Clinical trial NCT02888561: Haemodynamic Effects of Dobutamine and Nitrite in LV Dysfunction
Official title: The Impact of Dobutamine and Nitrite on Myocardial Supply and Demand in Heart Failure
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Heart Failure
Lead sponsor: King's College London
Sponsor class: OTHER
First posted: 2016-09-05
Enrollment: 45
Sex: ALL
Minimum age (years): 18
Maximum age (years): 100
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients referred for diagnostic coronary angiography following a diagnosis of heart failure, with a left ventricular ejection fraction of less than or equal to 40%.

Brief summary: Patients with poor heart function can, in certain situations, have a further weakening of the heart muscle such that it becomes difficult to provide enough blood to the brain and other organs. In these cases, heart function can be supported by the use of medicines or heart pumps. One of the most widely used medicines is Dobutamine, given as an infusion (a drip). Although Dobutamine has been in use for decades and does improve blood flow to the organs, previous studies have not shown any impact on recovery of heart muscle function and survival. Key to unravelling this discrepancy is to understand the precise effects of Dobutamine on the oxygen supply to, and oxygen usage by, the heart muscle. We also aim to find out whether simultaneous infusion of another drug called Nitrite (naturally occurring substance that is found in beetroot for example, much like GTN) can enhance the beneficial effects of Dobutamine on the oxygen supply-demand balance of the heart. In recent years, major advances in technology mean that it is now possible to obtain this information in patients undergoing coronary angiography procedures by making detailed measurements of heart muscle function and blood flow in the heart arteries using a conductance catheter (measures volume and pressure within the main pumping chamber of the heart) and the Combowire (dual pressure and flow sensor tip angioplasty guidewire). The aim of this study is to understand the effect of a brief infusion of Dobutamine and nitrite on heart muscle function, oxygen supply and oxygen usage through this use of this technology, directly following the patients routine coronary angiogram. Patients will have these measurements taken using the technology described above during the infusion of both dobutamine and nitrite, inserted through blood vessels that reach the heart.


Eligibility criteria: Inclusion Criteria:

1. Left Ventricular Ejection Fraction \<40%
2. Patients aged \>18 years
3. Able to provide written consent

Exclusion Criteria:

1. Known acquired or congenital structural heart disease such as severe valve disease, ventricular/atrial septal defects
2. Haemodynamic Instability
3. Severe disease in major proximal coronary arteries or planned percutaneous coronary intervention during the index procedure

Primary outcomes:
measure: Coronary Flow (average peak velocity)
timeFrame: During procedure.
measure: left ventricular stroke work
timeFrame: during procedure
Secondary outcomes:
measure: rate pressure product
timeFrame: during procedure
measure: pressure volume area
timeFrame: during procedure
measure: coronary microvascular resistance
timeFrame: during procedure
measure: stroke volume
timeFrame: during procedure
measure: Distal tissue perfusion
timeFrame: during procedure
measure: Magnitude of forward compression wave
timeFrame: during procedure
measure: magnitude of backward expansion wave
timeFrame: during procedure
Other outcomes:
Locations:
city: London
country: United Kingdom
facility: British Heart Foundation Centre of Excellence, The Rayne Institute, KCL, at Guy's and St Thomas' NHS Foundation Trust
Study officials:
References: