The Effects of Decreasing the Lasix Dose on the Cardiorenal System
- Registration Number
- NCT00982423
- Lead Sponsor
- Mayo Clinic
- Brief Summary
The investigators' objective is to define the effects of decreasing the furosemide dose on heart, kidney and humoral function in people with compensated heart failure and kidney dysfunction and also in people with compensated heart failure without kidney dysfunction. Secondly, to define the humoral activation in both groups.
- Detailed Description
The broad objective of this protocol is to advance our understanding of the pathophysiological mechanisms of human Cardiorenal Syndrome (CRS) with a specific emphasis upon the biological interaction between diuretic therapy, the renin-angiotensin-aldosterone-system (RAAS) and cyclic 3'-5'-guanosine monophosphate (cGMP) pathway.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 41
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Arm && Interventions
Group Intervention Description Furosemide Furosemide Subjects received their clinically prescribed dose of furosemide for a 3 week stabilization period, then were assessed for cardiorenal and humoral function. Subjects then had a 50% reduction of the furosemide dose for a 3 week stabilization period, and were assessed for cardiorenal and humoral function again.
- Primary Outcome Measures
Name Time Method Renal Function as Measured by Glomerular Filtration Rate (GFR) at Baseline and in Response to Decreasing Furosemide Dose 3 weeks, approximately 6 weeks Kidney function was measured by GFR determined by iothalamate clearance. GFR describes the flow rate of filtered fluid through the kidney measured in milliliters per minute per 1.73 m\^2 of body surface area. A lower GFR means the kidney is not filtering normally. An estimated GFR of less than 60 mg/min/1.73 m\^2 of body surface area is considered to be impaired kidney function.
- Secondary Outcome Measures
Name Time Method Renal Plasma Flow at Baseline and in Response to Decreasing Furosemide Dose 3 weeks, approximately 6 weeks Effective renal plasma flow (eRPF) is a measure used to calculate renal plasma flow (RPF) and hence estimate renal function. Renal plasma flow is the volume of blood plasma that flows through the kidneys per unit time, measured as ml/min.
Aldosterone at Baseline and in Response to Decreasing Furosemide Dose 3 weeks, approximately 6 weeks Aldosterone is part of the renin-angiotensin-aldosterone system (RAAS). Drugs that interfere with the secretion or action of aldosterone are in use as antihypertensives, like lisinopril, which lowers blood pressure by blocking the angiotensin-converting enzyme (ACE), leading to lower aldosterone secretion. The net effect of these drugs is to reduce sodium and water retention but increase retention of potassium.
Plasma Renin Activity at Baseline and in Response to Decreasing Furosemide Dose 3 weeks, approximately 6 weeks Plasma renin activity is a measure of the activity of the plasma enzyme renin, which plays a major role in the body's regulation of blood pressure, thirst, and urine output. Renin is an enzyme that hydrolyses angiotensinogen secreted from the liver into the peptide angiotensin I. Renin's primary function is to cause an increase in blood pressure, leading to restoration of perfusion pressure in the kidneys.
Angiotensin II at Baseline and in Response to Decreasing Furosemide Dose 3 weeks, approximately 6 weeks Renin activates the renin-angiotensin system by cleaving angiotensinogen, produced by the liver, to yield angiotensin I, which is further converted into angiotensin II by the angiotensin-converting enzyme (ACE) primarily within the capillaries of the lungs. Angiotensin II then constricts blood vessels, increases the secretion of antidiuretic hormone (ADH) and aldosterone, and stimulates the hypothalamus to activate the thirst reflex, each leading to an increase in blood pressure.
Plasma Cyclic Guanosine Monophosphate (cGMP) at Baseline and in Response to Decreasing Furosemide Dose 3 weeks, approximately 6 weeks Any change in atrial filling pressures leads to the release of atrial natriuretic peptides (ANP) from the heart. Once released, atrial peptides exert potent direct vasodilator and natriuretic actions by virtue of the ability to increase their intracellular second messenger, cGMP. Plasma cGMP correlates closely with the severity of congestive heart failure.
Trial Locations
- Locations (1)
Mayo Clinic
🇺🇸Rochester, Minnesota, United States