Citations

Myocardial microvascular permeability and coronary sinus concentration of muscle metabolites have been shown to increase after myocardial ischemia due to epicardial coronary artery occlusion and reperfusion. However, their association with coronary microembolization is not well defined. This study tested the hypothesis that acute coronary microembolization increases microvascular permeability in the porcine heart. The left anterior descending perfusion territories of 34 anesthetized pigs (32 ± 3 kg) were embolized with equal volumes of microspheres of one of three diameters (10, 30, or 100 μm) and at three different doses for each size. Electron beam computed tomography (EBCT) was used to assess in vivo, microvascular extraction of a nonionic contrast agent (an index of microvascular permeability) before and after microembolization with microspheres at baseline and during adenosine infusion. A high-resolution three-dimensional microcomputed tomography (micro-CT) scanner was subsequently used to obtain ex vivo, the volume and corresponding surface area of the embolized myocardial islands within the perfusion territories of the microembolized coronary artery. EBCT-derived microvascular extraction of contrast agent increased within minutes after coronary microembolization ( P < 0.001 vs. baseline and vs. control values). The increase in coronary microvascular permeability was highly correlated to the micro-CT-derived total surface area of the nonperfused myocardium ( r = 0.83, P < 0.001). In conclusion, myocardial extravascular accumulation of contrast agent is markedly increased after coronary microembolization and its magnitude is in proportion to the surface area of the interface between the nonperfused and perfused territories.

Background— Previous studies have demonstrated that mitral annulus early diastolic (e′) velocity is increased in constrictive pericarditis (CP) and reduced in restrictive cardiomyopathy. However, those studies did not comprehensively evaluate mitral and tricuspid annular velocities before and after pericardiectomy. Methods and Results— We performed comprehensive echocardiography before and after pericardiectomy in 99 patients with CP, 52 with primary (idiopathic or postpericarditis etiology) and 47 with secondary CP (due to surgery or radiation). Overall, mean±SD mitral medial, mitral lateral, and tricuspid lateral e′ velocities were 12.2±4.2, 10.0±5.4, and 11.6±3.5 cm/s, respectively; annular late diastolic velocities were 10.3±4.3, 12.2±4.9, and 11.7±5.4 cm/s, respectively; and annular systolic (s′) velocities were 7.8±2.8, 8.2±2.1, and 11.2±3.8 cm/s, respectively. Medial e′ was equal to or greater than mitral lateral e′ in 74% of analyzable cases. With the exception of tricuspid s′, there were significant differences in all s′ and e′velocities between primary and secondary CP before pericardiectomy. After pericardiectomy, all annular velocities decreased significantly ( P <0.02 for all comparisons). The reduction in medial e′ velocity was greater than that of mitral lateral e′ velocity ( P <0.0001 and P =0.0004, respectively), and the mitral lateral/medial e′ ratio normalized ( P =0.0002). Conclusions— The mitral lateral/medial e′ ratio is reversed in three fourths of patients with CP. All annular velocities are lower in secondary compared to primary CP before pericardiectomy. After pericardiectomy, there is reduction of all annular velocities and normalization of the mitral lateral/medial e′ ratio.

Thyroid nodules are very common, and although the majority are benign, approximately 5% may harbor malignancy. The evaluation of the patient with solitary thyroid nodule is generally straightforward and will typically include measurement of serum TSH to assess thyroid function and fine-needle aspiration biopsy of the nodule, with or without ultrasound (US) guidance. The approach to the patient with nontoxic multinodular goiter represents a more difficult problem for the clinician. All patients should have serum TSH measured to assess functional thyroid status and US examination to evaluate the number, size, and sonographic features of the nodules and assist in the selection of nodules that may need fine-needle aspiration biopsy. Patients with nodules yielding malignant cytology should be referred for surgery. Given the lack of reliable markers to predict biological behavior of nodules with suspicious (indeterminate) cytology, patients with such nodules are generally advised to have surgery, unless autonomous function of these nodules can be confirmed by scintigraphy. Most of these patients, however, will ultimately prove to have benign follicular tumors. Many patients with benign but large goiters may experience clinical symptoms of pressure, such as dysphagia, choking sensation, or airway obstruction. Such patients will often require surgery for alleviation of symptoms. In the absence of malignancy, asymptomatic patients may be observed. Radioactive iodine, commonly used in many parts of Europe, is safe and effective and may be a reasonable option for many patients. Periodic follow-up with neck palpation and US exam is recommended for all patients.

Objective: To assess expectations for recovery and use of behavior change strategies as predictors of subsequent diet and physical activity among adults recently hospitalized for a cardiac event. Design: Quasi-experimental design in which adults with recent cardiac event-related hospitalization completed surveys assessing health behaviors and attitudes immediately post-discharge and three months later. Results: Among those completing the study (n = 323), positive expectations about recovery and more frequent use of behavior change skills predicted greater physical activity and better nutrition at follow-up. In multivariate models, baseline health behavior was a significant predictor of physical activity and fruit and vegetable intake at follow-up (alpha = 0.05). Conclusions: Individuals participating in physical activity and eating a heart-healthy diet approximately three months after cardiac hospitalization possessed behavior change skills. Early intervention is critical as health behaviors occurring just days after hospitalization predicted future health behavior.

Background— Atrial fibrillation (AF) often coexists with myocardial infarction (MI), yet its prognostic influence is disputed. Prior reports studied the relationship of AF during early hospitalization for acute MI to the risk of death and could not address the timing of AF in relation to the MI (ie, before, during, after). Furthermore, as data come mostly from clinical trials, their applicability to the community is uncertain. The aims of our study were to assess the occurrence of AF among MI patients, determine whether it has changed over time, and quantify its impact and the impact of its timing on mortality after MI. Methods and Results— This was a community-based cohort of 3220 patients hospitalized with incident (first-ever) MI from 1983 to 2007 in Olmsted County, MN. Atrial fibrillation was identified by diagnostic codes and ECG. Outcomes were all-cause and cardiovascular death. Atrial fibrillation before MI was identified in 304 patients, and 729 developed AF after MI (218 [30%] within 2 days, 119 [16%] between 3 and 30 days, and 392 [54%] >30 days post-MI). The cumulative incidence of AF after MI at 5 years was 19% and did not change over the calendar year of MI (the incidence of AF was the same regardless of when the MI occurred). During a mean follow-up of 6.6 years, 1638 deaths occurred. AF was associated with an increased risk of death (hazard ratio [95% confidence interval] 3.77 [3.37 to 4.21]), independently of clinical characteristics at the time of MI and heart failure. This risk differed markedly according to the timing of AF, and was the greatest for AF occurring >30 days post MI (hazard ratio [95% confidence interval] 1.63 [1.37 to 1.93] for AF within 2 days, 1.81 [0.45 to 2.27] for AF between 3 and 30 days, and 2.58 [2.21 to 3.00] for AF >30 days post MI). Conclusions— In the community, AF is frequent in the setting of MI. Atrial fibrillation carries an excess risk of death, which is the highest for AF developing >30 days after MI.

Median arcuate ligament syndrome (MALS) is often diagnosed when idiopathic, episodic abdominal pain is associated with dynamic compression of the proximal celiac artery by fibers of the median arcuate ligament. The character of the abdominal pain is often postprandial and associated with gradual weight loss from poor food intake, suggestive of chronic mesenteric ischemia. However, the pathognomonic imaging feature of dynamic, ostial celiac artery compression with expiration does not consistently predict clinical improvement from revascularization. Proposed but unproven pathophysiological mechanisms include neurogenic pain from compression of the splanchnic nerve plexus and intermittent ischemia from compression of the celiac artery. Alterations in blood flow and ganglion compression are both associated with delayed gastric emptying, another physiological correlate of the clinical syndrome. Published reports describe a variable response to revascularization and nerve plexus resection suggest a need for translational research to better characterize this poorly understood clinical entity. We illustrate the current gaps in our knowledge of MALS with the case of a 51-year-old woman with a 4-year history of chronic abdominal pain who responded to a combination of ganglion resection and celiac artery reconstruction.