Posteromedial Papillary Muscle Rupture Research Articles

Abstract 12522: Non-Ischemic Papillary Muscle Rupture Due to MRSA Myocarditis

Case Presentation: A 46-year-old male with diabetes, ESRD, and recurrent MRSA bacteremia, presented with septic shock and suffered cardiac arrest. Following resuscitation EKG showed inferolateral ischemia. TTE revealed acute mitral valve regurgitation resulting from posteromedial papillary muscle rupture (PMR). An intra-aortic balloon pump was implanted for cardiogenic shock. Coronary angiography revealed right dominant circulation and thrombotic occlusion of a small caliber distal left circumflex artery (LCX). Emergent mitral valve replacement surgery was performed. Pathologic analysis of the excised muscle and leaflet showed marked acute inflammation, bacterial invasion, and myocyte necrosis, confirming non-ischemic rupture due to MRSA myocarditis. Discussion: PMR predominantly occurs after MI, complicating 0.03% of STEMI cases in the reperfusion era. Non-ischemic causes are rare. Coexistence of myocarditis, infective endocarditis (IE), and MI poses a challenge in determining etiology. Establishing causation guides whether to expedite emergent valve surgery or focus on cardiomyocyte salvage by revascularization. The posteromedial papillary muscle is most commonly involved in PMR due to single blood supply from the PDA (most commonly a branch of the RCA, and less commonly the LCX). Coronary angiography, postoperative histopathology, and culture results determined the etiology of PMR was fulminant MRSA bacteremia culminating in myocarditis. Bacterial colonization and resultant inflammation induced physical and mechanical strain leading to complete rupture. The occluded LCX was incidental, and may have been the result of septic embolization, which occurs in up to 65% of left-sided IE. Albeit rare, non-ischemic etiologies must be considered when the anatomic presentation of acute PMR on TTE is incongruent with angiography. Definitive treatment relies on surgical intervention and mechanical circulatory support is often necessary.

Echocardiographic diagnosis of rupture of mitral valve papillary muscle

ObjectiveTo explore the value of echocardiography in diagnosing papillary muscle rupture (PMR) of the mitral valve, and summarize the characteristic echocardiographic features of different types. MethodsEchocardiograms of 13 PMR patients confirmed by surgery in Wuhan Union Hospital between January 2009 and December 2022 were retrospectively analyzed and their preoperative transthoracic echocardiography (TTE) was compared with surgical findings. ResultsA total of 9020 patients underwent mitral valve repair or replacement surgery during the study period including 13 (0.14%) for PMR. Of the 13 PMRs, 8 cases were partial PMR(P-PMR), 5 cases were complete PMR(C-PMR); 3 cases were anterolateral PMR, and 10 were posteromedial PMR. The diagnostic accuracy, sensitivity, and specificity of the preoperative TTE were 99.9%, 53.8% and 99.9% respectively. Echocardiographic features of 10 patients (5-C-PMR and 5 P-PMR) with detailed TTE and intraoperative transesophageal echocardiography (TEE) data included: both anterior and posterior leaflets prolapse (C-PMR 60% vs P-PMR 60%); flail leaflet (C-PMR100% vs P-PMR 40%); All C-PMRs and P-PMRs have severe, eccentric and lateral regurgitation; flail attachment (chordae tendinae and ruptured PM) at the tip of prolapsed leaflet (C-PMR100% vs P-PMR 60%); high-echo masses resembled “champagne glasses” in 100% of the C-PMR; high-echo masses resembled “lotus-seedpod” in 60% and “dumbbell-shaped” torn PM in remaining 40% of the P-PMR. ConclusionsDifferent PMR subtypes have different echocardiographic characteristics. Combining TTE and TEE can accurately identify the typical features of PMR such as ipsilateral hemipetal leaflet prolapse, high-echoic mass at the tip of the leaflet, massive eccentricity and lateral regurgitation.

Surgical treatment of mechanical complications following acute myocardial infarction. A Case Series.

Background: Acute myocardial infarction can result in ischemic, mechanical, arrhythmic, embolic or inflammatory complications. Despite high operative mortality, the lack of an effective and immediate medical alternative makes the surgery repair the mainstay of current management for these patients. Novel surgical approaches are presented to manage these complications.
 Main body: Mechanical complications presented at the Department of Cardiac Surgery-Tirana University Medical Centre consisted in nine cases during the period January 2008-June 2018: two anterolateral papillary muscle rupture cases (22%), one posteromedial papillary muscle rupture case (11%), two ventricular septal rupture cases (22%), one free ventricle wall rupture case (11%), three chordae tendineae rupture cases (33%), four out of nine patients (44,5%) underwent concomitant CABG intervention. Intra operator mortality is estimated 11% (one out of nine cases). The Department of Cardiac Surgery-Tirana University Medical Centre is limited only in open surgery techniques for repair the post myocardial infarction mechanical complications. To our personal view key reasons for these results are conditioned from lack of medical devices, trained stuff, reliable short and long outcome data from alternative procedures in order to incorporate thus in our daily practice. Further studies should be undertaken not only to create a precise image of the situation, but also to evaluate the results of the possible changes. 
 Key words: Acute myocardial infarction, mechanical complications, papillary muscle rupture, ventricular septal rupture, free ventricle wall rupture, CABG intervention.

P1322 Role of echocardiography in the assessment of mechanical complications of acute myocardial infarction: case report series

Abstract INTRODUCTION The incidence of the mechanical complications of acute myocardial infarction (AMI) has noticeably decreased throughout the world after the era of primary percutaneous coronary intervention (PCI); nonetheless, when they present, the mortality rate continues being high, requiring for their diagnosis an adequate clinical suspicion, followed by intensive care therapy and in most cases, surgical treatment. In the current report we present 4 cases of mechanical complications using transthoracic echocardiography (TTE) as diagnostic tool: a ventricular septal defect, a papillary muscle rupture, a left ventricular (LV) free wall rupture and a ventricular aneurysm. PATIENT 1: A 71-year-old male who presented with inferior AMI and no reperfusion therapy, complicated with transitory AV block, ventricular fibrillation and severe mitral regurgitation secondary to posteromedial papillary muscle rupture (Panel A). He followed surgery with biological mitral valve replacement and PCI of the right coronary artery (RCA). PATIENT 2: A 71-year-old male who presented with anterior AMI and no reperfusion therapy, suddenly showed signs of cardiogenic shock. The TTE demonstrated pericardial effusion associated with an image of thrombus fixed to the antero-apical wall of the LV of 21 mm in dimension, apical segments akinesia and left ventricular ejection fraction (LVEF) of 40% (Panel B). These findings concluded LV free wall rupture, that required urgent surgical repair of the apical region with sphacelated myocardium. PATIENT 3: A68-year-old male, with history of hospitalization 2 months prior for an event of acute coronary syndrome. Admitted again for chest pain, with a TTE that demonstrated a ventricular septal defect associated with intramyocardial dissection, apical thrombus of 17x11 mm in dimension, apical dyskinesis and LVEF of 30% (Panel C). Coronary angiography documented critical obstruction of proximal left anterior descending coronary artery (LAD) and chronic total occlusion of the RCA. He was taken to surgical repair of the defect and coronary artery bypass (CABG). PATIENT 4: A 77-year-old male, with a history of PCI in 2009 (unknown coronary vessel), presented with inferior AMI and no reperfusion therapy. TTE demonstrated an aneurysm in the basal inferior segment of 55x44 mm in dimension, partially thrombosed, with a neck of 23 mm, severe mitral regurgitation and LVEF of 45% (Panel D). Coronary angiography documented multivessel disease with unsuitable coronary anatomy for CABG. CONCLUSIONS The incidence of AMI mechanical complications has decreased noticeably to less than 1% in the era of primary PCI. These include free wall rupture (0.17%), papillary muscle rupture (0.26%) and LV free wall rupture (0.17%). Immediate echocardiographic assessment is needed when clinical findings suggest such complications; urgent treatment is fundamental to improve short term prognosis. Abstract P1322 Figure. Bidimensional TTE images.

Prompt diagnosis of ST-elevation myocardial infarction with papillary muscle rupture by point-of-care ultrasound in the emergency department.

A previously healthy 61-year-old man presented to the emergency department with chest pain and dyspnoea for 6 hours. Examination revealed distress with an apical pansystolic murmur. Initial electrocardiogram showed sinus tachycardia and ST elevation in leads II, III, and aVF compatible with an inferior ST-elevation myocardial infarction. Point-of-care echocardiography in the emergency department showed a flail anterior mitral leaflet and severe mitral regurgitation, leading to a provisional diagnosis of papillary muscle rupture. Emergency cardiac catheterization showed 100%, 80%, and 70% occlusion of the middle right coronary, left anterior descending, and left circumflex arteries, respectively. An emergency triple vessel coronary artery bypass grafting and mitral valve replacement was performed. Posteromedial papillary muscle rupture resulting in mitral regurgitation was confirmed intraoperatively. The patient recovered uneventfully. In the absence of primary percutaneous coronary intervention, thrombolysis decisions should be made with extreme caution if mechanical complications of ST-elevation myocardial infarction are suspected.

Partial posteromedial papillary muscle rupture as an early complication after acute inferior ST-elevation myocardial infarction treated with primary percutaneous intervention.

Partial posteromedial papillary muscle rupture as an early complication after acute inferior ST-elevation myocardial infarction treated with primary percutaneous intervention.

Posteromedial Papillary Muscle Rupture Following Percutaneous Mitral Balloon Valvotomy

Mini‐AbstractWe report a case of Inoue balloon mitral valvotomy in a patient with low echo score that was complicated by severe regurgitation caused by a rupture of a papillary muscle, which only became apparent the day after the procedure. Our case highlights the importance of the follow‐up of patients undergoing balloon mitral valvotomy even following a successful procedure on suitable valves.

Real Time Three‐Dimensional Transesophageal Echocardiography in Partial Posteromedial Papillary Muscle Rupture

A 60-year-old hypertensive male with non-ST segment elevation myocardial infarction had a hyperdynamic LV with mild posterior leaflet mitral valve prolapse without significant regurgitation on transthoracic echocardiogram. Two-dimensional (2D) TEE showed severe mitral regurgitation with prolapse of P2 and P3 scallops. Posteromedial papillary muscle rupture was suspected. Three-dimensional (3D) TEE demonstrated severely prolapsing P2 and P3 valve scallops with a clear view of the partially ruptured posteromedial papillary muscle. Patient underwent emergency coronary bypass and mitral valve replacement. Surgical pathology of papillary muscle confirmed coagulative necrosis. 3D TEE was superior in identifying the partial posteromedial papillary muscle rupture.

Echo Features of Posteromedial Papillary Muscle Rupture without Papillary Muscle Prolapse into the Left Atrium

(Echocardiography 2011;28:1046-1048) Movie clip S1: Bedside echocardiography with parasternal long-axis imaging demonstrates aneurysmal formation of the inferobasal segment. Aortic sclerosis is noted. There is no mitral valve prolapse seen. Movie clip S2: Parasternal long-axis imaging demonstrated ``chaotic'' echoes within the LV. Compare this movie with that from the previous day, before clinical occurrence of papillary muscle rupture (movie clip S1). Movie clip S3: Transesophageal echocardiography within the esophagus at 120° demonstrates marked prolapse of the mitral leaflets. Chaotic motion of the ruptured papillary muscle head is noted, but it does not prolapse into the left atrium. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Rotura espontánea de músculo papilar con coronarias angiográficamente normales

Papillary muscle rupture is an unusual pathology, commonly being a mechanical complication of an acute myocardial infarction or a blunt chest trauma. In this case report we describe a patient with a spontaneous complete posteromedial papillary muscle rupture, secondary to an isolated papillary muscle infarction, in the absence of coronary artery disease, resulting in severe mitral regurgitation, cardiogenic shock and uneventful urgent mitral valve replacement. The clinical and histopathologic literature, and mechanisms to explain this kind of rupture, are reviewed.

Rupture of posteromedial papillary muscle as a mechanism of death in dilated cardiomyopathy

The pathogenesis of mitral regurgitation in dilated cardiomyopathy is ascribed to several mechanisms. The authors describe the case of an adult male with idiopathic dilated cardiomyopathy who developed myocardial infarction in the absence of coronary atherosclerosis and died from acute lung edema following rupture of a papillary muscle of the left ventricle. The possibility of coronary embolism could not be ruled out.

Posteromedial papillary muscle rupture as a result of right coronary artery occlusion after blunt chest injury

Posteromedial papillary muscle rupture as a result of right coronary artery occlusion after blunt chest injury