Tag: myocardial infarction

Categories : Cardiovascular DiseaseTags :

Red Blood Cells Exposed to Oxygen Deficiency Protect against Myocardial Infarction

On By ModernMedia
Source: Pixabay CC0

Red blood cells exposed to oxygen deficiency protect against myocardial infarction, according to a new study published in the Journal of Clinical Investigation. This study, conducted at Karolinska Institutet in collaboration with Karolinska University Hospital, also shows that that protection can be enhanced by a diet containing nitrate-rich vegetables, such as arugula and other green leafy vegetables.

“This effect was also shown in a clinical study in patients with high blood pressure who were randomly assigned to eat nitrate-rich vegetables or a diet low in nitrates,” says John Pernow, Professor of Cardiology at the Department of Medicine, Karolinska Institutet in Solna and senior physician at Karolinska University Hospital, and the study’s corresponding author together with Jon Lundberg, professor at the Department of Physiology and Pharmacology, Karolinska Institutet.

Part of the study was conducted through experiments with red blood cells from mice that were added to a myocardial infarction model with hearts from mice. Before the experiment, the red blood cells were exposed to low oxygen pressure, while nitrate was added to the drinking water.

In a clinical study, red blood cells were collected from patients with high blood pressure who were randomly assigned a nitrate-rich diet with green leafy vegetables or a diet with nitrate-poor vegetables. These red blood cells were given to the corresponding myocardial infarction model with hearts from rats.

“The results show both that the red blood cells convey protection against injury in the heart in the event of low oxygen levels, and how that protection can be enhanced through a simple dietary advice. This may be of great importance for patients at risk of myocardial infarction,” says the study’s first author Jiangning Yang, a researcher at the Department of Medicine, Solna, Karolinska Institutet.

The next step in the research is to develop additional drugs that can activate the protective signalling mechanism in red blood cells to provide protection to the body’s tissues and cells in the event of oxygen deficiency.

“In addition, we need to map how the blood cells transmit their protective signal to the heart muscle cells,” says John Pernow.

Source: Karolinska Institutet

Categories : Cardiovascular Disease COVIDTags :

European COVID Lockdowns Cost Heart Attack Patients up to Two Years of Life

On By ModernMedia
Photo by Camilo Jimenez on Unsplash

Patients who had heart attacks during the first COVID lockdown in the UK and Spain are predicted to live 1.5 and 2 years less, respectively, than their pre-COVID counterparts. That’s the finding of a study just published in European Heart Journal – Quality of Care and Clinical Outcomes.

“Restrictions to treatment of life-threatening conditions have immediate and long-term negative consequences for individuals and society as a whole,” said study author Professor William Wijns of the Lambe Institute for Translational Medicine, University of Galway, Ireland. “Back-up plans must be in place so that emergency services can be retained even during natural or health catastrophes.”

Research has shown that during the first wave of the pandemic, about 40% fewer heart attack patients went to hospital as governments told people to stay at home, fear of catching the virus, and the stopping of some routine emergency care. Compared to receiving timely treatment, heart attack patients who stayed at home were more than twice as likely to die, while those who delayed going to the hospital were nearly twice as likely to have serious complications that could have been avoided.

Heart attacks require urgent treatment with stents (called percutaneous coronary intervention or PCI) to open the blocked artery and restore blood flow. Delays, and the resulting lack of oxygen, lead to irreversible damage of the heart muscle and can cause heart failure or other complications. When a large amount of heart tissue is damaged, potentially fatal cardiac arrest results.

This study estimated the long-term clinical and economic implications of reduced heart attack treatment during the pandemic in the UK and Spain. The researchers compared the predicted life expectancy of patients who had a heart attack during the first lockdown with those who had a heart attack at the same time in the previous year. The study focused on ST-elevation myocardial infarction (STEMI), where a coronary artery is completely blocked. The researchers also compared the cost of STEMIs during lockdown with the equivalent period the year before.

A model was developed to estimate long-term survival, quality of life and costs related to STEMI. The UK analysis compared the period 23 March (when lockdown began) to 22 April 2020 with the equivalent time in 2019. The Spanish analysis compared March 2019 with March 2020 (lockdown began on 14 March 2020). Survival projections considered age, hospitalisation status and time to treatment using published data for each country. For example, using published data, it was estimated that 77% of STEMI patients in the UK were hospitalised prior to the pandemic compared with 44% during lockdown. The equivalent rates for Spain were 74% and 57%. The researchers also compared how many years in perfect health were lost for patients with a STEMI before versus during the pandemic.

The analysis predicted that patients who had a STEMI during the first UK lockdown would lose an average of 1.55 years of life compared to patients presenting with a STEMI before the pandemic. In addition, while alive, those with a STEMI during lockdown were predicted to lose approximately one year and two months of life in perfect health. The equivalent figures for Spain were 2.03 years of life lost and around one year and seven months of life in perfect health lost.

The cost analysis focused on initial hospitalisation and treatment, follow-up treatment, management of heart failure and productivity loss in patients unable to return to work. For example, the cost applied to a STEMI admission with PCI was £2837 in the UK and €8780 in Spain. Heart failure costs were estimated at £6086 in year one and £3882 in all subsequent years for the UK. The equivalent figures for Spain were €3815 (year one) and €2930 (each subsequent year).

Professor Wijns said: “The findings illustrate the repercussions of delayed or missed care. Patients and societies will pay the price of reduced heart attack treatment during just one month of lockdown for years to come. Health services need a list of lifesaving therapies that should always be delivered, and resilient healthcare systems must be established that can switch to emergency plans without delay. Public awareness campaigns should emphasise the benefits of timely care, even during a pandemic or other crisis.”

Source: European Society of Cardiology

Categories : Cardiovascular Disease ExerciseTags :

Strong Legs Reduce Risk of Heart Failure after Heart Attack

On By ModernMedia
Photo by Henry Xu on Unsplash

People with strong legs are less likely to develop heart failure after a heart attack, according to new research. Myocardial infarction is the most common cause of heart failure, with around 6–9% of heart attack patients going on to develop the condition. Previous research has shown that having strong quadriceps is associated with a lower risk of death in patients with coronary artery disease.

Presented at Heart Failure 2023, a scientific congress of the European Society of Cardiology (ESC), this study tested the hypothesis that leg strength is associated with a lower risk of developing heart failure after acute myocardial infarction. The study included 932 patients hospitalised in 2007 to 2020 with acute myocardial infarction who did not have heart failure prior to the admission and did not develop heart failure complications during their hospital stay. The median age was 66 years and 753 participants (81%) were men.

Maximal quadriceps strength was measured as an indicator of leg strength. Patients sat on a chair and contracted the quadriceps muscles as hard as possible for five seconds. A handheld dynamometer attached to the ankle recorded the maximum value in kg. The measurement was performed on each leg and the researchers used the average of both values. Strength was expressed relative to body weight, meaning that quadriceps strength in kg was divided by body weight in kg and multiplied by 100 for a % body weight value. Patients were classified as ‘high’ or ‘low’ strength according to whether their value was above or below the median for their se

The median value for women was 33% body weight and the median value for men was 52% body weight. A total of 451 patients had low quadriceps strength and 481 had high strength. During an average follow-up of 4.5 years, 67 patients (7.2%) developed heart failure. The incidence of heart failure was 10.2 per 1000 person-years in patients with high quadriceps strength and 22.9 per 1000 person-years in those with low strength.

The researchers analysed the association between quadriceps strength (low vs. high) and the risk of developing heart failure. The analysis was adjusted for factors known to be associated with the development of heart failure after myocardial infarction including age, sex, body mass index, prior myocardial infarction or angina pectoris, diabetes, atrial fibrillation, chronic obstructive pulmonary disease, peripheral arterial disease and kidney function. Compared with low quadriceps strength, a high strength level was associated with a 41% lower risk of developing heart failure (hazard ratio [HR]: 0.59; 95% confidence interval [CI] 0.35–1.00; p=0.048).

The investigators also analysed the association between quadriceps strength as a continuous variable and the risk of developing heart failure. Each 5% body weight increment in quadriceps strength was associated with an 11% lower likelihood of heart failure (HR 0.89; 95% CI 0.81–0.98; p=0.014).

Study author Mr. Kensuke Ueno, a physical therapist at the Kitasato University Graduate School of Medical Sciences, Sagamihara, Japan said: “Quadriceps strength is easy and simple to measure accurately in clinical practice. Our study indicates that quadriceps strength could help to identify patients at a higher risk of developing heart failure after myocardial infarction who could then receive more intense surveillance. The findings need to be replicated in other studies, but they do suggest that strength training involving the quadriceps muscles should be recommended for patients who have experienced a heart attack to prevent heart failure.”

Source: European Society of Cardiology

Categories : Cardiovascular Disease GenderTags :

Women Have Double the Mortality Risk After Heart Attack

On By ModernMedia

The risk of dying after a heart attack is more than twice as high for women than it is for men, according to research presented at Heart Failure 2023, held by the European Society of Cardiology (ESC).

“Women of all ages who experience a myocardial infarction are at particularly high risk of a poor prognosis,” said study author Dr Mariana Martinho of Hospital Garcia de Orta. “These women need regular monitoring after their heart event, with strict control of blood pressure, cholesterol levels and diabetes, and referral to cardiac rehabilitation. Smoking levels are rising in young women and this should be tackled, along with promoting physical activity and healthy living.”

Previous studies have found that women with ST-elevation myocardial infarction (STEMI) have a worse prognosis during their hospital stay compared to men, and that this may be due to their older age, increased numbers of other conditions, and less use of stents (percutaneous coronary intervention; PCI) to open blocked arteries. This study compared short- and long-term outcomes after STEMI in women and men, and examined whether any sex differences were apparent in both premenopausal (55 years and under) and postmenopausal (over 55) women.

This was a retrospective observational study which enrolled consecutive patients admitted with STEMI and treated with PCI within 48 hours of symptom onset between 2010 and 2015. Adverse outcomes were defined as 30-day all-cause mortality, five-year all-cause mortality and five-year major adverse cardiovascular events (MACE; a composite of all-cause death, reinfarction, hospitalisation for heart failure and ischaemic stroke).

The study included 884 patients. The average age was 62 years and 27% were women. Women were older than men (average age 67 vs 60 years) and had higher rates of high blood pressure, diabetes and prior stroke. Men were more likely to be smokers and have coronary artery disease. The interval between symptoms and treatment with PCI did not differ between women and men overall, but women aged 55 and below had a significantly longer treatment delay after arriving at the hospital than their male peers (95 vs 80 minutes).

The researchers compared the risk of adverse outcomes between women and men after adjusting for factors that could influence the relationship including diabetes, high cholesterol, hypertension, coronary artery disease, heart failure, chronic kidney disease, peripheral artery disease, stroke and family history of coronary artery disease. At 30 days, 11.8% of women had died compared to 4.6% of men, for a hazard ratio (HR) of 2.76. At five years, nearly one-third of women (32.1%) had died versus 16.9% of men (HR 2.33). More than one-third of women (34.2%) experienced MACE within five years compared with 19.8% of men (HR 2.10).

Dr Martinho said: “Women had a two to three times higher likelihood of adverse outcomes than men in the short- and long-term even after adjusting for other conditions and despite receiving PCI within the same timeframe as men.”

The researchers conducted a further analysis in which they matched men and women according to risk factors for cardiovascular disease including hypertension, diabetes, high cholesterol and smoking. Adverse outcomes were then compared between matched men and women aged 55 years and under, and between matched men and women over 55 years old.

There were 435 patients in the matched analysis. In matched patients over 55 years of age, all adverse outcomes measured were more common in women than men. Some 11.3% of women died within 30 days compared with 3.0% of men, for an HR of 3.85. At five years, one-third of women (32.9%) had died compared with 15.8% of men (HR 2.35) and more than one-third of women (34.1%) had experienced MACE compared with 17.6% of men (HR 2.15). In matched patients aged 55 years and below, one in five women (20.0%) experienced MACE within five years compared to 5.8% of men (HR 3.91), while there were no differences between women and men in all-cause mortality at 30 days or five years.

Dr Martinho said: “Postmenopausal women had worse short- and long-term outcomes after myocardial infarction than men of similar age. Premenopausal women had similar short-term mortality but a poorer prognosis in the long-term compared with their male counterparts. While our study did not examine the reasons for these differences, atypical symptoms of myocardial infarction in women and genetic predisposition may play a role. We did not find any differences in the use of medications to lower blood pressure or lipid levels between women and men.”

She concluded: “The findings are another reminder of the need for greater awareness of the risks of heart disease in women. More research is required to understand why there is gender disparity in prognosis after myocardial infarction so that steps can be taken to close the gap in outcomes.”

Source: European Society of Cardiology

Categories : Cardiovascular Disease GenderTags :

Atherosclerosis is a Greater Heart Attack Risk for Women

On By ModernMedia
Source: Wikimedia CC0

Postmenopausal women with atherosclerosis are at higher risk of heart attacks than men of similar age, according to research presented at EACVI 2023, a scientific congress of the European Society of Cardiology (ESC), and published in European Heart Journal – Cardiovascular Imaging. Researchers used imaging techniques to examine the arteries of nearly 25 000 patients and followed them for heart attacks and death.

“The study suggests that a given burden of atherosclerosis is riskier in postmenopausal women than it is in men of that age,” said study author Dr Sophie van Rosendael of Leiden University Medical Centre. “Since atherosclerotic plaque burden is emerging as a target to decide the intensity of therapy to prevent heart attacks, the findings may impact treatment. Our results indicate that after menopause, women may need a higher dose of statins or the addition of another lipid-lowering drug. More studies are needed to confirm these findings.”

While young women do have heart attacks, in general, women develop atherosclerosis (narrowing of arteries due to plaque buildup) later in life than men and have heart attacks at an older age than men, in part because of the protective effect of oestrogen. This study examined whether the prognostic importance of atherosclerotic plaques are the same for women and men at different ages as this could be important for selecting treatments to prevent heart attacks.

The study included 24 950 patients referred for coronary computed tomography angiography (CCTA) and enrolled in the CONFIRM registry, which was conducted in six countries in North America, Europe, and Asia. CCTA is used to obtain 3D images of the arteries in the heart.

Total atherosclerotic burden was rated using the Leiden CCTA score, which incorporates the following items for each coronary segment: plaque presence (yes/no), composition (calcified, noncalcified or mixed), location, and severity of narrowing, for a final value of 0 to 42. Patients were divided into three categories previously found to predict the risk myocardial infarction: low atherosclerotic burden (0 to 5), medium (6 to 20) and high (over 20). In addition, obstructive coronary artery disease was defined as 50% narrowing or more.

The primary outcome was the difference in Leiden CCTA score between women and men of similar age. The investigators also analysed sex differences in the rates of major adverse cardiovascular events (MACE), which included all-cause death and myocardial infarction, after adjusting for age and cardiovascular risk factors (hypertension, high cholesterol, diabetes, current smoking and family history of coronary artery disease).

A total of 11 678 women (average age 58.5 years) and 13 272 men (average age 55.6 years) were followed for 3.7 years. Regarding the primary outcome, the study showed an approximately 12 year delay in the onset of coronary atherosclerosis in women: the median Leiden CCTA risk score was above zero at age 64 to 68 years in women versus 52 to 56 years in men (p<0.001). In addition, the overall plaque burden as quantified by the Leiden CCTA score was significantly lower in women, who had more non-obstructive disease.

Dr. van Rosendael said: “The results confirm the previously reported delay in the start of atherosclerosis in women. We also found that women are more likely to have non-obstructive disease. It was formerly thought that only obstructive atherosclerosis caused myocardial infarction but we now know that non-obstructive disease is also risky.”
 
The burden of atherosclerosis was equally predictive of MACE in premenopausal women (aged under 55 years) and men of the same age group. However, in postmenopausal women (age 55 years and older), the risk of MACE was higher than men for a given score. In postmenopausal women, compared to those with a low burden, those with a medium and high burden had 2.21-fold and 6.11-fold higher risks of MACE. While in men aged 55 years and older, compared to those with a low burden, those with a medium and high burden had 1.57-fold and 2.25-fold greater risks of MACE.

Dr van Rosendael said: “In this study, the elevated risk for women versus men was especially observed in postmenopausal women with the highest Leiden CCTA score. This could be partly because the inner diameter of coronary arteries is smaller in women, meaning that the same amount of plaque could have a larger impact on blood flow. Our findings link the known acceleration of atherosclerosis development after menopause with a significant increase in relative risk for women compared to men, despite a similar burden of atherosclerotic disease. This may have implications for the intensity of medical treatment.”

Source: European Society of Cardiology

Categories : Cardiovascular DiseaseTags :

Time to Rethink Beta Blockers as Secondary Prevention for Heart Attack Survivors?

On By ModernMedia
Photo by Robina Weermeijer on Unsplash

Secondary prevention after a heart attack, where beta blockers are used over the long term to curb the risk of further heart attacks or death, doesn’t seem to be warranted in patients who don’t have heart failure, suggests a large study published in the journal Heart.

The researchers found no difference in these risks between patients taking beta blockers more than a year after their heart attack and those not on these drugs.

Beta blockers are mostly used to manage abnormal heart rhythms, as well as angina and high blood pressure. They are routinely prescribed after a heart attack as secondary prevention to lower the risk of recurrence and other cardiovascular complications.

But it’s not clear if these drugs are warranted in patients who don’t have heart failure, or a potentially fatal complication of heart attack known as left ventricular systolic dysfunction (LVSD) beyond the first year.

Most of the current evidence is based on the results of clinical trials that predate major changes to the routine care of heart attack patients, explain the researchers.

The researchers drew on 43 618 adults who had had a heart attack between 2005 and 2016 that required hospital treatment, and whose details had been entered into the national Swedish register for coronary heart disease (SWEDEHEART).

None of these patients had heart failure or LVSD: 34 253 of them were prescribed beta blockers and were still on these drugs 1 year after hospital discharge; 9365 hadn’t been prescribed these drugs. Their average age was 64 and around 1 in 4 were women.

The researchers wanted to find out if there were any differences between the two groups in terms of deaths from any cause and rates of further heart attacks, revascularisation, or hospitalisation for heart failure.

The real time data showed that long term treatment with beta blockers wasn’t associated with improved cardiovascular outcomes during an average monitoring period of 4.5 years.

Some 6475 (19%) of those on beta blockers, and 2028 (22%) of those who weren’t, died from any cause, or had another heart attack, or required unscheduled revascularisation, or were admitted to hospital for heart failure.

After accounting for potentially influential factors, including demographics and relevant co-existing conditions, no significant difference was seen in rates of these events between the two groups.

As an observational study, it can’t establish cause. Additionally, despite being the largest study of its kind to date, the findings should be viewed in the context of certain limitations, acknowledge the researchers.

Patients weren’t randomised to treatment; only certain cardiovascular outcomes were included; there was no indication of how consistently patients took their drugs; nor any information on their health related quality of life.

And there were some differences between the two groups in respect of factors known to influence the risk of poor cardiovascular outcomes.

But, the researchers point out, beta blockers are associated with several side effects such as depression and fatigue, and it’s now time to reassess the value of long term treatment with these drugs in heart attack patients who don’t have heart failure or LVSD, they suggest.

In a linked editorial, Professor Ralph Stewart and Dr Tom Evans write: “Despite strong evidence that long-term beta-blockers can improve outcomes after [heart attack], it has been uncertain whether this benefit applies to lower risk patients who are taking other evidence-based therapies and who have a [normal functioning heart].”

They point out: “Recommendations on the duration of beta blocker therapy are variable or absent because this question was not specifically evaluated in clinical trials. Most patients take daily medications for many years after a [heart attack] because they believe they are beneficial.”

And they conclude: “[This] study raises an important question directly relevant to the quality of care –do patients with a normal [functioning heart] benefit from long term beta-blocker therapy after [heart attack]? To answer this question, more evidence from large randomised clinical trials is needed.”

Source: EurekAlert!

Categories : Cardiovascular Disease Medical Industry Metabolic DisordersTags :

Bempedoic Acid Could be a Viable Alternative to Statins

On By ModernMedia
Photo by Towfiqu Barbhuiya on Unsplash

Bempedoic acid, a new cholesterol-lowering drug, has the potential to be an effective substitute for patients who can’t tolerate statins. Bempedoic acid is an ATP citrate lyase inhibitor that reduces low-density lipoprotein (LDL) cholesterol levels and is associated with a low incidence of muscle-related adverse events. Its effects on cardiovascular outcomes were uncertain, so researchers used a double-blind, randomised, placebo-controlled trial to determine outcomes on a variety of cardiovascular measures in statins-intolerant patients.

The study, published in the New England Journal of Medicine, recruited patients aged 18–85 years at increased cardiovascular risk and unable or unwilling to take statins due to adverse effects. Patients were first tested with placebo over a 4-week run-in period, and were not randomised if they experience unacceptable adverse effects or if adherence was less than 80%. The 13 970 patients who successfully completed run-in were randomised to receive bempedoic acid 180mg orally per day or matching placebo. 

The mean LDL cholesterol level at baseline was 139.0mg/dL in both groups, and after 6 months, the reduction in the level was greater with bempedoic acid than with placebo by 29.2mg/dL; the observed difference in the percent reductions was 21.1 percentage points in favour of bempedoic acid.

Compared to placebo, risk of fatal or nonfatal stroke, death from cardiovascular causes, and death from any cause after significantly were lower by 13%, after a median of 40.6 months of follow-up. The risk of death from cardiovascular causes, nonfatal stroke, or nonfatal myocardial infarction was 15% lower with bempedoic acid than with placebo, and the risks of fatal or nonfatal myocardial infarction and coronary revascularisation were 23% lower and 19% lower, respectively.

The researchers noted that the LDL-cholesterol lowering effects were similar in magnitude and predicted reduction in cardiovascular risks to that observed with statins. In addition, bempedoic acid did not increase glycated haemoglobin levels or the incidence of new-onset diabetes, unlike statins. Due to the demonstrated benefits, those taking placebo were offered the chance to transition to taking bempedoic acid.

A trial limitation was that it only included patients with statins intolerance, and who therefore had higher LDL cholesterol levels at baseline.

Categories : Cardiovascular DiseaseTags :

Iron Drives Chronic Heart Failure in Myocardial Infarction Survivors

On By ModernMedia
Photo by Freestocksorg on Pexels

A multi-institution study has found that iron drives the formation of fatty tissue in the heart and leads to chronic heart failure in about 50% of myocardial infarction (MI) survivors. The discovery, recently published in Nature Communications, paves the way for treatments that have the potential to prevent heart failure.

“For the first time, we have identified a root cause of chronic heart failure following a heart attack,” said study leader Rohan Dharmakumar, PhD, of Indiana University School of Medicine.

“While advances across populations have made survival after a heart attack possible for most, too many survivors suffer long-term complications like heart failure,” said Subha Raman, MD, who is physician director of the Cardiovascular Institute. “Dr. Dharmakumar’s breakthrough science illuminates who is at risk and why and points to an effective way to prevent these complications.”

The study followed large animal models over six months. In MI with bleeding complications, scar tissue is slowly replaced by fat. Fatty tissue can’t push blood from the heart effectively, and this is what leads to heart failure and eventually to death in many survivors of haemorrhagic MI, Dharmakumar said.

“Using noninvasive imaging, histology and molecular biology techniques, and various other technologies, we have shown that iron from red blood cells is what drives this process,” he explained. “When we removed the iron, we reduced the amount of fat in the heart muscle. This finding establishes a pathway for clinical investigations to remedy or mitigate the effects associated with iron in haemorrhagic myocardial infarction patients.”

Dharmakumar’s team is currently testing iron chelation therapy to do just that in a just-launched clinical trial.

“Thanks to a clinical trial underway being led by his team at Indiana University, I’m excited to see this treatment improve the lives of millions of heart attack survivors worldwide,” said Raman.

Source: Indiana University School of Medicine

Categories : Cardiovascular Disease Surgeries & ProceduresTags :

Troponin Levels Help Inform When to Perform Surgery after Heart Attack

On By ModernMedia
Photo by Natanael Melchor on Unsplash

New research from a large study published in the International Journal of Cardiology shows that timing of surgery for some heart attack patients can be improved by analysing troponin levels.

Troponin is a protein involved in muscle contraction that is released into the bloodstream after heart attack, with higher levels indicating more heart damage. Troponin levels help clinicians to determine whether a patient is having a heart attack, or myocardial infarction (MI), and to decide on treatment options such as coronary artery bypass graft (CABG) surgery.

The optimal time to perform surgery following an MI remains unclear. Previous reports have suggested that carrying out surgery in the first few days following an MI is associated with a higher risk of surgical complications and death by not leaving time for the heart to recover. As a result, following an MI, many patients who need bypass surgery wait for more than 10 days before surgery is performed.

Researchers in this study found that some patients who have lower levels of troponin would benefit from having earlier surgery. However, the researchers show that patients with very high troponin levels should have surgery postponed, as their risk of dying was higher if surgery was performed within 10 days of their MI.

There was no benefit in delaying surgery for those with low levels of troponin, according to the study.

Early surgery for MI patients

The researchers suggest that early surgery for MI patients with lower troponin levels would reduce overall length of stay and ease pressure on resources such as staff.

This is the first multicentre study to investigate the interaction between the extent of heart damage, as indicated by troponin levels, and the optimal time to wait for surgery in a large series of MI patients. 

Dr Amit Kaura, lead author of the research, said: “The approach on the safest time to operate on patients following a heart attack varies in hospitals across the UK. Our study could help clinicians make more informed decisions on the best treatment plans for heart attack patients requiring surgery, based on their levels of troponin. It could also lead to a more standardised approach in the NHS on how we treat this patient group, leading to resources being used effectively, shorter stays and improved outcomes for patients.”

The study reviewed patients who had a non-ST segment elevation myocardial infarction (NSTEMI) due to a blockage to their coronary arteries who required a CABG.

About 20% of NSTEMI patients have a CABG. The optimal timing for CABG surgery in patients with uncomplicated NSTEMI has been unclear. Prior to the new research, some studies had suggested that early surgery was associated with higher mortality post operation. This has led to a tendency for CABG to be delayed if a patient’s condition remains stable. However, other studies had reported similar mortality rates after early versus late surgery, concluding that delaying surgery in all patients after uncomplicated NSTEMI is not warranted and does not improve outcomes. No previous study had investigated in a large group of patients whether there was an association between the extent of heart damage (as measured by troponin levels) and the wait for surgery on survival.

Heart data insights

The team analysed data from the NIHR HIC of 1746 patients with NSTEMI and unstable angina (UA) where insufficient cardiac blood supply leads to an MI. The cohort consisted of 1684 patients with NSTEMI and 62 with UA. The average age of the group was 69 and 21% were female. They underwent CABG within 90 days at one of five cardiac centres before their surgery between 2010 and 2017. 

The researchers compared patients’ troponin levels, wait between surgery and outcomes after surgery within the first 30 days and over a period of five years. Pre-operative troponin level strongly predicted early mortality, and this was significantly influenced by the interval to surgery. The average wait for patients with high troponin levels to surgery was nine days. Sixty patients died within 30 days after surgery and another 211 patients died over a period of five years following surgery. They found that for those who had troponin levels of less than 100 times the normal upper limit, delaying surgery to after 10 days was not associated with lower survival. For patients with higher troponin levels, early survival increased progressively with a longer time to surgery – survival was highest in those who had surgery after day 10. 

Dr Amit Kaura said: “For patients with troponin levels of under 100 times the normal upper limit, extending the waiting time or surgery did not improve early survival. This finding is particularly significant as two-thirds of patients presenting with troponin levels of under 100 are waiting on average 12 days for surgery after being admitted to hospital. There are potential cost saving implications with our research by performing earlier surgery in this group of patients with lower troponin levels”.

The effect of troponin levels pre-operation on survival was limited to the first 30 days after surgery. Late survival was determined by other risk factors, such as age and other co-morbidities such as hypertension.

Further studies are needed in the form of prospective trials to assess the impact of troponin and timing of surgery on survival following a heart attack, the researchers say.

Source: Imperial College London

Categories : Cardiovascular Disease HIVTags :

People with HIV and Hepatitis C Have Increased Heart Attack Risk

On By ModernMedia
Source: Wikimedia Commons CC0

As people with HIV age, their risk of myocardial infarction increases far more if they also have untreated hepatitis C virus, according to new research published today in the Journal of the American Heart Association.

According to the findings, even with antiretroviral therapy (ART), the risk of myocardial infarction (MI) among people with HIV is at least 50% higher than people without HIV. This new study evaluated if people with HIV who also have hepatitis C have a higher risk of MI.

“HIV and hepatitis C coinfection occurs because they share a transmission route – both viruses may be transmitted through blood-to-blood contact,” said Associate Professor Keri N. Althoff, PhD, MPH, senior author of the study. “Due in part to the inflammation from the chronic immune activation of two viral infections, we hypothesised that people with HIV and hepatitis C would have a higher risk of heart attack as they aged compared to those with HIV alone.”

Researchers analysed health information for 23 361 people with HIV in the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) between 2000–2017 started on antiretroviral treatment for HIV, median age 45 at enrolment. One in 5 study participants (4677) were also positive for hepatitis C. During a median follow-up of about 4 years, the researchers compared the occurrence of a heart attack between the HIV-only and the HIV-hepatitis C co-infected groups as a whole, and by each decade of age.

The analysis found:

  • With each decade of increasing age, MI incidence increased 30% in people with HIV alone and 85% in those who were also positive for hepatitis C.
  • The risk of heart attack increased in participants who also had traditional heart disease risk factors such as high blood pressure (more than 3 times), smoking (90%) and Type 2 diabetes (46%).
  • The risk of heart attack was also higher (40%) in participants with certain HIV-related factors such as low levels of CD4 immune cells (200 cells/mm3, signalling greater immune dysfunction) and 45% in those who took protease inhibitors (one type of ART linked to metabolic conditions).

“People who are living with HIV or hepatitis C should ask their doctor about treatment options for the viruses and other ways to reduce their cardiovascular disease risk,” said Assistant Professor Raynell Lang, MD, MSc, lead study author.

“Several mechanisms may be involved in the increased heart attack risk among co-infected patients. One contributing factor may be the inflammation associated with having two chronic viral infections,” A/Prof Lang said. “There also may be differences in risk factors for cardiovascular disease and non-medical factors that influence health among people with HIV and hepatitis C that plays a role in the increased risk.”

“Our findings suggest that HIV and hepatitis C co-infections need more research, which may inform future treatment guidelines and standards of care,” Althoff said.

The study is limited by not having information on additional factors associated with heart attack risk such as diet, exercise or family history of chronic health conditions. Results from this study of people with HIV receiving care in North America may not be generalizable to people with HIV elsewhere. In addition, the study period included time prior to the availability of more advanced hepatitis C treatments.

“Because effective and well-tolerated hepatitis C therapy was not available during several years of our study period, we were unable to evaluate the association of treated hepatitis C infection on cardiovascular risk among people with HIV. This will be an important question to answer in future studies,” Lang said.

Source: American Heart Association