Orlando Campos

Safety of Dobutamine-Atropine Stress Echocardiography: A Prospective Experience of 4033 Consecutive Studies ☆ ☆☆

Dobutamine-atropine stress echocardiography (DASE) is an established method and has been shown to be accurate for the detection of coronary artery disease. Still, there are few large clinical studies that analyze the safety of DASE in general or the safety of performing it on an ambulatory basis. Most studies use a target heart rate as the primary end point regardless of whether asymptomatic ischemia occurs. Such studies have shown a serious cardiac event rate of approximately 0.3%. We prospectively studied 4,033 consecutive patients on an ambulatory basis and in the hospital with the use of DASE from July 1991 to December 1998. All tests were performed by an experienced physician, and all clinical and DASE data were stored in a large database organized at the beginning of the study. Dobutamine was infused in scalar doses of 5, 10, 20, 30, and 40 microg/kg per minute in 3-minute stages. Development of a new wall motion abnormality, achievement of 85% of target heart, and end of the DASE infusion protocol were used as an end point. If 85% of the target heart rate was not achieved, atropine was infused up to 1 mg in the absence of myocardial ischemia, which was used in 1,280 studies. There were 3,645 diagnostic tests, and 388 (10%) were found to be nondiagnostic. This result was due to poor image quality in 115 (3%), end of protocol in negative-submaximal examinations in 124 (3%), and limiting side effects in 149 (4%). Thirty-seven percent of the tests showed positive results for myocardial ischemia. Major test-related cardiac complications occurred in 10 (0.25%) patients and included 1 ventricular fibrillation, 1 case of myocardial infarction, and 8 cases of sustained ventricular tachycardia. Atropine poisoning was observed in 5 (0.12%) patients. No deaths occurred as a direct or indirect consequence of DASE. We conclude that dobutamine-atropine stress echocardiography is a reasonably safe method for detection of coronary artery disease in the hospital or in an ambulatory basis. The use of new wall motion abnormality as 1 of the end points may prevent further ischemia-related complications.

Physiologic multivalvular regurgitation during pregnancy: a longitudinal Doppler echocardiographic study☆

Valvular function, assessed by Doppler technique, has not been extensively investigated during normal pregnancy. To prospectively study this feature, 18 normal pregnant women were followed during their pregnancies and puerperium, with serial clinical and pulsed-continuous Doppler echocardiographic examinations. In four gestational periods and the puerperium, we analysed: (a) ventricular and atrial dimensions, as well as valve annular diameters; (b) prevalence and characteristics of trivial valvular regurgitations. During pregnancy, slight but significant increases of the four cardiac chamber dimensions and valve annular diameters were observed, except for the aortic ring. The prevalence of physiologic valvular regurgitation in early pregnancy (mitral, 0%; tricuspid, 38.9%; pulmonary, 22.2%; aortic, 0%), was similar to a control group of 18 healthy non-pregnant women. As pregnancy evolved, there was a progressive and significant increase of multivalvular regurgitation, maximal at full-term (mitral, 27.8%; tricuspid, 94.4%; pulmonary, 94.4%, P < 0.05 vs. early pregnancy). Aortic regurgitation was not detected in any stage of pregnancy. In the puerperium, mitral regurgitation resolved, but tricuspid and pulmonary regurgitation were still significantly prevalent (83.3% and 66.7%, respectively, P < 0.05 vs. early pregnancy). It is concluded that physiologic multivalvular regurgitation is frequent in pregnancy, mainly involving right-sided valves in late gestational periods, occasionally persisting in the early puerperium. Chamber enlargement, valve annular dilatation, and increased prevalence of trivial valve regurgitation are time-related events during normal pregnancy, resulting from a reversible cardiac remodeling process induced by physiologic volume overload. These aspects should be considered for a correct interpretation of Doppler echocardiographic findings in pregnant women with suspected heart disease.

Impact of continuous positive airway pressure treatment on left atrial volume and function in patients with obstructive sleep apnoea assessed by real-time three-dimensional echocardiography

Background: Obstructive sleep apnoea (OSA) has been reported as a predictor of left ventricle (LV) diastolic dysfunction and left atrium (LA) remodelling. The aim of this study is to evaluate the impact of OSA treatment with a continuous positive airway pressure device (CPAP) on the LA volume and function, as well as on the LV diastolic function. Methods: In total, 56 OSA patients were studied. All patients underwent real-time three-dimensional (RT3DE) and two-dimensional echocardiogram with tissue Doppler evaluation in order to estimate LA volumes, function and LV diastolic performance. A total of 30 patients with an apnoea-hypopnoea index greater than 20 were randomly selected to receive sham CPAP (n = 15) or effective CPAP (n = 15) for 24 weeks. They underwent echo examination on three different occasions: at baseline, after 12 weeks and 24 weeks of CPAP or sham CPAP. Results: In the effective CPAP group we observed the following changes from the baseline to the 24-week echo evaluation: (a) a reduction in the E/E′ ratio (10.3 (1.9) to 7.9 (1.3), p = 0.03); (b) an increase in the LA passive emptying fraction (28.8% (11.9%) to 46.8% (9.3%), p = 0.01); and (c) a reduction in the LA active emptying fraction (42.7% (11.5%) to 25.7 (15.7), p<0.01). In the sham group, there were no changes from the baseline to the 24-week echo. We found a positive correlation between 24 week/baseline LA active emptying volume and 24 week/baseline E/E′ ratios (r = 0.40, p<0.05) and a negative correlation between 24 week/baseline LA passive emptying volume and 24 week/baseline E/E′ ratios (r = −0.53, p<0.05). No significant changes were found on LA total emptying fraction. Conclusion: CPAP improved LV diastolic function and LA passive emptying, but not LA structural variables in OSA patients. Trial registration number: NCT00768807.

Importance of intraoperative transesophageal echocardiography during coronary artery surgery without cardiopulmonary bypass

The goal of this study was to assess left ventricular segmental wall motion (SWM) abnormalities during coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB), and its impact on the immediate postoperative outcome. Transesophageal echocardiography was used intraoperatively in 27 patients (mean age 57 years) who had CABG without CPB. Images obtained with a 5-MHz biplane transesophageal echocardiographic probe in the transgastric and transesophageal planes were recorded before, during, and after 48 coronary artery clampings for saphenous vein or internal mammary artery anastomosis. Transthoracic echocardiography was performed 1 day before surgery and on the seventh postoperative day. During the 48 coronary artery clampings, 31 (64%) new SWM abnormalities were found. At the time of chest closure, complete recovery occurred in 16 (50%) segments, partial recovery in 10 (33%), and no recovery in 5 (17%). On the seventh postoperative day the new SWM abnormalities persisted in all 5 segments without recovery at the end of the surgery and in 2 of 10 (20%)segments with partial recovery (group 1). Group 1 had higher variation on the echocardiographic point score index between the beginning and end of surgery, higher enzymatic levels, more ST-T changes on the electrocardiogram, and more clinical problems than group 2 (patients without new SWM abnormalities on the seventh postoperative day) (P < .05). We concluded that new SWM abnormalities of the left ventricle occur during CABG without CPB as assessed by intraoperative transesophageal echocardiography. Persistence of these abnormalities at the end of surgery may be a predictor of SWM dysfunction and clinical problems in the immediate postoperative period.

Performance of two-dimensional Doppler echocardiography for the assessment of infarct size and left ventricular function in rats

Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes), infarct size (percentage of the arc with infarct on 3 transverse planes), systolic function by the change in fractional area, and diastolic function by mitral inflow parameters. The histologic measurement of myocardial infarction size was similar to the echocardiographic method. Myocardial infarct size ranged from 4.8 to 66.6% when determined by histology and from 5 to 69.8% when determined by echocardiography, with good correlation (r = 0.88; P < 0.05; Pearson correlation coefficient). Left ventricular diameter and mean diastolic transverse area correlated with myocardial infarct size by histology (r = 0.57 and r = 0.78; P < 0.0005). The fractional area change ranged from 28.5 +/- 5.6 (large-size myocardial infarction) to 53.1 +/- 1.5% (control) and correlated with myocardial infarct size by echocardiography (r = -0.87; P < 0.00001) and histology (r = -0.78; P < 00001). The E/A wave ratio of mitral inflow velocity for animals with large-size myocardial infarction (5.6 +/- 2.7) was significantly higher than for all others (control: 1.9 +/- 0.1; small-size myocardial infarction: 1.9 +/- 0.4; moderate-size myocardial infarction: 2.8 +/- 2.3). There was good agreement between echocardiographic and histologic estimates of myocardial infarct size in rats.

Doppler Echocardiography During Pregnancy: Physiological and Abnormal Findings.

Despite continuous improvements in diagnostic cardiology techniques, echocardiography remains the cornerstone for noninvasive cardiovascular assessment of the pregnant woman with heart disease or suspected cardiac abnormality. Reversible physiological cardiac remodeling of pregnancy associated with changes in valve patency or transvalvular flow pattern can be suitably assessed by the complementary use of quantitative pulsed‐ and continuous Doppler and qualitative color Doppler technology. These techniques are also useful for a better understanding of the pathophysiology of the hemodynamic consequences of fixed valve stenosis during pregnancy with respect to the labile nature of gradients resulting from variable loading conditions as occurs during pregnancy. Recent and specific areas of clinical use including cardiac output estimation, contrast echocardiography minimizing radioscopy during cardiac catheterization, and transesophageal echocardiography for selection of patients with mitral stenosis suitable for percutaneous catheter valvotomy illustrate the large spectrum of capabilities of this versatile method during pregnancy.

Structural and functional characteristics of rat hearts with and without myocardial infarct. Initial experience with doppler echocardiography

OBJECTIVE To assess by Doppler echocardiography the structural and functional alterations of rat heart with surgical induced extensive myocardial infarction. METHODS Five weeks after surgical ligature of the left coronary artery, 38 Wistar-EPM rats of both sexes, 10 of them with extensive infarction, undergone anatomical and functional evaluation by Doppler echocardiography and then euthanized for anatomopathological analysis. RESULTS Echocardiography was 100% sensible and specific to anatomopathological confirmed extensive miocardial infarction. Extensive infarction lead to dilatation of left ventricle (diastolic diameter: 0.89 cm vs.0.64 cm; systolic: 0. 72 cm vs. 0.33 cm) and left atrium (0.55 cm vs. 0.33 cm); thinning of left ventricular anterior wall (systolic: 0.14 cm vs. 0.23 cm, diastolic: 0.11 cm vs. 0.14 cm); increased mitral E/ A wave relation (6.45 vs. 1.95). Signals of increased end diastolic ventricle pressure, B point in mitral valve tracing in 62.5% and signs of pulmonary hypertension straightening of pulmonary valve (90%) and notching of pulmonary systolic flow (60%) were observed in animals with extensive infarction. CONCLUSION Doppler echocardiography has a high sensitivity and specificity for detection of chronic extensive infarction. Extensive infarction caused dilatation of left cardiac chambers and showed in Doppler signals of increased end diastolic left ventricular pressure and pulmonary artery pressure.

Cardioprotective effect of dexrazoxane during treatment with doxorubicin: A study using low-dose dobutamine stress echocardiography

To assess the late cardioprotective effect of dexrazoxane associated with doxorubicin during treatment of osteosarcoma by means of low‐dose dobutamine stress echocardiography (LDDSE) in non‐relapsed asymptomatic children and teenagers.

The Influence of Left Ventricular Size and Global Function on Regional Myocardial Contraction and Relaxation in an Adult Population Free of Cardiovascular Disease: A Tagged CMR Study of the MESA Cohort

The purpose of this study is to evaluate the relationship between LV structure and function with regional myocardial function in participants of the Multi-Ethnic Study of Atherosclerosis, which is a prospective study including 4 ethnic groups free from clinical cardiovascular disease. Peak systolic strain (Ecc) and regional strain rates (SRS and SRE) were calculated by harmonic phase from tagged CMR of 1100 participants. The relationships of ejection fraction (EF), end-systolic volume (ESV) and end-diastolic volume (EDV) with Ecc and strain rate were studied before and after adjustment for cardiovascular risk factors. Direct linear relationships between EF and regional systolic and diastolic functions (Ecc, SRS and SRE) were present in almost all of the regions (p < 0.05, i.e., greater EF, greater Ecc, SRS and SRE). LVESV demonstrated a negative relationship with Ecc and SRS (i.e., greater ESV, lower systolic function, indexed by Ecc and SRS) in all regions (p < or = 0.05). LVEDV was inversely related to systolic function, indexed by SR(S) (p < 0.05) in all regions. In conclusion, LVEF is directly related to systolic myocardial function, indexed as the absolute magnitude of systolic strain and strain rate. In addition, left ventricular size, indexed as end-diastolic and end-systolic volumes are inversely related to absolute systolic myocardial strain rate (SRS). These results are crucial to the interpretation of strain alterations induced by left ventricular remodeling in early heart failure.

A haemodynamic study of pulmonary hypertension in chronic hypersensitivity pneumonitis

Chronic hypersensitivity pneumonitis is a common fibrotic interstitial lung disease. The prevalence of pulmonary hypertension diagnosed by right heart catheterisation and its cardiopulmonary function findings in patients with chronic hypersensitivity pneumonitis are unknown. Consecutive symptomatic patients with chronic hypersensitivity pneumonitis were prospectively evaluated. All patients were submitted to right heart catheterisation, pulmonary function testing, a 6-min walk test, echocardiography, blood gas determination and N-terminal pro-brain natriuretic peptide analyses. Nonhypoxaemic patients also underwent incremental cardiopulmonary exercise testing. 50 patients underwent right heart catheterisation; 25 (50%) of these had pulmonary hypertension and 22 (44%) had a pre-capillary haemodynamic pattern. The patients with pre-capillary pulmonary hypertension had lower forced vital capacity (mean±sd 50±17% versus 69±22% predicted, p<0.01), carbon monoxide diffusing capacity (37±12% versus 47±14% predicted, p<0.01), arterial oxygen tension (median (interquartile range) 59.0 (47.8–69.3) versus 73.0 (62.2–78.5) mmHg, p<0.01) and saturation after the 6-min walk test (78±8% versus 86±7%, p<0.01). In pre-capillary pulmonary hypertension, oxygen uptake was also lower at the anaerobic threshold (41±11% versus 50±8% predicted, p=0.04) and at peak exercise (12.8±1.6 versus 15.0±2.5 mL·kg−1·min−1, p=0.02). Pre-capillary pulmonary hypertension is common in symptomatic chronic hypersensitivity pneumonitis and is related to interstitial lung disease severity. Additionally, pulmonary hypertension is more prevalent in hypoxaemic patients with impaired lung function and exercise capacity. PH is common in chronic hypersensitivity pneumonitis and is related to interstitial lung disease severity http://ow.ly/uTXXx