Cardiogenic shock due to tachycardiomyopathy after heart transplantation: successful treatment with ivabradine.

Tachycardia-induced cardiomyopathy refers to an impairment in left-ventricular function due to chronic or prolonged tachycardia. We describe a heart transplant patient who developed cardiogenic shock due to tachycardia-induced cardiomyopathy. Low-output failure was further aggravated by administration of a short-acting beta-blocker during invasive hemodynamic monitoring. In contrast, heart rate control by administration of increasing doses of ivabradine supported recovery from cardiogenic shock and led to an improvement in the patient's clinical condition as well as left-ventricular function during follow-up.

[Perioperative therapy with antiplatelet agents]. / Perioperative Therapie mit Thrombozytenaggregationshemmern.

Antiplatelet therapy is used to prevent thromboembolic complications in patients with artherothrombotic disease. In clinical routine an assessment of the risk of perioperative bleeding must be weighed against the risk of thromboembolic complications in the event of discontinuation of antiplatelet agents. The indications as well as the timepoint for the termination of antiplatelet therapy are important issues to consider. The premature interruption of oral antiplatelet therapy with recovery of platelet function may lead to recurrence of thromboembolic events. Especially patients with intracoronary stents are at threat when the dual platelet therapy is interrupted before complete endothelialization of the stent.

Relation of coronary flow pattern to myocardial blush grade in patients with first acute myocardial infarction.

BACKGROUND: Analysis of myocardial blush grade (MBG) and coronary flow velocity pattern has been used to obtain direct or indirect information about microvascular damage and reperfusion injury after percutaneous transluminal coronary angiography for acute myocardial infarction. OBJECTIVE: To evaluate the relation between coronary blood flow velocity pattern and MBG immediately after angioplasty plus stenting for acute myocardial infarction. DESIGN: The coronary blood flow velocity pattern in the infarct related artery was determined immediately after angioplasty in 35 patients with their first acute myocardial infarct using a Doppler guide wire. Measurements were related to MBG as a direct index of microvascular function in the infarct zone. RESULTS: Coronary flow velocity patterns were different between patients with absent myocardial blush (n = 14), reduced blush (n = 7), or normal blush (n = 14). The following variables (mean (SD)) differed significantly between the three groups: systolic peak flow velocity (cm/s): absent blush 10.9 (4.2), reduced blush 14.2 (6.4), normal blush 19.2 (11.2); p = 0.036; diastolic deceleration rate (ms): absent blush 103 (58), reduced blush 80 (65), normal blush 50 (19); p = 0.025; and diastolic-systolic velocity ratio: absent blush 4.06 (2.18), reduced blush 2.02 (0.55), normal blush 1.88 (1.03); p = 0.002. In a multivariate analysis MBG was the only variable with a significant impact on the diastolic deceleration rate (p = 0.034,) while age, infarct location, time to revascularisation, infarct vessel diameter, and maximum creatine kinase had no significant impact. CONCLUSIONS: The coronary flow velocity pattern in the infarct related epicardial artery is primarily determined by the microvascular function of the dependent myocardium, as reflected by MBG.

Comparison of oesophageal and gastric air tonometry in patients with circulatory failure.

BACKGROUND: Gastric PCO2 measured by balloon tonometry can estimate the adequacy of splanchnic perfusion. However, enteral feeding and gastric content can interfere with gastric PCO2 assessment. Tonometry in other sites of the body could avoid these problems. We therefore tested the hypothesis that oesophageal air tonometry would give results similar to gastric tonometry. METHODS: We studied 20 consecutive patients (mean age 68 (SD 9) [range 49-81] yr, 18 males, SAPS II score 55 (SD 18), ICU mortality 55%) with circulatory disorders during mechanical ventilation in the intensive care unit. Tonometer probes were placed via the nose, one into the stomach and the other in the oesophagus. PCO2 was measured with two automated gas analysers, at admission and 30 min, 1, 2, 3, 32, 40, and 48 h thereafter. RESULTS: One hundred and forty-eight paired measurements were obtained. Gastric PCO2 was greater than oesophageal PCO2 on admission (7.19 (1.43) vs 5.89 (0.73) kPa, P < 0.01) and subsequently. Differences between the measures correlated (r = 0.67) with the mean absolute value, indicating that overestimation increased as gastric PCO2 increased. CONCLUSIONS: Oesophageal PCO2 is less than gastric PCO2, and the difference is greater when gastric PCO2 levels are greater. Air tonometry may not measure regional PCO2 levels in the oesophagus satisfactorily. Other methods and sites for carbon dioxide tonometry should be examined.

Predictive value of markers of myocardial reperfusion in acute myocardial infarction for follow-up left ventricular function.

This study evaluated recently suggested invasive and noninvasive parameters of myocardial reperfusion after acute myocardial infarction (AMI), assessing their predictive value for left ventricular function 4 weeks after AMI and reperfusion defined by myocardial contrast echocardiography (MCE). In 38 patients, angiographic myocardial blush grade, corrected Thrombolysis In Myocardial Infarction frame count, ST-segment elevation index, and coronary flow reserve (n = 25) were determined immediately after primary percutaneous transluminal coronary angioplasty (PTCA) for first AMI, and intravenous MCE was determined before, and at 1 and 24 hours after PTCA to evaluate myocardial reperfusion. Results were related to global wall motion index (GWMI) at 4 weeks. MCE 1 hour after PTCA showed good correlation with GWMI at 4 weeks (r = 0.684, p <0.001) and was in an analysis of variance the best parameter to predict GWMI 4 weeks after AMI. The ST-segment elevation index was close in its predictive value. Considering only invasive parameters of reperfusion myocardial blush grade was the best predictor of GWMI at 4 weeks (R(2) = 0.3107, p <0.001). A MCE perfusion defect size at 24 hours of > or =50% of the MCE perfusion defect size before PTCA was used to define myocardial nonreperfusion. In a multivariate analysis, low myocardial blush grade class was the best predictor of nonreperfusion defined by MCE. Thus, intravenous MCE allows better prediction of left ventricular function 4 weeks after AMI than other evaluated parameters of myocardial reperfusion. Myocardial blush grade is the best predictor of nonreperfusion defined by MCE and is the invasive parameter with the greatest predictive value for left ventricular function after AMI. Coronary flow parameters are less predictive.

Serial evaluation of perfusion defects in patients with a first acute myocardial infarction referred for primary PTCA using intravenous myocardial contrast echocardiography.

AIMS: To investigate whether myocardial contrast echocardiography using Sonazoid could be used for the serial evaluation of the presence and extent of myocardial perfusion defects in patients with a first acute myocardial infarction treated with primary PTCA, and specifically, (1) to evaluate safety and efficacy of myocardial contrast echocardiography to detect TIMI flow grade 0--2, (2) to evaluate the success of reperfusion and (3) to predict left ventricular recovery after 4 weeks follow-up. METHODS AND RESULTS: Fifty-nine patients underwent serial myocardial contrast echocardiography, immediately before primary PTCA (MCE1), 1 h (MCE2) and 12--24 h after PTCA (MCE3). A perfusion defect was observed in 21 of 24 patients (88%) with anterior acute myocardial infarction. All but one had TIMI flow grade 0--2 prior to PTCA. Nine of 31 patients (29%) with inferior acute myocardial infarction showed a perfusion defect and all had TIMI flow grade 0-2 prior to PTCA. Restoration of TIMI flow grade 3 was achieved in 73% of the patients by primary PTCA. A reduction in size of the initial perfusion defect of at least one segment (16 segment model) or no defect vs persistent defect in patients with anterior acute myocardial infarction was associated with improved global left ventricular function at 4 weeks; mean global wall motion score index 1.29+/-0.21 vs 1.66+/-0.31 (P=0.009). Multiple regression analysis in patients with an anterior acute myocardial infarction revealed that the extent of the perfusion defect at MCE3 was a significant (P=0.0005) independent predictor for left ventricular recovery at 4 weeks follow-up. The only other independent predictor was TIMI flow grade 3 post PTCA (P=0.007). CONCLUSION: Intravenous myocardial contrast echocardiography immediately prior to primary PTCA seems safe and is capable of detecting the presence of a perfusion defect and its subsequent dynamic changes, particularly in patients with a first anterior acute myocardial infarction. A significant reduction in size of the initial perfusion defect using serial myocardial contrast echocardiography predicts functional recovery after 4 weeks and these findings underscore the potential diagnostic value of intravenous myocardial contrast echocardiography.

Shu 508 A (Levovist)-enhanced Doppler echocardiography improves the assessment of valvular heart disease.

OBJECTIVE: To investigate whether intravenous injection of SHU 508 A improves the diagnostic accuracy of Doppler echocardiography in the assessment of valvular pathologies. METHODS AND RESULTS: One hundred and twenty-five consecutive patients with valvular pathology (aortic stenosis, n = 48; aortic regurgitation, n = 20; mitral stenosis, n = 21; and mitral regurgitation, n = 36) and diagnostically insufficient Doppler signal were enrolled in this multicenter study. The severity of valvular pathology was graded on a four-point scale using unenhanced and contrast-enhanced Doppler echocardiography as well as cardiac catheterization. Agreement with cardiac catheterization findings increased from 63% using the unenhanced examination to 73% using the contrast-enhanced Doppler examination. Grading was possible in all patients using SHU 508 A, whereas the unenhanced Doppler examination remained inconclusive in six patients. The weighted kappa coefficient between contrast-enhanced Doppler and cardiac catheterization for all diagnoses was 0.76 as compared to 0.68 between unenhanced Doppler and cardiac catheterization. Agreement was especially improved in aortic stenosis (kappa 0.69 unenhanced vs 0.81 contrast-enhanced) and in aortic regurgitation (kappa 0.45 unenhanced vs 0.75 contrast-enhanced). Patients with mitral stenosis and mitral regurgitation experienced less improvement. CONCLUSIONS: In case of an inconclusive unenhanced Doppler echo study, the administration of a left heart contrast agent should be considered. SHU 508 A is especially useful in improving the severity grading of aortic stenosis and aortic regurgitation, while grading of mitral stenosis and mitral regurgitation is less improved.

Evaluation of the SOFA score: a single-center experience of a medical intensive care unit in 303 consecutive patients with predominantly cardiovascular disorders. Sequential Organ Failure Assessment.

OBJECTIVE: To evaluate the use of the Sequential Organ Failure Assessment (SOFA) score, the total maximum SOFA (TMS) score, and a derived variable, the deltaSOFA (TMS score minus total SOFA score on day 1) in medical, cardiovascular patients as a means for describing the incidence and severity of organ dysfunction and the prognostic value regarding outcome. DESIGN: Prospective, clinical study. SETTING: Medical intensive care unit in a university hospital. PATIENTS: A total of 303 consecutive patients were included (216 men, 87 women; mean age 62 +/- 12.6 years; SAPS II 26.2 +/- 12.7). They were evaluated 24 h after admission and thereafter every 24 h until ICU discharge or death between November 1997 and March 1998. Readmissions and patients with an ICU stay shorter than 12 h were excluded. MAIN OUTCOME MEASURE: Survival status at hospital discharge, incidence of organ dysfunction/failure. INTERVENTIONS: Collection of clinical and demographic data and raw data for the computation of the SOFA score every 24 h until ICU discharge. MEASUREMENTS AND MAIN RESULTS: Length of ICU stay was 3.7 +/- 4.7 days. ICU mortality was 8.3% and hospital mortality 14.5%. Nonsurvivors had a higher total SOFA score on day 1 (5.9 +/- 3.7 vs. 1.9 +/- 2.3, p < 0.001) and thereafter until day 8. High SOFA scores for any organ system and increasing number of organ failures (SOFA score > or = 3) were associated with increased mortality. Cardiovascular and neurological systems (day 1) were related to outcome and cardiovascular and respiratory systems, and admission from another ICU to length of ICU stay. TMS score was higher in nonsurvivors (1.76 +/- 2.55 vs. 0.58 +/- 1.39, p < 0.01), and deltaSOFA/total SOFA on day 1 was independently related to outcome. The area under the receiver-operating characteristic curve was 0.86 for TMS, 0.82 for SOFA on day 1, and 0.77 for SAPS II. CONCLUSIONS: The SOFA, TMS, and deltaSOFA scores provide the clinician with important information on degree and progression of organ dysfunction in medical, cardiovascular patients. On day 1 both SOFA score and TMS score had a better prognostic value than SAPS II score. The model is closely related to outcome and identifies patients who are at increased risk for prolonged ICU stay.

[Improved endocardial border delineation during dobutamine stress echocardiography using the left heart contrast medium BY 963]. / Verbesserte Endokarderkennung der Dobutamin-Belastungsechokardiographie durch Einsatz des Linksherzkontrastmittels BY 963.

UNLABELLED: The interpretation of induced wall motion abnormalities during dobutamine stress echocardiography is affected in the case of impaired image quality. In 48 consecutive patients (mean age 62 +/- 9 years, 32 males, 16 females) with suspected coronary disease undergoing coronary angiography, the transpulmonary contrast agent BY 963 was given i.v. as bolus during dobutamine stress echocardiography (10-40 micrograms kg min, plus max. 1 mg atropine) to analyze improvements in endocardial border delineation. For each of the 16 segments of the left ventricle, the endocardial border delineation was evaluated. Using BY 963 the average number of non-evaluable segments decreased by 58% from 5.2% to 2.2% at rest (p = 0.008) and by 56% from 5.9% to 2.6% at maximal stress (p = 0.003) as compared to the non-contrast study for all patients. In patients with impaired image quality, defined as at least 1 non-evaluable segment at rest without contrast enhancement (N = 14), the number of non-evaluable segments decreased from 19.2% to 8.2% (p = 0.004) at rest and from 19.2% to 9.6% (p = 0.006) at maximal stress. The greatest decrease of non-evaluable segments was seen in the lateral and anterior segments of the apical views (maximum of 80%). The improved endocardial border delineation resulted in an improved agreement between two observers in the interpretation of the dobutamine stress echocardiograms as positive or negative (kappa = 0.38 without contrast, kappa = 0.58 with contrast). Contrast application resulted in a slight improvement of diagnostic accuracy of dobutamine stress echocardiography in the detection of angiographically proven significant coronary artery disease. CONCLUSION: In patients with impaired endocardial border delineation the use of the echo contrast agent BY 963 reduces the number of non-evaluable segments. Improvement of endocardial delineation is greatest for lateral and anterior segments in the apical views.

Assessment of myocardial reperfusion by intravenous myocardial contrast echocardiography and coronary flow reserve after primary percutaneous transluminal coronary angioplasty [correction of angiography] in patients with acute myocardial infarction.

BACKGROUND: This study investigated whether the extent of perfusion defect determined by intravenous myocardial contrast echocardiography (MCE) in patients with acute myocardial infarction (AMI) treated by primary percutaneous transluminal coronary angioplasty (PTCA) relates to coronary flow reserve (CRF) for assessment of myocardial reperfusion and is predictive for left ventricular recovery. METHODS AND RESULTS: Twenty-five patients with first AMI underwent intravenous MCE with NC100100 with intermittent harmonic imaging before PTCA and after 24 hours. MCE before PTCA defined the risk region and MCE at 24 hours the "no-reflow" region. The no-reflow region divided by the risk region determined the ratio to the risk region. CFR was assessed immediately after PTCA and 24 hours later. Left ventricular wall motion score indexes were calculated before PTCA and after 4 weeks. CFR at 24 hours defined a recovery (CFR >/=1.6; n=17) and a nonrecovery group (CFR <1.6; n=8). Baseline CFR did not differ between groups. MCE ratio to the risk region was smaller in the recovery group compared with the nonrecovery group (34+/-49% vs 81+/-46%, P=0.009). A ratio to the risk region of

Non-contrast second harmonic imaging improves interobserver agreement and accuracy of dobutamine stress echocardiography in patients with impaired image quality.

OBJECTIVE: To examine the influence of second harmonic imaging during dobutamine echocardiography on regional endocardial visibility, interobserver agreement in the interpretation of wall motion abnormalities, and diagnostic accuracy in patients with reduced image quality. DESIGN: Blinded comparison. SETTING: Tertiary care centre. PATIENTS: 103 consecutive patients with suspected coronary artery disease and impaired transthoracic image quality (>/= 2 segments with poor endocardial delineation). METHODS: Fundamental and second harmonic imaging were performed at each stage of a dobutamine stress echocardiography. Coronary angiography was undertaken within three weeks of dobutamine echocardiography in 75 patients. MAIN OUTCOME MEASURES: Evaluation of regional endocardial visibility (scoring from 0 = poor to 2 = good) and of segmental wall motion abnormalities for both modalities separately. A second blinded examiner analysed 70 studies to determine interobserver agreement. RESULTS: Mean (SD) visibility score for all segments was 1.2 (0.4) using fundamental imaging and 1.7 (0.2) using second harmonic imaging at rest (p < 0.001), and 1.1 (0.4) v 1.6 (0.3), respectively, at peak dobutamine dose (p < 0.001). The average number of segments with poor endocardial visibility was lower for second harmonic than for fundamental imaging (0.6 (1.1) v 3.8 (2.6) at rest, p < 0.001; 0.9 (1.3) v 4.3 (2.9) at peak dose, p < 0.001). Improvement was most pronounced in all lateral and anterior segments. The kappa value for identical study interpretation increased from 0. 40 to 0.69 (p < 0.05). Sensitivity for the diagnosis of coronary artery disease was 64% using fundamental imaging versus 92% using harmonic imaging (p < 0.001), while specificity remained unchanged at 75% for both imaging modalities. CONCLUSIONS: Second harmonic imaging enhances endocardial visibility during dobutamine echocardiography. Consequently, interobserver agreement on stress echocardiography interpretation and diagnostic accuracy are significantly improved compared to fundamental imaging. Thus, in difficult to image patients, dobutamine echocardiography should be performed using second harmonic imaging.

Transthoracic echocardiography using second harmonic imaging: diagnostic alternative to transesophageal echocardiography for the detection of atrial right to left shunt in patients with cerebral embolic events.

OBJECTIVES: We sought to evaluate whether transthoracic contrast echocardiography using second harmonic imaging (SHI) is a diagnostic alternative to transesophageal contrast echocardiography (TEE) for the detection of atrial right to left shunt. BACKGROUND: Paradoxic embolism is considered to be the major cause of cerebral ischemic events in young patients. Contrast echocardiography using TEE has proven to be superior to transthoracic echocardiography (TTE) for the detection of atrial shunting, SHI is a new imaging modality that enhances the visualization of echocardiographic contrast agents. METHODS: We evaluated 111 patients with an ischemic cerebral embolic event for the presence of atrial right to left shunt using an intravenous (IV) contrast agent in combination with three different echocardiographic imaging modalities: 1) TTE using fundamental imaging (FI); 2) TTE using SHI; and 3) TEE. The severity of atrial shunting and the duration of contrast visibility within the left heart chambers were evaluated for each imaging modality. Image quality was assessed separately for each modality by semiquantitative scoring (0 = poor to 3 = excellent). Presence of atrial right to left shunt was defined as detection of contrast bubbles in the left atrium within the first three cardiac cycles after contrast appearance in the right atrium either spontaneously or after the Valsalva maneuver. RESULTS: A total of 57 patients showed evidence of atrial right to left shunt with either imaging modality. Fifty-one studies were positive with TEE, 52 studies were positive with SHI, and 32 were positive with FI (p<0.001 for FI vs. SHI and TEE). The severity of contrast passage was significantly larger using SHI (61.6+/-80.2 bubbles) compared to FI (53.7+/-69.6 bubbles; p<0.005 vs. SHI) but was not different compared to TEE (43.9+/-54.3 bubbles; p = NS vs. SHI). The duration of contrast visibility was significantly longer for SHI (17.4+/-12.4 s) compared to FI (13.1+/-9.7 s; p<0.001) and TEE (11.9+/-9.6 s; p<0.02). Mean image quality improved significantly from FI (1.5+/-0.8) to SHI (2.0+/-0.8; p<0.001 vs. FI) and TEE (2.5+/-0.7; p<0.001 vs. SHI). CONCLUSIONS: In combination with IV contrast injections, TEE and SHI have a comparable yield for the detection of atrial right to left shunt. Both modalities may miss patients with atrial shunting. In young patients with an unexplained cerebrovascular event and no clinical evidence of cardiac disease, a positive SHI study may obviate the need to perform a TEE study to search for cardiac sources of emboli.

Extent and severity of test positivity during dobutamine stress echocardiography. Influence on the predictive value for coronary artery disease.

AIMS: Recent studies have evaluated the diagnostic accuracy and predictive value of dobutamine echocardiography without considering the additional information implied by the magnitude of induced wall motion abnormalities. We sought to evaluate the positive predictive value of dobutamine echocardiography for coronary artery disease from the extent and severity of the induced wall motion abnormality. In addition, we intended to determine factors associated with false-negative dobutamine echocardiography. METHODS AND RESULTS: Two hundred and eighty-three consecutive patients with suspected coronary artery disease underwent dobutamine echocardiography (up to 40 microg x kg(-1) x min(-1)+atropine up to 1 mg) and coronary angiography. The number of segments and the degree of deterioration were used to describe the extent and severity of induced wall motion abnormality. Analysis of clinical, procedural and echocardiographic variables was performed to determine factors associated with false-negative results. The positive predictive value of dobutamine echocardiography increased from 85% to 90%, 94% and 94% with deterioration of wall motion by one grade in >/=1, >/=2, >/=3 and >/=4 segments, respectively (P<0.05). Deterioration of wall motion by two grades in one segment had a positive predictive value of 96% as compared to 85% for deterioration by only one grade in one segment (P<0.05). Patients with false-negative test results received atropine more frequently (28% vs 13%, odds ration [OR]=3.87, 95% confidence interval [CI]=1.54-9.75, P=0.028) than patients with a correct positive result. However, angina (15 vs 37%, OR=0.26, 95% CI=0.09-0.71, P=0.010), ECG changes during dobutamine stress (15% vs 35%, OR=0.49, 95% CI 0.19-1.25, P=0.014) and high image quality (OR 1.59, 95% CI 1.07-2.37, P=0.015) were less frequent. The sensitivity of dobutamine echocardiography increased from 67% to 71% and 86% (P<0.05) with increasing achieved maximal heart rate (<75%, 75-85% and >85% of maximal heart rate). CONCLUSION: The positive predictive value of dobutamine echocardiography increases significantly as the extent and severity of induced wall motion abnormality increases. Thus, the degree of test positivity should be reported in clinical practice. Despite high pharmacological drug doses, the haemodynamic response may still be insufficient in some patients to induce myocardial ischaemia, resulting in false-negative dobutamine echo tests. To maximize the sensitivity of dobutamine echocardiography, the highest haemodynamic stress level, with a heart rate above 85% of the predicted heart rate, should be reached.

Effects of lovastatin on progression of non-dilated and dilated coronary segments and on restenosis in patients after PTCA. The cholesterol lowering atherosclerosis PTCA trial (CLAPT).

OBJECTIVES: The Cholesterol Lowering Atherosclerosis PTCA Trial (CLAPT) is a prospective, randomized trial with blinded angiographic end-points to assess the effect of 2-year's treatment with lovastatin initiated 4 weeks prior to PTCA, compared to usual care on non-dilated coronary segments and on dilated coronary lesions in male patients with total cholesterol between 200 and 300 mg. dl(-1)who underwent elective PTCA. METHODS AND RESULTS: Two hundred and twenty six patients were randomized 4 weeks prior to PTCA to special care (diet plus lovastatin n=112) or usual care (diet; n=114). One hundred and ninety-nine patients underwent PTCA at baseline and were finally included in the study. Quantitative coronary angiographic assessment was performed on blinded cinefilms at baseline (PTCA) and repeated after 4 and 24 months in 91% and 81% of the patients. The primary end-point was a change in the mean segment diameter of non-dilated segments. The mean lovastatin dose was 33 mg. day(-1). Total- and LDL-cholesterol decreased by 21% and 29% in the special care group and by 7% and 11% in the usual care patients. After 2 years, the mean segment diameter of non-dilated segments decreased by 0.03 mm in the usual care group and 0.004 mm in the special care group (P=0.27). The decrease in the mean segment diameter of dilated lesions was 0.17 mm (usual care) and 0.06 mm (special care) (P=0.04) after 4 months; 0.16 mm (usual care) and 0. 002 mm (special care) after 24 months, respectively (P=0.05). In both groups, the mean segment diameter of dilated lesions increased between 4 and 24 months after PTCA compared to a decrease in mean segment diameter of non-dilated segments (P<0.05). Restenosis (>50% diameter stenosis at follow-up) occurred in 28.4% of usual care and 22.2% of special care patients (P=0.17). CONCLUSIONS: Lovastatin reduced the progression of dilated lesions in men with elective PTCA. Independent of treatment allocation, the dilated lesions regressed and the non-dilated segments progressed during the study follow-up. Four weeks of pre-treatment with lovastatin did not influence the rate of restenosis. Lovastatin had no statistically significant effect on non-dilated segments.

[Overestimation of regurgitation velocities of intact mechanical heart valve prostheses and other small orifices with 10 mm2 Doppler echocardiography]. / Uberschätzung von Regurgitationsgeschwindigkeiten an intakten mechanischen Herzklappenprothesen und anderen kleineren Offnungen unter 10 mm2 mittels der kontinuierlichen Dopplerechokardiographie.

A systematic evaluation of the accuracy of continuous wave echo Doppler measurements across prosthetic valve leakages and regurgitant lesions has not been performed. Continuous echo Doppler velocity measurements in an in vitro, steady flow model, across the leaks of 12 intact mechanical prostheses and across six circular nozzles (area, 0.5-20 mm2) at pressure drops between 30 and 105 mm Hg were analyzed and compared to the velocities predicted by the modified Bernoulli equation. Laser Doppler anemometry of flow velocities through the nozzles was performed in addition. Despite excellent correlation, there was substantial overestimation of "Bernoulli predicted"-velocities by echo Doppler in the prosthetic leaks (mean +12.3 +/- 9.4%; range, 90.3-143.4%). Also in nozzles < or = 10 mm2, but not in those > 20 mm2, an overestimation of the "Bernoulli predicted"-velocities was observed (mean +6.2 +/- 2%). Laser Doppler anemometry of flow velocities through the nozzles showed slightly lower values than predicted by the Bernoulli equation. This effect apparently is due to transit time effects leading to spectral broadening and should be taken into account when using echo Doppler measurements in very small (< 10 mm2) orifices, such as mild to moderate regurgitant lesions and prosthetic valve leakage.

Overestimation of flow velocity through leaks in mechanical valve prostheses and through small orifices by continuous-wave Doppler.

The reliability of continuous-wave Doppler flow velocity measurements through small regurgitant lesions, such as in prosthetic leakage, has not been systematically analyzed. To evaluate the accuracy of continuous-wave Doppler in prosthetic valve leakage and small orifices in an in vitro, steady-flow model-flow velocities through the leaks of twelve intact mechanical prostheses and through six circular nozzles (area 0.5 to 20 mm2) were measured at pressure drops between 30 and 105 mm Hg. These results were compared with those predicted by the modified Bernoulli equation. Laser Doppler anemometry of flow velocities through the nozzles was also performed. Despite high correlation, there was substantial overestimation of Bernoulli predicted velocities by echo Doppler in the prosthetic leaks (mean +12.3% +/- 9.4%; range 90.3% to 143.4%). In the nozzles < or = 10 mm2, but not in the largest (20 mm2) nozzle, there was also overestimation of the Bernoulli predicted velocities (mean +6.2% +/- 2%). Laser Doppler anemometry of flow velocities through the nozzles showed slightly lower values than predicted by the Bernoulli equation. Thus, continuous-wave echo Doppler overestimates flow velocities through small orifices. This apparently is, at least in part, due to transit time effects and should be taken into account when using echo Doppler in small (< 10 mm2) orifices, such as in mild to moderate regurgitant lesions and prosthetic valve leakage.

Detection of abnormal aortic elastic properties in asymptomatic patients with Marfan syndrome by combined transoesophageal echocardiography and acoustic quantification.

OBJECTIVE: To evaluate the potential value of transoesophageal echocardiography combined with automated border detection and acoustic quantification for the assessment of elastic properties of the thoracic aorta in patients with Marfan syndrome. SUBJECTS: 16 patients with Marfan syndrome and 12 age matched normal controls. METHODS: Transoesophageal echocardiography was performed in all subjects. Minimum and maximum diameters of the descending thoracic aorta were obtained from M mode images and acoustic quantification was used for the on-line evaluation of cross sectional aortic area and peak positive area changes over time. Compliance, distensibility, and stiffness index were calculated using M mode data and non-invasively measured blood pressure and were compared with the indices derived from acoustic quantification. RESULTS: Aortic dimensions normalised for body surface area were not statistically different between patients and normal controls, but there were significant differences for all elasticity indices except compliance. Marfan patients had a lower distensibility [4.2 (SD 1.8) v 5.8 (2.1) cm2/dyn, P < 0.05] and a higher stiffness index [9.7 (3.0) v 7.1 (1.8), P < 0.05]. The dynamic indices derived from the acoustic quantification were significantly smaller in Marfan patients [peak positive area change: 5.1 (1.0) v 7.7 (1.7) cm2/s; P < 0.001; and normalised peak positive area change: 2.5 (1.2) v 4.0 (0.8) cm2/s respectively, P < 0.001] and were suitable to discriminate between normal and abnormal elastic properties. CONCLUSIONS: In Marfan syndrome elastic properties of the descending aorta are significantly different from normal controls, even in the absence of vessel dilatation. In addition to established static indices, indices derived from acoustic quantification reflect dynamic changes of the cross sectional area for the evaluation of regional vessel mechanics. The on-line assessment of peak positive area change allows differentiation from normal individuals and may be more accurate than standard M mode measurements.

[The management of adolescents and adults with congenital heart defects: 3 years experiences with interdisciplinary consultation]. / Die Betreuung von Adoleszenten und Erwachsenen mit angeborenem Herzfehler: 3 Jahre Erfahrungen mit einer interdisziplinären Sprechstunde.

UNLABELLED: Since September 1991, 204 patients (pts), 109 male and 95 female, mean age 27.3 +/- 10.6 years, were followed in a newly established interdisciplinary outpatient clinic combining both adult and pediatric cardiologists. 61 pts predominantly presented with left-to-right shunt congenital heart disease (CHD), 32 with valvar CHD, 20 with aortic coarctation, 23 with complex acyanotic, and 49 with cyanotic CHD. The population included 19 pts with Marfan syndrome. 106 pts had had previous cardiac surgery, 32 of them with up to three reoperations. Deficits and needs in medical and social care were analyzed in 100 pts using a standardized questionnaire at the time of first examination: One-third of pts were not or only incompletely informed about their CHD, previous surgical procedures and need for antibiotic prophylaxis of endocarditis. Only a minority of pts had had vocational advice (34%) or counseling concerning contraception (40%) or pregnancy (30%). Cardiac catheterization was performed in 37 pts (18%) after being first seen in our outpatient clinic, followed by a primary surgical intervention in 19 and reoperation in eight cases. Overall, 30 pts (15%) underwent surgery (28) or interventional procedures (one closure of the arterial duct, one AV node ablation after Mustard-operation) as a consequence of admission to our unit. Successful late Fontan operations were performed in four adults aged 21 to 35 years. There was 1/30 postoperative death (M. Ebstein, thrombosis of the mechanical prosthesis). The population includes five pts with severe pulmonary vascular disease (one waiting for lung transplantation) and two pts with pulmonary artery arborisation malformations not amenable to surgery. CONCLUSION: In a population of 204 adolescents and adults with CHD, we clearly found deficits in medical and social care and, in addition, an unexpected high percentage of necessary invasive investigations (18%) and surgical or interventional procedures (15%). Interdisciplinary management of these patients is mandatory combining the special facilities of adult and pediatric cardiologists.

Enzyme-linked immunoassay for detection of Listeria monocytogenes in dairy products, seafoods, and meats: collaborative study.

A collaborative study was conducted to evaluate Listeria-Tek, an enzyme-linked immunosorbent assay (ELISA) for detection of Listeria monocytogenes and other Listeria spp. in foods. The present ELISA method was compared to the U.S. Food and Drug Administration culture method for detection of L. monocytogenes in dairy products and seafoods and to the U.S. Department of Agriculture Food Safety and Inspection Service method for detection of L. monocytogenes in meats. Replicate samples of 6 food types (frankfurters, roast beef, Brie cheese, 2% milk, raw shrimp, and crab meat) inoculated with L. monocytogenes and uninoculated control samples were analyzed by the collaborators. L. monocytogenes was identified in 593 samples by the ELISA method and in 574 samples using culture procedures. Identical results were obtained for 506 positive samples and 419 negative samples using the ELISA and culture methods for an overall agreement rate of 85.6%. The enzyme-linked immunoassay for detection of L. monocytogenes in dairy, seafood, and meat products has been adopted first action by AOAC INTERNATIONAL.