PDE5 Inhibitors

If your wife is worried about your heart, she can be reassured about Viagra (sildenafil). The medication is not safe for men who use nitrates in any form, including nitroglycerin tablets and spray, long-acting nitrate tablets, nitrate patches, and amyl nitrate. But the drug is quite safe for men who do not take these medications, even if they have stable coronary artery disease or well-controlled hypertension (see Harvard Men’s Health Watch, April 2005). For example, a study from the Mayo Clinic agrees with lots of earlier research and demonstrates that Viagra is safe. More than 100 men with coronary artery disease participated in the trial. Each man underwent two detailed stress tests that used a bike for exercise and used echocardiograms as well as EKGs to monitor the result. Before one of their tests, the volunteers took Viagra (50 or 100 mg, the top dose), and before the other they took a placebo. Compared to the placebo, Viagra did produce a slight drop in systolic blood pressure (the higher number, recorded while the heart is pumping blood), but there were no changes in diastolic blood pressure (the lower number, recorded when the heart is refilling between beats), exercise capacity, symptoms, or echo-cardiograms and EKGs.

As everyone who watches TV knows, Viagra has two newer rivals. Although neither has been studied as extensively as Viagra, Levitra (vardenafil) appears to be as safe as Viagra for cardiac patients. But Cialis (tadalafil) is not a good choice. Its longer duration may be an advantage for some healthy men, but it is a disadvantage for gents with heart disease or major risk factors. Men can take nitroglycerin 24 hours after a dose of Viagra or Levitra, but they must avoid nitrates for 48 hours after taking Cialis.

Before you start Viagra, you may want to ask your doctor to check you for diabetes and other problems that can cause erectile dysfunction. And you should also think about your bicycle seat, since prolonged biking can sometimes put enough pressure on arteries and nerves to impair erections.

If Viagra is safe for your heart, how about sex itself? Disappointingly, perhaps, people seem to spend more energy thinking and talking about sex than on the act itself. During sexual intercourse, the heart rate rarely gets as high as 130 beats a minute, and the systolic blood pressure nearly always stays under 170. All in all, average sexual activity ranks as mild to moderate in exercise intensity, about the same as doing the
foxtrot or raking leaves. If you can walk up two or three flights of stairs without difficulty, you should be in good shape for sex.

Raking leaves may increase your oxygen consumption, but it probably won’t get your
motor running. Sex, of course, is different, and the excitement and stress might well pump out extra adrenaline. Both mental excitement and physical exercise increase adrenaline levels and can trigger heart attacks and arrhythmias, abnormalities of the heart’s pumping rhythm. Can sex do the same? In theory, yes. But in practice it’s really very uncommon, at least during con ventional sex with a familiar partner. Careful studies show that fewer than one of every hundred heart attacks are related to sexual activity, and for fatal arrhythmias the rate is just 1 in 200. Put another way, for a healthy 50-year-old, the
risk of having a heart attack in any given hour is about one in a million; sex doubles the risk, but it’s still just two in a million. For patients with heart disease, the risk is 10 times higher — but even for them, the chance of suffering a heart attack during sex is just 20 in a million.

It’s always good to be cautious, and it’s important to listen to your body to be sure you’re not one of the few men who develops cardiac symptoms from Viagra or from sex itself. It’s also important to listen to your wife and review the data so you agree. It may not be Zocor or aspirin, but a happy marriage is also good for your heart.

Source: Harvey B. Simon, M.D.Editor, Harvard Men’s Health Watch