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Distribution of third These were the first reports of the diagnostic utility of occipital headache discount propranolol online mastercard blood pressure chart low bp. Note overlapping pain referral from C0-C1 discount propranolol online mastercard blood pressure medication causing heart palpitations, C1-C2 anesthetizing the medial branch of the C3 dorsal ramus cheap propranolol 80mg with mastercard blood pressure chart india. Epidemiologic data indicated that cervicogenic head- ache most often stems from C2-C3 facet joint. In clinical trials, it has been demon- pain-referral patterns from cervical facet joints. Using strated that anesthetic blockade of the third occipital nerve normal volunteers, Dwyer et al. The segmental pain-referral patterns produced With a prevalence of 54% facet joint pain, the joints most coincided with those of Bogduk and Marsland’s study. In a double-blind, mance of a C2-C3 facet injection will be described in this randomly assisted study (between 2000 and 2004), patients chapter for its potential applications. Segmentally, the respective positive rates at C2-C3 and percentage of pain relief (80–90% or greater) are confirma- C1-C2 were 72% and 56%. However, these new data recommend that Radiofrequency Neurotomy C3-C4 should be after the C1-C2 joint has been investi- Several descriptive and long-term reports describing the gated, which is a technically more demanding procedure. In a appeared in the literature from the late 1970s into the report published in 2004, Stovner et al. They blocks, and use of surgical technique not accurately target- concluded that this procedure is probably not an effective ing the cervical medial branches. It was concluded that The following year, Lord and colleagues109 reported that a near 100% pain relief response should “probably” be chronic neck pain below the C2-C3 facet had been effectively among the inclusion criteria in such studies. When blocks were used, they were Initial attempts to provide similar long-term results in only used in such a way as to predict or validate the out- patients suffering from third occipital headache produced comes based on clinical findings. Patients with- took many factors into consideration, including the variable out complete relief were enrolled in a controlled trial; pathways of the third occipital nerve, published data that therefore, under those conditions the trial was designed yielded long-term results similar to those demonstrated to show no efficacy. The The receptor fields are large, and one or two nerve study predictably demonstrated that patients who did not endings may be sufficient to monitor the area of each facet respond to diagnostic blocks did not respond to medial capsule. This could have impor- lustrate their technique, leaving open the question as to tant implications for long-term joint function. Descrip- Because the C2-C3 joint is innervated mainly by the tions of the surgical technique included that the patient was large third occipital nerve and small communicating placed in the supine position. In addition, 22-gauge needles branches that originate from the second cervical nerve, with 50-mm electrode lengths were employed upon utiliz- third occipital nerve blockade is sufficient to establish the ing stimulation as a criterion for accurate nerve localiza- diagnosis of C2-C3 facet pain. Only three to four parallel lesions against a single also provides cutaneous neural supply to the suboccipital plane (sagittal or oblique) were performed at 60 seconds. He additionally raised concerns the dorsal branches of C1, C2, and C3, which may also that this study could be misused to discredit the already play a role in the anatomic basis for cervicogenic head- vindicated practice as described in those guidelines. The third occipital nerve is the only nerve to cross the facet joint and gives off gon c articular branches to the C2-C3 facet joint from its deeper surface. In experimental studies m with normal human volunteers, referred pain from the 88 s C2-C3 joint was perceived in the head. The dorsal ramus divides into two medial branches and a lateral branch that innervates the superficial muscles. The innervation of the C2-C3 facet joint primarily is from the large, superficial medial branch of the C3 spinal nerve, the third occipital nerve. These in- occipital nerve block is to determine if the patient’s pain is clude potential leakage and subsequent spread of injected mediated by that nerve. The only validated treatment for local anesthetic into the epidural space, thereby render- pain mediated by the third occipital nerve is percutaneous ing it useless in terms of target specificity. If the possibility of the size and variability of course of the third occipital using this treatment is being entertained, dual controlled nerve requires that anesthetization of the nerve using blocks are a prerequisite. Misguided treatment anesthetizing the nerve is essential and false-positive, as of headaches of unknown origin may lead to disastrous well as false-negative responses must be kept to a mini- consequences for the patient. The only method of validating that the patient’s tablishing a correct diagnosis prolong the patient’s suffering, pain is mediated by the third occipital nerve is by the use but it may also lead to long-term physical, medical, and sur- of dual control blocks. Distention or ■ Systemic infection or localized infection at the stressing the joint capsule by joint arthrography may repro- puncture site. By doing so, the prac- ■ Any anatomical derangements, surgical or congeni- titioner may find that an overlooked diagnosis or other tal, that would preclude safe, successful access. Patients displaying psychiat- ■ Patients who have had inadequate pain relief or ric disturbances (severe), symptom magnification, history relief for less than 3 months following a previous of substance and alcohol abuse, multiple emergency room neurotomy. Diagnostic criteria supplied by the Cervicogenic Headache International Study Group pro- vide a detailed description of the condition. Controlled diagnostic blocks constitute and presence of mechanical precipitation mechanisms. Essentially, this is unilateral (very rarely bilateral) termine if headache is the dominant complaint. If so, all pain that can be exacerbated by palpation over the C2-C3 other forms of headache must be ruled out before set- facet joint. Axial loading, including rotation and bending tling on a diagnosis of third occipital headache, includ- toward the ipsilateral side, may further intensify symptoms. Pain from the C2-C3 joint is flag” conditions such as tumor, metastatic disease, infec- located in the upper cervical region and extends at least to tion, and metabolic process. Therefore, the Although the physical examination may be quite use- reader must be familiar with the characteristics of head- ful in leading toward a specific diagnosis, there is fre- quently overlap of pain referral patterns. Because of this overlap of pain As time passes, it becomes more difficult to deter- referral patterns, nerve infiltration with local anesthetic is mine whether previous interventions have failed because mandatory in establishing a diagnosis. Thus, the headache patient who The reader is encouraged to become familiar with has had a series of medical and surgical failures can easily algorithms for cervical synovial joint blocks, as well as the be mislabeled as malingering, suffering from chemical headache algorithm recently set forth by the International Spine Intervention Society. The C-arm can be adjusted to open the joint using a slight craniocaudal an- Candidates for third occipital nerve block must be fully in- gulation. The consent should be properly witnessed, and all questions from the patient answered in full prior to proceeding. Patients must also understand their responsibility Sedation is not required for either the C2-C3 intra-articular to keep an accurate postprocedure pain diary. Minimal sedatives may be used if C2-C3 Intra-Articular Facet Injection/Third Occipital Nerve required to combat excessive anxiety. Administration of Block narcotics will confound interpretation of the percentage of pain relief, and therefore are contraindicated. With the patient in the prone, supine, or lateral position, the C-arm must be oriented to ensure a true lateral image. The C2-C3 joint must be clearly visualized with the The prone position allows greater stability for the cervi- silhouettes of the articular pillars superimposed providing cal spine, with a foam wedge placed under the patient’s a sharp, crisp image. Errors in anatomic visualization, tar- chest and head flexed with nasal cannulae or a jelly get identification, needle placement, and performance of doughnut. The injection can also be performed in the lateral The lateral flange of the inferior articular process position, but patient cooperation is critical for consistent of C2 usually overlaps the C2-C3 joint, so a direct lateral radiographic imaging without moving the C-arm via pa- approach is usually not possible. Typically, only 1/16 ml of contrast is required to confirm intracapsular placement.

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Accurate placement of individual excessive transatrial right ventricular muscle resection propranolol 80 mg without prescription blood pressure medication helps acne. Any injury to the coronary artery must be posterior leaflet and midway below the common anterior carefully evaluated buy 80 mg propranolol visa blood pressure medication chronic cough, with serious consideration given to per- leaflet buy generic propranolol 80 mg on-line heart attack buck. Strategic retraction of the anterior common leaflet forming a bypass from the internal thoracic artery to the will allow secure suture placement into the subaortic conus coronary artery. Occasionally, a limited right monary artery is the best alternative that preserves the course of ventriculotomy will be required in order to place the subaor- the coronary artery. When the time comes to consider conduit tic sutures, owing to exposure limitations from the right replacement, consideration should be given to enlarging the atrium. Such a condition may preclude conduit replacement in petency of the atrioventricular valves is carefully considered. Though the left atrioventricular valve is the main focus of attention in patients with a simple atrioventricular canal, conscientious repair of the right atrioventricular valve in 12. Pulmonary valve preserva- approach to this set of lesions is early transventricular tetral- tion strategies for tetralogy of Fallot repair. Oper Tech ogy repair, pulmonary artery reduction arterioplasty, and a Thorac Cardiovasc Surg. The principles of transventricular repair are essen- tially the same as for tetralogy of Fallot and truncus Figs. World J Pediatr Congenit duit from the right ventricle to the pulmonary artery, as a Heart Surg. The right sis owing to poor mixing and often requires a transcatheter atrial suture line represents the atrial entry for patent fora- balloon atrial septostomy to stabilize the hemodynamic men ovale or atrial septal defect closure. Often, a running suture monary artery shunt is placed, followed by a Rastelli technique (Fig. Optimal cardioplegia strategies will ensure myocardial protection during this time. Mavroudis are performed to transfer the coronary artery buttons to the with coronary artery kinking and neoaortic regurgitation respective sinus of Valsalva to complete the proximal neo- from anastomotic malrotation and mismatch. Occasionally, however, the surgeon recognizes which will avoid tension or kinking at the coronary anas- poor apposition of the suture line, especially in the area of tomosis. The localized pulmonary artery at the respective the coronary artery button anchoring stitch. The rest of the anastomosis is button anastomosis being commenced at the center point of performed with these tenets in mind (Fig. Some surgeons airing maneuvers are performed in tandem with release of prefer to rotate the coronary button to achieve a “best lie” the cross clamp before the final tie is completed (Fig. The operating surgeon should decide on the The patient can now be rewarmed during the neopulmo- best anatomic arrangement to optimize flow after reconstruc- nary artery reconstruction. The suture line is usually commenced with 8–0 running mal aorta, soon to become the neopulmonary artery, with monofilament suture on one side (Fig. Individual sutures at the top of the anas- pericardium is incised centrally to construct a pantaloon tomosis are used to anchor the running suture. The surgeon patch that, when sutured appropriately, will fill out the dis- should know which suture represents the running suture that sected sinuses of Valsalva. The suture is placed at the apex was used for the anastomosis and which suture represents of the incised pericardium and approximated to the apex of the anchoring suture placed at the top of the anastomosis. Running suture technique (with this way, the surgeon will know whether to redo the entire 7–0 monofilament suture) is used for this reconstruction. Once this step is finished, the very important entire anastomosis may need to be redone to avoid unwanted tapering of the pericardial patch is performed, following unraveling. First, the posterior portion of the pericar- being prepared for coronary transfer by local wall resec- dial patch is intentionally left approximately 3–4 mm lon- tion. The same suturing technique is applied to this sinus ger, to decrease any chances of coronary artery compression (Fig. The pulmonary favorable match between the neopulmonary artery and the artery is brought anterior to the ascending aorta (Fig. Secondly, the patch is diately posterior to the newly positioned ascending aorta cut in a semicircular, crescent-shaped configuration, not in (Fig. The aortic cross clamp is now released, because a straight line from commissure to commissure. This the ascending aorta is controlled by the forceps, and placed maneuver ensures redundant neosinuses of Valsalva on the ascending aorta inferior and posterior to the ascending (Fig. The arch repair therefore will require complete 1 and the left hand signifies Sinus 2. In this manner, all types ductus arteriosus removal, posterior suture reconstruction, of configurations can be noted by simply describing which and anterior patch augmentation to bring the patch into the coronaries arise from each of the sinuses. This technique can account for inverted coronary arteries, single coronary allows for an enlarged outflow tract reconstruction and a arteries, and intramural coronary arteries with simple more favorable anastomosis with the proximal neoaortic descriptions. Cardiopulmonary bypass techniques (dual require careful intraoperative diagnosis, establishing appro- arterial cannulation, regional perfusion, deep hypothermia, priate cardioplegic techniques consistent with the anticipated and circulatory arrest), cardioplegia administration, and longer cross-clamp time that may involve retrograde cardio- suturing strategies will guide the surgeon to complete this plegia or intracoronary administration, and extensive mobili- challenging operation. Small pericardial patches may also be necessary, especially for single coronary artery buttons, which cannot be trans- ferred easily. In addition, the left main coronary artery has an intra- mural route that courses across the commissure into Sinus 1, where it emerges as the left main coronary artery. The surgeon views the anatomy from the head down— the reverse of the anatomist’s conventional view of the anatomy from the feet up. Before any incisions are made, the surgeon must decide whether there is enough room between the orifices of the two coronary arteries to form two distinct buttons. The mobilization of this coronary but- ton is less complex than the left main coronary button. The remaining coronary button must be separated from the aortic wall and the posterior commissure where the leaflets are attached. This separation is performed by sharp dissection and mobilizing the commissural attachment with a portion of the aortic wall to allow for eventual reconstruction (Fig. The intramural segment is then unroofed and tacking sutures are placed at the neo-orifice to ensure the integrity of the orifice and to avoid dissection and occlusion (Fig. The artery is then mobilized with careful, low- setting electrocautery techniques (Fig. In this set of drawings, the intramural course of the coronary artery is unroofed. In times past, unroofing was not always per- formed, owing to fear of disruption and dissection, but cur- rently the wisdom is always to unroof the course of the 13 Transposition of the Great Arteries 175 intramural artery to avoid problems in the future. Oftentimes, the proximal neoaortic reconstruc- Such is the case with a single coronary artery origin from tion is much larger than the distal aorta, especially when the Sinus 2 as shown in Figure 13. The dotted lines depict the coronary buttons are anomalous and require more space for area of dissection and separation from the aorta and the area reimplantation. Under these circumstances, the ascending of reimplantation into the pulmonary artery, soon to become aorta can be enlarged by linear incision and pericardial patch the neoaorta. An acceptable alternative to The neopulmonary artery reconstruction is commenced this situation is to mobilize the branches of both coronary with the pericardial patch, which, in this case, is not cut arteries and rotate the coronary artery button 90° (Fig. A piece of pericardium can then be used to cre- of the remaining neopulmonary artery wall in anticipation ate a hood, thereby ensuring a patent, nonobstructed pathway of commissural reattachment to the implanted pericardium to the coronary arteries (Figs.

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After a high-energy positron is emitted from a nucleus buy propranolol paypal blood pressure normal high, it travels a few millimeters in tissue and ultimately collides with an electron (a negatively charged beta particle) buy propranolol 80 mg otc hypertension 140. This collision results in complete annihilation of both the positron and the electron cheap propranolol online american express pulse pressure compliance, with conversion to energy in the form of electromagnetic radiation composed of two high-energy gamma rays, each with 511-keV energy. The discharged gamma rays travel in perfectly opposite directions (180 degrees from each other). If the data are acquired in dynamic mode, with appropriate mathematical modeling, myocardial perfusion and metabolic data can be displayed in absolute terms: in milliliters per gram per minute for blood flow and moles per gram per minute for metabolism. The rapid physiologic washout of the 15 freely diffusible tracers, such as O-water, makes it possible to repeat studies in rapid sequence. The images of the distribution of such tracers are usually not visually meaningful; mathematical modeling is done to arrive at flow values at each pixel. An advantage of freely diffusible tracers is that they do not depend on a metabolic trapping mechanism, which might change as a function of a changing metabolic environment. The nondiffusible flow tracers are easier to image, because the tracer is retained in myocardium for a 82 13 reasonable length of time. Rb and N-ammonia fall into this second category of flow tracers, the more 82 microsphere-like flow tracers. In experimental studies, its extraction fraction does not change significantly over a wide range of 82 metabolic conditions. However, the very short half-life of 75 seconds for Rb means that any trapped 82 82 Rb quickly disappears from the myocardium by physical decay. Despite its short half-life, Rb is easily obtained, because it is generator produced, and it can be used clinically without the need for an on-site cyclotron. Its transport + + across cell membranes may occur by passive diffusion or by the active Na -K transport mechanism. As with Rb, myocardial uptake of ammonia reflects absolute blood flows up to 2 to 3 mL/g/min and plateaus at more hyperemic flows. The use of this tracer to assess myocardial blood flow has been extensively validated in both 9 experimental and clinical studies. B, Paired stress and rest images show extensive reversible regional perfusion defects in all three coronary artery vascular territories: inferior wall reversible defect (white arrows), lateral wall reversible defect (arrowheads), and anteroseptal wall reversible defect (yellow arrows). Journey in evolution of nuclear cardiology: will there be another quantum leap with the F- 18 labeled myocardial perfusion tracers? As such, the addition of the quantitative analysis of perfusion reserves suggests three-vessel disease instead of the single-vessel disease suggested by the standard analysis of relative distribution of flow. Quantitative blood flow approaches offer an objective interpretation that is inherently more reproducible than visual analysis. Absolute quantification may aid in assessing the physiologic significance of known coronary artery stenosis, especially when of intermediate severity. Tracers for these applications are discussed in detail later (see Assessment of Myocardial Cellular Metabolism and Physiology). The advantage afforded by the combined scanner is that the corresponding images are spatially aligned and can be acquired during a single imaging session (eFig. Red lines represent planes for cross-sectional views of coronary arteries (not shown). Methods using respiratory gating to correct this problem are currently under investigation. The incremental radiation dose from performing two diagnostic studies also should be considered. The latter may have important implications for aggressive risk factor modification and medical therapy. All other applications, such as detection of endothelial dysfunction or microvascular disease and identification of soft plaques, remain experimental at this time, with limited clinical data to support widespread clinical application. Radiation Exposure Issues Clinical decision making for the use of low-level ionizing radiation to obtain diagnostic nuclear cardiac studies must adhere to appropriate use criteria and encompass the broad range of the risk-benefit ratio, with the guiding principle to minimize exposure while obtaining the necessary high-quality diagnostic information. The prediction of risk of subsequent malignant transformation for an individual undergoing a medical diagnostic test or procedure employing ionizing radiation is a complex exercise with many uncertainties. Concerns about the late carcinogenic effects of exposure to low levels (<100 mSv) of ionizing radiation stem from extrapolation of exposure outcome data in survivors of atomic bomb explosions. Uncertainty remains, however, regarding the dose-response relationship in the lower range of exposure, adding complexity to assessment of the incremental risk to patients, as well as of tissue- 20 specific reparative responses that also may be manifested at lower levels of exposure. Nonetheless, exposure of the patient to ionizing radiation should be at the minimum dose consistent with obtaining a diagnostic examination. Each procedure is unique, and the methodology to achieve minimum exposure while maintaining diagnostic accuracy needs to be viewed in this light to ensure optimal patient care. Thus the uptake and retention of these tracers do reflect regional flow differences, but myocyte cell membrane integrity also is a prerequisite. Visualization of myocardial regions suggests the presence of working, viable cell membranes, but lack of visualization of myocardium does not necessarily indicate the absence of viable cells. Decreased regional myocardial tracer uptake at rest could reflect either lack of cell membrane integrity in an area of infarcted myocardium or reduced blood flow secondary to hibernating but viable myocardium. In these patients, techniques that 201 assess intact cellular metabolic processes (e. In both studies, the severity of the defect suggests minimal myocyte viability within those territories. Assessment of Infarct Size 99m 21 Contemporary studies have used Tc-sestamibi to provide an assessment of infarct size. Because clearance from the myocardium after initial uptake of this tracer is minimal, images acquired even hours after initial injection represent a “snapshot” of blood flow conditions and tracer uptake at the time of injection. Infarct size as assessed by quantitative analysis of rest sestamibi uptake has been validated against 21 many other measures of infarct size. The change in defect size between the initial image acquired in the acute stage and the later image represents the magnitude of salvaged myocardium from reperfusion. Assessment of Myocardial Perfusion During Stress Coronary blood flow must respond rapidly to changing metabolic conditions and oxygen demand to meet the nutrient needs of myocytes being called on to contract more frequently and with more force. Oxygen extraction by the myocardium is nearly maximum at rest; thus any increase in oxygen demand can be met only through increasing coronary blood flow to deliver more oxygen per unit time (see Chapter 57). The major determinants of coronary blood flow include the perfusion pressure at the head of the system (principally aortic diastolic pressure) and the downstream resistance, residing predominantly in the coronary arteriolar bed. Because aortic diastolic pressure during exercise varies little from the value at rest, the major mechanism responsible for increasing coronary blood flow during stress involves a reduction in coronary vascular resistance. During exercise stress, coronary blood flow can increase approximately two to three times above levels at rest. During pharmacologic stress to minimize coronary arteriolar resistance, using intravenous coronary arteriolar vasodilator agents such as dipyridamole, adenosine, or regadenoson (discussed later), coronary blood flow can increase up to four to five times above rest levels.

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Vegetations appear as discrete echogenic masses that are adherent to but distinct from the leaflet itself cheap 40 mg propranolol fast delivery blood pressure chart age 13. Characteristics of vegetations that aid in distinguishing them from other masses include localization order propranolol with mastercard hypertensive urgency treatment, texture cheap propranolol 40 mg without prescription arrhythmia quiz, motion, shape, and associated abnormalities. Vegetations are typically located on the upstream, or low-pressure, side of the valve, in the path of any regurgitant bloodstream (i. The echodensity of a vegetation is usually similar to that of myocardium, although advanced vegetations can be inhomogeneous, with findings indicative of liquefaction (which is echolucent) or calcification (which is echodense or bright). Large vegetations can prolapse into the upstream chamber and create a “ball-and-chain” effect that causes leaflet flail and regurgitation. Vegetations vary tremendously in shape but often appear as compact multilobulated or pedunculated, amorphous, and friable agglomerations compared with tumor tissue or thrombus. The vegetation can extend some distance from the valve to which it is tethered and may occur in multiples on the same or different valves. Associated abnormalities such as regurgitation, abscesses, and intracardiac channels can accompany advanced endocarditis. There are no distinguishing characteristics that are organism specific, although staphylococcal infections (particularly methicillin-resistant Staphylococcus aureus and S. Vegetations devoid of microorganisms are the hallmark of noninfectious endocarditis, also called “nonbacterial thrombotic” or “nonbacterial marantic” endocarditis (see Chapter 73). The typical lesions are small (1 to 5 mm), verrucous, nondestructive nodules that adhere to the upstream side of the valve (typically mitral or aortic) along the line of closure and contain only cellular and fibrin elements. These also occur in patients with advanced neoplasms, sepsis, and prothrombotic tendencies in association with 78 clinical features indistinguishable from those of typical infective endocarditis (see later, Systemic Diseases and Echocardiography). Of note, the presence of preexisting thickening and degenerative changes in leaflets can render the diagnosis challenging. On occasion, myxomatous leaflets, ruptured chordae, calcified structures, and fibrin strands can either mask or mimic a vegetation. In these circumstances, clinical correlation with other Duke diagnostic criteria is important. Comparison with previous echocardiograms should also be undertaken; a stable finding over years is unlikely to represent a vegetation. Among patients with endocarditis, 66% to 75% have risk factors for infection, and echocardiography should be used to scrutinize the relevant structures at risk especially carefully. Patients with prosthetic valves, complex cyanotic congenital heart disease, surgical systemic-pulmonary shunts, bicuspid aortic valves, rheumatic heart disease, or mitral valve prolapse are at higher risk. Echocardiographic characteristics associated with a poorer prognosis and embolization include vegetation size greater than 1. The natural history of vegetations after medical therapy is of interest because most will still be apparent on follow-up echocardiography in 1 to 2 months, even after successful medical treatment. These observations probably reflect the varied components of the vegetation, which include not only bacteria but also inflammatory cells, fibroblasts, and extracellular matrix. Growth of a vegetation over time and increasing valvular regurgitation are poor prognostic signs. However, the mere persistence of vegetations in the absence of symptoms or positive blood cultures is not associated with increased clinical complications. Thus, treatment of endocarditis should not be guided by the echocardiographic morphology of the vegetation over time but by clinical response to therapy. If present, these vegetations are indications for surgery, particularly if recalcitrant to medical therapy. Indications include (1) embolism to the coronary arteries, brain, lungs, spleen, kidney, or extremities; (2) severe valvular regurgitation and heart failure secondary to leaflet malcoaptation, perforations, or flail; (3) abscess, which may invade the cardiac conduction system; (4) mycotic aneurysms of vessels and valves; (5) pseudoaneurysms or fistulas of the heart; and (6) suppurative or hemorrhagic pericarditis. On the aortic valve, involvement of the right cusp can lead to necrosis of the membranous interventricular septum, aneurysm of the right sinus of Valsalva, and valve dehiscence. Involvement of the left cusp can affect the intervalvular fibrosa and extend to infect the base of the anterior mitral valve leaflet. Involvement of the noncoronary cusp can extend to the posterior interventricular septum, where the His conduction fibers are located, which can lead to the development of an intra- or infrahisian block (third-degree atrioventricular block) or bundle branch block. Severe infection of the mitral valve less frequently leads to conduction disturbances. Although first- or second-degree atrioventricular block can occur, supraventricular tachycardias are more common. Tricuspid valve infection can extend to involve the tricuspid annulus and eustachian valves (Fig. Systemic Diseases and Echocardiography Aside from conditions that directly affect the heart itself, many systemic diseases with cardiac manifestations are detectable on echocardiography. Renal disease causes early calcification of the valves and potentially uremic pericardial effusions. Amyloidosis is notorious for causing restrictive cardiomyopathy (see earlier and Fig. Infiltration of amyloid into the atrial walls leads to poor atrial contractility and 47 a high prevalence of atrial thrombi, even when sinus rhythm is still present. Granulomatous diseases such as sarcoidosis can cause a focal myocarditis with granulomas (eFig. Pericarditis, valvulitis, and coronary and aortic arteritis have also been reported with Wegener granulomatosis. Although scleroderma is known to cause direct myocardial fibrosis histologically, on echocardiography this becomes apparent in only a minority of patients, usually late in the course of disease. A, Apical four-chamber view illustrating the right-sided heart enlargement (containing a pacemaker wire) and the septal focal wall motion abnormalities in the left ventricle (“scalloping”) typically seen in sarcoid heart disease. Similarly, even when cancers spare the heart, the radiation and chemotherapy regimens used to attack the neoplasms can have cardiac effects (see Chapter 81). Ideally, the early detection of cardiomyopathy in patients who receive chemotherapy, particularly with anthracyclines (as well as tyrosine kinase inhibitors and immunomodulators), allows modification of the protocol before irreversible damage occurs. Several other conditions predispose to valvular abnormalities (see earlier, Valvular Heart Disease). Rheumatic carditis and its sequelae are well-known historical examples and are still a significant cause of heart disease in developing nations (see Chapter 74). More than 50% of patients with carcinoid tumors have cardiac involvement in which plaquelike deposits build up on the right-sided heart valves (typically the ventricular aspect of the tricuspid valve and the arterial aspect of the pulmonic valve). This causes a characteristic retracted and fixed appearance of the tricuspid and pulmonary leaflets and a combination of valvular stenosis and regurgitation (see Fig. Pulmonary Hypertension Echocardiography can assess for pulmonary hypertension and causative conditions. In the absence of known pulmonary disease, the presence of an enlarged right side of the heart with a normal-appearing left ventricle prompt a search for secondary causes of pulmonary hypertension (Fig.