There are conflicting data on the incidence of ischemia by stress echocardiography in patients referred for dyspnea without accompanying chest pain.
A total of 311 consecutive patients with ...exertional dyspnea (without chest pain) referred to the echocardiography lab for ischemia evaluation from August 2008 to March 2012 were evaluated. Exercise by Bruce protocol or dobutamine stress echocardiography was performed. Resting left ventricular ejection fraction and segmental wall motion abnormalities were assessed. Multivariate logistic regression analysis was used to identify independent predictors of ischemia on stress echocardiography.
The mean age was 61 years (range, 20-96 years), with 196 women (63%). Exercise stress was performed in 114 patients (37%); the rest of the patients underwent dobutamine stress. The patient population had a high burden of obesity, diastolic dysfunction, and pulmonary hypertension. Thirty patients (10%) had evidence of stress-induced ischemia (nine 8% with exercise and 21 11% with dobutamine). In multivariate analysis, male gender (odds ratio, 2.8; P = .03), history of coronary artery disease (odds ratio, 3.5; P = .02), and resting wall motion abnormalities (odds ratio, 16.6; P < .01) were independent predictors of inducible ischemia.
The incidence of stress-induced ischemia is low in patients referred for stress echocardiography with exertional dyspnea (without chest pain). Ischemia is more likely to be present in men with histories of coronary artery disease and resting wall motion abnormalities.
Antihypertensive Therapy in Hypertrophic Cardiomyopathy Argulian, Edgar, MD, MPH; Messerli, Franz H., MD; Aziz, Emad F., DO, MB, CHB ...
The American journal of cardiology,
04/2013, Letnik:
111, Številka:
7
Journal Article
Recenzirano
Patients with coexisting hypertrophic cardiomyopathy (HC) and hypertension present diagnostic and therapeutic dilemmas. A retrospective cohort study of patients with HC with coexisting hypertension ...referred to a specialized HC program was conducted. HC and hypertension were confirmed by strict criteria. Echocardiographic data were reviewed for peak instantaneous left ventricular outflow tract gradients, at rest and with provocation. Symptom control, left ventricular outflow tract gradients, and hypertension control were compared between the first and last visits. One hundred fifteen patients (94 obstructed and 21 nonobstructed) met the eligibility criteria for the study and were included in the analysis, with the mean follow-up duration of 36 months. Because of the treatment strategy, there was a significant decrease in the number of patients treated with direct vasodilators and an increase in the use of β blockers and disopyramide. Twenty-one obstructed patients (22%) required septal reduction therapy. Overall, in obstructed patients, peak instantaneous left ventricular outflow tract gradient at rest decreased from 48 to 14 mm Hg (p <0.01), which was accompanied by significant improvement in functional class (2.4 vs 1.8, p <0.01). The prevalence of uncontrolled hypertension decreased from 56% at the initial visit to 37% at the last visit (p = 0.01). The cohort had a low rate of adverse cardiovascular outcomes such as death, acute coronary syndromes, and stroke. In conclusion, the present study demonstrates that stepwise, symptom-oriented therapy is feasible and effective in patients with coexisting HC and hypertension.
The workup of moderate-to-large pericardial effusion should focus on its hemodynamic impact and potential cause. A structured approach to diagnostic evaluation of pericardial effusion is needed. We ...retrospectively studied a contemporary cohort of 103 patients with moderate-to-large pericardial effusion hospitalized at St. Luke's Roosevelt Hospital Center from July 2009 till August 2013. Diagnosis of pericardial effusion was independently ascertained by chart review. We applied a stepwise parsimonious approach to establish the cause of pericardial effusion. In the studied cohort, the mean age was 61 years, 50% were men, and 65 patients (63%) underwent pericardial effusion drainage. Using the structured approach, the cause of the effusion was ascertained in 70 patients (68%) by noninvasive targeted testing. Malignant effusion was confirmed in 19 patients (19%). All patients with malignant effusion had either history of malignancy or suggestive noninvasive findings. In conclusion, a structured approach can help to ascertain the diagnosis in patients with moderate-to-large pericardial effusion and guide the need for pericardial drainage or sampling.
Recent studies have reported that competitive endogenous RNAs (ceRNAs) can act as sponges for a microRNA (miRNA) through their binding sites and that changes in ceRNA abundances from individual genes ...can modulate the activity of miRNAs. Consideration of this hypothesis would benefit from knowing the quantitative relationship between a miRNA and its endogenous target sites. Here, we altered intracellular target site abundance through expression of an miR-122 target in hepatocytes and livers and analyzed the effects on miR-122 target genes. Target repression was released in a threshold-like manner at high target site abundance (≥1.5 × 105 added target sites per cell), and this threshold was insensitive to the effective levels of the miRNA. Furthermore, in response to extreme metabolic liver disease models, global target site abundance of hepatocytes did not change sufficiently to affect miRNA-mediated repression. Thus, modulation of miRNA target abundance is unlikely to cause significant effects on gene expression and metabolism through a ceRNA effect.
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•Target repression is released only after adding many competing target sites•The number of added sites required for derepression is independent of miRNA levels•The apparent abundance of intracellular target sites exceeds that of the miRNAs•Changes in ceRNAs are typically too small to influence miRNA-mediated repression
Denzler et al. investigate the stoichiometric relationship of a microRNA and its target sites in primary cells. They find that microRNA target sites exceed microRNA copy numbers and that changes in the number of target sites that occur across physiological and disease conditions are typically too small to detectibly influence microRNA activity.
Ventricular-arterial stiffening is a part of the aging process that is amplified by various comorbidities. It affects normal cardiovascular reserve and limits exercise capacity. The aim of this study ...was to explore the association of physiologic determinants of ventricular-arterial interaction with exercise capacity in patients referred for exercise echocardiography with exertional dyspnea.
A total of 93 patients with exertional dyspnea without chest pain were evaluated using the Bruce protocol. Patients with left ventricular ejection fractions < 50% and those with exercise-induced myocardial ischemia were excluded. Poor exercise tolerance was defined as inability to achieve 8 metabolic equivalents.
Thirty-seven patients (40%) had poor exercise tolerance. These patients were older (mean age, 60 vs 54 years, P = .01), more likely to carry the diagnosis of hypertension (84% vs 41%, P < .01), and more likely to be treated with antihypertensive medications. In multivariate logistic regression analysis, left atrial volume index (P = .04) and arterial elastance (P < .01) were significant predictor of poor exercise capacity, while left ventricular ejection fraction, tissue Doppler indices, and global longitudinal strain were not significant.
Effective arterial elastance determined noninvasively before stress echocardiography appears to be an independent predictor of exercise tolerance in patients with exertional dyspnea.
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