Angina vasospastic

Procardia XL. Procardia XL extended-release capsules, marketed by Pfizer Labs Division of Pfizer, Inc., contain nifedipine [21829-25-4] a calcium channel blocker of mol wt 346.3. The extended release tablet is formulated as a once-a-day controlled release capsule for oral adrninistration dehvering either 30, 60, or 90 mg nifedipine. Procardia XL is indicated for use in the management of vasospastic angina, chronic stable angina, and hypertension (see Cardiovascularagents). 

We examined the effects of selective activation of histamine Hj receptors on coronary hemodynamics in two groups patients with atypical chest pain and normal coronary arteries, and patients with vasospastic angina [48]. Selective Hj receptor stimulation was achieved by infusing histamine intravenously (0.5 pg/kg/min) for 5 min after pretreatment with cimetidine to antagonize the H2 receptors. Heart rate was kept constant (100 beats/min) by coronary sinus pacing. 

Mechanism of Action An antihypertensive that inhibits calcium movement across cardiac and vascular smooth-muscle cell membranes. Potent peripheral vasodilator that does not depress SA or AV nodes. Therapeutic Effect Produces relaxation of coronary vascular smooth muscle and coronary vasodilation. Increases myocardial oxygen delivery to those with vasospastic angina. 

Unlabeled Uses Treatment of associafed neurologic deficits, Raynaud s phenomenon, subarachnoid hemorrhage, vasospastic angina... 

Vasospastic angina (Prinzmetal s variant), unstable (crescendo or preinfarction) angina, chronic stable (effort-associated) angina PO Initially, 80-120 mg 3 times a day For elderly patients and those with hepatic dysfunction, 40 mg 3 times a day. Titrate to optimal dose. Maintenance 240-480 mg/day in 3-4 divided doses. 

It is indicated in vasospastic angina, chronic stable angina, hypertension, hypertensive emergency, hypertrophic cardiomy-... 

It is indicated in treatment and prophylaxis of exertional and vasospastic angina. 

Ikeda S, Oka H, Matunaga K, Kubo S, Asai S, Miyahara Y, Osaka A, Kohno S. Astemizole-induced torsades de pointes in a patient with vasospastic angina. Jpn Circ J 1998 62(3) 225-7. 

Lette J, Gagnon RM, Lemire JG, Morissette M. Rebonnd of vasospastic angina after cessation of long-term treatment with nifedipine. Can Med Assoc J 1984 130(9) 1169-74. 

Harada T, Ohtaki E, Sumiyoshi T, Hosoda S. Paralytic ileus induced by the combined use of nifedipine and diltiazem in the treatment of vasospastic angina. Cardiology 2002 97(2) 113-14. 

Clinical use Angina (vasospastic, chronic stable and unstable), HTN, arrhythmias, migraine prophylaxis Angina (vasospastic, chronic stable and unstable), HTN, arrhythmias Vasospastic angina, HTN, nimodipine is used for subarachnoid hemorrhage Chronic stable angina... 

DRUG GROUP VARIANT (VASOSPASTIC) ANGINA CLASSIC (STABLE) ANGINA... 

Selective 5-HT subtype 3 receptor (5-HT3) antagonists may have potential in the treatment of the pain associated with MI. MCI-9042 (sarpogrelate) or other 5-HT2A antagonists may have clinical potential for the treatment of vasospastic angina, IHD, reperfusion injury, and hindlimb ischemia. Several modulators of 5-HT (5-HT transporter inhibitors and 5-HT 1 b and 5-HT2B antagonists) may have potential alone or in combination in the treatment of pulmonary hypertension. ... 

Sakata K, Miura F, Sugino H, et al. Assessment of regional sympathetic nerve activity in vasospastic angina Analysis of iodine-123-labeled metaiodobenzylguanidine scintigraphy. Am Heart J 1997 133 484 89. 

As described above, calcium channel blockers should not be administered to most patients with ACS. Their role is a second-line treatment for patients with certain contraindications to /S-blockers and those with continued ischemia despite /S-blocker and nitrate therapy. They are a first-line therapy in patients with Prinzmetal s vasospastic angina and those with cocaine-associated ACS. Administration of either am-lodipine, diltiazem, or verapamil is preferred. Agent selection based on heart rate and LV dysfunction (diltiazem and verapamil contraindicated in patients with bradycardia, heart block, or systolic heart failure) is described in more detail in the section Early Pharmacotherapy for ST-Segment-Elevation ACS above. Dosing and contraindications are described in Table 16-4. 

Prinzmetal s vasospastic angina, bronchospastic chronic obstructive pulmonary disease (COPD), asthma, occlusive peripheral vascular disease, type I diabetes mellitus that is prone to hypoglycemia, heart block, and excessive bradycardia are contraindications to /3-blockers. The main side effects of /S-blockers are... 

Drug strategies in classic and vasospastic angina involve ... 

Nifedipine is a calcium-channel-blocking agent that inhibits movement of calcium ions across cell membrane in systemic and coronary vascular smooth muscle and myocardium. It decreases peripheral vascular resistance reduces myocardial oxygen demand and relaxes and prevents coronary artery spasm. It is indicated in chronic stable angina (except Adalat CC, Afeditab CR, Nifediac CC) vasospastic angina (except Adalat CC, Afeditab CR, Nifediac CC) hypertension (except Procardia) (see also the description of Nicardipine). 

In severe exertional or vasospastic angina, the combination of a nitrate and a Ca channel blocker may provide additional relief over that obtained with either agent alone. Since nitrates primarily reduce preload, whereas Ca channel blockers reduce afterload, the net effect on reduction of oxygen demand should be additive. However, excessive vasodilation and hypotension can occur. The concurrent administration of a nitrate and nifedipine has been advocated in particular for patients with exertional angina with heart failure, the sick-sinus syndrome, orAV nodal conduction disturbances, but excessive tachycardia may be seen. 

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