Research Spotlight

Roberts, W. C., N. Ather and J. M. Guileyardo (2020). “Examining Hearts Containing Left Ventricular Assist Devices at Necropsy.” Am J Cardiol 125(2): 244-250.

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There are no publications describing hearts at necropsy containing left ventricular assist devices (LVADs). The purpose was to study the relation of the LVAD cannula to the left ventricular (LV) cavity and wall. We studied the hearts at necropsy of 15 adults who had an LVAD inserted from 4 to 1,423 days (median 60) earlier. In 13 patients, the cannula had been inserted at an angle to the major longitudinal axis of the LV chamber, and in 11 patients, the orifice margin of the cannulas contacted the LV mural endocardium. In 3 patients, the LVAD cannula was inserted into the posterior wall, and, in another into the anterior wall. In the remaining 11 patients, the cannula had been inserted into the LV apex. Despite the insertion of the cannulas into the LV apex, the direction of the insertion was not into the longitudinal axis of the LV cavity in 9 patients. These unusual insertions in some patients may have altered flow into the orifice of the cannula; in others, based on their long postoperative survival, physiologic consequences were almost certainly absent. The presence of considerable quantities of subepicardial adipose tissue and pericardial adhesions from previous cardiac procedures (mainly coronary bypass) potentially interfered with achieving proper alignment of the LVAD cannula during its insertion. Misalignment of the cannulas of the LVAD in the LV cavity appears to be rather frequent.

Ramsay, M. A. (2020). “Non-invasive monitoring is coming the full circle, making our patients safer!” J Clin Monit Comput Jan 18. [Epub ahead of print].

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Non-invasive monitoring is becoming more accurate, more available and mobile. The clinical advantage that this developing technology provides is that the data may be monitored continuously; relatively unobtrusively, and transmitted directly to the caregiver. The downside of being non-invasive has been the potential loss of accuracy in the data displayed. This has been overcome in the measurement of oxygen saturation of hemoglobin by pulse oximetry, in that treatment will be instigated by a decline in oxygen saturation without necessarily an arterial blood gas analysis being performed. The development of pulse oximetry to measure hemoglobin levels (SpHb) has relied on “trend accuracy” to indicate the need for a confirmatory laboratory analysis of hemoglobin level. The study by Applegate et al. [1] confirms the trend accuracy of SpHb as an indication to perform a laboratory confirmation of hemoglobin level. This will lead to earlier laboratory screening, so that developing adverse conditions, such as postoperative bleeding, may be identified at a time that major events, such as failure to rescue can be avoided. This increased availability of non-invasive technology will make patients safer both in our hospitals and at home.

Peterson, G. C., A. Preston, J. Frieder, X. Wang and S. Y. Paek (2020). “Analysis of Characteristics and Trends in Treatment Response of Hidradenitis Suppurativa Patients: A Southern US Cohort Study.” Dermatology Jan 14. [Epub ahead of print].

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BACKGROUND: Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that has a substantial impact on patients’ quality of life. As the exact pathogenesis remains unclear, treatment is complex and not yet standardized. OBJECTIVES: The aim of this study was to describe patient characteristics and to broadly examine trends in treatment response of various therapeutic strategies in patients with HS in a single academic referral center in the southern USA. METHODS: A retrospective chart review was conducted of a cohort of HS patients seen in a faculty general dermatology practice with academic affiliation to Baylor University Medical Center in Dallas, TX, between February 2015 and February 2018. Patient demographics, clinical features, prescribed treatments, and response to treatment were analyzed using the Pearson chi2 test or Fisher exact test, and by the Mann-Whitney U test for categorical and continuous variables, respectively. RESULTS: A total of 149 patients (113 females, 36 males) were included. Hurley stages I, II, and III were diagnosed in 29.6, 36.5, and 33.9% of patients, respectively. 44.2% of patients had a positive family history of HS, 39.5% of patients were current or former smokers, and 52.8% reported alcohol use. 80.9% of patients were overweight or obese (BMI >/=25), compared to 68.5% in Texas in 2016 (p = 0.0012). The most frequently prescribed treatments were oral antibiotic therapy (83.9%), topical antibiotic therapy (74.5%), metabolic medications such as metformin/zinc (67.1%), intralesional Kenalog (63.1%), and biologic therapies (tumor necrosis factor-alpha inhibitors; TNF-alpha inhibitors; 49%). In examining the response rate, patients with disease localized to the buttocks had significantly higher response rates (60.4 vs. 25%, p = 0.043) and approached statistical significance in responders versus nonresponders in treatment with biologics (p = 0.0632) when compared against all other treatments. CONCLUSIONS: HS is a complex inflammatory skin condition associated with obesity and smoking. In this cohort, the most frequently prescribed therapies were oral and topical antibiotics. However, the use of biologic agents (TNF-alpha inhibitors) appears to be associated with the most significant treatment response. KEY POINTS: This is the first study to evaluate trends in treatment response of various therapeutic strategies in HS patients at an academic referral center in Dallas, TX, a unique geographic region of the southern USA. Biologic therapy (TNF-alpha inhibitor) appears to be associated with the most significant treatment response.

Packer, M., C. S. P. Lam, L. H. Lund and M. M. Redfield (2020). “Interdependence of Atrial Fibrillation and Heart Failure With a Preserved Ejection Fraction Reflects a Common Underlying Atrial and Ventricular Myopathy.” Circulation 141(1): 4-6.

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Atrial fibrillation (AF) and heart failure with a preserved ejection fraction (HFpEF) are closely intertwined disorders that afflict millions of people, many of whom are obese or have diabetes mellitus or other proinflammatory conditions. Conceivably, the convergence of AF and HFpEF might be explained by 2 distinctly different frameworks. On the one hand, it is possible that each phenotype might lead sequentially to the other (ie, the increased left ventricular [LV] filling pressure in HFpEF may cause left atrial [LA] dilatation that triggers AF, and conversely, the rapid heart rate that accompanies AF might lead to LV fibrosis, although there is little evidence to support this hypothesis). On the other hand, and more likely, the 2 disorders may be parallel manifestations of the same underlying myocardial disease, which causes AF (because it affects the LA) and HFpEF (because it afflicts the LV) . . . AF and HFpEF demonstrate an exceptionally high degree of clinical and epidemiological convergence. Regardless of which disorder presents first, both are or will soon become evident in the same patients. AF and HFpEF appear to both be manifestations of a common underlying atrial and ventricular myopathy that is triggered when a systemic inflammatory or metabolic disorder causes coronary microvascular dysfunction and fibrosis of the atrial and ventricular myocardium, a process that may be mediated or exacerbated by inflammation in the adjoining epicardial adipose tissue. (Excerpts from text, p. 4, 6; no abstract available.)

Packer, M. (2020). “Potential Role of Atrial Myopathy in the Pathogenesis of Stroke in Rheumatoid Arthritis and Psoriasis: A Conceptual Framework and Implications for Prophylaxis.” J Am Heart Assoc 9(3): e014764.

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Both rheumatoid arthritis (RA) and psoriasis are accompanied by an increased risk of stroke, which cannot be explained by an increased prevalence of traditional cardiovascular risk factors that are focused on atherosclerosis. Instead, the risk of stroke is likely to be related to an effect of systemic inflammation to promote the development of an atrial myopathy, resulting in blood stasis within the left atrium (LA), thrombus formation, and systemic thromboembolism. The systemic inflammatory process in RA and psoriasis can directly impair the integrity of the endothelium of the coronary microcirculation of the atrial myocardium. In addition, systemic inflammation can cause expansion of the epicardial adipose tissue adjacent to the LA; the secretion of proinflammatory adipocytokines from the epicardial fat depot can exaggerate the adverse structural and functional changes in the LA, leading to the atrial myopathy that provides the substrate for thromboembolic stroke. Interventions that are directed toward alleviation of the atrial myopathy and the resulting risk of thrombus formation are worthy of further evaluation in reducing the burden of cerebrovascular disease in patients with RA and psoriasis. (Excerpt from text, n.p.; no abstract available.)