We report a patient with hypoxia secondary to a right-to-left shunt through a patent foramen ovale, following aortic root, valve, and arch replacement due to an aortic dissection in the setting of the Marfan syndrome. Following the operation, he failed extubation twice due to hypoxia. An extensive workup revealed a right-to-left shunt previously not seen. The patent foramen ovale was closed using a percutaneous closure device. Following closure, our patient was extubated without difficulty and has done well postoperatively.A pproximately 25% of the general population is estimated to have a patent foramen ovale (PFO). Th ese small atrial septal defects, present from birth, are usually asymptomatic and found incidentally by echocardiogram or at autopsy (1). We describe the benefi t of closure of a PFO for postoperative hypoxia. CASE DESCRIPTIONA 23-year-old Hispanic man with the Marfan syndrome presented with acute chest pain that radiated to his back. Th e diagnosis of a dilated aortic root and a type B aortic dissection was made quickly by computed tomography scan with contrast. He underwent surgical repair using a two-staged "elephant trunk" procedure. Th e initial stage of the procedure consists of an aortic valve, root, and arch replacement, including leaving an elephant trunk portion of the graft that hangs down into the descending aorta. Finally the descending thoracic aorta is wrapped at that level of the diaphragm. Th e second stage of the procedure uses a stent graft, via an endovascular approach, to connect the elephant trunk with the wrapped portion of the aorta. Following the fi rst stage, his postoperative course was complicated by recurrent hypoxia. He underwent two attempted extubations on postoperative days 1 and 7, but the hypoxia persisted. A PFO with a signifi cant right-to-left shunt was found on transesophageal echocardiogram with bubble study (Figure 1).On postoperative day 9, a percutaneous closure procedure was performed via the right femoral vein. A #25 Amplatzer Cribriform Septal Occluder (AGA Medical Corp., Plymouth, MN) was deployed in the PFO, and placement was confi rmed with intracardiac echocardiography and fl uoroscopy (Figure 2). A negative echocardiographic bubble study at the conclusion of the procedure confi rmed resolution of the right-to-left shunt. On day 10, extubation was successful and normal oxygen saturation was maintained. Th e patient was discharged from the hospital on postoperative day 22. Five weeks later, he underwent stage 2 of the "elephant trunk" procedure without postoperative respiratory complications. He continues to do well 5 months following the second stage of the procedure. DISCUSSIONDespite the severity of potential consequences of a PFO, hypothesized benefi ts of closing PFOs, specifi cally for migraine headaches and strokes, have not resulted in clinical benefi t over standard medical management. Th ree large randomized controlled trials, RESPECT (2), CLOSURE I (3), and PC Trial (4), failed to show a benefi t of PFO closure over medical management fo...

Introduction: Biomarkers reported as being less than the limit of detection (LOD) are challenging to be included in analyses without being dichotomized. Substitutions by the LOD, LOD/2, LOD/√2, or zero have been attempted for left-censored values. We calculated a novel Modified Myocardial Injury Summary Score (MMISS) by incorporating four biomarkers (B-type natriuretic peptide, troponin, galectin-3, and suppression of tumorigenicity 2) to efficiently stratify heart failure (HF) patients. The objective of this study is to evaluate the differences in associations between MMISS, calculated by different methods of substitution, and therapeutic intensity index (TII), a composite pharmacologic score. Methods and results: This is a cross-sectional study including 39 HF patients aged ≥18 years who were treated in the Baylor Health Care System. MMISS was calculated with the left-censored biomarkers substituted by zero, LOD, LOD/2, and LOD/√2. Patients with biomarker values more than LOD (complete cases) were also considered separately. The computed TII was regressed separately on MMISS for each substitution method, while controlling for age and gender. All substitution methods yielded negative associations; however, statistical significance for the association was not achieved using substitution by zero or when considering only the complete cases. The association was quite comparable with the substitution of left-censored values by LOD, LOD/2, and LOD/√2. Conclusion: Substantial loss of information is inevitable if only the data with values above the LOD are considered for analysis or when the left-censored values are substituted with zero.

Introduction: The 2013 American College of Cardiology/American Heart Association postulated four blood biomarkers as key parameters in the risk-stratification and management of heart failure (HF). These four markers, troponin I or T, B-type natriuretic peptide or N-terminal BNP, galectin-3, and ST2, each reflect different aspects of myocardial pathophysiology in HF. We propose a novel method of integration of biomarkers which are summarized into a Modified Myocardial Injury Summary Score (MMISS) to serve as an individualized biomarker-based index of HF severity. Methods: For each patient, biomarkers were used to calculate the MMISS (Σ log10 [Biomarker(i)measured / Biomarker(i)ULN]/n, i=1). Pharmacologic regimen recorded at the time of biomarker draw was assimilated into a Therapeutic Intensity Index (TTI) based upon dosing of pertinent HF drug classes. A univariate analysis was performed to determine the relationship between MMISS and TII among patients included in this cross sectional study. Results: Of the 39 patients included in the study, 61.9% were male with a mean age of 60.5 ± 10.5. A total of 13(33.3%), 22(56.4%), and 4(10.3%) patients were classified as NYHA FC 2, 3, and 4, respectively. The etiology of HF was ischemic cardiomyopathy in 51% of patients. In creating the MMISS, 24(61.5%), 2(5.1%), and 13(33.3%) patients had two, three, and four biomarkers available, respectively. Through our analysis, we found the MMISS (range -0.76 to +1.08) to have no association with TII (R= -0.23, p=0.15). Conclusions: There is no significant correlation between the intensity of medical management and myocardial disease severity as reflected by cardiac biomarkers measured at a single time in cross-section. Our findings suggest there may be an opportunity to tailor therapy to the severity of disease as indicated by blood biomarkers. We plan to use our observation as basis for a randomized trial that leverages measured changes in MMISS to guide personalization of medical therapy.