Acute onset of extreme shortness of breath.
Acute papillary muscle rupture has long been recognized as an uncommon, often catastrophic, cardiac emergency leading to massive mitral regurgitation, congestive heart failure, cardiogenic shock, and a nearly 80% mortality rate within the first 24 hours. (1) Its stated frequency has most often been estimated by autopsy data such that, in one series, two cases among 6,000 consecutive autopsies were identified. (2) The most common known cause of the rupture is preceding acute myocardial infarct (AMI), two to seven days prior, in the context of significant (>75% stenosis) atherosclerotic coronary artery disease (CAD), a pathogenic association that appears described in scientific literature that dates back to the late 1800s. (3) In the post-AMI patient population, ruptured papillary muscle is said to occur in less than 1% of all cases but account for up to 5% of all deaths. (4) The posteromedial papillary muscle is preferentially involved five to eight times more often than its anterolateral counterpart, likely due to the fact that its vascular source relies solely on the posterior descending branch of a right-dominant coronary artery. Whereas the anterolateral papillary muscle is dually supplied by branches both of the left anterior descending (first diagonal), as well as the left circumflex (first obtuse marginal) coronary arteries. (5) With the rarity of the condition, no particular constellation of risk factors predisposing AMI/CAD patients to papillary muscle rupture has yet to be described or understood. (4)
With no clinical or pathological evidence either before death or at the time of autopsy for AMI or for CAD, the current case is classifiable as a spontaneous papillary muscle rupture (SPMR). These cases of non-AMI, non-CAD SPMR are exceedingly uncommon with very few described and retrievable in the English medical literature. (6-12) In some cases of SPMR, various mechanisms for rupture have been documented, ranging from endocarditis and syphilis to trauma, as well as small vascular arteritis, sickle cell anemia, and aneurysms. (6) However, in a small subset of SPMR cases, no clearly associated mechanism is evident. To our knowledge, the current case is the fifth reported case wherein no etiologic cause or preceding event is identifiable, and appears to be only the second such case wherein rupture involves the anterolateral papillary muscle. Features from these cases are compared in Table 1, where it is demonstrated that, in all but one case, there is either pathologic evidence and/or a clinical history of hypertension (HTN). Another shared feature illustrated in the table is the histopathologic evidence of ischemic necrosis, or infarction, that is isolated to the papillary muscle bundle itself rather than involving the adjacent left ventricular myocardium (Figure 2a-b). In a 1990 review of 110 consecutive adult hearts retrieved at autopsy, Waters documents evidence of papillary muscle ischemia (PMI) far more frequently (77% of cases) than ischemic changes in the ventricular walls (33% of cases). Acute PMI, specifically, was identified in 23% of post-mortem hearts. Still further, Waters suggests that both cardiomegaly and HTN increase the risk for acute PMI since 42% of hearts weighing more than 500 gm, and >1/3 of hypertensive patients had an acutely infarcted papillary muscle. (13) This causal relationship may be partly explained by the hypothesis that these patients are at a higher risk both for subendocardial hypoperfusion, as well as for PMI, because of an increased resistance to perfusion and a wider separation of a relatively lower volume of perfusing capillaries that results from the greater ventricular mass and wider myocyte fibers. (13) The case presented here is notable and unique, both for the patient's young age and clinical history of hypertension and for the extreme cardiomegaly (1,020 gm) and left ventricular hypertrophy. Another feature of interest is the long segment (4 cm) of myocardial bridging at significant depths of 0.4-0.7 cm. What role the bridging may have played on possible transient occlusion of the mid-left anterior descending coronary artery in the region of the origin for the first diagonal branch that serves to supply the anterolateral papillary muscle is unclear. Further reports on cases of SPMR, particularly of the anterolateral muscle where myocardial bridging, marked cardiomegaly, and ventricular hypertrophy are observed, are needed.
The authors would like to gratefully acknowledge the support of the Orleans Parish Coroner's Office: Dr. Frank Minyard and Chief Investigator John Gagliano for providing the case material for this report.
(1.) Sanders RJ, Neubeurger KT, Ravin A. (1957). Rupture of papillary muscles: occurrence of rupture of posterior muscle in posterior myocardial infarction. Dis Chest 31:316-323.
(2.) Stevenson RR, Turner WJ. (1935). Rupture of papillary muscle as cause of sudden death. Bull Johns Hopkins Hosp. 57:235-242.
(3.) Davison S. (1948). Spontaneous rupture of papillary muscle: a report of three cases and review of literature. J Mt Sinai Hosp 14:941-953.
(4.) Zotz R, Dohmen G, Genth S, et al. (1993). Diagnosis of papillary muscle rupture after acute myocardial infarction by transthoracic and transesophageal echocardiography. Clin Cardiol 16:665-670.
(5.) Barbour DJ, Roberts WC. (1986). Rupture of a left ventricular papillary muscle during acute myocardial infarction: analysis of 22 necropsy patients. J Am Coll Cardiol 8:558-565.
(6.) Lazar HL, Bernard SA. (2010). Acute anterolateral papillary muscle rupture in the absence of coronary artery disease. J Card Surg 25:518519.
(7.) Tsuboi H, Ikeda Y, Minami Y, et al. (1997). Mitral regurgitation secondary to spontaneous papillary muscle rupture: report of a case. Surg Today. 27(12):1185-1187.
(8.) Stirling GA, Lambert BF. (1960). Spontaneous rupture of a papillary muscle of the heart. Br Heart J. 22(4):594-596.
(9.) Nurkalem Z, Gorgulu S, Orhan A, et al. (2008). Papillary muscle rupture secondary to infective endocarditis. Echocardiography. 25:901-903.
(10.) Lee H, Ruzsics, B, Schoepf UJ, et al. (2009). New-onset heart failure caused by spontaneous papillary muscle rupture: Diagnosis with dual-source computed tomographic coronary angiography. J Thorac Cardiovasc Surg. 137(1):19-21.
(11.) Ripoll Vera T, Forteza Alberti JF, Fernandez Palomeque C, et al. (2001). Spontaneous rupture of the papillary muscle with angiographically normal coronary vessels. Rev Esp Cardiol 54:10101012.
(12.) Weiss ST, Coppola J, Gambino J, et al. (1998). Isolated acute papillary muscle infarction in the absence of coronary artery disease resulting in cardiogenic shock and emergent mitral valve replacement. Cathet Cardiovasc Diagn 43:185-189.
(13.) Waters BL. (1990). Clinical and pathologic factors contributing to acute papillary muscle ischemia. Arch Pathol Lab Med 114:601-604.
Robin R. McGoey, MD; Bradley Cheek, MD; Neeraj Jain, MD; William P Newman, MD
In the Department of Pathology at Louisiana State University Health Sciences Center in New Orleans, Dr. McGoey is an Associate Professor of Pathology and Residency Program Director, Dr. Cheek is a third-year Pathology Resident, and Dr. Newman is a Professor of Pathology. In the Department of Medicine, Dr. Jain is an Associate Professor of Cardiology.
Table 1: Clinical and pathologic features of current case compared to reported cases in the literature of non-AMI/non-CAD-associated SPMR with PMI. CTR = chest:thoracic ratio; LVH: left ventricular hypertrophy; HTN: hypertension Age/ Gender Anterior or Clinical Posterior Outcome Muscle Current Case Male, 33y Anterior, Fatal complete Lazar et al. (6) Female, 76y Anterior, Mitral valve complete replacement, survival Tsuboi et al. (7) Male, 77y Posterior Mitral valve replacement, survival Lee et al. (10) Female, 49y Posterior, Mitral valve complete replacement, survival Ripoll Vera et Female, 73y Posterior, Mitral valve al. (11) complete replacement, survival Weiss et al. (12) Female, 76y Posterior, Mitral valve complete replacement, survival Pathologic Signs or Pathology of Clinical History of Ruptured Papillary HTN Muscle Current Case Cardiomegaly, LVH, Acute infarct (ischemic history of HTN necrosis) Lazar et al. (6) None Acute infarct (ischemic necrosis) with remote infarct (scar) Tsuboi et al. (7) CTR 67% Remote infarct (scar) Lee et al. (10) LVH, history of HTN Acute infarct (ischemic necrosis) Ripoll Vera et LVH, history of HTN Acute infarct (ischemic al. (11) necrosis) Weiss et al. (12) LVH, history of HTN Acute infarct (ischemic necrosis)
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||Pathology Image of the Month|
|Author:||McGoey, Robin R.; Cheek, Bradley; Jain, Neeraj; Newman, William P.|
|Publication:||The Journal of the Louisiana State Medical Society|
|Article Type:||Clinical report|
|Date:||May 1, 2013|
|Previous Article:||A case of disseminated cryptococcosis with skin manifestations in a patient with newly diagnosed HIV.|
|Next Article:||Summary of actions of the meeting of the board of governors: September 18, 2013.|