Prognostic Value of Computed Tomography Versus Echocardiography Derived Right to Left Ventricular Diameter Ratio in Acute Pulmonary Embolism

BackgroundComputed Tomography (CT) Pulmonary Angiography is the most commonly used diagnostic study for acute pulmonary embolism (PE). Echocardiogram (ECHO) is also used for risk stratification in acute PE, however the diagnostic performance of CT versus ECHO for risk stratification remains unclear.MethodsCT and ECHO right ventricle (RV) and left ventricle (LV) diameters were measured in a retrospective cohort of patients with acute PE. RV:LV diameter ratios were calculated and correlation between CT and ECHO RV:LV ratio was assessed. Sensitivity and specificity for the composite adverse events endpoint of mortality, respiratory failure requiring intubation, cardiac arrest, or shock requiring vasopressors within 30 days of admission were assessed for CT or ECHO derived RV:LV ratio alone and in combination with biomarkers (troponin or B-type natriuretic peptide).ResultsA total of 74 subjects met the inclusion criteria and had a mean age of 62±18 years. The proportion of patients with RV:LV >1 was similar when comparing CT (37.8%) versus ECHO (33.8%) (P = 0.61). A statistically significant correlation was found between CT derived and ECHO derived RV:LV diameter ratio (r = 0.832, P < 0.001). The sensitivity and specificity to predict 30-day composite adverse events for CT versus ECHO derived RV:LV diameter ratio >1 together with positive biomarker status was similar with sensitivity and specificity of 87% and 41% versus 87% and 42%, respectively.ConclusionsIn patients with acute PE, CT and ECHO RV:LV diameter ratio correlate well and identify similar proportion of PE patients at risk for early adverse events. These findings may streamline risk stratification of patients with acute PE.     

Risks of adverse events in patients with orthostatic intolerance undergoing surgery with general anesthesia

Clinical Autonomic Research - Orthostatic intolerance (OI) is a group of disorders characterized by symptoms that occur upon standing and resolve with recumbence. Although well established but not...     

Oral Anticoagulation Use in High-Risk Patients Is Improved by Elimination of False-Positive and Inactive Atrial Fibrillation Cases

BackgroundMultiple registries have reported that >40% of high-risk atrial fibrillation patients are not taking oral anticoagulants. The purpose of our study was to determine the presence or absence of active atrial fibrillation and CHA₂DS₂-VASc (Congestive heart failure, Hypertension, Age ≥75 y, Diabetes mellitus, prior Stroke [or transient ischemic attack or thromboembolism], Vascular disease, Age 65-74 y, Sex category) risk factors to accurately identify high-risk atrial fibrillation (CHA₂DS₂-VASc ≥2) patients requiring oral anticoagulants and the magnitude of the anticoagulant treatment gap.MethodsWe retrospectively adjudicated 6514 patients with atrial fibrillation documented by at least one of: billing diagnosis, electronic medical record encounter diagnosis, electronic medical record problem list, or electrocardiogram interpretation.ResultsAfter review, 4555/6514 (69.9%) had active atrial fibrillation, while 1201 had no documented history of atrial fibrillation and 758 had a history of atrial fibrillation that was no longer active. After removing the 1201 patients without a confirmed atrial fibrillation diagnosis, oral anticoagulant use in high-risk patients increased to 71.1% (P < .0001 compared with 62.9% at baseline). Oral anticoagulant use increased to 79.7% when the 758 inactive atrial fibrillation patients were also eliminated from the analysis (P < .0001 compared with baseline). In the active high-risk atrial fibrillation group, there was no significant difference in the use of oral anticoagulants between men (80.7%) and women (78.8%) with a CHA₂DS₂-VASc ≥2, or in women with a CHA₂DS₂-VASc ≥3 (79.9%).ConclusionsCurrent registries and health system health records with unadjudicated diagnoses over-report the number of high-risk atrial fibrillation patients not taking oral anticoagulants. Expert adjudication identifies a smaller treatment gap than previously described.     

Role of implantable loop recorders in patients with postural orthostatic tachycardia syndrome

Introduction

We previously reported on a subgroup of postural orthostatic tachycardia syndrome (POTS) patients who may also have features of neurocardiogenic syncope as well. In this subgroup of patients, we found syncope and presyncope were predominant clinical features. To understand the mechanism of syncope in this subgroup, we identified 39 patients who underwent loop recorder insertion.

Methods

We reviewed charts of 450 patients who had POTS and syncope seen at the University of Toledo Medical Center from 2003 to 2017. Thirty‐nine patients had at least four episodes of syncope in the last 6 months and were included for this study. All of these patients had a prior evaluation with a Holter and an event monitor which were inconclusive.

Results

Thirty‐nine patients, 33 (85%) women, aged 20–46 years, were included in this study. All patients demonstrated prolonged asystole (>6 seconds) or severe bradycardia (heart rate < 30 beats/min) during their syncope on implantable loop recorder (IRL). Fifteen patients demonstrated an asystole of >10 seconds and also had prolonged and convulsive syncope. All patients had abrupt syncope without any warning sign. All patients underwent dual‐chamber pacemaker implantation using a closed loop stimulation algorithm. Syncope were completely eliminated in all patients following pacemaker implantation; however, they continued to have orthostatic tachycardia.

Conclusion

POTS patients with unusually frequent syncope should be considered for ILR implantation if other monitoring modalities like 48‐hour Holter monitor or event recorder are inconclusive. ILR may identify a subgroup of POTS patients who may benefit from pacemaker implantations.

     

The role of autoantibodies in the syndromes of orthostatic intolerance: a systematic review

Orthostatic intolerance is defined as the provocation of symptoms upon standing, commonly caused by neurogenic orthostatic hypotension (OH) and postural tachycardia syndrome (POTS), the etiology for which has not been fully uncovered yet. Many reports have described the occurrence of dysautonomia, orthostatic intolerance and POTS following febrile illness, presumably viral and post-vaccine. Furthermore, patients with dysautonomia have higher rates of autoimmune disorders such as Hashimoto thyroiditis and SLE. Recent evidence has shown the presence of adrenergic and cholinergic receptor antibodies in patients with POTS and orthostatic hypotension. In patients with cholinergic receptor antibodies, higher titers correlate with the disease severity. Few reports have shown that immunomodulation therapy resulted in significant improvement in symptoms. In this article, we review the available literature correlating autoimmunity with orthostatic intolerance syndromes. Future studies are warranted to evaluate the prevalence of such antibodies and examine different treatment modalities in this sub group of patients.     

Hemophagocytic Lymphohistiocytosis in the Elderly

Hemophagocytic lymphohistiocytosis (HLH) is a rare disease of massive, dysregulated cytokine release and secondary multiorgan failure and is associated with high mortality. Primary HLH occurs predominately in infants and young children with a genetic predisposition. Acquired HLH is less well characterized and usually occurs in younger adults in the setting of severe inflammation triggered by infection or malignancy. Little is known about the disease in elderly. We report 3 patients >50 years old who presented with multiorgan failure and shock without an identifiable source and were ultimately diagnosed with acquired HLH. We performed a literature review of HLH in adults >50 years of age and identified an additional 68 cases. Mean age was 62 years, with male predominance. Most cases were triggered by infection (49%) followed by malignancy (27%). Nineteen patients were treated with the HLH-94 protocol, 11 received corticosteroids and the remainder received non-HLH specific interventions. Overall mortality was 62%.     

Vasovagal syncope–role of closed loop stimulation pacing

The benefit of conventional pacing in vasovagal syncope remains controversial and is currently recommended for patients with recurrent syncope and documented asystole. In the last two decades, a growing body of evidence has emerged supporting the use of a new sensing technique called closed loop stimulation or CLS, to treat refractory vasovagal syncope. CLS uses a sensing algorithm that can detect variation in cardiac contractility and respond to drop in blood pressure by increasing the heart rate. Multiple observational and randomized studies have assessed its efficacy and showed its superiority to conventional pacing in reducing the burden of syncopal attacks in patients with cardio-inhibitory vasovagal syncope.     

Role of closed loop stimulation pacing (CLS) in vasovagal syncope

Vasovagal syncope (VVS) or neurocardiogenic syncope is defined by transient loss of consciousness with spontaneous and rapid recovery. Recently, a closed loop stimulation (CLS) pacing system has emerged as a new strategy which appears superior to conventional pacing for patients with refractory syncope. However, its efficacy remains of considerable debate and large randomized controlled clinical trials are needed. Between 2002 and 2017, 12 total studies evaluated the use of CLS pacing in patients with refractory VVS, and are summarized in this article.     

Ivabradine in the treatment of postural tachycardia syndrome (POTS), a single center experience

1 Background

Ivabradine is a selective I_f channel blocker that reduces heart rate without affecting other cardiovascular functions. In case reports and case series, it was shown to improve symptoms in patients with postural tachycardia syndrome (POTS).

2 Methodology and results

This retrospective study examined patients who were diagnosed with POTS and received ivabradine as part of their treatment. Forty‐nine patients (47 females, 95.9%) received ivabradine. The average age was 35.1 ± 10.35 years. The most common symptoms were palpitations and lightheadedness and both improved significantly, 88.4% and 76.1% response rate, respectively. A total of 38 patients reported improvement in their symptoms. In addition, ivabradine resulted in an objective decrease in sitting and standing heart rate (78.1 ± 10.7 vs 72.5 ± 7.6, P‐value: 0.01) and (107.4 ± 14.1 vs 95.1 ± 13.7, P‐value: < 0.001), respectively, with no significant change in blood pressure. The most common reported side effect was luminous phenomena/visual brightness occurring in nine patients. However, none of the patients stopped ivabradine due to side effects.

3 Conclusion

Our study shows that ivabradine is likely to be effective in treating patients with POTS. Nearly 78% of our cohort reported a significant improvement in symptoms with no major adverse effects reported. A future randomized, placebo‐controlled trial is warranted.