Download Hormones hold hope in heart disease

Hormones hold hope in
heart disease
Hormones released into the body as the result of heart disease may offer
clinicians a powerful tool in the diagnosis and treatment of cardiac conditions.
The Christchurch School of Medicine’s Cardioendocrine Research Group,
led by Professor Mark Richards, has established an international reputation for work on the relationship between hormones and cardiac stress and
injury such as heart attack.
Their biggest project is a clinical study involving 2000 patients, with coronary problems ranging from unstable angina to a full-blown heart attack,
in which they have been measuring various hormones generated by the
heart and other vascular tissue, as well as the kidneys, adrenal glands and
brain.
“We know from existing experience that in certain subgroups of heart disease these hormones are powerful indicators of the severity of heart disease
and the patient’s risk of deterioration. What we don’t know is how well we
can apply those measurements across a very broad group.
By coupling hormone measurements with measurements of the heart by
echocardiography, the team are developing a set of markers for assessing
whether people are at low, medium or high risk of further problems.
Another of the group’s projects is looking at subtle variations in genes,
which may alter people’s susceptibility to heart problems and their ability
to compensate for heart injury. While some people seem good at compensating for quite large injuries others seem to deteriorate rapidly.
The research team has recently discovered a common variant form of the
angiotensin converting enzyme (ACE) gene, which is associated with an
eight-fold increase in mortality over five years following a heat attack. In
future, knowing the form of the ACE gene may lead to early intervention
and improved survival.
Professor Richards and his team are also developing ways of measuring
newly discovered hormones so they can look at their levels in different patient groups. Hormones from the urocortin family are of particular interest
because they are already known to give considerable benefit to damaged
hearts in sheep, and the team is keen to see what they do in patients with
cardiac failure.
The therapeutic potential of hormones such as urocortin are also being investigated to see how they influence nervous traffic to the heart.
The team is examining the interaction of the sympathetic nervous system
with the heart, kidneys and hormones. It has a lot to do with how fast the
heart beats, as well as blood vessel tone and blood pressure.
Over the past two years the group has lodged three patent applications
with the NZ Patent Office. The group is currently collaborating with pharmaceutical companies in six ongoing studies, including phase I, phase II
and phase III trials.
This research is funded by the Health Research Council of New Zealand, the University of Otago, the National Heart Foundation, the Canterbury Medical Research
Foundation and the Lottery Grants Board, and with support from the pharmaceutical industry.
HRC19 2004
Level 3, 110 Stanley Street, Auckland PO Box 5541,
Wellesley Street, Auckland, NZ
Telephone 64 9 303 5200 Facsimile 64 9 377 9988
Website www.hrc.govt.nz
Health Research Council of New Zealand
Te Kaunihera Rangahau Hauora o Aotearoa
Dr Tim Yandle, Professor Gary Nicholls, and
Professor Mark Richards
Key words:
– cardiovascular disease, hormones,
ACE gene variants.
Key facts about cardiovascular
disease in New Zealand:
– leading cause of death (40%),
estimated to cost $306m- $467m
in early 1990s. Two to three times
higher death rate for Maori.
Aims of our research are to:
– better establish predictors of the
risk of onset of heart failure
– trial early interventions in the
groups discovered to be at risk.
What this research has shown:
– identified two cardiac natriuretic
peptide hormones as the strongest
prognostic markers of new cardiac
events in patients who have
already incurred heart attack or
heart failure
– patients with heart failure
most likely to respond to beta
blockade are those who have high
pretreatment hormone level
– results of a piloted heart failure
treatment guided by blood
hormone levels demonstrated that
this strategy may substantially
reduce mortality and hospital
readmission rates.