The Incidence and Natural Progression of New-Onset Postoperative Atrial Fibrillation.

OBJECTIVES: This study aimed to characterize the natural progression and recurrence of new-onset postoperative atrial fibrillation (POAF) during an intermediate-term follow-up post cardiac surgery by using continuous event monitoring. BACKGROUND: New-onset POAF is a common complication after cardiac surgery and is associated with an increased risk for stroke and all-cause mortality. Long-term data on new POAF recurrence and anticoagulation remain sparse. METHODS: This is a single-center, prospective observational study evaluating 42 patients undergoing cardiac surgery and diagnosed during indexed admission with new-onset, transient, POAF between May 2015 and December 2019. Before discharge, all patients received implantable loop recorders for continuous monitoring. Study outcomes were the presence and timing of atrial fibrillation (AF) recurrence (first, second, and more than 2 AF recurrences), all-cause mortality, and cerebrovascular accidents. A "per-month interval" analysis of proportion of patients with any AF recurrence was assessed and reported per period of follow-up time. Kaplan-Meier analysis was used to calculate the time to first AF recurrence and report the first AF recurrence rates. RESULTS: Forty-two patients (mean age 67.6 ± 9.6 years, 74% male, mean CHADS2-VASc 3.5 ± 1.5) were evaluated during a mean follow-up of 1.7 ± 1.2 years. AF recurrence after discharge occurred in 30 patients (71%) and of those, 59% had AF episodes equal to or longer than 5 minutes (median AF duration at 1 month was 32 minutes [interquartile range 5.5-106], whereas median AF duration beyond 1 month was 15 minutes [interquartile range 6.3-49]). Twenty-four (80%) of the 30 patients had their first AF recurrence within the first month. During months 1 to 12 follow-up, 76% of patients had any AF recurrences (10% had their first AF recurrence, 43% had their second AF recurrence, and 23% had more than 2 AF recurrences). Beyond 1 year of follow-up, 30% of patients had any AF recurrences (10% had their first AF recurrence, 7% had their second AF recurrence, and 13% had more than 2 AF recurrences). Using Kaplan-Meier analysis, the median time to first AF recurrence was 0.83 months (95% CI: 0.37 to 6) and the detection of first AF recurrence rate at 1, 3, 6, 12, 18, and 24 months was 57.1%, 59.5%, 64.3%, 64.3%, 67.3%, and 73.2%, respectively. During follow-up, there was 1 death ([-] AF recurrence) and 2 cerebrovascular accidents ([+] AF recurrence). CONCLUSIONS: In this study of continuous monitoring with implantable loop recorders, the recurrence of AF in patients who develop transient POAF is common in the first month postoperatively. Of the patients who developed postoperative AF, 76% had any recurrence in months 1 to 12, and 30% had any recurrence beyond 1-year follow-up. Current guidelines recommend anticoagulation for POAF for 30 days. The results of this study warrant further investigation into continued monitoring and longer-term anticoagulation in this population within the context of our findings that AF duration was <30 minutes beyond 1 month.

Perioperative clinical utility of myocardial deformation imaging: a narrative review.

Preoperative cardiac function is an important predictor of postoperative outcomes. Patients with heart failure are at higher risk of perioperative morbidity and mortality. Left ventricular ejection fraction, derived by standard echocardiography, is most frequently used to assess cardiac function in the intraoperative and postoperative periods. Myocardial strain analysis, a measurement of myocardial deformation, can provide additional information to left venricular eject fraction estimation. Here, we provide an overview of myocardial strain and different methods used to evaluate strain, including speckle tracking echocardiography. Speckle tracking echocardiography is an imaging modality that can analyse and track small segments of the myocardium, which provides greater detail for assessing global and regional cardiac motion and function. We further review the literature to illustrate the value of speckle tracking echocardiography-derived myocardial strain in describing cardiac function and its association with adverse surgical outcomes in the perioperative period, including low cardiac output states, need for inotropic support, postoperative arrhythmias, subclinical myocardial ischaemia, and length of hospital stay.

Echocardiographic Assessment for the Detection of Cardiotoxicity Due to Vascular Endothelial Growth Factor Inhibitor Therapy in Metastatic Renal Cell and Colorectal Cancers.

BACKGROUND: Cardio-oncology is a recently established discipline that focuses on the management of patients with cancer who are at risk for developing cardiovascular complications as a result of their underlying oncologic treatment. In metastatic colorectal cancer (mCRC) and metastatic renal cell carcinoma (mRCC), vascular endothelial growth factor inhibitor (VEGF-i) therapy is commonly used to improve overall survival. Although these novel anticancer drugs may lead to the development of cardiotoxicity, whether early detection of cardiac dysfunction using serial echocardiography could potentially prevent the development of heart failure in this patient population requires further study. The aim of this study was to investigate the role of two-dimensional speckle-tracking echocardiography in the detection of cardiotoxicity due to VEGF-i therapy in patients with mCRC or mRCC. METHODS: Patients with mRCC or mCRC were evaluated using serial echocardiography at baseline and 1, 3, and 6 months following VEGF-i treatment. RESULTS: A total of 40 patients (34 men; mean age, 63 ± 9 years) receiving VEGF-i therapy were prospectively recruited at two academic centers: 26 (65%) were receiving sunitinib, eight (20%) pazopanib, and six (15%) bevacizumab. The following observations were made: (1) 8% of patients developed clinically asymptomatic cancer therapeutics-related cardiac dysfunction; (2) 30% of patients developed clinically significant decreases in global longitudinal strain, a marker for early subclinical cardiac dysfunction; (3) baseline abnormalities in global longitudinal strain may identify a subset of patients at higher risk for developing cancer therapeutics-related cardiac dysfunction; and (4) new or worsening hypertension was the most common adverse cardiovascular event, afflicting nearly one third of the study population. CONCLUSIONS: Cardiac dysfunction defined by serial changes in myocardial strain assessed using two-dimensional speckle-tracking echocardiography occurs in patients undergoing treatment with VEGF-i for mCRC or mRCC, which may provide an opportunity for preventive interventions.

Deregulation of miR-34a and Its Chaperon Hsp70 in Hepatitis C virus-Induced Liver Cirrhosis and Hepatocellular Carcinoma Patients

Background: MicroRNA deregulation may occur during hepatocellular carcinoma (HCC) genesis and progression stages. MicroRNA-34a (miR-34a) functions as a tumor suppressor and is down-regulated or silenced in a variety of human cancers, while heat shock proteins (Hsps) play important roles in assisting protein folding and preventing both protein aggregation and transport across membranes. The present study aimed to evaluating serum expression of miR-34a and its target Hsp70 for early detection of HCC in patients with liver cirrhosis (LC), focusing on correlations with clinicopathological features. Methods: A total of 180 patients were included: 120 with HCC on top of LC (60 with either early or late HCC) and 60 patients with HCV-related LC. In addition, 60 healthy individuals were considered as controls. Real-time polymerase chain reactions were performed for expression profiling of serum miR-34a and Hsp70 and for allelic discrimination of the promotor variant (rs2763979, C/T). In addition, in silico analysis was carried out. Results: All participants were heterozygote for the promotor polymorphism. miR-34a serum levels were significantly under-expressed in LC and especially HCC patients as compared to controls. Associations with a high Child-Turcotte- Pugh (CTP) score, advanced cancer stage, and number of masses were noted. In contrast the target Hsp70 was significantly overexpressed in cancer patients but not in LC group and inversely correlated with miR-34a levels. Conclusion: Utility of circulating miRNAs as biomarkers for early detection of HCC was raised. Future large-scale studies are warranted to confirm the current findings.

Impact of Stress Testing for Coronary Artery Disease Screening in Asymptomatic Patients With Diabetes Mellitus: A Community-Based Study in Olmsted County, Minnesota.

OBJECTIVE: To evaluate the impact of screening stress testing for coronary artery disease in asymptomatic patients with diabetes in a community-based population. PATIENTS AND METHODS: This observational study included 3146 patients from Olmsted County, Minnesota, with no history of coronary artery disease or cardiac symptoms in whom diabetes was newly diagnosed from January 1, 1992, through December 31, 2008. With combined all-cause mortality and myocardial infarction as the primary outcome, weighted Cox proportional hazards regression was performed with screening stress testing within 2 years of diabetes diagnosis as the time-dependent covariate. For descriptive analysis, participants were classified by their clinical experience during the first 2 years postdiagnosis as screened (asymptomatic, underwent stress test), unscreened (asymptomatic, no stress test), or symptomatic (experienced symptoms or event). RESULTS: Among the screened and unscreened participants, 54% (1358 of 2538) were men; the mean (SD) age at diabetes diagnosis was 55 years (13.8 years), and 97% (2442 of 2520) had type 2 diabetes. In event-free survival analysis, 292 patients comprised the screened cohort and 2246 patients comprised the unscreened cohort. Death or myocardial infarction occurred in 454 patients (32 patients in the screened cohort and 422 in the unscreened cohort [5-year rate, 1.9% and 5.3%, respectively]) during median (interquartile range) follow-up of 9.1 years (5.3-12.5 years). Screening stress testing was associated with improved event-free survival (hazard ratio, 0.61; P=.004), independent of cardiac risk factors. However, while stress test results were abnormal in 47 of the 292 screened patients (16%), only 6 (2%) underwent coronary revascularization. CONCLUSION: Although screening cardiac stress testing in asymptomatic patients with diabetes in this community-based population was associated with improvement in long-term event-free survival, this result does not appear to occur by coronary revascularization alone.

Self-Expanding Transcatheter Aortic Valve Replacement Versus Surgical Valve Replacement in Patients at High Risk for Surgery: A Study of Echocardiographic Change and Risk Prediction.

BACKGROUND: The CoreValve US High-Risk Clinical Study compared clinical outcomes and serial echocardiographic findings in patients with severe aortic valve stenosis after transcatheter aortic valve replacement (TAVR) with a self-expanding bioprosthesis or surgical aortic valve replacement (SAVR). METHODS AND RESULTS: Eligible patients were randomly assigned 1:1 to TAVR with a self-expanding bioprosthesis or SAVR (N=747). Echocardiograms were obtained at baseline, discharge, 30 days, 6 months, and 1 year after the procedure and were analyzed at a central core laboratory. Compared with SAVR patients (N=357), TAVR patients (N=390) had a lower mean aortic valve gradient, larger valve area, and less patient-prosthesis mismatch (all P<0.001), but more paravalvular regurgitation at discharge, which decreased at 1 year. SAVR patients experienced significant right ventricular systolic dysfunction at discharge and 1 month with normal right ventricular function at 1 year. One-year all-cause mortality was 14.2% for TAVR and 19.1% for SAVR patients. Preimplantation aortic regurgitation ≥mild was associated with reduced mortality hazard for both the TAVR (hazard ratio 0.48, 95% confidence interval 0.27-0.85; P=0.01) and the SAVR groups (hazard ratio 0.53, 95% confidence interval 0.32-0.87; P=0.01). Aortic regurgitation ≥mild after TAVR was associated with increased risk for all-cause mortality (hazard ratio 1.95, 95% confidence interval 1.08-3.53; P=0.03). CONCLUSIONS: In patients with severe aortic stenosis at increased surgical risk, TAVR was associated with better systolic valve performance, similar left ventricular remodeling, more paravalvular regurgitation, and less right ventricular systolic dysfunction compared with SAVR. Despite an overall mortality reduction for the TAVR group, ≥mild aortic valve regurgitation after TAVR was associated with an increased mortality hazard. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01240902.

Regadenoson Stress Real-Time Myocardial Perfusion Echocardiography for Detection of Coronary Artery Disease: Feasibility and Accuracy of Two Different Ultrasound Contrast Agents.

BACKGROUND: The aim of this study was to compare the efficacy of myocardial perfusion (MP) and wall motion (WM) analysis obtained with real-time myocardial contrast echocardiography (RTMCE) and two widely used contrast agents in detecting coronary artery disease after injection of the vasodilator regadenoson. METHODS: One hundred fifty patients were studied at two academic centers using regadenoson (400-µg intravenous bolus) vasodilator stress RTMCE (7.5% Optison infusion [n = 50] or 1.5% Definity infusion [n = 100]). Both MP and WM with RTMCE were analyzed at rest and after regadenoson bolus. Comparisons of WM and MP sensitivity, specificity, and accuracy were made. Quantitative angiography was performed in all patients within 1 month of the regadenoson stress study (>50% and >70% diameter stenosis was considered significant). Reviewers were blinded to all clinical and quantitative angiographic data. RESULTS: Rate-pressure product after regadenoson was higher in Optison than Definity patients (P = .004). Using a 50% diameter stenosis on quantitative angiography as a reference standard, overall sensitivity, specificity, and accuracy for combined WM and MP analysis were not different for both agents (Optison, 77%, 64%, and 73%; Definity, 80%, 74%, and 78%; P = NS). The sensitivity, specificity, and accuracy of WM analysis alone for Optison were 68%, 71%, and 69% compared with 60%, 72%, and 66% for Definity (P = NS). Adding MP analysis improved the sensitivity and accuracy of Definity for detecting both >50% and >70% stenoses (P < .001 vs WM), while MP analysis did not improve the sensitivity of Optison for detecting either >50 or >70% stenoses. CONCLUSIONS: RTMCE during regadenoson stress using either Optison or Definity is a rapid and effective method for the detection of coronary artery disease. The ability of MP imaging to improve WM accuracy may depend on the rate-pressure product achieved.

Impact of utilizing a women-based formula for determining adequacy of the chronotropic response during exercise treadmill testing.

BACKGROUND: A women-based formula for calculation of age-predicted maximum heart rate [age-predicted maximum heart rate=206-(0.88×age)] was established in asymptomatic volunteer women undergoing treadmill exercise tolerance testing (ETT). We sought to perform a comparison of the performance of this women-based formula for prediction of peak heart rate to the traditional formula [220-age] and our own database-generated prediction formula in a large database of women undergoing ETT. METHODS: We performed a retrospective analysis of all consecutive women who underwent symptom-limited Bruce protocol ETT at the Mayo Clinic from 1994 to 2010. Women with known cardiovascular disease or those using beta blockers, calcium channel blockers, or digitalis were excluded. Separate analyses were performed according to symptomatic status. RESULTS: The study included 11,029 women (89.4% Caucasian) with a mean age 52±12 years; 3,632 (33%) were referred specifically for evaluation of symptoms. Age-predicted maximum heart rate calculated by the traditional formula was achieved by 49.7% of women versus 69.9% by the women-based formula with most of the underestimation observed in older women. Average absolute deviation between achieved and predicted peak heart rate (HR) was 10.85±9.18 bpm for traditional versus 11.98±9.00 for women-based formulas (dependent t=-16.64, p<0.0001). The linear regression line calculated from our population [HR=201-(0.67×age)] was closer to the women-based formula, both in terms of intercept and slope than the traditional formula. Peak HR was shown to be slightly affected (-2.5 bpm) by symptom status at referral, whereas smoking and diabetes more significantly reduced achieved peak HR. CONCLUSIONS: The women-based formula underestimated peak HR, especially in older women, but was observed to be closer in both intercept and slope to the regression line determined from our study in this large population of female patients. These sex-unique observations should be taken into account when determining adequacy and targets for ETT in women.

Relationship between exercise heart rate and age in men vs women.

OBJECTIVE: To analyze a large cohort of patients who underwent exercise testing and also report sex differences in other exercise heart rate (HR) parameters to determine whether separate sex-based equations to predict peak HR are indicated. PATIENTS AND METHODS: Patients aged 40 to 89 years who performed treadmill exercise tests (Bruce protocol) from September 21, 1993, to December 20, 2010, were included. Patients with cardiovascular disease or taking HR-attenuating drugs were excluded. After analyses on preliminary cohort, peak HR-modifying factors were eliminated to obtain a pure data set. Analysis of variance was used to test difference in HR responses by sex with age adjustment. RESULTS: A total of 37,010 patients (67.3% men) were included in the preliminary cohort. Men had higher peak HR (166±17 vs 163±16 beats/min [bpm]; P<.001), HR reserve (90±19 vs 84±17 bpm; P<.001), and HR recovery (19±8 vs 18±9 bpm; P<.03). Poor exercise capacity, current smoking, diabetes, and obesity had significant peak HR-lowering effects (all P<.001). In a pure cohort of 19,013 patients (51.3% of full cohort) without these factors, regression lines approximated more closely the traditional line of 220 - age. For men, the regression line in our final cohort was peak HR = 220 - 0.95 × age. For women, both slope (0.79 bpm/y) and intercept (210 bpm) were still substantially different from those obtained with the traditional formula. CONCLUSION: The HR responses to exercise are different in men and women. The HR response of men was close to that obtained with the traditional formula, but peak HR in women had a lower intercept and decreased more slowly with age. A separate formula for peak HR in women appears to be appropriate.

Relationship between HgbA1c and myocardial blood flow reserve in patients with type 2 diabetes mellitus: noninvasive assessment using real-time myocardial perfusion echocardiography.

To study the relationship between glycosylated hemoglobin (HgbA1c) and myocardial perfusion in type 2 diabetes mellitus (T2DM) patients, we prospectively enrolled 24 patients with known or suspected coronary artery disease (CAD) who underwent adenosine stress by real-time myocardial perfusion echocardiography (RTMPE). HgbA1c was measured at time of RTMPE. Microbubble velocity (ß min(-1)), myocardial blood flow (MBF, mL/min/g), and myocardial blood flow reserve (MBFR) were quantified. Quantitative MCE analysis was feasible in all patients (272/384 segments, 71%). Those with HgbA1c > 7.1% had significantly lower ßreserve and MBFR than those with HgbA1c ≤ 7.1% (P < 0.05). In patients with suspected CAD, there was a significant inverse correlation between MBFR and HgbA1c (r = -0.279, P = 0.01); however, in those with known CAD, this relationship was not significant (r = -0.117, P = 0.129). Using a MBFR cutoff value > 2 as normal, HgbA1c > 7.1% significantly increased the risk for abnormal MBFR, (adjusted odds ratio: 1.92, 95% CI: 1.12-3.35, P = 0.02). Optimal glycemic control is associated with preservation of MBFR as determined by RTMPE, in T2DM patients at risk for CAD.

Contrast echocardiography for assessment of left ventricular thrombi.

The diagnosis of intracardiac thrombi remains clinically relevant, with associated risks of systemic embolization and implications for antithrombotic management. Intravenously injected ultrasound contrast agents, composed of microbubbles smaller than red blood cells, have become established essential adjunctive tools for performance of state-of-the-art echocardiography, providing important information on cardiac structure and function. Despite advances in other imaging modalities, echocardiography remains the initial tool for diagnosis and risk stratification in patients predisposed to developing cardiac thrombi. Ultrasound contrast agents are approved for left ventricular (LV) opacification and endocardial border definition. Additionally, the use of contrast echocardiography facilitates LV thrombus detection by providing contrast opacification within the cardiac chambers to clearly show the "filling defect" of an intracardiac thrombus. Furthermore, contrast perfusion echocardiography can provide an assessment of the tissue characteristics of LV masses suspicious for intracardiac thrombi and, by differentiating an avascular thrombus from a tumor, results in improved diagnostic performance of echocardiography. This article presents a clinical vignette highlighting the sound judgment of using contrast echocardiography to aid in the diagnosis of LV thrombi and will review recent advances in imaging modalities for intracardiac thrombus detection.

Effect of stress echocardiography testing on changes in cardiovascular risk behaviors in postmenopausal women: a prospective survey study.

BACKGROUND: We evaluated the impact of contrast stress echocardiography (CSE) testing results on cardiovascular (CV) risk behaviors in postmenopausal women presenting with chest pain symptoms. This was a substudy of the Stress Echocardiography in Menopausal Women at Risk for Coronary Artery Disease (SMART) trial. METHODS: From 2004 to 2007, 366 women (mean age 54.4 ± 5.5 years, range 40-65; body mass index (BMI) 31.4 ± 6.68; Caucasian in 95%) completed CSE and were invited to participate in the Women's Heart Clinic Risk Assessment Questionnaire (WHCRAQ survey) at the time of CSE and after 2 years. Of the 366, 203 (55%) postmenopausal women completed both the baseline and 2-year follow-up surveys (age 61 ± 5 years; Framingham risk score 6 ± 4%, 81% treadmill CSE, 19% dobutamine CSE). WHCRAQ assessed medical history, hormone therapy (HT), and CV risk behaviors (cigarette smoking history, including current smoking and mean cigarettes smoked per day; physical activity or exercise, including mean exercise minutes per week; and dietary fat intake, alcohol intake, and mean alcohol drinks per week). Abnormal CSE was defined as a new or worsening stress wall motion abnormality. Post-CSE changes in CV risk behaviors were determined by comparing baseline versus 2-year data. RESULTS: Of the 203 women who completed the survey at baseline and 2-year CSE, 29 were excluded to avoid confounding effect (coronary angiography [CA] was performed during follow-up). Of 174 women (55% hypertensive, 10% diabetic, 76% hyperlipidemic, and 25% on HT), CSE was abnormal in 10%. Baseline characteristics were not significantly different in normal versus abnormal CSE, apart from diabetes (8% vs. 24%, p=0.04). Slightly more women with normal CSE were taking HT than not (27% vs. 12%, p=0.19). CV risk behaviors that were different in normal versus abnormal CSE included current smoking, alcohol drinks per week, and higher fat diet (8% vs. 24%, p=0.03; 2.5 ± 3.5 vs. 1.94±5.2, p=0.031; and 92% vs. 76%, p=0.03, respectively). Cigarette smoking decreased (mean difference of -1.5 cigarettes per day, p=0.014) in the abnormal-CSE group, whereas number of alcohol drinks per week increased (mean difference +0.38, p=0.009) in the normal-CSE group. CONCLUSION: We observed an association of lifestyle changes with CSE test results in postmenopausal women.

Detection of myocardial microvascular disease using contrast echocardiography during adenosine stress in type 2 diabetes mellitus: prospective comparison with single-photon emission computed tomography.

PURPOSE: To evaluate myocardial microvascular disease in patients with type 2 diabetes mellitus (DM) using myocardial contrast echocardiography (MCE) and to report on its diagnostic accuracy using single photon emission tomography (SPECT) as reference test. METHODS: We prospectively enrolled 79 patients (25 DM; 66 ±11 years) who underwent simultaneous SPECT and MCE with contrast agent during adenosine stress. MCE and SPECT were visually analyzed using 17 segments. Quantitative MCE parameters were derived from replenishment curves. Microbubble velocity (ß min(-1)), absolute myocardial blood flow (MBF ml/min/g), and reserve values were calculated. Diagnostic accuracy and area under curve (AUC) was reported. RESULTS: Patients with DM had higher BMI vs non DM (33±7 vs 28±5kg/m(2) P=0 .007), with more prior myocardial infarction (40 vs 15% P=.01). Visual MCE was abnormal in 40 (51%) patients (60% in DM vs 46% in non DM P=0.04). SPECT was abnormal in 38 (48%) patients [60% in DM vs 42% non DM, P=0.01]. Reserve parameters were lower in DM vs. non DM patients: (ß 1.77±1.12 vs 2.20±1.4, P<0.001 and MBF 2.86± 2.62 vs. 3.67±2.84, P<0.001). DM patients without CAD on SPECT had significantly lower ß, and MBF reserve compared to non DM patients without CAD. Compared to SPECT, ß reserve cutoff 1.6 had AUC 0.817, sensitivity 81%, and specificity 66% while MBF reserve cutoff 1.9 had AUC 0.760, sensitivity 79%, and specificity 63% in DM patients. CONCLUSION: Diabetes is associated with myocardial microvascular abnormalities as evidenced by abnormal myocardial perfusion on visual and quantitative MCE.

Assessment of myocardial perfusion during adenosine stress using real time three-dimensional and two-dimensional myocardial contrast echocardiography: comparison with single-photon emission computed tomography.

OBJECTIVES: To evaluate diagnostic accuracy of adenosine two-dimensional and three-dimensional myocardial contrast echocardiography (2D- and 3D-MCE) compared with single-photon emission computed tomography (SPECT) for assessing myocardial perfusion. METHODS: From January through August 2007, patients with known or suspected CAD who were referred for SPECT underwent simultaneous adenosine 2D-MCE and 3D-MCE (live and full volume [FV]). Perfusion and wall motion in 17 segments in the left anterior descending, left circumflex, and right coronary artery territories were analyzed. RESULTS: We studied 30 patients: mean (SD) age, 72.6 (8.2) years; 19 (63%) men. Perfusion by SPECT was abnormal in 13 patients (43%). When comparing MCE with SPECT, sensitivity was comparable for 2D-MCE, 92%; live 3D-MCE, 91%; and FV 3D-MCE, 90%. Specificity was comparable for 2D-MCE, 75%; live 3D-MCE, 69%; and FV 3D-MCE, 79%. Agreement between live 3D-MCE and 2D-MCE was 92% (kappa[SE], 0.83 [0.17]) and between FV 3D-MCE and 2D-MCE, 88% (kappa[SE], 0.76 [0.13]). For eight patients in whom SPECT showed reversible defects, live 3D-MCE correctly identified defects in seven (88%), whereas FV 3D-MCE correctly identified them in five (63%) (P = 0.57). CONCLUSION: Myocardial perfusion assessment is feasible by 3D-MCE with the advantage of rapid, facile acquisition and offline image manipulation.

Diagnostic accuracy of contrast echocardiography during adenosine stress for detection of abnormal myocardial perfusion: a prospective comparison with technetium-99 m sestamibi single-photon emission computed tomography.

Myocardial contrast echocardiography (MCE) utilizes compressible microbubbles behaving similarly to red blood cells. Destruction of microbubbles and observation of the gradual refill into the myocardium are key to evaluating perfusion using real-time MCE. We aimed to assess the feasibility and diagnostic accuracy of qualitative MCE utilizing a 17-segment model for localization of myocardial perfusion abnormalities compared with simultaneous technetium-99 m sestamibi single-photon emission computed tomography (SPECT). From July 2005 through August 2007, 97 patients with known or suspected coronary artery disease underwent simultaneous SPECT and realtime MCE during adenosine stress. Qualitative MCE and tracer uptake were analyzed visually using a 17-segment model in a blinded manner. Diagnostic accuracy and 95% confidence interval (CI) were determined. Myocardial contrast echocardiography was completed in 91 patients (age, mean [SD], 69.3 [10.9] years; body mass index, 30.0 [6.3]; 59 males [65%]). Myocardial contrast echocardiography analysis was feasible in 88 (97%) patients (261 of 264 [99%] territories; 1299 of 1497 [87%] segments). At patient level, MCE sensitivity was 88% (95% CI, 79%-94%); specificity was 85% (77%-90%). For disease detection in individual coronary territories, sensitivity and specificity were 84% (71%-92%) and 79% (72%-84%) for the left anterior descending artery; 62% (38%-80%) and 88% (83%-91%) for the left circumflex artery; and 73% (57%-82%) and 94% (89%-97%) for the right coronary artery. For MCE combined with wall-motion analysis, concordance with SPECT improved from 80% to 86%. Myocardial contrast echocardiography interobserver concordance was 81% (kappa [SE], 0.611 [0.78]). Myocardial contrast echocardiography accuracy was comparable in patients classified in accordance with presence of diabetes mellitus, myocardial infarction, hypertension, or percutaneous coronary intervention. Improved MCE specificity in detecting perfusion defects was seen in patients with no history of coronary bypass graft surgery (P = 0.005). Real-time MCE with a 17-segment model for analysis has good feasibility and accuracy in evaluation of myocardial perfusion during adenosine stress.

Pretest score for predicting microbubble contrast agent use in stress echocardiography: a method to increase efficiency in the echo laboratory.

Background. In stress echocardiography, contrast agents are used selectively to improve endocardial border definition. Early identification of candidates may facilitate use of these agents in small and medium volume laboratories where resources are limited. Methods. We studied 15232 patients who underwent stress echocardiography. Contrast agent was used if 2 or more ventricular segments were not adequately visualized without contrast. Logistic regression models were used to evaluate the association between individual characteristics and contrast use. An 11-point score was derived from the significant characteristics. Results. Variables associated with microbubble use were age, sex, smoking, presence of multiple risk factors, bodymass index (BMI), referral for dobutamine stress echocardiography, history of coronary artery disease, and abnormal baseline electrocardiogram. All variables except BMI were given a score of 1 if present and 0 if absent; BMI was given a score of 0 to 4 according to its value. An increased score was directly proportional to increased likelihood of contrast use. The score cutoff value to optimize sensitivity and specificity was 5. Conclusions. A pretest score can be computed from information available before imaging. It may facilitate contrast agent use through early identification of patients who are likely to benefit from improved endocardial border definition.

Microvascular function in Takotsubo cardiomyopathy with contrast echocardiography: prospective evaluation and review of literature.

BACKGROUND: Takotsubo cardiomyopathy (TC) mimics ST-elevation myocardial infarction without substantial angiographic stenosis. Coronary microvascular dysfunction has been proposed as a possible mechanism in TC. The aim of this study was to evaluate microvascular function in TC using real-time myocardial contrast echocardiography (MCE). METHODS: Real-time MCE was performed within 24 hours of coronary angiographic diagnosis of TC. Myocardial perfusion was evaluated through qualitative and quantitative myocardial contrast echocardiographic analyses comparing normal segments with segments with dysfunctional wall motion (WM). RESULTS: From January 2007 to January 2008, 11 patients received diagnoses of TC. Of these patients, 9 were prospectively enrolled (mean age, 70.9 +/- 17.5 years; 8 women). Qualitative and quantitative myocardial contrast echocardiographic analyses were feasible in 87% and 81% of segments. Overall, concordance between qualitative MCE and WM for normal versus abnormal analysis was observed in 71% of segments (kappa = 0.442, SE = 0.08). Significantly lower myocardial blood flow velocity (beta) and lower myocardial blood flow (Abeta) were detected in segments with dysfunctional WM compared with those with normal WM (beta = 0.55 +/- 0.39 vs 0.90 +/- 0.77, P = .009; Abeta = 5.31 +/- 3.92 vs 12.38 +/- 13.47, P = .002). In the discordant segments between qualitative MCE and WM, the quantitative perfusion parameters beta and Abeta were significantly lower in segments with dysfunctional WM compared with those with normal WM (beta = 0.22 +/- 0.20 vs 1.79 +/- 0.57, P = .01; Abeta = 1.90 +/- 1.1 vs 24.29 +/- 19.9, P = .02). Recovery of WM abnormalities was detected in all patients during follow-up echocardiography (mean, 60.3 +/- 66.0 days). No contrast-related side effects were reported. During mean follow-up of 5.9 +/- 4.6 months, there were no cardiac events, but 1 noncardiac death (from lung cancer) occurred. CONCLUSION: TC is associated with abnormal myocardial perfusion detected with qualitative and quantitative MCE, indicative of microvascular dysfunction.

Myocardial contrast echocardiography in biopsy-proven primary cardiac amyloidosis.

Cardiac vasculature is affected in 88-90% of patients with primary cardiac amyloidosis (CA). Myocardial contrast echocardiography (MCE) relies on the ultrasound detection of microbubble contrast agents that are solely confined to the intravascular space, and are therefore useful in the evaluation of flow in the microvasculature. This is the first case report describing the use of MCE during vasodilator stress to evaluate coronary flow reserve in a patient with biopsy-proven primary CA and angiographically normal coronaries. Qualitative MCE demonstrated delayed replenishment of microbubbles during peak stress; quantitative analysis was consistent with a reduction in total myocardial blood flow and reserve values. Comparative imaging modalities including strain and strain rate imaging, magnetic resonance imaging, and myocardial scintigraphy were suggestive to the diagnosis of CA. In conclusion, MCE is a method for recognition of microvascular dysfunction, and might be considered as a useful tool to augment echocardiographic assessment in the early diagnosis of CA.

Assessment of the vascularity of a left atrial mass using myocardial perfusion contrast echocardiography.

Emerging applications of myocardial contrast echocardiography (MCE) include the evaluation of myocardial perfusion, the improvement of the definition of intracavitary structures, and evaluation of the relative perfusion of a cardiac mass. We present a case of a patient that was found incidentally to have a cardiac mass on transthoracic echocardiography. MCE was used to evaluate the vascularity of the mass. This case is compared with another patient with a left atrial thrombus, which represents an "avascular" cardiac mass by MCE.

Coronary artery fistula: single-center experience spanning 17 years.

BACKGROUND: Coronary artery fistula (CAF) is an uncommon form of congenital heart disease. It is often diagnosed incidentally during angiograms. We have reported on clinical characteristics, diagnosis, and management of CAF. METHODS: Retrospective review of a tertiary referral institution's database identified 30 patients with CAF between 1987 and 2004. Mean follow-up was 31.61 +/- 48.03 months. RESULTS: Mean age was 60 +/- 12.7 years. Most common site of CAF origin was the left anterior descending artery (LAD) (14, 46.7%). The most common site of drainage was the main pulmonary artery (15, 50%). Therapeutic strategies were based on symptoms and shunt size. Conservative management was the option in 17 patients (56.7%) with small shunts and mild or no symptoms. Patients with moderate/severe symptoms and/or large shunts were treated with either percutaneous embolization (6, 20%) or surgical ligation (7, 23.3%). Four patients (13.3%) died during follow-up. No deaths were reported in the embolization group, two patients died of cancer in the conservative management group, and two patients died in the surgical group due to cardiac tamponade and cancer, respectively. CONCLUSIONS: Origin of CAF was predominantly from the left system. Clinical presentations were variable depending on type, size of fistula, and the presence of other cardiac conditions. Management of CAF is still controversial and treatment of adult asymptomatic patients with nonsignificant shunting is still a matter of debate. Newer imaging modalities may enhance noninvasive diagnosis. A national registry is necessary for further insights into optimal treatment for large fistulae and the natural history of smaller fistulae.