Borgeson, Daniel D.

Background Tricuspid valve surgery is recommended for severe isolated tricuspid regurgitation (TR) if symptoms persist despite optimal medical therapy. The definition of optimal therapy for TR is unclear beyond managing underlying conditions. Diuretics are the primary treatment for volume retention in TR, but it is unknown whether a “safe diuretic dose” exists for conservative management. We sought to evaluate the association between diuretic dose and outcomes. Methods Adult patients with ≥moderate–severe isolated TR were retrospectively identified from echocardiographic reports. Clinical and echocardiographic data were extracted from electronic medical records and manually reviewed. The primary end point was all‐cause mortality. Loop diuretic doses were converted to furosemide equivalent and categorized into 4 groups: <40 mg, 40 to 79 mg, 80 to 159 mg, and ≥160 mg daily. Results Of 1302 patients (age 72±13 years, 60% female), 565 (43%) had moderate–severe TR and 737 (57%) had severe TR. Median follow‐up was 8.7 (1.4, 14.0) years. Comorbidities increased with higher diuretic doses. A linear relationship between diuretic dose and mortality was observed in spline‐curve analysis. Hazard ratios (and CIs) for mortality adjusted for age, sex, coronary disease, chronic kidney disease, mild pulmonary hypertension, and New York Heart Association III/IV symptoms were 1.21 (0.96–1.53) ( P =0.12) for <40 mg, 1.50 (1.23–1.82) ( P <0.001) for 40 to 79 mg, 1.86 (1.46–2.37) ( P <0.001) for 80 to 159 mg, and 2.90 (2.18–3.88) ( P <0.001) for ≥160 mg furosemide equivalent. Any diuretic dose was associated with significant symptoms (New York Heart Association III–IV), with more patients experiencing symptoms at higher doses. Conclusion A daily loop diuretic dose ≥40 mg furosemide equivalent is associated with increased mortality and greater symptom severity in patients with TR.

Abstract Aims We aim to determine if our previously validated, diagnostic artificial intelligence (AI) electrocardiogram (ECG) model is prognostic for survival among patients with cardiac amyloidosis (CA). Methods A total of 2533 patients with CA (1834 with light chain amyloidosis (AL), 530 with wild-type transthyretin amyloid protein (ATTRwt) and 169 with hereditary transthyretin amyloid (ATTRv)] were included. An amyloid AI ECG (A2E) score was calculated for each patient reflecting the likelihood of CA. CA stage was calculated using the European modification of the Mayo 2004 criteria for AL and Mayo stage for transthyretin amyloid (ATTR). Risk of death was modelled using Cox proportional hazards, and Kaplan–Meier was used to estimate survival. Results Median age of the cohort was 67 [inter-quartile ratio (IQR) 59, 74], and 71.6% were male. The median overall survival for the cohort was 35.6 months [95% confidence interval (CI) 32.3, 39.5]. For AL, ATTRwt and ATTRv, respectively, median survival was 22.9 (95% CI 19.2, 28.2), 47.2 (95% CI 43.4, 52.3) and 61.4 (95% CI 48.7, 75.9) months. On univariate analysis, an increasing A2E score was associated with more than a two-fold risk of all-cause death. On multivariable analysis, the A2E score retained its importance with a risk ratio of 2.0 (95% CI 1.58, 2.55) in the AL group and 2.7 (95% CI 1.81, 4.24) in the ATTR group. Conclusions Among patients with AL and ATTR amyloidosis, the A2E model helps to stratify risk of CA and adds another dimension of prognostication.

Introduction: Transthyretin cardiac amyloidosis (TTR-CA) can cause heart failure with preserved EF (HFpEF). We previously reported a clinical/echo-based score (TCAS) and defined a cut-off that predicted risk of TTR-CA in HFpEF. Herein, we assess the comparative performance of an artificial-intelligence ECG-based screening tool (AI-ECG). Hypothesis: AI-ECG successfully identifies TTR-CA in HFpEF cohorts across a range of TTR-CA prevalence Methods: Referral HFpEF cohort was constructed from a referral population of HFpEF patients (EF ≥ 40%) undergoing 99m Tc-pyrophosphate scintigraphy (PYP) at Mayo Clinic (2013-2020, n=484, 38% with TTR-CA). Community HFpEF cohort was prospectively screened with PYP (n=275; age ≥ 60, LV wall thickness (WT) ≥ 12 mm, 4% with TTR-CA). TCAS was built using a multivariable logistic regression model and converted to a simple point score comprised of age (60-69, 70-79, ≥ 80: +2, +3, +4 points respectively), male sex (+2), relative WT > 0.57 (+2), posterior WT ≥ 12 mm (+1), EF < 60% (+1), and hypertension diagnosis (-1). TCAS was validated in the community cohort. A deep neural network trained to predict cardiac amyloidosis from a single 12-lead ECG, was applied to both referral and community cohorts. Patients were excluded if ECG was not available ≤ 12 months before PYP or if used in development of the AI-ECG. Standard ROC methods were applied. Youden’s index was used to define optimal cut-off. Results: Predictive characteristics of AI-ECG were strong and compared favorably with TCAS across a range of true TTR-CA prevalence (Table). Conclusions: Using a single ECG, AI-ECG effectively predicts TTR-CA with an excellent negative predictive value to rule out TTR-CA and a positive predictive value sufficient to warrant specific TTR-CA testing. This was particularly evident in the community. AI-ECG holds promise for simple, cost-effective global screening of at-risk populations, especially those with limited access to advanced cardiac imaging.

Abstract Background Wild type transthyretin cardiac amyloidosis (wtATTR-CA) is increasingly recognized as a cause of heart failure with preserved ejection fraction (HFpEF) but prognosis is often limited due to late or misdiagnosis.Longitudinal left ventricular strain and biomarkers are established as markers of disease severity, but the role of RV free wall strain, reflecting RV contractility, is less well understood. Purpose We sought to determine whether RV free wall strain might add incremental prognostic value in wtATTR-CA. Methods Consecutive patients diagnosed with wtATTR-CA with tissue confirmation at Mayo clinic between 2013 and 2015 were included. Patients with TTR gene mutations were excluded. Baseline characteristics and transthoracic echocardiography measurements were obtained from the medical records. Speckle tracking RV free wall longitudinal 2D strain and peak LA longitudinal 2D strain were measured using Tom Tec Imaging System. Survival was determined using Kaplan Meier estimates and using the cox proportional hazard ratio, univariate and multivariable analysis were performed to identify predictors of mortality in patients with wtATTR. Results The study group comprised 139 patients (mean age 74.9±8.6, 92.8% male), of which 102 had adequate image quality for RV strain, and 99 for LA strain. Amongst these, 102 (73.3%) had AF and 118 patients (84.8%) had HF. During 3.23±2.0 years of follow up, 66 patients died. Both mean RV and LA strain were impaired at baseline: RV free wall strain was −14.7±4.9, and peak atrial longitudinal strain (PALS) was 13.2±8.8%. Using ROC analysis, RV strain of −16.8% was an independent predictor of all-cause mortality. In univariate modeling, higher levels of NT-proBNP (HR: 1.1 per 1000 pg.ml; 95%, CI 1.05–1.15, p&lt;0.001) and Troponin T (HR: 2.0 per 0.1ng/ml; 95% CI 1.49–2.61, p&lt;0.001) were associated with increased all-cause mortality. In addition, LV GLS (HR: 1.13 per 1%; 95% CI1.04–1.24, p=0.003), RV free wall LS (HR: 2.16 per 5%; 95%, CI 1.57–3.03, p&lt;0.0001), and PALS (HR: 0.91 per1%; 95% CI 0.85–0.96, p&lt;0.0001) were univariate predictors of all-cause mortality. In multivariate analysis using a stepwise regression model, RV free wall longitudinal strain (HR: 1.81; 95% CI 1.29–2.62, p&lt;0.001) and Troponin T (HR: 1.7; 95% CI 1.25–2.26, p=0.001) remained independent predictors. Kaplan-Meier survival analysis demonstrated a higher mortality rate above −16.8 RV strain cut-off (Wilcoxon &lt;0.0001). All stages were divided into two groups by −16.8% RV strain, and survival in individual stages analyzed. Stage 1 and 2 with &lt;−16.8 RV free wall strain value had higher mortality than ≤-16.8% RV strain (Stage 1: Wilcoxon = 0.0041 and Stage 2: Wilcoxon = 0.023). However, there was not a survival difference between two RV strain groups in stage3 (Wilcoxon = 0.34) Conclusion RV free wall strain is an independent predictor of survival in wtATTR patients and may add incremental prognostic value to NT-proBNP and Troponin. Funding Acknowledgement Type of funding sources: None. Kaplan-Meier curve of all patientsKaplan-Meier curve of stages

Endothelin-1 (ET-1) is a peptide that has been implicated in congestive heart failure (CHF). Although increased concentrations of circulating ET-1 have been repeatedly demonstrated, the activation of local ET-1 in target tissues of CHF remains poorly defined. Our objective was to characterize ET-1 tissue concentrations and gene expression of prepro ET-1 in myocardial, renal, and pulmonary tissue in rapid ventricular pacing-induced canine CHF. Progressive rapid ventricular pacing (38 days) resulted in impaired cardiovascular hemodynamics, increased atrial and left ventricular mass, decreased renal sodium excretion, and increased ET-1 plasma concentrations (all P < 0.05). Tissue analysis revealed significant increases in local ET-1 during CHF in left ventricular, renal, and pulmonary tissue, whereas a moderate increase in left atrial ET-1 did not reach statistical significance. In contrast, prepro-ET-1 gene expression was increased more than threefold in pulmonary tissue and more than twofold in left atrial myocardium with no increase in left ventricular or renal gene expression. The present studies demonstrate a differential pattern of ET-1 activation in cardiorenal and pulmonary tissue with a strong accumulation of ET-1 in kidney and lung during CHF. Although the observed increase in left ventricular and renal ET-1 in association with unaltered gene expression is consistent with increased uptake, pulmonary and atrial tissue may contribute to increased circulating and local ET-1 in CHF.

Controversy persists regarding the acute responsiveness of atrial (ANP) and brain (BNP) natriuretic peptides in pathophysiological conditions such as acute heart failure (AHF). This study was designed to test the hypothesis that AHF is characterized by selective activation of ANP, but not BNP. We also hypothesized that BNP replacement in AHF would reduce cardiac filling pressures, increase sodium excretion, and inhibit circulating renin. Two groups of anesthetized dogs underwent rapid left ventricular pacing to induce AHF. Group 1 (n = 7) served as control and group 2 (n = 7) received canine BNP (10 ng x kg(-1) x min(-1)). Cardiorenal parameters, circulating natriuretic peptides, 3',5'-cyclic guanosine monophosphate (cGMP), and plasma renin activity (PRA) were determined at baseline and during AHF in both groups. AHF was characterized by reductions in cardiac output (2.3 +/- 0.2 vs. 3.7 +/- 0.3 l/min, P < 0.05), pulmonary capillary wedge pressure (PCWP; 11.7 +/- 0.8 vs. 5.1 +/- 0.3 mmHg, P < 0.05), and selective activation of ANP (250 +/- 51 vs. 39 +/- 13 pg/ml, P < 0.05), with no increase in circulating BNP (49 +/- 15 vs. 60 +/- 16 pg/ml, P = not significant). Compared with control, exogenous supplemental BNP in AHF resulted in marked increases in circulating cGMP (65 +/- 6 vs. 18 +/- 5 pg/ml, P < 0.05), with reductions in PCWP (9.1 +/- 0.9 vs. 12.9 +/- 1.1 mmHg, P < 0.05) and increased urinary sodium excretion (120 +/- 36.8 vs. 24 +/- 6.3 microeq/min, P < 0.05) via reductions in distal tubular sodium reabsorption (94.3 +/- 1.8 vs. 98.0 +/- 0.4%, P < 0.05). Exogenous BNP prevented the increase in PRA that occurred in the control group. We conclude that AHF is characterized by a failure to increase circulating BNP underscoring differential physiological and pathophysiological roles for ANP and BNP in states of immediate cardiac overload. These studies also support a potential role for BNP in the therapeutics of AHF.

Adrenomedullin (ADM) is a new member of a family of vasodilating and natriuretic peptides that plays an important role in cardiorenal regulation. This study was designed to establish the plasma, urinary, cardiac, and renal tissue concentrations and immunohistochemical localizations of ADM in normal dogs and dogs with experimental congestive heart failure (CHF) produced by rapid ventricular pacing. Plasma ADM concentration was 5.6 ± 0.4 pg/ml in normal dogs and significantly increased to 14.5 ± 2.5 pg/ml in CHF dogs ( P < 0.05). Ventricular and renal tissue ADM were significantly increased in CHF dogs compared with normals. Immunohistochemical examination revealed positive ADM immunostaining within the myocytes, and ventricular ADM immunoreactivity was significantly more intense in CHF dogs than in normals. ADM immunoreactivity was also observed in the glomerulus, distal tubules, and medullary collecting duct cells in the kidney, and the intensities of ADM immunoreactivity in these sites were increased in CHF dogs compared with normals. In addition, ventricular ADM was a powerful marker for left ventricular mass, and circulating ADM correlated positively with left ventricular end-diastolic pressure and inversely with cardiac output and ejection fraction. Despite an increase in renal tissue ADM, urinary ADM did not increase in CHF dogs. The current study demonstrates that plasma concentration of ADM is increased in experimental CHF and that ventricular and renal ADM is activated in the progression of CHF. Tissue and circulating ADM also are markers for the alterations in myocardial structure and function. This study supports a potential role for ADM in the neurohumoral activation in experimental CHF.

Although brain natriuretic peptide (BNP) of myocardial origin is important in cardiovascular and renal function and as a marker of cardiac dysfunction, the expression of BNP in atrial and ventricular myocardium remains controversial both under normal conditions and in heart failure. We therefore determined left atrial and left ventricular (LV) gene expression and tissue concentration as well as circulating BNP during the evolution of rapid ventricular pacing-induced congestive heart failure (CHF) in the dog. Early LV dysfunction after 10 days of pacing was characterized by impaired LV function but maintained arterial pressure, and overt CHF after 38 days of pacing was characterized by further impaired LV function and decreased systemic arterial pressure. Under normal conditions, cardiac BNP mRNA and cardiac tissue BNP were of atrial origin. In early LV dysfunction, BNP mRNA and tissue BNP were markedly increased in the left atrium in association with an increase in circulating BNP but remained below or at the limit of detection in the LV. In overt CHF, BNP mRNA was further increased in the left atrium and first increased in the LV, together with an increase in LV tissue BNP and a further increase in circulating BNP. In the progression of CHF, early LV dysfunction is characterized by a selective increase in atrial BNP expression in association with increased circulating BNP. Overt CHF is characterized by an additional recruitment of ventricular BNP expression and a further increase in circulating BNP. These studies provide important new insight into the local and temporal regulation of cardiac BNP gene expression during the progression of heart failure and underscore the predominant endocrine role of atrial myocardium under normal conditions and in early LV dysfunction.

Among patients undergoing cardioversion for atrial fibrillation, the presence of left ventricular thrombus is a relatively uncommon and challenging clinical dilemma. While left atrial appendage thrombus is a contraindication to cardioversion, there is paucity of data regarding the safety of cardioversion in with the presence of left ventricular apical thrombus. Also, thrombus characteristics such as protrusion and mobility on echocardiography are known risk factors for systemic embolism. In this article, we present a case highlighting the management of atrial fibrillation in the setting of left ventricular dysfunction, acute heart failure, and echocardiographic evidence of acute left ventricular apical thrombus.