Sharma Sanjeev, Burton Lauren V., Beier Kevin
UTHSC
University of Tennessee - Murfreesboro
Papillary muscle rupture is a rare but potentially fatal complication, typically occurring after myocardial infarction or due to infective endocarditis. Acute rupture often results in severe mitral valve regurgitation, leading to acute life-threatening cardiogenic shock and pulmonary edema. The heart contains 5 papillary muscles originating from the ventricular walls (see . Anatomy of the Heart). These muscles attach to the tricuspid and mitral valve leaflets through the chordae tendineae, preventing ventricular blood regurgitation by stabilizing the valves during systole. Three papillary muscles—anterior, posterior, and septal—attach to the tricuspid valve, whereas two—anterolateral and posteromedial—connect to the mitral valve (see . Mitral Valve Leaflets). Rupture of the tricuspid papillary muscles can occur due to myocardial ischemia, trauma, or infective endocarditis. Papillary muscle dysfunction causes blood to regurgitate through the valves, leading to backflow of blood that can result in left- or right-sided heart failure. Papillary muscle rupture was described in the literature as early as 1948. Visualization of rupture through two-dimensional echocardiography was first reported in 1981. Transesophageal echocardiography was first used to identify the condition in 1985. Papillary muscle rupture is a rare but severe mechanical complication that can occur following an acute myocardial infarction, affecting 0.07% to 0.26% of patients. Despite the condition's rarity, papillary muscle rupture contributes to 5% of postmyocardial infarction mortality. Papillary muscle rupture leads to severe mitral valve regurgitation, often resulting in cardiogenic shock and pulmonary edema, necessitating immediate medical intervention. A classic scenario involves a patient with a myocardial infarction affecting the posterior descending coronary artery's territory who develops sudden, decompensated heart failure 2 to 7 days after the infarction. The anterolateral and posteromedial papillary muscles play a key role in maintaining mitral valve function, with the anterolateral muscle receiving a dual blood supply and the posteromedial muscle supplied solely by the posterior descending coronary artery. Due to this single blood supply, the posteromedial papillary muscle is more likely to rupture following a myocardial infarction. Mortality is very high without timely surgical treatment.
乳头肌破裂是一种罕见但可能致命的并发症，通常发生在心肌梗死后或由感染性心内膜炎引起。急性破裂常导致严重的二尖瓣反流，进而引发急性危及生命的心源性休克和肺水肿。心脏有5个起源于心室壁的乳头肌（见图。心脏解剖）。这些肌肉通过腱索附着于三尖瓣和二尖瓣小叶，在收缩期稳定瓣膜，防止心室血液反流。三个乳头肌——前乳头肌、后乳头肌和间隔乳头肌——附着于三尖瓣，而两个——前外侧乳头肌和后内侧乳头肌——连接到二尖瓣（见图。二尖瓣小叶）。三尖瓣乳头肌破裂可由心肌缺血、创伤或感染性心内膜炎引起。乳头肌功能障碍导致血液通过瓣膜反流，引起血液逆流，可导致左心或右心衰竭。乳头肌破裂早在1948年就有文献记载。1981年首次报道通过二维超声心动图观察到破裂情况。1985年首次使用经食管超声心动图来识别这种情况。乳头肌破裂是一种罕见但严重的机械性并发症，可发生在急性心肌梗死后，影响0.07%至0.26%的患者。尽管这种情况罕见，但乳头肌破裂导致心肌梗死后死亡率的5%。乳头肌破裂导致严重的二尖瓣反流，常导致心源性休克和肺水肿，需要立即进行医疗干预。一个典型的病例是，一名患有影响后降支冠状动脉区域心肌梗死的患者，在梗死后2至7天突然出现失代偿性心力衰竭。前外侧和后内侧乳头肌在维持二尖瓣功能方面起关键作用，前外侧乳头肌接受双重血液供应，而后内侧乳头肌仅由后降支冠状动脉供血。由于这种单一的血液供应，后内侧乳头肌在心肌梗死后更易破裂。若不及时进行手术治疗，死亡率非常高。
