Summary Statement of the American College of Cardiology and the American Heart Association on the Use of Sildenafil (ViagraT) in Patients at Clinical Risk From Cardiovascular Effects
August 10, 1998
The American College of Cardiology (ACC), in conjunction with the American Heart Association (AHA), is currently developing an expert consensus document titled "The Use of Sildenafil (ViagraT) in Patients at Clinical Risk From Cardiovascular Effects." Pending ACC Board of Trustees and AHA approval, the document is expected to be released in December 1998. Until the document is available, the ACC and the AHA are making interim recommendations to assist physicians managing cardiac patients on ViagraT. This statement reflects the current state of knowledge, realizing that modifications may be necessary in the near future as more information is evaluated.
Recommendation for Prescribing ViagraT in Patients at Clinical Risk From Cardiovascular Effects
ViagraT is absolutely contraindicated in patients who are taking any chronic nitrate drug therapy or who utilize short-acting nitrate-containing medications, due to the risk of developing potentially life-threatening hypotension. Therefore, nitrates and ViagraT should not be taken concurrently. In addition, the combination of ViagraT and inhaled nitrates, such as amyl nitrates or "poppers" (an illicit recreational drug) could prove to be fatal and should be avoided.
The cardiovascular effects of ViagraT may be potentially hazardous for patients with certain medical profiles, and clinicians need to exercise caution when advising the following patients who are considering taking ViagraT.
Patients with active coronary ischemia who are not on nitrates,
Patients with congestive heart failure and borderline low blood pressure and borderline low volume status,
Patients on a complicated multi-drug, anti-hypertensive program, and
Patients on drugs (e.g., erythromycin, cimetidine) or who have conditions (e.g., liver or renal disease) that can prolong the half-life of ViagraT.
Management of Acute Cardiac Ischemic Syndromes With Patients on ViagraT
In the event that a patient on ViagraT experiences an acute cardiac ischemic event, the physician should first try to establish the time of the last dose of ViagraT. Definitive evidence is currently lacking, but it is possible that a precipitous reduction in blood pressure may occur over the initial 24 hours following a dose of ViagraT. Administration of nitrates in this time interval should be avoided. In the event that nitrates are given following ViagraT administration, it is essential to have the capability to support the patient with fluid resuscitation and alpha-adrenergic agonists, if needed. In patients in whom the half-life of ViagraT may be prolonged, such as in renal and hepatic dysfunction, a more extended period of time between the ViagraT administration and the nitrate administration may be required. In patients with recurring mild angina after ViagraT use, other non-nitrate, anti-anginal agents, such as beta blockers, should be considered.
Patients on ViagraT with an acute myocardial infarction should be treated in the usual manner as described in the ACC/AHA clinical practice guidelines, including, where appropriate, primary angioplasty or thrombolytics. The only difference is that nitrates are contraindicated for these patients.
In patients with unstable angina, therapy should include only non-nitrate, anti-anginal medications but otherwise adhere to principles established in the clinical practice guideline available from the Agency for Health Care Policy and Research. To date, there is no evidence of significant interactions with heparin, beta-adrenergic blockers, calcium-channel blockers, narcotics, and aspirin. These agents can be used as appropriate.
Treatment of the Hypotensive Patient With Inadvertent ViagraT Nitrate Combination Effect
In patients who inadvertently received the combination of nitrates and ViagraT and who are manifesting a severe hypotensive response, nitrate and nitroprusside therapy should be immediately stopped. Depending on clinical circumstances, any of the following therapies should be considered alone or in combination:
Placing the patient in Trendelenburg position;
Aggressive fluid resuscitation;
Judicious use of an intravenous alpha-adrenergic agonist, such as phenylephrine (NeosynephrineT);
An alpha- and beta-adrenergic agonist (norepinephrine) for blood pressure support with the realization that this could exacerbate or lead to an acute ischemic syndrome;
Intraaortic balloon counterpulsation.
Copyright c 1998 American College of Cardiology
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