Ischemic heart disease arrhythmia

Hypokalemia and hypomagnesemia may cause muscle fatigue or cramps. Serious cardiac arrhythmias may occur, especially in patients receiving digitalis therapy, patients with LV hypertrophy, and those with ischemic heart disease. Low-dose therapy (e.g., 25 mg hydrochlorothiazide or 12.5 mg chlorthalidone daily) rarely causes significant electrolyte disturbances. 

Angina, arrhythmias, congestive heart failure, ischemic heart disease, myocardial infarction Endocrine and metabolic... 

The [ -adrenoreceptors antagonists (also called [)-blockers) comprise a group of chiral drugs that are mostly used in the treatment of cardiovascular disorders such as hypertension, cardiac arrhythmia, or ischemic heart disease. Teicoplanin is the chiral selector most exploited for the enantioseparation of this class of compounds, followed by vancomycin. Several P-blockers have been analyzed, particularly in the... 

They are used for arrhythmias associated with nervous stress, myocardial infarction, and thyrotoxicosis accompanied by elevated adrenergic activity. Moreover, many antiarrhythmic drugs themselves can cause arrhythmia, especially in patients with ischemic heart disease. The examined 8-adrenergic receptor blockers are an exception. Having said that, practically all )3-adrenergic receptor blockers can be used as antiarrhythmics. 

Cardiovascular effects Use with caution in patients with cardiovascular disorders including coronary insufficiency, ischemic heart disease, history of stroke, coronary artery disease, cardiac arrhythmias, CHF, and hypertension. 

Ephedrine may cause hypertension resulting in intracranial hemorrhage. It may induce anginal pain in patients with coronary insufficiency or ischemic heart disease. Large doses of inhaled or oral salmeterol (12 to 20 times the recommended dose) have been associated with clinically significant prolongation of the QTc interval, which has the potential for producing ventricular arrhythmias. 

Most of the indications for -blockers concern the -adrenoceptor. This subtype is predominantly present in the heart, mediating all typical cardiac effects like positive inotropy, chronotropy and dro-motropy. The main indications are hypertension, ischemic heart disease, cardiac arrhythmias and some forms of congestive heart failure. The mechanism by which -blocker, when administered chronically, can reduce the blood pressure is not completely understood yet. Most probably several mechanisms. 

In patients with longstanding hypothyroidism and those with ischemic heart disease, rapid correction of hypothyroidism may precipitate angina, cardiac arrhythmias, or other adverse effects. For these patients, replacement therapy should be started at low initial doses, followed by slow titration to full replacement as tolerated over several months. If hypothyroidism and some degree of adrenal insufficiency coexist, an appropriate adjustment of the corticosteroid replacement must be initiated prior to thyroid hormone replacement therapy. This prevents acute adrenocortical insufficiency that could otherwise arise from a thyroid hormone-induced increase in the metabolic clearance rate of adrenocortical hormones. 

Contraindications Cardiac arrhythmias, cerebrovascular insufficiency, hypertension, hyperthyroidism, ischemic heart disease, narrow-angle glaucoma, shock... 

Restlessness, anxiety, tremor, headache. Both adrenaline and noradrenaline cause sudden increase in blood pressure, precipitating sub-arachnoid haemorrhage and occasionally hemiplegia, and ventricular arrhythmias. May produce anginal pain in patients with ischemic heart disease. 

Adverse effects Thiazide diuretics induce hypokalemia and hyperuricemia in 70% of patients, and hyperglycemia in 10% of patients. Serum potassium levels should be monitored closely in patients who are predisposed to cardiac arrhythmias (particularly individuals with left ventricular hypertrophy, ischemic heart disease, or chronic congestive heart failure) and who are concurrently being treated with both thiazide diuretics and digitalis glycosides (see p. 160). Diuretics should be avoided in the treatment of hypertensive diabetics or patients with hyperlipidemia. 

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