Cardiovascular diseases claim the lives of 17.9 million people every year, 31 per cent of all global deaths, according to recent research from the World Health Organization (WHO). Reports have found that in the U.S., the average age for a first heart attack in men is 65. And while coronary artery disease is labelled as an ailment affecting older people, reportedly as many as four to 10 per cent of all heart attacks occur before age 45, and it mostly affects men. In the Middle East too, cardiovascular disease (CVD) remains one of the leading causes of fatality. In 2015, CVD was responsible for 34 per cent of all deaths in the Middle Eastern region.
What causes heart disease?
Cardiovascular diseases are triggered by tobacco and alcohol use, unhealthy diet and physical inactivity, leading to obesity, which can raise blood pressure and elevate blood glucose, which are all detrimental to good heart health. Also, age-related changes to the heart can cause faulty heart valves, one of the common causes of CVD. Diseases such as atherosclerosis (building up of plaque inside arteries) start in youth and, therefore, warning signs should not be ignored, and prevention should start early in life.
Reportedly, nearly all heart attacks in older men are caused by atherosclerotic blockages in coronary arteries. Coronary artery disease (CAD) accounts for almost 80 per cent of heart attacks, while 60 per cent of patients are found to have the disease of one coronary artery, while older patients are more likely to have the disease in two or more arteries. Other causes of heart attacks can be attributed to blood clots, spasm or inflammation of the coronary arteries, radiation therapy for chest tumours, chest trauma, and abuse of drugs.
Valvular heart diseases (VHD) are among the major causes of acute and chronic heart failure. Factors such as aortic stenosis (AS) and mitral regurgitation (MR) are some of the most prevalent aetiologies of severe native VHD, which is associated with congestive heart failure. Due to this, indications for left-sided percutaneous interventions have increased, which allows treating patients who had previously not been deemed suitable for surgery.
Percutaneous interventions offer the benefits of a minimally invasive approach and have reportedly shown better results in patients who are suitable for open-heart surgery too.
An alternative approach to open-heart surgery
One method that has received noteworthy results is Transcatheter Aortic Valve Implantation (TAVI) and is mainly used to correct aortic stenosis, sometimes with aortic regurgitation – conditions that account for 75 per cent of all patients with valve disease. TAVI is also less traumatic than open-heart surgery, especially for patients with existing comorbidities.
A European Society of Cardiology report highlighted that over the last 15 years, there has been a rapid uptake of TAVI. This has been coupled with the advancement in transcatheter valve technologies and the new devices provide benefits such as smaller delivery systems, less incidence of paravalvular leak (PVL) or need for permanent pacemaker implantation (PPI).
In an interview with Omnia Health Insights, Dr Simon Davies, consultant interventional cardiologist at the Royal Brompton & Harefield Hospitals Specialist Care, explained that the aortic valve is one of four valves in the heart and is the outlet valve from the main pumping chamber. It controls the blood flowing out of the heart and around the body with thin leaflets of tissue that open and close when the heart beats to regulate blood flow.
“Aortic stenosis is the most common and serious form of valve disease,” he said. “The condition causes the leaflets to stiffen so that the valve does not open properly, and this narrowing of the valve makes it harder for the heart to pump blood to the body. This causes symptoms including shortness of breath, heart murmur, fainting and fatigue.”
How TAVI works
During the procedure, a catheter is guided through an artery to the heart using imaging equipment, then a new valve placed within the narrowed aortic valve and expanded to relieve the obstruction there.
Dr Davies said: “Imaging is a very important part of the process. The combination of a very low dose X-ray and, where necessary, an echocardiogram, helps to guide the device into position and checks it is working properly. One week before the procedure high-quality computed tomography (CT) scans are taken to provide images of the patient’s aortic valve. This identifies the right size and type of replacement valve.”
What problem does it solve? It corrects a narrowed valve which makes the heart’s work pumping blood around the body harder and which otherwise causes symptoms such as breathlessness, heart murmur, chest pain and fainting.
“Recent clinical trials showed TAVI is as good as conventional surgery in those people. It is being offered more routinely to people in their late 60s and early 70s without other health problems. Patients with failing surgical valves made from tissue, which degenerate in years, are also excellent candidates for TAVI, as younger people would otherwise need several open-heart surgeries in their lifetimes,” he added.
In a recent paper, the Journal of the Saudi Heart Association highlighted that the use of general anaesthesia for the TAVI procedure ensures patient stability. However, a few studies have demonstrated the feasibility of TAVI with the patient under local anaesthesia with conscious sedation. This has the advantage of being less invasive, a shorter procedure time, a shorter intensive care unit stay, an earlier recovery, and a shorter hospital stay.
Local anaesthesia with conscious sedation may be considered as the best anaesthesia technique during the COVID-19 crisis provided that the patient is not in decompensated heart failure, can lie flat in the bed, and not morbidly obese, the paper stressed. However, the anaesthesia team should be prepared to use general anaesthesia at any time during the procedure. This approach is particularly crucial at this crisis, where the majority of TAVI patients will not utilise the intensive care unit for their recovery after the procedure, and this is important as critical care beds will be limited during the COVID-19 crisis in many countries.
Impact of COVID-19 on VHD
The COVID-19 pandemic has caused an unprecedented burden on healthcare resources, which has impacted the treatment of heart failure and VHD. The risk of in-hospital infection and reduced access to hospitals has caused a delay in VHD treatment. Also, most non-urgent surgical or percutaneous procedures for VHD were postponed and most patients cancelled procedures on their own due to fears of them or their families contracting COVID-19.
According to the Journal of the Saudi Heart Association, while COVID-19 is primarily a respiratory infection, it has significant systemic effects, including in the cardiovascular system. Cardiac manifestations of COVID-19 infection including all types of myocardial injury, and arrhythmias have already been reported with COVID-19 disease. Patients with pre-existing cardiovascular conditions represent significant proportions of patients with symptomatic infection and experience disproportionately worse outcomes.
In a recent paper, the European Society of Cardiology stressed that reorganisation of healthcare resources is the need of the hour, including implementing a proper algorithm for patients’ prioritisation, based on the severity of their valve disease, life expectancy, the complexity of the intervention, and the resources available. Moreover, wider use of telemedicine for patients’ selection and follow-up and any measurement that can shorten the duration of the hospital stay must be adopted. Percutaneous procedures, compared to surgery, are associated with a lower risk of infection and a lesser need for in-hospital resources, including a shorter duration of hospital stay and this could favour their adoption when the risk of viral infection is high.
For patients at high risk of admission, the NHS guidance suggests they be considered on a case-by-case basis and that current pathways should be followed where possible. If this is not possible due to a shortage of ICU beds or other constraints, TAVI can be considered as an alternative to surgery in aortic stenosis.
According to the European Society of Cardiology, increased use of TAVI, when feasible, may allow optimal utilisation, of resources by avoiding general anaesthesia and intubation, shortening or preventing stay and accelerating hospital discharge and recovery.
References available on request
Article sponsored by Edwards Lifesciences