P1246341512jPZdQ

1
CVD and Sexual Dysfunction
Melvin Cheitlin MD Jonathan Abrams MD Nancy
Houston-Miller RN
2
Nitric oxide release in sexual stimulation
CNS erotic stimulation
Neural transmission
Penile endothelial cells
NITRIC OXIDE
3
Role of cyclic-GMP in penile erection
smooth muscle relaxation
vessel dilatation
nitric oxide
Blood filling lacunae in corpus cavernosum
pushing against tunica albuginea
cyclic-GMP
obstruction of venous outflow
4
Sildenafil inhibits the enzyme PDE-5
Sildenafil citrate
Nitric oxide
X
phosphodiesterase-5
Cyclic GMP
X
5
Sildenafil side effects
Sildenafil citrate
specific for phosphodiesterase-5 (PDE-5) in
penis selectivity for PDE-6 in retina
(responsible for visual side effects) drop in
systolic pressure 8-10 mm Hg drop in diastolic
pressure 5-6 mm Hg erection tenable only when
accompanied by stimulation of nitric oxide
(ie, erotic stimulation)
6
Sildenafil and vasodilatation
Sildenafil citrate
normally SLOW vasodilation no increase in HR no
sympathetic response no increase in cardiac
output no increase in contractility BUT interacts
with organic nitrates to produce significant
hypotension
7
Sildenafil, original studies

• No differences in MI or death were seen between
  those on placebo versus sildenafil in studies of
  3700 people.
• The following subjects were excluded
• - patients with stroke or MI within 6 months
• - patients with unstable angina, CHF
• - patients with uncontrolled diabetes or
  BP 150/110 or
• patients with severe renal or hepatic disease

8
Sildenafil, original studies

• Less than 25 of patients in these studies were
  over 65 years.
• Patients with hypertension in the original safety
  trials were typically on simple regimens to
  control their blood pressure.
• The effect of sildenafil on patients with
  hypertension and who are on multiple medications
  is not known.

9
Physical burden of sexual activity

• General energy expenditure in sexual activity is
  3-7 metabolic equivalents (METS), comparable to
  mild to moderate physical activity.
• This expenditure depends on baseline status and
  differences in fitness levels.
• Use stress testing to risk stratify certain
  patient populations (eg, recent MI,
  hospitalization for unstable angina, CHF,
  multiple drugs for HTN).

10
Risk for acute MI during sexual activity

• There exists a 2-fold increase in risk for MI
  within 2-3 hours following sexual activity.
• The baseline risk of having an MI during sex is
  very low, less than 1 in terms of all
  infarctions.
• The risk factors for coronary artery disease and
  erectile dysfunction are comparable.
• When in doubt, stress test prior to resumption of
  sex or de novo sex in sedentary men at risk.

11
The use of both nitrates and sildenafil results
in hypotension
Sildenafil citrate
Nitrates

-
Nitric oxide
phosphodiesterase-5
Cyclic GMP
-
HYPOTENSION
12
The concomitant use of sildenafil and nitrates is
contraindicated.
All men presenting with acute coronary syndromes
must be asked if theyve used Viagra within the
preceding 24 hours.
All patients given Viagra must be repeatedly told
not to take nitrates.
13
Discussing sexual history with patients

• As late as 1996, less than 1/3 of patients
  received sexual counseling at the time of MI,
  while up to 85 of patients appear willing to
  talk to their physician about sex.
• When health-care professionals neglect to discuss
  their patients sexual history, patients
  experience
• - conflicts in relationships
• - diminished quality of life
• - decreased frequency of sexual activity

14
Key points in counseling a patient on sexual
activity
Provide information on the risks of sexual
activity.

• In clinically low-risk individuals, risk of AMI
  is 1 per year.
• By including sex at a frequency of once per week,
  then the risk of AMI is 1.01 per year.
• In high risk patients having sex once per week,
  the risk of AMI is 1.2 per year.

15
Key points in counseling a patient on sexual
activity
Provide information on when to resume sexual
activity.

• Generally, in first 2-6 weeks after AMI it is
  safe to resume sexual activity.
• Up to 80 of patients NOT provided this
  information are fearful in the first 6 months
  while resuming activity.

16
Key points in counseling a patient on sexual
activity
Transition to full sexual participation may
involve masturbation so that patients feel more
comfortable resuming sexual intercourse.
Patients should be aware of their environment,
avoiding sexual activity in association with
heavy meals, alcohol, temperature changes and
fatigue.
17
Key points in counseling a patient on sexual
activity
Physicians and patients should be aware of energy
costs ( 2.5-3 METS).

• This workload is not significantly different with
  regard to position during sex.
• The sex act is not a steady-state workload,
  unlike treadmill testing.
• Patients should be cautioned about warning
  signals such as chest discomfort and shortness of
  breath.

18
Key points in counseling a patient on sexual
activity
Physicians should be aware of medications that
may be of use in treating sexual dysfunction.

• Sildenafil is contraindicated in patients taking
  long acting nitrates.
• Other side effects include impaired color
  discrimination, headache, flushing and rhinitis.
• Concomitant use of certain medications is
  associated with increased plasma levels of
  sildenafil.

19
Sexual counseling in women with cardiovascular
disease

• Women have greater difficulty with psychosocial
  adjustment, higher levels of anxiety, depression
  and sleep disturbances after MI and the
  development of coronary artery disease. Up to 1/3
  of women may not resume sexual function at all.
• A need for counseling exists irrespective of
  marital status.
• Many more studies are needed.

20
CVD and sexual dysfunction

• One of the biggest issues with physicians is the
  long list of things they have to discuss with
  patients. Unless we begin to cue them in some
  way, to bring this subject up, its another one
  that gets lost along the way. The issue of
  erectile dysfunction has to be brought to the
  forefront.
• Nancy Houston-Miller
• Associate Director
• Stanford Cardiac Rehabilitation Program
• Stanford University School of Medicine
• Stanford, CA