94 When the gut affects the heart

A 59-year-old man came to our attention with progressive shortness of breath associated with lower limb oedema. He complained also of recurrent malar flushing, diarrhea and weight loss (14 kg in the last 8 months). At physical examination, a holosystolic murmur best heard over the fourth left sternal border, intensified upon inspiration, and a palpable tender liver with irregular surface were noted.

Transthoracic and transesophageal echocardiogram revealed dilated right chambers. The tricuspid annulus was dilated and the leaflets thickened, shortened and retracted with restricted mobility and incomplete coaptation, leading to severe tricuspid regurgitation (Panels A-B). Moderate pulmonary regurgitation was also detected (Panel C). Cardiac MR confirmed the morphology of the tricuspid valve (Panels D-E, arrows) and the severity of the tricuspid regurgitation (regurgitant fraction 66%). The pulmonary valve leaflets were also thickened and fixed (Panel F, arrow), with moderate pulmonary regurgitation (regurgitant fraction 21%).

With the suspicion of carcinoid syndrome, 5-hydroxyindoleacetic acid (5-HITT) was tested by 24-hour urine sample and a value of 929.5 µmol/24h was found (n.v. 10.5-47.1).

Whole body 18-F DOPA PET was performed. Axial views and reconstructed images revealed a short segment of mural thickening (2.4 cm and 1.1 cm) in the jejunum with a moderate/high uptake (Panels G, arrow). Adjacent to this lesion, a mesenteric spiculated mass (4.0 x 2.8 cm) with moderate uptake was visible (Panels H, arrow). Multiple enhancing nodules with high uptake were present in the liver (Panel I).

One of the liver nodules was biopsied. The biopsy revealed extensive infiltration by well differentiated neuroendocrine tumor (Panel J, blue arrow). The tumor cells were arranged in nests and were composed of cells with round to oval nuclei and eosinophilic cytoplasm (Panel K). The neuroendocrine nature of the tumor was confirmed by strong diffuse positivity with synaptophysin (Panel L), chromogranin and CD 56. Ki-67 showed a proliferative index of less than 3%. The tumor morphology, combined with the immunohistochemical features, was in keeping with a well differentiated neuroendocrine tumor.

Carcinoid heart disease is a rare cause of primary tricuspid and pulmonary valve disease leading to significant morbidity and mortality caused by right heart failure. The characteristic pathological findings are endocardial plaques of fibrous tissue that may involve the tricuspid valve and, rarely, the pulmonary valve. The fibrous tissue in the plaques results in distortion of the valves leading to either stenosis, regurgitation, or both.

Abstract 94 Figure.

A hand-carried cardiac ultrasound device in the outpatient cardiology clinic reduces the need for standard echocardiography

OBJECTIVE

To assess the potential value and cost-effectiveness of a hand-carried ultrasound (HCU) device in an outpatient cardiology clinic.

METHODS

222 consecutive patients were prospectively enrolled in the study. When standard echocardiography (SE) was specifically indicated on the basis of clinical history, electrocardiogram and physical examination, the same cardiologist (level-2 or level-3 trained) immediately performed an HCU examination. The cardiologist then reassessed the clinical situation to confirm or cancel the SE request according to the information provided by HCU. The SE examination was performed by a sonographer and examined in a blinded fashion by a cardiologist expert in echocardiography. Findings from the two examinations were compared.

RESULTS

HCU was performed in 108/222 patients, and a definite diagnosis was established in 34 of them (31%), making SE examination potentially avoidable. In the 74 patients with inconclusive HCU results and for whom SE was still indicated, the decision was mainly dictated by the lack of spectral Doppler modality in the HCU system. The overall agreement between HCU and SE for diagnosis of normal/abnormal echocardiograms was 73% (kappa = 0.4). On the basis of the potentially avoided SE examinations and the obviated need for a second cardiac consultation, a total cost saving of euro2142 per 100 patients referred for echocardiography was estimated.

CONCLUSIONS

The use of a simple HCU device in the outpatient cardiology clinic allowed reliable diagnosis in one third of the patients referred for echocardiography, which translates into cost and time saving benefits.

[Emergency department ultrasonography: impact on patient management and cost effectiveness]

AIM

Ultrasonography is the most common noninvasive method for the evaluation of body organs and systems. However, the feasibility and potential advantages of ultrasound scanning by emergency physicians have not yet been fully explored. We therefore wanted to determine the impact of ultrasound scanning by emergency physicians on patient management in the Emergency Department, length of hospital stay, and related costs.

METHODS

From a data-base search at our hospital we selected 111 patients and divided them into 3 groups according to symptoms: right hypochondriac region pain (Group A), flank pain (Group B), abdominal pain and hemodynamic instability (Group C). Patients were further stratified into 3 subgroups according to whether they were treated by an emergency physician or a radiologist or did not undergo ultrasonography. For each group the mean length of stay in the emergency department, the complications rate, the recurrence rate (defined as return visit to the emergency department for the same pathology) and the related costs were calculated.

RESULTS

Of the 111 patients, 76 received ultrasound scanning, of which 43 were treated by an emergency physician. The length of hospital stay for this group was shorter than that of the other 2 subgroups. The recurrence rate was highest in the group that did not undergo ultrasonography. The costs were lower for the group that received ultrasound scanning by an emergency physician than for the group treated by a radiologist (Euro 20 vs Euro 38).

CONCLUSION

Ultrasound scanning by emergency physicians can shorten length of hospital stay for emergency patients, reduce recurrence rates for the same pathology and lower patient management costs.

Scurvy mimicking systemic vasculitis

An 91 years old woman was hospitalized because of lethargy, shortness of breath and diffuse subcutaneous hemorrhage of legs. Clinical features were consistent with the diagnosis of vasculitis with systemic involvement. However dermatologic characteristics of the legs, in association with malnutrition, suggested vitamin C deficiency which was confirmed by laboratory test. Ascorbic acid supplement dramatically improved her clinical symptoms. This case remarks how scurvy may mimmick a systemic vasculitis.

Two distinct populations of tumor necrosis factor-stimulated gene-6 protein in the extracellular matrix of expanded mouse cumulus cell-oocyte complexes

After the luteinizing hormone surge, the cumulus cell-oocyte complexes (COCs) in the preovulatory follicles produce a viscoelastic extracellular matrix, a process that requires the synthesis of hyaluronan as well as the incorporation of some components of the inter-alpha-trypsin inhibitor (IalphaI) family. In this study we report, that a hyaluronan-binding protein, the translated product of tumor necrosis factor-stimulated gene-6 (TSG-6), is also specifically accumulated in this matrix. TSG-6 mRNA expression is quickly upregulated and peaks at approximately 1500 copies/cell 4 h after the ovulatory stimuli as assessed by quantitative reverse transcription-polymerase chain reaction. Immunohistochemistry reveals the colocalization of the TSG-6 protein and hyaluronan around the cumulus and granulosa cells. The TSG-6 protein exists in two distinct populations in the COC matrix as demonstrated by Western-blot analysis. One population is a monomer that is anchored to the matrix by a noncovalent interaction. The second population is a covalent complex with either of the heavy chains of IalphaI and is bound to hyaluronan through a strong interaction that is resistant to denaturing conditions. The specific incorporation of the TSG-6 protein into the COC matrix suggests a structural role for this molecule.

Effect of early treatment with captopril and metoprolol singly and together on postinfarction left ventricular remodeling

BACKGROUND

beta-Blockers improve clinical outcome after acute myocardial infarction (AMI), but few data are available on their effectiveness in preventing left ventricular remodeling. The aim of the study was to assess the relative effects of captopril, metoprolol, and their combination on left ventricular remodeling after uncomplicated AMI.

METHODS

Two hundred fifty consecutive patients with a first AMI were randomly allocated to receive for 6 months captopril (up to 75 mg/d, group 1), metoprolol (up to 200 mg/d, group 2), or both (group 3) starting within 24 hours from symptom onset. Of these, 130 patients (group 1, 46; group 2, 47; group 3, 37) completed the study; all patients underwent 2-dimensional echocardiography at baseline and after 2 weeks and 3 and 6 months from AMI.

RESULTS

At 6 months, in comparison with baseline values, left ventricular end-diastolic area index (LVEDI) significantly increased in group 3 (P =.013) and wall motion score index significantly decreased in group 1 (P =.038). At any follow-up evaluation, the covariance analysis showed significantly greater interval changes in LVEDI in group 3 than in group 1 (P =.0077 at 2 weeks, P =.0108 at 3 months, and P = 0.0155 at 6 months). No significant differences were observed between group 1 and group 2 and between group 2 and group 3.

CONCLUSIONS

After uncomplicated first AMI, early and long-term treatment with captopril alone attenuates left ventricular remodeling better than its combination with metoprolol. In the head-to-head captopril versus metoprolol therapy strategy comparison, captopril alone seems more effective in reducing postinfarction enlargement, but a definite difference was not demonstrated.

Constrictive pericarditis after cardiac surgery

Constrictive pericarditis is an infrequent complication of cardiac surgery. We report the case of a young woman who developed dyspnea and ascites 3 years after surgical closure of an atrial septal defect, and the findings at chest X-ray, computed tomographic scan and Doppler echocardiography are described. Epidemiology of the disease, new pathophysiologic concepts, diagnostic features, and therapeutic targets are reviewed.

Control of mouse cumulus cell-oocyte complex integrity before and after ovulation: plasminogen activator synthesis and matrix degradation

During the preovulatory period, cumulus cells (CCs) form a hyaluronan-protein extracellular matrix (cumulus expansion) that positively influences oocyte fertilization. Degradation of this matrix and CC-oocyte complex (COC) dissociation occurs within a few hours of ovulation and parallels the aging of oocytes. Modulation of CC proteolytic activity by gonadotropins and oocyte soluble factors has been hypothesized to determine such cumulus matrix changes. In the present study, we investigated plasminogen activator (PA) synthesis by COCs during the expansion and disassembly processes. Our results show that the secretion of tissue type PA and urokinase type PA (uPA) by oocytes and CCs, respectively, does not change significantly during expansion but dramatically increases thereafter. Compact COCs were isolated from immature mice, primed 48 h earlier with 5 IU PMSGs, and were induced to expand in vitro with 100 ng/ml FSH in the presence of 1% FCS. Full expansion was achieved at 16 h, when hyaluronan synthesis ceased. Release of hyaluronan and CCs from the COC matrix began between 18 and 20 h of culture, which indicates that matrix degradation started at this time. PA activities in culture media were determined by SDS-PAGE, followed by a zymography at various time intervals between 4 and 32 h of culture. Secreted tissue type PA and uPA activity abruptly increased between 16 and 20 h after FSH stimulation. Slot blot hybridization of CC messenger RNA showed that uPA messenger RNA levels correlated with the increase in uPA activity. Similar temporal patterns of PA synthesis and matrix degradation were found in COCs induced to expand in vivo by injection of 5 IU human CG into PMSG-primed mice. Cultures of CCs, both in the presence and absence of oocytes, revealed that uPA synthesis is repressed in FSH-stimulated CCs by an oocyte-soluble factor for the first 16 h of culture, whereas CC responsiveness to this factor is lost thereafter. In conclusion, the data show that a sophisticated interplay between oocyte and CCs causes the two cell types to simultaneously secrete PA activity after ovulation. The fact that matrix degradation parallels PA production strongly supports the hypothesis that these enzymes may destabilize the expanded COC matrix.

Hyaluronic acid and proteoglycan accumulation in the cumulus oophorus matrix

A factor produced by the oocytes induces in vitro FSH-treated cumulus and mural granulosa cells to synthesize hyaluronic acid. In the present study we examined hyaluronic acid synthesis by the two cell populations in vivo. After injection of hCG into PMSG-primed immature mice, cumulus and mural granulosa cells adjacent to the antrum synthesized a large amount of such glycosaminoglycan, while the outermost layers layers of mural granulosa cells did not. The results suggest that in vivo differences in hyaluronic acid synthesis between follicle cell subpopulations depend on a diffusion gradient of the oocyte factor. We also identified a proteoglycan species synthesized by cumulus cells which may contribute to hyaluronic acid organization in the intercellular spaces.

Paracrine actions of oocytes in the mouse pre-ovulatory follicle

In mammals, ovulation requires a tight control of extracellular matrix modifications, within both the follicle wall and the inner mass of granulosa cells surrounding the oocyte, namely the cumulus cells. During the pre-ovulatory period, mural granulosa cells promote selective degradation of perifollicular matrix, resulting in the formation of a follicle rupture site. Conversely, cumulus cells synthesize a large amount of a muco-elastic matrix that plays an essential role in the extrusion of the oocyte from the follicle and in the subsequent fertilization process. Formation of such matrix by cumulus cells in the pre-ovulatory follicle appears to be controlled by a paracrine influence by the oocyte. We have shown that mouse oocytes modulate the response of cumulus cells to an ovulatory gonadotropin stimulus by promoting the synthesis and preventing the degradation of cumulus matrix. Therefore, although gonadotropins are essential for triggering the complex events involved in ovulation, the oocyte appears to have an active role in this process. In the present review current data and hypotheses concerning molecular mechanisms involved in the organization and synthesis of cumulus matrix are discussed.

New insights into regional systolic and diastolic left ventricular function with tissue Doppler echocardiography: from qualitative analysis to a quantitative approach

Tissue Doppler echocardiography is a variation of conventional Doppler flow imaging. This modality allows quantification of the Doppler shift within the range of myocardial tissue motion. The velocity at a variety of myocardial sites can be determined and distinguished very rapidly by using Doppler techniques. The velocity of moving tissue can be studied with pulsed wave tissue Doppler sampling, which displays the velocity of a selected myocardial region against time, with high temporal resolution. In addition, the velocities can be calculated with time-velocity maps and displayed as color-encoded velocity maps in either an M-mode or 2-dimensional format. This review will focus on the technical aspects and the different methods of tissue Doppler echocardiography for the analysis of regional systolic and diastolic left ventricular function. Whereas pulsed wave tissue Doppler echocardiography allows measurements of velocities of a selected myocardial region, color tissue Doppler gives the best overview of cardiac dynamics because the entire scanned color data are displayed simultaneously. However, there is an increasing need for objective evaluation of tissue Doppler information. Digital images and postprocessing of the data allow for quantitative off-line analysis, and the different approaches and parameters proposed from different centers are discussed.

From digital image processing of colour Doppler M-mode maps to noninvasive evaluation of the left ventricular diastolic function: a dedicated software package

Noninvasive estimation of diastolic pressure gradients has recently been validated using the space-temporal velocity distribution available from colour Doppler M-mode (CDM). However, the methods currently applied for analysing CDM patterns of left ventricular (LV) filling have limitations, such as lack of automation, subjective variability and limited use of digital velocity map. For this reason, we have developed software able to acquire and process the CDM maps; thus, providing an easily interpretable graphical and numerical display. The pressure field is obtained by approximating the derivatives with centred finite differences via the incompressible Navier-Stokes equations. After digital filtering of the noise and the removal of the colour black spots, the velocity field is utilised to compute the pressure gradient field and the pressure values by spatial integration. It is concluded that automatic quantification of colour CDM patterns is feasible and will be a strategic tool in the investigation of one of the most intriguing topics in cardiology.

[Tissue Doppler: the physical principles, representational and analytical modalities and clinical applications]

Tissue Doppler imaging or myocardial velocity imaging is a variation of conventional Doppler. This modality allows the quantification of the Doppler shift within the range of myocardial tissue motion. The velocity of motion at a variety of myocardial sites can be determined and distinguished very rapidly using Doppler techniques. The velocity of moving tissue can be studied with pulsed wave tissue Doppler sampling, which displays the velocity of a selected myocardial region against time, with high temporal resolution. In addition, the velocities can be calculated with time velocity maps and displayed as color coded velocity maps in either M-mode or two-dimensional format. This review will focus on the technical aspects and the different methods of tissue Doppler for regional systolic and diastolic left ventricular function analysis. While pulsed wave tissue Doppler allows us to measure the velocities of a selected myocardial region, color tissue Doppler gives the best overall view of cardiac dynamics because the whole scanned color data are displayed simultaneously. However, there is an increasing need for objective evaluation of tissue Doppler information. Digital images and data post-processing allow for quantitative off-line analysis, and the different approaches and parameters proposed from different centers are discussed. In recent years, tissue Doppler imaging has been applied for accurate evaluation of diastolic function, quantifying regional function particularly during stress, pre-excitation syndrome, and left ventricular hypertrophy. The results of these experiences indicate that tissue Doppler imaging is a promising technique for quantifying the response of the myocardium and endocardium during both normal and abnormal function. Again, there is a significant learning curve concerning its application, but with experience it will be a useful and reproducible technique.

Three-dimensional echocardiography: where we are, where we are going

Three-dimensional reconstruction of the heart has been an important research goal ever since the introduction of two-dimensional echocardiography. Several directions have been followed. Most approaches towards three-dimensional echocardiography are off-line and are based on the sequential rotational scanning and acquisition of multiple cross-sectional images together with their spatial position and orientation using internal coordinate reference systems. From the reconstructed volumetric data set electronic slicing can be performed which allows any-plane and paraplane echocardiography. The availability and versatility using the volumetric data set permits the retrieval of an infinite number of cardiac cross-sections which allow more accurate and reproducible measurements of valve areas, masses and cavity volumes by obviating geometric assumptions. The application of algorithms based on light reflection to the grey scale data provides tissue-depicting information allowing for dynamic volume-rendered display in projection, up till now unavailable in cardiology. This capability decreases variability both in the quality and interpretation of complex pathology among investigators. Emerging clinical experience indicates the strong potential of three-dimensional echocardiography in qualitative and quantitative diagnostic appraisal of various cardiac problems. While the technique is ready for clinical applications, its widespread use can be facilitated by a number of improvements. Advances in computer technology can be applied to three-dimensional echocardiography offering an exciting opportunity to employ virtual reality and simulation of interventional and surgical procedures, to predict results and plan appropriate therapy. In the future new physiologic parameters will provide additional information and will allow us to address new clinical questions.

Prediction of cardiac events after uncomplicated acute myocardial infarction by clinical variables and dobutamine stress test

OBJECTIVES

We sought to determine the relative prognostic power of several clinical and dobutamine stress test variables in patients after a first uncomplicated acute myocardial infarction (AMI).

BACKGROUND

The value of dobutamine echocardiography (DE) for determining prognosis after AMI is not yet defined. In particular, the influence of dobutamine stress test response on the outcome of these patients is unknown.

METHODS

A graded predischarge DE (from 5 to 40 microg/kg/min, plus atropine if needed) was performed in 245 patients (mean age 60 +/- 10 years) with a first uncomplicated AMI.

RESULTS

At follow-up (17 +/- 13 months), an adverse outcome occurred in 40 patients: cardiac death in 7, nonfatal myocardial infarction in 9 (hard events = 16) and unstable angina requiring hospital readmission in 24. Significant predictors of adverse outcome by univariate analysis were positive DE, ischemic wall motion score index (WMSI), angina during DE and diabetes for all events, and positive DE, ischemic WMSI and age for hard events. At multivariate analysis, the only independent predictors of adverse outcome were positive DE, diabetes and angina during DE for all events, and positive DE and age for hard events. The presence of both age >60 years and a history of diabetes identified patients at high risk of cardiac events (event rate 37%), compared with patients <60 years and no diabetes (event rate 11%). In patients with intermediate risk (only one clinical risk factor, event rate 18%), DE added prognostic information (event rate 10% in the negatives, 25% in the positives and 35% in the positives with angina).

CONCLUSIONS

After uncomplicated AMI, dobutamine stress test variables offer additional prognostic information to clinical data.

Hyaluronan and proteoglycans in ovarian follicles

Proteoglycans are macromolecules formed by a protein backbone to which one or more glycosaminoglycan side chains are co-valently attached. They can be secreted by the cells, retained at the cell surface, or stored in intracellular vacuoles. Hyaluronan is an extremely long glycosaminoglycan which, at variance with other glycosaminoglycans, is released into the extracellular matrix as a free polysaccharide not co-valently linked to a core protein. Both proteoglycans and hyaluronan influence many aspects of cell behaviour by multiple interactions with other molecules. They are involved in matrix formation, cell-cell and cell-matrix adhesion, cell proliferation and migration, and show co-receptor activity for growth factors. Both proteoglycan and hyaluranon synthesis change significantly during ovarian follicle development and atresia. This review describes the structure of these molecules and their possible function in ovarian physiology.

Effects of early treatment with captopril and metoprolol singly or together on six-month mortality and morbidity after acute myocardial infarction. Results of the RIMA (Rimodellamento Infarto Miocardico Acuto) study. The RIMA researchers

The RIMA (Rimodellamento Infarto Miocardico Acuto) study was designed to assess the relative effects of angiotensin-converting enzyme (ACE) inhibition by captopril, beta-blocker therapy by metoprolol, and their combination in patients with a first acute myocardial infarction on: 1. echocardiographically detected left ventricular remodeling; 2. prognosis. The second goal will be the argument of the present paper. Two-hundred fifty < or = 75 years consecutive patients (mean age: 58 yrs, males = 203) with acute myocardial infarction were randomly allocated to receive for > or = 3 months captopril (up to 75 mg/day, Group 1), metoprolol (up to 200 mg/day, Group 2) or captopril + metoprolol (Group 3) starting in the first 24 hours after the onset of symptoms. Intravenous beta-blockers in the acute phase of myocardial infarction and all other cardioactive drugs were allowed. The effect of the randomized therapy at six months from admission to the coronary care unit was considered in relation to: 1. recurrence of spontaneous cardiac events and of elective revascularization procedures; 2. adverse reactions (hypotension, atrioventricular block, cough, allergy, need of beta-blockers in Group 1, need for ACE inhibition in Group 2) requiring treatment modification based on physician's decision.

RESULTS

Definite follow-up data were available in 226 patients and 195/226 patients (86%) had a complete treatment period. In these patients (per protocol analysis), 37 spontaneous cardiac events occurred: cardiac death = 6, non-fatal reinfarction = 9, unstable angina requiring hospitalization = 16, congestive heart failure = 6. Moreover, seven patients received a coronary revascularization procedure. Events occurred in 11/67 patients from Group 1, 16/63 patients from Group 2, 10/65 patients from Group 3 (16% vs 25% vs 15%, p = 0.28). The multiple logistic regression analysis demonstrated an increased odds ratio (OR) for spontaneous cardiac events in patients from Group 2 (OR = 2.82, 95% Cl: 1.16-6.87: p < 0.05). Elective revascularization procedures were statistically less frequent in patients treated with metoprolol (Group 1 = 9%, Group 2 = 1.6%, Group 3 = 0%; Group 1 vs Groups 2 and 3; p = 0.03). The intention-to-treat analysis on the overall population (226 patients) confirmed the presence of a trend towards a higher risk in patients from Group 2 (OR = 2.1, 95% Cl: 0.96-4.59; p = 0.06). Adverse reactions were observed in 16 patients from Group 1, 6 patients from Group 2 and 15 patients from Group 3 (22% vs 10% vs 23%; Group 2 vs Groups 1 and 3; p = 0.08). At the multivariate regression analysis, a trend towards less adverse reactions in patients assigned to the beta-blocker therapy alone was confirmed (OR = 0.41, 95% Cl: 0.15-1.13; p = 0.07).

CONCLUSIONS

In a randomized early post-infarction treatment strategy, ACE inhibition with captopril alone or in combination with metoprolol demonstrated an increased protection against spontaneous cardiac events at six months in comparison with metoprolol alone. On the other hand, the beta-blocker treatment was associated with a lower number of elective revascularization procedures and appeared better tolerated than ACE inhibition.

Prognostic value of myocardial viability in medically treated patients with global left ventricular dysfunction early after an acute uncomplicated myocardial infarction: a dobutamine stress echocardiographic study

BACKGROUND

Residual viable myocardium identified by dobutamine stress after myocardial infarction may act as an unstable substrate for further events such as subsequent angina and reinfarction. However, in patients with severe global left ventricular dysfunction, viability might be protective rather than detrimental. The aim of this study was to assess the impact on survival of echocardiographically detected viability in medically treated patients with global left ventricular dysfunction evaluated after acute uncomplicated myocardial infarction.

METHODS AND RESULTS

The data bank of the large-scale, prospective, multicenter, observational Echo Dobutamine International Cooperative (EDIC) study was interrogated to select 314 medically treated patients (271 men; age, 58+/-9 years) who underwent low-dose (</=10 microg x kg-1 x min-1) dobutamine for the detection of myocardial viability and high-dose dobutamine for the detection of myocardial ischemia (</=40 microg x kg-1 x min-1 with atropine </=1 mg) performed 12+/-6 days after an acute uncomplicated myocardial infarction and showing a moderate to severe resting left ventricular dysfunction (wall motion score index [WMSI] >1.6). Patients were followed up for 9+/-7 months. Low-dose dobutamine stress echocardiography identified myocardial viability in 130 patients (52%). Dobutamine-atropine stress echocardiography was positive for ischemia in 148 patients (47%) and negative in 166 patients (53%). During the follow-up, there were 12 cardiac deaths (3.8% of the total population). With the use of Cox proportional hazards model, delta low-dose WMSI (the variation between rest WMSI and low-dose WMSI) was shown to exert a protective effect by reducing cardiac death by 0.8 for each decrease in WMSI at low-dose dobutamine (coefficient, -0.2; hazard ratio, 0.8; P<0.03); WMSI at peak stress was the best predictor of cardiac death in this set of patients (hazard ratio, 14.9; P<0.0018).

CONCLUSIONS

In medically treated patients with severe global left ventricular dysfunction early after acute uncomplicated myocardial infarction, the presence of myocardial viability identified as inotropic reserve after low-dose dobutamine is associated with a higher probability of survival. The higher the number of segments showing improvement of function, the better the impact is of myocardial viability on survival. The presence of inducible ischemia in this set of patients is the best predictor of cardiac death.

Left ventricular ejection fraction in patients with normal and distorted left ventricular shape by three-dimensional echocardiographic methods: a comparison with radionuclide angiography

BACKGROUND

Serial evaluation of left ventricular (LV) ejection fraction (EF) is important for the management and follow-up of cardiac patients. Our aim was to compare LVEF calculated from two three-dimensional echocardiographic (3DE) methods with multigated radionuclide angiography (RNA), in patients with normal and abnormally shaped ventricles.

METHODS AND RESULTS

Forty-one consecutive patients referred for RNA underwent precordial rotational 3DE acquisition of 90 cut-planes. From the volumetric data set, LVEF was calculated by (a) Simpson's rule (3DS) through manual endocardial tracing of LV short-axis series at 3 mm slice distance and (b) apical biplane modified Simpson's method ( MS) in 29 patients by manual endocardial tracing of the apical four-chamber view and its computer-derived orthogonal view. Patients included three groups: A, 17 patients with LV segmental wall motion abnormalities; B, 13 patients with LV global hypokinesis; and C, 11 patients with normal LV wall motion. For all the 41 patients, there was excellent correlation, close limits of agreement, and nonsignificant difference between 3DS and RNA for LVEF calculation (r = 0.99, [-6.7, +6.9] and p = 0.9), respectively. For the 29 patients, excellent correlation and nonsignificant differences between LVEF calculated by both 3DS and BMS and values obtained by RNA were found (r = 0.99 and 0.97, p = 0.7 and p = 0.5, respectively). In addition, no significant difference existed between values of LVEF obtained from RNA, 3DS, and BMS by the analysis of variance (p = 0.6). The limits of agreement tended to be closer between 3DS and RNA (-6.8, +7.2) than between BMS and RNA (-8.3, +9.7). The intraobserver and inter-observer variability of RNA, 3DS, and BMS for calculating LVEF(%) were (0.8, 1.5), (1.3, 1.8), and (1.6, 2.6), respectively. There were closer limits of agreement between 3DS and RNA for LVEF calculation in A, B, and C patient subgroups [(-3.5, +5), (-8.4, +5.6), and (-7.8, +8.6)] than that between BMS and RNA [(-8.1, +10.7), (-11.9, +9.3), and (-9.1, +11.3)], respectively.

CONCLUSIONS

No significant difference existed between RNA, 3DS, and BMS for LVEF calculation. 3DS has better correlation and closer limits of agreement than BMS with RNA for LVEF calculation, particularly in patients with segmental wall motion abnormalities and global hypokinesis. 3DS has a comparable observer variability with RNA. Therefore the use of 3DS for serial accurate LVEF calculation in cardiac patients is recommended.

Coding sequence, exon-intron structure and chromosomal localization of murine TNF-stimulated gene 6 that is specifically expressed by expanding cumulus cell-oocyte complexes

Tumor necrosis factor stimulated gene-6 (TSG-6) has been previously shown to be induced in vitro in several cell types by proinflammatory cytokines, and in vivo in pathological conditions such as rheumatoid arthritis. In this study, we report the complete coding sequence for the mouse TSG-6 protein, and the exon intron structure and the chromosomal localization of the gene. We have identified a 1605 nt cDNA sequence from mouse cumulus cell oocyte complexes (COCs) induced to expand in vivo. The sequence contains an open reading frame of 825 nt that codes for the 275 amino acid TSG-6 protein. The gene contains six exons separated by 1.1-5.8 kb introns and has been localized to the murine chromosome 2 by linkage analysis. Comparative reverse transcription-polymerase chain reaction studies have revealed that TSG-6 mRNA is specifically expressed after COC expansion induced in vivo, identifying the first non-pathological process in which TSG-6 may play an important role. Since TSG-6 binds to hyaluronan and interacts with inter-alpha-trypsin inhibitor (IalphaI), molecules that are essential for matrix formation by COCs, this protein may have a structural role in the matrix or may enhance the antiproteolytic effect of IalphaI to protect the matrix from degradation.

Cardiac imaging for risk stratification with dobutamine-atropine stress testing in patients with chest pain. Echocardiography, perfusion scintigraphy, or both?

BACKGROUND

Pharmacological stress echocardiography and myocardial perfusion scintigraphy are used frequently for risk stratification in patients with suspected myocardial ischemia. However, their relative prognostic strength has never been explored.

METHODS AND RESULTS

Two hundred twenty consecutive patients with chest pain (mean age, 60 +/- 12 years; 124 men, 115 with previous myocardial infarction) were studied with dobutamine-atropine stress echocardiography (ECHO) and simultaneous 99mTc sestamibi single photon emission computed tomography imaging (MIBI). Ischemia was defined as deterioration in left ventricular wall motion and reversible perfusion defects, respectively. ECHO was positive for ischemia in 76 and MIBI in 91 patients (agreement, 77%; kappa = .51). During follow-up of 31 +/- 15 months, 24 patients had hard cardiac events (nonfatal myocardial infarction or cardiac death). By univariate analysis, age, history of congestive heart failure, and any abnormality or ischemia on ECHO or MIBI were associated with cardiac events. Multivariate analysis revealed that age, abnormal ECHO (odds ratio [OR], 18.9; 95% CI, 2.5 to 146.0) or MIBI (OR, 12.8; 95% CI, 1.7 to 98.3), and ischemia on ECHO (OR, 4.0; 95% CI, 1.6 to 9.9) or MIBI (OR, 3.0; 95% CI, 1.2 to 7.4) had independent predictive values. When ECHO was used as a first option, the addition of MIBI to all nonischemic ECHO studies decreased the OR from 4.0 (95% CI, 1.6 to 9.9) to 3.8 (95% CI, 1.4 to 10.2). Addition of MIBI confined to nonischemic ECHO studies in which target heart rate was not attained (nondiagnostic studies) increased the OR to a maximal 5.7 (95% CI, 2.2 to 15.0). In contrast, the addition of ECHO to nondiagnostic MIBI studies was not useful.

CONCLUSIONS

Dobutamine-atropine ECHO and MIBI provide comparable prognostic information. The addition of MIBI to ECHO may be useful in patients with nondiagnostic ECHO studies.

Hemodynamic changes, plasma catecholamine responses, and echocardiographically detected contractile reserve during two different dobutamine-infusion protocols

We studied hemodynamic changes, catecholamine responses, and the occurrence of improved wall thickening by echocardiography during two different dobutamine-infusion protocols. Forty-three patients were studied by using a stepwise incremental dobutamine dose-infusion protocol (10-40 microg/kg/min, 3-min intervals); a subgroup of 11 patients also underwent a continuous dobutamine-infusion protocol (10 microg/kg/min for 12 min) in random order. No patient used beta-blockers. At 3-min intervals, blood pressure, heart rate, and plasma concentrations of dobutamine, epinephrine, and norepinephrine were measured. The echocardiographic improvement of wall thickening was analyzed only in paired protocols by visual assessment in left ventricular regions with normal wall motion at rest. The mean heart rate increased in the continuous and stepwise protocols from 73 to 99 and 74 to 132 beats/min. There was no significant change in blood pressure response between the two protocols. The mean plasma dobutamine concentrations during the continuous and stepwise protocols at 0, 3, 6, 9, and 12 min were 0/0; 31/38; 80/203; 106/448; and 120/692 ng/ml, respectively. In each patient, a response curve was constructed for the plasma dobutamine concentration versus heart rate. The heart rate increment and dobutamine concentration at which wall thickening was detected were similar with both protocols (14 +/- 5 vs. 12 +/- 7 beats/min) and (80 +/- 40 vs. 92 +/- 48 ng/ml; mean +/- SD). Wall thickening was noted in two of 11 patients between 0 and 3 min and 11 of 11 patients between 3 and 6 min in both protocols. Catecholamine responses during the continuous and stepwise protocols were epinephrine, 23 versus 28/28 versus 36, and norepinephrine 301 versus 323/347 versus 519. Only norepinephrine plasma concentrations increased significantly during the stepwise protocol. A 6-min dobutamine infusion was sufficient during both protocols to reach an adequate plasma dobutamine concentration, which induced a detectable increase of wall thickening in all patients. There is a significant differences between the two protocols with regard to the plasma catecholamine changes, so some of the hemodynamic effects during the stepwise dobutamine-infusion protocol may be mediated through release of endogenous catecholamines.

Should the diagnosis of coronary artery disease be based on the evaluation of myocardial function or perfusion?

The aim of this review was to define the place of stress (exercise, dobutamine, and vasodilator) echocardiography in the context of perfusion scintigraphic techniques for the detection of coronary artery disease. Echocardiography and nuclear imaging have their strong and weak points. Echocardiography has the benefit of widespread availability, relatively low cost, portability, absence of radiation, safety, and determination of ischaemic threshold. However, echocardiographic imaging cannot be performed during treadmill exercise, the echocardiographic windows are variable with sometimes poor echogenicity, and interpretation is subjective and requires an important learning curve. Diagnostic comparisons were focused on studies involving echocardiographic and nuclear imaging in the same patients. These direct comparisons show that exercise or dobutamine echocardiography and perfusion imaging have similar accuracies for the detection and localization of coronary artery disease. Perfusion imaging may be more sensitive in the detection of mild coronary artery disease; echocardiography, however, has a better specificity. Vasodilator perfusion imaging is superior to vasodilator echocardiography, although the new dipyridamole-atropine echocardiography test will make future reassessment necessary. Once the condition of adequate echocardiographic training is fulfilled, we believe that the selection of one or other test should be tailored to clinical circumstances rather than be a uniform decision.

[Prognostic stratification after acute uncomplicated myocardial infarction: exercise test, echo-dobutamine test or both?]

OBJECTIVES

The aims of this study were: 1) to assess the relative prognostic value of predischarge dobutamine echocardiography (DE) and exercise electrocardiography (EE) in patients after a first uncomplicated acute myocardial infarction (AMI), and 2) to evaluate the optimal prognostic strategy by using the two tests in different combinations.

METHODS

DE (dobutamine infusion 5 to 40 micrograms/kg/min plus atropine 0.25 to 1 mg, if needed) and symptom-limited bicycle EE were performed in 208 patients (mean age 58 +/- 9 years, 90% males), on different days and in random order, 12 +/- 4 days after a first uncomplicated AMI and after pharmacological washout. A stress-induced dyssynergy and ST segment depression > 1 mm were considered criteria of positivity for DE and EE, respectively. Only spontaneous cardiac events were considered: cardiac death, reinfarction (= hard events), and unstable angina requiring hospitalization (= soft events).

RESULTS

Thirty-eight events occurred during follow-up (16 +/- 13 months; range: 1-44 months); 5 cardiac deaths, 6 reinfarctions and 27 unstable angina. Patients with a positive DE had a twofold increase in all event rates (26 vs 12%, p < 0.01) and a fourfold increase in the rate of hard events (9 vs 2%, p < 0.05). In contrast, no statistically significant difference was observed in the distribution of the same events between patients with positive and negative EE. Both tests showed similar negative (DE 88%, EE 85%) and positive (DE 26%, EE 24%) predictive values. Among six different strategies (performing either DE or EE only in all patients; EE in all patients; EE in all patients and DE only in those with a positive EE; and DE only in those with a negative EE; EE in all patients and DE only in those with anterior AMI), EE only in patients with inferior or non-Q AMI and DE only in those with anterior AMI), performing DE only in patients with a positive EE gave the highest predictive accuracy-74% (95% confidence intervals 68 to 80) for all events and 77% (95% confidence intervals 71 to 83) for hard events.

CONCLUSIONS

In patients with a first uncomplicated AMI, DE is useful in identifying patients at high and low risk of future spontaneous cardiac events. The optimal strategy for prognostication of these patients is to perform EE in all and DE only in the ones with a positive EE.

Accurate assessment of mitral valve area in patients with mitral stenosis by three-dimensional echocardiography

The accuracy of measurements of mitral valve orifice area (MVA) from three-dimensional echocardiographic (3DE) image data sets obtained by a transthoracic or transesophageal rotational imaging probe was studied in 15 patients with native mitral stenosis. The smallest MVA was identified from a set of eight parallel short-axis cut planes of the mitral valve between the anulus and the tips of leaflets (paraplane echocardiography) and measured by planimetry. In addition, MVA was measured from the two-dimensional short-axis view (2DE). Values of MVA measured by 3DE and 2DE were compared with those calculated from Doppler pressure half-time (PHT) as a gold standard. Observer variabilities were studied for 3DE. MVA measured from PHT ranged between 0.55 and 3.19 cm2 (mean +/- SD 1.57 +/- 0.73 cm2), from 3DE between 0.83 and 3.23 cm2 (mean +/- SD 1.55 +/- 0.67 cm2), and from 2DE between 1.27 and 4.08 cm2 (mean +/- SD 1.9 +/- 0.7 cm2). The variability of intraobserver and interobserver measurements for 3DE measurements was not significantly different (p = 0.79 and p = 0.68, respectively); for interobserver variability, standard error of the estimate = 0.25. There was excellent correlation, close limits of agreement (mean difference +/- 2 SD), and nonsignificant differences between 3DE and PHT for MVA measurements (r = 0.98 [0.02 +/- 0.3] and p = 0.6), respectively. There was moderate correlation, wider limits of agreement, and significant difference between 2DE and PHT for MVA measurements (r = 0.89 [0.32 +/- 0.66] and p = 0.002), respectively. This may be related to the difficulties in visualization of the smallest orifice in precordial short-axis views. This study suggests that three-dimensional image data sets, by providing the possibility of "computer slicing" to generate equidistant parallel cross sections of the mitral valve independently from physically dictated ultrasonic windows, allow accurate and reproducible measurement of the MVA.

Hyaluronan synthesis by mouse cumulus cells is regulated by interactions between follicle-stimulating hormone (or epidermal growth factor) and a soluble oocyte factor (or transforming growth factor beta1)

Expansion of the cumulus cell-oocyte complex (COC) in the preovulatory mammalian follicle requires a transient induction of hyaluronan (HA) synthesis by the cumulus cells. We studied the interactions of known factors that regulate this process by isolating compact COCs from mice and inducing their expansion in vitro. Maximum HA synthesis requires either follicle-stimulating hormone (FSH) or epidermal growth factor (EGF) in combination with either a soluble factor(s) produced by the oocyte or transforming growth factor beta1. FSH (or EGF) exerts its effects during the first 2 h of incubation, before HA synthesis actually begins. The oocyte factor(s) (or transforming growth factor beta1) exerts its effects from 2 h onwards and must be continuously present throughout the subsequent approximately 10 h to achieve a maximum level of HA synthesis. FSH stimulates intracellular cAMP synthesis, which correlates with net HA production up to approximately 14 fmol/COC at 5 ng/ml FSH; however, higher concentrations of FSH increase cAMP levels approximately 10-fold higher with no additional effect on HA synthesis. EGF at saturating concentrations for HA synthesis does not stimulate cAMP above basal levels. Tyrosine kinase inhibitors genistein and tyrphostin AG18 nearly abolish the HA synthesis response to EGF and inhibit the response to FSH by approximately 60%, suggesting that a tyrosine kinase activity is involved for both factors, whereas FSH also operates partially through another signaling pathway. Actinomycin D abolishes HA synthesis if added at the beginning of culture and reduces HA synthesis by approximately 50% if added between 6-12 h when HA synthesis is normally maximal. The results suggest that regulation of HA synthesis is primarily controlled at the transcriptional level.

Prognostic value of dobutamine echocardiography early after uncomplicated acute myocardial infarction: a comparison with exercise electrocardiography

OBJECTIVES

This study sought to assess the relative prognostic power of dobutamine echocardiography and exercise electrocardiography after acute myocardial infarction.

BACKGROUND

The prognostic value of dobutamine echocardiography early after acute myocardial infarction has not yet been reported.

METHODS

One hundred seventy-eight patients (mean age 58 +/- 9 years) with a first uncomplicated acute myocardial infarction underwent predischarge dobutamine echocardiography (5 to 40 micrograms/kg body weight per min, plus atropine if needed) and symptom-limited bicycle exercise electrocardiography and were followed up for 17 +/- 13 months. Stress-induced dyssynergy and ST segment depression > 1 mm were considered criteria of positivity for dobutamine echocardiography and exercise electrocardiography, respectively.

RESULTS

Dobutamine echocardiography was positive in 83 patients and exercise electrocardiography in 60. At follow-up there were 5 deaths, 6 nonfatal myocardial infarctions (11 hard events) and 20 cases of unstable angina. Dobutamine echocardiography and exercise electrocardiography had similar negative predictive values both for all events (88% and 86%, respectively) and for hard events (98% and 95%, respectively). The hard events rate was significantly higher in patients with positive rather than negative dobutamine echocardiography (relative risk [RR] 5.15, 95% confidence interval [CI] 1.14 to 23.16), although there was no difference between patients with positive and negative exercise electrocardiograms. When Cox analysis was performed, dobutamine echocardiography had an independent prognostic value both for all events (RR 2.88, 95% CI 1.37 to 6.08) and for hard events (RR 6.56, 95% CI 1.42 to 30.46).

CONCLUSIONS

After uncomplicated acute myocardial infarction, dobutamine echocardiography and exercise electrocardiography have a similar high negative predictive value for both all events and hard events only. Positive dobutamine echocardiography, but not positive exercise electrocardiography, identifies a group of patients at higher risk of subsequent cardiac events.

Coding sequence of a hyaluronan synthase homologue expressed during expansion of the mouse cumulus-oocyte complex

Maturation of mammalian cumulus cell-oocyte complex in the preovulatory follicle involves the deposition of a hyaluronan-rich extracellular matrix by the cumulus cells. In this study, we report the complete coding sequence of a novel mouse hyaluronan synthase homologue expressed in cumulus cell-oocyte complexes induced to expand in vivo. The time frame of mRNA expression of this molecule correlates well with previous biochemical and immunohistochemical findings on the initiation of hyaluronan synthesis in maturing preovulatory follicles. Evolutionary comparison of the vertebrate hyaluronan synthase homologues indicates that there are at least two genes that code for these proteins.

Cardiac arrest during dobutamine stress echocardiography

In this report, we describe the case of a woman with normal coronary arteries who experienced a cardiac arrest during a dobutamine stress test. The patient was successfully treated with external cardiac massage. The possible mechanisms underlying this unusual life-threatening side effect of dobutamine infusion are discussed.

[Three-dimensional transesophageal echocardiography: a new cardiologic diagnostic tool. Initial experience with 150 patients]

BACKGROUND

Three-dimensional transesophageal echocardiography is a new diagnostic tool and its potential has been investigated mainly in international centers dealing with research in the field of cardiac pathologies. The clinical usefulness and the potential additional information over multiplane transesophageal echocardiography in daily clinical practice have not been exstensively studied.

OBJECTIVES

This study sought to assess the feasibility and to define the potential role of three-dimensional technique in a clinical cardiology department.

POPULATION AND METHODS

One hundred-fifty patients (73 males, 77 females) aged 17-82 underwent a three-dimensional transesophageal echocardiographic study. Indications for the study were the following: 39 mitral (26%), 13 aortic (8%) and 4 tricuspidal (2%) valvulopathies, 23 valvular prostheses (15%), 6 aortic diseases (4%), 16 sources of embolism (10%), 16 congenital heart diseases (10%), 14 ischemic heart diseases (9.3%), 14 cardiomyopathies (9%), 5 other pathologies (3%). The 3 D examination quality was graded as insufficient, sufficient and good. The information obtained by "volume rendered" and "anyplane" three-dimensional echocardiography were compared with the traditional two-dimensional images to determine whether they provided additional information.

RESULTS

A total of 288 acquisitions were obtained in the 150 patients (1.9 acquisitions per patient). Examinations were graded of good quality in 99 patients (61%), sufficient in 36 (24%) and insufficient in 15 patients (10%). Additional informations were obtained in 33 patients (22%) by "volume rendered" echocardiography and by "anyplane echocardiography", including mitral regurgitation or repair for valvular prolapse (11 patients), aortic valve malformations and endocarditis (4 patients), congenital heart diseases (9 patients), right ventricular dysplasia (6 patients) or hypertrophic cardiomyopathy (1 patient), tricuspid regurgitation (2 patients). The additional information were obtained in patients in the group of good 3 D reconstructions quality in all but two cases.

CONCLUSIONS

The diagnostic use of the transesophageal technique with 3 D facilities permitted to obtain an overall 22% of additional information. These results will stimulate further study to evaluate the advantages of the three-dimensional technique in specific clinical fields of application.

Endocrine and paracrine regulation of cumulus expansion

In a Graafian follicle, granulosa cells are classified into two principal cell subpopulations: cumulus cells, which are closely associated with the oocyte to form the cumulus cell-oocyte complex (COC), and mural granulosa cells, which are organised as a stratified epithelium at the periphery of the follicle. Following the preovulatory gonadotropin surge, cumulus cells lose contact with mural granulosa cells and start to synthesise and secrete a large amount of hyaluronan (HA), a glycosaminoglycan with high molecular weight and large hydrodynamic domains (Salustriet al., 1992). Proteins derived from serum (Chenet al., 1992, 1994) and synthesised by cumulus cells (Camaioniet al., 1993, 1996) organise the strands of HA into an intercellular elastic network that traps the cumulus cells and the oocyte in a unit which can not be mechanically dissociated – a process also referred to as cumulus expansion. At ovulation, the expanded COC is released through the ruptured follicle wall and transferred to the oviduct. The matrix in the expanded COC facilitates its extrusion from the follicle and its capture by oviductal fimbria, and provides, together with the cumulus cells, a suitable microenvironment for sperm penetration and fertilisation (for references see Salustriet al., 1993).

Three-dimensional echocardiography of the thoracic aorta

OBJECTIVES

The feasibility and diagnostic potential of three-dimensional echocardiography, using transoesophageal multiplane echocardiography for the assessment of thoracic aortic pathology, has not been evaluated.

METHODS

We studied 21 patients (10 women, 11 men), mean age 52.1 years (range 20-78). Images for three-dimensional reconstruction were acquired during a diagnostic multiplane transoesophageal echocardiographic examination. In all, 30 acquisitions were performed: 19 of the ascending aorta and 11 of the arch and descending aorta. Three-dimensional reconstruction was performed to visualize normal aortic segments in three patients with a normal thoracic aorta, postoperative anatomy in seven, chronic aortic dissection in two, non-dissecting aneurysm in seven (three patients had coexisting thrombi) and protruding aortic atheroma in two.

RESULTS

Three-dimensional image quality was scored excellent in 17 acquisitions (57%), adequate in 10 (33%) and inadequate in three (10%). Anyplane two-dimensional views of regions of interest of the aorta were reconstructed off-line from the data sets, which provided improved analysis with potential for quantitation. Advanced computer-assisted imaging modalities (electronic vivisection, lumen cast display, detail extraction) were feasible.

CONCLUSIONS

We conclude that three-dimensional echocardiography of the thoracic aorta is feasible. Adequate image quality is obtained in the vast majority of patients, which adds additional qualitative and quantitative information to routine multiplane transoesophageal echocardiographic studies.

Assessment of left ventricular outflow in hypertrophic cardiomyopathy using anyplane and paraplane analysis of three-dimensional echocardiography

This study analyzes the alterations in size and geometry of the left ventricular (LV) outflow tract that occur in hypertrophic cardiomyopathy (HC) using transthoracic 3-dimensional echocardiography. Transthoracic 3-dimensional echocardiography was performed in 17 patients with HC (4 after myectomy) and in 10 normal subjects. Images were acquired with the rotational approach, with electrocardiographic and respiratory gating. From the 3-dimensional datasets, short-axis parallel slicing of the LV outflow tract at a 1mm distance was performed at the onset of systole. For each slice, cross-sectional area and maximal and minimal diameter were calculated. Reconstruction of the LV outflow tract could be displayed in 3 dimensions in all patients, allowing orientation and clear definition of the irregular geometry. In patients with HC, the minimal LV outflow tract cross-sectional area was smaller than in normal subjects (2.3 +/- 1.0 vs 5.0 +/- 0.9 cm(2), p < 0.0001). The ratio between maximal and minimal cross-sectional areas was higher in patients with HC than in normal subjects (2.6 +/- 0.9 vs 1.4 +/- 0.2, p <0.0001). The ratio between maximal and minimal diameter of the smallest cross section of the LV outflow tract was also significantly higher in patients with HC than in normal subjects (1.6 +/- 0.3 vs, 1.2 +/- 0. 1, p <0.001); a value of 1.36 separated normal subjects from HC patients without previous myectomy. In conclusion, precordial 3-dimensional echocardiography allows detailed qualitative and quantitative information on the LV outflow tract. Patients with HC are characterized by a highly eccentric and asymmetric shape of the LV outflow tract, and by a smaller minimal cross-sectional area than that seen in normal subjects.

Accurate measurement of left ventricular ejection fraction by three-dimensional echocardiography. A comparison with radionuclide angiography

BACKGROUND

Three-dimensional echocardiography is a promising technique for calculation of left ventricular ejection fraction, because it allows its measurement without geometric assumptions. However, few data exist that study its reproducibility and accuracy in patients.

METHODS AND RESULTS

Twenty-five patients underwent radionuclide angiography and three-dimensional echocardiography that used the rotational technique (2 degrees interval and ECG and respiratory gating). Left ventricular volume and ejection fraction were calculated by use of Simpson's rule at a slice thickness of 3 mm. Analyses were performed to define the largest slice thickness required for accurate calculation of left ventricular volume and ejection fraction. Three-dimensional echocardiography showed excellent correlation with radionuclide angiography for calculation of left ventricular ejection fraction (mean +/- SD, 38.9 +/- 19.8 and 38.5 +/- 18.0, respectively; r = .99); their mean difference was not significant (0.03 +/- 0.17; P = .3), and they had a close limit of agreement (-0.385, 0.315). Intraobserver variability for radionuclide angiography and three-dimensional echocardiography was 4.2% and 2.6%, respectively, whereas interobserver variability was 6.2% and 5.3%, respectively. There was no significant difference between left ventricular volume and ejection fraction calculated at a slice thickness of 3 mm and that calculated at different slice thicknesses up to 24 mm. However, the standard deviation of the mean difference showed a stepwise increase, particularly at thicknesses > 15 mm. At a slice thickness of 15 mm, the probability of three-dimensional echocardiography to detect > or = 6% difference in ejection fraction was 80%.

CONCLUSIONS

Three-dimensional echocardiography has excellent correlation with radionuclide angiography for calculation of left ventricular ejection fraction in patients and has an observer variability similar to that of radionuclide angiography. We recommend the use of a 15-mm-thick slice for accurate and rapid measurement of left ventricular volume and ejection fraction.

Low-dose dobutamine echocardiography and rest-redistribution thallium-201 tomography in the assessment of spontaneous recovery of left ventricular function after recent myocardial infarction

Spontaneous improvement of contraction and perfusion occurs after acute myocardial infarction. The relative merit of low-dose dobutamine stress echocardiography (LDDE) and rest-redistribution thallium scintigraphy (RR TI) in this setting has not been evaluated. We studied 30 patients at 7 +/- 3 days after acute myocardial infarction with LDDE (5 to 10 micrograms/kg/min) and RR TI single photon emission computed tomography. Viability was defined as improvement of wall thickening at LDDE in the presence of redistribution or a defect with uptake > or = 50% of peak activity at RR TI. Baseline echocardiography and RR TI were repeated after 3 months. In 112 dyssynergic segments, viability was detected in 60 (54%) by RR TI and in 39 (35%) by LDDE (p < 0.005). Spontaneous improvement of function was detected in 35 (31 %) segments. In the same regions, thallium uptake increased significantly. The sensitivity, specificity, and accuracy of LDDE for predicting late improvement of wall motion were 77%, 84%, and 82%, respectively. Those of RR TI were 77%, 57%, and 63%, respectively. Specificity and accuracy of LDDE were higher than RR TI (p < 0.005). We conclude that a myocardial viability pattern after acute myocardial infarction is more frequently detected by RR TI than by LDDE. Both techniques are equally sensitive, but LDDE is a more specific predictor of spontaneous recovery of regional left ventricular function.

Three-dimensional echocardiography of normal and pathologic mitral valve: a comparison with two-dimensional transesophageal echocardiography

OBJECTIVES

This study was done to ascertain whether three-dimensional echocardiography can facilitate the diagnosis of mitral valve abnormalities.

BACKGROUND

The value of the additional information provided by three-dimensional echocardiography compared with two-dimensional multiplane transesophageal echocardiography for evaluation of the mitral valve apparatus has not been assessed.

METHODS

Thirty patients with a variety of mitral valve pathologies (stenosis in 8, insufficiency in 12, prostheses in 10) and 20 subjects with a normal mitral valve were studied. Images were acquired using the rotational technique (ever 2 degrees), with electrocardiographic and respiratory gating. From the three-dimensional data sets, cut planes were selected and presented in both two-dimensional format (anyplane echocardiography) and volume-rendered dynamic display. The data were compared with the original multiplane two-dimensional images. Different features of the mitral valve apparatus were defined and graded by three observers for clarity of visualization and confidence of interpretation as 1) inadequate, 2) sufficient, or 3) excellent.

RESULTS

All the techniques provided good visualization of the mitral valve (mean global scores +/- SD for multiplane, anyplane and volume-rendered echocardiography were 2.22 +/- 0.34, 2.24 +/- 0.26 and 2.30 +/- 0.25, respectively). With volume-rendered echocardiography, the mitral valve apparatus was scored higher in pathologic than in normal conditions (2.38 +/- 0.24 vs. 2.16 +/- 0.21, p < 0.002). The spatial relationships between the mitral valve and other structures, leaflet mobility, commissures and orifice were scored higher by volume-rendered echocardiography. Prostheses were evaluated equally well by the three methods. Multiplane and anyplane echocardiography were superior for the evaluation of leaflet thickness, subvalvular apparatus and annulus.

CONCLUSIONS

Transesophageal three-dimensional echocardiography facilitates imaging of some features of the mitral valve apparatus and provides additional information for comprehensive assessment of mitral valve abnormalities.

T wave normalization during dobutamine stress testing in patients with non-Q wave myocardial infarction. A marker of myocardial ischaemia?

Conflicting results in a heterogenous patient population have been described on the functional significance of stress-induced T wave normalization in the ECG. The aim of this study was to evaluate the relationship between T wave normalization during dobutamine stress testing and stress-induced ischaemia evaluated by echocardiography and myocardial perfusion scintigraphy in patients with previous non-Q wave myocardial infarction. Among 520 patients who underwent dobutamine stress, testing in conjunction with simultaneous echocardiography and 201 thallium or sestamibi SPECT for evaluation of suspected myocardial ischaemia, 36 were selected according to the following criteria: previous non-Q wave myocardial infarction, normal QRS, negative T waves in two or more ECG leads and no significant ST segment depression or elevation at rest or during stress. Diagnosis of ischaemia relied upon the occurrence of reversible perfusion defects by scintigraphy and stress-induced wall motion abnormalities by echocardiography. During the test, T wave normalization (defined as a resting negative T wave becoming upright in one or more ECG leads during stress) occurred in 20 patients (group 1), while in 16 patients the T waves remained negative (group 2). The prevalence of ischaemia was higher in group 1 than in group 2 both by scintigraphy (85% vs 38%, P = 0.004) and by echocardiography (70% vs 32%, P = 0.02). The sensitivity, specificity and accuracy of T wave normalization in the detection of ischaemia were 74%, 77% and 75% by SPECT and 74%, 65% and 69% by echocardiography respectively.

CONCLUSION

In patients with non-Q wave myocardial infarction and suspected myocardial ischaemia, T wave normalization without concomitant ECG changes during dobutamine stress testing is associated with a higher prevalence of ischaemia compared to patients with persistent T wave inversion. This ECG finding should not be disregarded as a marker of ischaemia in that particular patient population.

Proteoglycans and proteins in the extracellular matrix of mouse cumulus cell-oocyte complexes

In the preovulatory follicle, the oocyte is surrounded by approximately 1000 closely associated cumulus cells forming the compact form of the cumulus cell-oocyte complex (COC). In response to the gonadotropin surge, the COC in a follicle destined for ovulation undergoes expansion when the cumulus cells synthesize and organize an extensive extracellular matrix enriched in hyaluronan. Successful expansion of the COC appears to be essential for ovulation and ultimately for fertilization. We studied this process in vitro by isolating compact COCs from preovulatory mouse follicles and incubating them under conditions which promote COC expansion by retention of newly synthesized hyaluronan (HA in the extracellular matrix around the cells. [3H]-Leucine and [35S]sulfate were used as precursors to label macromolecules synthesized by the cells that may be necessary for organizing the HA in this matrix. After labeling, expanded COCs were washed to remove medium and any labeled molecules that were not associated with the matrix. Macromolecules selectively associated with the matrix were then solubilized by digesting the expanded COCs briefly with Streptomyces hyaluronidase, an enzyme that specifically cleaves HA. Cells were removed by centrifugation, and the digest supernate was analyzed by molecular sieve chromatography and SDS-PAGE. A dermatan sulfate proteoglycan of large hydrodynamic size ( > 1 million Da) and a approximately 46-kDa protein were the predominant labeled species identified. The proteoglycan has properties similar to proteoglycans such as aggrecan and versican which interact specifically with HA. The approximately 46-kDa protein has the same molecular size as the link protein which interacts with HA and HA-binding proteoglycans to form stable ternary complexes in a variety of extracellular matrices. We propose that the dermatan sulfate proteoglycan and the approximately 46-kDa protein synthesized by the cumulus cells form similar ternary complexes that are necessary for retaining HA in the COC matrix and hence are required for successful COC expansion.

Three-dimensional echocardiography of a flail tricuspid valve

A 71-year-old man with an old myocardial infarction and blunt chest trauma 2 years previously came to our hospital with increasing dyspnea. Three-dimensional echocardiography was performed and a ruptured papillary muscle with flail anterior tricuspid valve was demonstrated from a surgical perspective (electronic atriotomy). These findings were confirmed during open-heart surgery with close similarity.