Anterolateral Papillary Muscle Research Articles

Comparision of Papillary Muscle Deformation Parameters in Patients with Hypertrophic Cardiomyopathy and Hypertension

PP-190 The aim of the present study was to analyze anterolateral papillary muscle longitudinal strain (ALPM-St), posteromedial papillary muscle longitudinal strain (PMPM-St), anterolateral papillary muscle time to peak longitudinal strain (ALPM-time), posteromedial papillary muscle time to peak

In Vitro Images of a Double Orifice Mitral Valve in a Reanimated Human Heart

Using Visible Heart® methodologies [1] the heart from a 45 year old male (BMI 30.4, pre-op BP 145/70, HR 107, regular rhythm and normal heart tones), deemed not viable for transplant to a recipient patient, was explanted to an isolated heart apparatus. Briefly, this methodology utilizes a clear Krebs-Henseleit buffer to provide nutrients and oxygen to the heart and allow for native ex-vivo functionality while providing the opportunity to visualize the internal anatomy with endoscopes. Upon reanimation LV and LA pressures were 95/12mmHg and 13/15mmHg respectively during sinus rhythm. The patient’s heart presented with no signs of any other congenital pathology and a pre-operative ultrasound indicated a 65% LV ejection fraction, normal chamber dimensions and trivial mitral regurgitation. The double orifice mitral valve can best be defined as an incomplete bridge, situated toward the superior commissure of the valve and supported by the superolateral (anterolateral) papillary muscle. Shown here is a series of four screenshots of the valve in both systole (Figure 1 A&B) and diastole (Figure 1 C&D) from the left atrium (Figure 1 A&C) and the left ventricle (Figure 1 B&D). These images clearly show the fibrous connection between the mural (posteroinferior) and aortic (anterosuperior) leaflets in the central region. Interestingly, the chronic presence of the fibrous bridge in this patient has had seemingly negligible effect on overall cardiac performance. Functional video footage of the valve can be accessed via the link provided (An accompanying video for this article can be viewed on the Internet at http://ats.ctsnetjournals.org/content/volNUMBER/issueNUMBER/images/data/PAGE/DC1/FILENAME). Figure 1

Ischemic rupture of the anterolateral papillary muscle

We describe the case of a 59-year-old man who presented with chest pain and ST-segment elevation in the inferior leads, R>S in V1 and ST depression in the anterior leads due to proximal occlusion of the first obtuse marginal. Primary coronary angioplasty and stenting of this artery were performed. Twelve hours later the patient became hemodynamically unstable and severe mitral regurgitation due to rupture of one of the heads of the anterolateral papillary muscle was diagnosed. Emergency surgery was performed (papillary muscle head reimplantation, mitral annuloplasty with a rigid ring, tricuspid annuloplasty and coronary artery bypass grafting). On surgical inspection, it was observed that the detached muscle head had become trapped in the left ventricle by a secondary cord attached to the other head.This case is unusual in presenting two uncommon features of ischemic papillary muscle: rupture of the anterolateral muscle in myocardial infarction involving the inferoposterior walls, and the fact that the ruptured muscle head did not prolapse because it had become trapped in the left ventricle by secondary cord attachment.

Ischemic rupture of the anterolateral papillary muscle

We describe the case of a 59-year-old man who presented with chest pain and ST-segment elevation in the inferior leads, R>S in V1 and ST depression in the anterior leads due to proximal occlusion of the first obtuse marginal. Primary coronary angioplasty and stenting of this artery were performed. Twelve hours later the patient became hemodynamically unstable and severe mitral regurgitation due to rupture of one of the heads of the anterolateral papillary muscle was diagnosed. Emergency surgery was performed (papillary muscle head reimplantation, mitral annuloplasty with a rigid ring, tricuspid annuloplasty and coronary artery bypass grafting). On surgical inspection, it was observed that the detached muscle head had become trapped in the left ventricle by a secondary cord attached to the other head.This case is unusual in presenting two uncommon features of ischemic papillary muscle: rupture of the anterolateral muscle in myocardial infarction involving the inferoposterior walls, and the fact that the ruptured muscle head did not prolapse because it had become trapped in the left ventricle by secondary cord attachment.

The saddle shape of the mitral valve: More than just a shape

The knowledge about mitral valve (MV) has tremendously increased from the days when Andreas Vesalius suggested the picturesque term “mitral” to describe the left atrioventricular valve owing to its resemblance to a plan view of the bishop’s mitre. In its open state, the MV leaflets extend like a funnel from its base at the atrioventricular junction to the free margins. Tendinous chords attach the MV leaflets to two closely arranged anterolateral and posteromedial papillary muscle. The MV leaflets, the annulus, the atrial and ventricular wall surrounding the annulus, the tendinous chords, the papillary muscles, and the myocardium surrounding the papillary muscle attachment constitute the MV complex/apparatus. For the prevention of the back flow during systole, precisely timed interaction of all the anatomical components of the MV complex is essential. Alterations in the structure and function of any of these elements can lead to MV dysfunction. [1] The MV annulus is a concept and not an anatomically well-defined structure. The anterior one-third of the MV annulus that houses the anterior mitral leaflet (AML) is fibrous and well defined. Fibroelastic tissue extends posteriorly from the extremes of the anterior fibrous partial ring and forms the posterior two-thirds of the MV annulus; this part of the annulus tends to be “weak” and lacks a well-formed fibrous cord. The posterior mitral leaflet (PML) is attached to this part of the MV annulus. This is the area affected in “annular dilatation” and is often involved in calcification of the annulus.The MV is non-planar and obliquely located in the heart, and the annulus is saddle shaped. It is not known how the MV annulus acquires non-planar and saddle shape. Also, it is not known how this saddle shape is maintained. The finite element analyses consistently Access this article online

Severe Mitral Regurgitation due to Traumatic Anterolateral Papillary Muscle Rupture: A Case Report

A 29-year-old man was admitted for abrupt dyspnea and hemoptysis. An echocardiogram revealed severe mitral regurgitation due to papillary muscle rupture for which an emergency mitral valve replacement operation was performed 4 days after admission. Herein, we report our experience with this case along with a review of the literature.

Left ventricular dyssynchrony is associated with recurrence of ischemic mitral regurgitation after restrictive annuloplasty

BackgroundIn our study, we investigated the impact of papillary muscle systolic dyssynchrony (DYS-PAP) obtained by 2D speckle-tracking echocardiography (2D-STE) in the prediction of recurrent ischemic mitral regurgitation (MR) after restrictive annuloplasty. MethodsThe study population consisted of 524 consecutive patients who survived coronary artery bypass grafting (CABG) and restrictive annuloplasty, performed between 2001 and 2010 at 3 different Institutions and who met inclusion criteria. The assessment of DYS-PAP was performed preoperatively and at follow-up (median 45.3months [IQR 26–67]) by 2D-STE in the apical four-chamber view for the anterolateral papillary muscle (ALPM) and apical long-axis view for the posteromedial papillary muscle (PMPM). ResultsRecurrence of MR (≥2+ in patients with no/trivial MR at discharge) was found in 112 patients (21.3%) at follow‐up. Compared to patients without recurrence of MR, these patients had higher DYS-PAP values at baseline (60.6±4.4ms vs. 47.2±2.9ms, p<0.001) which significantly worsened at follow‐up (74.4±5.2ms, p=0.002 vs. baseline). In contrast, in patients with no MR recurrence, DYS-PAP was significantly reduced (25.3±4.4ms, p=0.002 vs. baseline). At logistic regression analysis DYS-PAP (odds ratio [OR]: 4.8, 95% Confidence Interval [CI]: 3.4–8.2, p<0.001), was the strongest predictor of recurrent MR with a cutoff ≥58ms (95%CI 51–66ms). The model showed an area under the Receiver Operating Characteristic (ROC) curve of 0.97 (CI 0.94–0.99 [optimism-corrected 0.94; CI 0.89–0.95]) with 98% sensitivity (CI 96–100% [optimism-corrected 95%; CI 91–96%]) and 90% specificity (CI 85–94% [optimism-corrected 87%; CI 82–90%]). ConclusionsDYS-PAP represents a reliable tool to identify patients with ischemic MR who can benefit from restrictive annuloplasty.

Quantitative Real-Time Three-Dimensional Echocardiography Provides New Insight into the Mechanisms of Mitral Valve Regurgitation Post-Repair of Atrioventricular Septal Defect

Mechanisms of mitral valve regurgitation after atrioventricular septal defect repair are unclear. To gain further insight into mitral valve regurgitation, real-time three-dimensional echocardiography was performed in 53 patients after atrioventricular septal defect repair (30 partial and 23 complete) and 40 controls. Mitral valve {x, y, z} coordinates from the annulus, leaflet surface, papillary muscle, and chordal attachments were recorded. Vena contracta area of the regurgitant jet(s) and volume of leaflet prolapse and tethering were measured. Twenty-three patients had mild (group 1) and 30 moderate (group 2) mitral valve regurgitation. Patients in both groups 1 and 2 had more circular annuli than controls. Annular area was greater in group 2 than in group 1 and controls (P < .01). Group 2 had more frequent segmental prolapse in the superior-mural leaflet segment. The anterolateral papillary muscle was more laterally displaced in group 2 than in controls and group 1 at end-diastole (P= .01 and P= .05) and formed a more acute angle with the mitral valve annulus than in controls or group 1 (P= .01). In patients with atrioventricular septal defects, significant mitral valve regurgitation is associated with leaflet prolapse, larger annular area, and lateral papillary muscle displacement.

Papillary muscle rupture: small life-threatening myocardial infarction

We report the case of a 70 years old man admitted to our coronary care unit because of atrial fibrillation, non-ST-elevation myocardial infarction and cardiogenic shock. Emergency coronary angiography showed a 99 % stenosis of the circumflex coronary that was successfully treated with a bare metal stent. Atrial fibrillation was cardioverted to sinus rhythm. Nevertheless, no hemodynamic benefit was observed. Transesophageal echocardiography (TEE) showed rupture of the papillary muscle (PM). The patient underwent emergent mitral valve replacement. Surgical visualization of the mitral valve confirmed the rupture of the antero-lateral PM. The postoperative course was uneventful and the patient recovered fully. This case highlights that even small myocardial infarction may have dramatic clinical presentations such as PM rupture with cardiogenic shock. Clinical suspicion and rapid confirmation of the diagnosis by TEE are essential requirements for successful treatment.

Intracardiac Wegener's Granulomatosis

A healthy 22-year-old woman presented with acute ventricular tachycardia. Cardiac magnetic resonance imaging revealed a mass in the left ventricular cavity. On the basis of these findings, a provisional diagnosis of rhabdomyosarcoma was made and the patient was scheduled to undergo an immediate cardiac surgical procedure. During intraoperative transesophageal echocardiography, the anterolateral papillary muscle (PM) was found to have an abnormal consistency and appeared thickened in the midesophageal (Fig 1A, Fig 1B) and transgastric mid–short axis (Fig 1C) views.

A Mitral Hemi-Arcade: An Unusual Modification of a Rare Anomaly

Congenital anomalies of the mitral valve are rare. A mitral arcade is defined as a fibrous continuity between the papillary muscles and the anterior mitral leaflet creating a hammock like suspension. We present images of a mitral anomaly that consists of a direct attachment of the anterolateral papillary muscle to the anterior mitral leaflet, which we have labeled as a "hemi-arcade." We discuss the surgical findings and review the available literature regarding a mitral "arcade".

Isolated right coronary lesion and anterolateral papillary muscle rupture - case report and review of the literature

Ischemic rupture of the anterolateral papillary muscle is uncommon due to its dual blood supply. It usually follows an ischemic event involving branches of the left circumflex or left anterior descending arteries. We present a case of a patient admitted with an acute inferior wall myocardial infarction and an isolated distal right coronary artery occlusion. Acute mitral regurgitation with rupture of the anterolateral papillary muscle was diagnosed on the fifth post-infarction day. The patient underwent mitral valve replacement and coronary artery bypass grafting to the posterior descending artery. We conclude that anterolateral papillary muscle rupture may also result from an isolated right coronary lesion.

Tethering Symmetry Reflects Advanced Left Ventricular Mechanical Dyssynchrony in Patients With Ischemic Mitral Regurgitation Undergoing Restrictive Mitral Valve Repair

We evaluated the papillary muscle systolic dyssynchrony (DYS-PAP) using two-dimensional speckle tracking echocardiography (2D-STE) in patients with chronic ischemic mitral regurgitation (CIMR) showing different preoperative leaflet pattern and investigated the impact of baseline tethering pattern in the prediction of significant post-repair desynchronized papillary muscle contraction. We recruited 152 CIMR consecutive patients (64.4% male, mean age 65.9 ± 7.1 years) who survived coronary artery bypass grafting (CABG) and (undersized mitral ring annuloplasty, performed between 2001and 2010. The assessment of DYS-PAP was performed preoperatively and at follow-up (median 41.5 months [IQR 23-61]) by 2D-STE in the apical 4-chamber view for anterolateral papillary muscle and apical long-axis view for posteromedial papillary muscle). Based on the cutoff value (anterior-posterior tethering angle ratio α/β ≥ 0.76) patients were classified in 2 groups; symmetrical (group 1, n = 73, mean α/β = 0.81 ± 0.6) and asymmetrical preoperative tethering pattern (group 2, n = 79, mean α/β = 0.66 ± 0.4). Recurrent MR occurred in 67.1% (n = 49) in group 1 versus 3.8% (n = 3) in group 2 (p < 0.001). Comparing both groups at baseline, patients in group 1 had higher DYS-PAP (57.7 ± 5.3 vs 29.8 ± 2.4 ms in group 2, p < 0.001) that significantly worsened at follow-up (78.1 ± 8.8 ms, p < 0.001 versus baseline), whereas in group 2 it improved (26.6 ± 6.0 ms, p < 0.001 versus baseline). Tethering symmetry significantly correlated with DYS-PAP (r = 0.90, p < 0.001) and it was a strong multivariable predictor of significant postoperative DYS-PAP (odds ratio 4.2; 95% confidence level 3.4 to 5.2, p < 0.001). Tethering symmetry is an easy and immediate tool to identify CIMR patients with advanced DYS-PAP who are unlikely to benefit from mitral repair with undersized mitral ring annuloplasty.

Mitral Anterolateral Papillary Muscle Rupture in an Asymptomatic Patient with Mitral Stenosis after Percutaneous Mitral Balloon Valvuloplasty

Percutaneous mitral valvuloplasty is the procedure of choice for the treatment of patients with mitral stenosis and suitable valve anatomy. Papillary muscle rupture is the most worrisome complication of this procedure. Three‐dimensional transesophageal echocardiography (3D TTE) is additive to conventional two‐dimensional imaging in these patients in terms of three‐dimensional perspective and anatomically correct examination. We herein present a case of anterolateral papillary rupture in an asymptomatic patient after percutaneous mitral balloon valvuloplasty demonstrated by 3D TEE.

Parachute mitral valve accompanied by bicuspid aortic valve on three-dimensional transesophageal echocardiography

We report the findings of three-dimensional (3D) transesophageal echocardiography (TEE) in a patient with a parachute mitral valve (MV) accompanied by aortic valve (AV) malformation. The results indicated an enhanced echo in MV anterior leaves, incrassate, and shortened subvalvular chordae tendineae, and posteromedial papillary muscle that had echo reinforcement, calcification, retroposition, and a significant decrease compared with anterolateral papillary muscle. In addition, the anterolateral papillary muscle was huge, with the bilateral papillary muscles fused partly, and the posterior subvalvular chordae tendineae incrassate, shortened, and attached parachute-like to the anterolateral papillary muscle. The MV appeared dome-shaped for the open limit in diastole with an MV area of 1.6cm. Moreover, the left ventricle increased in size and the bicuspid AV was malformed. Continuous wave Doppler angiograph showed that the flow rate increased to 398cm/seconds at the AV orifice area. A 3D form of the MV structure was observed from the left ventricle using 3D-TEE inspection. The anterolateral papillary muscle was fused with its posteromedial homologue. The chordae tendineae was attached to the anterolateral papillary with the parachute-like structure, indicating dome movement.

Finite Element Modeling of Mitral Valve Dynamic Deformation Using Patient-Specific Multi-Slices Computed Tomography Scans

The objective of this study was to develop a patient-specific finite element (FE) model of a human mitral valve. The geometry of the mitral valve was reconstructed from multi-slice computed tomography (MSCT) scans at middle diastole with distinguishable mitral leaflet thickness, chordal origins, chordal insertion points, and papillary muscle locations. Mitral annulus and papillary muscle dynamic motions were also quantified from MSCT scans and prescribed as boundary conditions for the FE simulation. Material properties of the human mitral leaflet tissues were obtained from biaxial tests and characterized by an anisotropic hyperelastic material model. In vivo dynamic closing of the mitral valve was simulated. The closed shape of the mitral valve output from the simulation was similar to the mitral valve geometry reconstructed from MSCT images at middle systole. Forces from the anterolateral and posteromedial papillary muscle groups at middle systole were 4.51N and 5.17N, respectively. The average maximum principal stress of the midsection of the anterior mitral leaflet was approximately 160kPa at the systolic peak. Results demonstrated that the developed FE model could closely replicate in vivo mitral valve dynamic motion during middle diastole and systole. This model may serve as a basis for utilizing computational simulations to obtain a better understanding of mitral valve mechanics, disease and surgical repair.

Incremental value of global systolic dyssynchrony in determining the occurrence of functional mitral regurgitation in patients with left ventricular systolic dysfunction

The aim of this study was to assess the contribution of left ventricular (LV) systolic dyssynchrony to functional mitral regurgitation (MR). Patients (n = 136) with LV systolic dysfunction (ejection fraction <50%) and at least mild MR were prospectively recruited. The effective regurgitant orifice area (EROA) was assessed by the proximal isovelocity surface area method. Left ventricular global systolic dyssynchrony [the maximal difference in time to peak systolic velocity among the 12 LV segments (Ts-Dif)] and regional systolic dyssynchrony (the delay between the anterolateral and posteromedial papillary muscle attaching sites) were assessed by tissue Doppler imaging. Left ventricular global and regional remodelling, systolic function, indices of mitral valvular and annular deformation were also measured. The size of the EROA correlated with the degrees of mitral deformation, LV remodelling, systolic function, and systolic dyssynchrony. By multivariate logistic regression analysis, the mitral valve tenting area (OR = 1.020, P < 0.001) and the Ts-Dif (OR = 1.011, P = 0.034) were independent determinants of significant functional MR (defined by EROA ≥20 mm(2)). From the receiver-operating characteristic curve, the tenting area of 2.7 cm(2) (sensitivity 83%, specificity 82%, AUC 0.86, P < 0.001) and the Ts-Dif of 85 ms (sensitivity 66%, specificity 72%, AUC 0.74, P < 0.001) were associated with significant functional MR. The assessment of Ts-Dif showed an incremental value over the mitral valve tenting area for determining functional MR (χ(2) = 53.92 vs.49.11, P = 0.028). This cross-sectional study showed that LV global, but not regional systolic dyssynchrony, is a determinant of significant functional MR in patients with LV systolic dysfunction, and is incremental to the tenting area that is otherwise the strongest factor for mitral valve deformation.

Complete rupture of the anterolateral papillary muscle complicated with acute myocardial infarction due to diagonal branch occlusion

It is well known that post-infarction papillary muscle rupture of the anterolateral papillary muscle is less frequent than that of the posteromedial papillary muscle. This is thought to be due to a difference in blood supply (single vs dual) of the papillary muscles. Recently, we had two cases in which occlusion of the diagonal branch of the left anterior descending artery was found to be the culprit lesion of acute myocardial infarction leading to complete rupture of the anterolateral papillary muscle. Herein, we report on these two rare successful surgical cases with some review of the literature.

Abstract 9708: Strain Rate of Mitral Papillary Muscles: a New Imaging Prognostic Tool for Mitral Valve Repair

Purpose: New imaging modalities have been employed for the accurate anatomical mapping of the mitral apparatus. The aim of the study was to assess strain of mitral apparatus (papillary muscles and chordae) with a computational speckle tracking model and to associate strain with residual regurgitation post mitral valve surgical repair. Methods: 50 patients with posterior mitral leaflet prolapse underwent mitral valve repair. The left ventricular ejection fraction (LVEF), mitral regurgitant volume (Mvol), the longitudinal strain of the anterolateral papillary muscle (AL), posteromedial papillary muscle (PM) and their chordae (CAL, CPM) were calculated before and 6 months after the repair.Speckle tracking was performed with Toshiba Artida, from apical 2 chamber view and on the same timepoint of the cardiac cycle for all measurements. The groups (pre and post surgical repair) were compared and the strain on papillary muscles was associated with the recurrence of mitral regurgitation post-repair.The global strain of mitral apparatus (Σstrain ) was calculated as: Σstrain= (AL + CAL) - (PM + CPM). Results: Six patients (15%) had residual mitral regurgitation of grade II and III. LVEF before and after the operation did not differ (pre: 69 ± 5%, post: 68.2 ± 3%, p&lt;0.01). PM had significantly higher strain when compared to AL (PM pre: (-18.9) ± (-3)% compared to AL pre: (-4) ± (-1.1) %, p&lt;0.01), while post repair the strain between PM and AL was similar. Patients with residual mitral regurgitation had residual high PM longitudinal strain ((-15.3) ± (-1.4) %). Σstrain overall was significantly reduced post repair (Σstrain pre : (-19.2) ± (-3) % , Σstrain post: (-2.2) ± (-0.6) %, p&lt;0.01). Conclusions: Longitudinal strain of mitral valve apparatus by utilising speckle tracking can be a useful prognostic tool for post repair mitral regurgitation. It seems that a global strain of papillary muscles and chordate (Σstrain) almost equal to zero is associated with trivial regurgitation.

An Accessory Mitral Valve Leaflet Causing Left Ventricular Outflow Tract Obstruction and Associated with Severe Aortic Incompetence

This case report describes a 20-year-old woman with Turner's syndrome who presented with reduced effort tolerance limited by dyspnea. She had previously been on pediatric cardiology follow-up for congenital subvalvular aortic stenosis first diagnosed at age 7. Unfortunately she defaulted after two visits before any intervention could be done. Transthoracic echocardiography demonstrated severe aortic incompetence (AI) with a membrane-like structure in the left ventricular outflow tract (LVOT). The mean pressure gradient across the LVOT on continuous wave Doppler was 41 mmHg. The membranous interventricular septum appeared aneurysmal and it was observed that the "subaortic membrane" had a connection to the anterolateral papillary muscle via a strand of chordal tissue. Further images were captured using two-dimensional and three-dimensional transthoracic and transesophageal echocardiography (iE33, Philips Medical Systems, Andover, MA, USA). After a review of the literature it was concluded that this appeared to be an accessory mitral valve (AMV) leaflet causing LVOT obstruction associated with AI. AMV tissue is a rare congenital malformation causing LVOT obstruction. Because it is so unusual, it may not be immediately recognizable even in a high volume echocardiography laboratory. The clue which helped with the diagnosis was the strand of chordal tissue which connected the mass to the papillary muscle. This anomaly is often associated with LVOT obstruction.