Post-exercise heart rate recovery in HIV-positive individuals on highly active antiretroviral therapy. Early indicator of cardiovascular disease?

BACKGROUND: HIV infection and its treatment, specifically protease inhibitor (PI) therapy, have been associated with an increased risk for cardiovascular disease. Heart rate recovery (HRR) following peak exercise is predictive of future cardiovascular events and mortality in the general population. Nothing is known regarding HRR in individuals infected with HIV on highly active antiretroviral therapy (HAART). SUBJECTS AND METHODS: HIV-positive subjects on HAART that included a PI (HIV+PI, n=19), HIV-positive subjects on HAART that did not include a PI (HIV+noPI, n=19) and HIV-seronegative age, gender and body mass index (BMI) matched controls (Cntl, n=15) underwent a graded maximal exercise test on a cycle ergometer to volitional exhaustion. A continuous electrocardiogram was recorded and HRR was monitored every 30 s for 2 min post exercise. RESULTS: HRR at 1.5 and 2 min was significantly delayed in HIV-positive subjects both on and not on PI-based HAART compared with controls (P<0.01). CONCLUSION: HRR is impaired in HIV-positive individuals on HAART, whether or not the HAART includes a PI, compared with age, gender, BMI, and activity level matched HIV-seronegative controls. Abnormal HRR may reflect cardio-autonomic dysfunction and may be an independent risk factor for future cardiac events in HIV-positive individuals that receive HAART.

Cardiac magnetic resonance imaging abnormalities in systemic lupus erythematosus: a preliminary report.

The purpose of this prospective, pilot study was to determine whether differences in myocardial T2 relaxivity can be identified among active systemic lupus erythematosus (SLE) patients with clinically suspected SLE myocarditis, other active SLE patients, inactive SLE patients and age and gender matched controls. Eleven consecutive female patients (six with active SLE and five with inactive SLE), and five age, gender and race matched healthy controls underwent imaging with echocardiography and cardiac magnetic resonance imaging (MRI). Echocardiographic measurements included left ventricular end diastolic (LVEDV) and end systolic volumes (LVESV), and mass (LVM) (all indexed to body mass); ejection fraction and cardiac output. The cardiac MRI measurement was the T2 relaxation time (an index of soft tissue signal, with higher levels suggestive of increased tissue water content). Patients with active SLE had significantly higher LVEDV and LVM than inactive SLE patients and healthy controls, and significantly larger LVESV than healthy controls. Myocardial T2 relaxation times were significantly higher in patients with active SLE compared to those with inactive SLE and to healthy controls, and remained higher even after excluding the two active SLE patients who had clinical myocarditis. The four active SLE patients who underwent repeat cardiac imaging studies after clinical improvement showed normalization of these myocardial abnormalities. The conclusion was that active SLE patients demonstrate abnormalities in myocardial structure manifested by high myocardial T2 relaxation times that normalized after clinical improvement in disease activity. These findings suggest that T2 relaxation values are a sensitive indicator of myocardial disease in patients with SLE and that myocardial T2 relaxation abnormality frequently occur in patients with active SLE, even in the absence of myocardial involvement by clinical criteria.

Tissue Doppler imaging: a useful echocardiographic method for the cardiac sonographer to assess systolic and diastolic ventricular function.

Tissue Doppler imaging (TDI) has evolved to become a useful noninvasive method that can complement other echocardiographic techniques in the assessment of left ventricular myocardial velocities in a variety of clinical conditions. Color 2-dimensional and color M-mode TDI are used for quantification of systolic myocardial velocities during myocardial ischemia at rest and with pharmacologic stress testing. Spectral pulsed TDI can provide measurements of regional systolic and diastolic myocardial velocities, and it is particularly useful in the identification of abnormalities of left ventricular diastolic relaxation. This review summarizes the clinical applications of TDI to promote understanding of its utility in the evaluation of left ventricular myocardial function.

Licensure of the cardiac sonographer: an overview of issues and activities.

The impact of echocardiography on the continuum of cardiovascular health care is well established. Ongoing concerns regarding costs, accessibility, quality, and appropriateness of services rendered by practitioners of echocardiography have prompted various legislative proposals and regulatory policies from government, medical professional groups, and health plans. Specifically, there continues to be a drive to enact law for licensure of sonographers. These activities require continuing advocacy for the profession with active leadership. As part of its mission statement, the American Society of Echocardiography (ASE) states, "ASE strives to be a leader in public policy in order to create a favorable environment for excellence in the practice of echocardiography." As such, the ASE is committed to an increase in their interaction with legislators, payers, and policy makers. This article describes the historical perspective of state, federal, and provincial sonographer licensure issues to provide an understanding of the political perspectives.

Congestive heart failure and the role of two-dimensional Doppler echocardiography: a primer for cardiac sonographers.

Congestive heart failure (CHF) has been an increasing cause of hospitalization, particularly among the elderly population, although the clinical presentation may vary in the individual patient. Two-dimensional and pulsed Doppler echocardiography can be valuable diagnostic methods for the assessment of afflicted patients and can have an impact on patient outcome. The unique advantage of echocardiographic techniques is their ability to characterize left ventricular systolic performance and diastolic filling abnormalities that are commonly present in patients with CHF. This review provides current information the cardiac sonographer can recognize in the assessment of patients with CHF.

The profession of cardiac sonography and the status of professionalization of cardiac sonographers.

The role of the cardiac sonographer has evolved in the profession of cardiac ultrasonography to a level requiring rigorous education, training, and high standards. Although we want to consider ourselves professionals, further efforts are necessary to meet the various criteria conferring such a status. It is essential cardiac sonographers realize these necessary steps to achieve recognition as professionals.

Potential utility of left heart contrast agents in diagnosis of myocardial rupture by 2-dimensional echocardiography.

This case illustrates the use of intravenous injections of a contrast agent during 2-dimensional echocardiography in a patient with myocardial rupture after myocardial infarction. Intravenous injections of echocardiographic contrast agents may have potential use in the identification of intrapericardial hemorrhage after myocardial infarction caused by myocardial rupture or development of ventricular pseudoaneurysm.

The role of transthoracic echocardiography in the management of patients seen in an outpatient cardiology clinic.

Transthoracic two-dimensional (2D) Doppler echocardiography may provide new or additional information in patients, but it is often not known whether the results alter the treatment plan. We investigated whether results of clinically indicated 2D echocardiography were different from the physician's clinical examination or led to changes in management in 200 consecutive outpatients seen in a university-based clinic. A questionnaire was completed by the physician regarding physical findings and treatment plan before 2D echocardiography was performed. After results were known, the physician was asked to report any differences compared with clinical examination or changes in patient management. Most patients (83%) were studied to evaluate left ventricular (LV) or valvular function. 2D echocardiography confirmed clinical assessment in 182 patients (one inadequate 2D echocardiogram) and disclosed a new diagnosis in 17. 2D echocardiography provided additional information, not expected from clinical assessment or history, in 94 patients. Clinical assessment, compared with 2D echocardiography, was concordant in 154 (77%) of 199 patients with regard to LV systolic function but in only 22 (50%) of 44 with valve disease. Alterations in management based on results of 2D echocardiography were instituted in 73 patients (36%), most often manifested by changes in pharmacologic therapy (n = 45; 62%). Results of 2D echocardiography obviated the need for further cardiac evaluation, surgery, or procedures in 30 patients, avoiding additional patient charges of $125,754.00. In contrast, results of 2D echocardiography led to the need for further evaluation, surgery, or procedures in 32 patients, resulting in additional patient charges of $70,860.00. In conclusion, 2D echocardiography provides new or additional information that results in changes in management strategy in one third of patients, and 2D echocardiography offers relative cost savings by avoiding additional procedures.

Right ventricular dysfunction in low output syndrome after cardiac operations: assessment by transesophageal echocardiography.

BACKGROUND: Low output syndrome after cardiac operations is associated with high morbidity and mortality rates. The contribution of right ventricular dysfunction to this syndrome has not been fully characterized. The purpose of this study was to evaluate the utility of transesophageal echocardiography to identify the frequency and the in-hospital mortality from right ventricular dysfunction in patients with this syndrome. METHODS: Seventy-five consecutive patients undergoing transesophageal echocardiography for low output syndrome early after cardiac operations were evaluated. The findings from transesophageal echocardiography were correlated with the type of surgical procedure, cross-clamp time, right heart hemodynamics, and coronary angiography. RESULTS: Right ventricular systolic dysfunction occurred in 36 patients (42%); in 17 patients it was isolated and in 19 patients it occurred in combination with left ventricular dysfunction. Postoperative right ventricular dysfunction was not uniformly associated with important right coronary artery disease or with prolonged ischemic time during cardiopulmonary bypass. Hemodynamic data were not useful to distinguish the group with postoperative right ventricular dysfunction. Patients with right ventricular dysfunction had a high (44%) in-hospital mortality rate. CONCLUSIONS: Right ventricular dysfunction occurs frequently in patients with low output syndrome after cardiac operations and is associated with a high in-hospital mortality rate. Better understanding of the mechanisms causing postoperative right ventricular dysfunction may provide insight for preventing this complication.

Impaired left atrial function after heart transplantation: disparate contribution of donor and recipient atrial components studied on-line with quantitative echocardiography.

BACKGROUND: Because of a lack of noninvasive techniques, left atrial function after orthotopic heart transplantation has not been well characterized. METHODS: Global left atrial performance and the relative contributions of donor and recipient atrial components were assessed with transthoracic echocardiography with on-line automated border detection in 20 patients with normal left ventricular systolic function 1 to 6 years (mean 3.5 +/- 0.3 years [standard error]) after heart transplantation. RESULTS: The mean left atrial area at ventricular end-systole was 22.9 +/- 1.5 cm2, the mean left atrial emptying fraction ([left atrial area at ventricular end-systole--left atrial area at ventricular end-diastole]/left atrial area at ventricular end-systole) was 29.7% +/- 2.6%, and the fractional area change caused by active contraction was 27.8% +/- 3.1%. Compared with controls, patients had larger atria, depressed emptying, and reduced fractional active contraction. Although the recipient to donor area ratio was 3:2, the proportion of atrial emptying (change in area from mid-to-late ventricular diastole divided by the total left atrial change during ventricular diastole) contributed by the recipient component was greatly diminished when compared with that of the donor component (1.4% +/- 3.5% versus 31% +/- 2.7%) (p = 0.0001). CONCLUSIONS: Despite being anatomically smaller, the functional contractile contribution of the donor component dominated atrial emptying. Thus, after heart transplantation, global left atrial function is depressed, predominantly because of dysfunction of the recipient atrial component.

Echocardiographic automatic boundary detection to measure left atrial function after the maze procedure.

Automatic boundary detection (ABD) is a new echocardiographic modality providing continuous on-line measurements of cavitary area throughout the cardiac cycle. The maze procedure is a new surgical intervention designed to restore sinus rhythm and mechanical atrial contraction as a definitive treatment for patients with atrial fibrillations for whom medical therapy has failed. To evaluate whether ABD may define left atrial function in patients after the maze procedure, we obtained pulsed Doppler recordings of mitral inflow velocity and echocardiographic ABD in 25 patients, 6 +/- 2 months after the maze procedure. We measured the left atrial end-systolic cavitary area, mid-diastolic area before atrial contraction, and end-diastolic area (in square centimeters). Left atrial contraction by Doppler was compared with that derived by ABD in patients who underwent the maze procedure and control subjects (n = 13), both qualitatively and quantitatively (atrial filling fraction vs active atrial contraction [ABD] where atrial contraction (in percent) = (mid-diastolic area - end-diastolic area) x 100/(end-systolic area - end-diastolic area in percent]). Restoration of atrial contraction after the maze procedure was detected by Doppler in 19 patients (76%) and by ABD in 21 patients (84%). The atrial filling fraction was 19 +/- 4% in patients compared with values of 34% +/- 8% in control subjects (p < 0.001). By ABD atrial contraction was 20% +/- 6% in patients whereas control subjects exhibited values of 41% +/- 14% p < 0.001). The Doppler-derived atrial filling fraction and ABD-derived atrial contraction were closely correlated (r = 0.91; p < 0.001; y = 0.59x + 8.6). Thus Doppler techniques complemented by ABD provide direct quantitative indexes of left atrial function throughout the cardiac cycle. Although left atrial contraction and filling are reduced after the maze procedure, left atrial function is restored in most patients with a history of atrial fibrillation, and echocardiographic ABD is a sensitive technique for its detection.

Quantitative ultrasonic tissue characterization of myocardium in cyanotic adults with an unrepaired congenital heart defect.

Adults with nonrestrictive ventricular septal defects have chronic hypoxemia that may lead to alterations in myocardial structure and function. Ultrasonic integrated backscatter provides quantitative assessment of myocardial acoustic properties that are altered by myocardial ischemia, fibrosis, and edema. Sixteen patients (age 31 +/- 10 years) with a nonrestrictive ventricular septal defect were studied using 2-dimensional and M-mode echocardiography with integrated backscatter imaging to determine the cyclic variation of integrated backscatter in the right ventricular free wall, ventricular septum, and left ventricular posterior wall. Cyclic variation of integrated backscatter in the right ventricular free wall and interventricular septum in patients was significantly less than that in control subjects (4.1 +/- 0.8 vs 4.9 +/- 1.0 decibels [dB], p = 0.02, and 3.8 +/- 1.2 vs 4.8 +/- 1.1 dB, p = 0.004, respectively). There was no difference between mean cyclic variation of integrated backscatter in the left ventricular posterior wall in patients and that in control subjects (4.7 +/- 1.3 vs 4.8 +/- 1.1 dB, p = NS, respectively). However, values < 4.0 dB were noted in 38% of patients compared with 15% of control subjects. Biventricular systolic function was normal in all but 1 patient. There was no correlation between backscatter and either wall thickness or percent wall thickening from the 3 regions. Histologic analysis of myocardial tissue in 3 patients revealed interstitial and replacement fibrosis. Adults with nonrestrictive ventricular septal defects exhibit alterations in tissue-acoustic properties detectable by integrated backscatter imaging despite preserved systolic function and wall thickening.

Restoration of atrial function after the maze procedure for patients with atrial fibrillation. Assessment by Doppler echocardiography.

BACKGROUND: The purpose of the present study was to evaluate the effects of the maze procedure on atrial function in patients operated on for atrial fibrillation. The maze procedure is a new surgical intervention that is designed to restore sinus rhythm and active mechanical atrial contraction as a definitive treatment for patients with atrial fibrillation. METHODS AND RESULTS: Doppler echocardiographic analysis of mitral and tricuspid inflow as well as pulmonary venous flow velocity was carried out in 46 patients 8 +/- 7 months after the maze procedure, and results were compared with those obtained from 27 age-matched control subjects. To evaluate atrial contraction, we determined the presence of atrial contribution to ventricular filling at the mitral and tricuspid valve levels and measured the percent atrial filling fractions of the left and right atria. To evaluate atrial compliance, we measured the systolic and the systolic-to-diastolic flow velocity ratios of the pulmonary venous inflow. Results were compared with similar measurements obtained from control subjects. Restoration of active atrial contraction was detected in 40 of the 46 patients (87%); right atrial contraction was noted in 38 patients (83%), and left atrial contraction was noted in 28 patients (61%). In patients with active atrial contraction, the percent atrial filling fraction of the right atrium was comparable to that of control subjects (32 +/- 7% versus 33 +/- 8%, P = NS), whereas that of the left atrium was smaller (20 +/- 5% versus 36 +/- 7%, P < .005). In addition, compared with control subjects, pulmonary venous flow in maze patients exhibited a reduced systolic component (17 +/- 4 versus 53 +/- 16 cm/s, P < .001) and decreased systolic-to-diastolic flow velocity ratio (0.3 +/- 0.01 versus 1.1 +/- 0.3, P < .001) and velocity integral ratio (0.3 +/- 0.01 versus 1.3 +/- 0.4, P < .001), all suggesting decreased left atrial filling. CONCLUSIONS: The maze procedure restores active right atrial contraction and improves left atrial contraction in most patients. Obtained measurements suggest decreased left atrial compliance and reduced left atrial contribution to ventricular filling compared with control subjects. Despite the reduced indexes, qualitative restoration of function in either atria should translate in improved atrioventricular synchrony and reduction in thromboembolic events in patients with chronic or paroxysmal atrial fibrillation.

Two-dimensional echocardiographic automatic boundary detection for evaluation of left ventricular function in unselected adult patients.

Recent modifications in two-dimensional echocardiographic imaging include automatic boundary detection (ABD) that permits instantaneous quantification of left ventricular (LV) function. To define its clinical application from different views in consecutive patients (n = 68), we performed both conventional two-dimensional imaging and ABD with lateral gain compensation and compared the ability of each method for visualization of myocardial segments. From each view (short-axis and apical four- and two-chamber), the LV was divided into six wall segments. The short-axis view was obtained successfully in 53 of 68 patients; of the possible 318 segments, 96% were visualized adequately by two-dimensional echocardiography and 89% by ABD. From the four-chamber view, obtained in 63 of 68 patients, visualization of 378 possible segments was 93% by two-dimensional imaging and 86% by ABD, respectively. From the two-chamber view obtained in 58 of 68 patients, the success rate was 88% and 80% (two-dimensional imaging and ABD, respectively). ABD detected LV endocardial/blood borders in all six segments of each view in 73%, 72%, and 72% of cases, concordant with adequate two-dimensional imaging. Discrepancies between two-dimensional imaging and ABD were usually in the short-axis inferior and lateral, four-chamber lateral, and two-chamber anterior segments. There were 46 patients with normal LV wall motion and 22 with wall-motion abnormalities. The average time required to perform ABD was 375 seconds (range 180 to 780 seconds).(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrasonic tissue characterization: integrated backscatter imaging for detecting myocardial structural properties and on-line quantitation of cardiac function.

Quantitative myocardial tissue characterization is being developed as an adjunct to conventional echocardiography to delineate the physical state of myocardium under diverse pathophysiological states. Real-time quantitative integrated backscatter imaging has made possible clinical investigations carried out in the United States, Europe, and Japan in patients with ischemic heart disease, hypertrophic cardiomyopathy, and cardiac allograft rejection, among others. A modification of the imaging processing used for characterization of tissue facilitates automatic detection of endocardial blood interfaces and on-line quantification of ventricular size and function, which has been recently introduced in clinical practice. Further progress and developments in quantitative ultrasonic imaging will place in perspective the clinical use of tissue characterization based on myocardial backscatter.

Echocardiographic characterization of the improvement in right ventricular function in patients with severe pulmonary hypertension after single-lung transplantation.

OBJECTIVES: This study was designed to characterize immediate, early and long-term changes in right ventricular structure and function, as defined by two-dimensional and Doppler echocardiography, after single-lung transplantation in patients with severe pulmonary hypertension. BACKGROUND: Single-lung transplantation has recently been shown to dramatically improve hemodynamics in patients with primary pulmonary hypertension who had unsuccessful medical therapy. METHODS: Fourteen patients with severe pulmonary hypertension who underwent single-lung transplantation were studied with transthoracic and transesophageal two-dimensional and Doppler echocardiography. Right ventricular dimensions were measured in the apical four-chamber view. Right ventricular ejection and acceleration times and peak velocity of tricuspid regurgitation were measured by Doppler study. Results of right heart catheterization were available early (< 3 months) after transplantation in 10 of 13 patients and late after transplantation (6 months to 2 years) in 11 patients. RESULTS: In the early posttransplantation studies, right ventricular dimensions decreased and fractional area change and ejection fraction increased in all patients, but right ventricular wall thickness did not change significantly. Tricuspid regurgitation lessened markedly in all patients. Long-term decreases in right ventricular dimension and improvement in systolic function were sustained. Right ventricular wall thickness significantly decreased compared with the early postoperative value (0.76 +/- 0.1 cm compared with 0.63 +/- 0.14 cm, p < 0.02). CONCLUSIONS: Two-dimensional echocardiography demonstrates sustained improvement in right ventricular function after single-lung transplantation for severe pulmonary hypertension despite severe preoperative dysfunction.