Myocardial insufficiency

When the hydantoins are used with odier CNS depressants (eg, alcohol, narcotic analgesics, and antidepressants), an additive CNS depressant effect may occur. The hydantoins are used cautiously in patients widi liver or kidney disease and neurologic disorders. Phenytoin is used cautiously in patients widi hypotension, severe myocardial insufficiency, and hepatic impairment. 

Congestive heart failure In myocardial insufficiency, the heart depends on a tonic sympathetic drive to maintain adequate cardiac output. Sympathetic activation gives rise to an increase in heart rate and systolic muscle tension, enabling cardiac output to be restored to a level comparable to that in a healthy subject. When sympathetic drive is eliminated during p-receptor blockade, stroke volume and cardiac rate decline, a latent myocardial insufficiency is unmasked, and overt insufficiency is exacerbated (A). 

Indications. Verapamil is used as an antiarrhythmic drug in supraventricular tachyarrhythmias. In atrial flutter or fibrillation, it is effective in reducing ventricular rate by virtue of inhibiting AV-conduction. Verapamil is also employed in the prophylaxis of angina pectoris attacks (p. 308) and the treatment of hypertension (p. 312). Adverse effects Because of verapamil s effects on the sinus node, a drop in blood pressure fails to evoke a reflex tachycardia Heart rate hardly changes bradycardia may even develop. AV-block and myocardial insufficiency can occur. Patients frequently complain of constipation. 

Phenytoin Use with caution in hypotension and severe myocardial insufficiency. Hypersensitivity reactions Phenytoin hypersensitivity reactions are not typical they may present as one of many different syndromes (eg, lymphoma, hepatitis, Stevens-Johnson syndrome) and may include such symptoms as fever, rash, arthralgias, or lymphadenopathy. 

Salbutamol is a -receptor antagonist and a bronchodilator. Salbutamol and other -receptor antagonists should not be administered in the presence of hyperthyroidism, myocardial insufficiency, arrythmias, hypertension, and diabetes mellitus. Salbutamol is considered a drug of abuse.46 Salbutamol may cause skeletal muscle tremors, palpitation, muscle cramps, and hypersensitivity reactions. An overdose of salbutamol can cause tachycardia, CNS stimulation, tremor, hypokalemia, and hyperglycemia.47... 

A calcium-channel blocking drug, e.g. nifedipine or diltiazem, is an alternative to a p-adrenoceptor blocker use especially if coronary spasm is suspected or if the patient has myocardial insufficiency or any bronchospastic disease. It can also be used with a p-blocker, or... 

Dipyridamole. Dipyridamole. 2.2. 2".2" -l(4.8-di-l-piperidinylpyrimido 5.4-dIpyrimidine-2.6-diyl)dinitrilol-Icuakisethanol (Persantine), may be used for coronaiy and myocardial insufficiency. Its biggest use today, however. is a.s an antithrombotic in patients with prosthetic heart valves. It is a bitter, yellow, crystalline powder, soluble in dilute acids, methanol, or chloroform. A formulation containing dipyridamole and aspirin (Aggrenox) is currently being marketed as an antithromobotic. 

An open study in patients with myocardial or chronic venous insufficiency indicated that administration of 45 ml stinging nettle leaf juice daily caused an increase in the volume of urine of patients. The effect was more pronounced in patients with chronic venous insufficiency, with a 24% increase in urine volume in this group as compared to a 9% increase in the myocardial insufficiency group (Kirchhoff 1983). 

If the thyrotoxicosis remains untreated for a long time, cardiovascular complications may develop. At first there may simply be compensatory myocardial hypertrophy, but later heart failure develops with dilation of the myocardial chamber, myocardial insufficiency, and even atrjal fibrillation. No findings at autopsy are characteristic of the heart in hyperthyroidism. 

Ataxia. Drowsiness. Hepatocellular necrosis (fatal). Hypotension. Nervousness. Phenytoin is also used for treatment of chronic epilepsy. Monitor serum levels. Abrupt withdrawal may cause status epilepti-cus. Use with extreme caution in patients with hypotension or severe myocardial insufficiency. 

Fig. 4. Myocardial infarction occurs during insufficient delivery of oxygen to a portion of the heart muscle.

Nitroglycerin remains the dmg of choice for treatment of angina pectoris. It has also been found useful for the treatment of congestive heart failure, myocardial infarction, peripheral vascular disease, such as Raynaud s disease, and mitral insufficiency, although the benefits of nitroglycerin in mitral insufficiency have been questioned. 

PI (adenosine) receptors were explored as therapeutic targets before P2 receptors. Adenosine was identified early and is in current use to treat supraventricular tachycardia. A2a receptor antagonists are being investigated for the treatment of Parkinson s disease and patents have been lodged for the application of PI receptor subtype agonists and antagonists for myocardial ischaemia and reperfusion injury, cerebral ischaemia, stroke, intermittent claudication and renal insufficiency. 

Diabetes mellitus is a complicated, chronic disorder characterized by either insufficient insulin production by the beta cells of die pancreas or by cellular resistance to insulin. Insulin insufficiency results in elevated blood glucose levels, or hyperglycemia As a result of the disease, individuals with diabetes are at greater risk for a number of disorders, including myocardial infarction, cerebrovascular accident (stroke), blindness, kidney disease, and lower limb amputations. 

MI Myocardial infarction mitral insufficiency OS Left eye (oculus sinister)... 

Secondary hypotension is a sign of an underlying disease that should be treated first. If stroke volume is too low, as in heart failure, a cardiac glycoside can be given to increase myocardial contractility and stroke volume. When stroke volume is decreased due to insufficient blood volume, plasma substitutes will be helpful in treating blood loss, whereas aldosterone deficiency requires administration of a mineralocor-ticoid (e.g., fludrocortisone). The latter is the drug of choice for orthostatic hypotension due to autonomic failure. A parasympatholytic (or electrical pacemaker) can restore cardiac rate in bradycardia. 

Dopamine exhibits its primary action of the cardiovascular system, kidneys, and mesentery. It is used as a temporary agent for treating hypotension and circulatory shock caused by myocardial stroke, trauma, kidney rejection, and endogenous septicemia. The main indication for use of this drag is shock of various origins (cardiogenic, postoperational, infectious-toxic, anaphylactic), severe hypotension, and imminent renal insufficiency. Synonyms of dopamine are dopamin and inotropin. 

Strophanthin is used in severe cardiovascular insufficiency, in particular after myocardial infarction, for chronic cardiac insufficiency, cardiac decompensation, supraventricular tachycardia, and ventricular arrhythmia. Synonyms of this drug are combetin, strofopan, and others. 

Cardiovascular effects Limit use of levorphanol in acute Ml or in cardiac patients with myocardial dysfunction or coronary insufficiency because the effects of levorphanol on the heart are unknown. 

Contraindications Coronary insufficiency, pyloric stenosis, glaucoma, uremia, recent myocardial infarction, unreliable patients... 

Contraindications Uncontrolled adrenal cortical insufficiency, untreatedthyrotoxico-sis, treatment of obesity, uncontrolled angina, uncontrolled hypertension, uncontrolled myocardial infarction, and hypersensitivity to any component of the formulations... 

It is indicated in acute attacks (sublingually) and chronic prophylaxis (orally) of angina pectoris and coronary insufficiency. In acute myocardial infarction, CHF and acute LVF. 

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