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The presence of refractory congestive heart failure order mebendazole 100mg free shipping hiv infection no antibodies, recurrent systemic embolization purchase 100mg mebendazole symptoms of recent hiv infection, acute aortic valve leaflet tear mebendazole 100mg with mastercard natural factors antiviral echinamide, and evidence of a paravalvular aortic root abscess demand immediate surgery generic mebendazole 100mg antiretroviral used for hiv. Patients with infective endocarditis of the aortic valve who become surgical candidates often have multiorgan system deficiencies. They are frequently in heart failure, have ongoing sepsis, renal insufficiency, and many have evidence of a recent stroke due to septic emboli. Optimum myocardial protection is crucial in these compromised patients to allow for adequate time to completely remove all infected material, reconstruct the aortic root, and achieve a competent aortic valve. Dislodgement of Vegetations the antegrade infusion of cardioplegia into the aortic root under high pressure may dislodge and break up large vegetations that can embolize into the coronary arteries. The aorta is opened and cardioplegic solution is administered into the coronary arteries under direct vision. Cross Contamination To reduce the possibility of recurrence of endocarditis, every effort should be made to prevent cross contamination. This entails changing gloves, local drapes, and surgical instruments used to remove the infected material from the operative field. Complete Debridement the most crucial aspect of the procedure is the complete debridement of all the infected tissues, even if that entails the resection of the entire aortic root and adjacent tissues. In areas where the aortic annulus is destroyed, the left ventricular outflow tract and the aorta are reapproximated with a patch of glutaraldehyde-treated autologous pericardium or bovine pericardium. At times, it may be necessary to create a new annulus by sandwiching the aorta and left ventricular outflow tract with two strips of pericardium. Subannular Necrotic Cavities Removal of necrotic tissue from the subannular area can create small cavities. Following radical debridement, it may be difficult to reestablish continuity between the aorta and left ventricular outflow tract. An effective technique is to replace the aortic root with either an aortic homograft or a stentless bioprosthesis as described in the preceding text. Use of Pulmonary Autograft Although many surgeons are reluctant to perform a Ross procedure in the face of aortic endocarditis for fear of introducing infection into the right ventricular outflow tract, the pulmonary autograft is another replacement option in younger patients with endocarditis. Some of the predisposing factors, such as a calcified or infected annulus (which allows the sutures to cut through the tissues), have been discussed previously. Paravalvular leaks tend to occur more commonly along the noncoronary annulus and the adjacent half of the left coronary annulus. Massive calcification affecting the aortomitral leaflet continuity may obscure the annulus and interfere with correct placement of anchoring stitches. Attention to these details when performing aortic valve replacement helps prevent late paravalvular leaks. Pledgeted sutures are passed deeply through the tissue margin of the defect and then through the sewing ring of the prosthesis before tying. When the integrity of the tissue margin of the defect is not satisfactory, sutures are passed through the sewing ring of the prosthesis before taking a deep bite near the annulus through the full thickness of the aortic wall to the outside of the aorta. When there are multiple paravalvular leaks or the site of the leak is not obvious, it is necessary to explant the prosthesis and implant a new one, ensuring that all the valve sutures bites incorporate healthy tissues. Interventional Closure of Periprosthetic Leaks Recently, some institutions have closed paravalvular defects with an atrial septal defect or ductal occluder device in the catheterization laboratory. Patients must have severe calcific aortic stenosis (regardless of pressure gradients), have a life expectancy of at least one year, and be high risk for surgical valve replacement. Multimodality imaging of the aortic root is required to evaluate annular size, coronary height, and calcification. Other issues such as presence of left ventricular thrombus, bicuspid aortic valve, ventricular aneurysm, subaortic stenosis, and endocarditis are also assessed. In general, aortic annulus sizes less than 19 mm or greater than 31 mm are regarded as relative contraindications for the use of currently available commercial devices. Imaging of the entire aorta, iliacs, and femoral vessels is required to evaluate the vascular access required for delivery sheath insertion. While first-generation devices were 24 French and required large caliber, newer expandable sheaths (14 French) now accommodate vessels as small as 6 mm depending on the extent of calcification. These involve dissection of the iliac and femoral arteries and less commonly, avulsion and massive hemorrhage. While the recommended minimal luminal diameter for the femoral vessels is 7-8 mm depending on valve size, the extent of vascular calcification and tortuosity impact the incidence of these complications. Femoral arterial access is obtained in both groins and the larger artery is used to insert the delivery sheath (18 to 24 French), while the other is accessed with a 5 French sheath for delivery of the pigtail catheter. After the introduction of a long sheath into the descending aorta, a stiff wire with a floppy tip is used to enter the ascending aorta and the root. Now the valve is crossed and the stiff wire is inserted into the left ventricle through the long sheath. At this point, an appropriately sized valve is mounted on the delivery system and advanced over the stiff wire with the end in the left ventricle. Appropriate images of the aortic root are critical with the nadir of all sinuses being visible during a root injection through the pigtail. An aortogram combined with echocardiography and hemodynamic measurements should be used to assess the function of the valve with particular attention to paravalvular leaks. Once satisfactory function of the valve is confirmed, wires are withdrawn and the femoral vessels closed as appropriate. Sheath Removal Removal of the large sheath should be done over a wire that is retained and in the presence of contralateral access in case of a vascular injury. For the transapical technique, it is important to identify a safe area of cannulation lateral to the true apex of the heart. Finger pressure and echocardiography are used to identify a suitable are that is in line with the aortic valve for deployment. Two concentric purse-strings with large felt pledgets are used to secure the myocardium around a 26 French sheath that is introduced after serial dilations. Weak Myocardial tissue In cases of a fragile myocardium or redo operations, the ventricular purse-strings should incorporate the native pericardium to provide more structural support. Cardioplumonary support In patients with significant pulmonary hypertension, poor ventricular function or those with untreated significant coronary arterial lesions, rapid access to cardiopulmonary bypass and circulatory support through the femoral vessels should be available. These complications may be managed by percutaneous drains and reversal of coagulopathy but may eventually require open surgical repair. The strategy to rectify a malpositioned valve depends on the site, hemodynamic stability of the patient, and overall risk. Coronary obstruction can occur in the presence of bulky calcium on the native leaflets, a distance of <10 mm from the coronary ostia to the annulus and shallow aortic sinuses. However, emergent hemodynamic support via cardiopulmonary bypass and even surgical revascularization may be required as deemed necessary by the team. As the population ages, surgeons are seeing more patients with mitral insufficiency secondary to calcific mitral valve diseases.

Syndromes

  • Do NOT use cold baths, ice, or alcohol rubs. These often make the situation worse by causing shivering.
  • Disorders of the adrenal gland (such as pheochromocytoma or Cushing syndrome)
  • Molluscum contagiosum
  • Medicines to control vomiting
  • Amount swallowed
  • Immediate kidney dialysis
  • Bleeding inside the head or a stroke
  • Drugs added to a blood sample to check for damage to chromosomes
  • Leakage of blood through the valve back into the heart
  • Do you have nervous habits that include hair pulling or scalp rubbing?

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Monnet X generic mebendazole 100mg amex antiviral warning, Rienzo M generic mebendazole 100 mg free shipping hiv infection youth, Osman D buy 100 mg mebendazole with visa hiv infection with no symptoms, et al: Esophageal Doppler monitoring predicts fluid responsiveness in critically ill ventilated patients discount 100mg mebendazole amex antiviral infection. Lafanechere A, Pene F, Goulenok C, et al: Changes in aortic blood flow induced by passive leg raising predict fluid responsiveness in critically ill patients. Monnet X, Rienzo M, Osman D, et al: Passive leg raising predicts fluid responsiveness in the critically ill. Soubrier S, Saulnier F, Hubert H, et al: Can dynamic indicators help the prediction of fluid responsiveness in spontaneously breathing critically ill patients? Chytra I, Pradl R, Bosman R, et al: Esophageal Doppler-guided fluid management decreases blood lactate levels in multiple-trauma patients: a randomized controlled trial. Singer M: Esophageal Doppler monitoring of aortic blood flow: beat- by-beat cardiac output monitoring. Rivers E, Nguyen B, Havstad S, et al: Early goal-directed therapy in the treatment of severe sepsis and septic shock. Vieillard-Baron A, Slama M, Mayo P, et al: A pilot study on safety and clinical utility of a single-use 72-hour indwelling transesophageal echocardiography probe. Wellen- und windkesselthrorie Estimation of the strok volume of the human heart using the “windkessel” theory [in German]. Wesseling K, de Wit Bd, Weber J, et al: A simple device for the continuous measurement of cardiac output. Mielck F, Buhre W, Hanekop G, et al: Comparison of continuous cardiac output measurements in patients after cardiac surgery. Rauch H, Muller M, Fleischer F, et al: Pulse contour analysis versus thermodilution in cardiac surgery patients. De Backer D, Marx G, Tan A, et al: Arterial pressure-based cardiac output monitoring: a multicenter validation of the third-generation software in septic patients. Osman D, Ridel C, Ray P, et al: Cardiac filling pressures are not appropriate to predict hemodynamic response to volume challenge. Michard F, Alaya S, Zarka V, et al: Global end-diastolic volume as an indicator of cardiac preload in patients with septic shock. Jozwiak M, Silva S, Persichini R, et al: Extravascular lung water is an independent prognostic factor in patients with acute respiratory distress syndrome. Krejci V, Vannucci A, Abbas A, et al: Comparison of calibrated and uncalibrated arterial pressure-based cardiac output monitors during orthotopic liver transplantation. Marque S, Gros A, Chimot L, et al: Cardiac output monitoring in septic shock: evaluation of the third-generation Flotrac-Vigileo. De Backer D, Heenen S, Piagnerelli M, et al: Pulse pressure variations to predict fluid responsiveness: influence of tidal volume. Keren H, Burkhoff D, Squara P: Evaluation of a noninvasive continuous cardiac output monitoring system based on thoracic bioreactance. Benomar B, Ouattara A, Estagnasie P, et al: Fluid responsiveness predicted by noninvasive bioreactance-based passive leg raise test. Tong H, Hu C, Hao X, et al: the prediction value of noninvasive bioreactance-based passive leg raising test in assessing fluid responsiveness in elderly patients with sepsis[in Chinese]. Maizel J, Airapetian N, Lorne E, et al: Diagnosis of central hypovolemia by using passive leg raising. Gutierrez G, Palizas F, Doglio G, et al: Gastric intramucosal pH as a therapeutic index of tissue oxygenation in critically ill patients. Barquist E, Kirton O, Windsor J, et al: the impact of antioxidant and splanchnic-directed therapy on persistent uncorrected gastric mucosal pH in the critically injured trauma patient. Miami Trauma Clinical Trials Group: Splanchnic hypoperfusion- directed therapies in trauma: a prospective, randomized trial. Varpula M, Karlsson S, Ruokonen E, et al: Mixed venous oxygen saturation cannot be estimated by central venous oxygen saturation in septic shock. Turnaoglu S, Tugrul M, Camci E, et al: Clinical applicability of the substitution of mixed venous oxygen saturation with central venous oxygen saturation. Suehiro K, Tanaka K, Matsuura T, et al: Discrepancy between superior vena cava oxygen saturation and mixed venous oxygen saturation can predict postoperative complications in cardiac surgery patients. Vieillard-Baron A, Caille V, Charron C, et al: Actual incidence of global left ventricular hypokinesia in adult septic shock. Perner A, Haase N, Wiis J, et al: Central venous oxygen saturation for the diagnosis of low cardiac output in septic shock patients. Textoris J, Fouche L, Wiramus S, et al: High central venous oxygen saturation in the latter stages of septic shock is associated with increased mortality. Gattinoni L, Brazzi L, Pelosi P, et al: A trial of goal-oriented hemodynamic therapy in critically ill patients. Bakker J, Coffernils M, Leon M, et al: Blood lactate levels are superior to oxygen-derived variables in predicting outcome in human septic shock. Zhang Z, Xu X: Lactate clearance is a useful biomarker for the prediction of all-cause mortality in critically ill patients: a systematic review and meta-analysis. Kopterides P, Bonovas S, Mavrou I, et al: Venous oxygen saturation and lactate gradient from superior vena cava to pulmonary artery in patients with septic shock. Improvement of ultrasound technology allowed for miniaturization of equipment and reduced costs, allowing this technology to find its way into all corners of patient care. Many clinicians quickly adopted echocardiography, and the more focused form of it—focused cardiac ultrasound—as a diagnostic tool for their patients. The relative ease of use, rapid retrieval of information along with low complication rates, has all led to adaptation of echocardiography to the critical care environment. With growing experience and knowledge managing patients with this new modality, echocardiography is now used by critical care physicians not only for initial diagnosis but also as a form of monitoring. This paradigm shift challenges the traditional way of “doing business” with regard to hemodynamic monitoring. Although there is still no clear-cut evidence of its benefits, echocardiography is well received by clinicians, maybe because “seeing is believing. However, patient safety and optimal outcome depend heavily on a thorough understanding of both the strengths and limitations of the available technologies and their applications. The void of hemodynamic monitoring was quickly filled with “new” hemodynamic monitors, usually less invasive and some considered completely noninvasive. Although most of these monitors were evaluated by both experimental and clinical studies, to-date, no specific monitoring device has been found to reduce mortality for critically ill patients [9]. Rather, outcomes can only improve if the following three conditions are met: (1) the technique provides accurate data; (2) the data obtained is relevant to patient management; and (3) significant management changes are made based on the data obtained [10]. It is also important that the data is interpreted and applied correctly and that the applied therapies are not ineffective or harmful [10]. One major advantage echocardiography has over many other hemodynamic monitors is that it provides crucial diagnostic information during the vital moments of the first patient encounter and at the time of hemodynamic instability.

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Very ing is typically limited to determination of rhesus (D) rare deaths have been reported due primarily to antigen status order 100 mg mebendazole with visa hiv infection uganda. Testing for haemoglobin is implementation of a routine 7‐day course of doxycycline performed when there is a concern for anaemia and purchase mebendazole 100mg overnight delivery hiv transmission facts statistics, and a switch from the vaginal to buccal route of misopros- often mebendazole 100 mg sale hiv infection trends, if significant blood loss is anticipated 100 mg mebendazole with amex hiv infection and stds, although tol [21]. This is facilitated by discussing contraception up and partner notification and treatment. Screening for during the abortion assessment and providing a method infections such as syphilis, hepatitis B and hepatitis C may at the time of treatment. Initiation of any hormonal occur on a selective basis, influenced by sexual health risk method including the contraceptive implant, or insertion assessment and population disease prevalence. For all tests it is important to may be increased slightly with immediate insertion after ensure that the result can be communicated to the woman second‐trimester surgical abortion but is far lower than and appropriate action taken on any abnormal result. Similarly, women may start any hormonal contra- ceptive method at the time of a medical abortion. Condoms (male and female) can focused on establishing gestational age, eligibility for be used at any time after abortion and women may be a choice of treatment options and location of care, and offered emergency contraception (levonorgestrel or uli- the need for anti‐D prophylaxis. Provision of and pain management options are available to her; what information, along with decision‐making support if will be done before, during and after the procedure includ- needed, are essential to helping a woman select an abor- ing any tests or examinations; what she is likely to experi- tion method that is right for her and which will optimize ence (e. In both the first and second tri- where the procedure will occur; and how long the process mesters, presuming no contraindications, abortion may is likely to take, including the need for any follow‐up. Both methods can be mester should be advised of the variable duration of the used in the case of multiple gestations. Surgical fer surgical abortion because it is predictable and quick, abortion in the second trimester may require cervical can be performed with a general or local anaesthetic or preparation up to 24 hours before the evacuation so sedation, and has a low risk of complications. Others pre- women need to be prepared for a procedure over 2 days fer medical abortion because it does not involve surgical although admission is not required. In addition, medical abortion at address are whether her partner or another support per- a gestation of 70 days or less may be managed safely and son may be present during treatment and whether she effectively by the woman in the privacy of her own home may see the fetus or need to dispose of the products of which is preferred by many to care in a clinical setting. The World Health Organization’s been challenging to undertake because many women Clinical Practice Handbook for Safe Abortion (www. In the few studies available, some of which comparing the characteristics of various methods. Services with appropriately the gestational age limit at which abortion is offered. Surgical abortion in the first trimester For these women, it is not acceptable to defer the abor- tion and their preference might not be for medical abor- Vacuum aspiration is the recommended method of sur- tion; indeed there could be contraindications to medical gical abortion in the first trimester. Protocols which incorporate routine inspec- tion and sharp curettage (D&C), vacuum aspiration is tion of the uterine aspirate for the gestational sac, ultra- faster and associated with less pain and blood loss. Vacuum aspiration may be performed with an electric Cervical priming agents are often used before vac- suction machine or a manual vacuum aspirator which uum aspiration to reduce or eliminate the need for employs one or two valves and a locking plunger in a mechanical dilatation. Safety, effectiveness such as the progesterone antagonist mifepristone and and acceptability of electric and manual aspiration are the prostaglandin analogue misoprostol, and osmotic equivalent [26]. Priming agents sof- used, the diameter chosen typically being the same in ten the cervix and open the os, leading to a slightly millimetres as the weeks of gestation. One trial demonstrated a mon, however, for manual vacuum aspiration to be decreased need for uterine re‐evacuation for incom- performed with sequential use of 4‐, 5‐ and 6‐mm can- plete abortion among women who received misopros- nulae, avoiding the need to mechanically expand the cer- tol for cervical preparation as compared to a placebo vical os with rigid tapered metal or plastic dilators. Only osmotic dilators have been single valve manual vacuum aspirator can accommodate shown to reduce the risk of cervical laceration and uter- cannulae up to 6mm in diameter and the double value ine perforation; studies of pharmacological agents have with cannulae up to 12 mm in diameter. With larger‐bore not been sufficiently powered to determine whether tubing and cannulae available up to 16 mm, electric vac- they too lead to a reduction in these rare but serious uum aspiration can be used into the second trimester complications. Historically, vacuum aspiration has been avoided A dose of 400µg is effective when administered per under 7 weeks’ gestation based on a cohort study that vagina 3 hours before the evacuation or sublingually 1 or found a higher rate of missed abortion at gestations 2 hours before surgery [33]. Side effects include nausea, below 7 weeks’ compared with 7–12 weeks’ gestation vomiting, diarrhoea, chills, cramping and bleeding. Mifepristone is better tolerated and achieves greater baseline cervical dilation than mis- oprostol, but requires administration at least 24 hours preoperatively and is significantly more expensive. Given the side‐effect profile of misoprostol and limited evidence of risk reduction, many providers base its use on risk factors for cervical or uterine injury. Common indications are age 17 years or less, prior cervical sur- gery, and gestational age over 12 weeks. Pain management options for vacuum aspiration include local cervical anaesthesia with oral analgesia, conscious sedation, and general anaesthesia. Reproduced with permission of remains a lack of consensus on the ideal cervical anaes- Womancare Global. At this stage, the woman may feel a strong Advantages of local anaesthesia include faster recov- cramp. Calm and comforting conversation to distract the ery, a greater sense of control for the woman, and a woman and explaining the meaning of unpleasant sensa- reduction in procedural risks such as haemorrhage and tions will help her tolerate the procedure. The vulsellum or tenaculum is not eliminate discomfort and some women may find removed and the cervix inspected for bleeding. For women who want greater of low rates of haemorrhage, oxytocics are not routinely pain and anxiety management than local anaesthesia administered. The operator should ascertain that the provides but do not want to be asleep, low‐dose intrave- gestational sac and any fetal parts, consistent with the nous fentanyl and midazolam can be provided to achieve gestational age, have been removed. Women’s preference, risk sound guidance is increasingly used but is not required if factors for anaesthetic complications, setting and the aspirate will be inspected. Once the operator is cer- resources should be considered when choosing a method tain of completion, the woman should be reassured. Vacuum aspiration is a straightforward procedure but careful practice is important so that pregnancies are Surgical abortion in the second trimester evacuated completely and safely. Asepsis cannot be maintained during an abortion because contamination Electric vacuum aspiration can be performed up to 16 of gloved hands occurs once the woman is touched. Careful and preparation and removal of the fetus and placenta with gentle instrumentation avoids injury to the cervix or specialized forceps, D&E is associated with a low risk of uterus and good communication is needed between the complications and is highly acceptable to women. When operator, the woman and other members of the surgical second‐trimester surgical abortion was compared in a team. Precise techniques vary among providers and with randomized trial with medical abortion, significantly anaesthetic regimens. This section describes electric fewer women found the surgical option worse than vacuum aspiration with local anaesthesia. After confirming the position, size and extraction (D&X), is performed after very wide (median shape of the uterus by bimanual examination, a bivalve 5cm) cervical dilation is achieved using osmotic dilators speculum is placed in the vagina. This is followed by an assisted are cleansed with an antiseptic solution such as chlo- partial breech delivery, decompression of the calvarium, rhexidine. Local anaesthetic is administered by first and delivery of the fetus otherwise intact. Hysterotomy injecting 1–2mL 1% buffered lidocaine at the 12 o’clock and hysterectomy are outdated methods and only used position on the cervical face. Obstruction is applied and, with gentle outward traction, an addi- by a large, distorting cervical or uterine tumour is an tional 18 mL of buffered lidocaine is injected in equal ali- example of when these methods might be employed. Adequate cervical preparation is essential for safe Cervical dilation to the diameter of the suction cannula D&E provision. The amount of cervical expansion is performed with tapered metal or plastic dilators (e.

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If right axillary artery cannulation has been used purchase 100 mg mebendazole with amex antiviral iv medication, the tube graft can be filled by removing the clamp on the innominate artery cheap 100mg mebendazole fast delivery stages of hiv infection according to who. After cardiopulmonary bypass is reestablished cheap mebendazole 100mg with mastercard who hiv infection stages, additional doses of blood cardioplegic solution are administered by the retrograde technique and antegrade into the P best mebendazole 100mg hiv infection experiences. When the aorta is otherwise normal and there is no aortic valve insufficiency, the proximal aorta that has been transected at approximately 1 cm above the level of aortic commissures is reinforced with glue and a single or double layer of Teflon felt, as described for the distal anastomosis. The tube graft is tailored to an appropriate length and anastomosed to the proximal aorta with 4-0 Prolene continuous suture. Often, however, there may be associated aortic insufficiency due to aortic root dissection or dilation. When the valve leaflets are not diseased and the remainder of the aortic root is normal, every attempt is made to retain the aortic valve. Any incompetent commissure is resuspended by curing the dissected root with BioGlue and reinforced with an external felt strip. Usually, a single pledgeted Prolene suture is placed immediately above each of the commissures and tied down in order to resuspend the commissural posts further. This tailored proximal anastomosis reestablishes a new sinotubular junction, incorporating the resuspended commissures to ensure a competent aortic valve. Aortic root replacement as originally described by Bentall consisted of replacement of the aortic valve and the ascending aorta including the aortic root, and reimplantation of the coronary arteries into the tube graft all within the native aorta. There appears to be an increased incidence of pseudoaneurysm formation, probably because of insecure hemostasis at the anastomotic suture lines masked by the wrapping of the aorta. With the introduction of improved tube grafts and aortic root conduits as well as better surgical techniques for anastomosis and hemostasis, simple interposition of a valve conduit is now the method of choice. The Interposition Technique the aorta is divided approximately 15 mm above the commissures, followed by excision of all the diseased aortic wall up to the lesser curvature of the aortic arch. Subsequently, they are passed through the lower portion of the sewing ring of the composite valve graft, leaving 2 to 3 mm of the upper sewing cuff free. The prosthesis is lowered into position, and the sutures are tied, taking all the precautions as in aortic valve replacement (see Chapter 5). This remaining aortic wall with its adventitial tissue is now brought forward and sewn to the upper portion of the sewing ring of the prosthesis with a continuous 3-0 Prolene suture. The suture should go through in the order of adventitia, annulus, sewing ring, and then back outside of the folded adventitia. Circular holes are made in the tube graft with an ophthalmologic cautery device for reimplantation of the coronary artery buttons. The coronary artery buttons are now attached to these openings with continuous 5-0 Prolene sutures. It is often advisable to delay reimplantation of the right coronary button until the distal aortic anastomosis is completed. The cross-clamp is briefly removed, and the heart is allowed to fill so that the correct site for reimplantation of the right coronary can be marked. Bleeding from the Coronary Artery Suture Line Implantation of the coronary artery buttons on the graft must be performed meticulously. Control of bleeding from these sites, particularly the left coronary artery anastomosis, at a subsequent stage is challenging. If a tube graft is already attached to the distal aorta, the proximal and distal tube grafts are now tailor cut and anastomosed to each other with a continuous 3-0 or 4-0 Prolene suture. Use of the composite valvular conduit should be preferred to isolated aortic valve replacement followed by tube graft replacement of the aorta above the sinotubular junction. This latter technique may leave behind diseased sinuses of Valsalva and put the patient at risk of later development of aortic sinus aneurysms. Inability to Directly Connect the Coronary Arteries to the Tube Graft Composite valvular tube graft replacement entails reimplantation of the coronary arteries into the graft. Use of saphenous vein grafts to bypass the major branches of the coronary arteries can be an alternate technique and is implemented whenever direct coronary artery to graft continuity cannot be safely accomplished. An alternative technique uses a short segment (less than 1 cm in length) of an 8-mm Hemashield tube graft interposed between the coronary ostia and the aortic graft. This has been found to be useful in some patients in whom the coronary buttons are difficult to mobilize. Coronary Artery Implantation A kink or twist of the coronary arteries at the implantation site interferes with normal coronary perfusion and can give rise to myocardial ischemia. The surgeon must be aware of this possibility during anastomosis of the coronary ostia to the graft to prevent misalignment. Stenosis of the Coronary Artery Ostia To minimize the possibility of ostial stenosis, the anastomosis should incorporate a wide margin of the aortic wall around each coronary ostium. Saphenous Vein Bypass Grafts When the patient has associated coronary artery disease, it may be necessary to use saphenous vein grafts or appropriate arterial grafts to bypass the occluded branches of the coronary arteries concomitantly with the aortic surgery. As the patient is rewarmed and all suture lines are secured, deairing is carried out and the patient is gradually weaned from cardiopulmonary bypass. Aortic root venting is performed with an air vent needle through the graft before removing the clamp across the tube graft. The clamp is then reapplied partially across the anterior portion of the graft distal to the needle vent (see Venting and Deairing of the Heart section in Chapter 4). Air Removal the vent needle for air removal should not be inserted in the aorta distal to the graft to avoid starting a new site of dissection. Techniques for Aortic Root Replacement with a Bioprosthesis When a tissue valve is preferred during concomitant valve and root replacement, a stented porcine or bovine pericardial valve is sewn inside a Hemashield tube graft. The valve is placed inside the tube graft, which is sewn to the top of the sewing ring using a running 4-0 Prolene suture. It is important to mark the tube graft at 0, 120, and 240 degrees, where the struts of the bioprosthesis will be aligned. After tying down two knots, one arm of one suture is sewn along one half of the sewing ring while the other arm secures the other side. This handmade composite valve graft conduit is then implanted as described for the mechanical composite valve graft. A series of simple interrupted 4-0 Ticron sutures are placed closely in a planar manner at the level of the annulus and below the commissures. The coronary stumps of the bioprosthesis are removed and the coronary buttons are reimplanted into their respective openings using 5-0 Prolene sutures. The Freestyle bioprosthesis can usually be oriented in its anatomic position without tension on the coronary button anastomoses. In fact, the outpouching nature of bioprosthetic coronary stumps reduces the need for extensive mobilization of the coronary artery buttons. However, when the native coronary buttons are more than 120 degrees apart as in a congenitally bicuspid valve, the stentless valve should be rotated 120 degrees. For reattachment of the coronary artery buttons, only one of the coronary stumps is removed and a second opening is made in the noncoronary sinus of the bioprosthesis using a 4-mm aortic punch. Aortic Valve-Sparing Root Replacement Patients with aortic root disease, such as those with Marfan syndrome, have progressive dilation of the aortic sinuses and aortic annulus, which can lead to aortic valve insufficiency despite normal aortic valve leaflets. In these patients, it is possible to replace the diseased aortic root and preserve the aortic valve by reimplanting it inside a Dacron tube graft. All three sinuses of Valsalva are excised, leaving approximately 5 mm of arterial wall attached to the aortic annulus.

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