Three Investigators Ebook' title='Three Investigators Ebook' />Quantification of mitral regurgitation. With echocardiography it is easy to detect mitral regurgitation. In contrast, quantification of mitral regurgitation is much more difficult. It calls for considerable experience. No single method or feature can be used to fully describe the severity of mitral regurgitation. All components of quantification must be considered an integral approach should be adopted. In addition, it is important to understand the hemodynamics and sequelae of mitral regurgitation. Put all the pieces of the puzzle together and interpret your findings in the context of clinical findings. Ultimately, the severity of mitral regurgitation determines whether one opts for a surgical, an interventional e. Mitra. Clip procedure or a conservative approach. Qualitative visual assessmentSemiquantitative. Quantitative. Jet size vena contracta, flow convergenceSize of vena contracta. PISA method. LV size and function, LV volume overload Size of flow convergence zone. A summary of Part Three Benito Jurez Infirmary, Tomatln, Mexico Chapters 96100 in Yann Martels Life of Pi. Learn exactly what happened in this chapter. Nutritionist Brooke Alpert and dermatologist Dr Patricia Farris say they can help sugar addicts kick the habit in just three days. Womans Life In Colonial Days Scholars Choice Edition Summary Womans life in colonial days scholars choice edition summary womans life in colonial days scholars. Volumetric method. PA pressure. Jet areaMV morphologyleft atrial sizeother indirect signs1. The mitral regurgitation jet. Im sorry, theres no heartbeat, my doctor said to me. She didnt sound very sorry, leaving the room so quicklyostensibly so I could pull up my. Three Investigators Ebook' title='Three Investigators Ebook' />Color Doppler is able to directly display the high velocity backflow of blood into the left atrium in form of a jet. The dominant color of the jet corresponds to the direction of flow red to, and blue away from, the transducer. As velocities in such jets exceed the Nyquist limit and because of turbulent flow see Chapter 1 Principles of echocardiography, there will also be an array of other colors in the jet. It is this aliased flow that makes jets easily visible. In general, the larger the jets are, the more regurgitation is present. How does one quantify the size of a jet What factors, aside from the degree of regurgitation, influence the way a jet is displayed To answer these questions we first have to look at the various components of a jet Components of a jet. MR jet impinging on the interatrial septum. Note the proximal flow convergence zone. Vena contracta. Mitral regurgitation is a dynamic process the magnitude of regurgitation differs in early, mid, and late systole. Flow convergence zone The flow convergence zone is the zone of increased flow velocity before the regurgitant orifice, just as the flow of water in a river increases prior to a rapid. Another analogy would be the swirls of water one sees in a bathtub close to the outlet. The velocity of flow increases towards the regurgitant orifice in concentric shells, causing a more or less semicircular region of aliased flow. The size of this region corresponds to the magnitude of blood flow and the size of the regurgitant orifice. Thus, it can be used to quantify the severity of regurgitation. The flow convergence zone is probably the most important part of the jet when it comes to quantifying regurgitation. Visual assessment of the severity of mitral regurgitation is based on the flow convergence zone. It may also be used to directly measure the volume of regurgitation and the effective regurgitant orifice area with the aid of the PISA method see below. It is quite difficult to quantify the size of the flow convergence zone. Quantification methods solely based on actual measurements have several limitations these will be discussed in the section on the PISA method. However, one may use a crude semiquantitative scale Trivial or mild forms of regurgitation are characterized by the absence of a flow convergence zone too small to be detected with echo. In moderate forms the flow convergence zone will be visible but small Vena contracta The vena contracta corresponds to the region in which blood passes through the valve. Velocity is highest here. The width of the vena contracta is a good marker of the severity of mitral regurgitation because it corresponds to the diameter of the regurgitant orifice area. A diameter exceeding 7 mm indicates severe regurgitation. However, like all distance measurements it is limited by two facts a regurgitant orifices may have many geometric shapes, b quite often more than one jet is present. Nevertheless, the vena contracta is an important clue to the severity of regurgitation. Jet body The portion of the jet that is seen in the receiving camber the left atrium is the jet body. Its size also corresponds to the severity of mitral regurgitation. Several methods of quantification have been proposed, including jet area and jet length. However, none of these parameters are reliable because they are strongly dependent on color gain and color aliasing settings. Specifically, the length of the jet and whether or not it reaches the roof of the left atrium are no good markers of severity. Other proposed methods, such as jet area or the relationship between jet area and the left atrium are more accurate. Yet, none of these parameters can be used alone to quantify regurgitation. These methods lead to underestimation of severity in eccentric jets because they are prone to the Coanda effect, in which the jet impinges the left atrial wall. A part of the jet energy is lost and the jet appears to be smaller. Beware of optical illusions Relate the size of the jet to the size of the left atrium. In large atria the jet may appear smaller than it is. The severity of mitral regurgitation is also influenced by the driving pressure of the left ventricle. Hypertension, for instance, may increase the degree of regurgitation. Poor imaging of the jet is the greatest source of error in quantifying regurgitation. Quantification based on color Doppler. Mild. Moderate. Severe. Vena contracta mmlt 3. Jet area Small central jet lt 2. LA areaVariable. Large central jet gt 4. LA areaIn summary, the jet and its components permit a qualitative as well as semiquantitative approach to quantification. Regurgitation is usually graded as trivialmild, moderate or severe. Although this approach is quite subjective and has several limitations, it works well and still is the most widely used method. In fact, there is widespread agreement among experienced investigators in this regard. The following examples provide templates for quantification. Trace MRMild MRSevere MR1. Imaging of the jet. Every jet looks different. Its origin, direction and magnitude may vary considerably. Besides, more than one jet may be present. Thus, all segments of the valve must be visualized when imaging regurgitation. Use a sweep technique to search for jets, and display their full extent with atypical views as well. Optimize the 2. D image before you use color Doppler because poor image quality in 2. D will lead to poor Doppler quality. The way a jet is displayed also depends on the angle of insonation. Centrally directed jets will not be adequately displayed from a parasternal long axis view. Therefore, use a transducer position that is as parallel as possible to the jet. Several orthogonal views will be needed to appreciate the shape and three dimensionality of a jet. For this purpose, rotate the transducer around the axis of the jet. Imaging should be tailored to the jet not to standard views. As mentioned earlier, imaging should focus on proximal portions of the jet, the flow convergence zone, and the vena contracta. In certain settings e. This may also lead to overestimation of its severity. To display the timing of regurgitation use CW Doppler through the jetMid to late systolic jet the spectrum starts long after the QRS complex. Finally, machine setting plays an important role. Spark. Notes Life of Pi Part Three Benito Jurez Infirmary, Tomatln, Mexico Chapters 9. Summary. Two officials from the Maritime Department in the Japanese. Ministry of Transport, Tomohiro Okamoto and Atsuro Chiba, are in. California on unrelated business when they hear that Pi has made landfall. Tomatln, Mexico. The Ministry directs them to speak with Pi. Japanese Tsimtsum, to. Okamoto looks at a map. Tomatn, in Baja California, with Tomatln. Mexico. He decides to drive to see Pi, but the journey is full. By the time Okamoto and Chiba reach Pi, they are exhausted. They set about interviewing Pi, in English. Martel provides us with. Okamoto and Chiba in Japanese and which Martel has had translated. The translated passages are presented to the reader. The interview begins. It is February 1. Chiba has turned on the tape recorder, so the entire conversation. Okamoto introduces himself and Chiba, his assistant. Chiba is new at his job, and Okamoto tells him to pay attention. Pi asks the two men if they had a nice trip coming. California, and Okamoto says that they had a wonderful. Pi says he had a horrible trip. Prior to meeting Pi, Okamoto. Chiba saw the lifeboat. Now they offer Pi a cookie, which he. Chapter 9. 7 consists. The story. Okamoto and Chiba tell Pi that they. Japanese they express their. Pi asks for another cookiehe has taken to storing cookies. Okamoto decides to take a break and tells. Pi they will be right back. When the two men return, they tell Pi that they do not. For example, they say, bananas do not float. Pi pulls two bananas out from under his bed sheet and asks the men. Okamoto fills the sink and tests. Okamoto continues grilling Pi, telling. Chiba pipes up and says that his uncle is a. Pi cleverly states that bonsai treesThree hundred year old. Okamoto says. there has been no trace of Richard Parker in or around Tomatln. Pi explains that wild creatures are adept at hiding from humans. Pi asks the two men if they disliked his story. Okamoto. replies that they enjoyed it, but that they need to know what really. Pi says he will tell another story. In this story, the. Carmax Or Drivers World. Pi, his mother, the cook an. French man, and a sailor a beautiful young. Chinese boy. The sailor had broken his leg jumping into the lifeboat. The. sailor dies and the cook butchers and eats him. Pi and his mother. The cook kills Pis mother and. Pis direction. Soon after, Pi fights the cook. He eats his heart and liver and pieces of his flesh. Then, as Pi says to Okamoto and Chiba, Solitude began. I turned. to God. I survived. Okamoto and Chiba are appalled but notice all the parallels between. They ask more technical questions, but Pi can tell them nothing. Tsimtsums sinking. Pi asks them which story they preferred the one with animals or. Both Chiba and Okamoto agree that the one with. In his report, which years later. Martel, Okamoto writes that Pis story of survival at. Bengal tiger is astonishing and unique. Analysis. In the course of thirty pages, the sad tale we have been. Pi reveals another version, one in which the animals are replaced. Once we learn this, we immediately assume that Pi has. The beautiful, noble zebra represents the exotic Chinese. The gutless, violent, ugly hyena embodies all the revolting. The maternal orangutan. Pis own. mother. And the tiger is Pi himself, alternately vicious, passive. Both versions. of the storywith and without animalsare viable, and Pi never tells. Still, Pi seems to confess in. Only storytelling has.