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Morphological variations of papillary muscles in the mitral valve complex in human cadaveric hearts.Singapore Medical Journal Jan 2013Papillary muscle rupture and dysfunction can lead to complications of prolapsed mitral valve and mitral regurgitation. Multiple operative procedures of the papillary...
INTRODUCTION
Papillary muscle rupture and dysfunction can lead to complications of prolapsed mitral valve and mitral regurgitation. Multiple operative procedures of the papillary muscles, such as resection, repositioning and realignment, are carried out to restore normal physiological function. Therefore, it is important to know both the variations and the normal anatomy of papillary muscles.
METHODS
This study was carried out on 116 human cadaveric hearts. The left ventricles were opened along the left border in order to view the papillary muscles. The number, shape, position and pattern of the papillary muscles were observed.
RESULTS
In this series, the papillary muscles were mostly found in groups instead of in twos, as is described in standard textbooks. Four different shapes of papillary muscles were identified - conical, broad-apexed, pyramidal and fan-shaped. We also discovered various patterns of papillary muscles.
CONCLUSION
No two mitral valve complexes have the same architectural arrangement. Each case seems to be unique. Therefore, it is important for scientists worldwide to study the variations in the mitral valve complex in order to ascertain the reason behind each specific architectural arrangement. This will enable cardiothoracic surgeons to tailor the surgical procedures according to the individual papillary muscle pattern.
Topics: Adult; Anatomy; Cadaver; Chordae Tendineae; Heart; Humans; Middle Aged; Mitral Valve; Mitral Valve Insufficiency; Models, Anatomic; Papillary Muscles; Thoracic Surgery
PubMed: 23338917
DOI: 10.11622/smedj.2013011 -
Circulation Journal : Official Journal... Nov 2022
Topics: Humans; Papillary Muscles; Heart Rupture, Post-Infarction; Myocardial Infarction; Mitral Valve Insufficiency
PubMed: 36047168
DOI: 10.1253/circj.CJ-22-0391 -
Journal of Electrocardiology 2011Vectorcardiographic QRS loops illustrate the electrical activation of the left ventricle (LV) in 3-dimensional space; however, the individual variability in these loops...
BACKGROUND
Vectorcardiographic QRS loops illustrate the electrical activation of the left ventricle (LV) in 3-dimensional space; however, the individual variability in these loops is not well understood. The left bundle-branch fan distributes the initial activation to the LV and has been shown to distribute its fascicles between the LV papillary muscles. Computer models of LV activation using papillary muscle as the initial electrical activation points accurately predict QRS duration and frontal plane axis.
METHODS
Twelve healthy adults received standard 12-lead electrocardiograms and 1.5-T cardiac magnetic resonance imaging. A software developed by ECG-TECH Corp (Huntington Station, NY) generated 3-dimensional QRS vector loops for each subject. Short- and long-axis papillary muscle positions were measured for each subject using cardiac magnetic resonance images. A theoretical plane equidistant from the endocardial origins of each papillary muscle was constructed. Vectors perpendicular to the QRS vector loop and the theoretical plane termed the plane identifier were used for comparison. Spearman rank correlation was used to compare the azimuth and elevation of the plane identifiers of the QRS vector loop and the theoretical plane.
RESULTS
No correlation was found between the azimuth or elevation of the theoretical plane and the QRS vector loops with Spearman rank correlation coefficients of ρ = 0.11 (P = .71) and ρ = 0.22 (P = .49), respectively. Subgroup analysis by QRS vector loop morphology (planar vs nonplanar, narrow vs wide) also demonstrated no correlation.
CONCLUSIONS
Modeling the activation of the LV based on papillary muscle position alone may be overly simplistic. Better understanding of what other factors contribute to individual variation in LV activation will help develop a more useful theoretical model.
Topics: Adult; Female; Heart Conduction System; Humans; Magnetic Resonance Imaging; Male; Papillary Muscles; Predictive Value of Tests; Software; Statistics, Nonparametric; Vectorcardiography
PubMed: 21872004
DOI: 10.1016/j.jelectrocard.2011.06.010 -
Annals of Thoracic and Cardiovascular... 2024Systolic anterior motion of the anterior mitral leaflet can persist after ventricular septal myectomy for obstructive hypertrophic cardiomyopathy, resulting in residual...
Systolic anterior motion of the anterior mitral leaflet can persist after ventricular septal myectomy for obstructive hypertrophic cardiomyopathy, resulting in residual pressure gradients and mitral regurgitation. However, additional procedures for systolic anterior motion involving mitral valve leaflet suturing and resection may lead to future valve disease. Therefore, we adopted posterior papillary muscle suspension, a subvalvular procedure for functional mitral regurgitation, to treat systolic anterior motion without directly intervening in the mitral valve leaflets. Papillary muscle suspension toward the posterior mitral annulus moved the papillary muscles away from the interventricular septum and successfully eliminated the systolic anterior motion and midventricular pressure gradient. In terms of avoiding direct mitral interventions, this procedure is a viable option for systolic anterior motion, especially in cases of very mild mitral regurgitation.
Topics: Humans; Papillary Muscles; Mitral Valve Insufficiency; Echocardiography; Treatment Outcome; Cardiomyopathy, Hypertrophic
PubMed: 38296519
DOI: 10.5761/atcs.nm.23-00176 -
JACC. Clinical Electrophysiology Oct 2020This study sought to address whether technological innovations such as contact force sensing (CFS) can improve acute and long-term ablation outcomes of left ventricular...
OBJECTIVES
This study sought to address whether technological innovations such as contact force sensing (CFS) can improve acute and long-term ablation outcomes of left ventricular papillary muscle (LV PAP) ventricular arrhythmias (VAs).
BACKGROUND
Catheter ablation of LV PAP VAs has been less efficacious than another focal VAs. It remains unclear whether technological innovations such as CFS can improve acute and long-term ablation outcomes of LV PAP VA.
METHODS
From January 2015 to December 2019, a total of 137 patients underwent LV PAP VA ablation. VA site of origin (SOO) was identified using activation and pace-mapping guided by intracardiac echocardiography. Radiofrequency energy (20 to 50 W for 60 to 90 s) was delivered by irrigated catheter with or without CFS. We defined acute success as complete suppression of targeted VA ≥30 min post ablation and clinical success as ≥80% VA burden reduction at outpatient follow-up.
RESULTS
VA manifested as premature ventricular complexes in 98 (71%), nonsustained ventricular tachycardia in 18 (13%), sustained ventricular tachycardia in 12 (9%) and premature ventricular complexes induced ventricular fibrillation in 9 (7%). VA SOO was anterolateral PAP in 51 (37%), posteromedial PAP in 73 (53%), and both PAPs in 13 (10%). VAs were targeted using CFS in 97 (71%) and non-CFS in 40 (29%). After a single procedure, acute success was achieved in 130 (95%) and clinical success was achieved in 112 (82%); neither was impacted by VA SOO and/or CFS. Complications occurred in 5 patients (3.6%).
CONCLUSION
Independent of CFS technology, intracardiac echocardiography-guided catheter ablation is highly efficacious and may be considered as first-line therapy in the management of LV PAP VA.
Topics: Catheter Ablation; Heart Ventricles; Humans; Papillary Muscles; Tachycardia, Ventricular; Ventricular Premature Complexes
PubMed: 33121667
DOI: 10.1016/j.jacep.2020.06.026 -
British Journal of Pharmacology Sep 19771 The potency and selectivity of 5-(1-hydroxy-2-isopropylamino)butyl-8-hydroxy carbostyril hydrochloride hemihydrate (OPC-2009), a new beta(2)-adrenoceptor stimulant,...
Assessment of the selectivity of OPC-2009, a new beta2-adrenoceptor stimulatn, by the use of the blood-perfused trachea in situ and of the isolated blood-perfused papillary muscle of the dog.
1 The potency and selectivity of 5-(1-hydroxy-2-isopropylamino)butyl-8-hydroxy carbostyril hydrochloride hemihydrate (OPC-2009), a new beta(2)-adrenoceptor stimulant, was compared with those of isoprenaline, trimetoquinol and salbutamol by the use of blood-perfused tracheal preparations in situ and of blood-perfused papillary muscle preparations of the dog. All drugs were injected intra-arterially.2 All the four drugs decreased tracheal intraluminal pressure (tracheal relaxation) and increased tracheal blood flow in a dose-dependent manner. The four drugs produced a dose-dependent increase in developed tension of papillary muscles. In both preparations the duration of action of isoprenaline and salbutamol was short, whereas that of OPC-2009 and trimetoquinol was long. These effects were antagonized by propranolol.3 Dose-response curves to the four drugs for tracheal relaxation were almost parallel. OPC-2009 was 2.4 times more potent, and trimetoquinol and salbutamol were 2.2 and 6.2 times less potent than isoprenaline in causing tracheal relaxation.4 Dose-response curves to the four drugs for tracheal vasodilatation were also parallel. OPC-2009, trimetoquinol and salbutamol were 3.9, 6.7 and 23 times less potent than isoprenaline.5 Slopes of the dose-response curves to the four drugs for increased developed tension were not parallel; that of OPC-2009 was the least steep, whereas that of isoprenaline was the steepest. Trimetoquinol, salbutamol and OPC-2009 were about 18, 570 and 2400 times less potent than isoprenaline.6 Selectivity calculated from relative potencies indicate that OPC-2009 was about 6000 times, salbutamol about 92 times and trimetoquinol about 8.2 times more selective than isoprenaline for tracheal smooth muscle as compared to ventricular muscle.7 The high potency and selectivity of OPC-2009 for tracheal smooth muscle and its long duration of action suggest its potential usefulness for treatment of bronchial asthma.8 The present results are also compatible with the concept that beta(1)-adrenoceptors in cardiac muscle and beta(2)-adrenoceptors in tracheal and vascular smooth muscle can be distinguished. Furthermore, the results revealed that the beta-adrenoceptors mediating tracheal relaxation and vasodilatation may also be different.
Topics: Adrenergic beta-Agonists; Albuterol; Animals; Dogs; Female; Heart; Hydroxyquinolines; In Vitro Techniques; Isoproterenol; Male; Muscle Contraction; Papillary Muscles; Perfusion; Regional Blood Flow; Trachea; Tretoquinol
PubMed: 21014
DOI: 10.1111/j.1476-5381.1977.tb09734.x -
Journal of Visualized Experiments : JoVE Sep 2015Papillary muscle isolated from adult mouse hearts can be used to study cardiac contractility during different physiological/pathological conditions. The contractile...
Papillary muscle isolated from adult mouse hearts can be used to study cardiac contractility during different physiological/pathological conditions. The contractile characteristics can be evaluated independently of external influences such as vascular tonus or neurohumoral status. It depicts a scientific approach between single cell measurements with isolated cardiac myocytes and in vivo studies like echocardiography. Thus, papillary muscle preparations serve as an excellent model to study cardiac physiology/pathophysiology and can be used for investigations like the modulation by pharmacological agents or the exploration of transgenic animal models. Here, we describe a method of isolating the murine left anterior papillary muscle to investigate cardiac contractility in an organ bath setup. In contrast to a muscle strip preparation isolated from the ventricular wall, the papillary muscle can be prepared in toto without damaging the muscle tissue severely. The organ bath setup consists of several temperature-controlled, gassed and electrode-equipped organ bath chambers. The isolated papillary muscle is fixed in the organ bath chamber and electrically stimulated. The evoked twitch force is recorded using a pressure transducer and parameters such as twitch force amplitude and twitch kinetics are analyzed. Different experimental protocols can be performed to investigate the calcium- and frequency-dependent contractility as well as dose-response curves of contractile agents such as catecholamines or other pharmaceuticals. Additionally, pathologic conditions like acute ischemia can be simulated.
Topics: Adrenergic beta-Agonists; Animals; Calcium; Electric Stimulation; Isolated Heart Preparation; Mice; Myocardial Contraction; Myocytes, Cardiac; Papillary Muscles; Signal Transduction
PubMed: 26436250
DOI: 10.3791/53076 -
JACC. Cardiovascular Imaging Dec 2009The objective of this study was to test the hypothesis that patients with primum atrioventricular septal defect (AVSD) have an imbalance in the positions of the left...
OBJECTIVES
The objective of this study was to test the hypothesis that patients with primum atrioventricular septal defect (AVSD) have an imbalance in the positions of the left ventricular papillary muscles compared with healthy subjects, and that this anatomic imbalance correlates with left deviation of the QRS axis.
BACKGROUND
The function and contraction pattern of the heart is best predicted when cardiac anatomy is considered together with its electrical activation sequence. Understanding the electroanatomic relationships is essential for discovering the developmental relationships between the conduction system and heart structures. Left deviation of the QRS axis is typically present in patients with primum AVSD. However, the pathophysiology of this phenomenon is not understood.
METHODS
Thirty-five patients with primum AVSD and 35 healthy subjects were included in the study. Echocardiographic images were used to determine the papillary muscle positions. A 12-lead electrocardiogram was used to determine the QRS axis in the frontal plane in both patients and healthy subjects.
RESULTS
An imbalance between papillary muscle positions in primum AVSD patients was defined as the position of the anterior papillary muscle closer to the septum and/or the position of the posterior papillary muscle further from the septum compared with the position of the papillary muscles in healthy subjects. In primum AVSD patients compared with control subjects, there was significant imbalance in the positions of the papillary muscles (p = 0.0007). The imbalance of papillary muscles correlated with deviation of the QRS (r = 0.5, p = 0.0019).
CONCLUSIONS
Abnormality in the position of the papillary muscles changes continuously with the abnormality of the QRS axis. Understanding the electroanatomic relationships provides important insight into developmental relationships between the conduction system and the trabecular structures in primum AVSD patients. These results may provide insights in understanding the continuity of primum AVSD abnormality, in estimating the best surgical approach, and predicting the prognosis of primum AVSD patients.
Topics: Adolescent; Adult; Case-Control Studies; Child; Child, Preschool; Electrocardiography; Female; Heart Conduction System; Heart Septal Defects, Atrial; Humans; Infant; Male; Papillary Muscles; Time Factors; Ultrasonography; Young Adult
PubMed: 20083068
DOI: 10.1016/j.jcmg.2009.08.009 -
Journal of Cardiology Oct 2008
Topics: Cardiomyopathies; Humans; Mitral Valve Insufficiency; Myocardial Ischemia; Papillary Muscles
PubMed: 18922393
DOI: 10.1016/j.jjcc.2008.07.012 -
The Journal of Thoracic and... Dec 2010Papillary muscle displacement relative to mitral annulus is pivotal in chronic functional ischemic mitral regurgitation. Analysis of 3-dimensional papillary muscle...
OBJECTIVE
Papillary muscle displacement relative to mitral annulus is pivotal in chronic functional ischemic mitral regurgitation. Analysis of 3-dimensional papillary muscle displacement has relied on invasive measurement. In this study, we used noninvasive clinically applicable 3-dimensional morphology cardiac magnetic resonance imaging to define papillary muscle position in a 3-dimensional matrix.
METHODS
Fifty pigs (approximately 50 kg) were subjected to posterolateral myocardial infarction and tachycardiac stress. Fourteen animals survived 6 weeks: 10 acquired chronic functional ischemic mitral regurgitation at least grade II and 4 did not. Animals were examined by 3-dimensional morphology cardiac magnetic resonance imaging, and dedicated software enabled assessment of anterior and posterior papillary muscle positions relative to anterior and posterior trigones and posterior mitral annulus. Animals with functional ischemic mitral regurgitation were compared with those without and with 10 healthy controls.
RESULTS
Relative to controls, animals with functional ischemic mitral regurgitation at end systole had significantly higher displacements of the posterior papillary muscle from anterior and posterior trigones in lateral and posterior directions, and of anterior papillary muscle from anterior and posterior trigones in apical direction. Relative to animals without functional ischemic mitral regurgitation, there was significantly higher posterior papillary muscle displacement from posterior trigone in lateral direction. Interpapillary muscle distance was the strongest predictor of regurgitant volume (r(2) = 0.85, P < .001).
CONCLUSIONS
Three-dimensional morphology cardiac magnetic resonance imaging enabled detailed analysis of local left ventricular remodeling effects causing functional ischemic mitral regurgitation.
Topics: Animals; Coronary Angiography; Disease Models, Animal; Echocardiography; Female; Hemodynamics; Imaging, Three-Dimensional; Linear Models; Magnetic Resonance Imaging; Mitral Valve Insufficiency; Papillary Muscles; Swine
PubMed: 20347098
DOI: 10.1016/j.jtcvs.2009.12.042