Cardio-renal effects of the A1 adenosine receptor antagonist SLV320 in patients with heart failure.

BACKGROUND: Blocking the tubuloglomerular feedback mechanism with adenosine A1 receptor antagonists seems to improve diuresis and sodium excretion without compromising the glomerular filtration rate in patients with heart failure. However, the direct cardiac effects of this compound class have not been investigated to date. METHODS AND RESULTS: In total, 111 patients (109 men and 2 women) received a 1-hour infusion of 5, 10, and 15 mg SLV320, an adenosine A1 receptor antagonist, placebo, or 40 mg furosemide. Mean age was 57.9 years, mean ejection fraction was 28.1%, 82 patients were of New York Heart Association class II, and 29 patients were of New York Heart Association class III. Hemodynamic parameters (heart rate, blood pressure, pulmonary capillary wedge pressure, mean pulmonary arterial pressure, systemic vascular resistance, right atrial pressure, and cardiac output) were determined. Kidney function was assessed by cystatin C measurements and by analysis of urine output and urine electrolytes. In addition, pharmacokinetics of SLV320 and ex vivo inhibition of adenosine A1 receptor activity were performed. SLV320 was well tolerated, and no serious adverse events were observed. Heart rate, blood pressure, pulmonary capillary wedge pressure, mean pulmonary arterial pressure, right atrial pressure, and cardiac output were not altered by any dose of SLV320. Pulmonary capillary wedge pressure was significantly (P=0.04) decreased by furosemide (-6.2+/-5.9 mm Hg). Systemic vascular resistance was significantly (P=0.04) increased in the furosemide group (+166.70+/-261.87 dynes . s(-1) . cm(-5)), whereas all SLV320 groups showed no significant alterations of systemic vascular resistance. Changes from baseline cystatin C plasma concentrations decreased after 10 mg SLV320 (-0.093+/-0.137 mg/L, P=0.046), whereas furosemide resulted in a significant (P=0.03) increase of cystatin C (+0.052+/-0.065 mg/L) versus baseline. All values represent mean changes+/-SD from baseline at 3 hours postdosing: SLV320 (10 and 15 mg) increased significantly sodium excretion and diuresis compared with placebo during the 0- to 6-hour collection period postdosing. CONCLUSIONS: SLV320 infusion shows no immediate effects on cardiac hemodynamics. SLV320 might improve glomerular filtration rate while simultaneously promoting natriuresis and diuresis. Clinical Trial Registration- clinicaltrials.gov Indentifier: NCT00160134.

Highly purified omega-3 polyunsaturated fatty acids are effective as adjunct therapy for secondary prevention of myocardial infarction.

Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico (GISSI)-Prevenzione was the first large randomized trial to produce evidence that a pharmaceutical preparation of highly purified omega-3 polyunsaturated fatty acids (PUFAs), administered as an adjunct to other accepted interventions, had a favorable effect on hard clinical end-points in post-myocardial infarction patients. Much of the 20% all-cause mortality benefit recorded during the study could be attributed to a 45% reduction in sudden death--a fatal outcome that traditionally has proved resistant to medical intervention. These results were obtained with an omega-3 PUFA dose of 1 g/day, which is much lower than was routinely being used at the time the study was initiated (e.g. 4 g/day for hypertriglyceridemia). One consequence of this low-dose regimen was that the tolerability profile of omega-3 PUFAs during GISSI-Prevenzione was considered highly satisfactory, with low adverse event incidence rates and low rates of discontinuation due to adverse events. Time-course analysis established that much of the survival benefit of omega-3 PUFA treatment in GISSI-Prevenzione was realized during the early months of the trial. The beneficial effects of omega-3 PUFA treatment were observed on top of standard, secondary pharmacological prevention therapy like anti-platelet agents, statins, beta-blockers and angiotensin-converting enzyme (ACE) inhibitors. The benefits of omega-3 PUFA therapy were also apparent in patients at all standards of adherence to a healthy diet and may have been augmented in patients with the best dietary profile. Patients with diabetes mellitus (approximately 15% of the study cohort) appeared to benefit from omega-3 PUFAs to at least the same extent as the general study population; the treatment effect on sudden death was progressively more pronounced as left ejection fraction declined. Cost-effectiveness analyses undertaken from a third-party payer perspective for Italy revealed that the cost of low-dose treatment with highly purified omega-3 PUFAs was approximately Euro 25,000 per life-year gained.

Effect of Omacor on HRV parameters in patients with recent uncomplicated myocardial infarction - A randomized, parallel group, double-blind, placebo-controlled trial: study design [ISRCTN75358739].

BACKGROUND: A large body of data derived from animal, epidemiological and clinical studies indicate that n-3 polyunsaturated fatty acids have a favourable effect on the prognosis of patients with cardiovascular disease in general, and on reducing sudden death in particular.Depressed heart rate variability (HRV), an indicator of impairment of the autonomic nervous system, has been shown to be a powerful predictor of subsequent mortality in patients surviving an acute myocardial infarction. A multitude of studies have demonstrated this strong association, suggesting that the imbalance in the sympathic/parasympathetic system may facilitate emergence of ventricular arrhythmias.Heart rate variability parameters will be assessed in the present study, with the primary objective of evaluating the possible superiority of Omacor (a highly refined, concentrated omega-3 fatty acid) versus placebo in improving HRV from baseline to endpoint in patients with recent uncomplicated myocardial infarction. Both groups will receive optimal conventional treatment.The study will also explore and quantify improvement in time domain HRV indices and will assess the safety of administering Omacor to optimally treated post-infarction patients (conventional treatment). METHODS: This multi-centre study will evaluate the effect of Omacor 1 g, o.d. on time-domain HRV parameters in comparison to placebo o.d. in patients with recent uncomplicated transmural myocardial infarction.Patients will be screened during the first few days after the acute event as appropriate for the patient's condition, and after obtaining informed consent. Based on inclusion/exclusion criteria, a first 24-hour Holter recording will be performed. Two to five days later, screened patients still eligible for the study will undergo a second 24-hour Holter recording. After the second Holter recording, all patients will be randomly allocated to treatment with Omacor 1 g, o.d. or placebo o.d.One hundred patients will be followed in double-blind fashion for a six-month period after randomization. Visits, including 24-hour Holter recording and assessment of adverse events, will take place at one-month intervals +/- five days after randomization, i.e., six times in all.