Rickey E. Carter

Background: Diagnosis of heart failure with preserved ejection fraction (HFpEF) is challenging in euvolemic patients with dyspnea, and no evidence-based criteria are available. We sought to develop and then validate noninvasive diagnostic criteria that could be used to estimate the likelihood that HFpEF is present among patients with unexplained dyspnea to guide further testing. Methods: Consecutive patients with unexplained dyspnea referred for invasive hemodynamic exercise testing were retrospectively evaluated. Diagnosis of HFpEF (case) or noncardiac dyspnea (control) was ascertained by invasive hemodynamic exercise testing. Logistic regression was performed to evaluate the ability of clinical findings to discriminate cases from controls. A scoring system was developed and then validated in a separate test cohort. Results: The derivation cohort included 414 consecutive patients (267 cases with HFpEF and 147 controls; HFpEF prevalence, 64%). The test cohort included 100 consecutive patients (61 with HFpEF; prevalence, 61%). Obesity, atrial fibrillation, age >60 years, treatment with ≥2 antihypertensives, echocardiographic E/e’ ratio >9, and echocardiographic pulmonary artery systolic pressure >35 mm Hg were selected as the final set of predictive variables. A weighted score based on these 6 variables was used to create a composite score (H 2 FPEF score) ranging from 0 to 9. The odds of HFpEF doubled for each 1-unit score increase (odds ratio, 1.98; 95% CI, 1.74–2.30; P <0.0001), with an area under the curve of 0.841 ( P <0.0001). The H 2 FPEF score was superior to a currently used algorithm based on expert consensus (increase in area under the curve of 0.169; 95% CI, 0.120–0.217; P <0.0001). Performance in the independent test cohort was maintained (area under the curve, 0.886; P <0.0001). Conclusions: The H 2 FPEF score, which relies on simple clinical characteristics and echocardiography, enables discrimination of HFpEF from noncardiac causes of dyspnea and can assist in determination of the need for further diagnostic testing in the evaluation of patients with unexplained exertional dyspnea.

This Consensus Document is the first of two reports summarizing the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) on the clinical use of intracoronary imaging including intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The first document appraises the role of intracoronary imaging to guide percutaneous coronary interventions (PCIs) in clinical practice. Current evidence regarding the impact of intracoronary imaging guidance on cardiovascular outcomes is summarized, and patients or lesions most likely to derive clinical benefit from an imaging-guided intervention are identified. The relevance of the use of IVUS or OCT prior to PCI for optimizing stent sizing (stent length and diameter) and planning the procedural strategy is discussed. Regarding post-implantation imaging, the consensus group recommends key parameters that characterize an optimal PCI result and provides cut-offs to guide corrective measures and optimize the stenting result. Moreover, routine performance of intracoronary imaging in patients with stent failure (restenosis or stent thrombosis) is recommended. Finally, strengths and limitations of IVUS and OCT for guiding PCI and assessing stent failures and areas that warrant further research are critically discussed.

Advances in clinical and translation science are facilitated by building on prior knowledge gained through experimentation and observation. In the context of drug development, preclinical studies are followed by a progression of phase I through phase IV clinical trials. At each step, the study design and statistical strategies are framed around research questions that are prerequisites for the next phase. In other types of biomedical research, pilot studies are used for gathering preliminary support for the next research step. However, the phrase "pilot study" is liberally applied to projects with little or no funding, characteristic of studies with poorly developed research proposals, and usually conducted with no detailed thought of the subsequent study. In this article, we present a rigorous definition of a pilot study, offer recommendations for the design, analysis and sample size justification of pilot studies in clinical and translational research, and emphasize the important role that well-designed pilot studies play in the advancement of science and scientific careers.