Applying computable phenotypes within a common data model to identify heart failure patients for an implantable cardiac device registry.

BACKGROUND: Use of existing data in electronic health records (EHRs) could be used more extensively to better leverage real world data for clinical studies, but only if standard, reliable processes are developed. Numerous computable phenotypes have been validated against manual chart review, and common data models (CDMs) exist to aid implementation of such phenotypes across platforms and sites. Our objective was to measure consistency between data that had previously been manually collected for an implantable cardiac device registry and CDM-based phenotypes for the condition of heart failure (HF). METHODS: Patients enrolled in an implantable cardiac device registry at two hospitals from 2013 to 2018 contributed to this analysis wherein registry data were compared to PCORnet CDM-formatted EHR data. Seven different phenotype algorithms were used to search for the presence of HF and compare the results with the registry. Sensitivity, specificity, predictive value and congruence were calculated for each phenotype. RESULTS: In the registry, 176 of 319 (55%) patients had history of HF, compared with different phenotypes estimating between 96 (30%) and 188 (59%). The least-restrictive phenotypes (any diagnosis) had high sensitivity and specificity (90%/80%), but more restrictive phenotypes had higher specificity (e.g., code present in problem list, 94%). Differences were observed using time-based criteria (e.g., days between visit diagnoses) and between participating hospitals. CONCLUSIONS: Consistency between manually-collected registry data and CDM-based phenotypes for history of HF was high overall, but use of different phenotypes impacted sensitivity and specificity, and results may differ depending on the medical condition of interest.

Totally Implantable IV Treprostinil Therapy in Pulmonary Hypertension Assessment of the Implantation Procedure.

BACKGROUND: Prostacyclins improve symptoms and survival in pulmonary arterial hypertension (PAH). In response to risks associated with external delivery systems, an implantable IV infusion system was developed. A multicenter, prospective, single-arm, clinical trial (DelIVery for PAH) was conducted to evaluate this system for treprostinil in PAH. This analysis describes the findings related to the implant procedure. METHODS: Patients (N = 64) with PAH (World Health Organization group 1) receiving stable IV treprostinil were enrolled. Patients were transitioned to a temporary peripheral IV infusion catheter prior to the procedure. System implantation was performed at 10 centers under general anesthesia or deep IV sedation by clinicians from various specialties. Central venous access was via the cephalic, subclavian, jugular, or axillary vein. Using an introducer and fluoroscopic guidance, the distal tip of the infusion catheter was placed at the superior caval-atrial junction. The catheter was tunneled from the venous access site to an abdominal subcutaneous pocket, where the pump was placed. RESULTS: Of the 64 patients enrolled, four exited prior to implantation. All 60 implant procedures were successful. At baseline, all patients were receiving treprostinil via an external pump at a mean dose of 71.4 ± 27.8 ng/kg/min (range: 22-142 ng/kg/min). The implant averaged 102 ± 32 min (range: 47-184 min). Clinically significant implant procedure-related complications included one pneumothorax, two infections, and one episode of atrial fibrillation. There were three postimplantation catheter dislocations in two patients. Common implant-related events that were not complications included implant site pain (83%) and bruising (17%). CONCLUSIONS: The procedure for inserting a fully implantable system for treprostinil was successfully performed, with few complications. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01321073; URL: www.clinicaltrials.gov.

Weight loss alone improves conduit and resistance artery endothelial function in young and older overweight/obese adults.

Obesity is associated with vascular endothelial dysfunction, as indicated by impaired endothelium-dependent dilation. Presently there is no direct evidence that energy intake-restricted weight loss alone improves conduit or resistance artery endothelium-dependent dilation, the mechanisms involved, or whether improvements differ with patient age. A total of 40 overweight or obese (body mass index: >or=25<40 kg/m(2)) nondiabetic men and women aged 21 to 69 years completed 12 weeks of reduced energy intake (n=26; 15 male) or attention control (n=14; 9 male) and 4 weeks of weight maintenance (randomized trial). Energy intake restriction reduced estimated total energy intake (33%), body weight (10.5%), total and abdominal body fat, plasma leptin, oxidized low-density lipoprotein, and improved several metabolic risk factors. Brachial artery flow-mediated dilation was increased by 30% (6.0+/-0.7% versus 7.9+/-0.7%Delta; P=0.01; n=17). Peak forearm blood flow during intrabrachial artery infusion of acetylcholine was increased by 26% (16.8+/-1.4 versus 21.1+/-1.9 mL/100 mL per minute; P<0.05; n=15); this was inversely related to the reduction in the abdominal visceral:subcutaneous fat ratio (r=-0.46; P<0.05) and was abolished by inhibition of NO synthesis with N(G)-monomethyl-L-arginine. Improvements in endothelium-dependent dilation were not related to age: mean increases in subjects >50 years of age were similar to or greater than those <50 years of age. Energy intake-restricted weight loss alone is an effective intervention for improving peripheral conduit and resistance artery endothelial function in young and older overweight/obese adults. The improvements in resistance artery function are mediated by an increase in NO bioavailability and are related to reductions in abdominal visceral fat.