BB Vs CCB
RECOMMENDED DRUG THERAPY (CALCIUM ANTAGONIST VS. BETA BLOCKER) IN PATIENTS WHO HAVE ANGINA IN CONJUNCTION WITH OTHER MEDICAL CONDITIONS
|CARDIAC ARRHYTHMIA OR CONDUCTION DISTURBANCE|
|Sinus bradycardia||Nifedipine or amlodipine|
|Sinus tachycardia (not caused by cardiac failure)||Beta blocker|
|Supraventricular tachycardia||Beta blocker (verapamil)|
|Atrioventricular block||Nifedipine or amlodipine|
|Rapid atrial fibrillation (with digitalis)||Verapamil or beta blocker|
|Ventricular arrhythmia||Beta blocker|
|LEFT VENTRICULAR DYSFUNCTION|
|Heart failure||Beta blocker|
|MISCELLANEOUS MEDICAL CONDITIONS|
|Systemic hypertension||Beta blocker (calcium antagonist)|
|Severe preexisting headaches||Beta blocker (verapamil or diltiazem)|
|COPD with bronchospasm or asthma||Nifedipine, amlodipine, verapamil, or diltiazem|
|Raynaud’s syndrome||Nifedipine or amlodipine|
|Severe depression||Calcium antagonist|
|COPD=chronic obstructive pulmonary disease. (alternatives in parentheses)|
Because long-term administration of beta blockers has been demonstrated to prolong life in patients after acute myocardial infarction and in the treatment of hypertension, it is reasonable to consider beta blockers over calcium antagonists as the agents of choice in treating patients with chronic stable angina. However, it must be recognized that beta blockers (without ISA) increase serum triglycerides and decrease HDL cholesterol with uncertain long-term consequences. In addition, these drugs may produce fatigue, depression, and sexual dysfunction. In contrast, long-term administration of calcium antagonists has not been shown to improve long-term survival after acute myocardial infarction, although diltiazem is apparently effective in preventing severe angina and early reinfarction after non-Q-wave infarctionand verapamil reduces reinfarction rates. Whereas nifedipine has been associated with the development of fewer new coronary artery lesionsin patients with established CAD.
The choice of drug with which to initiate therapy is influenced by a number of clinical factors;
- Calcium antagonists are the preferred agents in patients with a history of asthma, chronic obstructive lung disease, and/or wheezing on clinical examination, in whom beta blockers, even relatively selective agents, are contraindicated.
- Nifedipine (long acting), amlodipine, and nicardipine are the calcium antagonists of choice in patients with chronic stable angina and sick sinus syndrome, sinus bradycardia, or significant AV conduction disturbances, whereas beta blockers and verapamil should be used only with great caution in such patients. In patients with symptomatic conduction disease, neither a beta blocker nor a calcium channel blocker should be used unless a pacemaker is in place. If a beta blocker is required in patients with asymptomatic evidence of conduction disease, pindolol, which has the greatest ISA, is useful. In the case of calcium channel blockers, nifedipine or nicardipine is preferable to verapamil and diltiazem, but careful observation for deterioration of conduction is mandatory.
- Calcium antagonists are clearly preferred in patients with suspected Prinzmetal (variant) angina; beta blockers may even aggravate angina under these circumstances.
- Calcium antagonists may be preferred over beta blockers in patients with significant symptomatic peripheral arterial disease because the latter may cause peripheral vasoconstriction.
- Beta blockers should usually be avoided in patients with a history of significant depressive illness and should be prescribed cautiously for patients with sexual dysfunction, sleep disturbance, nightmares, fatigue, or lethargy.
- The beneficial effects of beta blockers on survival in patients with left ventricular dysfunction after myocardial infarction, coupled with their beneficial effects on survival and left ventricular performance in patients with heart failure, has established beta blockers as the drug class of choice for the treatment of angina in patients with left ventricular dysfunction, with or without symptoms of heart failure, together with ACE inhibitors, digitalis, and diuretics. If angina persists despite beta blockade and nitrates, amlodipine can be administered. Verapamil, nifedipine, and diltiazem should be avoided.
- Short-acting nifedipine should not be used as the initial and only agent in patients with unstable angina because the reflex-mediated tachycardia may aggravate unstable angina. However, long-acting nifedipine may be helpful if symptoms persist despite therapy with a beta blocker, aspirin, nitrates, and antithrombotic agents.
- Hypertensive patients with angina pectoris do well with either beta blockers or calcium antagonists because both agents have antihypertensive effects. However, beta blockers are the preferred initial agent for treating angina in such patients, as noted above, and an ACE inhibitor should be strongly considered for all patients with CAD who have hypertension.