Jeffrey M. Silverman

Three-dimensional, time-resolved (4D) relative pressure mapping using magnetic resonance imaging.

We describe here a method for generating relative pressure maps from magnetic resonance velocity data in three spatial and one temporal dimension (4D). The relative pressure map calculated for pulsatile flow in a compliant phantom was shown to be consistent with independent pressure transducer measurements. The feasibility of performing 4D pressure mapping in vivo is also demonstrated. J. Magn. Reson. Imaging 2000;12:321–329.

Atrial emptying with orthotopic heart transplantation using bicaval and pulmonary venous anastomoses: A magnetic resonance imaging study

OBJECTIVES We hypothesized that orthotopic heart transplantation with bicaval and pulmonary venous anastomoses preserves atrial contractility. BACKGROUND The standard biatrial anastomotic technique of orthotopic heart transplantation causes impaired function and enlargement of the atria. Cine magnetic resonance imaging (MRI) allows assessment of atrial size and function. METHODS We studied 16 patients who had undergone bicaval (n = 8) or biatrial (n = 8) orthotopic heart transplantation without evidence of rejection and a control group of 6 healthy volunteers. For all three groups, cine MRI was performed by combining coronal and axial gated spin echo and gradient echo cine sequences. Intracardiac volumes were calculated with the Simpson rule. Atrial emptying fraction was defined as the difference between atrial diastolic and systolic volumes, divided by atrial diastolic volume, expressed in percent. All patients had right heart catheterization. RESULTS Right atrial emptying fraction was significantly higher in the bicaval (mean [+/- SD] 37 +/- 9%) than in the biatrial group (22 +/- 11%, p < 0.05) and similar to that in the control group (48 +/- 4%). Left atrial emptying fraction was significantly higher in the bicaval (30 +/- 5%) than in the biatrial group (15 +/- 4%, p < 0.05) and significantly lower in both transplant groups than in the control group (47 +/- 5%, p < 0.05). The left atrium was larger in the biatrial than in the control group (p < 0.05). Cardiac index, stroke index, heart rate and blood pressure were similar in the transplant groups. CONCLUSIONS Left and right atrial emptying fractions are significantly depressed with the biatrial technique and markedly improved with the bicaval technique of orthotopic heart transplantation. The beneficial effects of the latter technique on atrial function could improve allograft exercise performance.

Phase-contrast cine MR angiography detection of thoracic aortic dissection

Purpose: To assess prospectively the accuracy of phase-contrast cine MR angiography in the detection of thoracic aortic dissection with operative correlation. Materials and methods: One hundred and ninety-seven symptomatic patients suspected of having thoracic aortic dissection or aneurysm as well as 13 patients suspected of having thoracic aortic coarctation and 20 asymptomatic normals (as controls) were examined prospectively with phase-contrast cine MR angiography on a 1.5-T MR imager. Seventy-eight of these patients had operative correlation, and only these 78 patients were included in the statistical analysis. Results: There were 51 true positive and 27 true negative findings of thoracic aortic dissection in this study for an accuracy of 100%. Conclusion: Phase-contrast cine MR angiography is an accurate non-invasive imaging technique for evaluating patients suspected of having thoracic aortic dissection.

Aneurysm of saphenous vein bypass graft detected by first-pass radionuclide ventriculography ☆ ☆☆ ★ ★★

erythrocytes, megakaryocytes, and heart cells. 4 Thus B19 infection could result in anemia, thrombocytopenia, and myocarditis. B19 DNA has been detected in vitro in myocardial cells. 6 Round cell myocardial infiltrates I and intranuclear viral particles typical of B19 have been seen on light and electron microscopic examination, respectively, of fetal cardiac tissue obtained after death. SaintMartin et al.3 recently reported a 1-year-old child with fatal myocarditis associated with serologic evidence of acute B19 infection. B19 DNA was also detected in postmortem myocardial tissue. Ours is the first report of a newborn with cardiomyopathy associated with documented B19 infection. This case also illustrates the relative insensitivity of the anti-B 19 IgM antibody determination for the serodiagnosis of fetal and neonatal B19 infection. 2 In our case, and in others previously reported, 2 viral DNA, but not anti-B19 IgM antibody, was detected in the neonatal period. Dilated cardiomyopathy may be familial or associated with a number of toxins, nutritional deficiencies, carnitine deficiency, ischemia, Kawasaki syndrome, hyperthyroidism and hypothyroidism, and hypoparathyroidism. 7 These causes were all excluded in our patient. Infectious myocarditis, predominantly ascribed to enteroviruses, is the most common putative cause, although many cases remain unexplained. 7 To our knowledge, however, dilated cardiomyopathy associated with B19 infection has not been previously reported in a live-born infant. We speculate that a spectrum of cardiac abnormalities may be associated with intrauterine B 19 infection, in part determined by viral inoculum, fetal gestational age, and immunocompetence. These disease manifestations in the neonate may include, but are not limited to, self-limited or chronic myocarditis, endocardial fibroelastosis, and congenital cardiomyopathy. The prevalence of B19 infection in myocardial disease awaits further investigation.

Case report 659

The only plain radiographic skeletal features in this 71-year-old man were those of a solitary sclerotic lumbar vertebral body which grossly underestimated the extent of metastatic carcinoid involvement of the lumbar spine and elsewhere described in the text. The primary focus in this case was either the pancreas or gallbladder resulting in disseminated metastases to the skeleton and many visceral areas. It was emphasized that these skeletal metastases are principally blastic and that those carcinoids arising in the bronchi and foregut-related structures (e.g., stomach) most often metastasize to the skeleton.