Two Perspectives of the Appropriate Use Criteria in Cardiology Practice: Advantageous and Useful or Limiting and Harmful?

The appropriate use criteria (AUC) has become an integral part of the cardiologist's daily practice and have evolved greatly since their inception over a decade ago. However, as health care costs continue to rise, the AUC has come to play an even more pivotal role in the way medicine-specifically cardiology-is practiced today. This editorial describes two opposing viewpoints commonly held by practicing clinicians of the AUC. Written from the perspective of two fellows-in-training looking ahead at the challenges and opportunities of clinical practice (under the auspices of several experienced clinicians and leaders of the American College of Cardiology), this article provides a fresh perspective on the impact AUC has on our patients, clinicians, and the health care system.

Optimization of stent implantation using a high pressure inflation protocol.

BACKGROUND: High-pressure inflation is the universal standard for stent deployment but a specific protocol for its use is lacking. We developed a standardized "pressure optimization protocol" (POP) using time to inflation pressure stability as an endpoint for determining the required duration of stent inflation. OBJECTIVES: The primary study purpose was to determine the stent inflation time (IT) in a large patient cohort using the standardized inflation protocol, to correlate various patient and lesion characteristics with IT, and ascertain in an in vitro study the time for pressure accommodation within an inflation system. METHODS: Six hundred fifteen stent implants in 435 patients were studied. Multivariate analysis was performed to determine predictors of longer ITs. In an in vitro study, various stents and balloons were inflated in air to determine the pressure accommodation time of the inflation system. RESULTS: The mean stent IT was 104 ± 41 sec (range 30-380 sec). Stent length was the only predictor of prolonged stent inflation. The "accommodation time" in vitro of the stent inflation system itself was 33 ± 24 sec. The protocol was safe requiring premature inflation termination in <3% of stent implants. No serious adverse events occurred. CONCLUSIONS: Achieving stable inflation pressure requires on average over 100 sec and may require several minutes in individual cases. Stent length increases IT. These results suggest that the widespread practice of rapid inflation/deflation may not be sufficient to fully expand the stent and that the use of a pressure stability protocol will allow for safe, predictable, and more complete stent deployment. © 2015 Wiley Periodicals, Inc.

PseudoBartter syndrome in eating disorders.

OBJECTIVE: PseudoBartter's syndrome, a complex pattern of seemingly unrelated metabolic abnormalities, is frequently seen in patients with eating disorders, particularly those who indulge in purging behaviors. We present two cases that, despite divergent background histories and clinical presentations, possess the unifying pathophysiology that ultimately leads to this syndrome. METHOD: Case report and review of literature pertaining to Bartter's and PseudoBartter's syndromes. RESULTS: Purging behaviors commonly result in a state of profound dehydration and chloride depletion that leads to the metabolic abnormalities characteristic of inheritable sodium and chloride renal tubular transport disorders. In the eating disorder patient, these abnormalities lead to a propensity towards marked edema formation. DISCUSSION: The metabolic and clinical manifestations of PseudoBartter's syndrome are seen more commonly than previously thought. It is important to appreciate that a complex self-perpetuating pathophysiology leads to the hypokalemic metabolic alkalosis characteristic of PseudoBartter syndrome. The metabolic abnormalities characteristic of this phenomenon should therefore be viewed in this context and the resulting predilection towards marked edema formation should be borne in mind.

Polydipsia and hyponatremia in a woman with anorexia nervosa.

OBJECTIVE: Hyponatremia is infrequently reported in the constellation of metabolic abnormalities in patients with eating disorders. We sought to identify the etiology and describe the management of a patient with anorexia nervosa and hyponatremia. METHOD: We report the case of a 23-year-old woman with anorexia nervosa who suffered with severe hyponatremia. RESULTS: The etiology of hyponatremia in this case, as in most patients with eating disorders, was multifactorial, encompassing both hypovolemic and euvolemic categories of hyponatremia. Multiple impairments in the ability to clear free water are responsible for a heightened risk for hyponatremia in patients with anorexia nervosa. DISCUSSION: This case underscores the importance of careful scrutiny of fluid intake, an awareness of medications that lead to hyponatremia, and the need for regular monitoring of serum electrolytes, even in patients with anorexia nervosa, to allow for an early diagnosis and to assist in the formulation of an effective treatment and prevention strategy.

"Leaning" the process of venous thromboembolism prophylaxis.

BACKGROUND: Lean principles have been used at Denver Health Medical Center since 2005 to streamline nonclinical processes. Despite allocation of significant resources, particularly the expense of low molecular weight heparin (LMWH), to prophylaxis of venous thromboembolism (VTE), the incidence of postoperative VTE was significantly worse than national benchmarks. VTE risk factors were not consistently assessed, and the prescribing of prophylaxis varied widely. Lean was employed to standardize and implement risk assessment and evidence-based VTE prophylaxis for the institution. METHODS: In a rapid improvement event, a multidisciplinary group formulated an evidence-based risk assessment tool and clinical practice guideline for VTE prophylaxis, with plans for hospitalwide implementation and monitoring. RESULTS: The effects were immediate and improved steadily with feedback to clinicians. Within six months, compliance with the standard approached 100%. One year after implementation, the use of LMWH decreased more than 60% below baseline, and the use of sequential compression devices decreased by nearly 30%. With increased use of unfractionated heparin, the cost savings on VTE prophylaxis exceeded $15,000 per month, for a total of $425,000 since implementation. Moreover, the incidence of VTE decreased markedly during the same period. By reducing VTE rates, a total cost savings of $6.2 million was estimated for the past 28 months. CONCLUSIONS: Applying Lean to the clinical management of VTE prophylaxis improved compliance with standards and saved the hospital a significant amount of money. This was achieved without compromising clinical outcomes. This experience could be replicated at other institutions.

Aspiration thrombectomy and intracoronary tirofiban via GuideLiner® catheter for a thrombosed aneurysmal vessel.

A 52-year-old Asian male with no traditional risk factors for coronary artery disease presented with acute coronary syndrome. Coronary angiography showed complete thrombotic occlusion of the left circumflex with a large thrombus burden in the setting of diffuse aneurysmal enlargement of the coronary arteries consistent with antecedent Kawasaki disease. Manual thrombectomy with adjunctive intracoronary tirofiban was performed utilizing the GuideLiner catheter® (Vascular Solutions, Inc., MN, USA). Stent implantation was deferred. Follow-up imaging 48 h later showed preserved coronary flow and decreased thrombus burden. The GuideLiner catheter, a monorail guiding device, served a novel role in thrombus aspiration and intracoronary medication delivery.

Navigating complex femoropopliteal and infrapopliteal anatomy in endovascular interventions.

Peripheral arterial disease (PAD) is a clinical manifestation of systemic atherosclerosis and is associated with significant morbidity and mortality. Vascular physicians come across PAD of different complexity and among them complex total occlusions present a formidable challenge to endovascular operators. Newer tools and techniques, particularly in the retrograde approach, have made endovascular therapy applicable to increasingly complex disease. In this article, we review various interventional devices and techniques that are key to achieving success in complex anatomic subsets.

Effects of mineralocorticoid receptor antagonists on the risk of sudden cardiac death in patients with left ventricular systolic dysfunction: a meta-analysis of randomized controlled trials.

BACKGROUND: Sudden cardiac death (SCD) is an important cause of death in patients with left ventricular systolic dysfunction. Mineralocorticoid receptor antagonists (MRAs) may attenuate this risk. The objective of this meta-analysis was to assess the impact of MRAs on SCD in patients with left ventricular systolic dysfunction. METHODS AND RESULTS: We systematically searched PubMed, EMBASE, Cochrane, and other databases through March 30, 2012, without language restrictions. We included trials that enrolled patients with left ventricular ejection fraction of ≤45%, randomized subjects to MRAs versus control and reported outcomes on SCD, total and cardiovascular mortality. Eight published trials that enrolled 11 875 patients met inclusion criteria. Of these, 6 reported data on SCD and cardiovascular mortality, and 7 reported data on total mortality. No heterogeneity was observed among the trials. Patients treated with MRAs had 23% lower odds of experiencing SCD compared with controls (odds ratio, 0.77; 95% confidence interval, 0.66-0.89; P=0.001). Similar reductions were observed in cardiovascular (0.75; 95% confidence interval, 0.68-0.84; P<0.001) and total mortality (odds ratio, 0.74; 95% confidence interval, 0.63-0.86; P<0.001). Although publication bias was observed, the results did not change after a trim and fill test, suggesting that the impact of this bias was likely insignificant. CONCLUSIONS: MRAs reduce the risk of SCD in patients with left ventricular systolic dysfunction. Comparative effectiveness studies of MRAs on SCD in usual care as well as studies evaluating the efficacy of other therapies to prevent SCD in patients receiving optimal MRA therapy are needed to guide clinical decision-making.

The modified Wells score accurately excludes pulmonary embolus in hospitalized patients receiving heparin prophylaxis.

BACKGROUND: The usefulness of the Wells score has not been assessed in hospitalized patients receiving prophylactic heparin. METHODS: Retrospective, observational study of hospitalized patients receiving prophylactic heparin who underwent contrast-enhanced chest computed tomography (CT) for a concern of pulmonary embolism (PE) more than 2 days after admission. Patients with contraindications to, or interruptions in, prophylactic heparin were excluded. The modified (eg, dichotomous) Wells score was retrospectively calculated by reviewing each patient's record. Requesting a D-dimer was taken to mean that alternate diagnoses were of equal or greater likelihood than acute PE. RESULTS: From January 2006 through December 2007, 286 patients met inclusion criteria. Pulmonary embolus diagnosed by CT was present in 20 patients (7%). The sensitivity, specificity, positive and negative predictive values of a Wells score ≥4.0 were 95%, 27%, 9% and 99%, respectively. A D-dimer was ordered in 70 of the 74 PE-unlikely cases, was elevated in 67, and falsely positive in all but 1. CONCLUSIONS: The prevalence of PE in hospitalized patients receiving prophylactic heparin is lower than in cohorts from which the Wells prediction criteria were derived and validated. A modified Wells score <4 safely excludes PE in such patients and reduces the need for CT. D-dimer testing adds nothing to the evaluation.