Congestive heart failure phosphodiesterase inhibitors

Low risk Has asymptomatic cardiovascular disease Has well-controlled hypertension Has mild, stable angina Has mild congestive heart failure (NYHA Class 1) Palient can be started on phosphodiesterase inhibitor... 

High risk Has unstable or symptomatic angina, despite treatment Has poorly controlled hypertension Has severe congestive heart failure (NYHA Class III or IV) Had a recent myocardial infarction or stroke within the past 2 weeks Has moderate or severe valvular heart disease Phosphodiesterase inhibitor is contraindicated... 

Cilostazol is a selective cAMP phosphodiesterase inhibitor. It inhibits platelet aggregation and is a direct arterial vasodilator. It is used for the symptoms of intermittent claudication in individuals with peripheral vascular disease. Side-effects of cilostazol include headache, diarrhea, increased heart rate, and palpitations. Drugs similar to cilostazol have increased the risk of death in patients with congestive heart failure. 

Long-term treatment with inhibitors of phosphodiesterase type III is associated with increased mortality in congestive heart failure (SEDA-17, 217). 

On the premise that phosphodiesterase inhibitors also inhibit the production of cytokines, milrinone has been used in the treatment of nine patients with the systemic inflammatory response sjmdrome and compared with seven patients with congestive heart failure (4). In both groups mikinone significantly altered cardiac index, pulmonary capillary wedge pressure, and left ventricular stroke work index. In the patients with cardiac failure it also reduced systemic vascular resistance index, and the dose of adrenaline had to be increased substantially during milrinone infusion to counteract vasodilatation. 

Pimobendan is an inhibitor of phosphodiesterase type III with calcium sensitizing properties in the myocardium. It has been associated with a worrisome albeit non-significant increase in mortality in patients with chronic congestive heart failure (1). 

Some PHOSPHODIESTERASE INHIBITORS (e.g. cnoximone and milrinone) are valuable, and some exert most of their effect on the myocardium (those acting at a heart-specific subtype of this enzyme (type III phosphodiesterase) to raise the intracellular concentration of cAMP) and may be used as positive INOTROPIC AGENTS in the short-term treatment of severe congestive heart failure. 

Trade names Amcoral Cartonic Vestistol Indications Congestive heart failure Category Phosphodiesterase inhibitor Half-life 4.6 hours... 

Other useful enzyme inhibitors include acetazolamide (Diamox) (carboific anhydrase inhibitor) for the treatment of glaucoma, congestive heart failure, epilepsy and motion sickness (a very useful drug ). Sildenafil (Viagra), famous for treatment of impotence, inhibits a phosphodiesterase enzyme (PDE5) that is involved in the breakdown of ATP. 

The client in congestive heart failure is prescribed milrinone lactate (Primacor), a phosphodiesterase inhibitor. Which priority intervention should the nurse implement ... 

Inhibitors of a heart-specific subtype (type III) phosphodiesterase, which are positive inotropics, may be used in the short-term treatment of severe congestive cardiac failure, e.g. amrinone, enoximone and milrinone. However, developments of oral formulations of drugs of this type have been halted by the results of the PROMISE trial (Prospective Randomised Milrinone Survival Evaluation trial) which documented a paradoxical increase in mortality in class IV heart failure patients randomised to receive milrinone. However, some benzimidazole derivatives with class III phosphodiesterase inhibitor actions seem to be beneficial in heart failure. The agent vesnarinone is an orally active compound that may act as a class III phosphodiesterase inhibitor but appears to be a vasodilator with multiple mechanisms. See HEART FAUURE TREATMENT INOTROPIC AGENTS. 

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