCLUSIONS: The children older than 30 days with TGA-IVS can benefit from primary arterial switch operation with acceptable results under our indication. However, we need further investigation for LV function.

Matched MeSH terms: Ventricular Function, Left
Fulltext Isoflurane's Effect on Intraoperative Systolic Left Ventricular Performance in Cardiac Valve Surgery Patients

Kim JD, Son I, Kwon WK, Sung TY, Sidik H, Kim K, et al.

J Korean Med Sci, 2018 01 22;33(4):e28.
PMID: 29318795 DOI: 10.3346/jkms.2018.33.e28

BACKGROUND: Isoflurane, a common anesthetic for cardiac surgery, reduced myocardial contractility in many experimental studies, few studies have determined isoflurane's direct impact on the left ventricular (LV) contractile function during cardiac surgery. We determined whether isoflurane dose-dependently reduces the peak systolic velocity of the lateral mitral annulus in tissue Doppler imaging (S') in patients undergoing cardiac surgery.
METHODS: During isoflurane-supplemented remifentanil-based anesthesia for patients undergoing cardiac surgery with preoperative LV ejection fraction greater than 50% (n = 20), we analyzed the changes of S' at each isoflurane dose increment (1.0, 1.5, and 2.0 minimum alveolar concentration [MAC]: T1, T2, and T3, respectively) with a fixed remifentanil dosage (1.0 μg/min/kg) by using transesophageal echocardiography.
RESULTS: Mean S' values (95% confidence interval [CI]) at T1, T2, and T3 were 10.5 (8.8-12.2), 9.5 (8.3-10.8), and 8.4 (7.3-9.5) cm/s, respectively (P < 0.001 in multivariate analysis of variance test). Their mean differences at T1 vs. T2, T2 vs. T3, and T1 vs. T3 were -1.0 (-1.6, -0.3), -1.1 (-1.7, -0.6), and -2.1 (-3.1, -1.1) cm/s, respectively. Phenylephrine infusion rates were significantly increased (0.26, 0.22, and 0.47 μg/kg/min at T1, T2, and T3, respectively, P < 0.001).
CONCLUSION: Isoflurane increments (1.0-2.0 MAC) dose-dependently reduced LV systolic long-axis performance during cardiac surgeries with a preserved preoperative systolic function.

Matched MeSH terms: Ventricular Function, Left/drug effects; Ventricular Function, Left/physiology*

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