Arteries are blood vessels that carry oxygen and nutrient-rich blood from the heart to the rest of our body, while veins return ‘spent’ blood (high in waste products and carbon dioxide) to the heart. Atherosclerosis in Singapore is a vascular disease that affects arteries and hence blood supply in our body. The term atherosclerosis has Greek origins; athèrè (gruel or porridge) and sclerosis (hardening). Arteries have three distinct layers to their wall, from inner to outer they comprise intima, media, and adventitia. In atherosclerosis, high levels of cholesterol and triglycerides in the blood lead to abnormal deposition of these fatty substances within the intima and media layers. This incites repeated inflammatory reactions that cause calcium to form (calcification) and plaques to build. With time, there is hardening of the arterial wall and bulky plaques can narrow the flow channel (lumen) of the artery, causing reduced blood supply and threatening the lifeline distally. Atherosclerosis in Singapore can affect any vascular bed and hence can threaten any organ system, giving rise to varied symptoms and problems.
The carotid and cerebral arteries are the main blood supply to our head, neck, and brain. Carotid artery stenosis (narrowing) from atherosclerosis can lead to turbulent flow and the formation of small clots, which travel into the cerebral circulation and the brain. These clots can acutely cut off the blood supply in the arterial branch that it gets wedged into, resulting in a stroke. Patients can present with facial droop, weakness or paralysis in their arms or legs, difficulty talking or understanding, and even loss of consciousness. Vascular specialists can treat carotid artery disease with carotid endarterectomy to remove the plaque or carotid artery stenting to widen the narrowing through endovascular (minimally invasive) techniques.
Coronary arterial disease occurs when atherosclerosis in Singapore affects the blood supply to the heart organ. Reduction of blood flow to the heart muscle (myocardium) can lead to chest pain (angina pectoris), especially upon exertion. The pain is characteristically central in nature and can radiate upwards to the jaw and commonly into the left arm. Some will experience upper abdominal discomfort while others can be silent (pain-free). Atherosclerotic plaques can be unstable and rupture, releasing fatty material when the intima wall layer is breached. This denuded surface that is in contact with blood steam is prone to clot formation and can lead to complete occlusion of that coronary artery (acute coronary syndrome) where a massive heart attack can ensue with resultant cardiac arrest. Chronic damage from poor blood supply to the myocardium can also affect the electrical conduction system (Purkinje fibers) of the heart, leading to rhythm problems with resultant heart failure or clot (thrombus) formation within the heart chambers that can be ejected into arterial branches of vital organs in the body.
Chronic Mesenteric Ischemia (CMI) occurs when atherosclerosis narrows the main blood supply to our gastrointestinal (digestive) organs. Patients complain of severe abdominal pain after meals, develop food fear, and experience weight loss over time. Vascular specialists can treat CMI with open vascular bypass or endovascular stenting. Acute Mesenteric Ischemia (AMI) is a surgical emergency where the blood supply to a part of the intestines is cut off and there is segmental necrosis (death). Patients complain of severe abdominal pain that does not get better. Vascular specialists treat AMI with intestinal resection and re-establishing blood flow to the mesenteric artery by clot removal, vascular bypass, or endovascular stenting.
Renal arteries supply the kidneys and renal artery disease (RAD) due to atherosclerosis can cause paradoxical high blood pressure (hypertension) despite reduced blood flows to the kidneys. Reduced blood flow in RAD causes the kidney organs to activate the renin-angiotensin-system to elevate blood pressure in an attempt to increase blood flow to the kidneys. Hypertension due to RAD is typically more resistant to medical therapy and can lead to medical emergencies such as pulmonary edema (water-logged lungs and inability to breathe), hypertensive urgency (sudden severe hypertension with risk of heart attack or stroke), and acute renal failure. Vascular specialist can treat RAD with open surgery or minimally invasive endovascular stenting.
Peripheral Arterial Disease (PAD) affects arteries of the lower extremities, reducing blood flow to impair walking ability, or if severe (chronic limb-threatening ischemia/CLTI) – can lead to amputation and limb loss. In mild/moderate PAD, patients experience cramps in the leg, thigh, or buttock muscles upon walking (intermittent claudication) or climbing stairs. The more severe the narrowings in the arteries, the shorter the distance they can manage, and the longer it takes for the cramping pain to go away. Starting a Supervised Walking Exercise Program with our vascular specialists can significantly improve the patient’s walking ability, as more collateral vessels develop to compensate for the reduced blood supply. In severe CLTI, patients can present with pain at rest without exertion (also known as rest pain) or tissue loss (spontaneous wounds or ulcers, or gangrene). CLTI has a high risk of limb loss if not treated in a timely manner, of which up to 20% – 40% of patients end up with amputations. Vascular specialists can treat CLTI with revascularization procedures to bring more blood flow to the limb, by open vascular bypass surgery or endovascular therapy such as balloon angioplasty and stenting.
Vascular specialists at PanAsia Surgery treat atherosclerosis in a holistic manner, as it is a systemic disease not isolated to one vascular bed or organ. Counseling is provided to better understand the condition and to formulate the best treatment plan for each patient, identifying the factors that can be improved upon. Factors and risk factors that cannot be changed include age, gender (more severe in men), family history, genetic conditions, and ethnicity. Factors that can be modified include a healthy lifestyle and diet, regular exercise, avoiding obesity, compliance and effective management of confounding conditions like diabetes, hypertension, and hypercholesterolemia, smoking cessation, and moderation of alcohol intake. Additionally, patients who require more targeted revascularization treatment to improve blood supply and flow can be offered vascular surgery or endovascular therapy.