Annette Vegas

Quantification of Mitral Valve Anatomy by Three-Dimensional Transesophageal Echocardiography in Mitral Valve Prolapse Predicts Surgical Anatomy and the Complexity of Mitral Valve Repair

BACKGROUND Three-dimensional (3D) transesophageal echocardiography (TEE) is more accurate than two-dimensional (2D) TEE in the qualitative assessment of mitral valve (MV) prolapse (MVP). However, the accuracy of 3D TEE in quantifying MV anatomy is less well studied, and its clinical relevance for MV repair is unknown. METHODS The number of prolapsed segments, leaflet heights, and annular dimensions were assessed using 2D and 3D TEE and compared with surgical measurements in 50 patients (mean age, 61 ± 11 years) who underwent MV repair for mainly advanced MVP. RESULTS Three-dimensional TEE was more accurate (92%-100%) than 2D TEE (80%-96%) in identifying prolapsed segments. Three-dimensional TEE and intraoperative measurements of leaflet height did not differ significantly, while 2D TEE significantly overestimated the height of the posterior segment P1 and the anterior segment A2. Three-dimensional TEE quantitative MV measurements were related to surgical technique: patients with more complex MVP (one vs two to four vs five or more prolapsed segments) showed progressive enlargement of annular anteroposterior (31 ± 5 vs 34 ± 4 vs 37 ± 6 mm, respectively, P = .02) and commissural diameters (40 ± 6 vs 44 ± 5 vs 50 ± 10 mm, respectively, P = .04) and needed increasingly complex MV repair with larger annuloplasty bands (60 ± 13 vs 67 ± 9 vs 72 ± 10 mm, P = .02) and more neochordae (7 ± 3 vs 12 ± 5 vs 26 ± 6, P < .01). CONCLUSIONS Measurements of MV anatomy on 3D TEE are accurate compared with surgical measurements. Quantitative MV characteristics, as assessed by 3D TEE, determined the complexity of MV repair.

Bivalirudin anticoagulation for cardiopulmonary bypass in a patient with heparin-induced thrombocytopenia.

PurposeTo describe the perioperative management in a heparin-induced thrombocytopenia (HIT) positive patient who had prosthetic valve endocarditis and an aortic root abscess. The patient underwent high-risk cardiac re-operation with the use of the alternative anticoagulant, bivalirudin.Clinical featuresA 62-yr-old patient who underwent stentless tissue aortic valve replacement with a Toronto-SPV valve in 1998, was admitted to hospital with symptoms of stroke. A heparin infusion was started and further investigation revealed positive blood cultures. The patient developed HIT which was confirmed by laboratory tests. Echocardiographic examination performed one month later showed vegetations on the aortic tissue valve and a small aortic root abscess. The patient still tested positively for the presence of HIT antibodies and was treated conservatively with antibiotics. A repeat echocardiographic examination showed progression of the aortic root abscess and it was decided to proceed with urgent redo aortic valve surgery. Anticoagulation for cardiopulmonary bypass (CPB) was achieved with the use of a direct thrombin inhibitor (DTI), bivalirudin. Following an uneventful wean from CPB, hemostasis was achieved within 40 min. The postoperative course was uncomplicated and the patient was discharged from hospital on the seventh postoperative day.ConclusionBivalirudin is a DTI, which can be used as an alternative anticoagulant for CPB in HIT positive patients. This case report showed a favourable outcome with bivalirudin for urgent complex redo cardiac surgery requiring CPB.RésuméObjectifDécrire la prise en charge périopératoire ďun patient atteint de TIH, victime ďune endocardite sur prothèse valvulaire et ďun abcès à la racine de ľaorte. Le patient a subi une réopération cardiaque à haut risque avec ľusage ďanticoagulant de remplacement, la bivalirudine.Éléments cliniquesUn patient de 62 ans chez qui on a remplacé le tissu de la valve aortique, sans endoprothèse, par une valve Toronto-SPV en 1998 a été admis à ľhôpital pour des symptômes ďaccident vasculaire cérébral. Une perfusion ďhéparine a été amorcée et un examen ultérieur a révélé des cultures sanguines positives. Une TIH s’est développée et a été confirmée par les tests de laboratoire. Ľéchocardiographie, réalisée un mois plus tard, a montré des végétations sur la valve tissulaire aortique et un petit abcès à la racine de ľaorte. Les résultats aux tests indiquant toujours la présence ďanticorps de TIH, le patient a reçu une antibiothérapie conservatrice. Une nouvelle échocardiographie a montré la progression de ľabcès aortique, ce qui a conduit à répéter ďurgence ľopération de la valve aortique. Ľanticoagulation pour la circulation extracorporelle (CEC) a été réalisée avec un inhibiteur direct de la thrombine (IDT), la bivalirudine. Après un sevrage sans incident de la CEC, ľhémostase a été atteinte en moins de 40 min. Aucune complication n’est survenue par la suite et le patient a quitté ľhôpital au septième jour postopératoire.ConclusionLa bivalirudine est un IDT qui peut être utilisé comme anticoagulant de remplacement pendant la CEC chez des patients victimes de TIH.

Assessment of mitral valve prolapse by 3D TEE angled views are key.

ASSESSMENT OF MITRAL VALVE ANATOMY by real-time 3-dimensional (3D) transesophageal echocardiography (TEE) has proven to be superior compared to 2-dimensional TEE ([1,2][1]). The standard modalities of real-time 3D TEE have recently been described ([3][2]). Demonstration of the mitral valve as seen

A bedside clinical and ultrasound-based approach to hemodynamic instability - Part II: bedside ultrasound in hemodynamic shock: Continuing Professional Development

Shock is defined as a situation where oxygen transport and delivery is inadequate to meet oxygen demand. The patient in shock is evaluated through medical history, physical examination, and careful observation of the hemodynamic and respiratory monitors. The patient is initially managed with basic resuscitation measures, however bedside ultrasound should be performed if hemodynamic instability persists. We propose to use ultrasound of the inferior vena cava (IVC), and the concept of venous return, as the initial step in order to identify the mechanism of shock. Doppler examination of the hepatic venous flow can also be added. Further ultrasound examination of the patient’s heart, thorax, and abdomen can then be performed in order to determine the etiology of shock. In patients with reduced mean systemic venous pressure, an examination of the patient’s thoracic and abdominal cavities to detect free fluid, pneumonia, or empyema can be considered. In patients with increased right atrial pressure, transthoracic echocardiography will allow identification of left or right ventricular dysfunction. Finally, in the presence of increased resistance to venous return, thoracic examination for pneumothorax or cardiac tamponade and abdominal examination for signs of abdominal compartment syndrome or IVC occlusion can be considered. Subsequent treatment can then be tailored to the etiology of shock. Elements of bedside ultrasound examination are currently taught in many anesthesia training programs.PurposeTo develop an approach to the patient in shock that incorporates bedside ultrasound examination.RésuméOn définit le choc comme une situation dans laquelle le transport d’oxygène est incapable de répondre à la demande en oxygène. On évalue le patient en état de choc en fonction de ses antécédents médicaux, de l’examen physique, ainsi que de l’observation minutieuse des moniteurs hémodynamiques et respiratoires. Le patient est d’abord pris en charge à l’aide de mesures de réanimation de base; toutefois, si l’instabilité hémodynamique persiste, il convient de réaliser une échographie au chevet. Nous proposons d’utiliser une échographie de la veine cave inférieure (VCI) dans le cadre du concept du retour veineux, comme première étape dans l’identification du mécanisme du choc. L’examen Doppler des veines hépatiques peut également être ajouté. Un examen échographique plus approfondi du cœur, du thorax et de l’abdomen du patient peut être réalisé par la suite afin de déterminer l’étiologie du choc. Chez les patients dont la pression veineuse systémique est réduite, on peut envisager un examen des cavités thoracique et abdominale afin de détecter du liquide libre, une pneumonie ou un empyème. Chez les patients dont la pression auriculaire droite est accrue, une échocardiographie transthoracique permettra d’identifier le mécanisme du dysfonctionnement ventriculaire gauche ou droit. Enfin, si le retour veineux rencontre une résistance accrue, on peut envisager de réaliser un examen thoracique afin d’exclure la présence de pneumothorax ou de tamponnade cardiaque et un examen abdominal pour détecter les signes d’un syndrome du compartiment abdominal ou d’une occlusion de la VCI. Le traitement subséquent peut alors être personnalisé en fonction de l’étiologie du choc. Des éléments de l’examen échographique au chevet sont actuellement enseignés dans de nombreux programmes de formation en anesthésiologie.ObjectifMettre au point une approche du patient en état de choc qui incorpore l’examen échographique au chevet.

The successful management of severe protamine-induced pulmonary hypertension using inhaled prostacyclin.

Acute pulmonary hypertension is a severe and life-threatening reaction that rarely occurs secondary to protamine administration. Management of systemic hypotension combined with severe pulmonary hypertension causing right ventricular failure is challenging. We describe a case of acute pulmonary hypertension induced by protamine during elective coronary artery bypass surgery refractory to multiple systemic inotropic and vasopressor therapies. After inhaled prostacyclin administration, our patients pulmonary artery pressures decreased from 70/37 to 45/23 mm Hg within 10 min. The case highlights a role for inhaled nebulized prostacyclin as a selective pulmonary vasodilator with minimal systemic hypotensive effects.

Ascending aortic aneurysms in unicommissural aortic valve disease

BACKGROUND Aneurysms of the ascending aorta occur as result of intrinsic changes in the aortic wall and have been well documented in patients with bicuspid aortic valve (BAV). In few reported clinical studies, documenting aneurysmal dilatation in unicommissural aortic valves (UAV); there have been no comments on the aortic wall pathology. This study presents the pathological findings of the ascending aorta in patients with UAV. MATERIALS AND METHODS The clinical data from 39 patients with concomitant excision of the UAV and aneurysmal aortic tissue were reviewed. In all cases, the gross features of the valve and aortic segments were noted and submitted for histology. The sections of the aorta were semi-quantitatively graded for the extent of medionecrosis, cystic medial change, fibrosis, and elastic tissue changes (fragmentation/ loss) in the media. The medial alterations were correlated with patient age, gender, and valvular dysfunction, and compared to aneurysmal disease in BAV and three-cuspid aortic valves (TAV) excised over a 3-year period. RESULTS Among 39 patients studied, a majority were males (92.3%), with a mean age at surgery of 39.92 years. Only three patients (7.69%) were above the age of 50 years. Eighteen patients (46.1%) had aortic stenosis with regurgitation. Ascending aorta diameters ranged from 4 to 5.5 cm. The overall pattern of medial changes was nearly the same in all cases of UAV, irrespective of age and nature of valvular dysfunction. Most cases showed mild histological changes, with medionecrosis and fibrosis being the more common and consistent features. However, varying grades of change affected different portions of the media and/or the aortic wall in the same patient. The changes in UAV aortae were comparable to the changes seen in the TAV and BAV, but these differed with the age of onset. CONCLUSIONS This study demonstrates the presence of medial changes in the ascending aortic tissue in all patients of UAV with aneurysms. These changes, while mild to moderate in degree, likely have a similar pathogenetic mechanism as those seen in BAV disease. The significant difference in age, at the time of surgery, suggests a more rapid progression of the aortic changes.

Mitral Regurgitation Due to Myxomatous Degeneration Combined With Bicuspid Aortic Valve Disease is Often Due to Prolapse of the Anterior Leaflet of the Mitral Valve

BACKGROUND This study examines the clinical, echocardiographic, surgical, and pathologic features of patients who had heart valve operations for combined congenital bicuspid aortic valve and mitral regurgitation due to degenerative disease of the mitral valve. METHODS A retrospective review of 1595 patients who had procedures for mitral regurgitation due to degenerative disease of the mitral valve and 1820 patients who had procedures for congenital bicuspid aortic valve disclosed 29 patients who had combined diseases. RESULTS The most common morphology of the bicuspid aortic valve was type 1 (fused right and left aortic cusps). Mitral regurgitation in 21 of 29 patients was caused by prolapse of the anterior leaflet, which was exceptionally large (mean height, 36.5 +/- 6.6 mm). Patients with prolapsed anterior leaflet of the mitral valve were younger (48 +/- 13 years vs 58 +/- 16 years, p = 0.01) and 95% were men. The bicuspid aortic valve was incompetent in 19 of 21, and the aortic annulus exceeded 30 mm in 20 of 21 patients. CONCLUSIONS Patients with combined mitral regurgitation due to myxomatous degeneration and bicuspid aortic valve disease who require operations often have a large, prolapsing anterior leaflet of the mitral valve and dilated aortic annulus with aortic insufficiency due to cusp prolapse.

Bedside clinical and ultrasound-based approaches to the management of hemodynamic instability - Part I: focus on the clinical approach: Continuing Professional Development

Shock is defined as a situation where oxygen transport is inadequate to meet the body’s oxygen demand. An understanding of the mechanism(s) of reduced cardiac output, a determinant of oxygen transport, is crucial in order to initiate appropriate therapy to manage shock. Combining the concept of venous return with the ventricular pressure-volume relationship is a useful method to appreciate the complex circulatory physiology of shock. Clues from the patient’s history, physical examination, and key laboratory tests, along with the careful inspection of hemodynamic, electrocardiographic and respiratory waveforms can help with the identification of the etiology and mechanism(s) of shock. Following verification of the arterial pressure, general resuscitation can begin, and more specific treatment can be undertaken to manage shock. If the patient is unresponsive to these measures, bedside ultrasound can then be performed to ascertain more detail regarding the mechanism(s) and etiology of shock.PurposeTo develop an approach to the management of the hemodynamically unstable patient.Principal findingNot applicable.ConclusionNot applicable.RésuméLe choc est défini comme étant une situation où le transport de l’oxygène est insuffisant pour répondre aux besoins en oxygène de l’organisme. La compréhension des mécanismes entraînant la baisse du débit cardiaque, un déterminant du transport de l’oxygène, est essentielle pour initier une thérapie adaptée à la gestion du choc. La combinaison du concept de retour veineux avec le rapport pression-volume ventriculaire est une méthode utile pour apprécier la physiologie circulatoire complexe au cours du choc. Des indices fournis par les antécédents du patient, l’examen physique et des tests de laboratoire essentiels, ainsi que par l’inspection soigneuse des tracés hémodynamiques, électrocardiographiques et respiratoires, peuvent aider à identifier l’étiologie et le ou les mécanismes du choc. Une réanimation générale peut commencer après avoir vérifié la pression artérielle à plus d’un site, puis un traitement plus spécifique peut être entrepris pour gérer le choc. Si le patient ne répond pas à ces mesures, un examen échographique peut alors être réalisé pour déterminer plus précisément le ou les mécanismes et l’étiologie du choc.ObjectifDévelopper une méthode d’approche pour la gestion d’un patient hémodynamiquement instable.

Assisting the Failing Heart

Anesthesiologists increasingly encounter patients who have a spectrum of heart failure ranging from stable chronic heart failure to acute heart failure to cardiogenic shock. Improved medical therapy has increased the survival of patients who have chronic heart failure but not of patients who have acute heart failure. New surgical techniques and mechanical devices may offer alternatives to certain patients who have refractory heart failure This article provides an overview of established and newer pharmacologic and nonpharmacologic therapies and surgical interventions to manage patients who have heart failure, including the perioperative management of heart transplantation and ventricular assist devices.

Three-dimensional transesophageal echocardiography: Principles and clinical applications

A basic understanding of evolving 3D technology enables the echocardiographer to master the new skills necessary to acquire, manipulate, and interpret 3D datasets. Single button activation of specific 3D imaging modes for both TEE and transthoracic echocardiography (TTE) matrix array probes include (a) live, (b) zoom, (c) full volume (FV), and (d) color Doppler FV. Evaluation of regional LV wall motion by RT 3D TEE is based on a change in LV chamber subvolume over time from altered segmental myocardial contractility. Unlike standard 2D TEE, there is no direct measurement of myocardial thickening or displacement of individual segments.