Is exercise stress echocardiography useful in patients with suspected obstructive coronary artery disease who have resting left bundle branch block?

Complications of exercise and pharmacologic stress echocardiography

Stress echocardiography is a diagnostic cardiovascular exam that is commonly utilized for multiple indications, including but not limited to the assessment of obstructive coronary artery disease, valvular disease, obstructive hypertrophic cardiomyopathy, and diastolic function. Stress echocardiography can be performed via both exercise and pharmacologic modalities. Exercise stress is performed with either treadmill or bicycle-based exercise. Pharmacologic stress is performed via either dobutamine or vasodilator-mediated (i.e., dipyridamole, adenosine) stress testing. Each of these modalities is associated with a low overall prevalence of major, life-threatening adverse outcomes, though adverse events are most common with dobutamine stress echocardiography. In light of the recent COVID-19 pandemic, the risk of infectious complications to both the patient and stress personnel cannot be negated; however, when certain precautions are taken, the risk of infectious complications appears minimal. In this article, we review each of the stress echocardiographic modalities, examine major potential adverse outcomes and contraindications, assess the risks of stress testing in the setting of a global pandemic, and examine the utilization and safety of stress testing in special patient populations (i.e., language barriers, pediatric patients, pregnancy).

Exercise Stress Echocardiography for Stable Coronary Artery Disease: Succumbed to the Modern Conceptual Revolution or Still Alive and Kicking?

The modern conceptual revolution in managing patients with stable coronary artery disease (CAD), based on improvement in preventive and pharmacological therapy, advocates coronary artery revascularization only for smaller group of patients with refractory angina, poor left ventricular systolic function, or high-risk coronary anatomy. Therefore, our conventional wisdom about stress testing must be questioned within this new and revolutionary paradigm. Exercise stress echocardiography (ESE) is still a well-known technique for assessing known or suspected stable CAD, it is safe, accessible, and well-tolerated, and there is an widespread evidence base. ESE has been remarkably resilient throughout years of innovation in noninvasive cardiology. Its value is not to be determined over the short portion of diagnostic accuracy but mainly through its prognostic value evident in a wide range of patient subsets. It is coming very close to the modern profile of a leading test that should include, in addition to an essential accettable diagnostic and prognostic accuracy, qualities of low cost, no radiation exposure, and minor environmental traces. In this review, we will discuss advantages, diagnostic accuracy, prognostic value in general and special populations, cost-effectiveness, and changes in referral patterns of ESE in the modern era.

Exercise stress echocardiography: Where are we now?

Exercise stress echocardiography (ESE) is a widely used diagnostic test in cardiology departments. ESE is mainly used to study patients with coronary artery disease; however, it has increasingly been used in other clinical scenarios including valve pathology, congenital heart disease, hypertrophic and dilated cardiomyopathies, athlete evaluations, diastolic function evaluation, and pulmonary circulation study. In our laboratories, we use an established methodology in which cardiac function is evaluated while exercising on a treadmill. After completing the exercise regimen, patients remain in a standing position or lie down on the left lateral decubitus, depending on the clinical questions to be answered for further evaluation. This method increases the quality and quantity of information obtained. Here, we present the various methods of exercise stress echocardiography and our experience in many clinical arenas in detail. We also present alternatives to ESE that may be used and their advantages and disadvantages. We review recent advances in ESE and future directions for this established method in the study of cardiac patients and underline the advantage of using a diagnostic tool that is radiation-free.

Updated knowledge and practical implementations of stress echocardiography in ischemic and non-ischemic cardiac diseases: an expert consensus of the Working Group of Echocardiography of the Hellenic Society of Cardiology

Stress echocardiography (SE) is a well-established and valid technique, widely-used for the diagnostic evaluation of patients with ischemic and non-ischemic cardiac diseases. This statement of the Echocardiography Working Group of the Hellenic Society of Cardiology summarizes the consensus of the writing group regarding the applications of SE, based on the expertise of their members and on a critical review of current medical literature. The main objectives of the consensus document include a comprehensive review of SE methodology and training, focusing on the preparation, the protocols used and the analysis of the SE images and an updated, evidence-based knowledge about SE applications on ischemic and non-ischemic heart diseases, such as in cardiomyopathies, heart failure and valvular heart disease.

Is exercise stress echocardiography useful in patients with suspected obstructive coronary artery disease who have resting left bundle branch block?

BACKGROUND

Current guidelines support exercise stress echocardiography (ESE) for evaluation of suspected obstructive coronary artery disease (OCAD) in ambulant patients with left bundle branch block (LBBB). Data regarding the diagnostic utility of ESE in patients with LBBB are limited.

HYPOTHESIS

We hypothesized that the diagnostic performance of ESE for the assessment of suspected OCAD is reduced in the context of LBBB.

METHODS

We studied 191 consecutive patients with resting LBBB undergoing ESE for the investigation of suspected OCAD between 2008 and 2015 at our center. The studies were categorized as inconclusive, normal, or abnormal. Patients with an abnormal response were subcategorized as regional ischemic response or globally abnormal.

RESULTS

Eighty-two patients (43%) demonstrated a normal left ventricular contractile response (LVCR) to exercise; 92 (48%) developed an abnormal LVCR to exercise, including 70 patients with globally abnormal and 22 patients with regional ischemic responses. Of the patients with abnormal responses, 62 patients had anatomic imaging, only 29 of whom had significant OCAD, conferring an overall specificity of ESE for significant OCAD of 21% and accuracy of 52%. Of patients who developed a regionally abnormal response, 89% had significant OCAD.

CONCLUSIONS

For patients with LBBB who develop a globally abnormal LVCR during ESE, the specificity of ESE for reliably excluding significant OCAD is significantly reduced. ESE appears to be a suboptimal test for the evaluation of OCAD in patients with resting LBBB, as about 50% of patients will have an abnormal response, the majority due to globally abnormal contraction where OCAD cannot be reliably diagnosed. Alternative testing should be considered for the investigation of suspected OCAD in patients with resting LBBB.