Calcium phosphate (hydroxyapatite) deposits in the muscular layer of the blood vessels appear to play a significant role in stiffening the arteries and inducing the early phase of coronary arteriosclerosis. This can be seen in a so-called metastatic mechanism of calciphylaxis as it occurs in chronic kidney disease and hemodialysis. Although these people have kidney dysfunction, almost fifty percent of them die due to coronary artery disease. Plaques can be thought of as large "pimples" that protrude into the channel of an artery, causing partial obstruction to blood flow. People with coronary artery disease might have just one or two plaques, or might have dozens distributed throughout their coronary arteries. A more severe form is chronic total occlusion (CTO) when a coronary artery is completely obstructed for more than 3 months.Cardiac syndrome X is chest pain (angina pectoris) and chest discomfort in people who do not show signs of blockages in the larger coronary arteries of their hearts when an angiogram (coronary angiogram) is being performed. The exact cause of cardiac syndrome X is unknown. Explanations include microvascular dysfunction or epicardial atherosclerosis. For reasons that are not well understood, women are more likely than men to have it; however, hormones and other risk factors unique to women may play a role. Diagnosis
For symptomatic people, stress echocardiography can be used to make a diagnosis for obstructive coronary artery disease.
The impairment of Na transport in the distal convoluted tubule induces natriuresis and water loss, while increasing the reabsorption of calcium in this segment in a manner unrelated to sodium transport. Amiloride also increases distal tubular calcium reabsorption and has been used as a therapy for idiopathic hypercalciuria. A combination of 25 mg of chlorthalidone plus 5 mg of amiloride daily led to a substantial reduction in urine calcium in Dents patients, but urine pH was "significantly higher in patients with Dent’s disease than in those with idiopathic hypercalciuria (P < 0.03), and supersaturation for uric acid was consequently lower (P < 0.03)." For patients with osteomalacia, vitamin D or derivatives have been employed, apparently with success. Some lab tests on mice with CLC-5-related tubular damage showed a high-citrate diet preserved kidney function and delayed progress of kidney disease. History
Dents disease was first described by Charles Enrique Dent and M. Friedman in 1964, when they reported two unrelated British boys with rickets associated with renal tubular damage characterized by hypercalciuria, hyperphosphaturia, proteinuria, and aminoaciduria. This set of symptoms was not given a name until 30 years later, when the nephrologist Oliver Wrong more fully described the disease. Wrong had studied with Dent and chose to name the disease after his mentor. Dents disease is a genetic disorder caused by mutations in the gene CLCN5, which encodes a kidney-specific voltage-gated chloride channel, a 746-amino-acid protein (CLC-5) with 12 to 13 transmembrane domains. It manifests itself through low-molecular-weight proteinuria, hypercalciuria, aminoaciduria and hypophosphataemia.