[Cardiac arrest in a fitness trainer with apical hypertrophic cardiomyopathy associated with cor triatriatum sinister]. / Plötzlicher Herztod einer Fitnesstrainerin mit hypertropher Kardiomyopathie vom apikalen Typ assoziiert mit Cor triatriatum sinister.

We report on a 49-year-old fitness trainer, who was admitted to our hospital after cardiac arrest due to ventricular fibrillation. Return of spontaneous circulation was achieved after immediate cardiopulmonary resuscitation. Coronary angiography could exclude coronary artery disease. Echocardiography demonstrated the presence of apical hypertrophic cardiomyopathy, associated with cor triatriatum sinister. Cardiac magnetic resonance imaging additionally showed marked myocardial fibrosis. The patient underwent placement of an implantable cardioverter-defibrillator and was subsequently discharged for rehabilitation in good condition.

[Surgery for congestive heart failure--the role of computed tomography in the pre- and postoperative diagnostic evaluation]. / Chirurgie der Herzinsuffizienz -- Stellenwert der Computertomographie in der prä- und postoperativen Diagnostik.

The treatment of advanced, drug resistant congestive heart failure gains in importance in the field of cardiac surgery. Cardiac imaging for preoperative assessment and follow-up focuses on the determination of ventricular volumes and function as well as on the detection of postoperative complications. Computed tomography (CT) is highly accurate irrespective of the individual patient's anatomic situation, has a low examiner dependence and short examination time, does not require an arterial vascular access and can be performed in patients with metal implants. CT is the modality of choice in the follow-up of heart transplants to detect extracardiac and cardiac complications including coronary calcifications as an early sign of transplant vasculopathy. In addition, CT visualizes the elements of mechanical assist devices and can identify their possible local cardiac and mediastinal complications. CT can detect fibrolipomatous involution of the mobilized muscle flap in dynamic cardiomyoplasty and can depict fibrous reactions along the epicardial mesh implant in passive cardiac containment. Further indications include assessment of typical local postoperative complications, such as intrathoracic infection and mediastinal bleeding, intracardiac thrombus formation or pericardial effusion. CT is routinely used for evaluating bypass patency but is limited in assessing associated valve defects since it does not visualize flow.

The active magnetic resonance imaging stent (AMRIS): initial experimental in vivo results with locally amplified MR angiography and flow measurements.

RATIONALE AND OBJECTIVES: Magnetic resonance (MR) is limited by artifacts in vessels after stenting. An active MR imaging stent (AMRIS) allows for artifact-free imaging with local improvement in signal-to-noise ratio (SNR). In a rabbit model, we evaluated the imaging properties by MR angiography (MRA) and flow measurements. METHODS: The AMRIS was placed in the abdominal aorta of five rabbits. At 1.5 T, MRA (three-dimensional fast low-angle shot) was performed before and after intravenous injection of an iron oxide-based, blood-pool contrast medium (dose, 50 micromol Fe/kg), and flow measurements were performed (electrocardiographically triggered phase-contrast cine gradient-echo sequence). Mean SNRs were calculated and flow volume curves were generated. RESULTS: The SNR was 6.0 +/- 0.6 (outside the stent) versus 12.3 +/- 1.1 (inside the stent, P < 0.05) for plain MRA, 21.2 +/- 0.6 versus 40.6 +/- 5.2 (P < 0.05) for contrast-enhanced MRA, and 5.4 +/- 0.4 versus 13.7 +/- 2.1 (P < 0.05) for the magnitude images of flow measurements. Flow volume curves within and distal to the stent were comparable. CONCLUSIONS: By using the AMRIS as a vascular stent, the stented vessel segment can be examined with enhanced signal intensity on MRI.

Magnetic resonance imaging of stentless xenografts for reconstruction of right ventricular outflow tract.

The objective was to overcome allograft shortage during the Ross operation; stentless xenografts were carefully evaluated for hemodynamic behavior and valve deterioration during medium term follow-up. Between January 10, 1994 and January 4, 1996 nine adult patients (age 31-51 years) underwent aortic valve replacement with an autologous pulmonary valve and right ventricular outflow tract reconstruction with the Edwards Prima or Medtronic Freestyle xenograft. One patient was dead early and one late, both from noncardiac reasons. Forty-eight to 66 months follow-up was available for 7 patients and was performed with physical examination in the outpatient clinic, transthoracic echocardiography (TTE), and magnetic resonance imaging (MRI). Two patients received 29-mm valves and the remaining 27-mm valves. No reoperation became necessary during follow-up. Preoperative left ventricular ejection fraction ranged from 20% to 84%, median 61%, mean 59% +/- 18%. At latest follow-up left ventricular ejection fraction was 49% to 70%, median 57%, mean 58% +/- 8%. TTE showed no calcification of the xenograft wall or cusps. MRI revealed good autograft function with no evidence of stenosis in any patient. Four patients showed no and three trivial regurgitation. Right ventricular outflow tract-stenosis could not be seen in any patient. Calculated gradients of the xenograft valves ranged from 2 to 6 mm Hg, median 3 mm Hg (mean 3.1 +/- 2.4 mm Hg) and calculated EOA ranged from 2.0 to 4.0 cm(2), median 2.8 cm(2). MRI supported these findings and showed pliable xenograft cusps in all patients. Right ventricular function was well preserved in all patients. In adult patients right ventricular outflow tract reconstruction with stentless xenografts can be performed safely and intermediate-term results are encouraging. During medium-term (5-7 years) follow-up no calcification or deterioration of valve function occurred with excellent hemodynamic behavior.

[Diagnostic assessment after myocardial infarction: What is the role of magnetic resonance imaging?]. / Bildgebung nach Myokardinfarkt: Was leistet die Magnetresonanztomographie?

There have been considerable advances in the diagnostic assessment of the heart by magnetic resonance imaging (MRI) in recent years. Thus MRI as a one-stop shop modality for the comprehensive noninvasive evaluation of coronary heart disease and myocardial infarction may soon become a reality. This article presents an overview of the present possibilities and future potential of evaluating myocardial anatomy, function, perfusion, and coronary anatomy after myocardial infarction. Cine MRI provides a reliable analysis of regional and global disturbances of cardiac wall motion with a high temporal and spatial resolution. Tagging techniques permit the noninvasive labelling of parts of the myocardium and the identification of three-dimensional patterns of contraction. Myocardial perfusion and disturbed wall motion under pharmacologic stress can be reliably assessed by MRI as well. What is unique is the visualization of myocardial edema, which is made possible by the high soft-tissue contrast resolution. The as yet limited potential to assess coronary arteries and coronary bypasses is likewise discussed.

[Evaluation of regional wall motion abnormalities of the heart--comparison with doppler tissue echocardiography, MR-tagging and levocardiography]. / Beurteilung regionaler Wandbewegungsstörungen des Herzens--Vergleich von Gewebe-Doppler-Echokardiographie, MR-Tagging und Lävokardiographie.

PURPOSE: To compare the visual analysis of magnetic resonance imaging (MRI) with the tagging technique and Doppler tissue echocardiography with invasive ventriculography in detecting and quantifying regional left ventricular wall motion abnormalities. MATERIALS AND METHODS: Sixteen patients with coronary artery disease and a history of prior myocardial infarction underwent invasive ventriculography, Doppler tissue echocardiography and MR-tagging within one week. Regional wall motion abnormalities (WMA) were detected in all patients. WMA were graded as normal = 1; hypokinetic = 2; akinetic = 3; or dyskinetic = 4. For agreement between MRI, echocardiography, and ventriculography the kappa coefficient (kappa) according to Cohen was calculated. RESULTS: The kappa coefficient (kappa) was 0.962 for agreement between MRI and echocardiography and 0.602 for agreement between MRI and ventriculography as well as between echocardiography and ventriculography. CONCLUSION: Reliable analysis of regional left ventricular wall motion abnormalities is feasible using visual analysis of MR-tagging. MRI and Doppler tissue echocardiography detect more WMA than invasive ventriculography and grade them as more severe.

[Determination of left ventricular function parameters and myocardial mass: comparison of MRI and EBT]. / Bestimmung linksventrikulärer Funktionsparameter und der Myokardmasse: Vergleich von MRT und EBT.

PURPOSE: Comparative volumetric assessment of the left ventricle by magnetic resonance imaging (MRI) and electron beam tomography (EBT) in patients with ischemic and dilated cardiac disease. METHODS: Thirty-two patients underwent cine MRI and EBT in the multislice mode. All studies were triggered to the ECG. Left ventricular ejection fraction (EF), end-diastolic (EDV) and end-systolic volume (ESV), and myocardial mass (MM) were determined by 3D-volumetry by MRI and EBT and results were compared. RESULTS: The correlation between MRI and EBT for EF, EDV, ESV, and MM were r = 0.86, r = 0.95, r = 0.95, and r = 0.93, respectively. CONCLUSIONS: There is an excellent correlation between MRI and EBT in determining left-ventricular parameters. Both methods are suitable for volumetric assessment of the left ventricle.

[Evaluation of passive cardiomyoplasty using left- and right-ventricular volume measurements by EBCT and MRI in patients with chronic congestive heart failure]. / Evaluierung der passiven Kardiomyoplastie mittels links- und rechtsventrikulärer EBCT- und MRT-Volumetrie bei Patienten mit chronischer Herzinsuffizienz.

PURPOSE: To evaluate the efficacy of passive cardiomyoplasty with the determination of biventricular volumes, global systolic function as well as left-ventricular muscle mass. MATERIALS AND METHODS: In 19 patients with congestive heart failure of idiopathic or ischemic origin, a polyester mesh-graft was implanted around both ventricles for stabilization and functional support. Before and three months after surgery, 15 patients underwent EBCT and 4 patients with impaired renal function underwent MRI, for the evaluation of the volume and ejection fraction of both ventricles. RESULTS: EBCT demonstrated a decrease from 385 to 310 ml in LV-EDV, from 312 to 242 ml in LV-ESV, from 209 to 160 ml in RV-EDV and from 149 to 87 ml in RV-ESV, and an increase from 20 to 26% in LV-EF and from 37 to 50% in RV-EF as well as a reduction of LV-MM from 300 to 274 g (p < 0.05 each). Similar results were obtained by MRI. CONCLUSION: Following passive cardiomyoplasty, EBCT and MRI revealed an improvement of the global systolic function as well as a reduction of biventricular volumes and left-ventricular muscle mass.

[MR angiography of the coronary arteries: comparison of the blood pool contrast medium Gadomer and Gd-DTPA in pigs]. / MR-Angiographie der Koronararterien: Vergleich des Blutpoolkontrastmittels Gadomer mit Gd-DTPA am Schwein.

AIM: To investigate the signal-enhancing effects of the macromolecular contrast medium Gadomer in MR angiography of the coronary arteries compared to Gd-DTPA. MATERIAL AND METHODS: A total of 15 MRI examinations of the heart were performed in pigs at 1.5 T using a pulse-triggered, segmented 3D FLASH sequence with data acquisition during breathhold before and up to 30 min after contrast medium injection. Gadomer was investigated at two doses (0.05 and 0.1 mmol Gd/kg), Gd-DTPA at one (0.3 mmol Gd/kg) (n = 5 examinations per dose). Standard sequences without magnetization preparation were supplemented by sequences with magnetization saturation applied before data acquisition before and immediately after contrast medium injection. Analysis comprised quantitative determination of blood and myocardium signal to noise (S/N) and contrast to noise (C/N) and qualitative assessment of several parameters of image quality and coronary artery visualization. RESULTS: Gadomer leads to a significant C/N increase between blood and myocardium compared to the unenhanced examination and the increase is longer-lasting than that produced by Gd-DTPA (Gd-DTPA: only directly after injection; Gadomer: up to 5 min post injection at 0.05 mmol Gd/kg, up to 10 min at 0.1 mmol Gd/kg). The qualitative evaluation shows that visualization of the coronary arteries and branch vessels is significantly better with Gadomer at both doses than with Gd-DTPA. Magnetization saturation increases the C/N in combination with Gd-DTPA and at the higher dose of Gadomer with the latter producing a higher increase in C/N values. CONCLUSION: Gadomer is a suitable contrast medium for MR angiography of the coronary arteries with the dose of 0.1 mmol Gd/kg being superior to 0.05 mmol Gd/kg due to a longer imaging window.

[Left ventricular reduction surgery: pre- and postoperative evaluation by cine MRI]. / Linksventrikuläre Volumen-reduktion: Prä- und postoperative Evaluierung mit der Cine MRT.

AIM: To evaluate the role of cine magnetic resonance imaging (MRI) in the preoperative assessment and postoperative follow-up of patients undergoing left ventricular (LV) reduction surgery. PATIENTS AND METHODS: 6 patients with cardiomegaly were examined on a 1.5 T MR imager before and after LV reduction surgery. The heart was imaged along the short and long axes using a breath-hold ECG-triggered cine gradient-echo sequence for assessing ventricular and valvular morphology and function and performing volumetry (end-diastolic and end-systolic volumes, ejection fraction). RESULTS: Postoperatively, the mean ejection fraction increased from 21.7% to 33.4% and the end-diastolic and end-systolic left ventricular volumes decreased in all patients (304.0 and 252.5 ml before to 205.0 and 141.9 ml after surgery). Mean myocardial mass decreased slightly from 283.8 g to 242.7 g. Differences were significant for all parameters (p < 0.05). MRI allowed for the reliable assessment of post-operative valve morphology and yielded additional findings such as the presence of mitral valve insufficiency or ventricular thrombus. CONCLUSIONS: Cine MRI provides relevant information prior to left ventricular reduction surgery and reliably depicts functional and morphological changes in the early post-operative follow-up.

A post-processing protocol for three-dimensional visualization of the inner ear using the volume-rendering technique based on a standard magnetic resonance imaging protocol.

A superior diagnostic quality compared to other post-processing (PP) techniques for three-dimensional (3D) inner ear imaging has been attributed to volume rendering (VR). We defined and assessed a VR protocol for 3D visualization of the inner ear in a routine imaging setting. Following definition of a VR protocol by using lower threshold values, surface shading, perspective views and related parameters, standardized 3D views of the inner ear were generated and evaluated in 32 patients suffering from sensorineural or combined hearing loss. Comprehensive inner ear visualization was achieved in 28 patients by means of two 3D shaded-surface views. Incomplete data acquisition (1/32), motion and pulsation artefacts (2/32) and interposed fluid-retaining mastoid cells (1/32) were responsible for non-diagnostic image quality in 4/32 patients. In 5/32 patients modifications of the PP protocol involving the threshold value and depth-cueing parameters helped to establish diagnostic image quality. Mean post-processing time amounted to 5.8 min per site. 3D imaging with the VR technique is suitable for routine inner ear assessment if direct VR, predefined PP protocols and standardized labyrinthine views are used.

Value of digital radiography in expiration in detection of pneumothorax.

PURPOSE: The purpose of this study was to find out whether pneumothorax detection and exclusion is superior in expiratory digital chest radiography. MATERIALS AND METHODS: 131 patients with pneumothorax with paired inspiratory and expiratory chest radiographs were analyzed regarding localization and size of pneumothorax. Sensitivity, specificity, negative (npv) and positive predictive value (ppv) as well as the positive (LR+) and negative likelihood ratio (LR-) were determined in a blinded randomized interobserver study with 116 patients. The evaluation was performed by three board-certified radiologists. RESULTS: In 131 patients, there were 139 pneumothoraces, 135 (97.1 %) were located apical, 88 (63.3 %) lateral and 33 (23.7 %) basal. Sensitivity was 99 % for inspiratory and 97 % for expiratory radiographs. The interobserver study yielded a mean sensitivity of 86.1 %/86.1 %, specificity of 97.3 %/93.4 %, npv of 88.7 %/88.5 % and ppv of 96.7 %/92.1 % for inspiration/expiration. For inspiratory radiographs the LR+/LR- were 40.2/0.14 and for expiration 13.9 and 0.15. McNemar-Test showed no significant difference for the detection of pneumothoraces in in-/exspiration. CONCLUSION: Inspiratory and expiratory digital radiographs are equally suitable for pneumothorax detection. Inspiratory radiographs are recommended as the initial examination of choice for pneumothorax detection, an additional expiratory radiograph is only recommended in doubtful cases. KEY POINTS: • Basal pneumothoraces during inspiration demonstrate a greater width than during expiration. • There is statistically no difference between inspiration/expiration for the diagnosis of pneumothorax. • An image taken during inspiration is recommended to confirm or rule out a pneumothorax.

New insights into peripartum cardiomyopathy using cardiac magnetic resonance imaging.

PURPOSE: The aim of this study was to evaluate a comprehensive cardiac magnetic resonance (MR) imaging approach in patients with peripartum cardiomyopathy (PPCM). The focus was on inflammatory myocardial changes. MATERIALS AND METHODS: Retrospective analysis of 12 cardiac MR examinations was performed in 6 patients with PPCM. The protocol comprised cine sequences for the determination of chamber sizes and function. T 2-weighted sequences for determination of edema (T 2 ratio), T 1-weighted images for measurement of early gadolinium enhancement ratio (EGER), and late gadolinium enhancement (LGE) sequences were used for tissue characterization. 5 examinations were performed during the acute stage, and 7 examinations were performed during the course of the disease. RESULTS: Initially, 3 of 5 patients presented with an elevated left ventricular end-diastolic volume (LVEDV); in one patient, the LVEDV was in the upper range. In 4 of 5 subjects, the left ventricular ejection fraction (LVEF) was decreased. The T 2 ratio and EGER values were initially elevated in all women. No LGE was detected in initial scans. In follow-up examinations, the LVEDV decreased and the LVEF increased in all patients. Tissue-characterizing parameters decreased to normal in all but 1 patient. 2 patients showing LGE did not present a favorable clinical course. CONCLUSION: Myocardial inflammation was detected in the acute stage of PPCM, which was mostly transient. In our small group, patients showing LGE had a non-favorable clinical course. Future studies should include tissue-characterizing parameters, such as T 2 ratio and EGER. Thus, further insights into pathophysiology can be gained and therapeutic effects can be measured in a more extensive manner.

[Recommendations of the Heart Diagnosis Working Group of the German Roentgen Society for use of computerized tomography and magnetic resonance tomography in heart diagnosis. 1-- Computerized tomography]. / Empfehlungen der Arbeitsgemeinschaft Herzdiagnostik der Deutschen Röntgengesellschaft für den Einsatz der Computertomografie und Magnetresonanztomografie in der Herzdiagnostik. Teil 1 - Computertomografie.

MRI and CT have become important tools in the diagnosis of cardiac diseases. The permanent technical development and the continuously growing clinical and scientific experience required an update of the previous recommendations regarding the spectrum of clinical applications and the technical aspects of MRI and CT of the heart. The Working group Herzdiagnostik of the German Roentgen Society has revised its recommendations based on the current literature and has updated technical requirements and clinical indications. Part I of the recommendations deals with cardiac computed tomography while part II focuses on MRI in cardiac applications. These recommendations shall serve as a guideline when deciding on appropriate technique for non-invasive cardiac imaging and shall help to perform high quality imaging based on a standardised approach.

[Recommendations for utilizing computerized tomography and magnetic resonance tomography in heart diagnosis. 2--Magnetic resonance tomography ]. / Empfehlungen für den Einsatz der Computertomografie und Magnetresonanztomografie in der Herzdiagnostik. Teil 2 - Magnetresonanztomografie.

MRI and CT have become important tools in the diagnosis of cardiac diseases. The permanent technical development and the continuously growing clinical and scientific experience required an update of the previous recommendations regarding the spectrum of clinical applications and the technical aspects of MRI and CT of the heart. The Working group Herzdiagnostik of the German Roentgen Society has revised its recommendations based on the current literature and has updated technical requirements and clinical indications. Part I of the recommendations deals with cardiac computed tomography while part II focuses on MRI in cardiac applications. These recommendations shall serve as a guideline when deciding on appropriate technique for non-invasive cardiac imaging and shall help to perform high quality imaging based on a standardised approach.

Cine magnetic resonance imaging of the small bowel: comparison of different oral contrast media.

PURPOSE: To evaluate several substances regarding small bowel distension and contrast on balanced steady-state free precession (bSSFP) cine magnetic resonance (MR) images. MATERIAL AND METHODS: Luminal contrast was evaluated in 24 volunteers after oral application of two different contrast agent groups leading to either bright lumen (pineapple, blueberry juice) or dark lumen (tap water, orange juice) on T1-weighted images. Bowel distension was evaluated in 30 patients ingesting either methylcellulose or mannitol solution for limiting intestinal absorption. Fifteen patients with duodeno-jejunal intubation served as the control. Quantitative evaluation included measurement of luminal signal intensities and diameters of four bowel segments, qualitative evaluation assessed luminal contrast and distension on a five-point scale. RESULTS: Quantitative and qualitative evaluation of the four contrast agents revealed no significant differences regarding luminal contrast on bSSFP images. Quantitative evaluation revealed significantly lower (P<0.05) small bowel distension for three out of four segments (qualitative evaluation: two out of four segments) for methylcellulose in comparison to the control. Mannitol was found to be equal to the control. CONCLUSION: Oral ingestion of tap water or orange juice in combination with mannitol is recommended for cine MR imaging of the small bowel regarding luminal contrast and small bowel distension on bSSFP sequences.