Abstract | Full Text | Full Text PDF | PubMed | Scopus (95) | Google ScholarSee all References Open-label trials showed a myocardial infarction rate of only 1.0 event per 1000 person-years of treatment with sildenafil.10x10Kloner, RA and Zusman, RM. Cardiovascular effects of sildenafil citrate and recommendations for its use. Am J Cardiol. 1999; 84: 11N–17N
Erectile dysfunction (ED) is generally defined as the persistent (at least 6 months) inability to achieve and maintain penile erection sufficient to allow satisfactory sexual performance.1 It is a common condition, and recent studies predict a higher prevalence of ED in the future.2 It is estimated that ED has affected more than 150 million men worldwide and this number will reach approximately 322 million by 2025.2,3 It has affected 30 million men in the US alone.4
Towards this direction, several sufficiently powered studies have demonstrated a higher incidence of erectile dysfunction in patients with coronary artery disease, either asymptomatic or overt. At the same time, patients with erectile dysfunction are more prone to have established coronary artery stenosis of more than 50% and consequently evident CV disease[75]. This is in conformity with the “artery size hypothesis” according to which smaller arteries (e.g., penile arteries) are the first to undergo a vascular lesion prior to the larger ones (e.g., coronary arteries). Moreover, in such patients erectile dysfunction is connected to the number of occluded vessels and more interestingly occurs over three years before coronary artery disease becomes apparent[76-80].
A variety of personal habits and lifestyle choices have been linked to ED. In some ways, this is a good thing, since habits can be broken and choices reconsidered. What's more, many of the lifestyle factors that contribute to sexual problems are ones that affect overall health and well-being, both physical and mental. Addressing these factors, therefore, can have benefits beyond improving erectile dysfunction.
As a primary care doctor, my most important job is to tailor treatment for my patients while still making decisions based on the medical literature. So when patients tell me their treatment is causing undesired side effects—like ED—I work with them to create a plan to treat the condition while also finding a way to relieve those side effects. Fortunately, there are ways to deal with medically induced ED.
Contraindications for TTh include (for detailed listing, please refer to Buvat et al.45) patients with breast or prostate cancer, while patients with a palpable prostate nodule or induration, or prostate-specific antigen >4 ng/mL (or >3 ng/mL in men at high risk for prostate cancer, such as African-Americans or men with first-degree relatives with prostate cancer), should first undergo urological evaluation. Testosterone therapy is contraindicated also in patients with haematocrit >50% (TTh increases haematocrit) and uncontrolled congestive heart failure (risk of fluid retention). Risk for adverse CVD events may be increased in patients and with the mode of treatment epitomized in the study of Basaria et al.46 (see earlier).

Several drugs can produce erectile difficulties, but blood pressure drugs are near the top. ED is an occasional side effect of BP drugs like thiazide diuretics, loop diuretics, and beta-blockers, all of which can decrease blood flow to the penis and make it difficult to get an erection. However, other BP drugs, such as alpha-blockers, ACE inhibitors, and angioten-sin-receptor blockers, rarely cause ED.


Faced with concern about ED pills and the heart, the FDA has urged caution in patients who have suffered heart attacks, strokes, or serious disturbances of the heart's pumping rhythm in the previous six months, in men with a history of congestive heart failure or unstable angina, and in men with low blood pressure or uncontrolled high blood pressure (above 170/110 mm Hg). Because certain medications can boost the blood levels of these drugs, men taking erythromycin or certain antifungal or anti-HIV medications should use only low-dose PDE-5 inhibitors. Reduced dosage is also important for men with advanced age and for those with significant kidney or liver disease.
Abstract | Full Text | Full Text PDF | PubMed | Scopus (95) | Google ScholarSee all References, 56x56Wallis, RM, Corbin, JD, Francis, SH, and Ellis, P. Tissue distribution of phosphodiesterase families and the effects of sildenafil on tissue cyclic nucleotides, platelet function, and the contractile responses of trabeculae carneae and aortic rings in vitro. Am J Cardiol. 1999; 83: 3C–12C
Diabetes, high blood pressure (hypertension), elevations in blood lipids or cholesterol are considered blood vessel problems and have all been associated with Erectile Dysfunction. The blood vessel abnormalities caused by these diseases affect vessels throughout the body and often produce other symptoms of vascular diseases. Diabetics and patients with hypertension frequently have heart disease. These conditions typically interfere with the ability of the penile vessels to work properly and ultimately cause ED.
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In Eastern medicine, animal products are commonly used for their perceived health benefits. The philosophy “like nourishes like”, suggests that consuming the organ of an animal will bring benefits to the corresponding organ in one’s body is a common belief. Men seeking greater potency have turned to eating penises from goats, bull, deer, horses, seals and other mammals in the form of cooked dishes or herbal preparations. While there is no scientific evidence supporting this practice, the cultural beliefs remain strong and supplements containing extracts from animal penises are readily available in the form of capsules, often mixed with herbal compounds pitching similar erectogenic properties. A significant proportion of these potency-inducing supplements in Asia have been found to contain PDE5-inhibitors substrates such as tadalafil and sildenafil (30). However uncontrolled use of illicit PDE5-inhibitors under the guise of natural supplements remains a health threat to the general public.
Tribulus terrestris is a dicotyledonous herbal plant of the Zygophyllaceae family, used to increase serum testosterone levels, which has only been shown in animal studies (40). A prospective, randomized, double blind study of 30 men showed that Tribulus terrestris was not more effective than placebo on improving IIEF scores or serum total testosterone (41). Two accounts of hepato-nephrotoxicity have been reported in young men who ingested high doses of this herbal medication (42,43).

Having chronically high blood pressure can affect overall satisfaction with sex and affect men’s ability to achieve a firm erection. Due to constant vessel damage as a result of high blood pressure, linings of the arteries begin to harden and narrow, a process called atherosclerosis. Because blood flow is limited to the affected regions of the body, arterial blood circulation to various organs—including the heart muscles, brain, and even the groin—can be compromised, with myocardial infarctions, strokes, and erectile difficulty being common in hypertensive patients. Studies show that approximately 30 percent of hypertensive patients reported having erectile dysfunction, and approximately 49 percent of men aged 40 to 79 had both high blood pressure and ED.
• Blood Vessels: Diabetes damages blood vessels, especially the smallest blood vessels such as those in the penis. Diabetes can also cause heart disease and other circulatory problems. Proper blood flow is absolutely crucial to achieving erection. “Erection is a hydraulic phenomenon that occurs involuntarily,” says Arturo Rolla, MD, of Harvard University School of Medicine. “Nobody can will an erection!” Anything that limits or impairs blood flow can interfere with the ability to achieve an erection, no matter how strong one’s sexual desire.
Sexual dysfunction is a common, underappreciated complication of diabetes. Male sexual dysfunction among diabetic patients can include disorders of libido, ejaculatory problems, and erectile dysfunction (ED). All three forms of male dysfunction can cause significant bother for diabetic patients and can affect their quality of life. Despite this, health care providers often do not specifically ask their male diabetic patients about sexual function. This results in considerable underdiagnosis because patients are often reluctant or embarrassed to initiate discussion of these issues themselves. By not recognizing sexual dysfunction as a common organic sequel-lae of diabetes that should be addressed and treated, providers are missing an important opportunity to improve their patients' daily existence and quality of life.

The following products are considered to be alternative treatments or natural remedies for Erectile Dysfunction. Their efficacy may not have been scientifically tested to the same degree as the drugs listed in the table above. However there may be historical, cultural or anecdotal evidence linking their use to the treatment of Erectile Dysfunction.
How common is impotence? According to findings from several studies, including “The Massachusetts Male Aging Study,” overall prevalence for men between 40–70 years old is around 52 percent (or around 30 percent of all men between 18–60 years old). That’s right — nearly half of all men over 40 experience erectile dysfunction symptoms at some point. Not surprisingly, research demonstrates that impotence is increasingly prevalent with age. Around 40 percent of men in their 40s experience sexual dysfunction. Up to 70 percent of men in their 70s experience ED. (1) Every year more than 617,000 new cases of impotence occur in the United States alone.
Chlamydia and erectile dysfunction: What's the link? Some people who have chlamydia also experience erectile dysfunction (ED), which involves problems getting or maintaining an erection. Chlamydia can infect the prostate gland, leading to prostatitis, pain, and ED. In this article, learn more about the link between this common infection and ED, and treatments for both. Read now
A number of over-the-counter herbal supplements claim to treat ED. However, according to the Mayo Clinic, you should avoid products labeled as “herbal Viagra.” These supplements can increase blood flow and cause dangerous drops in blood pressure. Risk may be particularly high for men who are using nitrates. Herbal Viagra can also interact with other prescription drugs. Herbal Viagra products may contain potentially toxic compounds that aren’t listed on the label.
Abnormalities in the vascular, neural, endocrine, muscular, or psychiatric systems can result in ED.2,3 EDDM is due to multisystemic disease. Atrophy or apoptosis of cavernosal smooth muscle can occur due to loss of Bcl-2 expression in cavernosal smooth muscle and lead to ED. Abnormal amounts of advanced glycation end products is a common occurrence. These chemicals may have an effect on potassium channels that facilitate intracellular calcium release and subsequent cavernosal smooth muscle relaxation. Connective tissue synthesis is increased due to transforming growth factor-beta. The decrease in smooth muscle and the increase in collagen decreases the compliance of the erectile tissue. Neuropathic damage to both the somatic and autonomic nerves has been clearly defined in DM. Partial occlusion of the pelvic or intracavernosal arteries, hypogonadotropic hypogonadism, and depression associated with a chronic illness (DM) can all play a primary or secondary role in the development of EDDM. On a molecular level, studies have demonstrated decreased levels of endothelial and neuronal nitric acid synthase (NS) and decreased cavernosal artery and sinusoidal response to nitric oxide. Abnormalities in nitric oxide rapidly render the functional syncytium of the corpora cavernosa unable to synchronously relax. As the patient with diabetes ages, the concentration of constrictors, including endothelin, prostanoids, and possibly angiotensin, increases as the production of the relaxants, including nitric oxide, vasointestinal peptide, and prostacyclin, decreases.
The cardiovascular effects of sildenafil during exercise in patients with known or probable cardiovascular disease were studied in a randomized placebo-controlled trial of 105 men with a mean age of 66 years.63x63Arruda-Olson, AM, Mahoney, DW, Nehra, A, Leckel, M, and Pellikka, PA. Cardiovascular effects of sildenafil during exercise in men with known or probable coronary artery disease: a randomized crossover trial. JAMA. 2002; 287: 719–725
Erne P,  Schoenenberger AW,  Zuber M,  Burckhardt D,  Kiowski W,  Dubach P,  Resink T,  Pfisterer M. Effects of anti-ischaemic drug therapy in silent myocardial ischaemia type I: the Swiss Interventional Study on Silent Ischaemia type I (SWISSI I): a randomized, controlled pilot study, Eur Heart J , 2007, vol. 28 (pg. 2110-2117)https://doi.org/10.1093/eurheartj/ehm273
Penile arterial supply (top) and venous drainage (middle), longitudinal views. Bottom, Transverse and longitudinal views of venous return. From Lue TF. Physiology of penile erection and pathophysiology of erectile dysfunction and priapism. In: Walsh PC, Retik AB, Vaughan ED Jr, Wein AJ, eds. Campbell's Urology. Vol 2. 7th ed. Philadelphia, Pa: WB Saunders Co; 1998:1157-1179. With permission from Elsevier.
Getting blood glucose under control is a good anti-ED tactic. Men with diabetes and poor blood glucose control are two to five times as likely to have ED as those with good control. One study in a group of men who had had type 1 diabetes for up to 15 years with minor complications found that intensive blood glucose control lowered the risk of ED compared with conventional treatment. A study in men with type 2 diabetes found that lowering A1C (average blood glucose in the past two to three months) below 7 percent and reducing blood pressure through a combination of medication, diet, and exercise improved sexual functioning.
L-arginine, an amino acid that is naturally present in the body and helps make nitric oxide, supports a successful erection. Nitric oxide is responsible for making the blood vessels relax, which helps sustain an erection for men. A 1999 study, observed the effects of six weeks of high-dose (5 grams/day) orally administered nitric oxide (NO) donor L-arginine on men with organic ED. Thirty-one percent of those who took 5 grams/day of L-arginine experienced significant improvements in sexual function. Burns told Medical Daily, “l-arginine and deer antler velvet” have been the most popular go-to natural treatments for men.
Erectile dysfunction is common in the patient with cardiovascular disease. It is an important component of the quality of life and it also confers an independent risk for future cardiovascular events. The usual 3-year time period between the onset of erectile dysfunction symptoms and a cardiovascular event offers an opportunity for risk mitigation. Thus, sexual function should be incorporated into cardiovascular disease risk assessment for all men. A comprehensive approach to cardiovascular risk reduction (comprising of both lifestyle changes and pharmacological treatment) improves overall vascular health, including sexual function. Proper sexual counselling improves the quality of life and increases adherence to medication. This review explores the critical connection between erectile dysfunction and cardiovascular disease and evaluates how this relationship may influence clinical practice. Algorithms for the management of patient with erectile dysfunction according to the risk for sexual activity and future cardiovascular events are proposed.
PubMed | Google ScholarSee all References Interestingly, this study found no association between erectile function and the number of years or packs per day of cigarette use. In contrast, a study of 314 current smokers with ED found that the number of cigarettes smoked inversely correlated with penile rigidity as measured by nocturnal penile tumescence.27x27Hirshkowitz, M, Karacan, I, Howell, JW, Arcasoy, MO, and Williams, RL. Nocturnal penile tumescence in cigarette smokers with erectile dysfunction. Urology. 1992; 39: 101–107

Abstract | Full Text | Full Text PDF | PubMed | Scopus (58) | Google ScholarSee all References Theoretically, the risk of a cardiac event during sexual activity should be increased. Sexual activity is associated with an elevated heart rate, blood pressure level, and myocardial oxygen demand, and this increase in hemodynamic stress may result in myocardial ischemia.79x79Kimmel, SE. Sex and myocardial infarction: an epidemiologic perspective. Am J Cardiol. 2000; 86: 10F–13F
Crossref | PubMed | Scopus (539) | Google ScholarSee all References Aside from the economic costs, ED can have severe psychological effects, resulting in poor self-image, decreased self-esteem, depression, and mental stress, and negative effects on personal relationships.2x2NIH Consensus Development Panel on Impotence. NIH Consensus Conference: impotence. JAMA. 1993; 270: 83–90

Abstract | Full Text | Full Text PDF | PubMed | Scopus (95) | Google ScholarSee all References Since then, several other oral PDE-5 inhibitors have been developed, including vardenafil and tadalafil, which generated considerable interest in both the scientific and lay communities. There was also much concern about their safety, especially in men with cardiovascular disease. Compared with the 2 newer PDE-5 inhibitors vardenafil and tadalafil, sildenafil has been available for a much longer time; therefore, the vast majority of published cardiovascular safety studies have been performed on this medication. Recommended starting and maximum doses of oral PDE-5 inhibitors are shown in Table 1.
The diagnosis of ED in a patient may affect its management in two ways.30 The first relates to the fact that the ED patient, irrespective of whether he has or has not established CVD, is ‘reclassified’ into a higher risk category for future CV events. Management in this case is altered in the sense that more aggressive treatment of risk factors, as well as a close follow-up, is warranted. Implementation of biomarkers in this setting is desirable.
Talk with your doctor about your sexual health. Do not be shy or embarrassed. Your doctor has probably dealt with this issue before. If your doctor is an older man, he might even have ED. First, your doctor will figure out what is causing your ED, which can usually be done just by talking with you. Next, your doctor will look for risk factors for atherosclerosis (the Table) by asking you questions, checking your blood pressure, and performing a few blood tests. Identifying and successfully treating atherosclerotic risk factors can reduce the chance of developing major vascular events (heart attacks and strokes).
Diabetic damage doesn’t stop with these small vessels, he said. “You really have two parallel situations: You need blood flow that feeds the muscle of the penis, and you need an artery dedicated to bringing blood rapidly when a man becomes aroused and wants to be sexually active,” he said. “That artery is also affected by diabetes. They’ll say ‘I can get a partial erection, but I can’t maintain it.’ ”
Sildenafil should be taken 1–2 h before intercourse. It is important to tell patients that the drug’s effectiveness requires sexual stimulation. One patient in our clinic recently complained that he had no effect from taking sildenafil. It was later discovered that he took the pill and then sat on his couch and read a book about how to grow tomatoes!
The second way relates to the risk associated with the sexual activity in a patient with either overt or occult CVD. In this case, the diagnosis of ED should prompt an initial cardiovascular assessment based on the history and clinical examination in order to define the baseline risk according to (i) the likelihood of silent CAD18,31 (especially since ED patients have a high probability to have silent CAD) or to the stage of clinically evident CAD, (ii) other cardiovascular conditions either unrelated, or related to ED (e.g. heart failure, peripheral arterial disease).
With early detection, doctors can suggest preventive measures like statins, blood pressure meds, revamping eating habits and getting more exercise. Try these two exercises that can cut your risk of heart disease in half. The study researchers told Science Daily, “Our study supports a more aggressive CVD risk assessment and management for persons with erectile dysfunction, including young men who may otherwise be categorized as low-risk due to their young ages.” Check out the sexual health conditions affecting millennial men.
"The answer to the question, 'Can patients with heart disease safely have sex?' is almost always 'Yes,' unless they have such bad heart failure or severe artery disease that even a moderate amount of exertion will cause terrible chest pain," says Richard Stein, MD, who is director of preventive cardiology at New York City's Beth Israel Hospital. "And if that is the case, sex is probably the last thing on their minds anyway."
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The vascular endothelium has an important role in angiogenesis and vascular repair by producing regulatory substances, including NO, prostaglandin, endothelins, prostacyclin and angiotensin II. These regulatory factors regulate the blood flow to the penis by controlling smooth muscle contractility and subsequent vasoconstriction and vasodilatation. Generally, in erectile tissue, increased blood flow through the cavernosal artery increases shear stress and produces NO, which further relaxes the vascular smooth muscles and increases blood flow in the corpora cavernosa.54 These events cause penile erection. However, in ED, endothelial NO synthesis is reduced and there is increased endothelial cell death (Figure 2).55
Tribulus terrestris is a dicotyledonous herbal plant of the Zygophyllaceae family, used to increase serum testosterone levels, which has only been shown in animal studies (40). A prospective, randomized, double blind study of 30 men showed that Tribulus terrestris was not more effective than placebo on improving IIEF scores or serum total testosterone (41). Two accounts of hepato-nephrotoxicity have been reported in young men who ingested high doses of this herbal medication (42,43).
If your physician advises you that the risks of taking an erectile dysfunction medication are too high, he or she can advise you of other treatment options that can enable you to resume sexual activity without risks of complications. These might also include screening to try to determine if your erectile dysfunction has a physiological basis in need of medical intervention, can be corrected through lifestyle changes or if it may have psychological roots. After all, a heart attack or diagnosis of heart disease can lead to depression, which can also affect libido. Talk with your doctor to establish a safe, effective plan for resuming intimacy after your heart disease diagnosis.

Yohimbine is an indole alkaloid derived from the bark of the African yohimbe tree (33). Yohimbine has been noted to treat fatigue, depression, diabetes, and sexual dysfunction. A meta-analysis of seven placebo-controlled trials (34) deemed yohimbine superior to placebo for the treatment of ED with rare adverse events. The proposed mechanism of action (35) is via the inhibition of central alpha-2-adrenergic receptors, decreasing central inhibition of arousal, and increasing penile nerve stimulation resulting in increased NO. Common side effects include headache, sweating, agitation, hypertension and insomnia. Contraindications include patients on tricyclic antidepressants, anti-hypertensives and central nervous system stimulants.
Clinical practice in TCM has been an exemplary case of customized treatment with holism epitomizes the essence of TCM. TCM encompasses these aspects, taking a holistic approach to patient’s problem and these methods combine body, mind and spirit, and healings are achieved via the concept of energy rather than matter, as in modern medicine. Compared to the complexity of modern science, which is the basis of Western medicine, this concept is easily understood and comprehended, and is readily accepted because of its holistic approach.
PDE-5 inhibitors amplify the intacavernosal production of cGMP in response to nitric oxide. This is achieved through the inhibition of cGMP's breakdown by the enzyme, PDE-5. If the predominant abnormality in the individual EDDM patient is molecular, the higher tissue levels of cGMP will overcome these inhibitory factors and the patient will regain erectile function. If the physical structure (eg, the compliance) of the cavernosal tissue has been significantly compromised by apoptosis of smooth muscle or increased collagen deposits, restoration of erectile function will not be achieved. These structural changes explain the lower efficacy rates of PDE-5 inhibitors in EDDM than in the general population.
Older age. A man’s risk increases past the age of 40, as age is the variable most strongly associated with impotence. This is due to changing hormones, higher risk for heart problems and those affecting circulation, and decreased sexual desire that often occurs with increasing age. For example, based on findings from the National Health and Social Life Survey, it’s been found that “men between 50–60 years old are more than 3 times as likely to experience erection problems and to report low sexual desire compared to men aged 18 to 29 years.” (3)
Getting frequent exercise and maintaining a healthy weight are, of course, also important. Plus, avoiding or minimizing risky dietary factors such as salt, alcohol, caffeine, and too much animal products is crucial. Animal protein elevates insulin-like growth factor 1 (IGF-1) in the blood, a growth-promoting hormone that is associated with increased risk of several cancers and cardiovascular disease.19, 20
When it comes to scientific development, in Western medicine, an analytic approach is often used to identify and resolve medical challenges. A hypothesis is first derived through general observations of a phenomenon. A research plan is then carefully designed and data collected. Once sufficient data is collected, critical statistical evaluations are done and conclusions are drawn (4). Every aspects of a disease entity are studied from macroscopic to microscopic views, down to the cellular and molecular levels. The deep understanding of the role of cGMP-specific phosphodiesterase type 5 enzymes in ED and the use of phosphodiesterase-5 inhibitors in treatment of ED exemplifies the success of this approach.

According to the Cleveland Clinic, “because erectile dysfunction is caused by a complex set of psychosocial, neurologic, and vascular factors, a specific cause in a patient may remain ambiguous.” The root causes are often related to a blockage or dysfunction of blood vessels. For example, ED can be due to conditions like atherosclerosis or diabetes, hormonal imbalances or problems related to mental health. It’s been found that common causes typically include one or more of the following factors: (2)
Finally, prevalence rates will be affected by whether the study population is accrued from a single hospital/clinic setting or from a more general population of men with diabetes. For example, Siu et al.4 studied 500 Chinese diabetic men (of which 97% had type 2 disease) seen at a single medical clinic in Hong Kong during 1999 and found the overall prevalence of ED to be 63.6%. Contrast this to Fedele et al.,5 who studied 9,756 diabetic men accrued from 178 diabetes centers in Italy. Among the 8,373 men with type 2 diabetes, only 37% reported ED, considerably less than in the Chinese study.
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