Inhibiting the Inflammatory Injury After Myocardial Ischemia Reperfusion With Plasma-Derived Alpha-1 Antitrypsin: A Post Hoc Analysis of the VCU-α1RT Study.

BACKGROUND: Despite the benefits of reperfusion in limiting myocardial injury, the infarct size continues to expand after reperfusion because of secondary inflammatory injury. Plasma-derived alpha-1 antitrypsin (AAT) inhibits the inflammatory injury in myocardial ischemia and reperfusion. To explore the effects of plasma-derived AAT on the inflammatory response to ischemia-reperfusion injury, we analyzed time-to-reperfusion and enzymatic infarct size estimates in a post hoc analysis of the VCU-α1RT clinical trial (clinicaltrials.gov NCT01936896). METHODS: Ten patients with ST-segment elevation acute myocardial infarction (STEMI) were enrolled in an open-label, single-arm treatment study of Prolastin C, plasma-derived AAT, at 60 mg/kg infused intravenously within 12 hours of reperfusion. Biomarkers were measured serially over the first 72 hours, and patients were followed clinically for the occurrence of new-onset heart failure, recurrent MI, or death. Twenty patients with STEMI who had been enrolled in previous randomized trials with identical inclusion/exclusion criteria and had been assigned to placebo served as historical controls. RESULTS: Time to percutaneous coronary intervention and time to drug did not significantly differ between groups. AAT-treated patients had a significantly shorter time-to-peak creatine kinase myocardial band (CK-MB) values (525 [480-735] vs. 789 [664-959] minute, P = 0.005) and CK-MB area under the curve (from 1204 [758-2728] vs. 2418 [1551-4289] U·day, P = 0.035), despite no differences in peak CK-MB (123 [30-196] vs. 123 [71-213] U/mL, P = 0.71). CONCLUSIONS: A single administration of Prolastin C given hours after reperfusion in patients with STEMI led to a significant shorter time to peak and area under the curve for CK-MB, despite similar peak CK-MB values. These preliminary data support the hypothesis that Prolastin C shortens the duration of the ischemia-reperfusion injury in patients with STEMI.

Severely Impaired Cardiorespiratory Fitness in Patients With Recently Decompensated Systolic Heart Failure.

Hospital admission for decompensated heart failure marks a critical inflection point in a patient's health. Despite the improvement in signs or symptoms during hospitalization, patients have a high likelihood of readmission, reflecting a lack of resolution of the underlying condition. Surprisingly, no studies have characterized the cardiorespiratory fitness of such patients. Fifty-two patients (38 [73%] male, age 57 [52 to 65] years, left ventricular ejection fraction 31% [24 to 38]) underwent cardiopulmonary exercise testing 4 (1 to 10) days after hospital discharge, when stable and without overt signs of volume overload. Transthoracic Doppler echocardiography, measurement of N-terminal pro-B-natriuretic peptide, and quality of life were also assessed. Aerobic exercise capacity was severely reduced: peak oxygen consumption (pVO2) was 14.1 (11.2 to 16.3) ml/kg/min. Ventilatory inefficiency as indicated by the minute ventilation carbon dioxide production relation (VE/VCO2 slope) >30 and oxygen uptake efficiency slope <2.0 was noted in 41 (77%) and 39 (75%) patients, respectively. Forty-five (87%) patients had 1 of 2 high-risk features (pVO2 < 14 ml/kg/min or VE/VCO2 >30). Perceived functional capacity, measured by the Duke Activity Status Index, was also severely reduced and correlated with pVO2. N-terminal pro-B-natriuretic peptide levels and early transmitral velocity/early mitral annulus velocity (E/e') ratio at echocardiography showed a modest correlation with lower pVO2. In conclusion, patients with recently decompensated systolic heart failure demonstrate severe impairment in cardiorespiratory fitness, severely limiting quality of life.

Usefulness of C-Reactive Protein Plasma Levels to Predict Exercise Intolerance in Patients With Chronic Systolic Heart Failure.

Patients with heart failure (HF) have evidence of chronic systemic inflammation. Whether inflammation contributes to the exercise intolerance in patients with HF is, however, not well established. We hypothesized that the levels of C-reactive protein (CRP), an established inflammatory biomarker, predict impaired cardiopulmonary exercise performance, in patients with chronic systolic HF. We measured CRP using high-sensitivity particle-enhanced immunonephelometry in 16 patients with ischemic heart disease (previous myocardial infarction) and chronic systolic HF, defined as a left ventricular ejection fraction ≤ 50% and New York Heart Association class II-III symptoms. All subjects with CRP >2 mg/L, reflecting systemic inflammation, underwent cardiopulmonary exercise testing using a symptom-limited ramp protocol. CRP levels predicted shorter exercise times (R = -0.65, p = 0.006), lower oxygen consumption (VO2) at the anaerobic threshold (R = -0.66, p = 0.005), and lower peak VO2 (R = -0.70, p = 0.002), reflecting worse cardiovascular performance. CRP levels also significantly correlated with an elevated ventilation/carbon dioxide production slope (R = +0.64, p = 0.008), a reduced oxygen uptake efficiency slope (R = -0.55, p = 0.026), and reduced end-tidal CO2 level at rest and with exercise (R = -0.759, p = 0.001 and R = -0.739, p = 0.001, respectively), reflecting impaired gas exchange. In conclusion, the intensity of systemic inflammation, measured as CRP plasma levels, is associated with cardiopulmonary exercise performance, in patients with ischemic heart disease and chronic systolic HF. These data provide the rationale for targeted anti-inflammatory treatments in HF.

Effects of Prolastin C (Plasma-Derived Alpha-1 Antitrypsin) on the acute inflammatory response in patients with ST-segment elevation myocardial infarction (from the VCU-alpha 1-RT pilot study).

Alpha-1 antitrypsin (AAT) has broad anti-inflammatory and immunomodulating properties in addition to inhibiting serine proteases. Administration of human plasma-derived AAT is protective in models of acute myocardial infarction in mice. The objective of this study was to determine the safety and tolerability of human plasma-derived AAT and its effects on the acute inflammatory response in non-AAT deficient patients with ST-segment elevation myocardial infarction (STEMI). Ten patients with acute STEMI were enrolled in an open-label, single-arm treatment study of AAT at 60 mg/kg infused intravenously within 12 hours of admission and following standard of care treatment. C-reactive protein (CRP) and plasma AAT levels were determined at admission, 72 hours, and 14 days, and patients were followed clinically for 12 weeks for the occurrence of new onset heart failure, recurrent myocardial infarction, or death. Twenty patients with STEMI enrolled in previous randomized trials with identical inclusion and/or exclusion criteria, but who received placebo, served as historical controls. Prolastin C was well tolerated and there were no in-hospital adverse events. Compared with historical controls, the area under the curve of CRP levels was significantly lower 14 days after admission in the Prolastin C group (75.9 [31.4 to 147.8] vs 205.6 [78.8 to 410.9] mg/l, p = 0.048), primarily due to a significant blunting of the increase occurring between admission and 72 hours (delta CRP +1.7 [0.2 to 9.4] vs +21.1 [3.1 to 38.0] mg/l, p = 0.007). Plasma AAT levels increased from admission (149 [116 to 189]) to 203 ([185 to 225] mg/dl) to 72 hours (p = 0.005). In conclusion, a single administration of Prolastin C in patients with STEMI is well tolerated and is associated with a blunted acute inflammatory response.

The inflammasome in myocardial injury and cardiac remodeling.

SIGNIFICANCE: An inflammatory response follows an injury of any nature, and while such a response is an attempt to promote healing, it may, itself, result in further injury. RECENT ADVANCES: The inflammasome is a macromolecular structure recently recognized as a central mediator in the acute inflammatory response. The inflammasome senses the injury and it amplifies the response by leading to the release of powerful pro-inflammatory cytokines, interleukin-1ß (IL-1ß) and IL-18. CRITICAL ISSUES: The activation of the inflammasome in the heart during ischemic and nonischemic injury represents an exaggerated response to sterile injury and promotes adverse cardiac remodeling and failure. FUTURE DIRECTIONS: Pilot clinical trials have explored blockade of the inflammasome-derived IL-1ß and have shown beneficial effects on cardiac function. Additional clinical studies testing this approach are warranted. Moreover, specific inflammasome inhibitors that are ready for clinical use are currently lacking.

Comparative safety of interleukin-1 blockade with anakinra in patients with ST-segment elevation acute myocardial infarction (from the VCU-ART and VCU-ART2 pilot studies).

Two pilot studies of interleukin-1 (IL-1) blockade in ST-segment elevation myocardial infarction (STEMI) showed blunted acute inflammatory response and overall favorable outcomes at 3 months follow-up. We hereby present a patient-level pooled analysis with extended follow-up of 40 patients with clinically stable STEMI randomized to anakinra, a recombinant IL-1 receptor antagonist, 100 mg/day for 14 days or placebo in a double-blinded fashion. End points included death, cardiac death, recurrent acute myocardial infarction (AMI), stroke, unstable angina, and symptomatic heart failure. Median follow-up was 28 (interquartile range 3 to 38) months. Sixteen patients (40%) had a total of 22 adverse cardiovascular events: 1 cardiac death, 4 recurrent AMI, 5 episodes of unstable angina pectoris requiring hospitalization and/or urgent revascularization, and 11 new diagnoses of heart failure. Treatment with anakinra was associated with a hazard ratio of 1.08 (95% confidence interval 0.31 to 3.74, p = 0.90) for the combined end point of death, recurrent AMI, unstable angina pectoris, or stroke and a hazard ratio of 0.16 (95% confidence interval 0.03 to 0.76, p = 0.008) for death or heart failure. In conclusion, IL-1 blockade with anakinra for 2 weeks appears, therefore, to have a neutral effect on recurrent ischemic events, whereas it may prevent new-onset heart failure long term after STEMI.

Effects of interleukin-1 blockade with anakinra on aerobic exercise capacity in patients with heart failure and preserved ejection fraction (from the D-HART pilot study).

Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome of exercise intolerance due to impaired myocardial relaxation and/or increased stiffness. Patients with HFpEF often show signs of chronic systemic inflammation, and experimental studies have shown that interleukin-1 (IL-1), a key proinflammatory cytokine, impairs myocardial relaxation. The aim of the present study was to determine the effects of IL-1 blockade with anakinra on aerobic exercise capacity in patients with HFpEF and plasma C-reactive protein (CRP) >2 mg/L (reflecting increased IL-1 activity). A total of 12 patients were enrolled in a double-blind, randomized, placebo-controlled, crossover trial and assigned 1:1 to receive 1 of the 2 treatments (anakinra 100 mg or placebo) for 14 days and an additional 14 days of the alternate treatment (placebo or anakinra). The cardiopulmonary exercise test was performed at baseline, after the first 14 days, and after the second 14 days of treatment. The placebo-corrected interval change in peak oxygen consumption was chosen as the primary end point. All 12 patients enrolled in the present study and receiving treatment completed both phases and experienced no major adverse events. Anakinra led to a statistically significant improvement in peak oxygen consumption (+1.2 ml/kg/min, p = 0.009) and a significant reduction in plasma CRP levels (-74%, p = 0.006). The reduction in CRP levels correlated with the improvement in peak oxygen consumption (R = -0.60, p = 0.002). Three patients (25%) had mild and self-limiting injection site reactions. In conclusion, IL-1 blockade with anakinra for 14 days significantly reduced the systemic inflammatory response and improved the aerobic exercise capacity of patients with HFpEF and elevated plasma CRP levels.

Effects of interleukin-1 blockade with anakinra on adverse cardiac remodeling and heart failure after acute myocardial infarction [from the Virginia Commonwealth University-Anakinra Remodeling Trial (2) (VCU-ART2) pilot study].

A first pilot study of interleukin-1 blockade in ST-segment elevation acute myocardial infarction showed improved remodeling. In the present second pilot study, we enrolled 30 patients with clinically stable ST-segment elevation acute myocardial infarction randomized to anakinra, recombinant interleukin-1 receptor antagonist, 100 mg/day for 14 days or placebo in a double-blind fashion. The primary end point was the difference in the interval change in left ventricular (LV) end-systolic volume index between the 2 groups within 10 to 14 weeks. The secondary end points included changes in the LV end-diastolic volume index, LV ejection fraction, and C-reactive protein levels. No significant changes in end-systolic volume index, LV end-diastolic volume index, or LV ejection fraction were seen in the placebo group. Compared to placebo, treatment with anakinra led to no measurable differences in these parameters. Anakinra significantly blunted the increase in C-reactive protein between admission and 72 hours (+0.8 mg/dl, interquartile range -6.4 to +4.2, vs +21.1 mg/dl, interquartile range +8.7 to +36.6, p = 0.002), which correlated with the changes in LV end-diastolic volume index and LV end-systolic volume index at 10 to 14 weeks (R = +0.83, p = 0.002, and R = +0.55, p = 0.077, respectively). One patient in the placebo group (7%) died. One patient (7%) in the anakinra group developed recurrent acute myocardial infarction. More patients were diagnosed with new-onset heart failure in the placebo group (4, 27%) than in the anakinra group (1, 7%; p = 0.13). When the data were pooled with those from the first Virginia Commonwealth University-Anakinra Remodeling Trial (n = 40), this difference reached statistical significance (30% vs 5%, p = 0.035). In conclusion, interleukin-1 blockade with anakinra blunted the acute inflammatory response associated with ST-segment elevation acute myocardial infarction. Although it failed to show a statistically significant effect on LV end-systolic volume index, LV end-diastolic volume index, or LV ejection fraction in this cohort of clinically stable patients with near-normal LV dimensions and function, anakinra led to a numerically lower incidence of heart failure.