Guidelines and principles for the care of the cardiothoracic transplant patient in the intensive care unit.

Heart and lung transplant recipients require care provided by clinicians from multiple different specialties, each contributing unique expertise and perspective. The period the patient spends in the intensive care unit is one of the most critical times in the perioperative trajectory. Various organizational models of intensive care exist, including those led by intensivists, surgeons, transplant cardiologists, and pulmonologists. Coordinating timely efficient intensive care is an essential and logistically difficult goal. The present work product of the American Society of Transplantation's Thoracic and Critical Care Community of Practice, Critical Care Task Force outlines operational guidelines and principles that may be applied in different organizational models to optimize the delivery of intensive care for the cardiothoracic organ recipient.

White paper on antimicrobial stewardship in solid organ transplant recipients.

Antimicrobial stewardship programs (ASPs) have made immense strides in optimizing antibiotic, antifungal, and antiviral use in clinical settings. However, although ASPs are required institutionally by regulatory agencies in the United States and Canada, they are not mandated for transplant centers or programs specifically. Despite the fact that solid organ transplant recipients in particular are at increased risk of infections from multidrug-resistant organisms, due to host and donor factors and immunosuppressive therapy, there currently are little rigorous data regarding stewardship practices in solid organ transplant populations, and thus, no transplant-specific requirements currently exist. Further complicating matters, transplant patients have a wide range of variability regarding their susceptibility to infection, as factors such as surgery of transplant, intensity of immunosuppression, and presence of drains or catheters in situ may modify the risk of infection. As such, it is not feasible to have a "one-size-fits-all" style of stewardship for this patient population. The objective of this white paper is to identify opportunities, risk factors, and ASP strategies that should be assessed with solid organ transplant recipients to optimize antimicrobial use, while producing an overall improvement in patient outcomes. We hope it may serve as a springboard for development of future guidance and identification of research opportunities.

Symptomatic Respiratory Virus Infection and Chronic Lung Allograft Dysfunction.

BACKGROUND: Chronic lung allograft dysfunction (CLAD) is a major cause of allograft loss post-lung transplantation. Prior studies have examined the association between respiratory virus infection (RVI) and CLAD were limited by older diagnostic techniques, study design, and case numbers. We examined the association between symptomatic RVI and CLAD using modern diagnostic techniques in a large contemporary cohort of lung transplant recipients (LTRs). METHODS: We retrospectively assessed clinical variables including acute rejection, cytomegalovirus pneumonia, upper and lower RVI, and the primary endpoint of CLAD (determined by 2 independent reviewers) in 250 LTRs in a single university transplantation program. Univariate and multivariate Cox models were used to analyze the relationship between RVI and CLAD in a time-dependent manner, incorporating different periods of risk following RVI diagnosis. RESULTS: Fifty patients (20%) were diagnosed with CLAD at a median of 95 weeks post-transplantation, and 79 (32%) had 114 episodes of RVI. In multivariate analysis, rejection and RVI were independently associated with CLAD (adjusted hazard ratio [95% confidence interval]) 2.2 (1.2-3.9), P = .01 and 1.9 (1.1-3.5), P = .03, respectively. The association of RVI with CLAD was stronger the more proximate the RVI episode: 4.8 (1.9-11.6), P < .01; 3.4 (1.5-7.5), P < .01; and 2.4 (1.2-5.0), P = .02 in multivariate analysis for 3, 6, and 12 months following RVI, respectively. CONCLUSIONS: Symptomatic RVI is independently associated with development of CLAD, with increased risk at shorter time periods following RVI. Prospective studies to characterize the virologic determinants of CLAD and define the underlying mechanisms are warranted.

Outcomes of lung transplantation after allogeneic hematopoietic stem cell transplantation.

Other than lung transplantation (LT), no specific therapies exist for end-stage lung disease resulting from hematopoietic stem cell transplantation (HCT)-related complications, such as bronchiolitis obliterans syndrome (BOS). We report the indications and outcomes in patients who underwent LT after HCT for hematologic disease from a retrospective case series at our institution and a review of the medical literature. We identified a total of 70 cases of LT after HCT, including 9 allogeneic HCT recipients from our institution who underwent LT between 1990 and 2010. In our cohort, the median age was 16 years (range, 10 to 35 years) at the time of HCT and 34 years (range, 17 to 44 years) at the time of LT, with a median interval between HCT and LT of 10 years (range, 2.9 to 27 years). Indications for LT-included pulmonary fibrosis (n = 4), BOS (n = 3), interstitial pneumonitis related to graft-versus-host disease (GVHD) (n = 1), and primary pulmonary hypertension (n = 1). Median survival was 49 months (range, 2 weeks to 87 months), and 1 patient remains alive at more than 3 years after LT. Survival at 1 year and 5 years after LT was 89% and 37%, respectively. In the medical literature between 1992 and July 2013, we identified 20 articles describing 61 cases of LT after HCT from various centers in the United States, Europe, and Asia. Twenty-six of the 61 cases (43%) involved patients age <18 years at the time of LT. BOS and GVHD of the lung were cited as the indication for LT in the majority of cases (80%; n = 49), followed by pulmonary fibrosis and interstitial lung disease (20%; n = 12). In publications reporting 3 or more cases with a follow-up interval ranging from the immediate postoperative period to 16 years, the survival rate was 71% (39 of 55). Most deaths were attributed to long-term complications of the lung allograft, including infections and BOS. Two deaths were related to recurrent or relapsed hematologic malignancy. LT can prolong survival in some patients who suffer from end-stage pulmonary complications after HCT. Patient factors that likely improve the chances of a good long-term outcome include young age, at least 2 years post-HCT free of relapse from the original hematologic malignancy, and lack of other end-organ dysfunction or manifestations of chronic GVHD that require treatment with immunosuppressive agents.

Comparative evaluation of miRNA expression between in vitro and in vivo airway epithelium demonstrates widespread differences.

Airway epithelial cells cultured at an air-liquid interface bear many hallmarks of in vivo cells and are used extensively to study the biology of the lung epithelium. Because miRNAs regulate many cellular functions, we postulated that miRNA profiling would provide an unbiased assessment of the effects of in vitro culturing. RNA was extracted from primary airway epithelial cells either immediately after cell procurement (in vivo condition) or after air-liquid interface culture was established (in vitro condition). We assessed 742 miRNAs and determined differential expression between in vivo and in vitro conditions. Air-liquid interface culturing of airway epithelial cells caused widespread changes in miRNA expression. A similarly extensive alteration in gene expression was observed in an independent set of publicly available microarray data. We integrated miRNA and gene expression results to identify culture-induced differences in transcriptional programs (including several involved in epithelial injury and repair). Air-liquid interface cultures are useful models for studying airway biology, but the present findings indicate that, despite phenotypic similarities with primary cells, these culture systems profoundly perturb miRNA and gene expression. Studies of lung epithelium based on in vitro culture should therefore be designed and interpreted with an appreciation of the limitations of air-liquid interface culture systems.

Cognitive and Emotional Responses to Chronic Obstructive Pulmonary Disease Exacerbations and Patterns of Care Seeking.

Rationale: Cognitive and emotional responses associated with care seeking for chronic obstructive pulmonary disease (COPD) exacerbations are not well understood.Objectives: We sought to define care-seeking profiles based on whether and when U.S. veterans seek care for COPD exacerbations and compare cognitive and emotional responses with exacerbation symptoms across the profiles.Methods: This study analyzes data from a 1-year prospective observational cohort study of individuals with COPD. Cognitive and emotional responses to worsening symptoms were measured with the Response to Symptoms Questionnaire, adapted for COPD. Seeking care was defined as contacting or visiting a healthcare provider or going to the emergency department. Participants were categorized into four care-seeking profiles based on the greatest delay in care seeking for exacerbations when care was sought: 0-3 days (early), 4-7 days (short delay), >7 days (long delay), or never sought care for any exacerbation. The proportion of exacerbations for which participants reported cognitive and emotional responses was estimated for each care-seeking profile, stratified by the timing of when care was sought.Results: There were 1,052 exacerbations among 350 participants with Response to Symptoms Questionnaire responses. Participants were predominantly male (96%), and the mean age was 69.3 ± 7.2 years. For the 409 (39%) exacerbations for which care was sought, the median delay was 3 days. Those who sought care had significantly more severe COPD (forced expiratory volume in 1 s, modified Medical Research Council dyspnea scale) than those who never sought care. Regardless of the degree of delay until seeking care at one exacerbation, participants consistently reported experiencing serious symptoms if they sought care compared with events for which participants did not seek care (e.g., among early care seekers when care was sought, 36%; when care was not sought, 25%). Similar findings were seen in participants' assessment of the importance of getting care (e.g., among early care seekers when care was sought, 90%; when care was not sought, 52%) and their assessment of anxiety about the symptoms (e.g., among early care seekers when care was sought, 33%; when care was not sought, 17%).Conclusions: Delaying or not seeking care for COPD exacerbations was common. Regardless of care-seeking profile, cognitive and emotional responses to symptoms when care was sought differed from responses when care was not sought. Emotional and cognitive response to COPD exacerbations should be considered when developing individualized strategies to encourage seeking care for exacerbations.Clinical trial registered with www.clinicaltrials.gov (NCT02725294).

Teduglutide enhances structural adaptation of the small intestinal mucosa in patients with short bowel syndrome.

BACKGROUND: Intestinotrophic therapies, such as glucagon-like peptide-2 (GLP-2) analogs, may enhance intestinal adaptation and reduce dependence on parenteral nutrition (PN) in patients with intestinal failure associated with short bowel syndrome (SBS-IF). However, because GLP-2 enhances cellular growth, there is concern that GLP-2 analogs may also encourage growth of malignant cells. AIMS: To histologically examine the effects of teduglutide, a recombinant human GLP-2 analog, on the mucosa of the small and large intestine for indications of dysplastic transformation. METHODS: In a multicenter, prospective, randomized, placebo-controlled study, 83 PN-dependent patients with SBS-IF were monitored for several weeks to ensure optimal and stable PN. Patients were then randomized to receive 24 weeks of placebo (n=16), teduglutide (0.5 mg/kg/d; n=35), or teduglutide (0.10 mg/kg/d; n=32). RESULTS: Biopsies were obtained from 77 patients to yield 390 individual histologic interpretations. After 6 months of treatment, no features of dysplasia were found in any biopsy from the large or small intestine of patients receiving placebo or either dose of teduglutide. New secondary diagnoses, such as eosinophilic colitis or Crohn's disease, were found at a low frequency overall: teduglutide (0.05 mg/kg/d; range, 3.1% to 6.3%); teduglutide (0.10 mg/kg/d, 3.3%); placebo (range, 6.7% to 13.3%). CONCLUSIONS: Although this histologic substudy of biopsy samples was not powered to detect differences in occurrence of dysplasia between teduglutide-treated patients and those randomized to placebo, it demonstrated that no dysplasia or other pathologic processes were evident within the intestinal mucosa in the placebo group or the 2 teduglutide groups after 6 months of treatment.

Survivin Dendritic Cell Vaccine Safely Induces Immune Responses and Is Associated with Durable Disease Control after Autologous Transplant in Patients with Myeloma.

PURPOSE: We investigated whether a dendritic cell (DC) vaccine transduced with an adenoviral vector encoded with full-length survivin (Ad-S), with mutations neutralizing its antiapoptotic function, could safely generate an immune response and deepen clinical responses when administered before and after autologous stem cell transplant (ASCT) for multiple myeloma. PATIENTS AND METHODS: This phase I first-in-human trial (NCT02851056) evaluated the safety of DC:Ad-S in newly diagnosed multiple myeloma not having achieved complete response with induction, given 7 to 30 days prior to stem cell collection and 20 to 34 days after ASCT. Anti-survivin antibodies and CD4+ and CD8+ specific T cells were quantified. RESULTS: A total of 14 patients were treated and 13 included in the primary efficacy analysis. No serious adverse events were attributed to DC:Ad-S vaccine. Detectable anti-survivin antibodies increased from baseline in 9 of 13 (69%) patients, and 11 of 13 (85%) mounted either a cellular or humoral immune response to survivin. Seven patients had an improved clinical response at day +90, all of whom had mounted an immune response, and 6 of 7 patients remain event-free at a median follow-up of 4.2 years. Estimated progression-free survival at 4 years is 71% (95% confidence interval, 41-88). CONCLUSIONS: Two doses of DC:Ad-S, one given immediately before and another after ASCT, were feasible and safe. A high frequency of vaccine-specific immune responses was seen in combination with durable clinical outcomes, supporting ongoing investigation into the potential of this approach. See related commentary by Dhodapkar, p. 4524.

Involvement of tristetraprolin in transcriptional activation of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase by insulin.

Several AU-rich RNA binding element (ARE) proteins were investigated for their possible effects on transcription of hepatic 3-hydroxy-3-methyglutaryl coenzyme A reductase (HMGR) in normal rats. Using in vivo electroporation, four different siRNAs to each ARE protein were introduced together with HMGR promoter (-325 to +20) luciferase construct and compared to saline controls. All four siRNAs to tristetraprolin (TTP) completely eliminated transcription from the HMGR promoter construct. Since insulin acts to rapidly increase hepatic HMGR transcription, the effect of TTP siRNA on induction by insulin was tested. The 3-fold stimulation by insulin was eliminated by this treatment. In comparison, siRNA to AU RNA binding protein/enoyl coenzyme A hydratase (AUH) had no effect. These findings indicate a role for TTP in the insulin-mediated activation of hepatic HMGR transcription.

Care-seeking and delay of care during COPD exacerbations.

Patients who receive earlier treatment for acute exacerbations of chronic obstructive pulmonary disease (COPD) have a better prognosis, including earlier symptom resolution and reduced risk of future emergency-department visits (ED) or hospitalizations. However, many patients delay seeking care or do not report worsening symptoms to their healthcare provider. In this study, we aimed to understand how patients perceived their breathing symptoms and identify factors that led to seeking or delaying care for an acute exacerbation of COPD. We conducted semistructured interviews with 60 individuals following a recent COPD exacerbation. Participants were identified from a larger study of outpatients with COPD by purposive sampling by exacerbation type: 15 untreated, 15 treated with prednisone and/or antibiotics in the outpatient setting, 16 treated in an urgent care or ED setting, and 14 hospitalized. Data were analyzed using inductive content analysis. Participants were primarily male (97%) with a mean age of 69.1 ± 6.9 years, mean FEV1 1.42 (±0.63), and mean mMRC dyspnea of 2.7 (±1.1). We identified 4 primary themes: (i) access and attitudinal barriers contribute to reluctance to seek care, (ii) waiting is a typical response to new exacerbations, (iii) transitioning from waiting to care-seeking: the tipping point, and (iv) learning from and avoiding worse outcomes. Interventions to encourage earlier care-seeking for COPD exacerbations should consider individuals' existing self-management approaches, address attitudinal barriers to seeking care, and consider health-system changes to increase access to non-emergent outpatient treatment for exacerbations.Clinical Trial Registration NCT02725294.

Polymer-free corticosteroid dimer implants for controlled and sustained drug delivery.

Polymeric drug carriers are widely used for providing temporal and/or spatial control of drug delivery, with corticosteroids being one class of drugs that have benefitted from their use for the treatment of inflammatory-mediated conditions. However, these polymer-based systems often have limited drug-loading capacity, suboptimal release kinetics, and/or promote adverse inflammatory responses. This manuscript investigates and describes a strategy for achieving controlled delivery of corticosteroids, based on a discovery that low molecular weight corticosteroid dimers can be processed into drug delivery implant materials using a broad range of established fabrication methods, without the use of polymers or excipients. These implants undergo surface erosion, achieving tightly controlled and reproducible drug release kinetics in vitro. As an example, when used as ocular implants in rats, a dexamethasone dimer implant is shown to effectively inhibit inflammation induced by lipopolysaccharide. In a rabbit model, dexamethasone dimer intravitreal implants demonstrate predictable pharmacokinetics and significantly extend drug release duration and efficacy (>6 months) compared to a leading commercial polymeric dexamethasone-releasing implant.

Differentiating intraocular glucocorticoids.

BACKGROUND: Natural corticosteroids (e.g. hydrocortisone) and synthetic selective glucocorticoid (GC) agonists have been used by ophthalmologists for decades to treat various forms of ocular inflammation. More recently, increased clinical use of locally delivered GC has shown significant benefit for the treatment of multiple retinal indications including macular edema associated with uveitis, retinal vascular occlusions and diabetes. Our current understanding of the clinical utility of specific intraocular GC far surpasses our knowledge of their biologic and pharmacologic activities in the eye. OBJECTIVE: To present an update on GC receptor (GR) biology in general and as it applies to the eye, and discuss the pharmacokinetics, delivery and pharmacology of the commonly used intraocular GC dexamethasone (DEX), triamcinolone acetonide (TA) and fluocinolone acetonide (FA). RESULTS: DEX, TA and FA are structurally similar but significantly differentiated by their aqueous and lipid solubility, delivery system requirements, pharmacokinetics and interactions with functional GR. Culture of human trabecular meshwork cells and full transcriptome microarray analysis reveals that DEX, TA and FA generate unique gene transactivation and repression profiles as well as potentially distinct biologic responses that are not only steroid structure dependent, but also dose and time dependent. Finally, DEX and FA markedly protect photoreceptors from degenerating in animal models of excessive light and retinitis pigmentosa, respectively. CONCLUSION: It is tempting to speculate that the unique pharmacokinetic and pharmacologic profiles of the commonly used intraocular steroids and novel future drugs may reveal significant differences in their therapeutic value in patients with macular edema or other inflammatory disease, in their ocular adverse side effect profile, and their ability to normalize glial and neuronal function in diseased retina.

International Society for Heart and Lung Transplantation consensus statement for the standardization of bronchoalveolar lavage in lung transplantation.

Bronchoalveolar lavage (BAL) is a key clinical and research tool in lung transplantation (LTx). However, BAL collection and processing are not standardized across LTx centers. This International Society for Heart and Lung Transplantation-supported consensus document on BAL standardization aims to clarify definitions and propose common approaches to improve clinical and research practice standards. The following 9 areas are covered: (1) bronchoscopy procedure and BAL collection, (2) sample handling, (3) sample processing for microbiology, (4) cytology, (5) research, (6) microbiome, (7) sample inventory/tracking, (8) donor bronchoscopy, and (9) pediatric considerations. This consensus document aims to harmonize clinical and research practices for BAL collection and processing in LTx. The overarching goal is to enhance standardization and multicenter collaboration within the international LTx community and enable improvement and development of new BAL-based diagnostics.

Dexamethasone inhibits high glucose-, TNF-alpha-, and IL-1beta-induced secretion of inflammatory and angiogenic mediators from retinal microvascular pericytes.

PURPOSE: To characterize the effects of dexamethasone in human retinal pericytes (HRMPs), monocytes (THP-1), and retinal endothelial cells (HRECs) treated with high glucose, TNF-alpha, or IL-1beta. METHODS: HRMP and HREC phenotypes were verified by growth factor stimulation of intracellular calcium-ion mobilization. Glucocorticoid receptor phosphorylation was assessed with an anti-phospho-Ser(211) glucocorticoid receptor antibody. Secretion of 89 inflammatory and angiogenic proteins were compared in cells incubated with (1) normal (5 mM) or high (25 mM) D-glucose and (2) control medium, TNF-alpha (10 ng/mL), or IL-1beta (10 ng/mL), with or without dexamethasone (1 nM to 1 microM). The proteins were compared by using multianalyte profile testing. RESULTS: HRMPs and HRECs expressed functional PDGFB-R and VEGFR-2, respectively. Dexamethasone induction of glucocorticoid receptor phosphorylation was dose-dependent in all cell types. High glucose increased secretion of inflammatory mediators in HRMPs, but not in HRECs. Dexamethasone dose dependently inhibited secretion of these mediators in HRMPs. For all cells, TNF-alpha and IL-1beta induced a fivefold or more increase in inflammatory and angiogenic mediators; HRMPs secreted the greatest number and level of mediators. Dexamethasone dose dependently inhibited the secretion of multiple proteins from HRMPs and THP-1 cells, but not from HRECs (IC(50) 2 nM to 1 microM). CONCLUSIONS: High glucose, TNF-alpha, and IL-1beta induced an inflammatory phenotype in HRMPs, characterized by hypersecretion of inflammatory and angiogenic mediators. Dexamethasone at various potencies blocked hypersecretion of several proteins. Pericytes may be a key therapeutic target in retinal inflammatory diseases, including diabetic retinopathy. Inhibition of pathologic mediators may depend on delivering high levels ( approximately 1 microM) of glucocorticoid to the retina.

Intravitreal steroids for macular edema: the past, the present, and the future.

Macular edema, a condition usually associated with an underlying disease process, is a common cause of severe visual loss. There have been a variety of approaches to the treatment of macular edema; within the past few years, however, intravitreal corticosteroid treatments have emerged as an increasingly used treatment option for patients with macular edema. Intravitreal delivery allows the steroid to bypass the blood-retinal barrier, leading to a more concentrated dose of steroid for a prolonged period of time. Corticosteroids have likely been successful in the treatment of various forms of macular edema, due to their known anti-angiogenic, anti-edematous, anti-inflammatory, anti-apoptotic, and anti-proliferative effects. Intravitreal triamcinolone acetonide has been repeatedly successful in reducing macular edema and improving visual acuity, although the duration of action is typically short-term. Due to the recurrent and chronic nature of macular edema, biodegradable implants may be the future of intravitreal steroids. Intravitreal corticosteroids are not without risks. Steroid-related side effects include cataract formation and elevated intraocular pressure. Injection-related side effects include retinal detachment, vitreous hemorrhage, bacterial endophthalmitis, and sterile endophthalmitis. This article reviews the evolving role of intravitreal corticosteroids in the treatment of macular edema secondary to uveitis, diabetes, and retinal vascular disorders.

Lung allocation score for lung transplantation: impact on disease severity and survival.

BACKGROUND: Prior to implementation of the lung allocation score (LAS) system, allocation of donor lungs was based on accrued time on the waiting list and was potentially influenced by center-specific thresholds for listing. The impact of LAS implementation on patient characteristics and survival is unknown. METHODS: United Network of Organ Sharing data were obtained on all lung transplant candidates listed and all patients undergoing transplantation in region 6 between May 4, 2003, and May 4, 2006. Each data set was divided into two cohorts: 2 years before LAS implementation, and 1 year after LAS implementation. LAS was calculated and compared by cohort. Pre-LAS and post-LAS differences in patient characteristics were examined. Waiting list and posttransplant survival rates for each cohort were examined using Kaplan-Meier estimates and Cox regression. RESULTS: After LAS implementation, the distribution of diagnoses in patients undergoing transplantation significantly changed (p = 0.02), while the distribution of diagnoses in those listed did not (p = 0.17). Characteristics of patients on the waiting list were similar, except that a higher proportion of nonwhite patients were listed (p = 0.04) and lower FVC (p < 0.001) was observed after LAS implementation. Similarly, characteristics of patients undergoing transplantation did not change, except that posttransplant hospital length of stay was shorter (p = 0.01) after LAS implementation. Calculated LAS was higher after LAS implementation (p = 0.006). After controlling for age and diagnosis, neither waiting list nor transplant survival was significantly different (p = 0.93 and p = 0.81, respectively). CONCLUSIONS: After LAS implementation, the distribution of diagnoses in lung transplant recipients was significantly changed, while that of candidates was not. Posttransplant and waiting list survival were not affected by the LAS system, but power was limited. Larger and long-term survival studies are needed to determine if the LAS system improves overall allocation and survival for patients interested in lung transplantation.

Prostanoid therapy for pulmonary arterial hypertension.

Epoprostenol and the structurally related compounds treprostinil, iloprost, and beraprost are collectively referred to as prostanoids. The discovery of epoprostenol in 1976 and unequivocal demonstration of its efficacy in 1996 dramatically altered the approach to therapy for pulmonary arterial hypertension (PAH). Development of prostanoids available through multiple routes of administration and the discovery and development of other agents acting through alternative pathways continue to expand the array of therapeutic options. The use of prostanoids in combination with other PAH drugs and for treating pulmonary hypertensive disorders outside of the PAH classification are areas of ongoing research.

Clinical presentation, differential diagnosis, and vasodilator testing of pulmonary hypertension.

Clinicians should be cognizant of the symptoms and risk factors associated with pulmonary hypertension (PH). While known PH poses significant therapeutic challenges, occult PH carries the added potential for unanticipated complications when treating concurrent medical illnesses. PH may occur with underlying medical conditions and risk factors or may occur de novo as idiopathic pulmonary arterial hypertension (IPAH). Symptoms of PH are frequently attributed to more common conditions, and their nonspecific nature and insidious onset may lead to delay in presentation, evaluation, and diagnosis. Initial symptoms are dyspnea, fatigue, chest pain, and palpitations. Lower extremity edema, presyncope, and syncope are symptoms of more advanced disease. Thorough evaluation of symptoms and identification of patients with risk factors for PH are critical in making a timely diagnosis. History and physical examination can identify patients with suspected PH. Further testing is necessary for definitive diagnosis, classification, assessment of severity, and guiding therapeutic decisions.