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The Journal of Cardiovascular Surgery Feb 2022Mitral valve repair with papillary muscle approximation (MVr-PMA) for severe secondary mitral regurgitation (MR) decreases MR recurrence compared with MVr alone. This...
BACKGROUND
Mitral valve repair with papillary muscle approximation (MVr-PMA) for severe secondary mitral regurgitation (MR) decreases MR recurrence compared with MVr alone. This study assessed the effects of MVr-PMA on left ventricular (LV) remodeling and shape, systolic function and strain mechanics.
METHODS
Forty-eight patients who underwent MVr-PMA for severe secondary MR and had follow-up echocardiograms available for review were identified. Student's t-test, linear regression modeling, and receiver-operating characteristic curves were used in the statistical analyses.
RESULTS
Median follow-up time was 14.9 months. MVr-PMA was associated with significant LV reverse remodeling with a smaller LV end-diastolic diameter, Systolic Sphericity Index, and interpapillary muscle distance at follow-up. Nine patients (18.8%) experienced moderate recurrent MR. When compared to recurrent MR patients at follow-up, those with durable MVr-PMA had a greater LV ejection fraction (32.8 vs. 22.0%, P=0.03), a smaller end-diastolic diameter (59.6 vs. 67.3 mm, P=0.03), Systolic Sphericity Index (0.35 vs. 0.47, P=0.03), and end-systolic interpapillary muscle distance (16.3 vs. 21.1 mm, P=0.03). A durable MVr-PMA also resulted in stable global longitudinal strain when compared with pre-operative values, while the recurrent MR group experienced a further decline (no recurrent MR: -8.4 vs. -7.5%; recurrent MR: -8.2 vs. -5.4%; P<0.05). A pre-operative LV end-diastolic diameter ≥ 64 mm was a discriminative predictor of MR recurrence (sensitivity=100%, specificity=51%, AUC=0.756, P=0.02).
CONCLUSIONS
A durable MVr-PMA confers improved LV geometry and function, and stable LV mechanics. The extent of baseline LV remodeling identifies patients at risk for recurrent MR.
Topics: Biomechanical Phenomena; Echocardiography; Humans; Mitral Valve; Mitral Valve Annuloplasty; Mitral Valve Insufficiency; Papillary Muscles; Recovery of Function; Recurrence; Severity of Illness Index; Systole; Time Factors; Treatment Outcome; Ventricular Function, Left; Ventricular Remodeling
PubMed: 34057163
DOI: 10.23736/S0021-9509.21.11843-9 -
ASAIO Journal (American Society For... Aug 2021Papillary muscle rupture (PMR) or chordae tendinae rupture (CTR) is a rare but lethal complication after ST elevation myocardial infarction (STEMI). Due to the rarity of...
Papillary muscle rupture (PMR) or chordae tendinae rupture (CTR) is a rare but lethal complication after ST elevation myocardial infarction (STEMI). Due to the rarity of this condition, there are limited studies defining its epidemiology and outcomes. This is a retrospective study from Nationwide Inpatient Sample database from 2002 to 2014 of patients with STEMI and PMR/CTR. Outcomes of interest were incidence of in-hospital mortality, cardiogenic shock (CS), utilization of mechanical circulatory support (MCS) devices and mitral valve procedures (MVPs) among patients with and without rupture. We also performed simulation using the cardiovascular model to better understand the hemodynamics of severe mitral regurgitation and effects of different medications and device therapy. We identified 1,888 patients with STEMI complicated with PMR/CTR. Most of the patients were >65 years of age (65.3%), male (63.6%), and white (82.3%). They had significantly higher incidence of CS, cardiac arrest, and utilization of MCS devices. In-hospital mortality was higher in patients with rupture (41% vs. 7.40%, p < 0.001) which remained unchanged over the study period. Hospitalization cost and length of stay was also higher in them. MVP and revascularization led to better survival rates (27.9% vs. 60.6%, adjusted OR: 0.14; 95% CI: 0.10-0.19; p < 0.001). Despite significant advancement in the revascularization strategy, PMR/CTR after STEMI continues to portend poor prognosis with high inpatient mortality. Cardiogenic shock is a common presentation and is associated with significantly inpatient mortality. Future studies are needed determine the best strategies to improve outcomes in patients with STEMI with PMR/CTR and CS.
Topics: Aged; Female; Hospital Mortality; Humans; Male; Papillary Muscles; Retrospective Studies; ST Elevation Myocardial Infarction; Shock, Cardiogenic
PubMed: 33093383
DOI: 10.1097/MAT.0000000000001299 -
Journal of Cardiovascular... Dec 2021Myxomatous mitral valve prolapse (MVP) and mitral-annular disjunction (Barlow disease) are at-risk for ventricular arrhythmias (VA). Fibrosis involving the papillary...
BACKGROUND
Myxomatous mitral valve prolapse (MVP) and mitral-annular disjunction (Barlow disease) are at-risk for ventricular arrhythmias (VA). Fibrosis involving the papillary muscles and/or the infero-basal left ventricular (LV) wall was reported at autopsy in sudden cardiac death (SCD) patients with MVP.
OBJECTIVES
We investigated the electrophysiological substrate subtending VA in MVP patients with Barlow disease phenotype.
METHODS
Twenty-three patients with VA were enrolled, including five with syncope and four with a history of SCD. Unipolar (Uni < 8.3 mV) and bipolar (Bi < 1.5 mV) low-voltage areas were analyzed with electro-anatomical mapping (EAM), and VA inducibility was evaluated with programmed ventricular stimulation (PES). Electrophysiological parameters were correlated with VA patterns, electrocardiogram (ECG) inferior negative T wave (nTW), and late gadolinium enhancement (LGE) assessed by cardiac magnetic resonance.
RESULTS
Premature ventricular complex (PVC) burden was 12 061.9 ± 12 994.6/24 h with a papillary-muscle type (PM-PVC) in 18 patients (68%). Twelve-lead ECG showed nTW in 12 patients (43.5%). A large Uni less than 8.3 mV area (62.4 ± 45.5 cm ) was detected in the basal infero-lateral LV region in 12 (73%) patients, and in the papillary muscles (2.2 ± 2.9 cm ) in 5 (30%) of 15 patients undergoing EAM. A concomitant Bi less than 1.5 mV area (5.0 ± 1.0 cm ) was identified in two patients. A history of SCD, and the presence of nTW, and LGE were associated with a greater Uni less than 8.3 mV extension: (32.8 ± 3.1 cm vs. 9.2 ± 8.7 cm ), nTW (20.1 ± 11.0 vs. 4.1 ± 3.8 cm ), and LGE (19.2 ± 11.7 cm vs. 1.0 ± 2.0 cm , p = .013), respectively. All patients with PM-PVC had a Uni less than 8.3 mV area. Sustained VA (ventricular tachycardia 2 and VF 2) were induced by PES only in four patients (one with resuscitated SCD).
CONCLUSIONS
Low unipolar low voltage areas can be identified with EAM in the basal inferolateral LV region and in the papillary muscles as a potential electrophysiological substrate for VA and SCD in patients with MVP and Barlow disease phenotype.
Topics: Contrast Media; Gadolinium; Humans; Mitral Valve Prolapse; Papillary Muscles; Ventricular Premature Complexes
PubMed: 34664762
DOI: 10.1111/jce.15270 -
Journal of Cardiovascular Translational... Jun 2023Ventricular tachycardia associated with papillary muscle (PM) is often refractory to standard radiofrequency ablation (RFA). The needle-tipped ablation catheter (NT-AC)...
Ventricular tachycardia associated with papillary muscle (PM) is often refractory to standard radiofrequency ablation (RFA). The needle-tipped ablation catheter (NT-AC) has been used to treat deep intramyocardial substrates, but its use for PM has not been characterized. Using an ex vivo experimental platform, both 3 mm and 6 mm NT-AC created larger ablation lesion volumes and depths than open-irrigated ablation catheter did (OI-AC; e.g., 57.12 ± 9.70mm and 2.42 ± 0.22 mm, respectively; p < 0.01 for all comparisons). Longer NT-AC extension (6 mm) resulted in greater ablation lesion volumes and maximum depths (e.g., 333.14 ± 29.13mm and 6.46 ± 0.29 mm, respectively, compared to the shorter 3 mm NT-AC extension, 143.33 ± 12.77mm, and 4.46 ± 0.14 mm; both p < 0.001). There were no steam pops. In conclusion, for PM ablation, the NT-AC was able to achieve ablation lesions that were larger and deeper than with conventional OI-AC. Ablation of PM may be another application for needle-tip ablation. Further studies are warranted to establish long-term safety and efficacy in human studies.
Topics: Humans; Papillary Muscles; Therapeutic Irrigation; Equipment Design; Catheters; Catheter Ablation
PubMed: 36264437
DOI: 10.1007/s12265-022-10331-z -
The Annals of Thoracic Surgery Jan 2022Surgical restoration of subvalvular geometry is very important to prevent recurrence of ischemic/functional mitral regurgitation. We evaluated an approach to the radical...
Surgical restoration of subvalvular geometry is very important to prevent recurrence of ischemic/functional mitral regurgitation. We evaluated an approach to the radical repair of left ventricular (LV) remodeling for three different cases with responsible coronary lesions. Leaflet tethering was corrected by tugging of the papillary-ventricular complex, which consists of the base of papillary muscles and posterior LV wall. The main lesion of the postinfarction scar was concomitantly excluded. Restoration of LV remodeling diminished mitral regurgitation with minimal leaflet tethering and improved systolic LV function. This technique may be an aggressive and encouraged approach for patients with ischemic/functional mitral regurgitation.
Topics: Cardiac Surgical Procedures; Heart Ventricles; Humans; Mitral Valve Insufficiency; Myocardial Ischemia; Papillary Muscles
PubMed: 33891917
DOI: 10.1016/j.athoracsur.2021.03.095 -
Journal of the Mechanical Behavior of... Nov 2020The mitral valve (MV) apparatus is a complex mechanical structure including annulus, valve leaflets, papillary muscles (PMs) and connected chordae tendineae. Chordae...
The mitral valve (MV) apparatus is a complex mechanical structure including annulus, valve leaflets, papillary muscles (PMs) and connected chordae tendineae. Chordae anchor to the papillary muscles to help the valve open and close properly during one cardiac cycle. It is of paramount importance to understand the functional, mechanical, and microstructural properties of mitral valve chordae and connecting PMs. In particular, little is known about the biomechanical properties of the anterior and posterior papillary muscle and corresponding chords. In this work, we performed uniaxial and biaxial tensile tests on the anterolateral (APM) and posteromedial papillary muscle (PPM), and their respective corresponding chordae tendineae, chordae and chordae, in porcine hearts. Histology was carried out to link the microstructure and macro-mechanical behavior of the chordae and PMs. Our results demonstrate that chordae are less in number, but significantly longer and stiffer than chordae. These different biomechanical properties may be partially explained by the higher collagen core ratio and larger collagen fibril density of chordae No significant mechanical or microstructural differences were observed along the circumferential and longitudinal directions of APM and PPM samples. Data measured on chordae and PMs were further fitted with the Ogden and reduced Holzapfel - Ogden strain energy functions, respectively. This study presents the first comparative anatomical, mechanical, and structural dataset of porcine mitral valve chordae and related PMs. Results indicate that a PM based classification of chordae will need to be considered in the analysis of the MV function or planning a surgical treatment, which will also help developing more precise computational models of MV.
Topics: Animals; Chordae Tendineae; Collagen; Mitral Valve; Mitral Valve Insufficiency; Papillary Muscles; Swine
PubMed: 32835989
DOI: 10.1016/j.jmbbm.2020.104011 -
JACC. Cardiovascular Imaging Sep 2019This study sought to define interpapillary muscle dyssynchrony as a major contributing factor in functional mitral regurgitation (FMR) and prove the reversibility of FMR... (Observational Study)
Observational Study
OBJECTIVES
This study sought to define interpapillary muscle dyssynchrony as a major contributing factor in functional mitral regurgitation (FMR) and prove the reversibility of FMR by interpapillary muscle resynchronization.
BACKGROUND
Mechanistic features of FMR include papillary muscle displacement due to left ventricular remodeling. Intraventricular conduction delay might further augment this condition by introducing interpapillary muscle dyssynchrony.
METHODS
We enrolled 269 chronic heart failure with reduced ejection fraction patients with conduction delay and comprehensively assessed dyssynchrony by complementary echocardiographic techniques covering the entire spectrum of dyssynchrony.
RESULTS
Patients with severe FMR had markedly increased interpapillary longitudinal dyssynchrony (160 ms [interquartile range (IQR): 120 to 200 ms]) compared with those with moderate (70 ms [IQR: 40 to 110 ms]), no, or mild FMR (60 ms [IQR: 30 to 100 ms]; p < 0.001). Increased interpapillary muscle dyssynchrony was correlated with regurgitant volume (r = 0.50; p < 0.001) and vena contracta width (r = 0.49; p < 0.001). Restoration of longitudinal papillary muscle synchronicity by cardiac resynchronization therapy was correlated with FMR regression, as reflected by the reduction in regurgitant volume (r = 0.46; p < 0.001) and vena contracta width (r = 0.58; p < 0.001). Conversely, the improvement of FMR was associated with improved interpapillary radial (p = 0.006) and longitudinal (p < 0.001) dyssynchrony. The improvement of dyssynchrony-mediated FMR signified a better prognosis compared with no improvement in FMR during the 8-year follow-up period even after comprehensive adjustment by a bootstrap-selected confounder model (adjusted hazard ratio: 0.41; 95% confidence interval: 0.18 to 0.91; p = 0.028). The results remained virtually unchanged after adjustment for left bundle branch block.
CONCLUSIONS
Intraventricular dyssynchrony introduces unequal contraction by papillary muscle bearing walls, which has an adverse effect on FMR. Cardiac resynchronization therapy can effectively restore interpapillary balance and thus create a less tented leaflet configuration, resulting in a clinically meaningful reduction of FMR. The restoration of papillary muscle synchronicity in dyssynchrony-mediated FMR translates into a significantly better prognosis.
Topics: Aged; Cardiac Resynchronization Therapy; Chronic Disease; Female; Heart Failure; Humans; Male; Middle Aged; Mitral Valve; Mitral Valve Insufficiency; Myocardial Contraction; Papillary Muscles; Recovery of Function; Stroke Volume; Treatment Outcome; Ventricular Dysfunction, Left; Ventricular Function, Left; Ventricular Remodeling
PubMed: 30121264
DOI: 10.1016/j.jcmg.2018.06.013 -
JACC. Clinical Electrophysiology Oct 2020
Topics: Humans; Catheter Ablation; Electrophysiology; Papillary Muscles; Ventricular Premature Complexes
PubMed: 33121668
DOI: 10.1016/j.jacep.2020.08.005 -
Interdisciplinary Cardiovascular and... Jun 2023Ring annuloplasty represents the standard surgical treatment, but offers suboptimal results in patients with severe functional tricuspid regurgitation. Addition of...
OBJECTIVES
Ring annuloplasty represents the standard surgical treatment, but offers suboptimal results in patients with severe functional tricuspid regurgitation. Addition of papillary muscles (PMs) approximation may improve clinical outcomes.
METHODS
Eight healthy adult male sheep (56 ± 4 kg) underwent cardiopulmonary bypass and implantation of sonomicrometry crystals on the tricuspid annulus, PM tips and right ventricular (RV) free wall. Papillary muscles approximation sutures were anchored between anterior-posterior and anterior-septal PMs and their loose ends externalized through RV free wall to epicardial tourniquets. After weaning from cardiopulmonary bypass, acute right heart failure and tricuspid regurgitation were induced, and subsequent sequential anterior-posterior and anterior-septal PM approximations were performed. Echocardiographic, haemodynamic and sonomicrometry data were collected.
RESULTS
Tricuspid regurgitation at baseline in eight sheep was none or trace in 3 and mild in 5, and after induction of acute right heart failure increased significantly to moderate in 5, moderately severe in 1 and severe in 2 (P = 0.011). RV pressure increased from 31 [28; 43] to 51 [47; 55] mmHg (P = 0.012). Anterior-posterior PM approximation decreased regurgitation grade to none or trace in 1, mild in 4 and moderate in 3 (P = 0.016) and reduced PM area from 208 [160; 241] to 108 [48; 181] mm2 (P = 0.008), and anterior-posterior PM distance from 18 [16; 20] to 10 [7; 13] mm (P = 0.037). Anterior-septal approximation also significantly reduced PM area but had no effect on regurgitation grade.
CONCLUSIONS
Anterior-posterior but not anterior-septal PM approximation alleviated acute ovine tricuspid regurgitation. Selective PM approximation may offer better control of tricuspid regurgitation.
PubMed: 37348860
DOI: 10.1093/icvts/ivad098