Right ventricular mural thrombus caused by myocardial infarction diagnosed by computed tomography

Thrombi of the left ventricle are common sequelae to acute anterior myocardial infarctions that involve the apex of the heart and produce akinetic or dyskinetic wall thickening patterns. While infarctions of the right ventricle are being increasingly recognized in the setting of inferior myocardial infarcts, little data on in vivo clot formation in the right ventricle of the heart are available in these patients. In the current study we were able to demonstrate a right ventricular mural thrombus using gated computed tomography of the heart. Although an abnormality in the right ventricle extending from the septal margin of the ventricle into the outflow tract could be identified with standard blood pool computed tomographic images and from cross sectional echocardiograms, only with cardiac gating could the relationship between the mass (thrombus) and the noncontractile section of the right ventricular myocardium be clearly identified. We conclude that cardiac gating may help in the evaluation of cardiac masses, and in particular cardiac thrombi. This will be particular valuable in the setting of recent or remote infarction, as the relationship between wall-motion abnormalities and thrombus formation has been well documented.     

Visualization of right atrial thrombus associated with constrictive pericarditis by indium-111 oxine platelet imaging

A right atrial thrombus is not often seen and only a few reports of visualization have been described. We report a 44-yr-old man who had a large atrial thrombus associated with constrictive pericarditis. Two-dimensional echocardiography and computed tomography showed a large right atrial mass. Indium-111 oxine platelet deposition was demonstrated on the surface of thrombus by platelet imaging. Platelet imaging was useful for differential diagnosis from cardiac tumor, and as an indication for surgical treatment, since right atrial thrombus may have a high risk of pulmonary embolism or severe right heart failure.     

Various findings of cardiac thrombi on MDCT and MRI

Cardiac thrombus accompanies risk for peripheral embolization, either into the systemic circulation (from the left heart) or into the pulmonary arteries (right heart). In fact, the presence of peripheral emboli should prompt the search for a source within the heart. Echocardiography is the present technique of choice. Also, computed tomography and magnetic resonance imaging may provide additional information. In this article, we will demonstrate various features of cardiac thrombus on computed tomography and magnetic resonance imaging such as mural thrombus after myocardial infarction, thrombus at left atrial appendage in patients with mitral stenosis, thrombus mimicking tumor, organized thrombus containing calcification at left atrium, and compact moderator band mimicking thrombus.     

Pulmonary embolism, right ventricular strain, and intracardiac thrombus-in-transit: Evaluation using comprehensive cardiothoracic computed tomography

A 67-year-old woman presented with symptoms of exertional chest discomfort and dyspnea that had been progressive over the past few days. Her initial evaluation was significant of a mildly elevated troponin-T level and T-wave inversion in leads V₁-V₂ on an electrocardiogram (ECG). Initial suspicion was for acute coronary syndrome. However, a transthoracic echocardiogram showed normal left ventricular systolic function, moderate right ventricular enlargement with moderate decrease in systolic function, possible left atrial mass or thrombus, and a possible right atrial mass or thrombus versus a prominent Chiari network. ECG-gated comprehensive cardiothoracic computed tomography (CT) with a 64-slice multidetector CT was done to assess for pulmonary embolism or acute coronary syndrome and to further evaluate the possible right and left atrial masses. This showed large bilateral pulmonary embolism, interatrial thrombus in transit through a patent foramen ovale, and minimal coronary atherosclerosis. Dynamic imaging showed right ventricular enlargement with severe systolic dysfunction. The patient underwent successful pulmonary thromboembolectomy, removal of intracardiac thrombus, and closure of patent foramen ovale.     

超声检查在急性肺栓塞诊断中的应用价值

目的 探讨超声检查在急性肺栓塞诊断中的应用价值。方法 对临床综合诊断为急性肺栓塞的15例病人行超声心动图检查，综合分析。结果 经超声心动图检查15例患者，发现右房内血栓1例，肺动脉内血栓1例。15例均有右心负荷过重表现，伴有不同程度的三尖瓣返流，返流速度加快，肺动脉压明显增高。7例发现下肢深静脉内血栓。结论 超声心动图在肺动脉栓塞病人的筛查、评价患者的右心功能及疗效方面有重要价值。     

Radionuclide determination of right- and left-ventricular mixing

Previous models for the dynamics of the transit of the bolus of activity of labeled red cells through the chambers of the heart have assumed the complete and instantaneous mixing of tracer with the cardiac blood pool. This assumption can be conveniently tested with a radionuclide procedure. We present a model of the bolus transit through the right and left ventricle that allows the quantitation of the mixing of labeled cells with the residual blood of the cardiac chambers. This model was used to analyze the time-activity curves obtained from a variety of patients undergoing first-pass dynamic scans of the heart. It is shown that technetium-labeled red blood cells and technetium pertechnetate have indistinguishable mixing properties, and the blood in the left ventricle is more thoroughly mixed than that in the right ventricle.     

Radionuclide determination of right- and left-ventricular mixing

Previous models for the dynamics of the transit of the bolus of activity of labeled red cells through the chambers of the heart have assumed the complete and instantaneous mixing of tracer with the cardiac blood pool. This assumption can be conveniently tested with a radionuclide procedure. We present a model of the bolus transit through the right and left ventricle that allows the quantitation of the mixing of labeled cells with the residual blood of the cardiac chambers. This model was used to analyze the time-activity curves obtained from a variety of patients undergoing first-pass dynamic scans of the heart. It is shown that technetium-labeled red blood cells and technetium pertechnetate have indistinguishable mixing properties, and the blood in the left ventricle is more thoroughly mixed than that in the right ventricle.     

Sudden cardiac death associates with a large right atrium thrombus in a late survivor of heart transplantation

A fatal circulatory collapse developed acutely in a patient six years after orthotopic heart transplantation. Autopsy revealed a large, fresh thrombus inside the right atrium which obstructed the orifice of the vena cava completely. The grafted coronary artery and pulmonary vessels were patent. There was no rejection or acute infarct in myocardium. Mildly immature organization was seen on the thrombus-adhered wall. Four chamber enlargement and a rapid decline of right ventricular hypokinesia were detected shortly before death although he did not show active cardiopulmonary symptom. Intracardiac thrombus formation is rather uncommon in late survivor. A synergic effect of atrial turbulence and ventricular hypokinesia in the right heart, superimposed by tissue organization, was proposed for thrombus formation. An empty cardiac output was favored for his mortality. These findings provide a strong evidence to suggest anticoagulation in case of complicated or highly risk of embolization such as turbulence or hypokinesia despite of an absence of active cardiopulmonary symptom.     

A giant tumor thrombus in the right atrium clearly detected by 111In-oxine labeled platelet scintigraphy

A 54-year-old man was admitted to hospital with a 3-month history of progressive dyspnea with coughing. A giant right atrial mass, originating from a hepatocellular carcinoma, was visualized by computed tomography, and digital subtraction angiography. The volume of the right atrial mass was increasing rapidly. It was therefore essential to determine whether this giant mass was a tumor thrombus or a multiplication of the hepatocellular carcinoma. 111In-oxine labeled platelet scintigraphy revealed active accumulation in the right atrium caused by the presence of active platelet deposition, and slight accumulation in the lung fields probably due to embolic showers originating from the tumor thrombus in the right atrium. This is the first case report showing that 111In-oxine labeled platelet scintigraphy can aid in confirming the nature of a giant tumor thrombus in the right atrium and can clarify the pathogenesis of the respiratory symptoms.     

Timing of exposure in angiographic computed tomography

Visualization of heart chambers or the abdominal arterial phase on one of two CT-scans was achieved in 89.4% of 169 injections (91 patients) using only 30 ml of contrast medium (370 mg iodine/ml), when the start of scanning was accurately timed at predicted bolus peak concentration. Normal arrival times and numer of transit cycles to the bolus concentration maximum in the right (RV) and left ventricle (LV) after injection of a small radionuclide bolus of technetium-99 m were related to the patient's heart rate (HR) in a group of 200 patients. For the RV, mean arrival times varied significantly between 2.31 (HR: 90–109 beats per minute) and 3.46 seconds (HR: 50–59 beats per minute), mean number of transit cycles between 4.1 and 3.5. For the LV, mean arrival times varied significantly between 6.92 (HR: 90–109 beats per minute) and 11.37 seconds (HR: 50–59 beats per minute), and the mean number of transit cycles between 11.5 and 10.7. Washout from the LV lasted between an average of 9.2 (HR: 90–109 beats per minute) and 8.5 cycles (HR: 50–59 beats per minute). Contrary to actual transit times, there was no significant difference in the number of transit heart cycles for heart rates between 60 and 109 beats per minute, so that to determine the scan starting time, the patient's cycle length (60 divided by heart rate) had only to be multiplied by the corresponding normal value of transit cycles, i.e., four for the RV, 11 for the LV, and 13 for the abdominal arteries. By applying the estimated values, the result was negative on two successive scans in only 10.6% because of failure in coordination on the part of the operators or bolus transit delays (due to severe heart failure, severe lung disease, recent thoracotomy, or small veins disease). With automatic triggering of the scanner by a timer and injector and with a flush of saline after injection, results can be further improved. Radionuclide studies supported by grant of the Internal Department of the Government of the Federal Republic of Germany     

A giant tumor thrombus in the right atrium clearly detected by 111In-oxine labeled platelet scintigraphy

A 54-year-old man was admitted to hospital with a 3-month history of progressive dyspnea with coughing. A giant right atrial mass, originating from a hepatocellular carcinoma, was visualized by computed tomography, and digital subtration angiography. The volume of the right atrial mass was increasing rapidly. It was therefore essential to determine whether this giant mass was a tumor thrombus or a multiplication of the hepatocellular carcinoma. ¹¹¹In-oxine labeled platelet scintigraphy revealed active accumulation in the right atrium caused by the presence of active platelet deposition, and slight accumulation in the lung fields probably due to embolic showers originating from the tumor thrombus in the right atrium. This is the first case report showing that ¹¹¹In-oxine labeled platelet scintigraphy can aid in confirming the nature of a giant tumor thrombus in the right atrium and can clarify the pathogenesis of the respiratory symptoms.     

Heart failure: evaluation of cardiopulmonary transit times with time-resolved MR angiography

PURPOSE: To measure cardiopulmonary transit times in patients with heart failure by using low-dose, time-resolved magnetic resonance (MR) angiography and to determine if transit curves reflect conventional MR indexes of cardiac function. MATERIALS AND METHODS: Twenty-six patients with heart failure and left ventricular (LV) systolic dysfunction (17 men and nine women; age range, 22-78 years) and thirteen control subjects (eight men and five women; age range, 23-59 years) were examined with MR imaging. The examination consisted of rapid cine MR imaging throughout the heart, followed by contrast material-enhanced time-resolved three-dimensional MR angiography of the cardiac chambers and pulmonary vasculature. Time-intensity curves for the pulmonary artery and ascending aorta were derived from the MR angiography images. Cardiopulmonary transit times and dispersions (full widths at half maximum [FWHM]) were determined from the curves. Transit times and FWHM values for the patients with heart failure were compared with control values by using two-tailed t tests, and transit time was correlated with standard LV functional parameters calculated from the cine MR images. RESULTS: Cardiopulmonary transit times and FWHM values were significantly prolonged in the patients with heart failure compared with those in the control patients (P <.001). Transit time correlated directly with LV end-diastolic and end-systolic volumes and inversely with LV ejection fraction (R > 0.60). However, transit time did not correlate strongly with age, body surface area, heart rate, LV mass, stroke volume, cardiac output, or sphericity index. CONCLUSION: Time-resolved MR angiography allows determination of cardiopulmonary transit times that are significantly prolonged in heart failure and correlate directly with LV volumes and inversely with LV ejection fraction.     

A large intra-atrial thrombus detected during a lung perfusion scan with technetium-99m macroaggregated albumin injected through the subclavian venous line

A sixty five year old female patient carrying a double lumen subclavian catheter, with severe right-sided heart failure, was subjected to lung perfusion scan in order to rule out pulmonary embolism. Administration of Tc-99m macroaggregate albumin ((99m)Tc-MAA), via a double lumen (Hickman) subclavian line, resulted in trapping almost half of the injected dose in the right atrium, at the tip of the subclavian catheter. There was no evidence of pulmonary embolism. This finding was interpreted as consistent with the presence of a large intra-atrial thrombus. This thrombus, despite the thrombolytic treatment that followed, was detached and caused cardiac arrest and eventually the death of the patient. Autopsy showed a massive pulmonary embolus. This report suggests, that injecting (99m)Tc-MAA for a lung perfusion study via the central venous line, may result in the early detection of a thrombus, as in this case at the tip of the catheter and this may be life saving for the patient. We have been unable to find in the literature a similar case of a thrombus detected by the iv administration of (99m)Tc-MAA.     

Identification of intracardiac thrombus: comparison of computed tomography and cross-sectional echocardiography

Thirty-eight patients with conditions predisposing to intracardiac thrombus have been studied by computed tomography and cross-sectional echocardiography. Computed tomography identified 22 cases of intracardiac thrombus (13 left ventricular, eight left atrial and one right atrial). Cross-sectional echocardiography identified five of these left ventricular thrombi and the right atrial thrombus, but none of the left atrial thrombi. In addition, measurements of thrombus density on computed tomography identified a significant difference (p less than 0.02) between the density of a new compared with an organized thrombus.     

永久性和临时性腔静脉过滤器在辅助治疗静脉血栓中的作用

目的探讨腔静脉滤器置入在外周静脉血栓患者溶栓治疗中预防异位栓塞的应用价值.材料和方法7例下肢静脉血栓及1例永存动脉干合并右颈内静脉血栓的患者,分别经静脉置入永久性腔静脉滤器或临时性腔静脉滤器后,用大量尿激酶顺行或全身静脉溶栓治疗.结果8例患者经10～15天治疗后症状消失,血栓完全或部分溶解,血管开通,未出现并发症及异位栓塞.结论置入腔静脉滤器在外周静脉血栓患者溶栓治疗中是预防静脉血栓脱落导致异位栓塞的有效方法.     

Thrombus load and acute right ventricular failure in pulmonary embolism: correlation and demonstration of a “tipping point” on CT pulmonary angiography

Objectives

The aim of this study was to determine the correlation between increasing pulmonary embolism thrombus load and right ventricular (RV) dilatation as demonstrated by CT pulmonary angiography (CTPA) and to assess the thrombus load threshold which indicates impending RV decompensation.

Methods

2425 consecutive CTPAs were retrospectively analysed. Thrombus load using a modified Miller score (MMS), RV to left ventricular (RV:LV) ratio, presence of septal shift, and pulmonary artery and aorta size were analysed in 504 positive CTPA scans and a representative cohort of 100 negative scans. Results were correlated using non-parametric analysis (two-tailed t-test or χ² test) and Pearson’s rank correlation.

Results

Increasing thrombus load correlated with a higher RV:LV ratio, with a statistically significant difference in RV:LV ratios between the negative and positive pulmonary embolism (PE) cohorts. Larger thrombus loads (MMS ≥12 vs MMS <12) were strongly correlated with RV strain (mean RV:LV ratio, 1.323 vs 0.930; p<0.0001). Smaller thrombus loads had no significant influence on RV strain. Septal shift was also more likely with an MMS of ≥12, as was an increase in pulmonary artery diameter (r=0.221, p<0.001).

Conclusion

With increasing thrombus load in PE, there is CTPA evidence of RV decompensation with an MMS threshold of 12. This suggests a “tipping point” beyond which RV decompensation is more likely to occur. This is the first study to describe this tipping point between a thrombus load of MMS >12 and an increase in RV:LV ratio. This finding may help to improve risk stratification in patients with acute PE diagnosed by CTPA.Acute pulmonary embolism (PE) remains a diagnostic challenge for physicians and accounts for significant morbidity and mortality in hospitalised patients. In the United Kingdom, the incidence of proven PE is 60–70 per 100 000 in the population and mortality rates range from 6% to 15%. Clinical manifestations vary widely, from asymptomatic patients with small peripheral emboli to patients who present with circulatory collapse and large thromboembolic loads who may warrant thrombolysis. Between these extremes, there is a significant group presenting with PE who have apparent clinical haemodynamic stability but demonstrate radiological findings (e.g. via echocardiography or CT pulmonary angiography) or biomarkers [such as B-type natriuretic peptide (BNP) or troponin] of right heart strain, in whom the prognosis may be poorer and for whom the role of thrombolysis has not been established [1-4]. Studies to date have demonstrated that right heart strain is associated with higher mortality than no right heart strain [5,6], and CT assessment of right heart strain correlates with echocardiographic findings [7].CT pulmonary angiography (CTPA) has been established as the imaging modality of choice for the initial diagnosis of pulmonary thromboembolism [8,9], and is also used for assessing right ventricular (RV) afterload [10,11]. In addition, it enables quantification of thrombus load, for which a variety of scoring systems are available. These include the modified Miller score (MMS), a catheter pulmonary angiography score [12] adapted for CTPA by Bankier et al [13], and more complex systems such as the Qanadli and Mastora scores [14,15]. The aim of this study was to determine if there is a correlation between increasing thrombus load using MMS and RV dilatation as a predictor of RV failure according to CTPA findings.     

Confirmation by spiral CT of a partially occlusive thrombus of the right pulmonary artery suggested by a V/Q lung scan

Findings on perfusion and ventilation imaging in a 24-year-old woman with anterior chest pain were consistent with pulmonary embolism involving the right lung. An astute physician raised the possibility of a thrombus occluding the right pulmonary artery, and subsequent spiral computed tomography confirmed the suspicion of an occluding thrombus at that site. Had spiral computed tomography been done first, the diagnosis would have been made much more rapidly.     

CT of intracardiac and intrapericardial masses

Computed tomographic (CT) equipment capable of high-resolution, rapid-sequence scanning allows detection of intracardiac and intrapericardial masses. Two patients with intrapericardial masses (pheochromocytoma, organized hematoma) and three patients with intracardiac masses (right ventricular rhabdomyosarcoma, right atrial metastasis, and left atrial thrombus) are presented. CT is the imaging method of choice for displaying pericardial masses directly and may be superior to echocardiography and angiocardiography in the detection of ventricular thrombi. In patients with cardiac tumors, CT evaluates extent of disease including invasion of contiguous vessels and pulmonary metastases better than echocardiography. Dynamic scanning after bolus intravenous injection of contrast material is recommended for the evaluation of patients with suspected masses involving the heart or pericardium.     

原发性肝癌合并下腔静脉-右心房癌栓17例介入治疗体会

目的 评价TACE治疗原发性肝癌合并下腔静脉(IVC)-右心房(RA)癌栓的安全性和临床疗效.方法 17例原发性肝癌合并IVC-RA癌栓患者,行选择性动脉造影确认肿瘤供血动脉,之后行TACE.栓塞材料包括化疗药物-碘化油混合乳剂及颗粒型栓塞材料,栓塞的靶血管包括肝动脉分支、右侧膈下动脉、胃左动脉分支等.术后定期随访,酌情行进一步治疗.结果 17例患者共行TACE治疗45次,所有治疗均成功,无明显并发症.17例患者IVC-RA癌栓均可见明确供血动脉,肝动脉分支供血12例,肝外动脉供血9例,其中胃左动脉1例,右侧膈下动脉8例.复查CT,15例患者可见IVC-RA癌栓内碘油沉积.17例患者的中位生存期为12个月,1、2年生存率分别为52.9％、29.4％.结论 原发性肝癌IVC-RA癌栓血供丰富,主要供血动脉包括肝动脉、右侧膈下动脉,TACE是治疗原发性肝癌合并IVC-RA癌栓的安全有效方法.     

Postpneumonectomy pulmonary artery stump thrombosis: CT features and imaging follow-up

PURPOSE: To retrospectively evaluate the computed tomographic (CT) features of pulmonary artery stump thrombosis at initial and follow-up CT. MATERIALS AND METHODS: The study was approved by institutional review board, which waived informed consent, and was HIPPA compliant. All patients who had undergone pneumonectomy and CT from January 2001 to August 2003, as identified with data search system, were included. Eighty-nine patients (49 men, 40 women; mean age, 60 years) were studied. Thrombus identification, categorization (concave or convex), and stump and thrombus measurements were made by two radiologists in consensus. The use of anticoagulation therapy was determined from patients' charts. The t test was used. RESULTS: Initial CT scans were obtained 34 months +/- 67 (standard deviation) after pneumonectomy; multiple CT scans were obtained in 58 patients during follow-up of 25.1 months +/- 24.8. Eleven (12.4%) of 89 patients had stump thrombi with near equal frequency on either side. Five concave and six convex thrombi were initially identified. Anticoagulation was not commenced for stump thrombosis. The mean length of the right stump (31 mm +/- 10) was greater than that of the left stump (13 mm +/- 7) (P < .01). After a right and left pneumonectomy, there was a significant difference between the length of the stump in patients with (right, 40 mm +/- 14; left, 21 mm +/- 11) and patients without thrombosis (right, 30 mm +/- 9; left, 12 mm +/- 6) (P = .027 and P < .01, respectively). Follow-up CT scans were not available in four cases. CT findings demonstrated a reduction in thrombus size in four patients (one received anticoagulation therapy for concomitant pulmonary embolism). Two patients had stable concave thrombi, one with an initial concave thrombus developed convex thrombus, and one with an initial convex thrombus developed concave thrombus. No thrombi propagated outside of the stump. CONCLUSION: There is a relationship between stump length and the development of in situ thrombosis. The data suggest a rather benign natural history.