Abdou Elhendy

Tissue Doppler and Strain Rate Imaging Detect Improvement of Myocardial Function in Iron Deficient Patients with Congestive Heart Failure after Iron Replacement Therapy

Background: Iron deficiency may contribute to diminished exercise tolerance in patients with congestive heart failure (CHF) even in absence of anemia. The aim of this study was to evaluate the effect of correction of iron deficiency on functional capacity and myocardial function in patients with CHF. Methods: We studied 40 patients with ejection fraction <40%, hemoglobin% >12 g/dL, serum ferritin <100 ug/L, and transferrin saturation <20%. Patients received 200 mg weekly doses of iron dextran complex until serum ferritin level was between 200 and 300 ug/L or transferrin saturation level was between 30% and 40%. Transthoracic echocardiogram, tissue Doppler imaging, peak systolic strain rate, and 6 minute walk test were performed before iron therapy and at 12‐week follow up. Peak early diastolic myocardial tissue velocity (E’), peak late diastolic myocardial tissue velocity (A’), and peak systolic myocardial tissue velocity (S’) were measured. Results: There was a significant improvement of New York Heart Association functional class (3.0 ± 0.4 vs. 2.1 ± 0.3, P < 0.05) and 6minutes walk distance (322 ± 104 vs. 377 ± 76, P < 0.01) from rest to follow up, respectively. Ejection fraction did not change significantly (32 ± 8% vs. 34 ± 9%, respectively). There was a significant improvement of S’‐wave (3.0 ± 0.8 cm/sec vs. 6.0 ± 1.2 cm/sec, P < 0.05), E/E’ ratio (22 ± 3 vs. 13 ± 3, P < 0.05), and peak systolic strain rate (−0.72 ± 0.11/s vs. −1.09 ± 0.37/s, P < 0.05) from baseline to follow‐up, respectively. Conclusion: Correction of iron deficiency improves functional class and walking distance in nonanemic iron deficient patients with systolic heart failure. Tissue Doppler and strain rate demonstrated a significant improvement of diastolic and systolic function after therapy despite lack of improvement of ejection fraction. (Echocardiography 2012;29:13‐18)

Clinical and biochemical predictors of increased carotid intima-media thickness in overweight and obese adolescents with type 2 diabetes.

Objective: To identify the clinical parameters associated with increased carotid intima-media thickness (CIMT) in overweight and obese adolescents with type 2 diabetes. Methods: We studied 27 patients (11 males) with type 2 diabetes. Criteria for selection were age (12–19 years), body mass index above the 95th percentile for age and gender, a positive family history of diabetes, normal or high C-peptide, and negative studies for islet cell antibodies. Age- and gender-matched healthy subjects were selected as the control group. Measurements of CIMT, lipid profile, hypersensitive C-reactive protein, hemoglobin A1C (HbA1C), and insulin resistance by homeostasis model of assessment (HOMA) were obtained for all participants. Results: CIMT was higher in diabetic patients than in healthy subjects (0.68 ± 0.16 vs. 0.58 ± 0.1, p < 0.01). The range of HbA1C in the 15 patients with uncontrolled diabetes was 7.6–10.4 (mean: 8.9 ± 0.9). CIMT, HbA1C, systolic blood pressure, triglycerides, HOMA, and C-reactive protein were significantly higher in patients with uncontrolled than with controlled diabetes. In diabetic patients, CIMT correlated positively with body mass index (p < 0.001), duration of diabetes (p < 0.001), systolic (p < 0.001) and diastolic blood pressure (p < 0.01), HbA1C (p < 0.001), HOMA (p < 0.01), and C-reactive protein (p < 0.01). Conclusions: CIMT is increased in adolescents with type 2 diabetes. Poor glycemic control, HOMA, increased C-reactive protein, body mass index, duration of diabetes, and elevated blood pressure are associated with early atherosclerosis in these patients.

Prognostic significance of QRS duration in patients with suspected coronary artery disease referred for noninvasive evaluation of myocardial ischemia.

The purpose of this study was to evaluate the prognostic significance of QRS duration in patients with suspected coronary artery disease (CAD) referred for noninvasive evaluation of myocardial ischemia by dobutamine stress echocardiography. QRS duration is a prognostic marker in patients with previous myocardial infarction and/or heart failure. The relation between QRS duration and outcome of patients without known heart disease has not been evaluated. A total of 1,227 patients (707 men, mean age 61 +/- 14 years) with suspected CAD underwent dobutamine stress echocardiography for evaluation of myocardial ischemia. Patients were followed to determine predictors of cardiac events and to assess the incremental significance of QRS duration compared to clinical and dobutamine stress echocardiographic data. During a mean follow-up of 4.2 +/- 2.4 years, 280 patients (23%) died (129 cardiac deaths), and 60 (5%) had a nonfatal infarction. Annualized cardiac death rates were 2.0% in patients with QRS duration <120 ms and 4.4% in patients with QRS duration >or=120 ms, respectively (p <0.0001). Annualized event rates for cardiac death/nonfatal infarction were 2.8% in patients with QRS duration <120 ms and 4.8% in patients with QRS duration >or=120 ms (p = 0.0001). Multivariate models identified age, male gender, smoking, QRS duration >or=120 ms, and an abnormal dobutamine stress echocardiogram as independent predictors of cardiac death and the combined end point cardiac death/nonfatal infarction. In conclusion, QRS duration is an independent predictor of cardiac death and cardiac death/nonfatal infarction in patients with suspected CAD. This risk is persistent after adjustment for clinical variables, left ventricular function, and myocardial ischemia.

Prognostic value of left atrial volume in patients who underwent dobutamine stress echocardiography for known or suspected coronary artery disease

BACKGROUND Left atrial volume indexed (LAVI) has been reported as a predictor of cardiovascular events. We sought to determine the prognostic value of LAVI for predicting the outcome of patients who underwent dobutamine stress echocardiography (DSE) for known or suspected coronary artery disease (CAD). METHODS From January 2000 to July 2005, we studied 981 patients who underwent DSE and off-line measurements of LAVI. The value of DSE over clinical and LAVI data was examined using a stepwise log-rank test. RESULTS During a median follow-up of 24 months, 56 (6%) events occurred. By univariate analysis, predictors of events were male sex, diabetes mellitus, previous myocardial infarction, left ventricular ejection fraction (LVEF), left atrial diameter indexed, LAVI, and abnormal DSE. By multivariate analysis, independent predictors were LVEF (relative risk [RR] = 0.98, 95% CI 0.95-1.00), LAVI (RR = 1.04, 95% CI 1.02-1.05), and abnormal DSE (RR = 2.70, 95% CI 1.28-5.69). In an incremental multivariate model, LAVI was additional to clinical data for predicting events (chi(2) 36.8, P < .001). The addition of DSE to clinical and LAVI yielded incremental information (chi(2) 55.3, P < .001). The 3-year event-free survival in patients with normal DSE and LAVI < or =33 mL/m(2) was 96%; with abnormal DSE and LAVI < or =33 mL/m(2), 91%; with normal DSE and LAVI >34 mL/m(2), 83%; and with abnormal DSE and LAVI >34 mL/m(2), 51%. CONCLUSION Left atrial volume indexed provides independent prognostic information in patients who underwent DSE for known or suspected CAD. Among patients with normal DSE, those with larger LAVI had worse outcome, and among patients with abnormal DSE, LAVI was still predictive.

Long-Term Prognostic Value of Dobutamine Stress Echocardiography in Diabetic Patients With Limited Exercise Capability: A 13-year follow-up study

OBJECTIVE To determine the incremental prognostic value of dobutamine stress echocardiography (DSE) at 13-year follow-up (SD 3.2 years) for predicting mortality and cardiac events in diabetic patients. RESEARCH DESIGN AND METHODS A total of 396 diabetic patients (mean age 61 ± 11 years; 252 men [64%]) with limited exercise capacity who underwent DSE for evaluation of ischemia were studied. End points were all causes of mortality, cardiac death, and hard cardiac events (cardiac death and nonfatal myocardial infarction). RESULTS During a mean follow-up of 13 years, 230 patients (58%) died (121 cardiac deaths), and 30 patients had nonfatal myocardial infarction. Cumulative survival in patients with an abnormal DSE at 5, 10, and 15 years was 68, 49, and 41%, respectively. In patients with a normal DSE, these respective numbers were 74, 57, and 44%. Multivariate analyses showed that DSE provided incremental value over clinical characteristics and stress test parameters for prediction of mortality and cardiac events. Survival analysis showed that DSE provided optimal risk stratification up to 7 years after initial testing; after that period, the risk of adverse outcome increased comparably in both normal and abnormal DSE patients. CONCLUSIONS DSE provided restricted predictive value of adverse outcome in patients with diabetes who were unable to perform an adequate exercise stress test. DSE provided optimal risk stratification up to 7 years after initial testing. Repeated DSE at that time might add to its prognostic value.

Prognostic significance of myocardial ischemia by dobutamine stress echocardiography in patients without angina pectoris after coronary revascularization.

The clinical utility of stress testing in patients without angina pectoris after revascularization has been questioned. Dobutamine stress echocardiography (DSE) is an established technique for detection of myocardial ischemia and cardiac risk stratification. We studied the prognostic value of DSE in 393 patients without typical angina pectoris after coronary revascularization. Ischemia was incremental to clinical data in predicting all-cause death (hazard ratio 3.5, 95% confidence interval 1.8 to 6.7) and cardiac death (hazard ratio 4.2, 95% confidence interval 1.8 to 9.8). In conclusion, myocardial ischemia during DSE is independently associated with an increased risk of all-cause mortality and cardiac death in these patients after adjustment for clinical data.

Comparison of Contrast Enhanced Magnetic Resonance Angiography with Invasive Cardiac Catheterization for Evaluation of Children with Pulmonary Atresia

Complete assessment of the source of pulmonary blood supply and delineation of the anatomy of pulmonary arteries are essential for the management and prognostic evaluation of pulmonary atresia (PA) patients. Invasive cardiac catheterization is considered the gold standard imaging modality to achieve this. We investigated the role of contrast enhanced magnetic resonance angiography (MRA) to evaluate the pulmonary blood supply and the anatomy of the pulmonary arteries and compared this with cardiac catheterization in children with PA. We studied 20 children with PA. Median age was 2.5 years (range 6 months–13 years). All patients were examined with cardiac catheterization and contrast enhanced MRA, and the results of both modalities were compared. There was a complete agreement between both modalities in the detection of the main pulmonary artery morphology and determination of the confluence state of the central pulmonary arteries. There was an 88% agreement for patency of the ductus arteriosus and 66% for patency of the surgically placed shunt. There was a complete agreement between both techniques on determining the presence of collaterals more than 2.5 mm. Twenty-eight collaterals of less than 2.5 mm were detected only by contrast enhanced MRA. There was a strong correlation between both modalities in measuring the pulmonary arteries and collaterals diameter (P<0.001). Contrast enhanced MRA is a safe and accurate non-invasive technique to evaluate the pulmonary artery morphology and the sources of pulmonary blood supply in children with PA.

Prognostic significance of ischemia location on stress myocardial perfusion SPECT: Tracing the fingerprints of the widow maker

One of the great advantages of myocardial perfusion SPECT imaging is its ability to localize and quantify ischemia with good correlation with invasive angiographic findings. Although the extent of perfusion abnormalities has been consistently associated with death and cardiac events, little is known about whether ischemia in a certain coronary arterial territory is particularly more predictive of adverse events. In this issue of the journal, Nudi et al demonstrated that ischemia in the distribution of the left anterior coronary artery (LAD) was independently predictive of mortality and hard cardiac events. This risk was incremental to clinical data, stress test parameters, and the number of ischemic segments. The study was conducted in patients with moderate to severe ischemia. The study supports previous findings in patients undergoing exercise stress echocardiography. The previous study was conducted in unselected patients and included those with normal test as well as mild ischemia. Both resting and inducible wall motion abnormalities were correlated with prognosis. The association of LAD-related ischemia with more adverse outcome may not be surprising considering the known larger myocardial territory served by LAD compared to the right and left circumflex coronary arteries. However, the most interesting finding is that this association persisted after adjustment for the total number of ischemic segments, suggesting that other clinical, angiographic, and imaging characteristics come into play. The bases for such an independent association with prognosis may not be entirely understood. Many hypotheses could be suggested to explain this association.

The power of stress echocardiography and myocardial perfusion scintigraphy in predicting long-term outcome. Nothing lasts forever

Cardiac stress imaging with either echocardiography or myocardial perfusion scintigraphy is a wellestablished method for evaluation of coronary artery disease and predicting outcome. In the current issue of the journal, Boiten et al reported the longest-term follow-up after stress imaging in 301 patients who underwent dobutamine stress test with simultaneous echocardiography and sestamibi myocardial perfusion SPECT imaging (MPI). Patients were followed for an average of 14 years. An abnormal test was strongly predictive of adverse outcome. Both stress echocardiography and MPI were comparable in predicting mortality and hard cardiac events. Although the number of patients was relatively small particularly during the later phase of the follow-up, the study has shown clearly a sustained prognostic value of both techniques with separation of survival curves in those with normal versus abnormal study for at least 10-12 years after the test. Based on these results, some important questions arise. Do we know everything after the stress test? Is there a need to repeat the stress test or do a different kind of imaging? The answer is probably yes in some patients, but who are these and why? What kind of subsequent imaging modality should we consider? ORDERING ANOTHER TEST AFTER A NORMAL STUDY