An Overview of Stress Echocardiography in the Study of Patients with Dilated or Hypertrophic Cardiomyopathy

Abstract

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.

The Effects of Candesartan on Left Ventricular Hypertrophy and Function in Nonobstructive Hypertrophic Cardiomyopathy

“…31 Three studies reported effects of AT1-R antagonists in patients with non obstructive HCM. 32 4,35 in the present study, increase in exercise tolerance correlated with improvement in myocardial systolic and diastolic function. Regression of LV mass appeared to be one of the major mechanisms underlying this improvement.…”

“…HCM had been diagnosed on the basis of echocardiography showing a nondilated, hypertrophied LV (any wall thickness Ͼ15 mm) in the absence of known causes of LV hypertrophy, hypertension, or valvular disease. 18,19 Exclusion criteria were as follows 1 : hypertrophic obstructive cardiomyopathy defined as presence of a resting gradient in LV outflow tract Ն30 mmHg or in right ventricular outflow tract Ն15 mm Hg at Doppler echocardiography 2 ; atrial fibrillation 3 ; treatment with ACE inhibitors or AT1-R antagonists at any time in the past 4 ; contraindications to AT1-R antagonists 5 ; coronary artery disease, renal failure, hepatic disorders or serious intercurrent illness limiting survival; and 6 poor echocardiographic image quality. The study protocol was approved by the Medical Ethics Committees of all participating institutions and informed consent was obtained from all patients.…”

“…1,2 The extent of left ventricular hypertrophy is one of the major determinants of symptoms and prognosis. 3,4 Angiotensin II has trophic effects on the heart and plays an important role in the development of myocardial hypertrophy. 5,6 Inhibition of angiotensin-converting enzyme (ACE) or the angiotensin II type 1 receptor (AT1-R) induced regression of myocardial hypertrophy in patients with hypertension or after myocardial infarction.…”

Basic Echocardiographic Features of Patients With Latent Left Ventricular Outflow Tract Obstruction Without Left Ventricular Hypertrophy

“…While one useful modality for detecting L-LVOTO is dobutamine stress echocardiography (DSE), 6) it cannot be performed easily in all hospital settings. Accordingly, there is a need for identification of the basic echocardiographic features that suggest the presence of L-LVOTO in non-LVH patients.…”

“…4,5) Although L-LVOTO in non-LVH patients has a potential to induce cardiovascular events, the prevalence, clinical course, and prognosis of L-LVOTO in non-LVH patients still remain elusive. Therefore, such patients have to be followed carefully and their clinical outcome characterized.While one useful modality for detecting L-LVOTO is dobutamine stress echocardiography (DSE), 6) it cannot be performed easily in all hospital settings. Accordingly, there is a need for identification of the basic echocardiographic features that suggest the presence of L-LVOTO in non-LVH patients.…”