Is it ok to have Vitamin D levels just above the lower limit of normal? 

It depends! If you are just above the lower limit of normal and it is the start of the winter then I would be looking to optimise your level by taking a supplement as it is likely to drop further without strong sunlight exposure. If it is at the start of the summer months or you are expecting to go on a sunshine holiday and you will be spending lots of time outside then you will probably make enough vitamin D to optimise your levels. If for whatever reason you spend most of your time indoors or your skin is sensitive to the sun then you would be wise to continue a supplement of vitamin D all year round.  Don’t forget that vitamin D is fat soluble and best taken with a meal containing some fat so it will be better absorbed.

What are the main symptoms of B12 Vitamin deficiency? 

Vitamin B12 deficiency can affect every body system potentially. It is more common in vegetarians and vegans as it is mostly available from animal sources but also common in people taking certain medications which reduce its absorption from the stomach and anyone with malabsorption disorders such as coeliac disease or after gastric bypass surgery.  I see patients presenting with all sorts of neurological symptoms like tingling, headaches, tremor, memory problems, dizziness, tinnitus, anxiety, depression and fatigue is very common.

What are the main symptoms of Vitamin D deficiency?

The common symptoms I find in general practice are musculoskeletal pains. But vitamin D is involved in so many other body processes, not just bone and muscle health. It has roles in the immune system, in blood sugar regulation, cancer prevention, it helps to reduce inflammation and is important in mental illness too. It is a factor in the development of osteoporosis and rickets in children if it is persistently very low. 

Why does angina cause fatigue? 

Angina by definition is a transient Ischaemic  episodes not leading to  cellular death. As  such it should not cause chronic fatigue. However, during an anginal episode, if the ischaemic territory is large enough or if critical component of the heart are involved (e.g. Papillary muscles and mitral valve), then it may be associated with fatigue and/or shortness of breath

Can you describe the relationship between CAS, CMVD and Endothelial Dysfunction?

Myocardial ischaemia has been traditionally perceived as the consequence of atherosclerotic obstructions of the coronary vessels. More recently an overwhelming body of evidence has proven that atherosclerotic obstructions are just one of several mechanisms that can precipitate myocardial ischaemia. CAS, CMVD and Endothelial Dysfunction are included among the mechanisms that, in isolated fashion or in combination, may cause myocardial ischaemia

What is the difference between Endothelium Dependent CMD and non Endothelium Dependent CMD?

The wall of the blood vessel (coronary artery) supplying the heart muscle has got three layers: the innermost layer contains endothelial cells, the middle layer contains the smooth muscle cells and the outermost layer contains collagen fibres for support.

The endothelial cells naturally release a substance called nitric oxide (NO), that then diffuses along into the neighbouring smooth muscle cells and causes these cells to relax. This leads to the coronary artery dilating, which results in an increased blood flow to the heart muscle. This is an important physiological response to exertion.

Endothelium-dependent CMD essentially means an inability of the endothelial cells to produce nitric oxide. As a result, the smooth muscle cells are unable to relax and the coronary artery is unable to dilate as required. This results in blunted increase in blood flow to the heart muscle during times of stress, which results in angina.

Endothelium-independent (or non-endothelium dependent) CMD refers to an inability of the smooth muscle cells to relax despite an adequate amount of nitric oxide. This, again, results in blunted increase in blood flow to the heart muscle during times of stress, which results in angina.

Therefore, both group of patients have an inability to dilate their coronary arteries in response to stress, which reduces the blood flow to the heart muscle during times of stress, leading to angina

What is the difference between Endothelium Dependent CMD and non Endothelium Dependent CMD?

The wall of the blood vessel (coronary artery) supplying the heart muscle has got three layers: the innermost layer contains endothelial cells, the middle layer contains the smooth muscle cells and the outermost layer contains collagen fibres for support.

The endothelial cells naturally release a substance called nitric oxide (NO), that then diffuses along into the neighbouring smooth muscle cells and causes these cells to relax. This leads to the coronary artery dilating, which results in an increased blood flow to the heart muscle. This is an important physiological response to exertion.

Endothelium-dependent CMD essentially means an inability of the endothelial cells to produce nitric oxide. As a result, the smooth muscle cells are unable to relax and the coronary artery is unable to dilate as required. This results in blunted increase in blood flow to the heart muscle during times of stress, which results in angina.

Endothelium-independent (or non-endothelium dependent) CMD refers to an inability of the smooth muscle cells to relax despite an adequate amount of nitric oxide. This, again, results in blunted increase in blood flow to the heart muscle during times of stress, which results in angina.

Therefore, both group of patients have an inability to dilate their coronary arteries in response to stress, which reduces the blood flow to the heart muscle during times of stress, leading to angina