Harrington, Robert A.

Abstract Aims Heart failure (HF) with preserved (HFpEF) and mildly reduced (HFmrEF) ejection fraction are prevalent, yet frequently underdiagnosed syndromes associated with high morbidity and mortality, impaired quality of life, and escalating healthcare expenditures. Although guideline-directed medications like SGLT2 inhibitors have been shown to reduce the risk of hospitalization and cardiovascular death, their use remains limited and substantial residual risk persists. This trial aims to evaluate the safety and performance of a novel left-atrium-to-coronary-sinus shunt (Edwards APTURE transcatheter shunt system) in HFpEF and HFmrEF patients. Methods ALT-FLOW II is a prospective multi-centre, randomized, sham-controlled, double-blinded (patient and assessor) trial. Approximately 100 symptomatic HF patients aged ≥18 years with left ventricular ejection fraction >40% and exercise pulmonary capillary wedge pressure (PCWP) ≥25 mm Hg with a PCWP to right atrial pressure gradient ≥8 mm Hg will be randomized 1:1 to the APTURE shunt vs sham control. Key exclusion criteria include severe HF, significant valvular disease, and more than mild right ventricular dysfunction. The primary endpoints are the safety of the APTURE device at 30 days and change in workload-corrected PCWP normalized to bodyweight at 6 months. Secondary endpoints include changes in patient-reported outcomes, and hemodynamic and echocardiographic parameters through 5 years. The trial will also explore the impact of the device on short-term cardiac remodelling and intra-cardiac flow patterns using multi-modality imaging. Conclusions The ALT-FLOW II trial will evaluate the safety and performance of the APTURE system in symptomatic HFpEF and HFmrEF patients with elevated left atrial pressure.

Background: Refractory angina(Ang) effects 150 –250,000 pts in the US alone. These individuals have exhausted options for revasc and continue to have lifestyle limiting ang despite optimal medical Rx. Pre-clinical studies provided evidence that human CD34+ cells(CD34) can stimulate new blood vessel formation in ischemic myocardium(Myo), improving perfusion and function. We performed a phase 2 study of intraMyo injection of autologous CD34 in pts with CCS Class 3 and 4 Ang to obtain evidence for feasibility, safety and bioactivity. Methods: A phase 2 randomized, double-blind, placebo-controlled clinical trial was performed at 26 centers in the United States. There were 3 treatment groups: placebo, low dose (1×10^5 CD34/kg body wt) and high dose (5×10^5 CD34/kg). All pts underwent mobilization with GCSF 5 mcg/kg/day SC for 5 d, followed by apheresis on d5 to collect mononuclear cells. On day 6 CD34 were purified from the collected cells using the Isolex 300i device. After lot release testing, CD34 were injected endocardially at 10 locations in the ischemic Myo using the Myostar catheter following NOGA mapping. Placebo injections consisted of identical volumes of the diluent only. Results: A total of 167 pts were randomized and completed the injection procedure and 162 completed the 6 mo evaluation. The mean age of subjects was 61.0±8.9, there were 22 female and 145 male subjects. Trop was elevated in 26 pts at baseline and in 71 at some point following GCSF or injection. At 6 mo CD34 treated pts showed more reduction in ang frequency (−8.6 placebo vs 14.2 low dose) and improved ETT time (+69 sec placebo vs. +138 low dose). At 12m CD34 treated continue to show more reduction in angina (−8.2 placebo vs. −15.0 low dose) and improved ETT (+58 sec placebo vs. + 139 sec low dose). For key endpoints the high dose group results were inferior to low dose. The 12m data set has been locked and is being analyzed and the results of the completed analysis will be presented. Conclusions: Autologous CD34 cell therapy was associated with improved exercise tolerance and reduced angina in no-option pts with intractable angina. Ongoing analysis will determine endpoints, sample size and suitability of this therapy for a phase III study in no-option pts with refractory angina.

An increasing number of patients have refractory angina despite optimal medical therapy and are without further revascularization options. Preclinical studies indicate that human CD34 + stem cells can stimulate new blood vessel formation in ischemic myocardium, improving perfusion and function. In ACT34-CMI ( N = 167), patients treated with autologous CD34 + stem cells had improvements in angina and exercise time at 6 and 12 months compared to placebo; however, the longer-term effects of this treatment are unknown. ACT34 was a phase II randomized, double-blind, placebo-controlled clinical trial comparing placebo, low dose (1 × 10 5 CD34/kg body weight), and high dose (5 × 10 5 CD34/kg) using intramyocardial delivery into the ischemic zone following NOGA ® mapping. To obtain longer-term safety and efficacy in these patients, we compiled data of major adverse cardiac events (MACE; death, myocardial infarction, acute coronary syndrome, or heart failure hospitalization) up to 24 months as well as angina and quality of life assessments in patients who consented for 24-month follow-up. A total of 167 patients with class III–IV refractory angina were randomized and completed the injection procedure. The low-dose-treated patients had a significant reduction in angina frequency ( p = 0.02, 0.035) and improvements in exercise tolerance testing (ETT) time ( p = 0.014, 0.017) compared to the placebo group at 6 and 12 months. At 24 months, patients treated with both low-and high-dose CD34 + cells had significant reduction in angina frequency ( p = 0.03). At 24 months, there were a total of seven deaths (12.5%) in the control group versus one (1.8%) in the low-dose and two (3.6%) in the high-dose ( p = 0.08) groups. At 2 years, MACE occurred at a rate of 33.9%, 21.8%, and 16.2% in control, low-, and high-dose patients, respectively ( p = 0.08). Autologous CD34 + cell therapy was associated with persistent improvement in angina at 2 years and a trend for reduction in mortality in no-option patients with refractory angina.

Objective The effects of ticagrelor in the subpopulation of patients with ST-elevation myocardial infarction (STEMI) were consistent with those observed in the overall Platelet Inhibition and Patient Outcomes (PLATO) study. However, this subgroup included patients initially or ultimately treated conservatively. The aim of this study is to compare treatment using ticagrelor with treatment using clopidogrel in patients with STEMI undergoing primary percutaneous coronary intervention (PCI). Methods This post-hoc subgroup analysis compared ticagrelor with clopidogrel in 4949 PLATO patients with STEMI that were treated with primary PCI within 12 h of admission. The primary endpoint was cardiovascular death, myocardial infarction or stroke. The safety endpoint consisted of any major bleeding. Secondary endpoints included stent thrombosis. The analysis was not adequately powered to establish significance of any treatment effects. Results During a median of 286 days, the primary endpoint occurred in 7.9% of ticagrelor-treated patients versus 8.6% of clopidogrel-treated patients (HR 0.91, 95% CI 0.75 to 1.12, p=0.38). Major bleeding occurred in 6.7% in ticagrelor-treated patients versus 6.8% of clopidogrel-treated patients (HR 0.97, 95% CI 0.77 to 1.22, p=0.79). No interactions were observed for the treatment effect of ticagrelor versus clopidogrel on the primary efficacy (p=0.40) and primary safety endpoints (p=0.15) as compared with the full PLATO population. Treatment with ticagrelor versus clopidogrel reduced the occurrence of definite stent thrombosis (HR 0.58, 95% CI 0.37 to 0.89, p=0.013). Conclusions In the subset of patients with STEMI treated with primary PCI, ticagrelor compared with clopidogrel was safe, and efficacy outcomes were consistent with the overall PLATO trial. Trial registration number NCT00391872; Results.

Background —A multinational, randomized, placebo-controlled trial (Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy, PURSUIT) demonstrated that the platelet glycoprotein IIb/IIIa receptor antagonist eptifibatide reduced the incidence of death or myocardial infarction among patients with acute ischemic syndromes without ST-segment elevation. Because of expected differences in practice patterns, a prospectively planned analysis of outcomes as a function of regions of the world was performed. The current study provides a detailed assessment of eptifibatide among the subgroup of patients enrolled within the United States. Methods and Results —Patients presenting with chest pain within the previous 24 hours and ischemic ECG changes or creatine kinase–MB elevation were eligible for enrollment. Of the 10 948 patients randomized worldwide, 4035 were enrolled within the United States. Patients were allocated to placebo or eptifibatide infusion for up to 72 to 96 hours. Other medical therapies and revascularization strategies were at the discretion of the treating physician. Eptifibatide reduced the rate of the primary end point of death or myocardial infarction by 30 days from 15.4% to 11.9% ( P =0.003) among patients in the United States. The treatment effect was achieved early and maintained over a period of 6 months (18.9% versus 15.2%; P =0.004). Bleeding events were more common in patients receiving eptifibatide but were predominantly associated with invasive procedures. The magnitude of clinical benefit from eptifibatide was greater among patients in the United States than elsewhere in the world. Conclusions —Platelet glycoprotein IIb/IIIa receptor blockade with eptifibatide reduces the incidence of death or myocardial infarction among patients treated for acute ischemic syndromes without ST-segment elevation within the United States.

Background Thrombin plays an important role in the pathogenesis of acute coronary thrombosis. We studied the effects of a direct thrombin inhibitor, recombinant desulfatohirudin, and heparin on plasma levels (at 0, 4, 12, and 24 hours) of fibrinopeptide A (FPA), which reflects thrombin action, and prothrombin fragment F1.2, which reflects thrombin generation, in patients with unstable angina. Methods and Results Patients were randomized to one of two doses of heparin (n=50) (target activated partial thromboplastin time, 65 to 90 seconds or 90 to 110 seconds) or one of four doses of r-hirudin (n=113) (0.05, 0.10, 0.20, or 0.30 mg·kg −1 ·h −1 by infusion). r-Hirudin induced a dose-dependent decline in plasma FPA. At 24 hours, FPA levels with 0.1- to 0.3-mg·kg −1 ·h −1 r-hirudin regimens were significantly lower than with 0.05 mg·kg −1 ·h −1 r-hirudin; levels with 0.1- to 0.2-mg·kg −1 ·h −1 r-hirudin regimens were lower than with both heparin regimens. Plasma F1.2 did not decline significantly during therapy with heparin or hirudin except at 0.3 mg·kg −1 ·h −1 hirudin. At 24 hours, they were higher with the 0.05-mg·kg −1 ·h −1 r-hirudin regimen than with other regimens. For comparable levels of thrombin generation (F1.2 levels), FPA levels were higher in heparin patients than in hirudin patients. For the same FPA values, the corresponding F1.2 values were higher in the hirudin group. Conclusions Our findings provide evidence for distinct in vivo effects of the two agents and suggest that r-hirudin is a relatively more potent inhibitor of thrombin action but a less effective inhibitor of thrombin generation than heparin. The lower FPA levels in hirudin patients may reflect its ability to inactivate clot-bound thrombin. The relative clinical efficacies of the two agents need to be defined by clinical trials in progress.

Background— Outcomes in patients with mild to moderate renal function (RF) abnormalities presenting with acute coronary syndromes (ACS) are not well defined. Methods and Results— A convenience sample of 4 ACS trial databases including all enrolled patients was assessed to determine 30- and 180-day outcomes. The 4 trials were Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) IIb, GUSTO-III, Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT), and Platelet IIb/IIIa Antagonism for the Reduction of Acute coronary syndrome events in a Global Organization Network (PARAGON-A). Patients were stratified into ST-segment elevation (STE) and non–ST-segment elevation (NSE) groups and by the presence or absence of abnormal RF (creatinine clearance <70 mL/min). In the STE group, 7670 of 18 621 patients (41%) had abnormal RF. In the NSE group, 8152 of 19 304 (42%) had abnormal RF. Patients with abnormal RF were older, more often female, and more likely to have adverse baseline characteristics. They had higher mortality and higher mortality/nonfatal myocardial infarction (MI) at both 30 and 180 days, regardless of ST-segment status. Creatinine clearance was independently associated with risk of mortality (hazard ratio 0.79 in the STE group and 0.81 in the NSE group) and with risk of mortality/MI (hazard ratio 0.93) in the NSE group at 180 days. Conclusions— Patients presenting with ACS frequently have abnormal RF. Abnormal RF is a marker of adverse baseline clinical characteristics and is independently associated with increased risk of death and death/MI.