Only a minority of patients with SCAD who undergo genetic evaluation have a likely pathogenic mutation identified on gene panel testing. Even fewer exhibit clinical features of connective tissue disorder. These findings underscore the need for further studies to elucidate the molecular mechanisms of SCAD.

Background Cardiovascular disease among hemodialysis (HD) patients is linked to poor outcomes. The Acute Dialysis Quality Initiative Workgroup proposed echocardiographic (ECHO) criteria for structural heart disease (SHD) in dialysis patients. The association of SHD with patient-important outcomes is not well defined. Objectives We determined prevalence of ECHO determined SHD and its association with survival among incident HD patients. Methods We analyzed patients initiating chronic HD from 2001-2013 who underwent ECHO ≤ 1 month prior to or ≤ 3 months following HD initiation (n = 654). Results Mean patient age was 66 ± 16 years, and 60% of patients were male. ECHO findings that met 1 or more and ≥ 3 of the new criteria were discovered in 87% and 54% of patients, respectively. Over a median of 2.4 years, 415 patients died: 108 (26%) died within 6 months. Five-year mortality was 62%. Age- and gender-adjusted structural heart disease variables associated with death were left ventricular ejection fraction (LEVF) ≤ 45% (HR 1.48, CI 1.20-1.83) and right ventricular (RV) systolic dysfunction (HR 1.68, CI 1.35-2.07). An additive of higher death risk included LVEF ≤ 45% and RV systolic dysfunction rather than neither (HR 2.04, CI 1.57-2.67; p = 0.53 for test for interaction). Following adjustment for age, gender, race, diabetic kidney disease, and dialysis access, RV dysfunction was independently associated with death (HR 1.66; CI 1.34-2.06; p < 0.001). Conclusions SHD was common in our hemodialysis study population, and RV systolic dysfunction independently predicted mortality.

Chronic heart disease induces remodeling of cardiac tissue and associated neuronal components. Treatment of chronic heart disease often involves pharmacological blockade of adrenergic receptors. This study examined the specific changes in neuronal sensitivity of guinea pig intrinsic cardiac neurons to autonomic modulators in animals with chronic cardiac disease, in the presence or absence of adrenergic blockage. Myocardial infarction (MI) was produced by ligature of the coronary artery and associated vein on the dorsal surface of the heart. Pressure overload (PO) was induced by a banding of the descending dorsal aorta (∼20% constriction). Animals were allowed to recover for 2 wk and then implanted with an osmotic pump (Alzet) containing either timolol (2 mg·kg(-1)·day(-1)) or vehicle, for a total of 6-7 wk of drug treatment. At termination, intracellular recordings from individual neurons in whole mounts of the cardiac plexus were used to assess changes in physiological responses. Timolol treatment did not inhibit the increased sensitivity to norepinephrine seen in both MI and PO animals, but it did inhibit the stimulatory effects of angiotensin II on the norepinephrine-induced increases in neuronal excitability. Timolol treatment also inhibited the increase in synaptically evoked action potentials observed in PO animals with stimulation of fiber tract bundles. These results demonstrate that β-adrenergic blockade can inhibit specific aspects of remodeling within the intrinsic cardiac plexus. In addition, this effect was preferentially observed with active cardiac disease states, indicating that the β-receptors were more influential on remodeling during dynamic disease progression.

P latypnea-orthodeoxia syndrome (POS) is an uncommon condition of positional dyspnea (platypnea) and hypoxemia (orthodeoxia). The symptoms occur when the patient is upright and resolve quickly with recumbency. These findings are the opposite of those typically seen in cases of advanced heart failure and can pose a diagnostic dilemma.Even though POS was first described in the late 1940s, 1 the pathophysiologic triggers of orthodeoxia and platypnea are still not completely understood. It appears that both a functional component and an anatomic component are required.2 The syndrome has been associated with cardiac, pulmonary, abdominal, and vascular disease (functional component) in conjunction with a shunt (anatomic component). 2 The most frequently described cause is right-to-left interatrial shunting from a patent foramen ovale (PFO) or an atrial septal defect (ASD) in the presence of pulmonary hypertension.3 Positional variation in the degree of shunting in these situations remains incompletely understood. It is believed that the upright position changes or stretches the conformation of the interatrial communication, increasing the proportion of blood flow from the inferior vena cava through the defect and into the left atrium. 3 We report our experience in treating a patient who presented with POS in the absence of substantial pulmonary hypertension. Case ReportIn September 2013, an 83-year-old woman with a history of paroxysmal atrial fibrillation was admitted to the hospital after several weeks of progressive positional dyspnea that worsened with standing and improved with lying supine. On admission, the patient's pulse oximetry on room air was 96% while supine and 81% while standing. Physical examination was noteworthy for marked kyphoscoliosis. Computed tomographic evaluation for lung disease revealed a tortuous thoracic aorta with otherwise normal lung parenchyma. The patient's arterial blood gases on room air showed a significant drop in arterial oxygen tension upon postural change (from lying down to standing), confirming our suspicion of POS (Table I).A transthoracic echocardiogram revealed normal pulmonary artery pressure, with an atrial bidirectional shunt. A transesophageal echocardiogram revealed an ASD of moderate size (area, 2.2 cm 2 ) (Fig. 1), together with bidirectional shunting while the patient was supine and sedated.

Background Nonchicken wing left atrial appendage (LAA) morphology is associated with higher risk for stroke in patients with atrial fibrillation (AF) than chicken wing (CW) morphology. Objective Assess whether LAA morphology predicts the formation of LAA thrombus independent of age, sex, presenting rhythm, left ventricular ejection fraction (LVEF), or anticoagulant use. Methods A cross‐sectional analysis was performed on patients prospectively enrolled in the Vanderbilt LAA Registry or presenting for transesophageal echocardiogram (TEE) between January 1, 2015, and November 1, 2017 (n = 306). Two physicians independently reviewed TEEs interpreted as having LAA thrombus. Determination of LAA morphology, ejection velocity, and presence of thrombus (n = 102) were based on 0°, 45°, 90°, and 135° TEE views. The control cohort (n = 204) included consecutive AF patients undergoing TEE without LAA thrombus. Results LAA morphology in patients with LAA thrombus was: 35% windsock, 47% broccoli, and 12% CW. Windsock (odds ratio [OR], 4.0; 95% confidence interval [CI]: 1.7–9.3, p = .001) and broccoli (OR, 6.6; 95% CI: 2.6–16.6; p < .001) morphology were higher risk for thrombus compared to CW. Female sex predicted higher‐odds for LAA thrombus (OR, 2.6; 95% CI: 1.4–4.8; p = .002) as did LAA‐EV < 20 cm/s (OR, 11.12; 95% CI: 5.6–22.1). Anticoagulation use (OR, 0.5; 95% CI: 0.3–0.9; p = .03) and higher LVEF (OR, 0.95; 95% CI: 0.93–0.98; p < .001) were associated with lower risk. In patients with a CW morphology who had LAA thrombus, 4 of the 7 had an LAA‐EV < 20 cm/s and acute systolic heart failure with LVEF < 30% or active malignancy. In multivariable linear regression analysis controlling for presenting rhythm, anticoagulant use, age, sex, and LVEF, CW morphology appears relatively protective from LAA thrombus (p = .001). Conclusion CW LAA morphology appears relatively protective against the formation of LAA thrombus.