Retained cardiac implantable electronic device fragments are not associated with magnetic resonance imaging safety issues, morbidity, or mortality after orthotopic heart transplant.

BACKGROUND: Cardiac implantable electronic device therapy (CIED) has revolutionized treatment for advanced heart failure. Most patients considered for orthotopic heart transplantation (OHT) are treated with implantable cardioverter defibrillators, cardiac resynchronization therapy, or both. These CIEDs are surgically extracted at the time of transplant. Occasionally, CIEDs are incompletely removed. Little is known about the outcomes of post-OHT patients with retained CIED fragments. METHODS: We identified 200 consecutive patients that underwent OHT at our institution between April 2006 and December 2014 and performed a retrospective analysis of available radiographic images and clinical records. Chest radiographs prior to and following OHT were reviewed for the presence of CIED or retained CIED fragments. The outcomes of patients with retained CIED fragments that had subsequent magnetic resonance imaging (MRI) studies performed were further investigated. RESULTS: One hundred eighty of 200 patients were identified as having CIED prior to OHT, of which 29 had retained CIED fragments after OHT. Most retained CIED fragments originated from superior vena cava defibrillator coils. There were no adverse events in the retained CIED fragment cohort, and survival was unaffected. Ten patients with retained CIED fragments safely underwent a total of 28 MRIs after OHT, all of diagnostic quality. CONCLUSION: Retained CIED fragments are not associated with adverse events or increased mortality after OHT. Diagnostic MRI has been safely performed in patients with retained CIED fragments after incomplete device extraction. Retrieval of these fragments prior to MRI does not appear warranted given the demonstrated safety and preserved image quality in this population.

Screening for connective tissue disease in pulmonary arterial hypertension.

OBJECTIVES: To evaluate the utility of anti-nuclear antibody (ANA) levels in distinguishing the cause of pulmonary arterial hypertension as idiopathic (IPAH) or connective tissue disease related (CTD-PAH). METHODS: We retrospectively identified patients with IPAH or CTD-PAH seen between 2010 and 2012 at our institution. Medical records were reviewed for demographic and clinical data and laboratory values. RESULTS: Of 115 patients identified, 65 (56%) had IPAH and 50 (44%) had CTD-PAH. The mean age was 59 years and most of the patients (76%) were women. Most patients (64%) were in World Health Organization functional class III or IV. Compared with the IPAH group, the CTD-PAH group had significantly increased B-type natriuretic peptide levels (635 vs 325 pg/mL; P = 0.02) and decreased pulmonary vascular resistance (6 vs 9 WU; P = 0.04). The median ANA level was significantly higher in the CTD-PAH group than the IPAH group (7 vs 0 U; P < 0.001). The area under the receiver operating characteristic curve for a positive ANA to predict CTD-PAH was 0.91 (P < 0.001). A cutoff of 5 U for predicting ANA provided an optimal specificity of 94% and a sensitivity of 70%. The resulting likelihood ratio using the same cutoff was 12 (P < 0.001), or a positive predictive value of 91% with a negative predictive value of 79%. CONCLUSIONS: In this selected cohort of patients, a quantitative ANA value >5 U may be useful in distinguishing CTD-PAH from IPAH, but a lower level does not confidently exclude CTD-PAH.

Sex differences in pulmonary arterial hypertension: role of infection and autoimmunity in the pathogenesis of disease.

Registry data worldwide indicate an overall female predominance for pulmonary arterial hypertension (PAH) of 2-4 over men. Genetic predisposition accounts for only 1-5% of PAH cases, while autoimmune diseases and infections are closely linked to PAH. Idiopathic PAH may include patients with undiagnosed autoimmune diseases based on the relatively high presence of autoantibodies in this group. The two largest PAH registries to date report a sex ratio for autoimmune connective tissue disease-associated PAH of 9:1 female to male, highlighting the need for future studies to analyze subgroup data according to sex. Autoimmune diseases that have been associated with PAH include female-dominant systemic sclerosis, systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, and thyroiditis as well as male-dominant autoimmune diseases like myocarditis which has been linked to HIV-associated PAH. The sex-specific association of PAH to certain infections and autoimmune diseases suggests that sex hormones and inflammation may play an important role in driving the pathogenesis of disease. However, there is a paucity of data on sex differences in inflammation in PAH, and more research is needed to better understand the pathogenesis underlying PAH in men and women. This review uses data on sex differences in PAH and PAH-associated autoimmune diseases from registries to provide insight into the pathogenesis of disease.

Von Willebrand factor multimer quantitation for assessment of cardiac lesion severity and bleeding risk.

BACKGROUND: von Willebrand factor (VWF) multimer quantitation has been utilized in the assessment of valvular heart disease, however, there is no standardized method for quantitation. We compared three methods of assessment which utilized a normal plasma control. METHODS: We analyzed 476 samples and their control plasma from 368 patients with valvular heart disease, hypertrophic cardiomyopathy, or LVAD therapy, and 27 normal subjects. VWF multimers were assessed as normalized VWF multimer ratios (NMR) of gel bands >15/2-15 (NMR15) or gel bands >10/2-10 (NMR10). Associations of VWF laboratory and multimeric assessments with cardiac lesion severity and acquired bleeding were investigated. RESULTS: Abnormal multimers were present in 78% of patients with moderate to severe hemodynamic abnormalities compared to 19% of patients with normal or mildly abnormal hemodynamics. NMR showed strong association with severe cardiac lesions (NMR15: OR 15.29, CI 9.04-27.18; NMR10: OR 14.18, CI 8.88-23.21). PFA-CADP was strongly associated with moderate to severe cardiac lesions (OR 14.91, CI 9.08-24.50). PFA-CADP and NMR15 showed excellent ability to discriminate ≥moderate (AUC 0.86, CI 0.83-0.89 and 0.83, CI 0.79-0.87 respectively) and severe cardiac lesions (AUC 0.84, CI 0.81-0.88 and 0.85, CI 0.81-0.88 respectively). NMR was less strongly associated with bleeding (OR 4.01 for NMR10, CI 2.49-6.58). CONCLUSION: Quantification of VWF multimers may provide clinical utility in circumstances where clinical estimation of cardiac lesion severity is challenging, such as with dysfunctional prosthetic valves. The presence of abnormal VWF multimers is associated with bleeding, however further quantitation provided only modest improvement in risk stratification.

Pacemaker Placement in Patients with Stroke-Mediated Autonomic Dysregulation.

Lateral medullary syndrome (LMS) is an ischemic disease of the medulla oblongata, which involves the territory of the posterior inferior cerebellar artery. Lateral medullary syndrome is often missed as the cause of autonomic dysregulation in patients with recent brain stem stroke. Due to the location of the baroreceptor regulatory center in the lateral medulla oblongata, patients with LMS occasionally have autonomic dysregulation-associated clinical manifestations. We report a case of LMS-associated autonomic dysregulation. The case presented as sinus arrest and syncope, requiring permanent pacemaker placement. A dual-chamber pacemaker was placed, after failure of conservative measures to alleviate the patient's symptoms. Our case shows the importance of recognizing LMS as a potential cause for life-threatening arrhythmias, heart block, and symptomatic bradycardia. Placement of permanent pacemaker may be necessary in some patients with LMS presenting with syncope, secondary to sinus arrest.

Revisiting propafenone toxicity.

Propafenone is a Vaughan Williams class 1c antiarrhythmic medication widely used for treatment of arrhythmias. Although the long-term safety of propafenone use has not been established, it is commonly used for treatment of atrial fibrillation in patients with no structural heart disease. Propafenone is well known as pill-in-the-pocket treatment for its effect in terminating paroxysmal episodes of atrial fibrillation. Herein, we discuss an unusual adverse reaction to propafenone in a patient who presented with symptomatic bradycardia and hypotension. The aim of this article is to increase physician awareness for propafenone toxicity and its management, with a focused literature review on propafenone pharmacotherapy.

Incidence of Sustained Ventricular Tachycardia in Patients with Prolonged QTc After the Administration of Azithromycin: A Retrospective Study.

BACKGROUND: Azithromycin has been associated with abnormalities of cardiac repolarization and development of torsades de pointes. Observational data suggest that the risk of death from cardiovascular causes is increased in patients taking azithromycin. Little is known regarding the risk of ventricular arrhythmia in patients with prolongation of the corrected QT interval who receive azithromycin. OBJECTIVE: The purpose of this study was to determine the incidence of sustained ventricular tachycardia in patients with prolonged corrected QT (QTc) who subsequently received azithromycin. METHODS: We performed a retrospective cohort analysis of the incidence of sustained ventricular tachycardia in patients with prolonged QTc (greater than 450 ms) who successively received intravenous (IV) and/or oral azithromycin. Patients hospitalized in a tertiary care teaching hospital between November 2009 and June 2012 were included in the study. The primary outcome was sustained ventricular tachycardia documented in patients on telemetry. RESULTS: Of the 103 patients enrolled in the study, only one patient experienced the primary outcome (0.97 %). The event occurred 1 day after the administration of a single dose of 500 mg IV azithromycin. CONCLUSION: The risk of sustained ventricular tachycardia was 0.97 % in our cohort of patients with prolonged QTc who subsequently received azithromycin. Given the small size of this study, additional research is needed to determine the true incidence of arrhythmia in the population.

A heart of stone: a case of acute development of cardiac calcification and hemodynamic collapse.

Acute cardiac calcification is a clinical entity that may develop over days to months and is usually localized to areas of healed myocardial infarction, cardiac surgery or trauma. We present an unusual case of rapidly developing non-ischemic cardiac calcification in the setting of sepsis and end stage renal disease resulting in acute diastolic dysfunction and cardiac collapse diagnosed by computed tomography (CT) and confirmed by autopsy. We propose that dedicated cardiac CT may provide the most accurate means to detect cardiac calcification.

Assessing the available techniques for testing myocardial viability: what does the future hold?

Left ventricular dysfunction in the setting of severe coronary artery disease poses a major diagnostic and therapeutic dilemma. While this clinical scenario is generally associated with poor outcomes, some but not all patients benefit from coronary revascularization. For example, patients with severe, transmural myocardial infarctions may derive little or no functional benefit from revascularization, as the underlying myocardium is irreversibly scarred. Furthermore, these patients may be exposed to high procedural risks with a low likelihood of deriving any perceivable benefit. Conversely, hibernating myocardium reflects a substrate whereby the nonfunctioning myocytes are chronically ischemic but may be viable. Existing data are somewhat inconclusive with regard to the benefits of performing viability testing in patients with ischemic cardiomyopathy. While this testing may predict regional and global functional myocardial recovery, the ability of viability studies to predict survival and prognosis remains unproven in prospective studies to date. Yet, viability testing may still be a valuable tool to guide therapeutic options in selected patients. A variety of noninvasive viability tests are available and newer technologies, such as PET and cardiac MRI, are likely to advance the scientific field in years to come.