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Objectives This study sought to evaluate a decision algorithm for the estimation of left ventricular filling pressure (LVFP) in patients with mitral annular calcification (MAC). Background In a single center study, Abudiab et al evaluated echocardiographic parameters to estimate LVFP in patients with MAC against invasive hemodynamic measurements and developed a decision algorithm which demonstrated high predictive accuracy. Methods Retrospectively, 55 patients (mean age 68.5 ± 11.5) with MAC and a left heart catheterization within 24 hours of an echocardiogram were identified. The decision algorithm was applied using echo data to classify patients as having normal or elevated LVFP which was then compared with the invasively obtained LVFP. Results The algorithm performed poorly at predicting pre-A LVFP as normal or high (P = .182). Accuracy for the algorithm was 0.59 [0.46, 0.72] (mean [95% CI]), sensitivity was 0.45 [0.28, 0.62], specificity was 0.73 [0.54, 0.86], false positive rate was 0.27 [0.14, 0.46], and false negative rate was 0.55 [0.38, 0.72]. E/A ratio, IVRT, and E/e'ratio showed no significant relationship to actual patient LVFP. Conclusions The Abudiab et al algorithm failed to demonstrate comparable sensitivity, specificity, and accuracy in our sample. Additional study is necessary to refine this tool prior to more widespread use in clinical practice.

To date, the usage of exercise echocardiography in patients with pulmonary or congenital heart disease has been limited despite its potential for broader applications in different clinical scenarios. Exercise echocardiography can be utilized to determine the extent of pulmonary vascular damage in patients with chronic obstructive pulmonary disease by demonstrating the presence of exertional pulmonary hypertension in subjects with normal pulmonary artery pressures (PAPs) at rest. It is also useful in patients with connective tissue disease to screen for lung involvement by identifying exertional pulmonary hypertension, and in patients with established pulmonary hypertension to choose and monitor the effects of therapeutic interventions on the PAPs. Moreover, the measurement of aortic flow velocity and acceleration by exercise echocardiography may be helpful in the study of dyspnea in patients at risk for both pulmonary disease and congestive heart failure. In patients with congenital heart disease, the measurement of PAP and ventricular function both at rest and during exercise by echocardiography is the cornerstone in the investigation of the etiology of exercise intolerance in these individuals. Lastly, exercise echocardiography can also screen for residual narrowing in patients after repair of the coarctation of the aorta by detecting a significant diastolic gradient in the descending aorta during exercise provocation.

Stress echocardiography is a useful noninvasive modality for measuring dynamic outflow gradient and contractility changes in patients with hypertrophic cardiomyopathy (HCM) or dilated cardiomyopathy (DCM). In patients with HCM, stress echocardiography may determine the degree of outflow tract obstruction at rest and with activity, can detect occult systolic dysfunction in symptomatic patients with a normal resting left ventricular ejection fraction, and can also be utilized to monitor the efficacy of treatment. In individuals suffering from DCM, stress echocardiography is an important aid in the evaluation of the etiology, diagnosis, and prognosis of the disease as well as the functional status of the patient during either exercise or simulated stress conditions. Dobutamine stress echocardiography, by providing a measurement of the myocardial reserve, is a useful tool to predict the systolic recovery and clinical outcome of patients with heart failure. The stress-induced change in the wall motion score index can also be used as an accurate alternative to predict the peak oxygen consumption rate and exercise capacity of the same patient population. Finally, stress echocardiography has also been used in the identification of the predilated phase of cardiomyopathy in individuals with high clinical suspicion of the disease.

Stress echocardiography is a safe and valuable test to aid in the diagnosis and management of patients with aortic valve disorders. In patients with suspected severe aortic stenosis (AS) and low aortic gradients secondary to low cardiac output, dobutamine echocardiography distinguishes those patients with contractile reserve (CR) from those without it. By increasing the stroke volume in subjects with CR, true severe AS patients have an increase in transaortic gradients without a significant change in the valve area, whereas patients with pseudostenosis have an increase in the gradients with concomitant increase in the aortic valve area to >1 cm(2). Patients without CR are indeterminate in their AS status and have a poor prognosis. The presence of CR is also important in patients suffering from aortic insufficiency, as it may predict the development of symptoms, myocardial dysfunction, or death in the asymptomatic phase of the disease, and the potential for left ventricular functional recovery after valve replacement. Finally, both exercise and dobutamine echocardiography can help in the assessment of valve malfunction or mismatch in patients with aortic valve prostheses experiencing exercise intolerance by correlating the symptoms with the change in the aortic gradients induced during stress testing.