Displaying all 16 publications

Abstract:
Sort:
  1. Chuah SH, Md Sari NA, Tan LK, Chiam YK, Chan BT, Abdul Aziz YF, et al.
    J Cardiovasc Transl Res, 2023 Oct;16(5):1110-1122.
    PMID: 37022611 DOI: 10.1007/s12265-023-10375-9
    Left ventricular adaptations can be a complex process under the influence of aortic stenosis (AS) and comorbidities. This study proposed and assessed the feasibility of using a motion-corrected personalized 3D + time LV modeling technique to evaluate the adaptive and maladaptive LV response to aid treatment decision-making. A total of 22 AS patients were analyzed and compared against 10 healthy subjects. The 3D + time analysis showed a highly distinct and personalized pattern of remodeling in individual AS patients which is associated with comorbidities and fibrosis. Patients with AS alone showed better wall thickening and synchrony than those comorbid with hypertension. Ischemic heart disease in AS caused impaired wall thickening and synchrony and systolic function. Apart from showing significant correlations to echocardiography and clinical MRI measurements (r: 0.70-0.95; p 
    Matched MeSH terms: Ventricular Function, Left/physiology
  2. 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*
  3. 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*
  4. Zhou H, Zainal H, Puntmann VO
    Aging (Albany NY), 2019 03 25;11(6):1609-1610.
    PMID: 30908271 DOI: 10.18632/aging.101890
    Matched MeSH terms: Ventricular Function, Left/physiology*
  5. Rordorf R, Scazzuso F, Chun KRJ, Khelae SK, Kueffer FJ, Braegelmann KM, et al.
    J Am Heart Assoc, 2021 Dec 21;10(24):e021323.
    PMID: 34889108 DOI: 10.1161/JAHA.121.021323
    Background Heart failure (HF) and atrial fibrillation (AF) often coexist; yet, outcomes of ablation in patients with AF and concomitant HF are limited. This analysis assessed outcomes of cryoablation in patients with AF and HF. Methods and Results The Cryo AF Global Registry is a prospective, multicenter registry of patients with AF who were treated with cryoballoon ablation according to routine practice at 56 sites in 26 countries. Patients with baseline New York Heart Association class I to III (HF cohort) were compared with patients without HF. Freedom from atrial arrhythmia recurrence ≥30 seconds, safety, and health care utilization over 12-month follow-up were analyzed. A total of 1303 patients (318 HF) were included. Patients with HF commonly had preserved left ventricular ejection fraction (81.6%), were more often women (45.6% versus 33.6%) with persistent AF (25.8% versus 14.3%), and had a larger left atrial diameter (4.4±0.9 versus 4.0±0.7 cm). Serious procedure-related complications occurred in 4.1% of patients with HF and 2.6% of patients without HF (P=0.188). Freedom from atrial arrhythmia recurrence was not different between cohorts with either paroxysmal AF (84.2% [95% CI, 78.6-88.4] versus 86.8% [95% CI, 84.2-89.0]) or persistent AF (69.6% [95% CI, 58.1-78.5] versus 71.8% [95% CI, 63.2-78.7]) (P=0.319). After ablation, a reduction in AF-related symptoms and antiarrhythmic drug use was observed in both cohorts (HF and no-HF), and freedom from repeat ablation was not different between cohorts. Persistent AF and HF predicted a post-ablation cardiovascular rehospitalization (P=0.032 and P=0.001, respectively). Conclusions Cryoablation to treat patients with AF is similarly effective at 12 months in patients with and without HF. Registration URL: https://www.clinicaltrials.gov; Unique Identifier: NCT02752737.
    Matched MeSH terms: Ventricular Function, Left/physiology
  6. 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*
  7. 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*
  8. Solomon SD, Ostrominski JW, Vaduganathan M, Claggett B, Jhund PS, Desai AS, et al.
    Eur J Heart Fail, 2024 Jun;26(6):1334-1346.
    PMID: 38733212 DOI: 10.1002/ejhf.3266
    AIMS: To describe the baseline characteristics of participants in the FINEARTS-HF trial, contextualized with prior trials including patients with heart failure (HF) with mildly reduced and preserved ejection fraction (HFmrEF/HFpEF). The FINEARTS-HF trial is comparing the effects of the non-steroidal mineralocorticoid receptor antagonist finerenone with placebo in reducing cardiovascular death and total worsening HF events in patients with HFmrEF/HFpEF.

    METHODS AND RESULTS: Patients with symptomatic HF, left ventricular ejection fraction (LVEF) ≥40%, estimated glomerular filtration rate ≥ 25 ml/min/1.73 m2, elevated natriuretic peptide levels and evidence of structural heart disease were enrolled and randomized to finerenone titrated to a maximum of 40 mg once daily or matching placebo. We validly randomized 6001 patients to finerenone or placebo (mean age 72 ± 10 years, 46% women). The majority were New York Heart Association functional class II (69%). The baseline mean LVEF was 53 ± 8% (range 34-84%); 36% of participants had a LVEF <50% and 64% had a LVEF ≥50%. The median N-terminal pro-B-type natriuretic peptide (NT-proBNP) was 1041 (interquartile range 449-1946) pg/ml. A total of 1219 (20%) patients were enrolled during or within 7 days of a worsening HF event, and 3247 (54%) patients were enrolled within 3 months of a worsening HF event. Compared with prior large-scale HFmrEF/HFpEF trials, FINEARTS-HF participants were more likely to have recent (within 6 months) HF hospitalization and greater symptoms and functional limitations. Further, concomitant medications included a larger percentage of sodium-glucose cotransporter 2 inhibitors and angiotensin receptor-neprilysin inhibitors than previous trials.

    CONCLUSIONS: FINEARTS-HF has enrolled a broad range of high-risk patients with HFmrEF and HFpEF. The trial will determine the safety and efficacy of finerenone in this population.

    Matched MeSH terms: Ventricular Function, Left/physiology
  9. 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*
  10. 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
  11. Aslannif R, Suraya K, Koh HB, Tey YS, Tan KL, Tham CH, et al.
    Med J Malaysia, 2019 12;74(6):521-526.
    PMID: 31929479
    INTRODUCTION: Apical Hypertrophic Cardiomyopathy (Apical HCM) is an uncommon variant of hypertrophic cardiomyopathy, but it is relatively more common in Asian countries. This is a retrospective, non-randomised, single centre study of patients with Apical HCM focusing on their diastolic dysfunction grading, echocardiographic parameters and electrocardiograms (ECG).

    METHODS: All Apical HCM patients coming for clinic visits at the Institut Jantung Negara from September 2017 to September 2018 were included. We assessed their echocardiography images, grade their diastolic function and reviewed their ECG on presentation.

    RESULTS: Fifty patient were included, 82% (n=41) were males and 18% (n=9) females. The diastolic function grading of 37 (74%) patients were able to be determined using the updated 2016 American Society of Echocardiography (ASE) diastolic guidelines. Fifty percent (n=25) had the typical ace-ofspades shape left ventricle (LV) appearance in diastole and 12% (n=6) had apical pouch. All patients had T inversion in the anterior leads of their ECG, and only 52% (n=26) fulfilled the ECG left ventricular hypertrophy (LVH) criteria. Majority of our patients presented with symptoms of chest pain (52%, n=26) and dyspnoea (42%, n=21).

    CONCLUSION: The updated 2016 ASE guideline makes it easier to evaluate LV diastolic function in most patients with Apical HCM. It also helps in elucidating the aetiology of dyspnoea, based on left atrial pressure. Clinicians should have a high index of suspicion for Apical HCM when faced with deep T inversion on ECG, in addition to a thick LV apex with an aceof- spades appearance during diastole.

    Matched MeSH terms: Ventricular Function, Left/physiology*
  12. Haranal M, Leong MC, Muniandy SR, Khalid KF, Sivalingam S
    Ann Thorac Surg, 2020 10;110(4):e327-e329.
    PMID: 32224240 DOI: 10.1016/j.athoracsur.2020.02.039
    Conjoined twins are rare congenital malformations known to be associated with cardiac abnormalities. Management of transposition of the great arteries with an intact ventricular septum in this subgroup of patients is challenging, especially in the presence of multiple comorbidities. Prevention of left ventricular involution until the patient is stable for an arterial switch operation is a real challenge. We report a case of early ductal stenting to keep the left ventricle well trained in a separated conjoined twin who eventually underwent an arterial switch operation.
    Matched MeSH terms: Ventricular Function, Left/physiology*
  13. Chia YC, Kieneker LM, van Hassel G, Binnenmars SH, Nolte IM, van Zanden JJ, et al.
    J Am Heart Assoc, 2021 06;10(11):e018549.
    PMID: 33998283 DOI: 10.1161/JAHA.120.018549
    Background The cause of heart failure with preserved ejection fraction (HFpEF) is poorly understood, and specific therapies are lacking. Previous studies suggested that inflammation plays a role in the development of HFpEF. Herein, we aimed to investigate in community-dwelling individuals whether a higher plasma interleukin 6 (IL-6) level is associated with an increased risk of developing new-onset heart failure (HF) over time, and specifically HFpEF. Methods and Results We performed a case-cohort study based on the PREVEND (Prevention of Renal and Vascular End-Stage Disease) study, a prospective general population-based cohort study. We included 961 participants, comprising 200 participants who developed HF and a random group of 761 controls. HF with reduced ejection fraction or HFpEF was defined on the basis of the left ventricular ejection fraction of ≤40% or >40%, respectively. In Cox proportional hazard regression analyses, IL-6 levels were statistically significantly associated with the development of HF (hazard ratio [HR], 1.28; 95% CI, 1.02-1.61; P=0.03) after adjustment for key risk factors. Specifically, IL-6 levels were significantly associated with the development of HFpEF (HR, 1.59; 95% CI, 1.16-2.19; P=0.004), whereas the association with HF with reduced ejection fraction was nonsignificant (HR, 1.05; 95% CI, 0.75-1.47; P=0.77). In sensitivity analyses, defining HFpEF as left ventricular ejection fraction ≥50%, IL-6 levels were also significantly associated with the development of HFpEF (HR, 1.47; 95% CI, 1.04-2.06; P=0.03) after adjustment for key risk factors. Conclusions IL-6 is associated with new-onset HFpEF in community-dwelling individuals, independent of potential confounders. Our findings warrant further research to investigate whether IL-6 might be a novel treatment target to prevent HFpEF.
    Matched MeSH terms: Ventricular Function, Left/physiology*
  14. 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/physiology*
  15. Leong MC, Ahmed Alhassan AA, Sivalingam S, Alwi M
    Ann Thorac Surg, 2019 09;108(3):813-819.
    PMID: 30998905 DOI: 10.1016/j.athoracsur.2019.03.045
    BACKGROUND: Ductal stenting is performed to retrain involuted left ventricles (LVs) in patients with d-transposition of the great arteries and intact ventricular septum (TGA-IVS). However, its efficacy is largely unknown. This study aimed to determine the safety and efficacy of ductal stenting in retraining of the involuted LV in patients with TGA-IVS.

    METHODS: This was a single-center, retrospective study. Echocardiographic assessment of the LV geometry, mass, and free wall thickness was performed before stenting and before the arterial switch operation. Patients then underwent the arterial switch operation, and the postoperative outcomes were reviewed.

    RESULTS: There were 11 consecutive patients (male, 81.8%; mean age at stenting, 43.11 ± 18.19 days) with TGA-IVS with involuted LV who underwent LV retraining by ductal stenting from July 2013 to December 2017. Retraining by ductus stenting failed in 4 patients (36.3%). Two patients required pulmonary artery banding, and another 2 had an LV mass index of less than 35 g/m2. Patients in the successful group had improved LV mass index from 45.14 ± 17.91 to 81.86 ± 33.11g/m2 (p = 0.023) compared with 34.50 ± 10.47 to 20.50 ± 9.88 g/m2 (p = 0.169) and improved LV geometry after ductal stenting. The failed group was associated with an increased need for extracorporeal support (14.5% vs 50%, p = 0.012). An atrial septal defect-to-interatrial septum length ratio of more than 0.38 was associated with failed LV retraining.

    CONCLUSIONS: Ductal stenting is an effective method to retrain the involuted LV in TGA-IVS. A large atrial septal defect (atrial septal defect-to-interatrial septum length ratio >0.38) was associated with poor response to LV retraining.

    Matched MeSH terms: Ventricular Function, Left/physiology*
  16. 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
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links