Myocardial stress imaging: a clinical tool has come of age

Coronary artery disease is a major cause of morbidity and mortality in the western world (1 ). Depending on the progression and severity of coronary artery disease and the myocardial response this may result in angina pectoris, myocardial infarction, chronic ischemic heart disease and cardiac death. Several techniques have been developed to evaluate patients with known or suspected coronary artery disease. In 1973, Strauss and Zaret and coworkers (2,3) hypothesized that exercise should be used to maximize differences in relative perfusion bet\veen normal and abnormal coronary vascular beds during myocardial perfusion imaging. This is a safe and simple noninvasive way of assessing myocardial perfusion at rest and to detect myocardial ischemia. In 1979, Wann and colleagues (4) demonstrated that the mechanical consequences of ischemia can be detected noninvasively by real-time two-dimensional stress echocardiography. Since then, advances in exercise and pharmacological stress protocols, developments in nuclear cardiology, and significant improvements in echocardiographic equipment have provided the foundation for the growth of myocardial stress imaging (5-11 ). Myocardial stress imaging has seen little to parallel its rapid development. Currently, noninvasive imaging of the heart using radionuclide tracers under stress and resting conditions and dobutamine stress echocardiography are established techniques for the evaluation of patients with known or suspected coronary artery disease. Myocardial stress imaging can b

Contrast-enhanced ultrasound: clinical applications in patients with atherosclerosis

Contrast-enhanced ultrasound (CEUS) is increasingly being used to evaluate patients with known or suspected atherosclerosis. The administration of a microbubble contrast agent in conjunction with ultrasound results in an improved image quality and provides information that cannot be assessed with standard B-mode ultrasound. CEUS is a high-resolution, noninvasive imaging modality, which is safe and may benefit patients with coronary, carotid, or aortic atherosclerosis. CEUS allows a reliable assessment of endocardial borders, left ventricular function, intracardiac thrombus and myocardial perfusion. CEUS results in an improved detection of carotid atherosclerosis, and allows assessment of high-risk plaque characteristics including intraplaque vascularization, and ulceration. CEUS provides real-time bedside information in patients with a suspected or known abdominal aortic aneurysm or aortic dissection. The absence of ionizing radiation and safety of the contrast agent allow repetitive imaging which is particularly useful in the follow-up of patients after endovascular aneurysm repair. New developments in CEUS-based molecular imaging will improve the understanding of the pathophysiology of atherosclerosis and may in the future allow to image and directly treat cardiovascular diseases (theragnostic CEUS). Familiarity with the strengths and limitations of CEUS may have a major impact on the management of patients with atherosclerosis

Prediction of 8-year cardiovascular outcomes in patients with systemic arterial hypertension: Value of stress Tc-99m-tetrofosmin myocardial perfusion imaging in a high-risk cohort

Systemic arterial hypertension is a strong and prevalent cardiovascular risk factor. Currently, information on the very long-term prognostic value of single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients with systemic arterial hypertension is lacking. The aim of this study was to assess the value of stress Tc-99m-tetrofosmin MPI for the prediction of very long-term outcome in these patients. The study population consisted of 608 patients with systemic arterial hypertension who underwent exercise or dobutamine stress Tc-99m-tetrofosmin MPI for the assessment of known or suspected coronary artery disease. Follow-up was successful in 600 (99%) patients. The endpoints were all-cause mortality, cardiac death, nonfatal infarction, and coronary revascularization. Kaplan-Meier survival cures were constructed and univariate and multivariate analyses were performed to identify predictors of v The mean age of the patients was 59 +/- A 10 years, and 65% of them were male. MPI findings were normal in 301 patients (50%). Myocardial perfusion abnormalities were fixed in 162 (27%) and reversible in 137 (23%) patients. During a median 8.1-year follow-up, 241 (40%) patients died (121 cardiac deaths), 52 (9%) had a nonfatal myocardial infarction, and 128 (21%) underwent coronary revascularization. Survival curves in patients with a low vs a high summed difference score diverged up to 5 years Stress Tc-99m-tetrofosmin MPI provides incremental prognostic information for the prediction of cardiovascular outcome in patients with systemic arterial hypertension. Patients with normal stress MPI have a significantly better prognosis as compared with those with an abnormal study, up to 5 years after the test is performed

Left-ventricular outflow tract acceleration time is associated with symptoms in patients with obstructive hypertrophic cardiomyopathy

AIMS: Not all obstructive hypertrophic cardiomyopathy (HCM) patients are symptomatic. The relation between obstructive HCM and symptoms is not well understood. The hypothesis of this study is that left-ventricular outflow tract (LVOT) acceleration time (AT) is associated with symptoms. METHODS: We included 187 patients (61% men, mean age 55 ± 14 years) with obstructive HCM, defined as a maximal wall thickness ≥ 15 mm and a resting or provoked LVOT peak gradient ≥ 30 mmHg. Peak velocity (PV), left-ventricular (LV) ejection time (ET), and AT (the time between LVOT flow onset and the moment of PV) were measured on continuous-wave (CW) Doppler tracings. Logistic and Cox proportional hazard regression analyses were used to evaluate the relation between symptoms [New York Heart Association (NYHA) class ≥ II] and echocardiographic measurements, including AT. Reproducibility was assessed using the intraclass correlation coefficient (ICC). RESULTS: Symptomatic patients were more often female and had higher mean AT values. Logistic regression demonstrated a significant association between AT and symptomatic status (odds ratio 1.31 per 10 ms, p < 0.01) after adjustment for sex, negative inotropes, PV, LVOT diameter, and diastolic dysfunction. AT was independently associated with symptoms and septal reduction during follow-up (hazard ratio 1.09 per 10 ms, p < 0.05). The ICC was 0.98 with a mean difference of 0.28 ± 8.4 ms. CONCLUSION: In obstructive HCM patients, increased AT is significantly related to symptoms after adjustment for sex, negative inotropes, PV, LVOT diameter, and diastolic dysfunction, and is associated with the symptomatic status during follow-up. AT represents an easily measured echocardiographic variable with excellent inter-reader reproducibility. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s40477-020-00513-3) contains supplementary material, which is available to authorized users

Impact of Early Coronary Revascularization on Long-Term Outcomes in Patients With Myocardial Ischemia on Dobutamine Stress Echocardiography

The role of early coronary revascularization in the management of stable coronary artery disease remains controversial. The aim of this study was to evaluate the impact of early coronary revascularization on long-term outcomes (>10 years) after an ischemic dobutamine stress echocardiography (DSE) in patients with known or suspected coronary artery disease. Patients without stress-induced ischemia on DSE and those who underwent late coronary revascularization (>90 days after DSE) were excluded. The final study cohort consisted of 905 patients. A DSE with a peak wall motion score index of 1.1 to 1.7 was considered mild

Long-term (>10 years) prognostic value of dobutamine stress echocardiography in a high-risk cohort

The prognostic value of dobutamine stress echocardiography (DSE) at >10-year follow-up is unknown. The aim of this study was to assess the very long-term prognostic value of DSE in a high-risk cohort of patients with known or suspected coronary artery disease. This prospective, single-center study included 3,381 patients who underwent DSE from January 1990 to January 2003. Two-dimensional echocardiographic images were acquired at rest, during dobutamine stress, and during recovery. Follow-up events were collected and included overall mortality, cardiac death, nonfatal myocardial infarction, and revascularization. The incremental value of DSE in the prediction of selected end points was evaluated using multivariate Cox proportional hazard analysis. During a mean follow-up of 13 ± 3.2 years (range 7.3 to 20.5 years), there were 1,725 deaths (51%), of which 1,128 (33%) were attributed to cardiac causes. Patients with an abnormal DSE had a higher mortality rate (44% vs 35% at 15-year follow-up, p <0.001) than those with a normal DSE. When comparing echocardiographic variables at rest to variables at maximum dose dobutamine, the chi-square of the test improved from 842 to 870 (p <0.0001) and from 684 to 740 (p <0.0001) for all-cause mortality and cardiac death, respectively. DSE provided incremental value in predicting all-cause mortality, cardiac death, and hard cardiac events. There seems, however, to be a "warranty period" of approximately 7 years, when the survival curves of a normal and abnormal DSE no longer diverge