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These result from the transection of small blood vessels and may continue to ooze into the surgical feld generic 40 mg cialis extra dosage with mastercard erectile dysfunction treatment psychological causes, signifcantly adding to the volume of blood which may obscure the surgical feld buy cialis extra dosage no prescription discussing erectile dysfunction doctor. In addition buy genuine cialis extra dosage line erectile dysfunction diabetes uk, such an ooze may4 obscure the end of the endoscope requiring either the endo- scope scrubber to be used or the endoscope to be removed from the nose to be cleaned. If the axillary fap approach to the frontal recess is used (see Chapter 7), the cut mucosal edge may bleed and this can be controlled by the use of the suction bipolar cautery. Other common areas where bleed- ing is seen are the posterior region of the maxillary sinus, the sphenopalatine region of the lateral nasal wall, and from the anterior wall of the sphenoid below its ostium. The suction bipolar allows the bleeding vessels to be accurately identi- fed and cauterized. The needle is in the region of the axillary fap and the white arrow indicates the injection site on the anterior end tifcation of the bleeding point, which is a signifcant advan- of the middle turbinate. When the manipulating lever (black arrow in A) is relaxed the suction retracts behind the bipolar paddles (C). The Anatomy of the Greater Palatine Canal and Local opening of the foramen into the canal is funnel­shaped and Anesthetic Infltration of the Pterygopalatine Fossa the canal is angled at 45 degrees to the hard palate. In a cadaver study performed in our department to evalu- Injection of local anesthetic into the pterygopalatine fossa ate the anatomy of the greater palatine canal, 20 cadaver does improve the surgical feld. There are two approaches and the less reliable were performed in the plane of the greater palatine canal. This should cause vasospasm of the vessels exiting the fo- This was done to ascertain the likelihood of damage to the ramen. However, because the foramen is not easily located, contents of the fossa (branches of the maxillary nerve, maxil- the resulting vasoconstriction achieved may not be as great lary artery, and pterygopalatine ganglion) and the orbit. Note as injecting the pterygopalatine fossa through the greater that the bend in the needle stops at the soft tissue overlying palatine canal. A surgeon not involved in the surgery randomly infl- trated one fossa transorally so that the operating surgeon would not be aware of which side had been infltrated. The surgeon then alternated the surgery on the patient and assessed the surgical feld on each side. Statistical analysis showed that the side that had received the pterygopalatine fossa injection had signifcantly better surgical feld (mean surgical grade of 2. The funnel-shaped opening of the greater palatine canal Inhalational agents used during general anesthesia cause into the pterygopalatine fossa is indicated with a white arrow. This funnel­shaped attempt to compensate for this reduced venous return and entrance into the greater palatine canal means that it can low cardiac output, refexes increase the heart rate in an be difcult to determine exactly where the pterygopala- attempt to improve the cardiac output. This is performed What they also showed was that esmolol, a highly selec- by placing a tongue depressor in the mouth and holding tive b1 b­blocker, improved the surgical feld with a much down the tongue, then passing a fnger and the endoscope smaller drop in blood pressure. The fnger frst locates the poste- cardioselective b adrenergic receptor­blocking drug that has rior free edge of the hard palate and then slides anteriorly a fast onset and short half­life. The foramen should be sodium nitroprusside, which while efectively lowering the felt as a depression directly anterior to the free edge about blood pressure results in a compensatory increase in heart midway between the second molar tooth and the midline rate, esmolol is highly efective at depressing cardiac out- of the palate. Visualize the fnger palpating the foramen put and results in a slowing of the pulse rate despite a fall on the monitor and identify the spot on the palate as the in blood pressure. With the needle bent sion and has a very short half­life (around 3 minutes) so its at 25 mm and at a 45­degree angle, insert the needle into efect can be closely controlled. The assumption is that the needle had just missed The expense of this drug stimulated our department to the foramen and that a slight adjustment needs to be made conduct a double blind placebo controlled prospective study before the foramen is located. If repeated attempts to in- in the efects of metoprolol taken orally 20 minutes before troduce the needle fail, then the landmarks for the foramen general anesthetic, as compared with a vitamin B placebo. There was no needle is reintroduced until the foramen is located by the signifcant diference in blood pressure or surgical felds in needle advancing into the greater palatine canal without the two groups. However, what was interesting was the sig- any resistance up to the bend in the needle. After aspirating nifcant correlation between heart rate in the overall patient (to ensure that the needle is not in a blood vessel), the pter- group with surgical grade. Thus, irrespective of whether2 ygopalatine fossa is infltrated with 2 mL of 2% lidocaine a b­blocker is given to the patient or not, if the heart rate and 1:80 000 adrenaline. However, the major- an elevation of blood pressure before depressing the cardiac ity of our patients fuctuate between grade 2 and 3 on the output by inhibiting the central cardiac regulatory mecha- Boezaart scale. It should be used with caution and should be given be aided by the use of suction dissection instruments* (see in small increments, as the efect is not easily reversible. This is benefcial for the majority of patients change from a dissecting instrument to a suction to clear the as this mild hypotension allows the small blood vessels in surgical feld. Grade 4 or 5 Please note that surgery should not be performed if the sur- Total Intravenous Anesthesia and Inhalational Agents gical feld is grade 5. As can be seen from the previous discussion, vasodilation Check positioning of the patient is detrimental to the surgical feld. General anesthesia Check that you have properly infltrated the lateral wall of results in vasodilation and the extent of the vasodilation the nose with lidocaine and adrenaline is to a certain extent dependent on the type and quan- Place neuropatties soaked with cocaine and adrenaline in tity of inhalational agent used. Halothane gives signif6 - the surgical feld cant vasodilation and should not be used. Isofurane and6 Check the patient’s pulse rate and, if greater than 60, ask sevofurane produce less vasodilation but if they are used the anesthetist to adjust this to below 60 (using b­blockers to deepen the level of anesthesia with the intention of if not contraindicated) lowering the blood pressure, signifcant vasodilation can If the patient is hypertensive ask the anesthetist to bring occur. Although it does depress the heart, this response is not dose­dependent and increasing the infusion If there is a specifc bleeder, cauterize it with the suction rate of propofol will not result in an increasing suppression bipolar. It, however, does not af- If the bleeding is emanating from the posterior region of fect the muscle tone of the prearteriolar and precapillary the nasal cavity, consider replacing the neuropatties and sphincters and does not cause vasodilation and increased performing a pterygopalatine fossa block. Remember to stay within ment we performed a randomized controlled single blinded the safe range of mean blood pressure (. Laryngoscope 1987;97(11):1270–1273 sphenopalatine artery for refractory posterior epistaxis. The efect of 2000;14(4):261–264 beta­blocker premedication on the surgical feld during endoscopic 10. Laryngoscope 2004;114(6):1042–1046 of pterygopalatine fossa injection with local anesthetic and adrenalin 3. Comparison of sodium nitro- in the control of nasal bleeding during endoscopic sinus surgery. Am J prusside­ and esmolol­induced controlled hypotension for functional Rhinol 2005;19(3):288–292 endoscopic sinus surgery. Re: Moderate controlled hy- Oral Pathol 1979;47(2):109–113 potension with sodium nitroprusside does not improve surgical condi- 12. Pterygopalatine fossa infltration through the tions or decrease blood loss in endoscopic sinus surgery. Otolaryngol Head Neck Surg 1999;121(5):639–642 A receptor blockade antagonizes the immobilizing action of propofol 6.

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Most of the hair in women are androgen dependent cheap cialis extra dosage online erectile dysfunction treatment for heart patients, but some hair are estrogen dependent buy generic cialis extra dosage 40 mg what food causes erectile dysfunction, e buy cialis extra dosage 200mg fast delivery erectile dysfunction 33 years old. This is evident by maximal scalp hair growth seen during pregnancy, and it occurs due to prolongation of the anagen phase because of estrogen. Further, despite normal adrenarche, pubarche is absent in patients with hypogonadotropic hypogonadism and Turner’s syndrome as adrenal andro- gens act in concert with estrogen for the appearance of pubic and axillary hair. This is evidenced by the absence of hair in these areas in patients with 5α-reductase deficiency. However, there is a poor correlation between hair growth and serum androgen 130 6 Disorders of Androgen Excess levels as hair growth also depends on local growth factors and end-organ sensi- tivity. Hair follicular growth is a continuous process characterized by a period of growth (anagen), transition (catagen), and rest (telogen). The anagen phase for scalp hair usually lasts for 2–6 years followed by the catagen phase lasting for 1–2 weeks and finally ends into the telogen phase for 4–6 weeks. Estrogen regulates the anagen phase of the scalp hair and is responsible for longer hair in women. Ovary and adrenal are the primary source of androgens, and adipose tissue is involved in the peripheral conversion of weaker androgens (e. Therefore, pathogenic abnormalities causing hirsutism involve ovary, adrenal gland or adipose tissue. Other endocrine disorders associated with hirsutism include Cushing’s syndrome, acromegaly, and hyper- prolactinemia. Drugs causing hirsutism are phenytoin, minoxidil, cyclosporine, diazoxide, and androgens or androgenic progestins. Idiopathic hirsutism is the diagnosis of exclusion and is characterized by regular menstruation, normal androgen profile, and no ovarian or adrenal abnormalities. Modified Ferriman–Gallaway score is an objective score to define hirsutism, and a score >8 is considered as significant. A score of 8–15 is classified as mild hirsutism and >15–36 as moderate to severe hirsutism. However, this data is derived from Caucasian women and has not been validated in other racial/ ethnic groups. It is observer dependent as the grading from 0 to 4 is subjective and does not include hair growth on side burn, nape of the neck, and phalangeal and perianal region. In addition, a woman having significant hair growth over upper lip/chin but may still have a total score of <8; thus, this score does not reflect the cosmetic concern of the patient. The classic syndrome originally described by Stein–Leventhal was based on the histomorpho- logical description of the ovary. The usual menstrual irregularities are oligomenorrhea or secondary amenorrhea and sometimes primary amenorrhea or menorrhagia. Anovulation and poorly estrogenized endometrium are the causes for primary amenorrhea. Menorrhagia is a rare pre- sentation which occurs due to endometrial hyperplasia and manifests as irreg- ular breakthrough bleeding. It is a consequence of unopposed estrogen action and deficient progesterone production due to chronic anovulation/luteal phase defects. Folliculogenesis is a sequential, regulated, complex process and includes fol- licular recruitment, growth, and maturation that eventually result in ovulation. All these events result in impaired folliculogenesis and chronic anovulation which clinically manifests as oligomenorrhea or amenorrhea. Why is obesity associated with hypogonadism in males and hyperan- drogenism in females? A unique gender paradox of obesity is that it causes hyperandrogenism in females and hypogonadism in males. Obesity in women is associated with “differential insulin resistance” characterized by resistance to the metabolic actions of insulin but preserved sensitivity to proliferative actions in ovary. This results in thecal cell hyperplasia and overproduction of ovarian andro- gens. Hence in obese women, structurally the gonad is ovary, but functionally it behaves like a testis. In addition, obesity is associated with increased 17β-hydroxysteroid dehydrogenase activity in adipose tissue, thereby promoting peripheral conversion of androstenedione to testosterone. On the contrary, obesity in men is associated with functional hypogonadism as insulin resistance has inhibitory effect on hypothalamo–pituitary–testicular axis. But in morbidly obese men, due to markedly enhanced aromatase activity, free tes- tosterone is also reduced, because of the inhibitory effect of estradiol on the hypothalamo–pituitary–testicular axis. This is attributed to luteal phase defect, senescent ova fertilization, and dysglycemia. Luteal phase defect is due to impaired follicular growth and development resulting in defec- tive corpus luteum and inadequate progesterone production, thereby leading to miscarriage. All guidelines essentially include clinical and/or biochemical hyperandrogen- ism and menstrual irregularities with or without polycystic ovaries on imag- ing. Ethnic variability in quantification of hirsute score, lack of assessment of tissue sensitivity to androgens, alterations in androgen levels with age, and non-standardization of androgen assays across the laboratories are the deficits associated with criteria based on clinical and/or biochemical hyperandrogen- ism. Ovulatory dysfunction is difficult to quantify, and 20% of women despite anovulation may have regular menses, thereby making it difficult to diagnose ovulatory dysfunction. These patients are usually lean with normal stature, and family history of hirsutism may be present. Treatment with glucocorticoids is less effective; therefore, antiandrogens and oral contra- ceptives are preferred for treatment of hirsutism and menstrual irregularities. However, glucocorticoids are in those with premature adrenarche and acceler- ated bone maturation. Prominent thecal hyperplasia and predominantly solid appearance of ova- ries with few or no cysts are characteristic of ovarian hyperthecosis on imaging. The case illustrated below shows severe virilization in a young girl with ovarian hyperthecosis. A detailed history and physical examination usually points to the diag- nosis of hyperandrogenic disorders. Patients who require workup include those with hirsutism (score >8-15 with menstrual irregularities or isolated hirsutism with score >15), menstrual irregularities, virilization, rapidly progressive hirsutism, infertility, galactorrhea, and stigma of Cushing’s syndrome. What are the minimum investigations required in a woman with disorder of androgen excess? Theca cells produce a regulated quantum of androgens which are available as a precursor for estradiol biosynthesis in granulosa cells. Therefore, the ovary becomes a major source of androgens and adipose tissue for estrogen. Endometrial estrogenization, timely ovulation, and progesterone withdrawal are the prerequisites for normal menstruation. Patients with oligomenorrhea with clinical estrogen sufficiency (Tanner breast stages 4–5) should be subjected to progesterone challenge (medroxyprogesterone acetate 10 mg/day for 5–7 days) after ruling out pregnancy. If progesterone withdrawal results in bleed- ing, it suggests that the endometrium is adequately primed with estrogen, and the cause of oligomenorrhea is anovulation.

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Data evaluating the outcomes of psychological interventions in pediatric patients with heart disease are limited and more so in pediatric device patients buy cialis extra dosage 100mg free shipping erectile dysfunction can cause pregnancy. However discount cialis extra dosage 40mg overnight delivery impotence new relationship, exercise training did not improve anxiety buy cheap cialis extra dosage 50mg erectile dysfunction medication class, depression, or externalizing behaviors. Disease self-management groups are common in other areas of pediatric medicine and have generally been shown as helpful in reducing disease burdens in areas such as epilepsy, diabetes, and asthma (46,47,48,49,50). Mean tailored cardiac rehabilitation significantly longer in cardiac rehab (2003) age = therapy group (p = 0. However, the goal of fully addressing the patient and family adjustment to the disease and device is worth pursuing. To address this, we suggest a working framework in which the majority of the psychosocial issues associated with cardiac devices could be conceptualized as an interconnected triad of fears in the categories of “Self,” “Device/Disease,” and “Relationship to Society/Peers” (Fig. Fears relating to “Self” can include issues with self-image (perceiving oneself as “different”), body image, self-esteem, and coping with personal limitations, whether self-imposed or medically mandated. For a young person, and particularly for adolescents, whose emerging identity is strongly influenced by peers and their surroundings, the concerns about “Relationships to Society/Peers” are particularly important. These may include fear of not belonging to their peer group, fear of being perceived as different, frustrations with parental overprotection, and the challenges of dealing with isolation, rejection, and discrimination. Creating a clinical safety net for our pediatric device patients can be initiated with attention to this triad of fears. We suggest that the conceptualization of fears leads to specific clinical actions that P. For clinicians, the first step is to acknowledge that most pediatric patients with an implantable cardiac device are at risk of psychosocial sequelae. Discussions of stress, anxiety, and activity should be integrated into the visit with a goal of recognizing patient and family distress. Demonstrating openness and confidence in referring for psychological assessment and treatment is key. Finally, we suggest that a set of clinical strategies for routine maintenance of care “beyond the device” can be instituted. Educating the patient and family about the disease and device, including the development of a “shock plan,” can empower families by eliminating some elements of the unknown. Ensuring age-appropriate device programming and reassessing activity restrictions on an individual basis allow the clinician to advocate more confidently for increased physical activity in those patients who have limited themselves due to avoidance. In those whose condition mandates limitations, focus on improving quality of life by exploring skills and identifying interests within the constraints of their device and disease. Consider recommending participation in cardiac disease–specific camps, which may restore some sense of “belonging” to patients who feel isolated by their disease (54,55). Finally, refer for psychological evaluation and therapy with an emphasis on normalizing patient and family stress. Recognize and normalize pediatric patient and family distress Consider risk and resilience factors to promote adjustment Provide supportive care as a healthcare team by reinforcing/praising personal coping efforts of patients and families Demonstrate openness and familiarity with referring for psychosocial care Encourage behavioral activation in patients and families Concentrate on and develop conversation on quality-of-life activities vs. The current chapter identified common challenges for pediatric patients with devices including differences in quality of life, psychological distress, and social functioning that warrant additional clinical consideration and research. Many of the fears of pediatric device patients can be conceptualized as an interconnected triad of fears in the categories of “Self,” “Device/Disease,” and “Relationship to Society/Peers. Machines in Our Hearts: The Cardiac Pacemaker, the Implantable Defibrillator and American Health Care. Implantation trends and patient profiles for pacemakers and implantable cardioverter defibrillators in the United States: 1993–2006. Cardiac rhythm devices in the pediatric population: utilization and complications. Implantable cardioverter defibrillator criteria for primary and secondary prevention of pediatric sudden cardiac death. Sudden cardiac death and the use of implantable cardioverter- defibrillators in pediatric patients: The pediatric electrophysiology society. Pediatric bridge to heart transplantation: Application of the Berlin Heart, Medos and Thoratec ventricular assist devices. Mechanical left ventricular support as a bridge to cardiac transplantation in childhood. Impact of psychological factors on the pathogenesis of cardiovascular disease and implications for therapy. Patient acceptance of the implantable cardioverter defibrillator in ventricular tachyarrhythmias. Securing life through technology acceptance: The first six months after transvenous internal cardioverter implantation. Health related quality of life and social support in pediatric patients with pacemakers. Psychosocial aspects of caring for pediatric pacemaker recipients and their families. Quality of life in pediatric patients with implantable cardioverter defibrillators. Perceived self-competence, psychosocial adjustment, and quality of life in pediatric patients with pacemakers. Quality of life and functional capacity after long-term right ventricular pacing in pediatrics and young adults with congenital atrioventricular block. Psychiatric functioning and quality of life in young patients with cardiac rhythm devices. Implantable cardioverter defibrillator therapy for life-threatening arrhythmias in young patients. Psychosocial factors and quality of life in children and adolescents with implantable cardioverter-defibrillators. Psychological functioning and disease-related quality of life in pediatric patients with an implantable cardioverter defibrillator. Acceptance and psychological impact of implantable defibrillators amongst adults with congenital heart disease. Outpatient left ventricular assist device support: A destination rather than a bridge. Recovery of major organ function in patients awaiting heart transplantation with Thoratec ventricular assist devices. Assessment of submaximal exercise capacity in patients with left ventricular assist devices. Exercise performance in patients with end-stage heart failure after implantation of a left ventricular assist device and after heart transplantation: an outlook for permanent assisting? Change in quality of life from before to after discharge following left ventricular assist device implantation. Quality of life and psychological well-being during and after left ventricular assist device support.

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Other emerging quantitative modalities in 3-D echocardiography include the ability to guide cardiac resynchronization therapy (63 order cialis extra dosage 200mg on-line erectile dysfunction caused by hernia,64 buy cheap cialis extra dosage on line injections for erectile dysfunction cost,65) buy cialis extra dosage 50 mg visa effexor xr impotence, although these techniques are not yet widely used in the pediatric population. The anterior (white arrow) and posterior (asterisk) tricuspid valve leaflets can be identified; the septal leaflet is open but oriented into the plane of the image. The floor of the right atrium and coronary sinus ostium (grey arrow) is also demonstrated. Three-Dimensional Guidance of Percutaneous Cardiac Interventional Procedures The utilization of 3-D echocardiography is expanding to the interventional world with increasing use during catheter-based procedures (Fig. Three-dimensional echocardiographic guidance impacts treatment of structural heart disease in the cardiac catheterization laboratory during transseptal puncture, septal defect closure, left atrial appendage occlusion, and mitral valve repair. The left atrial disc of the device can be seen centrally along the left atrial aspect of the septum (arrow). Echocardiographic Evaluation of Interventional Procedures As the field of interventional catheterization has evolved, echocardiographic techniques to evaluate and monitor these procedures have also expanded. In this section, we will review common techniques in echocardiographic evaluation of device placement in the catheterization laboratory. These transducers can image in a longitudinal plane with a sector angle of 90 degrees, and a depth of penetration to 12 cm. Regardless of the echocardiographic modality being employed, the goals of echocardiographic evaluation before, during, and after device deployment include: (a) Preprocedure assessment of pertinent anatomy; (b) monitoring during intervention and device deployment; and (c) anatomic and functional assessment after device deployment. Assessment of tissue rims around the defect is important in determining the ability of the device to anchor around the defect margins (Fig. During the procedure, the position of sheaths and guide wires should be documented and communicated to the interventionalist. Full deployment of the following (right atrial) disc and assessment of the entire device relative to its position on the atrial septum, presence/absence of residual shunting, and potential impingement on adjacent structures should be evaluated prior to release P. It is important to know the unique characteristics of each device during the imaging evaluation (74,75,76,77,78). In panel B, the device has been fully deployed, and now sits flush against the atrial septum. Assessment of tissue rims around the defect is important in determining the ability of the device to anchor around the defect margins, and to assess the potential of the device to impinge on other important cardiac structures, for example, aortic valve, atrioventricular valves, and chordal apparatus. During the procedure, the position of sheaths and guide wires should be documented and communicated to the interventionalist. Full deployment of the device and assessment of the entire device relative to presence/absence of residual shunting, and potential impingement on adjacent structures should be evaluated prior to release of the device. Findings should be reevaluated following release of the device to exclude embolization (Fig. Most frequently, transthoracic echocardiography is utilized to assess preprocedure ductal size and morphology, and to evaluate residual shunting after device placement. Contrast Echocardiography Contrast echocardiography involves administration of one of two distinct contrast agents—agitated saline or commercially available transpulmonary contrast—each with a distinct purpose and use. Agitated Saline Contrast Echocardiography Principle Agitation of saline produces microbubbles of gas (10 to 100 μ in diameter) that pass through the circulation until they are filtered and absorbed by transit into a capillary bed. With a systemic intravenous injection, therefore, the microbubble “cloud” will follow the downstream flow of blood, pass into the large systemic veins and P. In the absence of right-to-left shunts, the microbubbles should not be present in the left side of the heart because of filtering and absorption in the pulmonary capillary bed. The presence of contrast in the left side of the heart after an intravenous injection of agitated saline, therefore, is a very sensitive marker for the existence of a right-to-left intrapulmonary or intracardiac shunting (86). Likewise, the presence of contrast in the right side of the heart after a left heart injection (e. Indications Agitated saline contrast is helpful whenever a right-to-left intrapulmonary or intracardiac shunt is suspected but cannot be definitively detected by standard echocardiographic modalities. These scenarios include the patient with a suspected thromboembolic stroke, unexplained cyanosis, suggestion of an intracardiac shunt on an echocardiogram with suboptimal windows, low oxygen saturations following Glenn or Fontan operation (87), suspected baffle leak following atrial switch procedure for transposition, suspected unroofed coronary sinus, and with suspected hepatopulmonary syndrome (Fig. With intrapulmonary shunts, as seen in pulmonary arteriovenous malformations occurring in cavopulmonary connections and in the hepatopulmonary syndrome, microbubbles in the left heart usually appear three to four cardiac cycles after the contrast cloud appears in the right heart. The exact site of initial left heart microbubble appearance should also be carefully noted since the location of the right-to-left shunt can be pinpointed to either that level or upstream to it. Likewise, an injection in a lower-extremity vein may be more appropriate when a leak or persistent fenestration is suspected in a Fontan conduit. Sometimes agitated saline contrast should be administered through central catheters during cardiac catheterization, for example, to pinpoint the exact location of a Fontan leak or a pulmonary arterial– venous connection. Transpulmonary Contrast Echocardiography Principle Unlike agitated saline, commercially available transpulmonary contrast agents consist of a suspension of microspheres designed to pass through the pulmonary capillary bed and densely opacify the left heart structures (90). These microspheres are 10-fold smaller than the microbubbles created with saline agitation (1 to 10 μ vs. The microspheres consist of an internal gas (air or fluorocarbon) encapsulated by an external shell (albumin or lipid). After an intravenous injection, the microspheres will follow the downstream course of the blood into the right heart and pulmonary vasculature. The microspheres are sufficiently small and the diffusion of the inert gas is sufficiently limited by its low partition coefficient that the microspheres pass through the capillary bed into the left heart. Because the acoustic impedance of the microspheres is much lower than that of the blood, the ultrasound waves are scattered and reflected at the microsphere–blood interface. Indications Currently, contrast agents are approved for the use of heart opacification and endocardial visualization only. Therefore, they are indicated when traditional echocardiographic modalities yield suboptimal myocardial and endocardial visualization such as during exercise echocardiography when visualization of all myocardial segments is required (91,92) or in the evaluation of right ventricular function since right ventricular endocardium and myocardium can be very difficult to visualize. In adults, adverse reactions are extremely rare and consist of allergic reaction, headache, flushing, and nausea. In the presence of an intracardiac shunt, the microspheres can bypass filtering by the lung and enter the arterial circulation directly. It is believed that the larger (up to 32 μ) microspheres which constitute a very small percentage of the total suspension and which are normally filtered by the lungs can pass into the left heart and produce arterial occlusions in this setting. Therefore, no transpulmonary contrast agent should ever be administered to a patient with a known or suspected intracardiac shunt. Research Echocardiography Because of its ease of use, portability, low cost, absence of side effects, and high diagnostic accuracy; echocardiography is a robust research tool. Echocardiography has been successfully used to provide mechanistic insights on disease processes and therapeutic outcomes, to provide both cross-sectional and longitudinal data in large epidemiologic studies, to phenotype probands and their relatives in genotyping studies, and to measure functional and structural changes now considered to be end points (93). The Framingham Heart Study was the first epidemiologic study to use echocardiographic measurements (94). The single largest application of echocardiography in epidemiologic studies has been the measurement of left ventricular mass and its change with antihypertensive therapy (95,96,97,98,99).