Pereira, Naveen L.

Introduction: Phenome-wide association studies (PheWAS) using electronic medical record (EMR)-linked biobanks have been used not only to identify and replicate known associations of genetic variants with disease phenotypes but have also resulted in the discovery of potentially novel genotype-phenotype relationships. The natriuretic peptide (NP) system plays an important role in a broad range of disease processes including cardiovascular and inflammatory diseases. We hypothesized that performing a PheWAS using previously known functional genetic variants of the NP system may result in novel disease associations that could provide mechanistic insights in an unbiased manner. Methods: We scanned for associations between 9 single-nucleotide polymorphisms (SNPs) in the NP system and 27 EMR-derived chronic disease phenotypes in 3,025 individuals participating in a case-control study of peripheral arterial disease. The EMR phenotypes were identified using two or more ICD-9-CM diagnosis codes based on the AHRQ Clinical Classifications Software (CCS). The relationship of SNPs and phenotypes were modeled using logistic regression adjusting for gender. Results: We identified rs5065, a SNP located in the stop codon of exon 3 of the NPPA gene, to be the strongest associated SNP with rheumatoid arthritis (RA) (OR=0.78, p=0.0008, q-value=0.11). The SNP leads to the extension of atrial natriuretic peptide (ANP) by 2 additional arginines at the C terminus. Cardiovascular disease is known to be the leading cause of death in patients with RA and ANP plays an important immunomodulatory role by inhibiting inducible nitric oxide synthase, reducing TNF-α production and attenuating prostaglandin E2 production in macrophages. Circulating NPs have been used to screen for occult cardiac disease and are associated with mortality in RA. This study demonstrates for the first time the importance of the relationship between genetic variation in the NP system and RA. Conclusions: PheWAS was successfully used as a tool to identify a novel association of functional genetic variation in the NPPA gene with RA. The observation is hypothesis generating and further replication studies are required to determine the role of rs5065 in cardiovascular outcomes of RA.

Background: Galectin-3 (Gal-3) may promote cardiac and renal fibrosis in heart failure (HF). Plasma Gal-3 levels predict outcome in HF but are tightly correlated with renal function. The source of Gal-3 in human HF, chronic kidney disease (CKD) or cardio-renal failure (HF+CKD) is unclear. Objective: To assess Gal-3 presence and location in human heart or kidney tissue from patients with HF, CKD or HF+CKD. Methods: Plasma Gal-3 levels and LV tissue explanted at time of cardiac transplant in systolic HF (n=15) and autopsy renal sections from patients with normal kidneys (n=4), CKD (n=17) or CKD+HF (n=14) were examined (H&E, Masson’s trichrome and CD-68 and Gal-3 immunohistochemistry). In the systolic HF patients, we quantified the number of Gal-3+/CD-68+ cells per HPF in LV tissue and assessed the correlation with plasma Gal-3 levels. In autopsy renal tissue, we derived a Composite Gal-3 Score (CG3S) incorporating the % of Gal-3+ tubules per HPF, % of Gal-3+ cells/tubule per HPF, and intensity of Gal-3 staining and assessed the correlation of the CG3S with ante-mortem estimated glomerular filtration rate(eGFR). Renal macrophage Gal-3 staining was also assessed. Results: In systolic HF LV tissue, Gal-3 was present in macrophages rather than myocytes but Gal-3+/CD-68+ cells per HPF was not correlated with plasma Gal-3 levels (p> 0.9) which correlated inversely with eGFR (r = -0.89 for log Gal-3 vs eGFR, p<0.0001). In the kidney, Gal-3 was not present in macrophages but was localized to renal tubular cells (Figure). The CG3S increased exponentially as eGFR decreased (r = - 0.88 for log CG3S versus eGFR; p<0.0001) and this relationship was not different (p=0.44) in patients with or without HF (Figure). The log CG3S correlated with the degree of fibrosis (tubulointerstitial scarring) in the kidney (r=0.88; p<0.0001). Conclusion: Collectively, these data suggest that plasma Gal-3 is predominantly of renal tubular epithelial origin in human HF, CKD, and CKD+HF.

Aims The outcomes of patients presenting with acute myocarditis and life‐threatening ventricular arrhythmias (LT‐VA) are unclear. The aim of this study was to assess the incidence and predictors of recurrent major arrhythmic events (MAEs) after hospital discharge in this patient population. Methods and results We retrospectively analysed 156 patients (median age 44 years; 77% male) discharged with a diagnosis of acute myocarditis and LT‐VA from 16 hospitals worldwide. Diagnosis of myocarditis was based on histology or the combination of increased markers of cardiac injury and cardiac magnetic resonance (CMR) Lake Louise criteria. MAEs were defined as the relapse, after discharge, of sudden cardiac death or successfully defibrillated ventricular fibrillation, or sustained ventricular tachycardia (sVT) requiring implantable cardioverter‐defibrillator therapy or synchronized external cardioversion. Median follow‐up was 23 months [first to third quartile (Q1–Q3) 7–60]. Fifty‐eight (37.2%) patients experienced MAEs after discharge, at a median of 8 months (Q1–Q3 2.5–24.0 months; 60.3% of MAEs within the first year). At multivariable Cox analysis, variables independently associated with MAEs were presentation with sVT [hazard ratio (HR) 2.90, 95% confidence interval (CI) 1.38–6.11]; late gadolinium enhancement involving ≥2 myocardial segments (HR 4.51, 95% CI 2.39–8.53), and absence of positive short‐tau inversion recovery (STIR) (HR 2.59, 95% CI 1.40–4.79) at first CMR. Conclusions Among patients discharged with a diagnosis of myocarditis and LT‐VA, 37.2% had recurrences of MAEs during follow‐up. Initial CMR pattern and sVT at presentation stratify the risk of arrhythmia recurrence.

We present an adolescent African American male admitted to the cardiac intensive care unit with cardiogenic shock and acute respiratory failure. Through an overview of his presentation, diagnostic workup, and treatment, we demonstrate the clinical utility of genetic testing in the evaluation of unexplained dilated cardiomyopathies.

Abstract Background/Introduction Truncating variants in TTN-encoded titin (TTNtvs) underlie ∼25% of familial dilated cardiomyopathy (DCM) cases. In addition, TTNtvs are over-represented in alcoholic, peripartum, and chemotherapy-induced CM suggesting that risk factors may play a substantive role in the penetrance and expressivity of TTN-mediated DCM. Purpose To determine the prevalence and clinical impact of risk factors for TTN-mediated DCM within a single center cohort of unrelated patients with pathogenic (P)/likely pathogenic (LP) TTNtvs. Methods In this retrospective study, an institutionally developed natural language processing algorithm was used to identify all TTNtv-positive patients evaluated clinically between 01/2012 and 12/2019. Each TTNtv was then mapped to the TTN reference sequence (NM_133378.4) and classified according to a strict interpretation of the 2015 American College of Medical Genetics and Genomics (ACMG) guidelines. After exclusion of individuals with complex congenital heart disease, ischemic heart disease, and those without ACMG P/LP TTNtvs, available medical records were reviewed for risk factors such as long-term heavy alcohol consumption (&gt;80 grams/day), cardiotoxic chemotherapy exposure, morbid obesity (body mass index &gt;40), biopsy/imaging-confirmed myocarditis, peripartum/tachycardia-mediated CM, and valvular heart disease. Results Overall, 33 ACMG P/LP TTNtv-positive patients were identified (40% female; mean age at presentation 45±16 years; mean LVEF at presentation 38%±17%). Of note, 17/33 (52%) presented with heart failure (HF) and 4/33 (12%) presented with sustained ventricular arrhythmias (VAs). The remaining 12 (36%) TTNtv-positive patients presented with incidentally detected asymptomatic left ventricular systolic dysfunction (n=9) or as a result of genetic cascade screening (n=3). In comparison to TTNtv-positive patients with non-HF presentations, those with HF had worse left ventricular function (mean LVEF: 26% ± 11% vs 51% ±12%; p&lt;0.001) and were more likely to have ≥1 risk factor [11/17 (65%) vs 4/16 (25%); p=0.04]. Unexpectedly, the 7 TTNtv-positive patients that presented with (n=4) or subsequently developed (n=3) sustained VAs were younger at the time of presentation (34±13 years vs 48±15 years; p=0.04) and displayed a similar degree of left ventricular dysfunction to those without sustained VAs (mean LVEF: 42% ± 17% vs 36% ± 17%; p=ns). Interestingly, the only risk factor over-represented amongst those with sustained VAs was bileaflet mitral valve prolapse [3/7 (43%) vs 0/26 (0%); p=0.006]. Conclusion The majority of TTNtv-positive patients (14/23; 61%) with a history of HF and/or sustained VAs possessed ≥1 acquired risk factor providing further evidence that gene-environment interaction(s) exert a crucial role in the manifestation of TTN-mediated disease. Funding Acknowledgement Type of funding source: None

Abstract Background Heart transplant (HTx) patients can develop graft dysfunction (GD) without biopsy evidence of cell or antibody mediated rejection. Cardiac MRI (CMR) can detect inflammatory or infiltrative causes of cardiomyopathy however CMR findings in HTx recipients with GD have not been previously described. Purpose We sought to identify CMR characteristics of HTx patients with GD, and evaluate its additive value in its diagnosis and prognosis. Methods CMR has been performed routinely to evaluate GD at our institutions. There were 37 HTx recipients who presented with acute decline in left ventricular ejection fraction (LVEF) of &lt;50% and &gt;10% from baseline, with no biopsy evidence of rejection between 2007 and 2018. Coronary angiogram with IVUS was done to rule out allograft vasculopathy. Treatment of GD was per discretion of the treating clinician. Responders were defined as those with LVEF improvement &gt;10% at 180 days or greater post-presentation. LV and RV indices, the presence and pattern of late gadolinium enhancement (LGE) were determined by CMR. Results There were 34% females and mean age at transplant was 49±13 years. Median time from HTx to GD was 1.2 years. Presenting symptoms were heart failure (n=25), cardiogenic shock (n=1) and 11 patients were asymptomatic. Mean LVEF at presentation was 37±12% and donor specific antibodies were detected in 38% patients. Most patients were treated with steroid bolus (n=29), and/or plasmapheresis (n=23). There were no major changes made in immunosuppression in 6 patients. Delayed enhancement MRI was performed with standard inversion-recovery (IR) gradient echo sequences, between 5 and 20 minutes after institutional-standard protocol administration of IV gadolinium contrast. Biventricular LGE was present in 18/37 (49%) patients with GD and was more prevalent in responders (57%, 13 of 23) than non-responders (35%, 5 of 14), although not statistically significant (p=0.21). There were two patterns of LGE noted: 1) Diffuse epicardial (10 patients out which 9 were responders) and 2) Patchy pattern with non-specific distribution (8 patients out of which 4 were responders). Myocardial edema by triple IR sequencing was seen in 6 patients, all having diffuse epicardial pattern of enhancement matching the delayed enhancement pattern. When comparing different treatment groups, among those treated for GD (n=31), 12 of 21 (57%) responders had LGE and 4 of 10 (40%) non-responders had LGE (p=0.37), a pattern similar to the broader population. Among those not treated for GD (n=6), 1 of 2 responders had LGE and 1 of 4 non-responders had LGE (p=0.5). Conclusion CMR identified inflammation as a potential cause of GD in approximately 50% of HTx patients. There are 2 distinct patterns of LGE observed in GD, diffuse epicardial (56%) and patchy (44%). Although the presence of LGE in itself is not associated with myocardial recovery, 90% of patients with a diffuse epicardial pattern have recovery of GD. Funding Acknowledgement Type of funding source: None

Background The presence of a durable left ventricular assist device ( LVAD ) is associated with increased risk of vasoplegia in the early postoperative period following heart transplantation ( HT ). However, preoperative predictors of vasoplegia and its impact on survival after HT are unknown. We sought to examine predictors and outcomes of patients who develop vasoplegia after HT following bridging therapy with an LVAD . Methods and Results We identified 94 patients who underwent HT after bridging with continuous‐flow LVAD from 2008 to 2018 at a single institution. Vasoplegia was defined as persistent low vascular resistance requiring ≥2 intravenous vasopressors within 48 hours after HT for >24 hours to maintain mean arterial pressure >70 mm Hg. Overall, 44 patients (46.8%) developed vasoplegia after HT . Patients with and without vasoplegia had similar preoperative LVAD , echocardiographic, and hemodynamic parameters. Patients with vasoplegia were significantly older; had longer LVAD support, higher preoperative creatinine, longer cardiopulmonary bypass time, and higher Charlson comorbidity index; and more often underwent combined organ transplantation. In a multivariate logistic regression model, older age (odds ratio: 1.08 per year; P =0.010), longer LVAD support (odds ratio: 1.06 per month; P =0.007), higher creatinine (odds ratio: 3.9 per 1 mg/dL; P =0.039), and longer cardiopulmonary bypass time (odds ratio: 1.83 per hour; P =0.044) were independent predictors of vasoplegia. After mean follow‐up of 4.0 years after HT , vasoplegia was associated with increased risk of all‐cause mortality (hazard ratio: 5.20; 95% CI, 1.71–19.28; P =0.003). Conclusions Older age, longer LVAD support, impaired renal function, and prolonged intraoperative CPB time are independent predictors of vasoplegia in patients undergoing HT after LVAD bridging. Vasoplegia is associated with worse prognosis; therefore, detailed assessment of these predictors can be clinically important.