Ivan Barac

Role of Three-Dimensional Echocardiography in Breast Cancer: Comparison With Two-Dimensional Echocardiography, Multiple-Gated Acquisition Scans, and Cardiac Magnetic Resonance Imaging

PURPOSE In patients with breast cancer, the administration of doxorubicin and trastuzumab is associated with an increased risk of cardiotoxicity. Although multiple-gated acquisition (MUGA) scans and two-dimensional transthoracic echocardiography (TTE) are conventional methods for baseline and serial assessment of left ventricular ejection fraction (LVEF) in these patients, little is known about the use of real-time three-dimensional TTE (RT3D TTE) in this clinical setting. The aim of this study was to assess the accuracy of MUGA, 2D TTE, and RT3D TTE for determining LVEF in comparison to cardiac magnetic resonance imaging (CMR). METHODS Between 2007 and 2009 inclusive, 50 female patients with human epidermal growth factor receptor 2-positive breast cancer received adjuvant trastuzumab after doxorubicin. Serial MUGA, 2D TTE, RT3D TTE, and CMR were performed at baseline, 6, and 12 months after the initiation of trastuzumab. RESULTS A comparison of left ventricular end diastolic volume (LVEDV) demonstrated a modest correlation between 2D TTE and CMR (r = 0.64 at baseline; r = 0.69 at 12 months, respectively). A comparison of LVEDV between RT3D TTE and CMR demonstrated a stronger correlation (r = 0.87 at baseline; r = 0.95 at 12 months, respectively). Although 2D TTE demonstrated a weak correlation with CMR for LVEF assessment (r = 0.31 at baseline, r = 0.42 at 12 months, respectively), both RT3D TTE and MUGA showed a strong correlation when compared with CMR (r = 0.91 at baseline; r = 0.90 at 12 months, respectively). CONCLUSION As compared with conventional MUGA, RT3D TTE is a feasible, accurate, and reproducible alternate imaging modality for the serial monitoring of LVEF in patients with breast cancer.

Is the Presence of Mitral Annular Calcification Associated with Poor Left Atrial Function

Introduction: Mitral annular calcification (MAC) is characterized by calcium and lipid deposition in the annular fibrosa of the mitral valve. MAC is associated with cardiovascular events but little is known of its association with left atrial (LA) function. Methods: We prospectively obtained 12‐lead electrocardiograms (ECGs) and transthoracic echocardiograms (TTE) on patients scheduled for nonemergent echocardiographic assessment at a tertiary care hospital. MAC was graded as 0 = none, 1 = mild, 2 = moderate, 3 = severe. LA linear and volume measurements (stroke volume, LA passive emptying fraction, LA active emptying fraction and LA kinetic energy) were done specifically in addition to commonly measured TTE parameters. Results: From the 124 considered for the study, 72 patients remained (aged 68±18 years; 44% male) after excluding those with poor ECG tracings and/or poor TTE images. Eighteen patients had MAC; mild MAC = 14, moderate MAC = 3, severe MAC = 1. When patients with MAC were compared to those without MAC, no significant difference was noted, except for LA linear dimension index (2.1±0.4 vs. 1.9±0.3 cm/m2; P = 0.03). For those with mild and moderate MAC, a trend was noted toward lower LA function with increasing MAC severity. In addition, significant differences were noted between those with and without interatrial conduction delay, where those with such delay had significantly impaired LA stroke volume (9.8±3 vs. 19.93±4 ml; P < 0.0001), LA active emptying fraction (18.83±8 vs. 65.71±9%; P < 0.0001) and LA total/reservoir fraction (39.54±6 vs. 75.1±6%; P < 0.0001). Conclusions: MAC is associated with increase in LA linear dimension on TTE and may be equally represented with lower overall LA function. Further study in a much larger cohort is warranted to delineate these and other potential associations of MAC.

Stress Echocardiography: Abnormal Tissue Doppler Imaging in the Absence of Cardiac Allograft Vasculopathy in Heart Transplant Recipients

Background: The most significant predictor of long‐term survival in heart transplant patients is the development of accelerated cardiac allograft vasculopathy (CAV). Several studies have demonstrated the usefulness of dobutamine stress echocardiography (DSE) for screening CAV, by detecting regional wall motion abnormalities. Tissue Doppler imaging (TDI)‐derived indices during DSE allow for the early detection of ischemic heart disease (IHD), prior to a reduction in regional or global systolic function. These indices include a reduction in annular systolic velocity (S′), a decrease in early diastolic annular velocity (E′), and prolongation of time to E′. In cardiac transplant patients, the application of these TDI abnormalities during DSE remains unknown. Objective: The objective of this study was to evaluate the pattern of (TDI‐derived indices of systolic and diastolic function during DSE in cardiac transplant patients without evidence of CAV. Methods: A retrospective evaluation of 30 patients (mean age 54 ± 11 years) who had both DSE and coronary angiography was performed. The control group consisted of 15 patients referred to rule out coronary artery disease while the study group consisted of 15 cardiac transplant patients referred for routine annual follow‐up. During each stage of DSE, tissue Doppler measurements of systolic (S′), early (E′), and late (A′) diastolic velocities of the lateral annulus were taken. Results: All 30 patients had normal DSE based on systolic regional function and normal coronary angiograms with no stenosis >50%. There was no difference in hemodynamic parameters during the DSE at baseline and with stress. Despite normal coronaries, cardiac transplant patients demonstrated lower S′, E′, and A′ velocities at peak stress compared to the control patients. Conclusion: Dobutamine‐induced augmentation of TDI velocities of the lateral annulus, normally observed in the absence of ischemia in nontransplanted adults, is reduced in cardiac transplant recipients.

Correlation of Echocardiographic Left Atrial Abnormality With Myocardial Ischemia During Myocardial Perfusion Assessment in the Presence of Known Left Ventricular Hypertrophy

Left atrial (LA) abnormality, an easily quantifiable parameter of left ventricular (LV) diastolic dysfunction, has been associated with cardiovascular risk similar to that of LV hypertrophy. The correlation between LV hypertrophy and LA abnormality among patients undergoing myocardial perfusion (MP) study has not been described. We prospectively studied 78 consecutive patients with LV hypertrophy who underwent MP study after screening for electrocardiographic and echocardiographic LA abnormality over a 6-month period. Of those, 48 had a positive MP imaging result, and 30 did not. LA size (p = 0.002) and P-wave duration (p = 0.017) were significantly increased in the former. The differential change in LA size (no defect = 35 ± 4, mild = 36 ± 5, moderate = 38 ± 5, severe = 44 ± 5 mm; p <0.0001) and P-wave duration (no defect = 107 ± 14, mild = 110 ± 17, moderate = 113 ± 15, severe = 127 ± 22 ms; p = 0.003) was greatest when the MP study defect exceeded moderate severity. In conclusion, the presence of LA abnormality could assist during MP study interpretation among patients with LV hypertrophy when such markers appear to be correlated with the severity of the MP study defect.

The utility of dobutamine stress echocardiography for the diagnosis of coronary artery disease in the HIV population.

Background: The introduction of highly active antiretroviral therapy (HAART) has increased human immunodeficiency virus (HIV) patient longevity by 10–15 years. This increased longevity has habituated new cardiovascular complications, in particular, accelerated coronary artery disease (CAD). Although dobutamine stress echocardiography (DSE) is a highly sensitive and specific test for the noninvasive detection of underlying CAD in the general population, its utility in the HIV population remains unknown. Objective: The objective of the current study was to assess the validity of DSE for the noninvasive detection of underlying symptomatic CAD in the HIV population using cardiac catheterization as the gold standard. Methods and results: A total of 40 HIV positive patients (mean 49 ± 8 years; 31 males) between 2006 and 2009 inclusively underwent routine DSE and coronary angiography. A positive stress echo with new wall motion abnormalities was detected in 9 (23%) individuals. Coronary angiography, following DSE, detected obstructive CAD in 12 (30%) individuals. For the diagnosis of obstructive CAD, DSE has a sensitivity of 67%, specificity of 97%, positive predictive value (PPV) of 89%, and negative predictive value (NPV) of 87%. Conclusion: In this select HIV population, DSE was highly specific for the noninvasive detection of obstructive CAD. (Echocardiography 2010;27:1228‐1232)

Forgotten but not extinct: lessons in hemodynamics and imaging from pancardiac rheumatic heart disease.

Simultaneous valvular, pericardial and myocardial involvement from chronic rheumatic heart disease is a rare phenomenon. We describe a novel patient with simultaneous aortic stenosis, mitral stenosis, constrictive pericarditis and pathologic myocardial rheumatic involvement. Lessons and pitfalls of the catheterization hemodynamics for concomitant multivalvular disease and constrictive physiology are outlined. Echocardiographic, computed tomographic (CT) imaging and pathologic findings are presented for the pancardiac involvement in this case.

Differences in Treadmill Exercise Tolerance Parameters Between Patients With Partial and Advanced Interatrial Depolarization Abnormality

Advanced interatrial block (aIAB) is considerably much less common than partial interatrial block (pIAB), occuring in <2% of the elderly hospitalized population. Less is, therefore, known of the true clinical burden of aIAB, particularly in relation to graded exercise. Therefore, 12 patients with aIAB and 30 patients with pIAB who performed a baseline exercise tolerance test and had a repeat test performed > or = 2 years later were included in the study. Exercise tolerance, echocardiographic findings, and major adverse cardiovascular events were compared. Left atrial size progressed at a significantly faster rate in those with aIAB. In addition, Duke Prognostic Treadmill scores were significantly lower on follow-up in those patients with aIAB. Overall, patients with aIAB had significantly greater left atrial size (48.3 +/- 9 vs 42.8 +/- 4 mm, p < 0.01) and significantly lower Duke Prognostic Treadmill scores than those with pIAB (-0.2 +/- 5 vs 4.1 +/- 4, p < 0.05). There were, however, no significant differences in the occurence of major adverse cardiovascular events. In conclusion, left atrial size progressed at a significantly faster rate but Duke Prognostic Treadmill scores were significantly lower in those with aIAB compared with patients with pIAB after > or = 2 years of follow-up. Further study is required to determine whether patients with aIAB require follow-up echocardiography and/or exercise tolerance tests for optimal risk stratification.