Hiromitsu Takakura

Hemodynamic evaluation of 19-mm Carpentier-Edwards pericardial bioprosthesis in aortic position

BACKGROUND The aortic Carpentier-Edwards pericardial bioprosthesis offers good long-term clinical outcomes with a low rate of structural deterioration. However, little in vivo hemodynamic data is available for this bioprosthesis. METHODS To determine the hemodynamic performance of the 19-mm Carpentier-Edwards pericardial valve, both cardiac catheterization and dobutamine stress echocardiography were electively performed in 10 patients. The mean age at the study was 71.6 +/- 4.4 years and the mean body surface area was 1.39 +/- 0.11 m2. The peak-to-peak gradient, instantaneous peak gradient, mean gradient, and valve orifice area were measured by standard cardiac catheterization. The Doppler-derived gradients and valve orifice area were also measured both at rest and during dobutamine infusion. RESULTS The average peak-to-peak gradient, instantaneous peak gradient, mean gradient, and valve orifice area measured by catheterization were 13.0 +/- 5.4 mmHg, 28.5 +/- 7.7 mmHg, 12.0 +/- 4.9 mmHg, and 1.55 +/- 0.45 cm2, respectively. The peak and mean Doppler gradients, and valve orifice area by resting echocardiography were 27.7 +/- 9.5 mmHg, 12.3 +/- 4.8 mmHg, and 1.39 +/- 0.26 cm2, respectively. At a dosage of 10 microg/kg/min of dobutamine, the mean Doppler gradient rose mildly to 22.2 +/- 4.8 mmHg, while the cardiac output increased from 4.49 +/- 0.44 to 6.64 +/- 0.87 L/min. The valve orifice area during the 10 microg/kg/min dobutamine infusion (1.55 +/- 0.25 cm2) was significantly larger than its value at rest (p < 0.05). CONCLUSIONS With acceptable hemodynamic performance, use of the aortic 19-mm Carpentier-Edwards pericardial valve is a reliable option for elderly patients with a small annulus.

Right atrial myxoma complicated with pulmonary embolism

A 25-year-old woman was admitted to our hospital with chest pain and dyspnea, and was diagnosed as having a right atrial myxoma complicated with pulmonary embolism. An emergency operation was performed with cardiopulmonary bypass. A papillary pedunculated tumor was found having a narrow-based attachment to the free atrial wall. After the tumor was carefully removed together with the atrial wall around the attachment, pulmonary embolectomy was performed. Several fragments of the tumor were removed, and sufficient back-flow from the pulmonary artery was established. The postoperative course was uneventful. However, a non-perfused area was observed in the left lower lung on pulmonary hemodynamic scintigraphy at 3 months after the operation. Long-term observation is required due to the high risk for metastasis and recurrence, and further surgical treatment remains the most appropriate treatment option. A second operation may be needed to prevent progression in complications.

Congenital mitral regurgitation from absence of the anterolateral papillary muscle

A 21-year-old woman had congenital mitral regurgitation. Echocardiography showed absence of the anterolateral papillary muscle and corresponding marginal chordae. This rare abnormality was corrected by anterolateral commissural annuloplasty and insertion of artificial chordae to prevent prolapse of the anterior leaflet. Postoperatively, there was no regurgitation, and an appropriate mitral valve area was achieved.

Patient-prosthesis mismatch may be irrelevant after aortic valve replacement with the 19-mm Perimount pericardial bioprosthesis in patients aged 65 years or older.

The prevalence of patient–prosthesis mismatch (PPM) and its influence on clinical midterm results were examined in elderly patients whose activity was supposed to be less than that of younger patients. We evaluated valve function and the effects of PPM on the midterm results of the 19-mm Carpentier–Edwards Perimount (CEP) pericardial aortic valve in patients aged 65 years or older. Between August 1996 and May 2005, 51 patients underwent aortic valve replacement with the 19-mm CEP valve. The mean follow-up was 2.4 ± 1.8 years, involving a total of 134.4 patient-years. The mean age and body surface area at operation were 74.0 ± 5.0 years and 1.41 ± 0.14 m2. There were two (3.9%) operative deaths. Three patients (5.9%) underwent enlargement of their small aortic annuli. The actuarial survival rate at 8 years, including operative mortality, averaged 90.2% ± 4.7%. The freedom from thromboembolism, reoperation, and valve-related mortality averaged 75.0% ± 21.7%, 97.8% ± 2.2%, and 95.3% ± 3.2%, respectively, at 8 years. High preoperative peak and mean transvalvular pressure gradients were significantly improved after the operation (peak, 93 ± 35 versus 28 ± 12 mmHg; mean, 58 ± 19 versus 17 ± 7 mmHg, respectively; P < 0.01). The mean left ventricular mass index was reduced from 192 ± 44 to 142 ± 46 g/m2 at late follow-up (P < 0.01). The prevalence of PPM was low (17.6%) when an indexed effective orifice area of less than 0.85 cm2/m2 was taken as the definition of PPM. The clinical results, postoperative pressure gradients, and reduction in left ventricular mass index were not different between the PPM and no-PPM groups. The 19-mm CEP valve produced satisfactory midterm clinical outcomes in patients aged 65 years or older whose activity was supposed to be less than that of younger patients, regardless of the presence or absence of PPM. Moderate PPM was rare and it did not adversely impact on the midterm results. The application of annulus enlargement could be limited to the small number of patients for whom the 19-mm CEP valves are not able to be inserted.

Chronic dissecting aneurysm of the thoracic aorta following minor blunt trauma.

A 64-year-old man admitted for treatment of a thoracic aneurysm had experienced severe back pain 10 years earlier after falling heavily on his forearms. From the night following the fall, hoarseness and pleuritic chest wall pain continued for about 3 months. Preoperative imaging showed a chronic dissecting aneurysm near the aortic isthmus. The patients history suggested that the fall 10 years before surgery was the most likely cause.

Aortic valve repair with autologous pericardium for traumatic aortic valve regurgitation

We present a case of successful aortic valve repair for traumatic aortic valve regurgitation. A 26-year-old male who had a history of motor-cycle accident months prior to admission, was referred to our hospital for surgical treatment of severe aortic valve regurgitation. Intraoperative inspection revealed a tear in noncoronary cusp, with otherwise preserved valvular anatomy. Aortic valvuloplasty was successfully performed with closure using an autologous pericardium patch. Intraoperative transesophageal echocardiogram confirmed absence of residual regurgitation.

Jaundice After Surgery for an Aortic Arch Aneurysm

A 57-year-old patient who developed hyperbilirubinemia after surgery for an aortic arch aneurysm subsequently suffered pseudomonas sepsis. Low-volume biliary drainage from the common bile duct was colorless. A disturbance in the livers excretory system caused jaundice. Sepsis and jaundice were resolved when hepatic excretory function recovered.

A 22-year course of the Kay-Shiley disc valve with muscle guard at the mitral position.

Almost 33 years have elapsed since the introduction of the Kay-Shiley disc valve in Japan. Following the development of pyrolite carbon, the Kay-Shiley valve is no longer in clinical use. We report the case of a female patient who had had an isolated mitral valve replacement with the Kay-Shiley disc valve with single muscle guard 22 years previously. After numerous thromboembolic episodes with the Kay-Shiley disc valve, a successful reoperation was done with the CarboMedics valve. The explanted valve revealed that the grooved occluder disc had a loosely adherent clot. The thromboembolism is a notorious complication associated with this valve. We recommend re-replacement of the Kay-Shiley valve whenever possible.

Emergency Double Valve Replacement for Acute Mitral Regurgitation due to Ruptured Chordae Tendineae Associated with Congenital Bicuspid Aortic Valve Insufficiency.

僧帽弁逸脱症は腱索断裂を比較的高頻度に合併するが,感染性心内膜炎やMarfan症候群の合併なく急激に僧帽弁閉鎖不全を発症し,急性左心不全さらに,心停止にいたることは希である.今回,突然の急性左心不全にて発症し,救急外来受診直後心停止をきたした僧帽弁腱索断裂を伴う急性僧帽弁閉鎖不全症の43歳男性に対し,緊急手術を施行し良好な結果を得た.本症例では術中に先天性大動脈二尖弁による高度の閉鎖不全症の合併が判明し,これによる慢性左室容量負荷増大に加え,急性の腱索断裂が心停止をきたすほどの急性左心不全を招来した一因と考えられた.

Improved hemostasis with the combination of a heparin-coated circuit and aprotinin prime during open-heart surgery: potentiating effect on platelet preservation

Aprotinin administration with or without a heparin-coated circuit is expected to modulate subclinical plasma coagulation and fibrinolysis and platelet function during cardiopulmonary bypass. We studied the effect of the application of both, either one, or neither of an aprotinin prime (100 million KIU) and heparin-coated circuit in 32 consecutive patients undergoing coronary artery bypass surgery randomly divided into four groups of 8 patients each. Aprotinin was not used with the non-heparin-coated circuit in the control group. Levels of fibrinopeptide A were significantly lower in the heparin-coated circuit groups (P<0.05–0.01), irrespective of an aprotinin prime. D-dimer levels in the control group were significantly higher than in the other groups (P<0.05–0.01). The preservation rates of platelet count and function (acceleration of coagulation by platelet activating factor) in the control group were significantly lower than in the other three groups (P<0.05–0.01). Platelet preservation in the aprotinin plus heparin-coated group was significantly better than in the aprotinin only and the heparin-coated only groups (P<0.05). The amount of mediastinal drainage and the units of blood transfusion were significantly reduced in the two aprotinin groups, irrespective of heparin-coated use (P<0.01). The values in the aprotinin plus heparin-coated group were significantly less than the values in the heparin-coated only group (P<0.05). The heparin-coated circuit was beneficial for suppressing subclinical plasma coagulation and fibrinolysis and for preserving platelets. Addition of the minimal-dose aprotinin prime further preserved about a further reduction in postoperative blood loss and blood requirements.