PubMed | Google ScholarSee all References They evaluated 40 patients with coronary artery disease who underwent coronary artery catheterization and whose penile brachial index (PBI) was measured by Doppler ultrasonography. Although a positive correlation was noted between the PBI and the severity of coronary artery obstruction, the relationship was not strong. Also, the degree of PBI abnormality did not effectively stratify the patients according to the severity of their coronary artery blockage. This study concluded that the PBI used alone would not be an effective predictor of ischemic heart disease.
The links between hypertension and ED are increasingly recognized and the 2009 re-appraisal of European guidelines includes relevant statements.35,47 Erectile dysfunction is almost twice as frequent in hypertensive as in normotensive individuals and appears to be of higher severity. The relative risk of developing ED in hypertensive patients compared with normotensive individuals ranges from 1.3 to 6.9. Regarding pathophysiology, hypertension appears to cause ED per se, through a multitude of mechanisms that include prolonged exposure to elevated levels of systemic blood pressure, endothelial dysfunction, and circulation of vasoactive substance (with a pivotal role of angiotensin II) that lead to structural and functional alterations in the penile arteries. The largely unfounded (see earlier paragraph) notoriety of antihypertensive treatment for causing ED is one of the most predominant causes for non-adherence and discontinuation of antihypertensive therapy, and therefore, patients should be properly informed by physicians. Phosphodiesterase type 5 inhibitors are effective in hypertensive patients with ED and they can safely be co-administered with antihypertensive medication.39 Specifically for alpha-blockers, low starting doses of PDE5 inhibitors are preferred in patients already on alpha-blocker treatment, and likewise, low starting doses of alpha-blockers are encouraged in patients taking PDE5 inhibitors. Of clinical significance is that hypertensive men with ED are more likely to comply with their antihypertensive medication when under PDE5 inhibitors.
Unfortunately, government agencies often are slow to respond to new scientific information and economic and political forces make it difficult for our population to receive clear information informing them that heart disease is nutritionally induced and totally avoidable with dietary excellence. Sadly, even the American Heart Association advocates a diet that has been shown to actually increase heart disease.
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)

Crossref | PubMed | Google ScholarSee all References Risk factors for cardiovascular disease include diabetes mellitus, obesity, physical inactivity, hyperlipidemia, tobacco use, and hypertension. Often, the relative risk of each of these factors in the development of ED is difficult to assess because many patients with ED and cardiovascular disease have more than 1 risk factor. Another important consideration is the effect of cardiac disease itself on erectile function. A history of a prior myocardial infarction was not found to be a significant independent risk factor for ED in a study comparing sexual function in 50 patients who had a prior myocardial infarction with a control group of 50 patients.14x14Dhabuwala, CB, Kumar, A, and Pierce, JM. Myocardial infarction and its influence on male sexual function. Arch Sex Behav. 1986; 15: 499–504
In subsequent clinical studies, a surprisingly high percentage of EDDM patients–10% to 20%–claimed that the placebo "improved my erections," thus indicating a psychological basis for their ED. In the latter half of the 1980s, objective means were developed that could help determine if a EDDM patient had organic or psychogenic ED. The absence of rigid sleep erections confirmed by penile monitors was one criterion for organic ED. The failure of vasoactive agents (papaverine, Trimix, or prostaglandin E-1 [PGE-1]) injected into the corpora cavernosa to induce penile rigidity was another criterion for organic disease. Intracavernosal maintenance flow rates during pharmacocavernosometry and maximum cavernosal arterial flow during penile Doppler ultrasonography were additional determinants.
A considerable number of patients with ED can have psychogenic factors as the only cause, or in combination with organic causes of ED. Depression, low self-esteem and social stresses are among the psychogenic factors that can lead to ED. Depression is an independent risk factor for both ED and IHD; these three disease conditions are interlinked.51 Psychogenic ED can be managed by multiple psychological interventions such as cognitive behavioural therapy, couples counselling and guided sexual stimulation techniques.52
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.
Testosterone therapy in hypogonadism modulates metabolic components associated with CV risk. The majority of prospective clinical studies indicates that treatment achieving testosterone levels within physiological limits has beneficial or neutral effects on a lipid profile other than HDL-C, beneficial or neutral effects on inflammatory mediators, and generally beneficial effects on glycaemic state.25 The lean body mass is typically increased in hypogonadal subjects, and visceral adiposity is decreased in several studies and unchanged in the remainder. Such metabolic effects have raised interest on the potential impact on cardiovascular health. Regarding symptoms in patients with pre-existing cardiovascular conditions (angina or heart failure) TTh has been either neutral or beneficial.25 Regarding CVD risk, available clinical trial data indicate that the use of testosterone in middle-aged to elderly men does not increase cardiovascular risk25 with the exception of one study in very frail (substantial limitation of mobility and a high rate of comorbidities) elderly subjects that used an off-label high, and rapid escalation, dosing regimen.46 Prospective data from large, well-designed, long-term trials of TTh are warranted.
Apart from their beneficial effect in erectile dysfunction and their safe profile in antihypertensive medication, PDE-5 inhibitors have even more advantages to demonstrate. Several lines of evidence has proven that patients receiving PDE-5 inhibitors are more likely to initiate an antihypertensive regime and more willing to add a new agent to their existing treatment, a fact that raises significantly patient’s adherence and as a matter of fact control of high blood pressure and quality of life[63,64]. Moreover, a handful of clinical data has demonstrated the considerable vasodilating and anti-proliferative properties of PDE-5 inhibitors in the pulmonary vasculature, establishing them as a first-line treatment in patients with pulmonary arterial hypertension[65,66]. The same properties have been considered as potentially responsible for improving microcirculation in patients with secondary Raynaud phenomenon and ameliorating cardiopulmonary exercise performance in patients with heart failure[67,68]. In addition, the therapeutic implementation of PDE-5 inhibitors has expanded in the field of benign prostate hyperplasia-lower urinary tract symptoms (BPH-LUTS). The common pathophysiologic substrate between erectile dysfunction and BPH-LUTS has rendered PDE-5 inhibitors an effective treatment which significantly improves measures of both conditions while at the same time exhibits high efficacy and safety. The beneficial effect is much more pronounced when taking into consideration the fact that a-blockers, the mainstay of therapy for benign prostate hyperplasia frequently provoke sexual side effects, erectile dysfunction included[69].
The research is based on a Swedish national database of health records that includes all hospitals in Sweden. Researchers analyzed the records of men age 80 years or younger who were hospitalized for a first heart attack between 2007 and 2013. Tracking the men for an average of 3.3 years following this first heart attack, they compared outcomes among those who subsequently filled a prescription for a PDE5 inhibitor or alprostadil to those who did not. Overall just over 7 percent of men were prescribed an erectile dysfunction drug, 92 percent of whom were prescribed a PDE5 inhibitor and 8 percent of whom were prescribed alprostadil.
Patients who use this therapy should be trained under the guidance of a urologist, and sterile technique must be used. The drugs must be injected into the shaft of the penis and into one of the penile erectile bodies (corpus cavernosum) 10–15 min before intercourse. Most patients do not complain of pain upon injection. Sexual stimulation is not required, and resulting erections may last for hours. Side effects include penile pain and priapism. The cost is about $12–20 per injection.
Now that we better appreciate the complex sequence of events necessary for erections to occur, it’s no surprise that testosterone alone yields less than perfect results. Erectile dysfunction represents more than just low testosterone, which is just one facet of the spectrum of dysfunctional phenomena that cause sexual dysfunction. Nonetheless, when testosterone is combined with popular drugs like Viagra®, success is enhanced to an even greater degree—orgasmic function improves, along with erectile capacity and libido.20 Testosterone also activates penile nitric oxide; ultrasound studies have demonstrated a 27% increase in arterial blood flow into the penis with testosterone supplementation.23

The cardiovascular adverse effects of sildenafil use have been studied extensively. Phosphodiesterase type 5, although located primarily in the genitalia, also can be found throughout the systemic vasculature, although other PDEs predominate there10x10Kloner, RA and Zusman, RM. Cardiovascular effects of sildenafil citrate and recommendations for its use. Am J Cardiol. 1999; 84: 11N–17N
The bottom line is that nearly all men with diabetes who wish to have an erection adequate for sexual intercourse can do so with the therapies currently available. And with commitment and communication, the experience of erectile dysfunction can be changed from a potential personal tragedy to an opportunity for greater emotional intimacy in a couple.