any of this sound possibly relevant?
Magnesium and Vascular Changes in Hypertension (2012)http://www.ncbi.nlm.nih.gov/pubmed/22518291
Many factors have been implicated in the pathogenesis of hypertension, including changes in intracellular concentrations of calcium, sodium, potassium, and magnesium. There is a significant inverse correlation between serum magnesium and incidence of cardiovascular diseases. Magnesium is a mineral with important functions in the body such as antiarrhythmic effect, actions in vascular tone, contractility, glucose metabolism, and insulin homeostasis. In addition, lower concentrations of magnesium are associated with oxidative stress, proinflammatory state, endothelial dysfunction, platelet aggregation, insulin resistance, and hyperglycemia. The conflicting results of studies evaluating the effects of magnesium supplements on blood pressure and other cardiovascular outcomes indicate that the action of magnesium in the vascular system is present but not yet established. Therefore, this mineral supplementation is not indicated as part of antihypertensive treatment, and further studies are needed to better clarify the role of magnesium in the prevention and treatment of cardiovascular diseases.
Blood pressure and serum potassium levels in hypertensive patients receiving or not receiving antihypertensive treatment. (2007)http://www.ncbi.nlm.nih.gov/pubmed/18058481
RESULTS: After adjusting for age, gender, and body mass index, significant negative correlations were found between serum potassium levels and systolic BP (R = -0.093, p = 0.007), diastolic BP (R = -0.078, p = 0.03), mean BP (R = -0.122, p = 0.002), and pulse pressure (R = -0.071, p = 0.044). The levels of potassium were found to be significantly lower among patients receiving diuretics than those receiving one of the other four drug categories of antihypertensive (p < 0.05 for beta-blockers, ACE inhibitors, and CCBs; p < 0.001 for ARBs). In addition, hypokalemia was found to be significantly more prevalent in the group using diuretics than the other groups.
CONCLUSIONS: The observed reverse relation between serum potassium and BP supports a close pathophysiological connection between serum potassium and essential hypertension. Moreover, diuretic therapy is a significant cause of hypokalemia and requires systematic monitoring.
i have had to deal with shortness of breath, inability to complete a proper deep breath, among other things.. issues resolved after magnesium tested in bottom end of normal range and i optimized serum levels to above 0.90 mmol/L.