Dataset Information

Cardiac remodelling and haemodynamic characteristics in primary mitral valve regurgitation.

ABSTRACT: Objective:To assess the association between cardiac morphology and function assessed with cardiac MRI (CMRI) and haemodynamics at rest and during exercise in patients with primary mitral regurgitation (MR). Methods:In an observational study, subjects with significant primary MR (N = 46) with effective regurgitant orifice ? 0.30?cm2 and left ventricular (LV) ejection fraction > 60% were examined with right heart catheterisation during rest and exercise and CMRI at rest. End-diastolic pressure volume relationship (EDPVR) was assessed using a single beat method using pulmonary capillary wedge pressure (PCWP) and end-diastolic volume. Patients were divided according to normal PCWP at rest (> 12?mm Hg) and with exercise (> 28?mm Hg). Results: Resting regurgitant volume correlated positively with resting PCWP, (r = 0.42, p = 0.002). However, with exercise no association between PCWP and regurgitant volume was seen (r = 0.09, p = 0.55). At rest left atrial (LA) maximal, minimal and volume index at atrial contraction correlated positively with PCWP (r = 0.60; r = 0.55; r = 0.58, all p < 0.001); in contrast none of these correlated with exercise PCWP (all p > 0.2). EDPVR in patients with high PCWP at rest was shifted towards higher volumes for the same pressures. The opposite was seen for patients with high PCWP during exercise where estimated volumes were smaller for the same pressure than patients with normal exercise PCWP. Conclusion:In patients with significant MR the degree of regurgitation and LA dilatation is associated with resting PCWP. However, with exercise this association disappears. Estimation of EDPVR suggests lower LV compliance in patients where PCWP is increased with exercise. Clinical trial registration:URL: https://clinicaltrials.gov/ct2/show/NCT02961647?term=HEMI&rank=1. ID: NCT02961647.

SUBMITTER: Bakkestrom R

PROVIDER: S-EPMC6307562 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Cardiac remodelling and haemodynamic characteristics in primary mitral valve regurgitation.

Bakkestrøm Rine R Banke Ann A Pecini Redi R Irmukhamedov Akhmadjon A Nielsen Søren Kristian SK Andersen Mads J MJ Borlaug Barry A BA Moller Jacob Eifer JE

Open heart 20181216 2

<h4>Objective</h4>To assess the association between cardiac morphology and function assessed with cardiac MRI (CMRI) and haemodynamics at rest and during exercise in patients with primary mitral regurgitation (MR).<h4>Methods</h4>In an observational study, subjects with significant primary MR (N = 46) with effective regurgitant orifice ≥ 0.30 cm<sup>2</sup> and left ventricular (LV) ejection fraction > 60% were examined with right heart catheterisation during rest and exercise and CMRI at rest. ...[more]

PMID: 30613416

Similar Datasets

Project description:OBJECTIVES:The Cardiothoracic Surgical Trials Network recently reported no difference in the primary end point of left ventricular end-systolic volume index at 1 year postsurgery in patients randomized to repair (n = 126) or replacement (n = 125) for severe ischemic mitral regurgitation. However, patients undergoing repair experienced significantly more recurrent mitral regurgitation than patients undergoing replacement (32.6% vs 2.3%). We examined whether baseline echocardiographic and clinical characteristics could identify those who will develop moderate/severe recurrent mitral regurgitation or die. METHODS:Our analysis includes 116 patients who were randomized to and received mitral valve repair. Logistic regression was used to estimate a model-based probability of recurrence or death from baseline factors. Receiver operating characteristic curves were constructed from these estimated probabilities to determine classification cut-points maximizing accuracy of prediction based on sensitivity and specificity. RESULTS:Of the 116 patients, 6 received a replacement before leaving the operating room; all other patients had mild or less mitral regurgitation on intraoperative echocardiogram after repair. During the 2-year follow-up period, 76 patients developed moderate/severe mitral regurgitation or died (53 mitral regurgitation recurrences, 13 mitral regurgitation recurrences and death, and 10 deaths). The mechanism for recurrent mitral regurgitation was largely mitral valve leaflet tethering. Our model (including age, body mass index, sex, race, effective regurgitant orifice area, basal aneurysm/dyskinesis, New York Heart Association class, history of coronary artery bypass grafting, percutaneous coronary intervention, or ventricular arrhythmias) yielded an area under the receiver operating characteristic curve of 0.82. CONCLUSIONS:The model demonstrated good discrimination in identifying patients who will survive 2 years without recurrent mitral regurgitation after mitral valve repair. Although our results require validation, they offer a clinically relevant risk score for selection of surgical candidates for this procedure.

Project description:BackgroundMild physiologic mitral regurgitation (MR) is common in normal individuals. Patients with primary MR due to mitral valve prolapse (MVP) may also exhibit less than moderate MR. We sought to determine whether MVP patients with less than moderate MR displayed early cardiac chamber remodeling or factors related to early remodeling and whether early remodeling predicted MR progression.MethodsConsecutive MVP patients with less than moderate MR by proximal isovelocity surface area-derived effective regurgitant orifice < 20 mm2 and regurgitant volume < 30 mL, were matched for age and sex with non-MVP patients (controls) having less than moderate MR. Patients with moderate or greater dysfunctional left- or right-sided valves and left ventricular ejection fraction < 50% were excluded. We evaluated left ventricle (LV) and left atrium (LA) remodeling parameters (LV end-diastolic and end-systolic indexed diameters, LA volume-index, and LV mass-index) as well as determinants of remodeling. The last available transthoracic echocardiography was reviewed to identify progression to moderate-severe MR or more.ResultsA total of 253 MVP patients with less than moderate MR were matched to 344 controls (P for age and sex, ≥.18) with less than moderate MR. Patients with MVP (mean effective regurgitant orifice and regurgitant volume, 12 ± 4 mm2 and 18 ± 6 mL, respectively) had more premature ventricular contractions (PVCs), larger LV and LA remodeling parameters, and more mild-to-moderate MR (all P < .0001). Multivariate linear regression models showed that larger LV remodeling parameters were independently associated with MVP and female sex but not MR severity (all P < .0001). The LA volume index was independently associated with MVP, age, and E/e' (all P < .0001). The LV mass index was associated with MVP, age, and hypertension (all P ≤ .002). Presence of PVCs was associated with LV end-systolic diameter ≥ 40 mm and indexed ≥ 22 mm2 (P = .005). Among 323 (54%) patients having subsequent transthoracic echocardiography, 17 patients (all MVP) progressed to moderate-severe MR or more at a median of 4.3 (interquartile range, 1.7-6.4) years. Isolated posterior leaflet prolapse was the single factor associated with MR progression (adjusted hazard ratio, 2.70; 95% CI, 0.99-7.34; P = .048) after adjustment for MR severity. At a median of 5.9 (interquartile range, 4.6-7.2) years of follow-up, female sex and MVP (vs controls) were protective factors for mortality.ConclusionsPatients with less than moderate MR due to MVP exhibit early LV and LA remodeling, which does not predict MR progression or mortality. Left ventricle remodeling is associated with MVP, female sex, and presence of PVCs. Early chamber remodeling associated with MVP may be the phenotypical expression of a genetically mediated process and is at least partially related to PVCs.

Project description:Rationale: Ischemic mitral regurgitation (IMR) is frequently observed following myocardial infarction (MI) and is associated with higher mortality and poor clinical prognosis if left untreated. Accumulating evidence suggests that mitral valve (MV) leaflets actively remodel post-MI, yet the cellular mechanisms underlying these responses and how this affects tissue function remain largely unknown. Objective: We sought to elucidate MV remodeling post-MI at the tissue, cellular, and transcriptomic levels. Methods and Results: The mechanical behavior of ovine MV leaflets pre-MI and 8 weeks post-MI reveal a significant decrease in radial direction extensibility, which essentially eliminated the mechanical anisotropy typically observed in healthy MVs. Quantitative histology and ultrastructural assessment by transmission electron microscopy revealed altered leaflet composition and architecture at 8 weeks post-MI. Assessment of the MV interstitial cell (MVIC) nuclear aspect ratio, a metric of cellular deformation, revealed that MVICs were on average rounder following MI. RNA sequencing (RNA-seq) indicated that YAP-induced genes were elevated at 4 weeks post-MI and genes related to extracellular matrix organization were some of the most downregulated in sheep with IMR compared to sheep without IMR at 4 weeks post-MI. Additionally, RNA-seq revealed the possible recruitment of immune cells in this remodeling process due to the drastic elevation of CXCL9 and CLEC10A. Conclusions: This multiscale assessment revealed significant mechanical and microstructural changes due to MI. RNA-seq provided a baseline for global gene expression changes in response to MI with and without IMR and suggests YAP-induced mechanotransduction, altered expression of ECM-related genes, and recruitment of immune cells as mechanisms contributing to altered MV biomechanics post-MI. Conclusions: This multiscale assessment revealed significant mechanical and microstructural changes due to MI. RNA-seq provided a baseline for global gene expression changes in response to MI with and without IMR and suggests YAP-induced mechanotransduction, altered expression of ECM-related genes, and recruitment of immune cells as mechanisms contributing to altered MV biomechanics post-MI.

Dataset Information

Cardiac remodelling and haemodynamic characteristics in primary mitral valve regurgitation.

Publications

Cardiac remodelling and haemodynamic characteristics in primary mitral valve regurgitation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets