Subclinical Myocardial Injury and the Phenotype of Clinical Congestion in Patients With Heart Failure and Reduced Left Ventricular Ejection Fraction

BACKGROUND

Clinical congestion is associated with adverse outcomes in patients with heart failure. The pathophysiological mediators of this association remain uncertain.

METHODS AND RESULTS

We prospectively enrolled a cohort of patients with heart failure and reduced left ventricular ejection fraction and performed a detailed clinical examination followed on the same day by an invasive right heart catheterization and blood sampling for biomarkers. High-sensitivity troponin T and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were measured. A clinical congestion score was calculated based on jugular venous pressure (cm H₂0 <10 = 0, 10-14 = 1, >14 = 2 points), bendopnea (0 vs 1), a third heart sound (0 vs 1), or peripheral edema (0-2). Congestion was categorized into tiers as absent (0 points), mild (1 point), or moderate to severe (≥ 2 points). We tested for associations of high-sensitivity troponin T, NT-proBNP, and elevated ventricular filling pressures with clinical congestion in both univariate and multivariable analyses. Of 153 participants, 65 (42%) had absent, 35 mild (23%), and 53 (35%) had moderate to severe clinical congestion. Congestion tier was associated with higher NT-proBNP and hs-troponin levels, and the right atrial pressure and pulmonary capillary wedge pressure (P < .001 for each). Increased congestion tier was also associated with the coexistent presence of elevated troponin T (≥52 ng/L), NT-proBNP (≥1000 pg/mL), and pulmonary capillary wedge pressure (≥22 mm Hg). Specifically, 78% of those with absent clinical congestion had 0 to 1 of these findings, whereas 75% of those with moderate-severe congestion had 2 or all 3 of these abnormalities (P < .001). An elevated hs-troponin was associated with mild or greater clinical congestion (odds ratio 3, 95% confidence interval 1.2-7.5, P = .02) in multivariable analysis adjusting for potential confounders including the right atrial pressure, pulmonary capillary wedge pressure, and NT-proBNP levels.

CONCLUSIONS

Clinical congestion is a phenotype in which there is a high coexistent presence of elevated ventricular filling pressures, elevated natriuretic peptide levels, and subclinical myocardial injury. An elevated troponin was associated with clinical congestion in multivariable models that adjusted for ventricular filling pressures and natriuretic peptide levels. These data strengthen the evidence base for an association of elevated troponin with clinical congestion, suggesting that subclinical myocardial injury may be an important contributor to the pathophysiology of the congested state.

Identifying Discordance of Right- and Left-Ventricular Filling Pressures in Patients With Heart Failure by the Clinical Examination

BACKGROUND

In ≈25% of patients with heart failure and reduced left-ventricular ejection fraction, right-ventricular (RV), and left-ventricular (LV) filling pressures are discordant (ie, one is elevated while the other is not). Whether clinical assessment allows detection of this discordance is unknown. We sought to determine the agreement of clinically versus invasively determined patterns of ventricular congestion.

METHODS

In 156 heart failure and reduced LV ejection fraction subjects undergoing invasive hemodynamic assessment, we categorized patterns of ventricular congestion (no congestion, RV only, LV only, or both) based on clinical findings of RV (jugular venous distention) or LV (hepatojugular reflux, orthopnea, or bendopnea) congestion. Agreement between clinically and invasively determined (RV congestion if right atrial pressure [RAP] ≥10 mm Hg and LV congestion if pulmonary capillary wedge pressure [PCWP] ≥22 mm Hg) categorizations was the primary end point.

RESULTS

The frequency of clinical patterns of congestion was: 51% no congestion, 24% both RV and LV, 21% LV only, and 4% RV only. Jugular venous distention had excellent discrimination for elevated RAP (C=0.88). However, agreement between clinical and invasive congestion patterns was poor, к=0.44 (95% CI, 0.34-0.55). While those with no clinical congestion usually had low RAP and PCWP (67/79, 85%), over one-half (24/38, 64%) with isolated LV clinical congestion had PCWP <22 mm Hg, most (5/7, 71%) with isolated RV clinical congestion had PCWP ≥22 mm Hg, and ≈one-third (10/32, 31%) with both RV and LV clinical congestion had elevated RAP but PCWP <22 mm Hg.

CONCLUSIONS

While clinical examination allows accurate detection of elevated RAP, it does not allow accurate detection of discordant RV and LV filling pressures.

Delayed febrile response with bloodstream infections in patients with continuous-flow left ventricular assist devices

Bloodstream infections (BSIs) are common in patients with continuous-flow left ventricular assist devices (CF-LVADs). Whether CF-LVADs modulate the febrile response to BSIs is unknown. We retrospectively compared the febrile response to BSIs in patients with heart failure (HF) with CF-LVADs versus a control population of patients with HF receiving inotropic infusions. BSIs were adjudicated using the Centers for Disease Control and Prevention and the National Healthcare Safety Network criteria. Febrile status (temperature ≥38°C, 100.4 °F), temperature at presentation with BSI, and the highest temperature within 72 hours (Tmax) were collected. We observed 59 BSIs in LVAD patients and 45 BSIs in controls. LVAD patients were more likely to be afebrile and to have a lower temperature at presentation than control (88% vs 58%, p=0.002, and 37°C ±0.7 vs 37.7°C ±1.0, p=0.0009, respectively). By 72 hours, the difference in afebrile status diminished (53% vs 44%, p=0.42), and the Tmax was similar between the LVAD and control groups (37.9°C±0.9 vs 38.2°C±0.8, respectively, p=0.10). In conclusion, at presentation with a BSI, the vast majority of CF-LVAD patients were afebrile, an event which occurred at a higher frequency when compared with patients with advanced HF on chronic inotropes via an indwelling venous catheter. These data alert clinicians to have a very low threshold to obtain blood cultures in CF-LVAD patients even in the absence of fever. Further study is needed to determine whether a delayed or diminished febrile response represents another pathophysiological consequence of CF-LVADs.