Cardiac rupture--challenge in diagnosis and management

Prediction of rupture in acute myocardial infarction

In two patient series including 809 and 327 patients, respectively, with acute myocardial infarction we have compared those who died in myocardial rupture (verified at autopsy, Group A) with those who died without rupture (autopsied, Group B), and those who survived hospitalization (Group C) with regard to previous history and clinical course in hospital. Rupture among autopsied patients was observed in 45% and 40% of the cases in the respective studies. Previous infarction was observed in each study as 0% and 0% in Group A compared with 25% and 31% in Group B, and 20% and 34% in Group C. Previous angina pectoris was observed in 26% and 22% in Group A compared with 50% and 54% in Group B and 52% and 54% in Group C. Maximum serum enzyme activity in Group A did not differ from Group B, but was higher than in Group C (p less than 0.001). Group A patients tended to have a higher initial pain score and a higher requirement of analgesics compared with other groups, whereas initial heart rate or systolic blood pressure did not differ in these patients compared to others. We thus conclude that patients with myocardial rupture have a very low occurrence of previous myocardial infarction and angina pectoris, and that their pain course appears to be particularly severe in the acute phase.

Myocardial rupture in acute myocardial infarction: urgent management

Myocardial rupture complicated acute myocardial infarction in a 50 year old man. Resuscitation was started immediately and he was treated with pericardiocentesis and a massive intravascular infusion of fluid. The torn area was plicated with Teflon felt and reinforced with an uninterrupted suture. The postoperative course was uncomplicated. This report points out the crucial importance of prompt clinical recognition and management of the acute stage of cardiac rupture in acute myocardial infarction.

Effect of myocyte necrosis on strength, strain, and stiffness of isolated myocardial strips

Cardiac rupture accounts for 8% to 10% of patient deaths after acute myocardial infarction, suggesting that myocyte necrosis weakens the ventricular wall in the initial days after occlusion. To test this theory, permanent occlusion of the left anterior descending coronary artery was performed in dogs. Twenty-four hours after occlusion, the tensile strength, strain at rupture, and stiffness of necrotic epicardium, midmyocardium, endocardium, subepicardium, and the visceral pericardium (VP) were quantified and compared with those of noninfarcted cardiac tissue. The relationship between tensile strength, stiffness, and collagen content was also examined. These material properties did not differ between necrotic and normal myocardium in any of the layers, indicating that myocyte necrosis, per se, does not weaken the myocardium. In both necrotic and normal tissue, marked transmural heterogeneity was observed; tensile strength of the endo- and epicardium (21.3 +/- 3.3 and 21.3 +/- 3.2 gm/mm2) was significantly greater (p less than 0.01) than that of the midmyocardium (4.0 +/- 0.3 gm/mm2) and subepicardium (5.0 +/- 0.5 gm/mm2), whereas the VP was substantially stronger (greater than 100 gm/mm2) than any myocardial layer. Similar results were obtained for stiffness. In contrast, strain at rupture did not vary significantly among myocardial layers and ranged from 0.40 +/- 0.03 (VP) to 0.53 +/- 0.03 (endocardium). Both tensile strength and stiffness of the myocardial layers were found to correlate directly with their collagen content: the higher the hydroxyproline concentration, the greater the tensile strength (r = 0.83). These results support the concept that the collagen fibroskeleton is an important determinant of the material properties of the myocardium. As myocyte necrosis, per se, did not affect tensile strength, we tentatively conclude that cardiac rupture may be a consequence of a defect or weakness in the collagenous framework of the heart.

False aneurysm formation after ventricular rupture associated with reinfarction following successful thrombolysis

A 69-year-old woman underwent successful thrombolysis for total occlusion in the right coronary artery using urokinase. One week later, the patient developed reinfarction in the area supplied by the right coronary artery, followed by ventricular rupture. She was resuscitated with drainage of the pericardial effusion. Cardiac catheterization confirmed that the site of the right coronary artery reocclusion was identical to that in the acute phase. A false aneurysm developed over the true aneurysm located in the inferior portion of the left ventricle as demonstrated by a ventriculogram at the convalescent stage and at surgery. The orifice of the false aneurysm has closed by suture.

Pseudosepsis after myocardial infarction. Unusual presentation of anterior wall rupture and left ventricular pseudoaneurysm

Left ventricular pseudoaneurysm complicating myocardial infarction is extremely rare. A case of left ventricular anterolateral pseudoaneurysm with its initial presentation mimicking septic shock is reported. The need for urgent resection is stressed due to the high incidence of spontaneous rupture and death regardless of the age or the size of the pseudoaneurysm.

Cardiac rupture in patients with acute myocardial infarction

The occurrence of myocardial rupture was evaluated in an unselected population of 1,737 patients with acute myocardial infarction (AMI). Patients with cardiac rupture after AMI were compared with age- and sex-matched control patients with fatal AMI not related to rupture and with AMI survivors discharged home. Rupture was found in 40 patients (15.7 percent of hospital deaths), or 2.3 percent of all cases of AMI. At the highest risk for rupture were women aged 60 to 69, although the age distribution did not differ significantly from that of patients dying of other causes. More patients with myocardial rupture had hypertension during hospitalization, persistent pain, and inferior wall myocardial infarction when compared with controls. The majority (95 percent) of cardiac ruptures occurred within the first six days, 40 percent within the first 24 hours after the onset of symptoms. Approximately 20 percent of ruptures were diagnosed as subacute; in only two was surgical intervention attempted unsuccessfully. The high-risk group of patients should be carefully monitored within the first six days after the onset of symptoms of AMI in an effort to prevent myocardial rupture.

Classification of cardiac rupture complicated in myocardial infarction. Pathological study of 32 cases

Thirty of 32 cases with cardiac rupture (CR) complications in the myocardial infarction were found out of a total of 91 cases of acute myocardial infarction (AMI). The mean age of the ruptured group in females was significantly younger than that of the non-ruptured group. Twenty-one cases showed free wall rupture of the left ventricle, six perforation of ventricular septum and three double rupture. All cardiac ruptures occurred in cases of transmural infarction. The age of AMI was histologically estimated. Nine cases complicated within the first 24 hours of AMI showed rupture of the left anterior wall. CR in the periphery within the infarct occurred at any time during the first week after onset, and cases of the central rupture were increased in number after the 3rd day of AMI. Pathologic findings indicated that elevated wall tension was considered to be most closely related to the cause of CR. Thirty two cases of CR were classified into three types: (1) blowout type, (2) hemorrhagic dissecting type, and (3) thinning-with-rupture type. Hemorrhagic dissecting type was characterized by multiple endocardial ulcers and fissure canals extending from the ulcer with hemorrhage in the surrounding myocardium. Complex fissure was seen in two cases of this type.

Mitral valve replacement early after myocardial infarction: attendant high risk of left ventricular rupture

Between 1969 and 1983, 608 patients underwent mitral valve replacement surgery at Cedars-Sinai Medical Center. Perioperative rupture of the left ventricular myocardium complicated seven operations (1.2%), five of them in the 247 patients with concomitant ischemic heart disease. Six ruptures were fatal. Relative incidences of seven previously hypothesized predisposing factors were determined for patients with and without myocardial rupture. In addition, because of the apparent frequency of association with ischemic heart disease and because all ruptures were posterior or posterolateral, patients were also categorized by prior history of posterior myocardial infarction: 177 patients had none, whereas 49 patients had a remote and 21 patients a recent (less than or equal to 1 month) posterior wall infarct. Four ruptures (accounting for 57% of all ruptures) occurred in the 21 patients (19% incidence) with a recent posterior infarct, compared with only three ruptures in the 587 patients (0.5%) without a recent posterior wall infarct (p = 0.000). None of the factors of age, sex, valve pathology, etiology of valve lesion, concomitant coronary disease, valve substitute or intraoperative myocardial preservation were associated with perioperative rupture. These data establish a low overall incidence of ventricular rupture after mitral valve replacement, high fatality and possible etiologic association with recent posterior wall infarction.

Hemodynamic abnormalities in acute myocardial infarction

Great strides have been made in the management of patients with acute myocardial infarction since the advent of coronary care units. However, congestive heart failure continues to be the major cause of in-hospital mortality. The accurate diagnosis and classification of hemodynamic abnormalities allow the application of specific therapies for each patient. Because clinicians can now routinely measure left and right ventricular preload, systemic and pulmonary vascular resistance, cardiac output, and arteriovenous oxygen difference, pharmacologic and surgical interventions can be applied in a scientific manner. In addition, mechanical complications can be promptly recognized and aggressively treated. Although the mortality rate for patients with severe left ventricular dysfunction after myocardial infarction remains high, expert management offers an improved prognosis for many patients.

Healing after myocardial infarction in the dog: changes in infarct hydroxyproline and topography

Temporal changes in infarct collagen and left ventricular topography during healing after myocardial infarction were studied in 132 dogs with coronary artery ligation: 8 sham dogs and 13 with no infarction (controls) and 111 with infarction (3 at 1 day, 54 at 2 days, 25 at 7 days, 3 at 2 weeks, 9 at 4 weeks and 17 at 6 weeks). Myocardial hydroxyproline (a marker of collagen) was measured by spectrophotometry and pathologic infarct size, arteriographic occluded bed size and topography by computerized planimetry of weighed left ventricular rings. Over 6 weeks, hydroxyproline was unchanged in normal regions (average 4.20 mg/g dry weight) but increased progressively between 7 days and 6 weeks (9.94 versus 55.55 mg/g, p less than 0.001) in infarct zones. Progressive infarct contraction occurred over 6 weeks, with infarct size at 6 weeks being 40% less than at 2 days (9.7 versus 16.3% of the left ventricle, p less than 0.001), although total infarct hydroxyproline was directly related to infarct size at each time period (r = 0.73 to 0.81, p less than or equal to 0.05). Significant (p less than or equal to 0.05) left ventricular topographic changes in infarct hearts compared with control hearts included: 1) increase in cavity area (5.0 versus 3.9 cm2), endocardial circumference (8.8 versus 7.4 cm) and expansion index (infarct/normal endocardial segment length, 1.21 versus 1.02) by 7 days; and 2) decrease in thinning ratio (infarct/normal wall thickness, 0.71 versus 0.98) by 6 weeks. Also, compared with 2 day infarcts, by 6 weeks infarct area was decreased (1.8 versus 3.4 cm2) and the noninfarcted segment length increased (6.9 versus 5.4 cm). Changes in hydroxyproline and topography were similar for anterior (n = 54) and posterior (n = 57) infarcts. Thus, healing in canine infarcts is associated with cavity dilation and infarct expansion within 7 days followed by infarct contraction and thinning by 6 weeks, whereas collagen increases between 7 days and 6 weeks. Collagen deposition in expanded and thinned infarct segments explains the permanent regional shape distortion associated with ventricular aneurysms.

Effects of reperfusion after coronary artery occlusion on post-infarction scar tissue

Early reperfusion after a coronary occlusion may reduce myocardial infarct size, but late reperfusion into necrotic myocardium may alter post-infarction healing. In rabbits, we compared 1- or 3-week-old scars resulting from permanent coronary occlusion to those resulting from a 1- or 3-hour occlusion followed by reperfusion. Reperfusion at 1 hour post-occlusion did not affect scar mechanical properties assessed at 1 week post-infarction, but at 3 weeks post-infarction, these scars had a tensile strength significantly lower than those not reperfused (78 +/- 11 vs. 158 +/- 15 g/mm2, P less than 0.001). They also were composed of a mixture of fibrous tissue (58 +/- 8%) and myocytes (43 +/- 8%) with a hydroxyproline content of 23 +/- 2.5 mg/g dry weight. The nonreperfused scars had a higher proportion of fibrous tissue (73 +/- 3%) by histological evaluation and a 35% higher hydroxyproline content (31 +/- 2 mg/g dry weight, P less than 0.001) than the scars reperfused after 1 hour. In contrast, 3-week-old scars resulting from "late" reperfusion at 3 hours post-occlusion were similar to nonreperfused scars in fibrous tissue composition and hydroxyproline content. Nonetheless, the tensile strength of these scars reperfused 3 hours post-occlusion was significantly less than that of the nonreperfused scars (72 +/- 5 vs. 158 +/- 15 g/mm2, P less than 0.001). The lower tensile strength was associated with a lower collagen cross-link density in this reperfused group of scars. At physiological stress levels (approximately 3 g/mm2), all groups of reperfused and nonreperfused scars had similar mechanical properties in terms of natural strain, stiffness, creep, and stress relaxation. Thus, although the reperfused scars ruptured more easily at high stresses, when assessed at physiological stresses their mechanical properties were not significantly different from those of nonreperfused scars.

Rupture of the myocardium. Occurrence and risk factors

The occurrence of myocardial rupture was studied in a well defined unselected population of patients with acute myocardial infarction, and the group of patients who died of rupture of the heart were compared with two control groups. Of a total of 3960 patients, 1746 (44%) fulfilled the diagnostic criteria for acute myocardial infarction. Rupture was defined solely on the basis of the presence of a pathological passage through part of the myocardium, either the free wall of the left ventricle or the septum, found at necropsy or during operation. Two controls were selected for each patient and matched for age and sex, one (control group A) with acute myocardial infarction having died in hospital but not of rupture (non-rupture cardiac death) and one (control group B) with acute myocardial infarction having survived the hospital stay. Necropsy was performed in 75% of all fatal cases with acute myocardial infarction. The total hospital mortality was 19%, the highest mortality being among women over 70 years (29%). Ruptures (n = 56) were found in 17% of the hospital deaths, or 3.2% of all cases of acute myocardial infarction. Women aged less than 70 had the highest incidence of rupture, 42% of deaths being due to rupture. The mean age for patients with rupture and controls was 70.5 years. The median time after admission to death was approximately 50 hours for patients and control group A. Thirty per cent of the patients with rupture occurred within 24 hours of the initial symptoms occurring. Angina and previous acute myocardial infarction were more common among control group A. Patients with rupture and control group B were mostly relatively free of previous cardiovascular or other diseases (chronic angina pectoris ( > 2 months) and previous myocardial infarction). Sustained hypertension during admission to the coronary care unit was more common in patients than in control group A. Hypotension and shock were more common among control group A. Most (79%) of the patients who subsequently ruptured did not receive any corticosteroids at all during the hospital stay. Severe heart failure and antiarrhythmic treatment were more uncommon among patients than among control group A. Patients with rupture received analgesics approximately three times a day throughout their stay. Control group B received analgesics mostly during the first 24 hours. Thus female patients, patients with first infarcts, and patients with sustained chest pain should be investigated for the possibility of rupture. As many as one third (32%) of ruptures may be subacute, and therefore time is available for diagnosis and surgery.

Potential prevention of myocardial rupture resulting from acute myocardial infarction

The clinical characteristics of 30 cases of myocardial rupture resulting from acute myocardial infarction were analyzed. Predisposing factors of myocardial rupture appeared to be the following (1) age 60 years or older, (2) female, (3) no previous history of angina or myocardial infarction, (4) hypertension on admission, (5) persistent or recurrent chest pain, (6) physical activity and/or emotional unrest, (7) less than 10 days since the onset of myocardial infarction. From 1979 to 1982, we tried to eliminate these risk factors in the acute stage of myocardial infarction, of which hypertension appeared to be the most important and main correlating factor. The incidence of myocardial rupture before elimination of risk factors was 31.2% (26 of 84 patients) which was reduced to 8.8% after elimination. In the years 1981 and 1982, only two cases of myocardial rupture were found in each year, 4.3% and 5.6% of MI patients, respectively.

Surgical implications of low cardiac output syndrome after myocardial infarction

There is a spectrum of conditions that can occur after severe myocardial infarction which cause inadequate cardiac output. Severe and generalized infarction may result in inadequate perfusion of sufficient myocardium to maintain the cardiac work load. Management is limited to supportive measures, including the use of the intraaortic balloon pump. More localized defects of myocardial blood supply can give rise to myocardial rupture. These ruptures may occur in the free wall, within the septum, or within a papillary muscle. Conservative therapy is only indicated as long as improvement continues. Surgical measures should not be delayed in the face of clinical deterioration. They consist of debridement of dead tissue and repair of the defect (or mitral valve replacement if papillary muscle rupture is present).

Incidence of pericardial effusions in acute myocardial infarctions

To study the incidence of pericardial effusions in the first 72 hours after myocardial infarction, M-mode echocardiograms were performed on 90 of 100 consecutive patients with acute myocardial infarctions. Pericardial effusions were documented in five patients (5.6 percent), four of which resolved without sequelae by the time of discharge. The remaining patient died of presumed myocardial rupture. Pericardial effusions tended to be more common in patients with anterior or anterolateral infarcts and in those who had received intracoronary streptokinase (p less than .10). No patient with postinfarction pericarditis had an effusion.

Bedside evaluation in cardiac emergencies. Criteria for rapid diagnosis

Because timely diagnosis and treatment are essential in cardiac emergencies, every physician who provides primary critical care should master the art of cardiovascular examination. In particular, this requires patience and skill at auscultation, as subtle differences in murmurs, for example, often differentiate two conditions. With a tentative diagnosis, the physician can then choose only the necessary confirmatory tests.

Subacute heart rupture and hemopericardium following acute myocardial infarction: report of successful treatment and ten year follow-up

Hemopericardium complicating acute myocardial infarction generally has a poor prognosis. Two cases of this complication, one due to subacute rupture of the free left ventricular wall, are reported. Both patients are still alive and well ten years after urgent surgical intervention. Good long-term results are possible in this condition if diagnosis and surgical intervention are not delayed.

Atypical echocardiographic and angiographic presentation of a postoperative pseudoaneurysm of the left ventricle after repair of a true aneurysm

Subsequent to the repair of a true aneurysm from the posteromedial-basal aspect of the left ventricle, a 58 year old man developed a draining wound at the site of the sternotomy. Two-dimensional echocardiography revealed recurrence of the aneurysm at the site of the previous aneurysm repair. This aneurysm had a wide neck and looked similar in appearance to the previous true aneurysm. However, at surgery the patient was found to have a ventricular pseudoaneurysm with a cardiocutaneous fistula.

Myocardial healing and repair after experimental infarction in the rabbit

Adequacy of healing after acute myocardial infarction may determine the incidence of postmyocardial infarction rupture and ventricular aneurysm. Accordingly, in 36 rabbits, from 1 to 8 days after coronary ligation, and in 18 shams, we measured collagen formation and mechanical resistance of the infarcted left ventricle to stretch and rupture. Prolyl hydroxylase, an intracellular enzyme of collagen synthesis, increased from control activity of 3970 +/- 431 to 9224 +/- 643 counts/min per mg (cpm/mg) extractable protein (P less than 0.01) at 48 hours and was nearly maximal at 3 days postmyocardial infarction (14,518 +/- 2,030 cpm/mg, P less than 0.01). Lysyl oxidase, an extracellular collagen cross-linkage enzyme, increased from control activity of 29.6 +/- 4.8 to 74.7 +/- 18.8 cpm/mg extractable protein (P less than 0.01) at 72 hours and peaked at 121.5 +/- 7.3 (P less than 0.01) 4-6 days postmyocardial infarction. Hydroxyproline, a measure of collagen content, increased from control of 2.8 +/- 0.2 to 5.3 +/- 0.6 mg/g dry weight (P less than 0.05) at 72 hours and continued to increase at 8 days postmyocardial infarction (14.5 +/- 1.7 mg/g dry weight; P less than 0.01). When enzyme activities and hydroxyproline content were expressed relative to other reference bases, including DNA, tissue protein, dry weight, and total left ventricle, similar results were obtained. The mechanical properties of the infarcted left ventricle were determined by filling a balloon in the excised left ventricle until rupture. The rupture threshold in the normal left ventricle, [664 +/- 43 mm Hg (n = 16)], was not significantly different from that of the infarcted left ventricle on days 1-8 postmyocardial infarction. However, left ventricular rupture occurred more often through the myocardial infarction on days 1-4 postmyocardial infarction (59%) than on days 6 and 8 (18%; P = 0.03) when collagen content had significantly increased. Wall stress at the point of rupture in left ventricles from shams and normals was 30 +/- 2 g/mm2; tensile strength in isolated left ventricle muscle strips was 25 +/- 4 g/mm2 and in isolated scar strips at 7 days postmyocardial infarction was 59 +/- 7 g/mm2. The passive stiffness of the infarcted left ventricle increased from control of 61 +/- 5 to 94 +/- 6 mm Hg/100 microliters (P less than 0.05) at 4 days and 100 +/- 7 mm Hg/100 microliters (P less than 0.01) at 6 days postmyocardial infarction. Stiffness correlated with hydroxyproline content over the 8 days postmyocardial infarction (r = 0.599; P less than 0.001). Thus, the acutely infarcted ventricle was highly resistant to rupture during the initial 48 hours postmyocardial infarction, before any increase in collagen occurred. This result suggests that the preinfarction collagen content has an important role in preventing rupture. After 72 hours postmyocardial infarction, collagen synthesis appeared to be a determinant of infarct stiffness and resistance of the infarcted ventricle to rupture.

Surgical salvage of heart rupture: report of two cases and review of the literature

Two patients who sustained cardiac rupture complicating recent myocardial infarction were salvaged by expeditious diagnosis and surgical treatment. The cases of 9 other similar patients have been reported in the English-language literature. The cases of these 11 patients were reviewed in an attempt to find common clinical, pathological, and therapeutic features that might have been instrumental in the successful outcome of this usually fatal complication.

Early degradation of collagen after acute myocardial infarction in the rat

After acute myocardial infarction (MI), proteolysis of necrotic myocardium is mediated by infiltrating inflammatory cells at the infarct margins. Collagen forms a structural fibroskeleton in healthy myocardium, and after MI this collagen may continue to provide significant tensile strength to the necrotic muscle wall. To determine whether collagen is also degraded (which might decrease infarct wall strength) and, if so, whether inflammatory cell proteases are implicated, hydroxyproline was measured from infarct zone and normal zone tissue from 24-hour infarcts produced in control rats and in rats made leukopenic (white blood cell count less than 300/mm3) by prior whole-body irradiation. Hydroxyproline was measured after precipitation of tissue homogenates with trichloroacetic acid to separate partially degraded collagen from larger collagen molecules that might retain structural importance. At 24 hours, there was significant (25%) collagen degradation in the infarct zone (p less than 0.01) in control rats but not in leukopenic rats. Tissue cell counts revealed a paucity of inflammatory cells in the infarct margins in leukopenic rats. Electron microscopic studies revealed greater preservation of collagen in the 24-hour-old infarcts of irradiated leukopenic rats compared with those of control rats. These results suggest that at 24 hours after experimental MI in the rat, there is significant collagen degradation mediated by inflammatory cell proteases.

Noninvasive evaluation of a left ventricular pseudoaneurysm: complementary role of echocardiographic and nuclear techniques

This 45-year-old white male was evaluated for congestive heart failure initially ascribed to a rapidly progressive cardiomyopathy. Both radionuclide ventriculography and echocardiography correctly identified a left ventricular pseudoaneurysm as the cause for heart failure. Thallium-201 scintigraphy, by demonstrating a large perfusion defect, suggested a large ostium of the pseudoaneurysm. Following resection of the false aneurysm, a Dacron prosthesis was required to close a large posterior wall defect. We conclude that both radionuclide ventriculography and echocardiography can independently demonstrate a left ventricular pseudoaneurysm. The combined noninvasive approach is able to delineate various anatomical aspects of the pseudoaneurysm and help in planning adequate surgical intervention.

Myocardial rupture after myocardial infarction. Detection by multi-gated image-acquisition scintigraphy

Myocardial rupture following infarction usually is an acute and dramatic event. Rarely, it may take a subacute course, allowing surgical treatment. We report herein a case of subacute rupture of the heart in a 54 year old patient with acute myocardial infarction. The rupture was diagnosed by the appearance of a radiopaque halo around the heart during radionuclide ventriculography. The patient subsequently underwent surgical resection of a large anterolateral aneurysm and a 2 inch long rupture of the myocardium and survived. Clinical suspicion, prompt diagnosis, and surgical intervention are important in the management of this relatively unusual complication of infarction.

Myocardial free-wall rupture after acute infarction: survival aided by percutaneous intraaortic balloon counterpulsation

After his first acute myocardial infarction, a 69-year-old male suffered the usually lethal complication of ventricular free-wall rupture. Early suspicion of possible rupture and immediate percutaneous insertion of an intraaortic balloon pump assist device afforded sufficient hemodynamic stability to proceed with cardiac catheterization. The diagnosis of ventricular free-wall rupture was confirmed and the extent of coronary artery disease defined. The patient underwent repair of the free-wall rupture and coronary artery bypass grafting and has returned to full activity.

Long-term survival following cardiac rupture with subsequent development of left ventricular pseudoaneurysm

This report describes a patient who survived rupture of the left ventricular free wall following a myocardial infarction and who then subsequently went on to develop a pseudoaneurysm. The rupture became clinically recognized when the patient developed cardiac tamponade. A large hemopericardium was evacuated by performing a thoracotomy and a pericardiotomy. Although not evident at the time of the initial catheterization, a pseudoaneurysm developed over the ensuing months. The aneurysm was initially recognized by radionuclide angiography and confirmed by left ventricular angiography at a second cardiac catheterization. The aneurysm was successfully resected, and the patient was alive and functioning normally 18 months after rupture and 12 months after aneurysmectomy.