Cardiac abnormalities

Hyperkalemia is generally asymptomatic in patients with CKD until serum potassium levels are greater than 5.5 mEq/L (5.5 mmol/L), when cardiac abnormalities present. 

Patients with acute hyperkalemia usually require other therapies to manage hyperkalemia until dialysis can be initiated. Patients who present with cardiac abnormalities caused by hyperkalemia should receive calcium gluconate or chloride (1 g intravenously) to reverse the cardiac effects. Temporary measures can be employed to shift extracellular potassium into the intracellular compartment to stabilize cellular membrane effects of excessive serum potassium levels. Such measures include the use of regular insulin (5 to 10 units intravenously) and dextrose (5% to 50% intravenously), or nebulized albuterol (10 to 20 mg). Sodium bicarbonate should not be used to shift extracellular potassium intracellularly in patients with CKD unless severe metabolic acidosis (pH less than 7.2) is present. These measures will decrease serum potassium levels within 30 to 60 minutes after treatment, but potassium must still be removed from the body. Shifting potassium to the intracellular compartment, however, decreases potassium removal by dialysis. Often, multiple dialysis sessions are required to remove potassium that is redistributed from the intracellular space back into the serum. 

Monitor electrocardiogram continuously in patients with cardiac abnormalities until serum potassium levels drop below 5 mEq/L (5 mmol/L) or cardiac abnormalities resolve. Evaluate serum potassium and glucose levels within 1 hour in patients who receive insulin and dextrose therapy. Evaluate serum potassium levels within 2 to 4 hours after treatment with SPS or diuretics. Repeat doses of diuretics or SPS if necessary until serum potassium levels fall below 5 mEq/L (5 mmol/L). Monitor blood pressure and serum potassium levels in 1 week in patients who receive fludrocortisone. 

Cardiac conditions in which prophylaxis is recommended include presence of prosthetic valves, prior infective endocarditis, congenital cardiac abnormalities, rheumatic heart disease or any other valvular dysfunction, hypertrophic... 

A casualty with known or potential exposure to carbon monoxide blood agents but who shows no signs of neurological or cardiac abnormalities, and does not complain of discomfort (e.g., headache, difficulty breathing, etc.). If available, breath measurement indicates that the blood carbon monoxide level is less than 10%. Anyone with potential exposure to metal carbonyls should be transported to a medical facility for evaluation because of the risk of latent chemical pneumonitis from inhalation of these agents. 

Chronic exposure of volunteers to 1000 ppm 8 hours/day for 17 days caused no subjective symptoms, no cardiac abnormalities, and no pulmonary function abnormalities. ... 

Carbamazepine stimulates antidiuretic hormone activity and has been used for the treatment of neurohypophyseal diabetes insipidus. Carbamazepine induces microsomal enzymes and its metabolism is subject to auto-induction. Frequently occurring adverse effects are sedation, dry mouth, dizziness and gastrointestinal disturbances. Photosensitivity reactions, urticaria and Stevens-Johnson syndrome have been described. The elderly are more prone to mental confusion, cardiac abnormalities and problems due to inappropriate ADH secretion. 

The IV administration of propafenone is accompanied by an increase in right atrial, pulmonary arterial, and pulmonary artery wedge pressures in addition to an increase in vascular resistance and a decrease in the cardiac index. A significant decrease in ejection fraction may be observed in patients with preexisting left ventricular dysfunction. In the absence of cardiac abnormalities, propafenone has no significant effects on cardiac function. 

A score of 1 is assigned when there are combinations of chamber and outflow tract abnormalities (Fig. lOe, j). Pericardial sac swelling and/or abnormal heartbeats are frequently accompanied with other notable cardiac abnormalities, and they contribute to a score of 2 or 1 depending upon the general severity. 

Anti-yeast activity. Ethanol (100%) extract of the seed, on agar plate at a concentration of 18.7 mg/mL, was active on Candida albicans. Water extract of the seed, on agar plate was inactive on Candida albicans °b Arrhythmogenic effect. Hot water extract of the dried seed, administered orally to adults with cardiac abnormalities at a dose of 200 mg/person, produced equivocal effect . 

Sudden deaths have occurred with amphetamine use in children with cardiac abnormalities, and clinicians are cautioned against administering amphetamine stimulants to patients with structural cardiac abnormalities. 

Sinus bradycardia (less than 50/minute) is reported in up to 25% of acromegalic patients taking octreotide, and conduction abnormalities are also commonly reported in these patients. This adverse effect is reported only rarely in other recipients of somatostatin or octreotide, probably reflecting the high rate of cardiac abnormalities due to acromegaly (9). 

Daunorubicin (Daunomycin and Cerubidine) and doxorubicin (Adriamycin) bind to and cause the intercalation of the DNA molecule, thereby inhibiting DNA template function. They also provoke DNA chain scission and chromosomal damage. Daunorubicin is useful in treating patients with acute lymphocytic or acute granulocytic leukemia. Adriamycin is useful in cases of solid tumors such as sarcoma, metastatic breast cancer, and thyroid cancer. These agents cause stomatitis, alopecia, myelosuppression, and cardiac abnormalities ranging from arrhythmias to cardiomyopathy. 

Instances of distress in the newborn have been reported after treatment of their mothers with tricyclic antidepressants in the period before delivery (134). In one case, a neonate had signs of congestive heart failure without cardiac abnormality another had tachycardia and myoclonus a third had respiratory distress and neuromuscular spasms. These effects were thought to have resulted from both the adrenergic and anticholinergic effects of the tricyclic antidepressants, which readily pass the placenta and should be avoided during the perinatal period. 

There has been some concern about the cardiovascular safety of citalopram, mainly because of animal studies showing effects on cardiac conduction. These most commonly occur in large overdoses, in which a variety of cardiac abnormalities, including QTC prolongation, have been noted. However, this can occur with therapeutic doses too. 

Many patients will require cardiac investigation beyond ECG (Table 13.3) although the likelihood of finding a cardiac abnormality on routine transthoracic echocardiography in patients without prior known cardiac abnormality is low (Table 13.4) (Beattie et al. 1998). Patients with a suspected cardiac source of embolism should certainly have transthoracic... 

Table 13.4. Pooled prevalence of various cardiac abnormalities on transthoracic echocardiography in patients with ischemic stroke without prior known cardiac disease...

Copper Anaemia Menkes (kinky hair) syndrome Cardiac abnormalities/heart disease Wilson s disease Hepatic injury and jaundice Headache, vomiting Haemolytic shock... 

Robineau, P. (1987). Cardiac abnormalities in rats treated with methylphosphonothiolate. Toxicol. Appl. Pharmacol. 87 206-11. 

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