Noninvasive diagnosis of a false left ventricular aneurysm with radioisotope gated cardiac blood pool imaging. Differentiation from true aneurysm

Multimodality Imaging of an Idiopathic Left Ventricular Aneurysm Presenting With Frequent Premature Ventricular Beats

•Apical outpouching in the LV may be due to an aneurysm or pseudoaneurysm. •Multimodality imaging is useful for the evaluation of LV outpouching. •An idiopathic LV aneurysm is a rare condition and is a diagnosis of exclusion. •Asymptomatic small LV aneurysm can be treated conservatively.

Postinfarction left ventricular pseudoaneurysm

Left ventricular wall rupture after myocardial infarction is a mechanical complication that may result in a pseudoaneurysm. Between January 1994 and October 1996, false or pseudoaneurysms were detected in 6 (0.0026%) of 2,600 consecutive patients (4 women, 2 men; mean age 59.4 years) undergoing cardiac catheterization at University Medical School, Debrecen, Hungary. All patients had a history of cardiovascular disease, with diagnosis of pseudoaneurysm confirmed by echocardiography. The average time from the occurrence of acute infarction to diagnosis was 37.0 days (range 3-80 days). All patients were in New York Heart Association functional class IV congestive heart failure; in four patients cardiogenic shock was present. Five patients underwent coronary angiography, which demonstrated multivessel disease and occlusion of the infarct-related artery (TIMIO) without adequate collateral circulation (grade 0-1). Five patients had surgical repair of the false aneurysm, and, in three patients, concomitant coronary bypass grafting was performed. The 2-year mortality rate for all patients was 50%. Early diagnosis of false aneurysm is facilitated by echocardiography, and coronary angiography is required before surgery. Early surgical correction with coronary revascularization is advised.

Distinguishing left ventricular aneurysm from pseudoaneurysm. A review of the literature

A postmyocardial infarction left ventricular pseudoaneurysm occurs when a rupture of the ventricular free wall is contained by overlying, adherent pericardium. A postinfarction aneurysm, in contrast, is caused by scar formation resulting in thinning of the myocardium. Although the usual treatment for patients with pseudoaneurysm is urgent surgical repair, the imaging characteristics of pseudoaneurysm and aneurysm, for which treatment is more conservative, are quite similar. The literature on the natural history and imaging characteristics of the two entities is reviewed, and an approach to distinguishing between the two entities is proposed.

Diagnosis of recurrent left ventricular pseudoaneurysm by echocardiography with color flow imaging

Left ventricular pseudoaneurysms are a rare complication of myocardial rupture. The diagnosis is paramount because of the propensity of pseudoaneurysms to rupture. Color flow imaging has been reported to be an aid in the diagnosis of pseudoaneurysms. We recently studied a patient with a myocardial infarction who developed a left ventricular pseudoaneurysm. Diagnosis was made by two-dimensional imaging with color flow imaging. He subsequently had a repair procedure with a gortex graft. One week after repair, repeat echocardiography with color flow imaging showed flow into the aneurysmal sac at multiple sites, consistent with recurrence of the pseudoaneurysm. Echocardiography with color flow imaging provides a safe noninvasive diagnostic tool for evaluating pseudoaneurysms preoperatively and in assessing the competency of the repair postoperatively.

Cardiac tamponade due to rupture of a subepicardial aneurysm following myocardial infarction

A 71-year-old male died of cardiac tamponade due to cardiac rupture 22 days after onset of acute myocardial infarction. Autopsy revealed rupture of an unusual ventricular aneurysm characterized by abrupt interruption of the myocardium, a narrow neck, a thin fibrous outer wall partially showing myocardial fibers, and lack of adhesion between the epicardium and pericardium. A review of the literature revealed that 11 among 32 autopsy cases of false aneurysm showed a similar morphology to the present case, these being classifiable as subepicardial aneurysm.

Current concepts of left ventricular pseudoaneurysm: pathophysiology, therapy, and diagnostic imaging methods

Left ventricular pseudoaneurysm represents a cardiac rupture which is temporarily confined by pericardium and is amenable to curative surgical treatment. The case described illustrates several atypical features of its presentation and diagnosis, highlighting the importance of maintaining a sufficient clinical index of suspicion for this relatively uncommon, but potentially lethal entity. The use of various diagnostic imaging methods is described, including the first description of magnetic resonance imaging of ventricular pseudoaneurysm. The prospect of medical therapies directed toward the prevention of cardiac rupture, and thus pseudoaneurysm, is discussed in the context of its pathophysiology which involves alterations in the cardiac fibroskeletal support.

Left ventricular pseudoaneurysm after myocardial infarction

As is evident from our case and others, post-myocardial infarction pericarditis with the formation of pericardial adhesions creates a suitable milieu for left ventricular pseudoaneurysm. Although the conditions for pseudoaneurysm formation are rarely met, the clinician should be aware of this diagnosis, even long after myocardial infarction, because of its associated mortality and also because it is surgically curable.

Dissecting intramyocardial hematoma masquerading as a pseudoaneurysm of the left ventricle

This report presents a case of left ventricular intramyocardial dissection masquerading as a ventricular pseudoaneurysm, as documented by echocardiography, magnetic resonance imaging, and angiography with subsequent confirmation at operation.

False aneurysm formation after Salmonella virchow infection of a pre-existent ventricular aneurysm--survival after surgical resection

A 55 year old man with a left ventricular aneurysm, secondary to a previous myocardial infarction, was hospitalized due to a Salmonella virchow bacteraemia. During a 3-week hospital course he was persistently bacteraemic and febrile despite antibiotic treatment. Gallium isotope scanning and 2-D-echocardiography were helpful in demonstrating the presence of an infected false aneurysm at the site of a true aneurysm. Surgical resection in addition to prolonged antibiotic therapy was necessary for cure.

Advantages of colour flow imaging in the diagnosis of left ventricular pseudoaneurysm

Eleven cases of left ventricular pseudoaneurysm in nine patients were studied by cross sectional echocardiography, conventional Doppler echocardiography, and colour flow imaging. In two patients recurrent pseudoaneurysms developed after cardiac surgery, three had acute rupture after myocardial infarction, two were the result of stab wounds, one was a late rupture of a true left ventricular aneurysm, one developed after surgical resection of a true left ventricular aneurysm, and two as a consequence of left ventricular venting. In all 11 cases the diagnosis was confirmed by angiographic or surgical information or both. The diagnosis was suspected clinically in only four cases. Cross sectional echocardiography alone confirmed the diagnosis in five cases. Neither pulsed wave Doppler nor continuous wave Doppler established the diagnosis when they were used without colour flow imaging in five and three cases respectively. In all 11 cases colour flow imaging showed flow in and out of the pericardial cavity at the defect site as well as the abnormal flow within the pseudoaneurysm. Subsequent use of pulsed Doppler showed a consistent "to and fro" flow pattern across the myocardial defect with characteristic respiratory variation of the peak systolic velocity. This unique intrapericardial flow pattern is diagnostic of a pseudoaneurysm. Colour flow imaging is a valuable addition to cross sectional and Doppler echocardiography, and is the best technique for detecting left ventricular pseudoaneurysms.

Color Doppler diagnosis of left ventricular pseudoaneurysm

A patient underwent mitral valve replacement because of mitral insufficiency secondary to bacterial endocarditis. Early postoperatively, routine examination with "color Doppler" correctly identified the presence of a left ventricular pseudoaneurysm. To our knowledge, this is the first case of left ventricular pseudoaneurysm diagnosed by this new technique.

Two-dimensional echocardiographic identification of left ventricular pseudoaneurysm

Nine patients with proved left ventricular pseudoaneurysm after transmural myocardial infarction were studied by two-dimensional echocardiography. In all patients two-dimensional echocardiography successfully displayed the pseudoaneurysm. The unique two-dimensional echocardiographic characteristics of pseudoaneurysm include: a sharp discontinuity of the endocardial image at the site of the pseudoaneurysm communication with the left ventricular cavity, and the presence of a relatively narrow orifice in comparison with the maximum diameter of the pseudoaneurysm fundus; visualization of the maximum diameter of the pseudoaneurysm fundus frequently required a slightly different tomographic view than that required for demonstration of the orifice. The distinctive echocardiographic features of pseudoaneurysm in these patients and technical implications for optimal visualization are described. Most of the pseudoaneurysms we encountered and many of those previously described were located posteriorly. We found the use of inferior angulated view modified from the standard apical four-chamber view extremely helpful in detecting the orifice in patients with posterior or posterolateral pseudoaneurysms. We conclude that two-dimensional echocardiography is an important technique for diagnosis of left ventricular pseudoaneurysm.

An unusual case of postoperative pseudoaneurysm of the left ventricle: Doppler echocardiographic findings

Two years and 9 months after aneurysmectomy of a true left ventricular aneurysm, a 55 year old man presented with clinical features suggestive of acute pericarditis. The echocardiogram revealed a large echo-free space outside the heart. Doppler study showed phasic flow between the echo-free space and the left ventricular cavity through a distinct interruption of the left ventricular apical wall endocardial echoes. The diagnosis of pseudoaneurysm was made and was subsequently confirmed by angiographic and operative findings. After successful repair, a repeat Doppler echocardiographic examination showed a marked reduction in the echo-free space, absence of communication with the left ventricle and no flow signal in the space.

Nuclear medicine in the diagnosis of cardiac contusion

In 16 patients with blunt trauma to the chest, the role of cardiovascular nuclear medicine was evaluated using anterior chest flow assessment, with first-pass ejection fraction of left and right ventricles and 99mTc-pyrophosphate scintigraphy. The radiopharmaceutical used was pyrophosphate, labelled with approximately 20 mCi 99mTc. The anterior chest flow and first-pass ejection fractions were initially obtained during the injection of 99mTc-pyrophosphate and were followed up 3 h later by anterior, LAO 45 degrees, and left lateral views of the chest, using an LFOV gamma camera with a data processor. The results were compared with serial cardiac enzymes studies, electrocardiograms and echocardiograms. Of the patients, 77% showed scintigraphic evidence of cardiac contusion. The intensity of activity varied from grades I to II; five patients had abnormal echocardiographic findings. Only two had abnormal ejection fractions, and one patient had evidence of left ventricular aneurysm along with poor ventricular performance. Cardiac enzymes were found to be the least helpful. Electrocardiograms, though non-specific for myocardial damage, were abnormal in 62% of the patients. Eleven of our patients had both abnormal ECG and increased PYP uptake. Even though there is no agreement as to which noninvasive parameter is more sensitive in the diagnosis of myocardial contusion, 99mTc-pyrophosphate scintigraphy, in conjunction with ECG, seems promising in this respect.

Extracardiac left to right shunt in a patient with biventricular postinfarction rupture and pseudoaneurysm

A 68 year old man had a diaphragmatic myocardial infarction and 9 months later was admitted with severe congestive heart failure (functional class IV). Cardiac catheterization demonstrated a postinfarction pseudoaneurysm. Because of a massive left to right shunt (pulmonary to systemic flow ratio = 2.7), concomitant rupture of the ventricular septum was suspected. At surgery the pseudoaneurysm communicated with the right ventricle through two different orifices and with the left ventricle through another ostium. The ventricular septum was intact. Therefore, the shunt was extracardiac through the pseudoaneurysm (left ventricle----pseudoaneurysm----right ventricle). The unique combination of lesions allowed the patient to survive. The false aneurysm was excised and primary repair was performed in the orifices of the right and left ventricular walls. The postoperative course was uneventful and 10 months later the patient was in functional class I.

Pseudoaneurysm of the left ventricle: diagnosis by gated radioisotope imaging

Because pseudoaneurysms of the left ventricle, although rare, can rupture, their differentiation from true aneurysm is desirable. A case is described in which a pseudoaneurysm was diagnosed noninvasively by means of a gated radioisotope ventriculogram. The diagnosis was made by noting a narrow neck leading to a large chamber. The pseudoaneurysm was successfully excised at surgery.

Subepicardial aneurysms: a rare complication of myocardial infarction

Delayed rupture of myocardial infarcts, more than 10 days after infarction, is only rarely observed at autopsy. Of 1,814 hearts examined after postmortem arteriography from autopsy subjects at the Johns Hopkins Hospital, 704 had 1,140 infarcts. Three (0.2 percent) infarcts were complicated by subepicardial aneurysms, and two of these had ruptured. The infarcts were 21 to 60 days old and had an abrupt dissection of the inferior left ventricular myocardium with a narrow fibrous lined channel comprising the mouth and neck of the aneurysm. The components of the aneurysm wall differed in all three cases. In two, epicardium prevented acute ventricular rupture. In the third case, myocardial fibers were present in the fibrous wall proximally. Adherent parietal pericardium was absent. Previous authors have required the lack of myocardium within the wall to define those lesions, often called pseudoaneurysms. Aneurysms with myocardium have been labeled true aneurysms or pseudo-false aneurysms. A more unifying concept of this lesion is proposed. The unique constellation of features consisting of an abrupt interruption of the myocardium, a narrow neck, and a propensity to rupture spontaneously distinguishes the subepicardial aneurysm regardless of its wall's components. The ability to surgically correct the potentially lethal subepicardial aneurysms necessitates a more accurate categorization of and familiarity with the lesion.

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.

Role of cardiovascular nuclear medicine in evaluating trauma and the postoperative patient

In the patient with cardiac trauma, radionuclide imaging may provide important information about cardiac mechanical function, vascular anatomy and integrity, myocardial perfusion, and myocardial metabolism. Studies require only minimal patient cooperation, can be performed relatively rapidly and often at the bedside, and may be repeated at frequent intervals for serial evaluations. These studies provide valuable adjunctive knowledge when selected and interpreted with knowledge of the mechanism of injury, timing of the examination relative to the time of injury, and most likely differential diagnoses.

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.

Surgical treatment of false aneurysm of the left ventricle after myocardial infarction

Rupture of the left ventricle after myocardial infarction results either in sudden death from cardiac tamponade or, when pericardial adhesions are present, in bleeding that is confined to a limited space, which gradually expands as the blood flows through a small communicating orifice under high pressure, forming a false aneurysm. In three such patients a false aneurysm of the left ventricle after myocardial infarction was successfully treated by operation. The interval from the initiating event to the time of surgery averaged 10 months. Two of the patients had pericarditis and all presented at some stage of the illness with tachyarrhythmias and cardiac failure. All the patients survived operation and have improved functionally. Because of the propensity of false aneurysms to rupture, early diagnosis and aggressive surgical treatment are recommended.

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.

Monitoring cardiac function with nuclear techniques

Noninvasive imaging with radioactive tracers has become widely used since its introduction in the early 1970s. Improvements continue to be made in the techniques and the clinical applications. Much of the information provided by these techniques is new. The first transit studies are used mainly in the evaluation of pulmonary transit time, detection of intracardiac shunting, evaluation of right ventricular function, measurement of ejection fraction and detection of wall motion abnormalities at rest and after exercise. The gated blood pool study is found to be most useful in assessment of global left ventricular function, regional wall motion, valve regurgitation and right ventricular function. The techniques of nuclear cardiac imaging are noninvasive, simple, successfully performed in almost 100 percent of cases. They are easy to interpret, able to be quantified and able to be almost totally automated. Their use is likely to become more widespread in the future.

Scintigraphic evaluation of left ventricular aneurysm

Gated cardiac blood pool scintigraphy is a noninvasive method to assess regional and global left ventricular function in the patient with suspected true or false left ventricular aneurysm after a myocardial infarction. The procedure is easy to perform and provides reproducible, high resolution images that can accurately distinguish from diffuse contractile abnormalities often present after myocardial infarction. An overall accuracy rate of 96 percent for detection of left ventricular aneurysm can be obtained with gated cardiac blood pool scintigraphy as compared with contrast left ventriculography. The procedure also permits assessment of functional reserve of the noninvolved myocardium and thus can provide valuable information on whether enough viable myocardium will remain after aneurysmectomy. The addition of thallium-201 myocardial perfusion scintigraphy may aid in the separation of viable from scarred myocardium at the edge of the aneurysm. Both radionuclide techniques are well suited for screening the patient after infarction with persistent congestive heart failure, malignant arrhythmia or systemic emboli in whom a left ventricular aneurysm may have developed.

Left ventricular diverticulum. A scintigraphic diagnosis

This report describes the scintigraphic features of a congenital left ventricular diverticulum in a child. The types of congenital diverticula of the heart and the possible diagnostic role of nuclear imaging is discussed.

Two-dimensional echocardiographic recognition of left ventricular pseudoaneurysm

Five consecutive patients with proved left ventricular pseudoaneurysm (PA) and 22 patients with true aneurysm (TA) were studied by two-dimensional echocardiography (2DE). In four of the five patients with PA, 2DE successfully displayed the PA. The unique 2DE characteristics of PA include: (1) a sharp discontinuity of the endocardial image at the site of the PA communication with the left ventricular cavity; (2) a saccular or globular contour of the PA chamber; and (3) the presence of a relatively narrow orifice in comparison with the diameter of the PA fundus. In addition, 2DE detected the presence of thrombotic material within the extraventricular chamber in three of four cases. By deriving the ratios of the end-systolic orifice to diameter measurements for the patients with PA (0.37 +/- 0.07) compared with TA (1.00 +/- 0.08), we found that 2DE reliably differentiated PA from TA (p < 0.001). We conclude that 2DE is a useful noninvasive method for revealing left ventricular PAs and for distinguishing PA from TA. Considering the high risk of spontaneous rupture associated with pseudoaneurysms, this noninvasive capability is of paramount clinical importance.

Ventricular aneurysm: false or True? An important distinction

A case of ventricular false aneurysm withe the typical clinical, radiological, electrocardiographic, and angiographic features of this entity is presented. The distinction between false ventricular aneurysm and true aneurysm is discussed. This distinction is important because of the propensity of false aneurysms to rupture. An early diastolic murmur was present prior to, but not after, resection of the aneurysmal sac. A theory as to the origin of this murmur is offered.

Pseudoaneurysm of the left ventricle complicated by Salmonella typhimurium infection. Recognition by two-dimensional echocardiography

A patient is described with a large posterior left ventricular pseudoaneurysm complicated by Salmonella typhimurium infection. M-mode echocardiography displayed a massive echo-free space behind the posterior left ventricular wall, and two-dimensional echocardiography specifically defined the orifice and saccular contour of the false aneurysm. These findings were confirmed by cardiac catheterization and surgery. The unusual features of Salmonella endovascular infection and the noninvasive methods to detect left ventricular pseudoaneurysms are reviewed.

Radionuclide evaluation of cardiac trauma

Radionuclides were first used in the evaluation of myocardial trauma as a noninvasive means to detect hemopericardium. At present an important use is in the diagnosis of myocardial contusion, which can be difficult to recognize clinically, and often has nonspecific EKG and enzyme alterations. Technetium-99m pyrophosphate scintigraphy has been shown to be of significant value in confirming this diagnosis. Myocardial scintigrams are helpful in determining the degree of damage produced by penetrating wounds of the heart and can also detect electrical injury to the heart from accidental shock or cardioversion. In addition, multiple gated blood pool scans can determine the hemodynamic significance of mycardial trauma and evaluate for late sequelae such as aneurysm formation.

Non-invasive diagnosis of a false left ventricular aneurysm by echocardiography and pulsed Doppler echocardiography

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Radionuclide wall motion study and ejection fraction in clinical practice

Assessment of ventricular function is important in diagnosis and as a predictor of survival in many cardiopulmonary disorders, and analysis of ventricular function is one of the oldest applications of radioactive tracers in medicine. A sequence of parallel developments in instrumentation, radiopharmaceuticals, and nuclear medicine computers has allowed implementation of accurate, sensitive, noninvasive techniques for analysis of both right and left ventricular function. Techniques, indications, applications, and information that can be obtained are discussed.

Noninvasive diagnosis of left ventricular pseudoaneurysm: role of two dimensional echocardiography and radionuclide gated pool imaging

This report describes a case of left ventricular pseudoaneurysm diagnosed with two dimensional real time echocardiography. The two dimensional echocardiogram identified not only the pseudoaneurysmal sac but also the site of left ventricular rupture. When supplemented with radioisotope gated cardiac blood pool scanning, the noninvasive studies demonstrated combined true and false left ventricular aneurysms. Left ventricular pseudoaneurysm can be diagnosed using two dimensional echocardiography and nuclear imaging, permitting early operative intervention before fatal rupture.

Left ventricular false aneurysm after coronary bypass surgery: radionuclide diagnosis and surgical resection

A patient with left ventricular pseudoaneurysm formation resulting from myocardial infarction 4 years after coronary bypass surgery is described. The pseudoaneurysm was diagnosed with gated cardiac blood pool imaging and was subsequently successfully surgically repaired. Postoperative pericardial abnormalities predisposing to the possible development of a false aneurysm are discussed. Also, clinical situations in which pseudoaneurysm should be suspected are described, and appropriate diagnostic approaches are outlined.

Non-invasive diagnosis of pseudoaneurysm of left ventricle

A patient free of symptoms, with a pseudoaneurysm of the left ventricle after inferoposterolateral myocardial infarction, is reported. The diagnosis was established by nuclear cardiography and echocardiography of the left ventricle.